Filter system using a filter bag assembly including a filter bag with a radial seal gasket - Patents.com

Abstract

Described herein is a filter system using a filter bag assembly including a filter bag with a gasket configured to form a radial seal, and corresponding methods of assembly and use thereof. The filter system, filter bag assembly, and filter bag with the gasket can be used in a filter system that removes particulate matter from air or other gases. Methods of use of the filter system and assembly of the filter bag to a filter service cage in the filter bag assembly are also described.

Description

Related Applications

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 292,221, filed December 21, 2021, entitled "FILTER SYSTEMS WITH FILTER BAG ASSEMBLIES INCLUDING FILTER BAGS WITH POCKET GASKETS," which is incorporated by reference in its entirety. [Technical field]

[0002] Described herein are filter systems that use filter bag assemblies that include filter bags with gaskets configured to form a radial seal, and corresponding methods of assembly and use thereof. [Background technology]

[0003] Many industries are faced with the problem of airborne particulate matter. In some industries, this particulate matter is a valuable product (e.g., starch) and it would be beneficial to be able to collect the airborne particulate matter and reintroduce it into the process. In other industries (e.g., metal or wood processing), it may be desirable to remove the particulate matter from the air to provide a cleaner working environment.

[0004] Some systems for purifying an air or other gas stream containing particulate matter include filter bags (sometimes called socks) disposed within a housing, typically constructed of a filter media such as woven fabric, pleated paper, etc. Typically, a gas stream contaminated with particulate matter passes through the housing such that the particulate matter is captured and retained by one or more filter bags.

[0005] An air filter system typically includes a clean air chamber and a dirty air chamber. The two chambers are separated by a structure commonly referred to as a tube sheet. The tube sheet has a number of openings that allow air to pass between the clean air chamber and the dirty air chamber. A filter bag is placed over the openings so that any particulate-laden air (dirty air) introduced into the dirty air chamber must pass through the filter bag to travel to the clean air chamber. Particulate matter in the dirty air is collected in the filter bag as the air travels through the filter bag.

[0006] From the clean air chamber, the clean air is exhausted to the environment or recirculated for other uses (see, e.g., Duyckinck, U.S. Pat. No. 6,299,433; Frey, U.S. Pat. No. 6,343,636; Robinson, U.S. Pat. No. 6,441,363; Robinson, U.S. Pat. No. 6,513,133; Ulvestad, U.S. Pat. No. 6,513,366; Robinson, U.S. Pat. No. 6,513,133; Howeth, U.S. Pat. No. 6,513,671; Tronto et al., U.S. Pat. No. 6,513,492; Muller et al., U.S. Pat. No. 6,513,821; Forsgren, U.S. Pat. No. 6,513,911; Kottet et al., U.S. Pat. No. 6,513,366; Clements, U.S. Pat. No. 6,513,492; Johnson et al., U.S. Pat. No. 6,513,671; Green et al., U.S. Pat. No. 6,513,821; and Kosmider et al., U.S. Pat. No. 6,513,821).

[0007] As the filter bags trap particulate matter, flow through the system is impeded and periodic cleaning of the filter bags can be performed to increase airflow through the system. Cleaning can be accomplished by periodically applying short pulses of pressurized air to the interior of the filter bag to reverse the airflow through the filter bag and force the collected particulate matter out of the filter bag, as described, for example, in U.S. Patent Nos. 5,393, 6,433, 6,513, 6,671, 6,711, 6,721, and 6,375. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Pat. No. 3,942,962 [Patent Document 2] U.S. Pat. No. 4,218,227 [Patent Document 3] U.S. Pat. No. 4,424,070 [Patent Document 4] U.S. Pat. No. 4,436,536 [Patent Document 5] U.S. Pat. No. 4,443,237 [Patent Document 6] U.S. Pat. No. 4,445,915 [Patent Document 7] U.S. Pat. No. 4,661,131 [Patent Document 8] U.S. Pat. No. 5,207,812 [Patent Document 9] U.S. Pat. No. 4,954,255 [Patent Document 10] U.S. Pat. No. 5,222,488 [Patent Document 11] U.S. Pat. No. 5,211,846 [Patent Document 12] U.S. Pat. No. 5,730,766 [Patent Document 13] U.S. Patent No. 6,090,173 [Patent Document 14] U.S. Patent No. 6,902,592 [Patent Document 15] U.S. Pat. No. 7,641,708 [Patent Document 16] U.S. Pat. No. 4,395,269 [Patent Document 17] US Patent Application Publication No. 2006 / 0112667 Summary of the Invention [Problem to be solved by the invention]

[0009] Described herein is a filter system using a filter bag assembly including a filter bag with a gasket configured to form a radial seal, and corresponding methods of assembly and use. The filter system, filter bag assembly, and filter bag can be used in a filter system to remove particulate matter from air or other gases. Methods of using the filter system and methods of assembling the filter bag in a filter service cage with the filter bag assembly are also described. [Means for solving the problem]

[0010] The filter bag assembly includes a service frame having a support ring that supports a gasket of a filter bag mounted to the service frame. The service frame includes an extension strut that supports a distal end strut disposed distally from the support ring. The support ring holds the bag opening of the filter bag open during placement of the filter bag assembly and removal of the filter bag assembly from the contaminated air chamber of the filter system. As a result, placement and removal of the filter bag in the same filter system is simplified.

[0011] In one or more embodiments, the gasket of the filter bag assembly forms a radial seal with a receiver surrounding an opening in the tube sheet that separates the housing of the air filter system into a clean air chamber and a dirty air chamber. The gasket on the filter bag engages the receiver to form a radial seal between a sealing surface on the receiver and the gasket such that air passing through the opening in the tube sheet must pass through the filter bag on its way through the opening to or from the dirty air chamber.

[0012] In one or more of the embodiments described herein, the support ring assists in forming a radial seal between the gasket and the receiver by compressing the gasket between the support ring and the receiver.

[0013] In one or more embodiments, the gasket is inserted into a receiver configured to receive the gasket to form the radial seal of some of the embodiments described herein.

[0014] In one or more embodiments described herein, the support ring assists in the formation of a radial seal between the gasket and the receiver by resisting expansion of the gasket by the receiver when the gasket is inserted over a receiver configured to receive the gasket to form some embodiments of the radial seal described herein. In embodiments where the radial seal is formed by inserting the gasket into the receiver, the support ring resists compression of the gasket to form some embodiments of the radial seal described herein.

[0015] In one or more embodiments of the air filter system described herein, the housing includes an access panel across the dirty air chamber from the tube sheet, and the filter bag assembly is sized to prevent disengagement of the gasket from the sealing surface of the receiver by closure of an access port in the access panel through which the filter bag assembly passes to place and remove it from the dirty air chamber. In one or more embodiments, the access cover used to close the access port acts on a distal end strut of the service cage of the filter bag assembly to prevent disengagement of the gasket from the sealing surface of the receiver, for example during pulse cleaning, where high pressure air / gas is directed through an opening in the tube sheet into the interior volume of the filter bag. Although undesired disengagement (e.g., during pulse cleaning) is prevented, the filter bag assembly still allows the gasket on the filter bag to be easily removed from the receiver during replacement of the filter bag assembly.

[0016] In one or more embodiments, placing an access cover on the access panel to close the access port may advance the gasket toward the tubesheet to assist in forming a radial seal between the sealing surface and the gasket at the receiver.

[0017] In one or more embodiments of the air filter systems described herein, a yoke is attached to the tube sheet near the opening, the yoke extending into the dirty air chamber. In one or more embodiments, the yoke can aid in placement of a gasket on or within the receptacle surface. In one or more embodiments, the yoke can help support the filter bag assembly during removal of the filter bag assembly from the dirty air chamber.

[0018] In one or more embodiments, the yoke may include an intermediate support structure configured to prevent undesired collapse of the filter bag during filtering of particulate matter from the polluted air being channeled into the polluted air chamber, and because the intermediate support structure is stationary and fixed within the dirty air chamber, the filter bag assembly has a reduced weight compared to air filter systems in which the intermediate support structure must be removed from the dirty air chamber along with the filter bag when the filter bag is replaced.

[0019] The filter bag assemblies and filter bags described herein may be particularly useful in filter systems designed for use in industrial air filtration applications where particulate matter must be removed from relatively large volumes of contaminated air. The filter bags and filter bag assemblies must therefore be sized to handle such volumes of air and the particulate matter associated with those volumes. In general, the bag length measured from the bag opening to the closed end of the bag in the filter bags described herein can be 0.3 meters or more, 0.5 meters or more, 1 meter or more, 1.5 meters or more, or 2 meters or more. The associated bag height (measured transversely to the bag length) can be 0.2 meters or more, 0.3 meters or more, 0.4 meters or more, or 0.5 meters or more.

[0020] A filter system including one or more of the various features and components described herein, in one or more embodiments, can provide one or more advantages, such as improved energy efficiency, reduced noise, etc., by reducing the pressure drop within the filter system during both primary flow operation and pulse cleaning of the filter elements (primary flow operation occurs when the filter system is removing particulate matter from the contaminated air stream), reducing friction losses in the filter system (both during primary flow operation and pulse cleaning of the filter bags), improved particle loading characteristics (thus potentially requiring fewer cleaning pulses), etc.

[0021] These benefits may be synergistic in one or more embodiments, i.e., energy efficiency, noise reduction, etc. may be improved by using two or more features and / or components together in the same filter system.

[0022] In a first aspect, one or more embodiments of the air filter system described herein include a tube sheet separating a housing into a dirty air chamber and a clean air chamber, where the tube sheet includes an opening that fluidly connects the dirty air chamber with the clean air chamber, the housing including an access panel directly across the dirty air chamber from the tube sheet; and a filter bag assembly configured to be installed in and removed from the dirty air chamber through an access port in the access panel. In one or more embodiments, the filter bag assembly includes a service frame including a support ring and a distal strut, the distal strut being attached to the support ring by an extension strut extending between the distal strut and the support ring, the support ring having a front edge facing away from the distal strut; a filter bag, the filter bag including a flexible filter sheet material and having a bag opening and a closed end such that an interior volume of the filter bag is defined; and a pocket gasket extending around the bag opening, the pocket gasket including a pocket, the front edge of the support ring being disposed within the pocket and adjacent the tube sheet when the filter bag assembly is installed in the dirty air chamber, and the extension strut extends away from the tube sheet toward the access panel. In one or more embodiments, the air filter system further includes a receiver surrounding the opening, the pocket gasket of the filter bag assembly engaging the receiver to form a radial seal between a sealing surface at the receiver and the pocket gasket such that air passing through the opening in the tube sheet must pass through the filter bag as it enters or leaves the dirty air chamber through the opening.

[0023] In one or more embodiments of the air filter systems described herein, the pocket gasket is compressed between the support ring and the sealing surface of the receiver.

[0024] In one or more embodiments of the air filter systems described herein, the leading edge of the support ring and the pocket of the pocket gasket are disposed within the receiver such that a radial seal is formed with the receiver and an outer surface of the support ring. In one or more embodiments, the pocket gasket comprises a seal member that is deformed by the receiver when the leading edge of the support ring and the pocket of the pocket gasket are disposed within the receiver.

[0025] In one or more embodiments of the air filter system described herein, the pocket gasket includes a forward edge distal from the closed end of the filter bag along the filter bag axis, and the receiver is disposed within the pocket gasket such that a radial seal is formed within the pocket gasket and outside the receiver at a location between the forward edge of the pocket gasket and the closed end of the filter bag. In one or more embodiments, the receiver is disposed within the pocket gasket such that a radial seal is formed within the pocket gasket on an outer surface of the receiver that faces the pocket gasket. In one or more embodiments, the pocket gasket includes a seal member that is deformed by the receiver when the receiver is positioned within the pocket gasket, and a radial seal is formed within the pocket gasket on an outer surface of the receiver that faces the pocket gasket.

[0026] In one or more embodiments of the air filter systems described herein, the service frame comprises a filter bag assembly length, measured along the filter bag axis between the forward edge of the support ring and the distal end post, that is large enough to prevent disengagement of the pocket gasket from the sealing surface of the receiver when the access port is closed.

[0027] In one or more embodiments of the air filter systems described herein, the radial seal formed between the sealing surface of the receiver and the support ring is located between a leading edge of the support ring and a trailing edge of the support ring, which is located between the leading edge of the support ring and the distal end post.

[0028] In one or more embodiments of the air filter system described herein, the support ring, the distal end strut, and the extension strut of the service frame are disposed within the interior volume of the filter bag. In one or more embodiments, the extension strut comprises a first extension strut and the service frame comprises a second extension strut extending between the distal end strut and the support ring, and the support ring, the first extension strut, the second extension strut, and the distal end strut define a generally rectangular shape of the service frame.

[0029] In one or more embodiments of the air filter system described herein, the support ring, the distal end struts, and the extension struts of the service frame are disposed outside the interior volume of the filter bag. In one or more embodiments, the extension struts include first extension struts and the service frame includes second extension struts extending between the distal end struts and the support ring, and the support ring, the first extension struts, the second extension struts, and the distal end struts define a generally rectangular shape of the service frame.

[0030] In one or more embodiments of the air filter systems described herein, the system includes a yoke attached to the tube sheet, the yoke extending from the dirty air chamber side of the tube sheet into the dirty air chamber, a joint between the yoke and the tube sheet located between the opening and the sealing surface of the receiver, and when the filter bag assembly is installed in the dirty air chamber, the yoke is disposed within the interior volume of the filter bag.

[0031] In one or more embodiments of the air filter systems described herein, the system includes a yoke attached to the tube sheet, the yoke extending from the dirty air chamber side of the tube sheet into the dirty air chamber, a joint between the yoke and the tube sheet being located between the opening and the sealing surface of the receiver, the yoke being located within the interior volume of the filter bag when the filter bag assembly is installed in the dirty air chamber, the yoke including a strut channel extending away from the tube sheet along an edge of the yoke, and the extension strut of the service frame being at least partially received within the strut channel. In one or more embodiments, the extension strut of the service frame is disposed within the interior volume of the filter bag.

[0032] In one or more embodiments of the air filter systems described herein, the service frame and yoke define a handle gap between the service frame and yoke near the closed end of the tubular body, the handle gap being located between the closed end of the tubular body and the yoke, and the handle gap being configured to facilitate manual gripping of the service frame and filter bag to remove the filter bag assembly from the contaminated air chamber.

[0033] In one or more embodiments of the air filtration systems described herein, the leading edge of the support ring is configured such that the distance between the leading edge of the support ring and the tubesheet varies around the circumference of the support ring.

[0034] In one or more embodiments of the air filter systems described herein, the pocket gasket is constructed from a resilient elastomeric material.

[0035] In one or more embodiments of the air filter systems described herein, the pocket gasket comprises a forward edge located distally from the closed end of the filter bag along the filter bag axis and a rearward edge located between the forward edge and the closed end of the filter bag, and the pocket gasket is attached to the flexible filter sheet material of the filter bag at a seam located between the pocket and the rearward edge of the pocket gasket.

[0036] In one or more embodiments of the air filter systems described herein, the pocket gasket includes a forward edge located distally from the closed end of the filter bag along the filter bag axis, and the pocket gasket is attached to the flexible filter sheet material of the filter bag at a seam located between the pocket and the forward edge of the pocket gasket.

[0037] In one or more embodiments of the air filter systems described herein, the system includes an access port cover configured to close the access port when the filter bag assembly is installed in the dirty air chamber and a pocket gasket of the filter bag engages the receiver to form a radial seal between the sealing surface of the receiver and the pocket gasket, and a chamber crossing distance across the dirty air chamber from the access port cover to the receiver is configured to prevent disengagement of the pocket gasket from the sealing surface of the receiver when the access port is closed by the access port cover. In one or more embodiments, the access port cover is configured to limit movement of the distal end post in a direction transverse to the filter bag axis when the access port is closed by the access port cover.

[0038] In one or more embodiments of the air filter system described herein, the opening in the tube sheet includes a first opening of a plurality of openings, each opening of the plurality of openings fluidly connects the dirty air chamber to the clean air chamber, the filter bag assembly includes a first filter bag assembly of the plurality of filter bag assemblies, each filter bag assembly of the plurality of filter bag assemblies configured to be installed in and removed from the dirty air chamber through an access port in the access panel, the receiver includes a first receiver of the plurality of receivers, each receiver extends into the dirty air chamber around one of the plurality of openings, a pocket gasket of the first filter bag assembly engages the first receiver to form a radial seal between a sealing surface at the first receiver and the pocket gasket such that air passing through the first opening must pass through a filter bag of the first filter bag assembly as it passes through the first opening to or from the dirty air chamber, and a second opening of the plurality of openings includes a second receiver of the plurality of openings. a pocket gasket of a second filter bag assembly of the plurality of filter bag assemblies is disposed within a second one of the receivers and engages the second receiver, a filter bag axis extending through the bag opening and the closed end of the filter bag of the first filter bag assembly is a first filter bag axis extending through a center of the bag opening and a center of the closed end of the filter bag of the first filter bag assembly, the filter bag of the second filter bag assembly defines a second filter bag axis extending through a center of the bag opening and a center of the closed end of the filter bag of the second filter bag assembly, the filter bag of the first filter bag assembly has a width measured in a width direction that is transverse to both the first filter bag axis and the second filter bag axis, the first filter bag assembly and the second filter bag assembly are adjacent to one another in the width direction, and a distance along the width direction between the first filter bag axis and the second filter bag axis is greater than or equal to three times the width of the first filter bag.

[0039] In one or more embodiments of the air filter system described herein, in which the distance along the width between the first filter bag axis and the second filter bag axis is greater than or equal to three times the width of the first filter bag, each filter bag assembly of the plurality of filter bag assemblies extends across the contaminated air chamber from the receiver to the access panel.

[0040] In one or more embodiments of the air filter system described herein, where the distance along the width between the first filter bag axis and the second filter bag axis is three or more times the width of the first filter bag, the plurality of filter bag assemblies includes three or more filter bag assemblies, and the inter-assembly distance between each pair of adjacent filter bag assemblies of the plurality of filter bag assemblies is the same as or greater than the distance between the first filter bag axis and the second filter bag axis.

[0041] In one or more embodiments of the air filter system described herein, where the distance along the width between the first filter bag axis and the second filter bag axis is greater than or equal to three times the width of the first filter bag, the filter bag of each filter bag assembly of the plurality of filter bag assemblies comprises an envelope-type filter bag.

[0042] In one or more embodiments of the air filter systems described herein, the front edge of the support ring includes a plurality of retention tabs extending away from the closed end of the filter bag, and the pocket gasket includes a plurality of tab openings configured to receive the retention tabs, optionally extending from the pocket through a front edge of the pocket gasket and through the pocket gasket such that the plurality of retention tabs are exposed at the front edge of the pocket gasket.

[0043] In one or more embodiments of the air filter systems described herein, the filter bag comprises an envelope-type filter bag.

[0044] In one or more embodiments of the air filter systems described herein, the filter bag includes a handle attached to a closed end of the tubular body, the closed end being located axially between the bag opening and the handle.

[0045] In a second aspect, one or more embodiments of the filter bag described herein include a tubular body extending from a bag opening to a closed end, the tubular body defined by a flexible filter sheet material that defines an interior volume of the filter bag between the bag opening and the closed end, the tubular body defining a filter bag axis extending through the bag opening and the closed end; a gasket attached to the tubular body, the gasket extending around the bag opening and attached around the bag opening, the gasket comprising: an outer surface extending around an outer periphery of the gasket facing away from the filter bag axis; an inner surface extending around an outer periphery of the gasket facing the filter bag axis; a forward edge located distally from the closed end of the tubular body; a rear edge located between the forward edge and the closed end of the tubular body; and a pocket formed in the gasket between the outer surface and the inner surface, the pocket comprising a pocket opening and a forward end, the forward end being located between the pocket opening and the forward edge of the gasket, the pocket configured to receive a support ring extending around the bag opening.

[0046] In one or more embodiments of the filter bags described herein, the pocket opening opens into the interior volume of the filter bag.

[0047] In one or more embodiments of the filter bags described herein, the pocket opening faces the closed end of the tubular body.

[0048] In one or more embodiments of the filter bags described herein, the pocket opening is located closer to the forward edge of the gasket than to the trailing edge of the gasket.

[0049] In one or more embodiments of the filter bags described herein, the pocket comprises a pocket depth measured along the bag axis between a forward end of the pocket and a reference plane oriented transversely to the bag axis, where the pocket depth varies around the circumference of the gasket.

[0050] In one or more embodiments of the filter bags described herein, the gasket comprises a gasket depth measured along the bag axis between the forward edge and a reference plane oriented transversely to the bag axis, where the gasket depth varies around the circumference of the gasket.

[0051] In one or more embodiments of the filter bags described herein, the gasket comprises a gasket-pocket depth measured along the bag axis between a forward end of the pocket and a reference plane, where the gasket-pocket depth varies around the circumference of the gasket.

[0052] In one or more embodiments of the filter bags described herein, the gasket includes one or more sealing members protruding from the gasket, the one or more sealing members being disposed between a forward edge and a rear edge of the gasket.

[0053] In one or more embodiments of the filter bags described herein, one or more seal members are disposed between the pocket opening and the trailing edge of the gasket.

[0054] In one or more embodiments of the filter bags described herein, the one or more seal members are disposed between the pocket opening and the forward edge of the gasket. In one or more embodiments, the one or more seal members are disposed between the forward end of the pocket and the forward edge of the gasket.

[0055] In one or more embodiments of the filter bags described herein, the one or more sealing members protrude from an outer surface of the gasket.

[0056] In one or more embodiments of the filter bags described herein, the one or more sealing members protrude from the inner surface of the gasket.

[0057] In one or more embodiments of the filter bags described herein, the one or more sealing members comprise one or more materials selected from a foamed elastomer, a loose felt, a pile / fuzzy gasket material, and a solid elastomer.

[0058] In one or more embodiments of the filter bags described herein, each of the one or more sealing members extends continuously around the circumference of the gasket.

[0059] In one or more embodiments of the filter bag described herein, the filter bag comprises a handle attached to a closed end of the tubular body, the closed end being located in the filter bag axial direction between the bag opening and the handle, and optionally the closed end of the tubular body being defined by a seal formed between opposing layers of flexible filter sheet material, and optionally the seal comprising a stitch. In one or more embodiments, the handle comprises a handle opening formed in the flexible filter sheet material.

[0060] In one or more of the embodiments of the filter bags described herein, the gasket includes a plurality of tab openings that extend through the gasket from the forward end of the pocket through the forward edge of the gasket.

[0061] The use of any of the filter systems, filter bag assemblies, and filter bags with pocket gaskets described herein for removing particulate matter from contaminated air (or any other gas) is also described herein.

[0062] As used in this specification and the appended claims, the singular forms "a," "an," and "the" or "said" include plural referents unless the context clearly indicates otherwise. Thus, for example, reference to "a," "the," or "said" element can include one or more components and equivalents thereof known to those skilled in the art. Furthermore, the term "and / or" means one or all of the listed elements or a combination of any two or more of the listed elements.

[0063] It should be noted that the term "comprises" and variations thereof do not have a limiting meaning when these words appear in the description. Furthermore, "a," "an," "the," "at least one," and "one or more" are used interchangeably herein.

[0064] The above summary is not intended to describe each embodiment or every implementation of the air filter system, filter bag assembly, filter bag with pocket gasket, and method described herein, but rather the invention will become more apparent and more fully understood by considering the accompanying drawings and the following description of exemplary embodiments and the claims. [Brief description of the drawings]

[0065] [Figure 1] 1 is a perspective view of one exemplary embodiment of an air filter system described herein. [Figure 2A] 4 illustrates components of another exemplary embodiment of an air filter system described herein. [Figure 2B] 2B-2B of FIG. 2A shows the components of the air filter system of FIG. 2A taken along line 2B-2B of FIG. 2A. [Diagram 3] FIG. 2 is a perspective view of one example embodiment of a filter bag assembly engaged within a receiver in a tube sheet of one example embodiment of an air filter system described herein. [Figure 4]FIG. 1 is an exploded perspective view of one exemplary embodiment of a filter bag assembly described herein along with a yoke assembly that can be used with one or more embodiments of the filter bag assembly described herein. [Diagram 5] 5 is an enlarged cross-sectional view of the filter bag assembly, receptacle, and tube sheet of FIG. 3 taken along line 5-5 of FIG. 3. [Figure 6] 13 is an enlarged cross-sectional view of another example embodiment of a filter bag assembly engaged within a receiver in a tube sheet of another example embodiment of an air filter system described herein. [Figure 7] 7 is an enlarged cross-sectional view of the filter bag assembly, receptacle, and tube sheet shown in FIG. 6 taken along line 7-7 of FIG. 6. [Figure 8] 13 is an enlarged cross-sectional view of another example embodiment of a filter bag assembly engaged within a receiver in a tube sheet of another example embodiment of an air filter system described herein. [Figure 9] 9 is an enlarged cross-sectional view of the filter bag assembly, receiver, and tube sheet shown in FIG. 8 taken along line 9-9 of FIG. 8. [Figure 10] FIG. 13 is a perspective view of another exemplary embodiment of a filter bag assembly partially attached to a yoke assembly of another exemplary embodiment of an air filter system including a tube sheet and receiver as described herein. [Figure 11] 1 is a perspective view of one exemplary embodiment of a service frame that can be used in one or more embodiments of the air filtration system described herein. [Figure 12] 12 is a perspective view of one exemplary embodiment of a filter bag that can be attached to the service frame shown in FIG. 11. [Figure 13] FIG. 2 is an enlarged perspective view of a filter bag assembly partially attached to a yoke assembly of one exemplary embodiment of an air filter system including a tube sheet and receiver as described herein. [Figure 14]FIG. 14 is an enlarged perspective view of one exemplary embodiment of a service frame used in the exemplary embodiment of the filter bag assembly shown in FIG. 13 with the filter bag removed from the service frame and the service frame partially attached to the yoke assembly shown in FIG. [Figure 15] FIG. 14 is another perspective view of the filter bag assembly, yoke assembly, tube sheet, and receiver shown in FIG. 13. [Figure 16] FIG. 14 is a perspective cross-sectional view of the filter bag assembly, yoke assembly, tube sheet, and receiver shown in FIG. 13. [Figure 17] FIG. 17 is an enlarged view of the components shown in FIG. 16 after the pocket gasket of the filter bag has been engaged with the receiver in the tube sheet. [Figure 18] FIG. 1 is a perspective view of another exemplary embodiment of a filter bag assembly partially attached to a yoke assembly of another exemplary embodiment of an air filter system including a tube sheet and receiver as described herein (filter material of the filter bag has been removed to expose components disposed within the filter bag). [Figure 19] FIG. 19 is an enlarged view of the upper portion of the filter bag assembly shown in FIG. [Figure 20A] 20 is an enlarged cross-sectional view of the upper portion of the filter bag assembly shown in FIG. 18 taken along line 20-20 of FIG. 18. [Figure 20B] FIG. 20B is a close-up view of the joint between the pocket gasket and the receiver of the filter bag assembly of FIG. 20A. [Figure 21A] FIG. 13 is a perspective view of another exemplary embodiment of a service frame including a support ring as described herein, the support ring including a retention tab configured to retain a gasket on the service frame during installation. [Figure 21B] FIG. 21B is a perspective view of the service frame of FIG. 21A after the pocket gasket of the filter bag has been attached to the support ring. [Figure 21C]FIG. 21C is a perspective view of a pocket gasket and service frame installed in a receiver described herein, with FIG. 21C being a view from the tube sheet side of the receiver with the tube sheet removed to expose features in the receiver and filter bag assembly. [Figure 21D] FIG. 21D is a side view of one of the retention tabs on the support ring of FIGS. 21A-21C with the gasket shown in cross section. [Fig. 21E-21F] 13A-13C show two exemplary embodiments of alternative retention tabs on a support ring. [Figure 22] 13 is a plan view of a portion of another exemplary embodiment of a filter bag assembly attached to a yoke assembly of another exemplary embodiment of an air filter system including a tube sheet and receiver as described herein. FIG. [Figure 23] 23 is a cross-sectional view of the entire filter bag assembly of FIG. 22 taken along line 23-23 of FIG. 22. [Figure 24] 23. A cross-sectional view of the filter bag assembly shown in FIG. 22 taken at a position between the upper yoke member 872 and the intermediate yoke member 873 shown in FIG. [Diagram 25] 23 is an enlarged cross-sectional view of the components of the filter bag assembly of FIGS. 22-24, taken near tubesheet 820, along line 23-23 of FIG. 22. FIG. [Figure 26] FIG. 26 is an enlarged cross-sectional view of the arrangement of receiver 830 and pocket gasket 860 and related components of the filter bag assembly of FIGS. [Figure 27] FIG. 27 is an enlarged cross-sectional view of the pocket gasket 860 and filter bag 850 separated from the other components shown in FIG. [Figure 28] 13 is a plan view of a portion of another exemplary embodiment of a filter bag assembly attached to a yoke assembly of another exemplary embodiment of an air filter system including a tube sheet and receiver as described herein. FIG. [Figure 29] 29 is an enlarged cross-sectional view of the components of the filter bag assembly of FIG. 28 taken along line 29-29 of FIG. 28. [Diagram 30]29 is a cross-sectional view of the filter bag assembly shown in FIG. 28 taken at a position between the upper yoke member 972 and the intermediate yoke member 973 shown in FIG. [Diagram 31] FIG. 31 is an enlarged cross-sectional view of the arrangement of receiver 930 and pocket gasket 960 and related components of the filter bag assembly of FIGS. 28-30. [Figure 32-1] FIG. 1 is a perspective view of another exemplary embodiment of a service frame for a gasket assembly and filter bag assembly, with the filter bag shown in dashed lines to expose the service frame, and the gasket assembly shown in cross section along a plane defined by the service frame. [Figure 32-2] FIG. 32-2 is an enlarged view of the gasket assembly of FIG. 32-1. [Figure 32-3] FIG. 32-1 is an enlarged view of the joint between one extension strut and a gasket assembly of the service frame of FIGS. 32-1 and 32-2. [Figure 32-4] FIG. 32-2 is an enlarged view of the upper end of the gasket assembly of FIG. 32-1. [Figure 32-5] 11 is a cross-sectional view of another exemplary embodiment of a gasket assembly of a filter bag disposed within a receiver as described herein. [Figure 32-6] 11 is a cross-sectional view of another exemplary embodiment of a gasket assembly of a filter bag disposed on a receiver surface as described herein. [Diagram 33] 13 is a diagram of another embodiment of a filter system including a receiver as described herein and a filter bag with a gasket. [Diagram 34] FIG. 13 is another embodiment of a filter bag with a gasket and service frame as described herein. [Diagram 35] 35 is a cross-sectional view of the filter bag and gasket of FIG. 34 taken along line 35-35 of FIG. 34. [Diagram 36] 1 is a perspective view of one example embodiment of an access port and access port cover that can be used in one or more embodiments of the air filter system described herein. [Figure 37]FIG. 13 is a perspective view of an alternative access port cover that may be used in one or more embodiments of the air filter systems described herein. [Fig. 38A-38B] 1 illustrates an alternative access port cover that may be used in one or more embodiments of the air filter systems described herein. [Figures 39A-39C] 1 illustrates an alternative access port cover that may be used in one or more embodiments of the air filter systems described herein. [Figures 40A-40C] 1 illustrates an alternative access port cover that may be used in one or more embodiments of the air filter systems described herein. [Diagram 41] 1 illustrates another embodiment of an access port cover that may be used in one or more embodiments of the air filtration systems described herein. [Diagram 42] 11 is a side view of another exemplary embodiment of a filter bag assembly including a service frame attached to a yoke such that a handle gap is provided between the service frame and the yoke; FIG. [Diagram 43] FIG. 43 is an enlarged view of the closed end of the filter bag of FIG. 42 and the distal end of the service frame and yoke. [Figure 44-45] 1 illustrates two alternative exemplary embodiments of a handle gap defined between a service frame and a yoke. [Figure 46-49] 1 illustrates an example embodiment of a handle provided at a closed end of one or more embodiments of a filter bag described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0066] In the following description of exemplary embodiments, reference is made to the accompanying drawings, which form a part hereof and which show, by way of illustration, specific embodiments, It is understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.

[0067] Figure 1 illustrates one exemplary embodiment of an air filter system 10. The air filter system 10 illustrated in Figure 1 is generally box-shaped and includes a pair of opposing side wall panels 12 (only one of which is shown in Figure 1), a top wall panel 13, and an access panel 14. Also shown in Figure 1 is the edge of a tube sheet 20, which divides the housing of the air filter system 10 into a dirty air chamber 22 and a clean air chamber 24.

[0068] The air filter system 10 also includes a dirty air inlet 16 for receiving dirty or contaminated air (i.e., air entrained with particulate matter) into the dirty air chamber 22. Although not shown, the air filter system 10 also includes a clean air outlet for removing clean or filtered air from the clean air chamber 24 of the air filter system 10. A hopper 15 is positioned below the dirty air chamber 22 for collecting particulate matter separated from the contaminated air stream as described herein. The hopper 15 may include a sloping wall to facilitate collection of the particulate matter, and in one or more embodiments may include a driven auger or other mechanism for removing the collected particulate matter.

[0069] The illustrated air filter system 10 also includes an access panel cover 17 having a handle 19. The access panel 14 has an opening through which a filter bag assembly as described herein can be removed from and / or placed into the contaminated air chamber 22 of the air filter system 10, and the access panel cover 17 closes the opening.

[0070] 2A illustrates components found in one or more embodiments of the air filter system described herein. Similar to the air filter system 10 shown in FIG. 1, the embodiment of the air filter system 110 illustrated here includes a top wall panel 113, an access panel 114, and a tube plate 120 that separates a dirty air chamber 122 from a clean air chamber within the air filter system 110. Also included is a hopper 115 located below the dirty air chamber 122, and an access panel cover 117 having a handle 119 that closes an opening in the access panel 114 through which the filter bag assembly 140 / 150 can be removed from and / or placed into the dirty air chamber 122.

[0071] 2A also shows the receiver 130 and pocket gasket 160 on the filter bag 150 of the filter bag assembly 140 / 150. As described herein, the pocket gasket 160 forms a seal with the receiver 130 such that air passing through the opening in the tube sheet 120 must pass through the filter bag 150 of the filter bag assembly 140 / 150 as it passes through the opening in the tube sheet 120 and into or out of the dirty air chamber 122.

[0072] Other features shown in FIG. 2A include the components of a pulse cleaning device, which includes a manifold 125 and a nozzle 126 configured to direct a pulse of air or another pressurized gas through a receiver and into the interior volume of the filter bag 150 of the filter bag assembly 140 / 150. The details of such pulse cleaning devices and their operation are known and will not be described further herein. The components of the pulse cleaning device are disposed within the clean air chamber. Another feature shown in FIG. 2 related to the air filter system 110 is the dirty air inlet 116 configured to receive dirty or contaminated air into the dirty air chamber 122, and the clean air outlet 128 configured to remove clean or filtered air from the clean air chamber 124.

[0073] 2A , the filter bag 150 of the filter bag assembly 140 / 150 includes a bag opening adjacent the pocket gasket 160 and a closed end adjacent the access panel 114. The filter bag 150 is typically manufactured from a flexible filter sheet material that defines an interior volume of the filter bag 150. The filter bag 150 further defines a filter bag axis 111 that extends through the bag opening (located adjacent the pocket gasket 160) and the closed end (located adjacent the access panel 114) of the filter bag 150.

[0074] FIG. 2B is a view of the air filter system 110 of FIG. 2A with the top panel 113 removed to expose the components inside the housing. The components shown include a receiver 130 and a pocket gasket 160 of the filter bag 150 of the filter bag assembly 140 / 150. As described herein, the pocket gasket 160 forms a seal with the receiver 130 such that air passing through the opening in the tube sheet 120 must pass through the filter bag 150 of the filter bag assembly 140 / 150 as it passes through the opening in the tube sheet 120 and into the contaminated air chamber 122. Also shown in FIG. 2B are components of a pulse cleaning apparatus, including a manifold 125 and a nozzle 126 configured to direct pulses of air or another pressurized gas through the receiver 130 and into the interior volume of the filter bag 150 of the filter bag assembly 140 / 150.

[0075] As described and / or illustrated herein with respect to the filter bags used in one or more embodiments of the air filter systems described herein, the filter bag may be in the form of an envelope-type filter bag having connections on the two major sides along a pair of edges that extend from the bag opening to a closed end of the filter bag.

[0076] The distance between the two sides may also be relatively small compared to the height of the filter bag measured from edge to edge, and relatively small compared to the length of the filter bag measured from the bag opening to the closed end of the bag. In one or more embodiments, the height of the filter bag may be 10 times or more, 15 times or more, or 20 times or more the distance between the two major sides of the filter bag.

[0077] The distance between the two sides may also be relatively small compared to the length of the filter bag as measured from the bag opening to the closed end of the bag. In one or more embodiments, the length of the filter bag may be 20 times or more, 25 times or more, or 30 times or more the distance between the two major sides of the filter bag.

[0078] The diagram of the air filter system shown in Figure 2B illustrates the spacing of the filter bag assemblies 140 / 150 as they traverse the contaminated air chamber 122 in the X-axis direction of the Cartesian coordinate system shown in Figures 2A-2B (and also seen in Figure 1). Although the illustrated embodiment includes a set of five filter bag assemblies 140 / 150, one or more embodiments of the air filter system described herein may have as few as two, three, or four filter bag assemblies, or six or more filter bag assemblies.

[0079] Features illustrated for the top pair of filter bag assemblies include a filter bag axis 111 that extends through the center of an opening located in the receiver 130 in which the filter bag assembly 140 / 150 is mounted. The filter bag axis 111 extends through the filter bag 150 to the center of the closed end of the filter bag that is located in the access panel 114 / access panel cover 117.

[0080] The top filter bag 150 has a width W measured widthwise along the X-axis and transverse to both of the two filter bag axes 111 that extend through the pair of top filter bag assemblies 140 / 150. In many embodiments, the width W corresponds to the distance between the two major sides of an envelope-type filter bag.

[0081] The pair of top filter bag assemblies 140 / 150 can be described as adjacent to one another in the width direction. In one or more embodiments, the distance S between the filter bag axes 111 of adjacent filter bag assemblies 140 / 150, measured in the width direction (as defined herein), may be three times or more the width W of the first filter bag assembly 140 / 150. In one or more embodiments, the distance S may be four times or more, five times or more, or six times or more the width W of the first filter bag assembly 140 / 150.

[0082] In those embodiments including three or more filter bag assemblies 140 / 150, the spacing between adjacent filter bag assemblies in each pair of the plurality of filter bag assemblies is the same as or greater than the distance S between the topmost pair of filter bag assemblies 140 / 150.

[0083] Compared to known filter bag systems, the increased filter bag assembly spacing has been increased even though it may reduce the surface area of ​​the filter material making up the filter bag 150. To at least partially offset the reduced filter material surface area, the filter bag assemblies 140 / 150 extend across the contaminated air chamber from the receptacle 130 to the access panel 114 / access panel cover 117.

[0084] The increased spacing between adjacent pairs of filter bag assemblies provides numerous advantages over similar conventional air filter systems in which the filter bags are positioned closer together, including changes in flow characteristics such as reduced interstitial flow velocity between the filters and potentially creating a more uniform flow field across the entire cross-sectional area within the dirty air chamber, as well as changes in operational characteristics such as improved ability to allow debris with stringy characteristics to fall into the collection hopper without bridging or nesting between the filter bags, improved ability to allow debris with fluffy (e.g., low density) characteristics to fall into the collection hopper without remaining suspended in the dirty air chamber between adjacent filter bags, and improved ability to withstand wear that may be caused by high velocity areas between closer spaced filter bags.

[0085] One exemplary embodiment of a filter bag assembly 240 / 250 engaged with a receiver 230 in a tube sheet 220 of an air filter system is shown in the perspective view of Figure 3. Although only a portion of the filter bag assembly 240 / 250 is shown in Figure 3, the filter bag axis 211 defined by the filter bag 250 of the filter bag assembly 240 / 250 is also shown in Figure 3. A pair of extension posts 242, 244 of the service frame to which the filter bag 250 is attached are also shown in Figure 3.

[0086] 4 shows the filter bag assembly 240 / 250 in an exploded view with the yoke assembly 270 in which the filter bag assembly 240 / 250 is disposed when the filter bag assembly 240 / 250 is engaged with the receiver 230 as shown in FIG 3. The filter bag assembly 240 / 250 includes a service frame 240 and a filter bag 250. As described herein, the filter bag assembly 240 / 250 is configured to be installed in and removed from the dirty air chamber of an air filter system through an access port in an access panel of the air filter system.

[0087] The illustrated exemplary embodiment of filter bag 250 includes a bag opening 254 and a closed end 256, where filter bag 250 is constructed of a flexible filter sheet material with a body 252 that defines an interior volume of filter bag 250. As described herein, filter bag 250 extends along a filter bag axis 211 that extends through bag opening 254 and closed end 256 of filter bag 250.

[0088] The filter bag 250 also includes a pocket gasket 260 that extends around the bag opening 254. The pocket gasket 260 includes a pocket configured to receive the support ring 246 of the service frame 240 when the filter bag 250 is attached to the service frame 240 to form the filter bag assembly 240 / 250 as described herein. The pocket gasket 260 is preferably attached to the flexible filter sheet material of the body 252 in a manner that prevents air from entering or leaving the interior volume defined by the filter bag 250 through the joint between the pocket gasket 260 and the flexible filter sheet material of the body 252. Suitable attachment methods include one or more of, but are not limited to, sewing, adhesives, tape, heat welding, chemical welding, and the like.

[0089] The illustrated exemplary embodiment of the service frame 240 includes a support ring 246 and a distal end post 248 with a pair of extension posts 242, 244 extending from the support ring 246 to the distal end post 248. In the illustrated exemplary embodiment, the extension posts 242, 244 and the distal end post 248 define a generally rectangular service frame shape that corresponds to the shape of the filter bag 250. However, it is understood that the service frame used in one or more embodiments of the air filter systems described herein can take a variety of other shapes, although it may be preferred that the shape of the service frame corresponds to the shape of the filter bag used with the service frame.

[0090] The extension struts 242, 244 and the distal end struts 248 may be constructed of any suitable material having sufficient rigidity to maintain their shape when the filter bag 250 is attached. In one or more embodiments, the struts 242, 244, 248 may be constructed of solid or hollow metal rods / tubes, although any other suitable material and / or shape may be used in place of the metal rods / tubes.

[0091] The support ring 246 may also be constructed of any suitable material having sufficient rigidity to maintain its shape when the filter bag 250 is attached to the service frame 240. In one or more embodiments, the support ring 246 may be constructed of a metal sheet material that forms a ring shape capable of holding open the filter bag opening 254 and is shaped to be received on or within a receptacle surface of the air filter system described herein.

[0092] As described herein, the body 252 of the filter bag 250 is constructed of a filter sheet material that is configured to filter air or any other gas passing through the filter sheet material forming the body 252. Particulate matter entrained in the air or other gas becomes trapped within or on the filter sheet material forming the body 252. Typically, the filter sheet material is sufficiently flexible to allow the filter sheet material to flex during pulse cleaning as described herein, and the flexing or movement of the filter sheet material preferably results in the removal of at least a portion of the particulate matter trapped within or on the filter sheet material forming the filter body 252. The construction of such filter sheet materials is well known to those skilled in the art and may be, for example, woven materials, nonwoven materials, paper, etc., and may be selected taking into consideration the particulate matter to be collected, the airflow requirements, the strength requirements, etc. Suitable filter bags may be constructed of filter sheet materials such as one or more of polyester, polypropylene, aramid, polyester / polytetrafluoroethylene materials, in both woven and / or nonwoven constructions.

[0093] In one or more embodiments, the filter bags described herein can be distinguished from filter cartridges based on their response to a compressive force directed between the filter bag opening and the closed end of the filter bag, i.e., the end of the bag opposite the bag opening. In the absence of any external support (such as a service frame described herein as part of the filter bag assembly), the filter bags described herein, in one or more embodiments, deform with a compressive force of 5 Newtons (approximately 1.1 pounds-force) in the direction of a line extending through the bag opening to the closed end of the filter bag (e.g., along the bag axis 211 shown in FIG. 4). In addition to deformation, one or more embodiments of the filter bags used in the filter bag assemblies described herein transmit substantially no such compressive force. In contrast, the filter cartridges transmit most, if not all, of such compressive forces with little deformation. However, the flexibility of the filter sheet material that causes the filter bags used in the filter bag assemblies and filter systems described herein to be incapable of transmitting compressive forces is also the reason that the filter bags can rapidly accelerate outward (sometimes referred to as "snap") in response to a cleaning pulse to dislodge particulate matter collected by the filter sheet material.

[0094] 4 includes a lower yoke member 272, an upper yoke member 274, and a distal yoke member 278. The yoke assembly 270 also includes, in the illustrated example embodiment, a pulse collector 277 to which the lower yoke member 272 and the upper yoke member 274 are attached. The lower yoke member 272, the upper yoke member 274, the distal yoke member 278, and the pulse collector 277 generally define a generally rectangular shape.

[0095] The yoke assembly 270 also includes an intermediate support structure 275 that extends between the lower yoke member 272 and the upper yoke member 274. The intermediate support structure 275 includes members that extend both between the lower yoke member 272 and the upper yoke member 274 and between the distal yoke member 278 and the pulse collector 277. The intermediate support structure 275 is configured to prevent undesired collapse of the filter bag 250 during filtration of particulate matter from the polluted air being channeled into the dirty air chamber where the filter bag assembly 240 / 250 is disposed over the yoke assembly 270. The illustrated exemplary embodiment of the yoke assembly 270 also includes an intermediate yoke member 273 that extends from the pulse collector 277 to the distal yoke member 278, which can provide additional structural integrity to the yoke assembly 270 and support for the intermediate support structure 275.

[0096] The illustrated exemplary embodiment of the yoke assembly 270 is stationary and fixed within the dirty air chamber of the air filter system, and the filter bag assembly 240 / 250 is configured to mount over the yoke assembly 270 such that the yoke assembly 270 is disposed substantially within the interior volume of the filter bag 250 mounted to the service frame 240. As a result, removal of the filter bag assembly 240 / 250 for replacement of the filter bag 250 requires only removal of the service frame 240 and the filter bag 250, leaving the yoke assembly 270 in place within the dirty air chamber of the air filter system. Such a configuration results in a filter bag assembly 240 / 250 that is significantly reduced in weight as compared to filter bag assemblies in air filter systems in which the yoke assembly or at least an intermediate support structure is removed from the dirty air chamber along with the filter bag assembly during replacement of the filter bag.

[0097] 5 is an enlarged cross-sectional view (taken at line 5-5 in FIG. 3) of the filter bag assembly 240 / 250 and yoke assembly 270 of FIG. 4 assembled to a receiver 230 attached to a tube sheet 220 in one exemplary embodiment of an air filter system described herein. The receiver 230 includes a wall 232 surrounding an opening 221 in the tube sheet 220. The wall 232 of the receiver 230 includes an internal sealing surface 233. Also mounted within the opening 221 in the tube sheet 220 is a yoke assembly 270 including a pulse collector 277, a lower yoke member 272 and an intermediate support structure 275 of the yoke assembly 270.

[0098] Pulse collector 277 includes an opening 279 through which air may enter and exit the interior volume of filter bag 250. It is understood that pulse collector 277 is optional and may or may not be included in one or more embodiments of the air filter system and filter bag assemblies used therein. For example, in one or more embodiments, receiver 230 may function as a pulse collector.

[0099] 5 illustrates the interrelationship between the filter bag assembly 240 / 250, the receiver 230, and the yoke assembly 270. The illustrated exemplary embodiment of the filter bag assembly 240 / 250 includes a filter bag 250 mounted to the service frame 240 as described herein, for example as seen in FIGS. 3-4. In the cross-sectional view of FIG. 5, only the support ring 246 of the service frame 240 is visible. The support ring 246 has an outer surface 245 that faces the internal sealing surface 233 of the receiver 230 when the filter bag assembly 240 / 250 is in its operational position relative to the receiver 230 and yoke assembly 270.

[0100] The pocket gasket 260 in the filter bag 250 is also seen in the cross-sectional view of Figure 5. The illustrated embodiment of the pocket gasket 260 includes an inner member 262 and an outer member 264 that is attached to the outer surface of the inner member 262 at a location between the edges of the inner member 262 of the pocket gasket 260. The pocket gasket 260 includes a pocket 263 formed between the inner member 262 and the outer member 264, with the front edge 247 of the support ring 246 disposed within the pocket 263. Although not shown in Figure 5, the extension struts 242, 244 of the service frame 240 of the filter bag assembly 240 / 250 extend away from the tube sheet 220 towards an access panel of the air filter system in which the components shown in Figure 5 are located.

[0101] The pocket gasket 260 is attached to the filter sheet material of the filter bag 250 at a seam 250 / 260, which in the illustrated embodiment is located forward of the pocket 263 of the pocket gasket 260 and the front edge 247 of the support ring 246. For proper operation of the air filter system, the seam 250 / 260 at which the pocket gasket 260 is attached to the filter bag 250 prevents air from entering or leaving the interior volume of the filter bag 250 through the joint between the pocket gasket 260 and the filter bag 250 at the bag opening. Suitable attachment methods used at the joint between the filter bag 250 and the pocket gasket 260 include one or more of, but are not limited to, sewing, adhesives, tape, heat welding, chemical welding, and the like.

[0102] In the illustrated exemplary embodiment, the outer member 264 of the pocket gasket 260 defines an inner surface 265 that is attached to the support ring 246 such that the inner surface 265 forms a seal with the outer surface 245 of the support ring 246. As a result, when the pocket gasket 260 is properly attached to the support ring 246, air is prevented from passing through the interface between the outer member 264 of the pocket gasket 260 and the support ring 246.

[0103] In addition to forming a seal with the support ring 246, the pocket gasket also forms a seal with the interior sealing surface 233 of the receiver 230. In the illustrated exemplary embodiment, the pocket gasket 260 includes one or more fins 266 extending outwardly from the outer member 264 of the pocket gasket 260. The fins 266 interact with the interior sealing surface 233 of the receiver 230 to form a radial seal between the sealing surface 233 of the receiver 230 and the pocket gasket 260 such that air passing through the openings 221 in the tube sheet 220 must pass through the filter bag 250 as it passes through the openings 221 into or out of the contaminated air chamber. In one or more embodiments, the fins 266 may preferably extend continuously around the circumference of the outer portion 264 of the pocket gasket 260.

[0104] In one or more embodiments of the pocket gasket used in the filter bag assemblies described herein, the pocket gasket can be described as being compressed between the support ring and the sealing surface of the receiver. With respect to the components shown in FIG. 5, the pocket gasket 260 includes fins 266 that are compressed between the support ring 246 and the sealing surface 233 of the receiver 230, where in the embodiment shown, the compression is in the form of a flexing or deformation of the fins 266 upon advancing the pocket gasket 260 into the receiver 230 along the filter bag axis 211. Many other compressible and / or flexible structures can be substituted for the fins when forming a radial compression seal as described herein, and thus the fins are merely one example of a structure that can be used to form a compression seal between the support ring 246 and the receiver 230 as described herein.

[0105] In one or more embodiments, the location of the radial seal formed between the sealing surface 233 at the receiver 230 and the support ring 246 can be described as being located between a leading edge 247 of the support ring 246 and a trailing edge 249 of the support ring 246, where the trailing edge 249 of the support ring 246 is shown in FIG. 5 .

[0106] Another exemplary embodiment of a filter bag assembly including a filter bag 350 assembled to a receiver 330 attached to a tube sheet 320 and a service frame of an air filter system described herein is shown in an enlarged cross-sectional view in Figure 6 (taken on a line similar to line 5-5 in Figure 3). The same components are shown in another cross-sectional view in Figure 7 near one end of opening 321 in tube sheet 320, taken on line 7-7 in Figure 6.

[0107] In the embodiment shown, receiver 330 includes a wall 332 that surrounds opening 321 in tubesheet 320. Wall 332 of receiver 330 includes an internal sealing surface 333. Also mounted within opening 321 in tubesheet 320 is a yoke assembly that includes a pulse collector 377, lower yoke member 372 in FIG. 6 and upper yoke member 374 in FIG. 6, and a portion of yoke assembly intermediate support structure 375 in both FIGS. 6 and 7.

[0108] Pulse collector 377 includes an opening 379 through which air enters and exits the interior volume of filter bag 350. It is understood that pulse collector 377 is optional and may or may not be included in one or more embodiments of the air filter system and filter bag assemblies used therein.

[0109] One difference between receptacle 330 of Figures 6-7 and receptacle 230 of Figure 5 is that receptacle 230 of Figure 5 is disposed within the clean air chamber of an air filtration system described herein where tube sheet 220 separates the dirty air chamber and the clean air chamber in which filter bag 250 is disposed. Receptacle 330 of Figures 6-7, however, is disposed within the dirty air chamber of an air filtration system described herein where tube sheet 320 separates the dirty air chamber and the clean air chamber in which filter bag 350 is disposed.

[0110] 6-7 show the interrelationship between the service frame's support ring 346 and the receiver 330 and filter bag 350 with the yoke assembly. In the cross-sectional view of FIG. 6, only the service frame's support ring 346 is visible, while both the support ring 346 and the extension struts 344 are shown in FIG. 7. The support ring 346 has an outer surface 345 that faces the inner sealing surface 333 of the receiver 330 when the service frame's support ring 346 and extension struts 344 and the filter bag 350 with pocket gasket 360 are in their operative positions relative to the receiver 330 and yoke assembly (represented by upper yoke member 372, lower yoke member 374, middle yoke member 373, middle support structure 375, and pulse collector 377).

[0111] In one or more embodiments of a service frame including an extension post and a support ring, such as extension post 344 and support ring 346 shown in FIG. 7, the extension post can be attached to the support ring by any suitable method or combination of methods, such as, but not limited to, welding, mechanical fasteners, adhesives, etc.

[0112] The embodiment of the pocket gasket 360 in the illustrated filter bag 350 includes an inner member 362 and an outer member 364 attached to the outer surface of the inner member 362 at a location between the edges of the inner member 362 of the pocket gasket 360. The pocket gasket 360 includes a pocket 363 formed between the inner member 362 and the outer member 364, with the front edge 347 of the support ring 346 disposed within the pocket 363. The extension struts of the service frame (only a portion of the extension struts 344 are shown in FIG. 7) extend away from the tube sheet 320 toward an access panel of the air filter system in which the components shown in FIGS. 6 and 7 are located.

[0113] The pocket gasket 360 is attached to the filter sheet material of the filter bag 350 at a seam 350 / 360, which in the illustrated embodiment is located forward of the pocket 363 of the pocket gasket 360 and the front edge 347 of the support ring 346. For proper operation of the air filter system, the seam 350 / 360 at which the pocket gasket 360 is attached to the filter bag 350 prevents air from entering or leaving the interior volume of the filter bag 350 through the joint between the pocket gasket 360 and the filter bag 350 at the bag opening. Suitable attachment methods used at the joint between the filter bag 350 and the pocket gasket 360 include one or more of, but are not limited to, sewing, adhesives, tape, heat welding, chemical welding, and the like.

[0114] In the illustrated exemplary embodiment, the outer member 364 of the pocket gasket 360 defines an inner surface 365 that is attached to the support ring 346 such that the inner surface 365 forms a seal with the outer surface 345 of the support ring 346 (these surfaces are designated 345 / 365 in FIGS. 6 and 7). As a result, when the pocket gasket 360 is properly attached to the support ring 346, air is prevented from passing through the interface between the outer member 364 of the pocket gasket 360 and the support ring 346.

[0115] In addition to forming a seal with the support ring 346, the pocket gasket 360 also forms a seal with the interior sealing surface 333 of the receiver 330. In the illustrated exemplary embodiment, the pocket gasket 360 includes one or more fins 366 extending outwardly from an outer member 364 of the pocket gasket 360. The fins 366 interact with the interior sealing surface 333 of the receiver 330 to form a radial seal between the sealing surface 333 of the receiver 330 and the pocket gasket 360 such that air passing through the openings 321 in the tube sheet 320 must pass through the filter bag 350 as it passes through the openings 321 into or out of the contaminated air chamber. In one or more embodiments, the fins 366 may preferably extend continuously around the circumference of the outer portion 364 of the pocket gasket 360.

[0116] As discussed with respect to the exemplary embodiment shown in FIG. 5, in one or more embodiments of the pocket gasket used in the filter bag assemblies described herein, the pocket gasket can be described as being compressed between the support ring and the sealing surface of the receiver. With respect to the components shown in FIGS. 6-7, the pocket gasket 360 includes fins 366 that are compressed between the support ring 346 and the sealing surface 333 of the receiver 330, where in the illustrated embodiment, the compression is in the form of a flexure or deformation of the fins 366 upon advancing the pocket gasket 360 into the receiver 330 along the filter bag axis 311. As also discussed above, many other structures can be substituted for fins when forming a radial compression seal as described herein, and thus the fins are merely one example of a structure that can be used to form a compression seal between a support ring and a receiver using a pocket gasket as described herein.

[0117] In the illustrated exemplary embodiment, the location of the radial seal formed by the pocket gasket 360 between the sealing surface 333 at the receiver 330 and the support ring 346 can be described as being located between the leading edge 347 of the support ring 346 and the trailing edge 349 of the support ring 346.

[0118] Yet another exemplary embodiment of a filter bag assembly including a filter bag 450 assembled to a receiver 430 attached to a tube sheet 420 of an air filter system described herein and a service frame is shown in an enlarged cross-sectional view of Figure 8 (taken on a line similar to line 5-5 of Figure 3). The same components are shown in another cross-sectional view of Figure 9 near one end of opening 421 in tube sheet 420, taken on line 9-9 of Figure 8.

[0119] In the embodiment shown, receiver 430 includes a wall 432 that surrounds opening 421 in tubesheet 420. Wall 432 of receiver 430 includes an internal sealing surface 433. Also mounted within opening 421 in tubesheet 420 is a yoke assembly that includes a pulse collector 477, lower yoke member 472 and intermediate yoke member 473 in FIG. 8, upper yoke member 474 in FIG. 9, and a portion of intermediate support structure 475 for the yoke assembly in both FIGS. 8 and 9.

[0120] Pulse collector 477 includes an opening 479 through which air enters and leaves the interior volume of filter bag 450. It is understood that pulse collector 477 is optional and may or may not be included in one or more embodiments of the air filter system and filter bag assembly used therein.

[0121] 8 and 9 show the interrelationship between the support ring 446 of the service frame and the filter bag 450 with the receiver 430 and yoke assembly. The support ring 446 has an outer surface 445 that faces the internal sealing surface 433 of the receiver 430 when the support ring 446 and extension struts 444 of the service frame and the filter bag 450 including the pocket gasket 460 are in their operating positions relative to the receiver 430 and yoke assembly (represented by upper yoke member 472, lower yoke member 474, middle yoke member 473, middle support structure 475, and pulse collector 477). As shown in FIG. 9, the extension struts 444 are disposed within the channel formed by the upper yoke member 474 such that the service frame's extension struts 444 are disposed within the internal volume of the filter bag 450 (as are the other components of the service frame).

[0122] The illustrated embodiment of the pocket gasket 460 in the filter bag 450 has a different structure than the pocket gaskets 260 and 360 described above. The illustrated embodiment of the pocket gasket 460 includes an inner member 462 and an outer member 464 attached to the inner member 462. However, the inner member 462 is located between the outer member 464 and the support ring 446. In one manner of characterizing the arrangement of the inner member 462 and the outer member 464, the inner member 462 can be described as being folded under the outer member 464. In any event, the inner member 462 and the outer member 464 form a pocket 463, with the front edge 447 of the support ring 446 disposed within the pocket 463.

[0123] The pocket gasket 460 is attached to the filter sheet material of the filter bag 450 at a seam 450 / 460, which in the illustrated embodiment is located forward of the pocket 463 of the pocket gasket 460 and the front edge 447 of the support ring 446. For proper operation of the air filter system, the seam 450 / 460 at which the pocket gasket 460 is attached to the filter bag 450 prevents air from entering or leaving the interior volume of the filter bag 450 through the joint between the pocket gasket 460 and the filter bag 450. Suitable attachment methods used at the joint between the filter bag 450 and the pocket gasket 460 include, but are not limited to, one or more of sewing, adhesives, tape, heat welding, chemical welding, and the like.

[0124] In addition to forming a seal with the support ring 446, the pocket gasket 460 also forms a seal with the interior sealing surface 433 of the receiver 430. In the illustrated exemplary embodiment, the pocket gasket 460 includes one or more fins 466 extending outwardly from an outer member 464 of the pocket gasket 460. The fins 466 interact with the interior sealing surface 433 of the receiver 430 to form a radial seal between the sealing surface 433 of the receiver 430 and the pocket gasket 460 such that air passing through the openings 421 in the tube sheet 420 must pass through the filter bag 450 as it passes through the openings 421 into or out of the contaminated air chamber. In one or more embodiments, the fins 466 may preferably extend continuously around the periphery of the outer portion 464 of the pocket gasket 460.

[0125] As discussed with respect to the exemplary embodiment shown in Figures 5-7, in one or more embodiments of the pocket gasket used in the filter bag assemblies described herein, the pocket gasket can be described as being compressed between the support ring and the sealing surface of the receiver. With respect to the components shown in Figures 8-9, the pocket gasket 460 includes fins 466 that are compressed between the support ring 446 and the sealing surface 433 of the receiver 430, where in the illustrated embodiment, the compression is in the form of a deflection or deformation of the fins 466 upon advancing the pocket gasket 460 into the receiver 430 along the filter bag axis 411. As also discussed above, many other structures can be substituted for the fins when forming a radial compression seal as described herein, and thus the fins are merely one example of a structure that can be used to form a compression seal between the support ring and the receiver using a pocket gasket as described herein.

[0126] In the illustrated exemplary embodiment, the location of the radial seal formed by the pocket gasket 460 between the sealing surface 433 at the receiver 430 and the support ring 446 can be described as being located between the leading edge 447 of the support ring 446 and the trailing edge 449 of the support ring 446.

[0127] All of the exemplary embodiments of the pocket gasket provided at the bag opening of the filter bag described above with respect to Figures 5-9 involve compression of the pocket gasket between the support ring and the sealing surface of the receiver, and the support ring and pocket of the pocket gasket are positioned within the receiver such that they are formed within the receiver and the outer surface of the support ring.

[0128] Another exemplary embodiment of a filter bag assembly 540 / 550 is shown in Figure 10 where a pocket gasket 560 attached to the filter bag 550 at the bag opening forms a radial seal with a receiver 530 attached to the tubesheet 520. In contrast to the pocket gasket shown with respect to Figures 5-9 where both the support ring and the pocket of the pocket gasket are disposed within the receiver such that the pocket gasket is compressed between the support ring and the sealing surfaces of the receiver, the receiver 530 has an outer surface disposed within the pocket gasket 560.

[0129] 10 includes a closed end 556 located distally from a bag opening located within a pocket gasket 560. As a result, the filter bag 550 also defines a filter bag axis 511 that extends between the filter bag opening (represented by the pocket gasket 560) and the closed end 556 of the filter bag 550.

[0130] 11-12 illustrate another exemplary embodiment of the components of a filter bag assembly described herein, with FIG. 11 illustrating a service frame 640 and FIG. 12 illustrating a filter bag 650. The service frame 640 shown in FIG. 11 includes a support ring 646, a pair of extension struts 642, 644 attached to the support ring 646, and a distal end strut 648 attached to the extension struts 642, 644. The support ring 646 includes a front edge 647 facing away from or distal to the distal end strut 648 and a rear edge 649 facing toward or proximal to the distal end strut 648 such that the rear edge 649 of the support ring 646 is disposed between the front edge 647 and the distal end strut 648.

[0131] One difference between the service frame 640 shown in FIG. 11 and the service frame partially shown in FIG. 7 is that the extension posts 344 in FIG. 7 are attached to the outer surface 345 of the support ring 346, whereas in the embodiment of the service frame 640 shown in FIG. 11, the extension posts 642, 644 are attached to the inner surface of the support ring 646.

[0132] 12, the filter bag 650 includes a body 652 having a filter bag opening 654 and a closed end 656 distally located from the filter bag opening 654, with the filter bag axis 611 extending between the filter bag opening 654 and the closed end 656. A pocket gasket 660 is attached to the filter bag 650 at the bag opening 654.

[0133] When assembled to form a filter bag assembly, the service frame 640 is positioned within the interior volume defined by the body 652 of the filter bag 650 and the pocket gasket 660 is engaged with the support ring 646 of the service frame 640 .

[0134] 13-17 show a forward portion of the filter bag assembly 540 / 550 disposed on the yoke assembly 570 extending away from the tube sheet 520 to which the receiver 530 is attached. The filter bag assembly 540 / 550 has not yet engaged with the receiver 530. In other words, the pocket gasket 560 on the filter bag 550 has not yet engaged with the receiver 530 to form a radial seal between the pocket gasket 560 and the receiver 530 as described herein.

[0135] In the illustrated embodiment, the yoke assembly 570 includes an upper yoke member 572 and a lower yoke member 574, with an intermediate support structure 575 extending between the upper yoke member 572 and the lower yoke member 574. As described herein, the intermediate structure included in the yoke assembly can be useful in preventing the filter bag 550 from collapsing during filtering of particulate matter from contaminated air.

[0136] 14, a forward portion of the service frame 540, including the extension struts 542 and the support ring 546, is shown in combination with a yoke assembly 570. The yoke assembly 570 includes an upper yoke member 572 and an intermediate support structure 575. The upper yoke member 572 includes strut channels 579 into which the extension struts 542 of the service frame 540 are at least partially received. This configuration may aid in the movement of the service frame 540 on the yoke assembly 570. In particular, when at least one extension strut (e.g., extension strut 542) is located within a strut channel in one of the yoke members of the yoke assembly 570, proper alignment of a pocket gasket on a filter bag held by the service frame 540 may be improved during forwarding of the service frame 540 on the yoke assembly 570 toward the receiver 530 and the tube sheet 520.

[0137] 14 also provides a better view of the arrangement of the extension struts 542 within the support ring 546. The support ring 546 includes a leading edge 547 and a trailing edge 549 as described herein.

[0138] 15, filter bag assembly 540 / 550 has been assembled and partially advanced into yoke assembly 570 as described herein. Features shown in FIG. 15 not visible in FIGS. 13 and 14 include opening 521 in tube sheet 520 with receiver 530 disposed about opening 521 (note that in FIG. 15 only a portion of receiver 530 is visible through opening 521 in tube sheet 520). Advancement of filter bag assembly 540 / 550, including pocket gasket 560 attached to the bag opening of filter bag 550, is aided by strut channel 579 in upper yoke member 572 which receives extension strut 542 attached to support ring 546 as shown in FIG. 14, for example, as described above.

[0139] FIG 16 is a cross-sectional view of a perspective view of the filter bag assembly 540 / 550, yoke assembly 570, tube sheet 520, and receiver 530 shown in FIG 13, while FIG 17 shows the filter bag assembly 540 / 550 after advancing the pocket seal 560 into the receiver 530 attached to the tube sheet 520 about the opening 521 in the tube sheet 520. Features shown in FIG 16-17 include a sealing surface 533 on the outside of the receiver 530 attached to the tube sheet 520 about the opening 521 in the tube sheet 520. Also shown in FIG 16-17 is a forward edge 567 of the pocket gasket 560, which is located distally from the closed end (not shown) of the filter bag 550 along the filter bag axis 511. 16-17 also show a rear edge 569 of the pocket gasket 560, which is located between the forward edge 567 of the pocket gasket 560 and the closed end of the filter bag 550 (not shown).

[0140] 17, the pocket gasket 560 includes a pocket 563, and a front edge 547 of the support ring 546 is disposed within the pocket 563 adjacent the tube sheet 520. The pocket gasket 560 is attached to the filter sheet material of the filter bag 550 at a seam 550 / 560, which in the illustrated embodiment is located between the pocket 563 and a rear edge 569 of the pocket gasket 560. For proper operation of the air filter system, the seam 550 / 560 at which the pocket gasket 560 is attached to the filter bag 550 prevents air from entering or leaving the interior volume of the filter bag 550 through the joint between the pocket gasket 560 and the filter bag 550 at the seam 550 / 560. Suitable attachment methods used at the joint between the filter bag 550 and the pocket gasket 560 include, but are not limited to, one or more of sewing, adhesives, tape, heat welding, chemical welding, and the like.

[0141] In addition to forming a seal with the support ring 546, the pocket gasket 560 also forms a seal with the exterior sealing surface 533 of the receiver 530. In the illustrated exemplary embodiment, the pocket gasket 560 includes one or more fins 566 extending inwardly from the pocket gasket 560. The fins 566 interact with the exterior sealing surface 533 of the receiver 530 to form a radial seal between the sealing surface 533 of the receiver 530 and the pocket gasket 560 such that air passing through the openings 521 in the tube sheet 520 must pass through the filter bag 550 as it passes through the openings 521 into or out of the contaminated air chamber. In one or more embodiments, the fins 566 may preferably extend continuously around the periphery of the inner surface of the pocket gasket 560.

[0142] In the illustrated exemplary embodiment, the location of the radial seal formed by the pocket gasket 560 with the sealing surface 533 at the receiver 530 can be described as being located between the forward edge 547 of the support ring 546 (and / or pocket 563) and the forward edge 567 of the pocket gasket 560.

[0143] In one or more embodiments, the fins 566 in the pocket gasket 560 can be described as being compressed as the pocket gasket 560 is advanced along the filter bag axis 511 into the receiver 530, the compression resulting in a deflection or deformation of the fins 566. As described herein, many other structures can be substituted for the fins that form a radial seal as described herein, and thus the fins are only one example of a structure that can be used to form a radial seal between the pocket gasket and a receiver disposed within the pocket gasket.

[0144] Yet another exemplary embodiment of a filter bag assembly is shown in Figures 18-20B. The filter bag is not shown in Figures 18-20B, exposing components that are located within the filter bag and therefore not normally visible by the filter bag. However, the filter bag is attached to the pocket gasket 760 at region 761 of the pocket gasket 760 by any suitable method or combination of methods, such as, but not limited to, sewing, adhesive, tape, heat welding, chemical welding, etc., as described herein.

[0145] 19-20B, the receiver 730 is disposed within a pocket gasket 760 adjacent to the tube sheet 720 (similar to the arrangement of the receiver 530 located within the pocket gasket 560 as shown in the embodiment of FIGS. 10, 13, and 17).

[0146] 18, the filter bag assembly includes a service frame 740 having a pair of extension struts 742, 744 attached to a support ring 746 (which is disposed within a pocket gasket 760 as shown in FIGS. 20A-20B). The extension struts 742, 744 extend from the support ring 746 to a distal end strut 748, which is typically disposed at or near the closed end of the filter bag that is attached to the pocket gasket 760.

[0147] 20B, the support ring 746 includes a leading edge 747 that faces away from or distal to the distal posts 748 and a trailing edge 749 that faces toward or proximal to the distal posts 748 such that the trailing edge 749 of the support ring 746 is disposed between the leading edge 747 of the support ring 746 and the distal posts 748. In the embodiment shown in FIGS. 18-20B, the extension posts 742, 744 are attached to the support ring 746 adjacent the trailing edge 749 of the support ring 746.

[0148] 19, a pocket gasket 760 is shown attached to a receiver 730 that is attached to a tube sheet 720. As shown in Figures 20A and 20B, the receiver 730 is disposed within an opening 721 in the tube sheet 720. As described herein with respect to other embodiments, the opening 721 allows for the passage of clean air out of the interior volume of the filter bag and the passage of a cleaning pulse into the interior volume of the filter bag for cleaning the filter bag.

[0149] 20A shows a top forward portion of the pocket gasket 760 and a service frame 740 disposed on a yoke assembly including an upper yoke member 772 and a lower yoke member 774 that extend away from the tube sheet 720 to which the receiver 730 is attached. The pocket gasket 760 engages the receiver 730 to form a radial seal between the pocket gasket 760 and the receiver 730, as described herein. In the illustrated embodiment, the yoke assembly includes an intermediate support structure 775 that extends between the upper yoke member 772 and the lower yoke member 774. As described herein, the intermediate structure included in the yoke assembly can be useful in preventing the filter bag from collapsing during filtering of particulate matter from contaminated air.

[0150] Additionally, each of the yoke members 772 / 774 of the yoke assembly shown in Figures 18-20B preferably includes a support channel such that the extension posts 742, 744 are at least partially received within the support channel when a service frame including the extension posts 742, 744 is attached to the yoke assembly with the pocket gasket 760 engaged with the receivers 730 in the tube sheet 720. As described herein, providing support channels to receive the extension posts of the service frame helps to stabilize and align the entire filter bag assembly and can support the weight of the filter bag assembly as it moves toward or away from the tube sheet 720 during bag replacement.

[0151] 20A and 20B, there is shown the arrangement of the extension struts 742 within the strut channels 779 of the upper yoke member 772. A similar arrangement may be provided for the extension struts 744 and lower yoke member 774, however, in one or more embodiments, having only one yoke member with a strut channel can provide the advantages described herein.

[0152] Figure 20A is an enlarged cross-sectional view of the top of the assembly of Figure 18 taken at line 20-20 of Figure 18. Figure 20B is further enlarged to show additional features of the assembly when pocket gasket 760 is engaged with receiver 730 attached to tubesheet 720 around opening 721 in tubesheet 720. Features shown in Figures 20A-20B include sealing surface 733 on the outside of receiver 730.

[0153] The pocket gasket 760 includes a pocket 763, and a leading edge 747 of the support ring 746 is disposed within the pocket 763 adjacent the tube sheet 720. The pocket gasket 760 is attached to the filter sheet material of the filter bag at a seam located along a trailing edge 761 of the pocket gasket 760. For proper operation of the air filter system, the attachment between the pocket gasket 760 and the filter bag prevents air from entering or leaving the interior volume of the filter bag through the juncture between the pocket gasket 760 and the filter bag at the seam area 761.

[0154] In addition to forming a seal with the support ring 746, the pocket gasket 760 also forms a seal with the exterior sealing surface 733 of the receiver 730. In the illustrated exemplary embodiment, the pocket gasket 760 includes one or more fins 766 extending inwardly from the pocket gasket 760. The fins 766 interact with the exterior sealing surface 733 of the receiver 730 to form a radial seal between the sealing surface 733 of the receiver 730 and the pocket gasket 760 such that air passing through the openings 721 in the tube sheet 720 must pass through a filter bag attached to the pocket gasket 760 as it passes through the openings 721 into or out of the contaminated air chamber. In one or more embodiments, the fins 766 may preferably extend continuously around the interior surface of the pocket gasket 760 and the exterior surface 733 of the receiver 730.

[0155] In the illustrated exemplary embodiment, the location of the radial seal formed by the pocket gasket 760 with the sealing surface 733 at the receiver 730 can be described as being located between the leading edge 747 of the support ring 746 (and / or the pocket 763) and the trailing edge 749 of the support ring 746.

[0156] In one or more embodiments, the fins 766 in the pocket gasket 760 can be described as being compressed as the pocket gasket 760 is advanced along the filter bag axis 711 into the receiver 730, the compression resulting in a deflection or deformation of the fins 766. As described herein, many other structures can be substituted for the fins that form a radial seal as described herein, and thus the fins are only one example of a structure that can be used to form a radial seal between the pocket gasket and a receiver disposed within the pocket gasket.

[0157] Also shown in Figures 20A-20B is a forward edge 767 of the pocket gasket 760. As shown in Figures 19-20B, the forward edge 767 is spaced from the tube sheet 720. In one or more embodiments, such spacing of the forward edge 767 of the pocket gasket 760 may be acceptable because the seal between the receiver 730 and the pocket gasket is formed between the support ring 746 and the sealing surface 733 of the receiver 730. This is in contrast to systems that form an axial seal in which the forward edge 767 of the pocket gasket 760 is forced against the tube sheet in the direction of the filter bag axis 711 to form a seal at that juncture.

[0158] 21A-21F illustrate another optional feature that may be provided with respect to one or more embodiments of the filter bag assemblies described herein in the form of a retention tab extending from a front edge of the support ring and a corresponding tab opening in the gasket configured to receive the retention tab.

[0159] The retention tabs, in one or more embodiments, are provided to restrain the gasket from rotating or twisting as the gasket is inserted into or over the receiver as described herein. Any tendency for the gasket to roll during installation into or over the receiver can be restrained by the interlocking relationship / mechanical interference provided by the retention tabs and tab openings without adversely affecting the ability of the gasket and receiver to form a seal necessary for proper operation as described herein. In one or more embodiments, the tab openings extend through the gasket from the pocket that receives the support ring, through the forward edge of the pocket gasket, such that the retention tabs are exposed at the forward edge of the pocket gasket. In one or more embodiments, the tab openings can be described as extending through the gasket from the forward end of the pocket, through the forward edge of the gasket, and through the gasket.

[0160] 21A , the support ring 2546 is attached to an extension strut 2542 of the service frame which in turn is disposed within a channel of the yoke member 2572 as described herein with respect to other exemplary embodiments of the filter bag assemblies and filter systems. The support ring 2546 includes a front edge 2547 on which a retention tab 2549 is disposed. The retention tab 2549 projects from the front edge 2547 of the support ring 2546 along a bag axis 2511 which extends through the support ring and service frame, in a direction away from the distal end of the service frame / closed end of the bag attached to the service frame.

[0161] 21B, the gasket 2560 and filter bag 2550 are mounted to the service frame of FIG. 21A and the support ring 2546 is placed into a pocket formed in the gasket 2560 as described herein with respect to similar exemplary embodiments of a filter bag assembly. The gasket 2560 includes a tab opening 2569 that receives a retention tab 2549. In one or more embodiments, the retention tab 2549 can preferably extend through the tab opening such that it extends beyond the front edge 2568 of the gasket 2560. The interlocking arrangement of the retention tab 2549 and tab opening 2569 prevents the gasket 2560 from rolling over the front edge 2547 of the support ring 2546 when the gasket 2560 and support ring are mounted in or over a receiver as described herein.

[0162] FIG 21C shows the assembly of the gasket 2560 and support ring 2546 in the receiver 2530. FIG 21C shows a view from the tubesheet side of the receiver 2530 with the tubesheet removed to expose the gasket 2560 within the receiver 2530. The exemplary embodiment of the receiver 2530 shown includes optional relief openings 2532 that are sized and positioned to receive the retention tabs 2549 to allow advancement of the gasket 2560 (and support ring 2546) into the receiver 2530 without interference from the retention tabs 2549.

[0163] Although Figures 21A-21C show one pair of retention tabs and corresponding tab openings, it will be understood that any suitable number of retention tabs and corresponding openings may be provided as needed to improve retention of the gasket of the filter bag on the support ring, as described herein.

[0164] 21D is a close-up view of the retention tab 2549 mating with the tab opening 2569 of the gasket 2560 (the filter bag shaft 2511 is provided for reference). In one or more embodiments, the retention tab 2549 extends through the tab opening such that the retention tab 2549 extends beyond the forward edge 2568 of the gasket 2560. Although not required, having the tab extend beyond the forward edge 2568 of the gasket 2560 can improve retention of the gasket with the support ring 2546.

[0165] 21E illustrates another example embodiment of one of the retention tabs 2549-1 on the support ring 2546-1, where the retention tab 2549-1 includes an enlarged head that is larger than the tab opening 2569-1 provided in the gasket 2560-1. Stretching of the gasket 2560-1 during insertion of the retention tab 2549-1 into the tab opening 2569-1 can improve retention of the gasket 2560-1 on the support ring 2546-1.

[0166] 21F illustrates another example embodiment of the retention tabs 2549-2 on the support ring 2546-2, where the retention tabs 2549-2 are inverted wedge shaped and larger than the tab openings 2569-2 provided in the gasket 2560-2. Stretching of the gasket 2560-2 during insertion of the retention tabs 2549-2 into the tab openings 2569-2 can improve retention of the gasket 2560-2 on the support ring 2546-2.

[0167] Yet another exemplary embodiment of a filter bag assembly is shown in Figures 22-27. The filter bag assembly is inserted into a receiver 830 that is attached to a tube sheet 820. An opening 821 is formed through the tube sheet 820 and an optional pulse collector 877 is located within the opening 821. The pulse collector 877 provides a path for the passage of clean air out of the interior volume of the filter bag 850, as described herein with respect to other embodiments, and for the passage of a cleaning pulse into the interior volume of the filter bag for cleaning the filter bag, also as described herein.

[0168] The filter bag assembly includes a filter bag having a tubular body 850 that extends from a bag opening to a closed end 856. In the illustrated embodiment, the bag opening is disposed within a gasket 860 that is located opposite the closed end 856 of the filter bag 850 along the filter bag axis 811. As described above with respect to the other embodiments of the filter bag assembly, the gasket 860 extends around and is attached to the periphery of the bag opening.

[0169] The illustrated filter bag assembly also includes a service frame that includes a pair of extension struts 842, 844 that extend from a support ring 846 to a distal end strut 848 that is disposed at or near a closed end 856 of a filter bag 850 that is attached to a gasket 860.

[0170] The illustrated embodiment of gasket 860 includes a sealing member 866 that extends around the periphery of gasket 860 and forms a seal with a sealing surface 833 located within receiver 830. Sealing member 866 may be comprised of any suitable compressible material, such as, for example, a foamed elastomer, loose felt, piled / fuzzed gasket material, a solid elastomer, or the like.

[0171] For example, with reference to Figures 26-27, the illustrated gasket 860 embodiment includes a gasket frame 867 to which a seal member 866 is attached. The gasket frame 867 also defines a pocket 863 that receives the support ring 846 of the service frame. In the illustrated exemplary embodiment, the gasket frame 867 also forms a connection with the bag opening of the filter bag 850. With particular reference to Figure 27, a portion 851 of the filter bag 850 proximate the filter bag opening may be molded into the gasket frame 867 of the gasket 860 or may be otherwise attached to the gasket frame 867. Other methods that may be used to attach the filter bag 852 to the frame 867 of the gasket 860 may include, for example, one or more of adhesives, sewing, clamps, and the like.

[0172] The gasket frame 867, in one or more embodiments, can be constructed of a material that is more rigid than the material used for the seal members, such as a rigid composite, an engineering plastic, a rigid plastic, a metal (e.g., a cast metal, etc.), etc.

[0173] 27, gasket 860 can be described as having an outer surface 861 that faces away from the filter bag axis (see, e.g., filter bag axis 811 in FIG. 23), which extends around the periphery of gasket 860. Gasket 860 can be further described as having an inner surface 862 that faces the filter bag axis, which also extends around the periphery of gasket 860. Although not specifically shown in the various figures, gaskets included in other exemplary embodiments of the filter bags described herein also include similar inner and outer surfaces as those described with respect to gasket 860.

[0174] 23, the gasket 860 can also be described as having a forward edge 864 that is located distally from the closed end 856 of the tubular body of the filter bag 850. The gasket 860 can further be described as having a trailing edge 865. The trailing edge 865 is disposed between the forward edge 864 and the closed end 856 of the tubular body of the filter bag 850.

[0175] The illustrated exemplary embodiment of gasket 860 also includes a pocket 863 formed therein. Pocket 863 is located between exterior surface 861 and interior surface 862. Pocket 863 includes a pocket opening 869 through which a support ring (e.g., support ring 846) can be inserted into pocket 863. Pocket 863 also includes a forward end 868, which is located between pocket opening 869 and forward edge 864 of gasket 860. Pocket 863 is configured to receive a support ring, such as support ring 846, that extends around a bag opening of filter bag 850, as described herein.

[0176] In one or more embodiments, the pocket opening 869 can be described as an opening into the interior volume defined by the filter bag 850 .

[0177] In one or more embodiments, the pocket opening 869 can be described as facing the closed end 856 of the tubular body 850 .

[0178] In one or more embodiments, the pocket openings may be located closer to the front edge of the gasket and closer to the trailing edge of the gasket. One example of such a configuration can be seen, for example, in gasket 460 shown in FIG.

[0179] Another exemplary embodiment of a filter bag assembly is shown in Figures 28-31. The filter bag assembly shown in these figures includes a gasket 960 disposed in a receiver 930 attached to a tube sheet 920. An opening 921 is formed through the tube sheet 920 with an optional pulse collector 977 located within the opening 921. The pulse collector 977 provides a path for the passage of clean air out of the interior volume of the filter bag 950, as described herein with respect to other embodiments, and for the passage of a cleaning pulse into the interior volume of the filter bag for cleaning the filter bag, also as described herein.

[0180] The filter bag assembly includes a filter bag having a tubular body 950 that extends from a bag opening to a closed end (not shown). In the illustrated embodiment, the bag opening is disposed within a gasket 960 that is located opposite the closed end of the filter bag 950 along the filter bag axis 911. As described above with respect to the other embodiments of the filter bag assembly, the gasket 960 extends around and is attached around the bag opening.

[0181] The illustrated filter bag assembly also includes a service frame that includes a pair of extension struts 942, 944 that extend from a support ring 946 to a distal end strut (not shown) that is disposed at or near the closed end of a filter bag 950 that is attached to a gasket 960.

[0182] 30-31, for example, the illustrated embodiment of the gasket 960 includes a gasket frame 967 to which a seal member 966 is attached. The gasket frame 967 also defines a pocket 963 that receives the support ring 946 of the service frame. In the illustrated exemplary embodiment, the bag opening of the filter bag 950 is attached to the gasket frame 967 by any suitable method or combination of methods, such as, but not limited to, molding, adhesives, sewing, clamping, etc.

[0183] In the embodiment of gasket 960 shown, sealing member 966 is attached to an inner surface of gasket 960 and extends around an inner periphery of gasket 960. Sealing member 966 forms a seal with sealing surface 933 located on the outer surface of receiver 930, as seen, for example, in Figures 30-31. Sealing member 966 can be comprised of any suitable compressible material, such as, for example, a foamed elastomer, loose felt, piled / fuzzed gasket material, a solid elastomer, etc.

[0184] 32-1-32-4 show components of another exemplary embodiment of a filter bag and filter bag assembly described herein. The filter bag assembly includes a filter bag 950-1, shown in dashed lines to expose the components disposed within the filter bag. The filter bag 950-1 is in the form of a tubular body (e.g., envelope-shaped) that extends from a bag opening 954-1 to a closed end 958-1. As with the other filter bags described herein, the tubular body of the filter bag 950-1 is defined by a flexible filter sheet material that defines an interior volume of the filter bag 950-1 between the bag opening 954-1 and the closed end 958-1. The tubular body of the filter bag 950-1 defines a filter bag axis 911-1 that extends through the bag opening 954-1 and the closed end 958-1.

[0185] The gasket assembly is attached to the bag opening 954-1 of the tubular body of the filter bag 950-1, with the gasket assembly extending around and attached to the bag opening 954-1. An exemplary embodiment of the gasket assembly includes a support ring 946-1 and a gasket 960-1. The support ring 946-1 extends around the bag opening 954-1 and includes a front edge facing away from the closed end 958-1 of the tubular body of the filter bag 950-1.

[0186] The illustrated gasket assembly includes a gasket 960-1 attached to a support ring 946-1. The gasket 960-1 extends around the bag opening 954-1 and is configured to form a radial seal when a filter bag is attached to the dust collector and compressed against the support ring 946-1.

[0187] The gasket 960-1 of the example gasket assembly shown in FIGS. 32-1-32-4 is positioned on the outer surface of the support ring 946-1 with the gasket 960-1 facing away from the filter bag axis 911-1.

[0188] 32-1-3, the flexible filter sheet material that defines the interior volume of the filter bag 950-1 is attached to a gasket 960-1 of a gasket assembly. In particular, the sheet material that defines the bag opening 954-1 is attached to a flange 961-1 of the gasket 960-1 using any suitable method or combination of methods, such as sewing, adhesives, heat welding, chemical welding, etc.

[0189] 32-1-32-4, the illustrated embodiment of the filter bag assembly includes a service frame. The service frame includes a pair of extension struts 942-1, 944-1 that extend away from the gasket assembly and bag opening 954-1 toward the closed end 958-1 of the filter bag 950-1, where the extension struts 942-1, 944-1 are connected to each other by a distal end strut 948-1 that, in the illustrated embodiment, extends along the inside of the closed end 958-1 of the filter bag 950-1. As with the other embodiments described herein, the service frame supports the filter bag 950-1.

[0190] Support ring 946-1 includes a pair of pockets 947-1 on opposite ends of support ring 946-1, each configured to receive an end of an extension post 942-1 or 944-1 of the service frame.

[0191] 32-5, another exemplary embodiment of a gasket assembly including a support ring 946-2 and a gasket 960-2 is shown, the gasket assembly being disposed within a receiver 930-2. When so disposed, the gasket 960-2 is compressed between an outer surface of the support ring 946-2 and an inner surface of the receiver 930-2 to form a radial seal as described herein. When the receiver 930-2 is disposed in an opening in a tube sheet as described herein, the radial seal formed between the gasket 960-2 and the receiver 930-2 preferably prevents air and particulate matter from passing between the gasket 960-2 and the receiver 930-2.

[0192] 32-6, another exemplary embodiment of a gasket assembly including a support ring 946-23 and a gasket 960-23 is shown disposed in a receiver 930-23. When so disposed, the gasket 960-23 is compressed between an inner surface of the support ring 946-3 and an outer surface of the receiver 930-3 to form a radial seal as described herein. When the receiver 930-3 is disposed in an opening in a tube sheet as described herein, the radial seal formed between the gasket 960-3 and the receiver 930-3 preferably prevents air and particulate matter from passing between the gasket 960-3 and the receiver 930-3.

[0193] Although not shown in the embodiment of Figures 32-1 to 32-6, the front edge of the gasket assembly, e.g., the support ring, can be formed to securely fit into a correspondingly shaped receptacle, e.g., as described below with respect to Figures 33 to 35.

[0194] Potential advantages of a filter bag having a gasket assembly and a service frame configured to attach to the support ring of the gasket assembly include a simplified construction, which may result in a lighter filter bag assembly, facilitating insertion and removal of the filter bag assembly within the contaminated air chamber of the filter system, and may make it easier to adapt the service frame to filter bags of different lengths.

[0195] 33 illustrates an additional optional feature that may be found in one or more embodiments of an air filter system that uses a filter bag assembly including the filter bags described herein. The illustrated system includes a tube sheet 1022 with a receiver 1030 attached. A pulse collector 1077 is also attached to the tube sheet 1020 and / or receiver 1030 such that clean air exiting the interior of the filter bag 1050 can enter the clean air chamber side of the tube sheet 1020, and pulses of air or other gases directed into the pulse collector 1077 can be directed into the interior of the filter bag 1050 as described herein.

[0196] In the illustrated embodiment, the filter bag 1050 includes a gasket 1060 at its forward end, the gasket 1060 including a forward edge 1064 and a rearward edge 1065. The forward edge 1064 can be described as being located distally from a closed end (not shown) of the filter bag 1050, and the rearward edge 1065 of the gasket 1060 can be described as being disposed between the forward edge 1064 and the closed end (not shown) of the filter bag 1050.

[0197] In the illustrated embodiment, the trailing edge 1065 of the gasket 1060 can be described as being disposed along a plane 1061 that transverses the filter bag axis 1011, which in the illustrated embodiment extends from the filter bag opening of the gasket 1060 to the closed end of the filter bag 1050 as described herein with respect to the other exemplary embodiments.

[0198] The gasket 1060 can be described as having a gasket depth measured along the bag axis 1011 between the forward edge 1064 and a reference plane 1061 oriented transverse to the bag axis 1011. In the illustrated embodiment, the forward edge 1064 of the gasket 1060 has a generally sinusoidal shape, such that the gasket depth varies around the circumference of the gasket 1060. While the illustrated exemplary embodiment includes a generally sinusoidal forward edge 1064, many alternative shapes can be used for the gasket forward edge used in one or more embodiments of the gasket found in the filter bags described herein. Some possible alternative shapes include, but are not limited to, a sawtooth shape, a square wave shape, and the like. A gasket having a varying gasket depth as described herein is typically easier to advance on a receiver surface, such as the receiver 1030, since it does not present a flat edge transverse to the direction in which the gasket 1060 must be advanced when moving the gasket 1060 into the receiver 1030.

[0199] 33 is that the receiver 1030 can include a receiving surface 1039 having a shape corresponding to that of a forward edge 1064 of the gasket 1060. The correspondingly shaped forward edge 1064 and receiving surface 1039 can aid in proper sealing of the gasket 1060 in the receiver 1030 by providing an axial sealing element in the radial seal that is also preferably provided between the gasket and receiver of the systems described herein. In addition to or instead of providing an axial sealing element, the correspondingly shaped forward edge 1064 and receiving surface 1039 can, in one or more embodiments, limit proper mounting of the gasket 1060 and associated filter bag 1050 in the receiver 1030 to only one desired orientation.

[0200] 34-35 illustrate an additional optional feature that may be found in one or more embodiments of the filter bags and filter bag assemblies described herein. Generally, FIGS. 34-35 illustrate a gasket 1160 having varying pocket depths and a support ring 1146 of a service frame having a corresponding shape that matches the varying pocket depths found in the gasket 1160.

[0201] 34-35 includes a tubular body and is attached to a gasket 1160 at a bag opening of the filter bag 1150, as described herein with respect to the other exemplary embodiments of the filter bag. Also as described herein with respect to the other exemplary embodiments of the filter bag, the filter bag 1150 defines a bag axis 1111 that extends through the bag opening and a closed end (not shown) of the filter bag 1150.

[0202] The gasket 1160 includes a sealing member 1166 extending around the periphery of the gasket 1160, as described herein with respect to other exemplary embodiments of the filter bags. Although the illustrated embodiment includes the sealing member 1166 on an outer surface of the gasket 1160, the sealing member 1166 may be disposed on an inner surface of the gasket 1160, as described with respect to some exemplary embodiments of the filter bags described herein.

[0203] The service frame includes a support ring 1146 to which the extension posts 1142, 1144 are attached, as described herein with respect to other exemplary embodiments of service frames used with the filter bags described herein. The support ring 1146 includes a front edge 1147 that faces away from the closed end (not shown) of the filter bag 1150 when the service frame is placed within the filter bag 1150. The support ring 1146 also includes a rear edge 1149 that faces the closed end (not shown) of the filter bag 1150 when the service frame is placed within the filter bag 1150.

[0204] The illustrated exemplary embodiment of the support ring 1146 includes a leading edge 1147 that is not straight, specifically forming the support ring 1146 with a varying width measured along the bag axis 1111 between the leading edge 1147 and a reference plane 1141 that, in the illustrated embodiment, is transverse to the bag axis 1111. In the illustrated embodiment, the reference plane 1141 and a trailing edge 1149 of the support ring 1146 are coincident, although such a configuration is not required.

[0205] 35 (taken at line 35-35 of FIG. 34), the illustrated gasket 1160 includes a pocket 1163. In the illustrated embodiment, the pocket 1163 has a pocket depth measured along the bag axis 1111 between a forward end 1168 and a reference plane 1161 that intersects the bag axis 1111.

[0206] While the pocket depth in many of the exemplary embodiments of the gaskets described herein may be uniform, in the embodiment shown in Figures 34-35, the pocket depth varies around the circumference of the gasket 1160. The varying depth of the pocket 1163 is shown in Figure 35, where the forward end 1168 of the pocket 1163 varies its position relative to the reference plane 1161 between the position in the cross-sectional view of Figure 35 and the bottom of the gasket 1160 where the forward end 1168' of the pocket 1163 is located farther from the reference plane 1161.

[0207] Advantages of a varying pocket depth include, for example, a reduced force required to insert the support ring 1146 into the pocket 1163 compared to, for example, a pocket and corresponding support ring that is uniform in depth / width around the circumference of the gasket 1160. Another potential advantage is an improvement in the sealing engagement between the receiver and the gasket. Yet another advantage is a reduced risk of the gasket being sheared between the gasket and receiver during placement and / or removal of the filter bag.

[0208] 36-37 show an example embodiment of an access panel cover that can be used in one or more embodiments of the air filter system described herein. FIG. 36 shows a portion of an access panel 1214 with a pair of access port covers 1282 configured to close an access port 1280 formed in the access panel 1214. The access port 1280 is used to remove a filter bag 1250 that is located within a contaminated air chamber defined in part by the access panel 1214. As described herein, the filter bag 1250 is removed by pulling the filter bag 1250 along the filter bag axis 1211 through the access port 1280. The illustrated access port cover 1282 is rotatably attached to the access panel 1214 and includes a latch mechanism 1286 configured to capture a latch post 1287 on the access panel 1214 to hold the access port cover 1282 in a closed position over the access port 1280 (as seen with respect to the right access port cover 1282 in FIG. 36).

[0209] In one or more embodiments of the air filter system described herein, the access port cover may include a filter restraining feature configured to limit movement of a closed end of a filter bag of a filter bag assembly described herein and / or movement of a distal end post on a service frame disposed near the closed end. In particular, the filter restraining feature may be configured to limit movement of the closed end and / or the distal end post in a direction transverse to the filter bag axis when the access port is closed by the access port cover as described herein. Limiting movement of the closed end of a filter bag and / or the distal end post of a filter bag assembly described herein in a direction transverse to the filter bag axis may be useful in inhibiting movement of the filter bag assembly during pulse cleaning in use.

[0210] One exemplary embodiment of a filter restraining feature configured to limit movement of the closed end 1256 of the filter bag 1250 is shown in FIG. 36. In particular, the access port cover 1282 includes a filter restraining feature 1284 in the form of a recess configured to receive the closed end 1256 (and any distal end posts disposed therein) when the access port cover 1282 is closing the access port 1280. The recess in the filter restraining feature 1284 acts to limit movement of the closed end 1256 and any distal end posts disposed therein by interference with the sides of the recess 1284.

[0211] While the exemplary embodiment of the access port cover 1282 includes a recess as a filter restraining feature 1284 substantially embossed on the inner surface of the access port cover 1282, Figure 37 illustrates another embodiment in which a flat access port cover 1382 includes a filter restraining feature 1385 attached thereto. The filter restraining feature 1385 defines a recess 1384 configured to receive a closed end of a filter bag and / or a distal end post of a filter bag assembly described herein to limit movement of the closed end of the filter bag and / or the distal end post of the filter bag assembly in a direction transverse to the filter bag axis as described above with respect to Figure 36.

[0212] 38A-38B (FIG. 38A is a front plan view of an access port cover 1482 and FIG. 38B is a side view) show another embodiment in which an access port cover 1482 includes a handle 1488 attached thereto and a filter restraining feature 1484. The filter restraining feature 1484 includes a series of slots 1486 configured to receive the closed end of a filter bag and / or the distal end posts of a filter bag assembly as described herein so as to limit movement of the closed end of the filter bag and / or the distal end posts of the filter bag assembly as described herein in a direction transverse to the filter bag axis.

[0213] 39A-39C (FIG. 39A is a front plan view, FIG. 39B is a top view, and FIG. 39C is a side view of an access port cover 1582) show another embodiment in which the access port cover 1582 includes a handle 1588 attached thereto and a filter restraining feature 1584. The filter restraining feature 1584 is in the form of an elongated V-shaped channel configured to receive a closed end of a filter bag and / or a distal end post of a filter bag assembly as described herein such that the closed end of the filter bag and / or the distal end post of the filter bag assembly as described herein are restricted from moving in a direction transverse to the filter bag axis.

[0214] 40A-40C (FIG. 40A is a front plan view of an access port cover 1682, FIG. 40B is a side view, and FIG. 40C is a cross-sectional view taken at line 40C-40C of FIG. 40A) show another embodiment in which an access port cover 1682 includes a handle 1688 attached thereto and filter restraining features 1684, 1685. The filter restraining feature 1684 is in the form of an elongated U-shaped channel and the upper and lower filter restraining features 1685 are configured to receive the closed end of a filter bag and / or the distal end post of a filter bag assembly as described herein, thereby limiting movement of the closed end of the filter bag and / or the distal end post of a filter bag assembly as described herein in a direction transverse to the filter bag axis.

[0215] 41 illustrates yet another exemplary embodiment of an access port cover 1782 that includes a restraining feature 1785 in the form of a resilient compression member configured to support a closed end of a filter bag and / or a distal end strut of a filter bag assembly as described herein to limit movement of the closed end of the filter bag and / or the distal end strut of a filter bag assembly as described herein in a direction transverse to the filter bag axis. One potential advantage of using a compression member to limit movement of the closed end of the filter bag and / or the distal end strut of the filter bag assembly is that no special alignment is required, i.e., the access port cover 1782 can be positioned to account for mechanical interference between the closed end of the filter bag and / or the distal end strut of the filter bag assembly that may prevent the access port cover 1782 from closing over the access port.

[0216] Numerous structures other than the filter restraining features of the exemplary embodiment shown in Figures 36-41 that are configured to limit movement of the closed end of the filter bag and / or the distal end post of the filter bag assembly can be used in the air filter systems described herein.

[0217] 42-45 show an exemplary embodiment of another feature found in various embodiments of the filter bag assembly and filter system described herein. As described herein, removal and replacement of the filter bag assembly is typically performed from the closed end of the filter bag. That is, the filter bag and service frame with attached filter bag are pulled out of the dirty air chamber of the filter system by grasping the closed end of the filter bag and the service frame. To facilitate manual grasping of the filter bag and service frame, a handle gap may be provided between the service frame and the yoke near the closed end of the tubular body of the filter bag.

[0218] 42-43 show one embodiment of a handle gap between the service frame and the yoke. As shown in FIGURES 42-43, a yoke 1870 includes a lower yoke member 1872 and an upper yoke member 1874. Service frame extension struts 1842, 1844 and distal end strut 1848 can be seen adjacent the gasket assembly 1860 and distal end yoke member 1878, which is furthest from the tubesheet 1820.

[0219] Unlike other embodiments described herein that include a yoke and service frame, a pair of gaps are provided between the service frame and the yoke near the distal ends of the service frame and yoke. In particular, the yoke 1870 includes an angled lower member 1872-1 that extends from a lower yoke member 1872 to a distal yoke member 1878, and an angled upper member 1874-1 that extends from an upper yoke member 1874 to the distal yoke member 1878. The angled member 1872-1 defines a handle gap between the extension strut 1842 and the distal strut 1848, and the angled member 1874-1 defines a handle gap between the extension strut 1844 and the distal strut 1848. These handle gaps allow a user to grasp the service frame and the filter bag thereon to pull the service frame and filter bag away from the tube sheet.

[0220] FIG. 44 shows another exemplary embodiment of a handle gap pair in which the yoke includes a pair of curved portions 1972-1, 1974-1, respectively, connecting the lower yoke member 1972 and the upper yoke member 1974 to the distal yoke member 1978 to provide handle gaps between the lower extension post 1942, the upper extension post 1944, and the distal end post 1948.

[0221] Although the embodiment shown in Figures 42-44 includes a pair of handle gaps, in one or more embodiments, having a single handle gap may be sufficient.

[0222] Figure 45 shows another example embodiment of a handle gap between the yoke and the service frame. In the embodiment shown in Figure 45, the lower extension post 2042 extends beyond the lower yoke member 2072 and the upper extension post 2044 extends beyond the upper yoke member 2074 such that the distal end post 2048 is spaced from the distal yoke member 2078 to provide the handle gap described herein.

[0223] Another method of providing a handle gap between the service frame and the yoke to facilitate removal of the filter bag assembly from the dirty air chamber of the filter systems described herein is to provide a handle attached to the filter bag near the closed end of the tubular body of the filter bag. Examples of filter bag handles are shown in Figures 46-49.

[0224] 46 shows a pair of handles defined by handle openings 2158 formed in the sheet material forming the filter bag 2150. The filter bag 2150 defines a filter bag axis 2111, and the closed end of the tubular body of the filter bag 2150 is defined by a seal 2156 formed between opposed layers of filter sheet material. In one or more embodiments, the seal can be formed by stitching the sheet material at the closed end of the filter bag 2150.

[0225] 47 shows a pair of handles defined by handle openings 2258 formed in the sheet material forming the filter bag 2250. The filter bag 2250 defines a filter bag axis 2211, and the closed end of the tubular body of the filter bag 2250 is defined by a seal 2256 formed between opposed layers of filter sheet material. In one or more embodiments, the seal can be formed by stitching the sheet material at the closed end of the filter bag 2250. One advantage of this embodiment is that by staggering the tabs with the handle openings 2258, waste of filter sheet material can potentially be reduced.

[0226] 48 shows a single handle defined by a handle opening 2358 formed in the sheet material forming the filter bag 2350. The filter bag 2350 defines a filter bag axis 2311, and the closed end of the tubular body of the filter bag 2350 is defined by a seal 2356 formed between opposed layers of filter sheet material. In one or more embodiments, the seal can be formed by stitching the sheet material at the closed end of the filter bag 2350.

[0227] Although openings 2158, 2258, 2358 are illustrated as having an open dimension along the respective bag axis, it will be understood that the openings may simply be in the form of a slit or cut in the flexible sheet material through which a user can insert a hand or removal tool (e.g., a hook, etc.).

[0228] 49 shows another set of handles that may be provided on the filter bags described herein. In particular, both handles 2458-1, 2458-2 may be attached to the filter bag 2450 near the closed end of the bag 2450 defined by the seal 2456 to provide a feature that may be used to pull the filter bag out of the contaminated air chamber. The handle 2458-1 may be attached to the bag 2450 in two locations on one or opposing sides of the filter bag 2450, while the handle 2458-2 may be in the form of a simple loop attached to the opposing side of the filter bag 2450. Of course, many other variations of handle configurations that may be attached to the filter bags described herein are also possible.

[0229] (Embodiment) Described below are one or more non-limiting, alternative, exemplary embodiments of filter bags configured to form a radial seal and air filter systems including filter bags forming a radial seal for the purpose of removing particulate matter from a contaminated air stream (or other gas stream).

[0230] Exemplary embodiment 21 is a filter bag including a tubular body extending from a bag opening to a closed end, the tubular body defined by a flexible filter sheet material defining an interior volume of the filter bag between the bag opening and the closed end, the tubular body defining a filter bag axis extending through the bag opening and the closed end; a gasket assembly attached to the tubular body, the gasket assembly extending around and attached to the bag opening, the gasket assembly including a support ring extending around the bag opening, the support ring having a front edge facing away from the closed end of the tubular body; a gasket attached to the support ring, the gasket extending around the bag opening, the gasket configured to be compressed against the support ring to form a radial seal when the gasket assembly is attached to a dust collector.

[0231] Exemplary embodiment 22 is the filter bag of embodiment 21, wherein the gasket is disposed on the outer surface of the support ring with the gasket facing away from the filter bag axis.

[0232] Exemplary embodiment 23 is the filter bag of embodiment 21, wherein the gasket is disposed on the inner surface of the support ring with the gasket oriented toward the filter bag axis.

[0233] Exemplary embodiment 24 is the filter bag of any one of embodiments 21-23, wherein the flexible filter sheet material defining the interior volume of the filter bag is attached to a gasket of the gasket assembly.

[0234] Exemplary embodiment 25 is the filter bag of embodiment 24, wherein the gasket comprises a gasket flange extending toward the closed end of the tubular body, and the flexible filter sheet material is attached to the gasket flange.

[0235] Exemplary embodiment 26 is a filter bag described in any one of embodiments 21 to 25, wherein the support ring includes a pair of pockets at opposite ends of the support ring, and each pocket of the pair of pockets is configured to receive an extension post of the service frame.

[0236] Exemplary embodiment 27 is a system described in any one of embodiments 21 to 26, wherein the leading edge of the support ring is formed such that the distance between the leading edge of the support ring and the tube sheet varies around the circumference of the support ring.

[0237] Exemplary embodiment 28 is a filter bag according to any one of embodiments 21 to 27, wherein the filter bag comprises a handle attached to the closed end of the tubular body, the closed end being located between the bag opening and the handle in the filter bag axial direction.

[0238] Exemplary embodiment 29 is the filter bag of embodiment 28, wherein the closed end of the tubular body is defined by a seal formed between opposing layers of flexible filter sheet material, optionally the seal comprising a stitch.

[0239] Exemplary embodiment 30 is the filter bag of embodiment 29, wherein the handle comprises a handle opening formed in the flexible filter sheet material.

[0240] Exemplary embodiment 31 is an air filter system including a tube sheet separating a housing into a dirty air chamber and a clean air chamber, the tube sheet having an opening that fluidly connects the dirty air chamber to the clean air chamber, the housing including an access panel across the dirty air chamber from the tube sheet; a filter bag assembly configured to be installed in and removed from the dirty air chamber through an access port in the access panel; and a receiver surrounding the opening, the filter bag assembly including a tubular body extending from a bag opening to a closed end, a gasket assembly attached to the tubular body, and a service frame with a distal end strut, the tubular body including a flexible filter sheet defining an interior volume of the filter bag between the bag opening and the closed end. a gasket assembly extending around the bag opening and attached to the bag opening, the gasket assembly including a support ring extending around the bag opening and a gasket attached to the support ring, the support ring having a front edge facing away from the closed end of the tubular body, the gasket extending around the bag opening, the distal end post attached to the support ring by an extension post extending between the distal end post and the support ring, the gasket of the filter bag assembly engaging the receiver to form a radial seal between a sealing surface at the receiver and the gasket such that air passing through the opening in the tubesheet must pass through the filter bag on its way through the opening to and from the dirty air chamber.

[0241] Exemplary embodiment 32 is the system of embodiment 31, wherein the gasket is compressed between the support ring and the sealing surface of the receiver.

[0242] Exemplary embodiment 33 is a system described in embodiment 31 or 32, wherein the front edge of the support ring and the gasket are positioned within the receiver such that a radial seal is formed inside the receiver and the outer surface of the support ring.

[0243] Exemplary embodiment 34 is the system of embodiment 33, wherein the gasket comprises a sealing member, the sealing member being deformed by the leading edge of the support ring and the receiver when the gasket is disposed within the receiver.

[0244] Exemplary embodiment 35 is a system described in any one of embodiments 31-34, wherein the gasket has a forward edge distal from the closed end of the filter bag along the filter bag axis, and the receiver is disposed within the gasket such that a radial seal is formed within the gasket and outside of the receiver at a location between the forward edge of the gasket and the closed end of the filter bag, and optionally the receiver is disposed within the gasket such that a radial seal is formed within the gasket on an outer surface of the receiver facing the gasket.

[0245] Exemplary embodiment 36 is the system described in embodiment 35, wherein the gasket includes a sealing member, the sealing member being deformed by the receiver when the receiver is positioned within the gasket, and a radial seal is formed on an outer surface of the receiver facing the pocket gasket within the gasket.

[0246] Exemplary embodiment 37 is a system described in any one of embodiments 31 to 36, wherein the system includes a yoke attached to the tube sheet, the yoke extending from the dirty air chamber side of the tube sheet into the dirty air chamber, the joint between the yoke and the tube sheet being located between the opening and the sealing surface of the receiver, and when the filter bag assembly is installed in the dirty air chamber, the yoke and service frame are positioned within the interior volume of the filter bag.

[0247] Exemplary embodiment 38 is the system described in embodiment 37, wherein the yoke includes a support channel extending along an edge of the yoke in a direction away from the tube sheet, and the extension support of the service frame is at least partially received within the support channel.

[0248] Exemplary embodiment 39 is a system described in embodiment 37 or 38, wherein the service frame and yoke define a handle gap between the service frame and yoke near the closed end of the tubular body, the handle gap being located between the closed end of the tubular body and the yoke, and the handle gap being configured such that the service frame and filter bag can be easily grasped by hand to remove the filter bag assembly from the contaminated air chamber.

[0249] Exemplary embodiment 40 is a system described in any one of embodiments 31 to 39, wherein the filter bag includes a handle attached to the closed end of the tubular body, the closed end being located between the bag opening and the handle in the filter bag axial direction.

[0250] Exemplary embodiment 41 is a system described in embodiment 40, wherein the closed end of the tubular body is defined by a seal formed between opposing layers of flexible filter sheet material, optionally the seal comprising a suture.

[0251] Exemplary embodiment 42 is the system of embodiment 40 or 41, wherein the handle comprises a handle opening formed in the flexible filter sheet material.

[0252] Exemplary embodiment 43 is a system described in any one of embodiments 31 to 42, wherein the service frame comprises a filter bag assembly length measured along the filter bag axis between the front edge of the support ring and the distal end post that is large enough to prevent the gasket from disengaging from the sealing surface of the receiver when the access port is closed.

[0253] Exemplary embodiment 44 is a system described in any one of embodiments 31 to 43, wherein a service frame is disposed within the interior volume of the filter bag, and optionally the extension strut comprises a first extension strut, and the service frame comprises a second extension strut extending between the distal end strut and the support ring, and the support ring, the first extension strut, the second extension strut, and the distal end strut define a generally rectangular shape of the service frame.

[0254] Exemplary embodiment 45 is a system described in any one of embodiments 31 to 44, wherein the leading edge of the support ring is formed such that the distance between the leading edge of the support ring and the tube sheet varies around the circumference of the support ring.

[0255] Exemplary embodiment 46 is a system according to any one of embodiments 31 to 45, wherein the system includes an access port cover configured to close the access port when the filter bag assembly is installed in the dirty air chamber and a pocket gasket of the filter bag engages the receiver to form a radial seal between the sealing surface of the receiver and the pocket gasket, a chamber crossing distance across the dirty air chamber from the access port cover to the receiver configured to prevent disengagement of the pocket gasket from the sealing surface of the receiver when the access port is closed by the access port cover, and optionally the access port cover configured to limit movement of the distal end post in a direction transverse to the filter bag axis when the access port is closed by the access port cover.

[0256] Exemplary embodiment 47 includes a filter bag assembly, the opening in the tube sheet including a first opening of a plurality of openings, each opening of the plurality of openings fluidly connecting the dirty air chamber to the clean air chamber, the filter bag assembly including a first filter bag assembly of the plurality of filter bag assemblies, each filter bag assembly of the plurality of filter bag assemblies configured to be installed in and removed from the dirty air chamber through an access port in the access panel, the receiver including a first receiver of the plurality of receivers, each receiver extending into the dirty air chamber around one of the plurality of openings, a gasket of the first filter bag assembly engaging the first receiver to form a radial seal between a sealing surface at the first receiver and the gasket such that air passing through the first opening must pass through the filter bag of the first filter bag assembly as it passes through the first opening into or out of the dirty air chamber, and a second opening of the plurality of openings disposed within a second receiver of the plurality of receivers, a gasket of the second filter bag assembly of the plurality of filter bag assemblies being configured to be disposed within the second receiver of the plurality of receivers. 47. The system of any one of embodiments 31-46, wherein a filter bag axis that engages the second receiver and extends through the bag opening and closed end of the filter bag of the first filter bag assembly is a first filter bag axis that extends through a center of the bag opening and a center of the closed end of the filter bag of the first filter bag assembly, the filter bag of the second filter bag assembly defines a second filter bag axis that extends through a center of the bag opening and a center of the closed end of the filter bag of the second filter bag assembly, the filter bag of the first filter bag assembly has a width measured in a width direction that is transverse to both the first filter bag axis and the second filter bag axis, the first filter bag assembly and the second filter bag assembly are adjacent to each other in the width direction, and a distance along the width direction between the first filter bag axis and the second filter bag axis is three times or more the width of the first filter bag, and optionally each filter bag assembly of the plurality of filter bag assemblies extends across the contaminated air chamber from the receiver to the access panel.

[0257] Example embodiment 48 is the system described in embodiment 47, wherein the plurality of filter bag assemblies includes three or more filter bag assemblies, and an inter-assembly distance between each pair of adjacent filter bag assemblies of the plurality of filter bag assemblies is the same as or greater than the distance between the first filter bag axis and the second filter bag axis.

[0258] Exemplary embodiment 49 is the system of any one of embodiments 31-48, wherein the filter bag of each filter bag assembly of the plurality of filter bag assemblies comprises an envelope-type filter bag.

[0259] The disclosures of all patents, patent documents, and publications identified herein are incorporated by reference in their entirety into this application as if each was individually incorporated into this application. In the event of a conflict or inconsistency between this document and the disclosure of any such incorporated document, this document will control.

[0260] An air filter system, a filter bag assembly, a filter bag with a gasket, and methods of using and assembling the same have been described herein, and several possible variations have been described. It is understood that these and other variations and modifications of the present invention will be apparent to those skilled in the art without departing from the spirit of the invention, and that the present invention is not limited to the exemplary embodiments described herein. Accordingly, the present invention is limited only by the claims provided below and their equivalents. It is also understood that the present invention may be suitably practiced in the absence of any element not identified as essential in the disclosure herein.

Claims

1. 1. An air filtration system comprising: a tube sheet separating the housing into a dirty air chamber and a clean air chamber, the tube sheet having an opening for fluidly connecting the dirty air chamber with the clean air chamber, the housing having an access panel directly across the dirty air chamber from the tube sheet; a filter bag assembly configured to be installed in and removed from the contaminated air chamber through an access port in the access panel; a receiving portion surrounding the opening; the filter bag assembly comprising: a service frame including a support ring and a distal end post attached to the support ring by an extension post extending between the distal end post and the support ring, the support ring having a front edge facing away from the distal end post; a filter bag, the filter bag comprising a flexible filter sheet material and having a bag opening and a closed end defining an interior volume of the filter bag, the filter bag defining a filter bag axis extending through the bag opening and the closed end; a pocket gasket extending around the bag opening, the pocket gasket having a pocket, the front edge of the support ring being positioned within the pocket and adjacent the tube sheet when the filter bag assembly is installed in the contaminated air chamber, and the extension strut extending away from the tube sheet toward the access panel; the pocket gasket of the filter bag assembly engages the receiver to form a radial seal between a sealing surface at the receiver and the pocket gasket such that air passing through the opening in the tube sheet must pass through the filter bag on its way to or from the contaminated air chamber through the opening.

2. The system of claim 1 , wherein the pocket gasket is compressed between the support ring and the sealing surface of the receiver.

3. 3. The system of claim 1, wherein the front edge of the support ring and the pocket of the pocket gasket are positioned within the receiver such that the radial seal is formed inside the receiver and an outer surface of the support ring, and optionally the pocket gasket includes a sealing member that is deformed by the receiver when the front edge of the support ring and the pocket of the pocket gasket are positioned within the receiver.

4. 3. The system of claim 1, wherein the pocket gasket has a forward edge distal to the closed end of the filter bag along the axis of the filter bag, the receiver is disposed within the pocket gasket such that the radial seal is formed within the pocket gasket and outside of the receiver at a location between the forward edge of the pocket gasket and the closed end of the filter bag, optionally the receiver is disposed within the pocket gasket such that the radial seal is formed within the pocket gasket on an outer surface of the receiver facing the pocket gasket, and optionally the pocket gasket comprises a sealing member that is deformed by the receiver when the receiver is positioned within the pocket gasket, and the radial seal is formed within the pocket gasket on the outer surface of the receiver facing the pocket gasket.

5. 3. The system of claim 1 or 2, wherein the service frame comprises a filter bag assembly length, measured along the axis of the filter bag between the front edge of the support ring and the distal end post, that is large enough to prevent the pocket gasket from disengaging from the sealing surface of the receiver when the access port is closed.

6. 3. The system of claim 1, wherein the support ring, the distal end struts, and the extension struts of the service frame are disposed within the interior volume of the filter bag, and optionally the extension struts comprise first extension struts and the service frame comprises second extension struts extending between the distal end struts and the support ring, and the support ring, the first extension struts, the second extension struts, and the distal end struts define a generally rectangular shape for the service frame.

7. 3. The system of claim 1, wherein the system comprises a yoke attached to the tube sheet, the yoke extending from a dirty air chamber side of the tube sheet into the dirty air chamber, a joint between the yoke and the tube sheet being located between the opening and the sealing surface of the receiver, the yoke and the service frame being positioned within the interior volume of the filter bag when the filter bag assembly is installed in the dirty air chamber, and optionally the yoke comprising a support channel extending along an edge of the yoke in a direction away from the tube sheet, the extension support of the service frame being at least partially received within the support channel.

8. 8. The system of claim 7, wherein the service frame and the yoke define a handle gap between the service frame and the yoke near the closed end of the tubular body, the handle gap being located between the closed end of the tubular body and the yoke, and the handle gap is configured to facilitate manual grasping of the service frame and the filter bag to remove the filter bag assembly from the contaminated air chamber.

9. 3. The system of claim 1, wherein the leading edge of the support ring is shaped such that the distance between the leading edge of the support ring and the tube sheet changes as the leading edge moves around the circumference of the support ring.

10. 3. The system of claim 1, wherein the front edge of the support ring comprises a plurality of retention tabs extending away from the closed end of the filter bag, and the pocket gasket comprises a plurality of tab openings configured to receive the retention tabs, and optionally the tab openings extend from the pocket through a front edge of the pocket gasket and through the gasket, whereby the plurality of retention tabs are exposed at the front edge of the pocket gasket.

11. 3. The system of claim 1 or 2, wherein the filter bag comprises a handle attached to the closed end of the filter bag, wherein the closed end is located between the bag opening and the handle when moved along the axial direction of the filter bag, and / or the filter bag comprises an envelope-type filter bag.

12. 3. The system according to claim 1, wherein the filter bag of each filter bag assembly of the plurality of filter bag assemblies includes a handle attached to the closed end of the tubular body, and the closed end is positioned between the bag opening and the handle when moved along the axial direction of the filter bag.

13. A filter bag comprising: a tubular body extending from a bag opening to a closed end, the tubular body being defined by a flexible filter sheet material that defines an interior volume of the filter bag between the bag opening and the closed end, the tubular body defining an axis of the filter bag extending through the bag opening and the closed end; a gasket attached to the tubular body, the gasket extending around and attached to the periphery of the bag opening; The gasket comprises: an outer surface extending around the periphery of the gasket facing away from the axis of the filter bag; an inner surface of the gasket extending around the periphery and facing the axis of the filter bag; a forward edge of the tubular body located distally from the closed end; and a rearward edge of the tubular body located between the forward edge and the closed end. a pocket formed in the gasket between the outer surface and the inner surface; the pocket having a pocket opening and a forward end located between the pocket opening and the forward edge of the gasket, the pocket configured to receive a support ring extending around the periphery of the bag opening.

14. The filter bag of claim 13 , wherein the pocket opening opens into the interior volume of the filter bag.

15. 15. The filter bag of claim 13 or 14, wherein the pocket opening faces the closed end of the tubular body.

16. 15. The filter bag of claim 13 or 14, wherein the pocket has a pocket depth measured along the axis of the bag between the forward end of the pocket and a reference plane oriented transversely to the axis of the bag, the pocket depth varying when moving around the circumference of the gasket.

17. 15. The filter bag of claim 13 or 14, wherein the gasket has a gasket depth measured along the axis of the bag between the forward edge and a reference plane oriented transversely to the axis of the bag, the gasket depth varying when moving around the circumference of the gasket.

18. 15. The filter bag of claim 13 or 14, wherein the gasket has a gasket-pocket depth measured along the axis of the bag between the forward end of the pocket and a reference plane, the gasket-pocket depth varying when moving around the circumference of the gasket.

19. 15. The filter bag of claim 13 or 14, wherein the filter bag comprises a handle attached to the closed end of the tubular body, the closed end being located between the bag opening and the handle when moved along an axial direction of the filter bag, optionally the closed end of the tubular body being defined by a seal formed between opposing layers of the flexible filter sheet material, optionally the seal comprising a stitch, and optionally the handle comprising a handle opening formed in the flexible filter sheet material.

20. 15. The filter bag of claim 13 or 14, wherein the gasket includes a plurality of tab openings extending through the gasket from the forward end of the pocket through the forward edge of the gasket.

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