Safety manway for internal vessel screen

Abstract

A hold down screen assembly including a removable manway and related methods of accessing a vessel interior are disclosed. The hold down screen assembly can include a plurality of screen panels that are insertable through a vessel manway opening and can be coupled together to reside across a cross-section of a fluid processing vessel. At least one of the screen panels can define a screen opening that operably receives a removable manway. The removable manway can be selectively locked or unlocked to the screen opening using a locking tool. The removable manway can be selectively removed or installed through the vessel manway opening using a locking tool and one or more lifting tools. The removable manway can be selectively installed or removed from the screen opening without maintenance personnel having to enter the vessel interior.

Description

[0001] SAFETY MANWAY FOR INTERNAL VESSEL SCREEN

[0002] RELATED APPLICATIONS

[0003] The present application claims priority to United States Provisional Application No. 63 / 670,506 filed July 12, 2024, the entire content of which is hereby incorporated by reference in its entirety.

[0004] TECHNICAL FIELD

[0005] The present disclosure relates to media hold down screens for fluid processing vessels. More specifically, the present disclosure is directed to a removable manway that allows maintenance personal to access a media bed with an interior of the fluid processing vessel from outside the fluid processing vessel when the manway is removed.

[0006] BACKGROUND

[0007] In some petrochemical and general industry applications, fluid processing vessels are used to filter and process fluid streams. The fluid streams can be filtered and processed by directing the fluid through one or more layers of treatment media. In some applications, for instance, certain gas processing applications, the treatment media can comprise a catalytic resin media that is used to facilitate reactions and the production of desirable chemicals. This catalytic resin media can be expensive to purchase and replace, making it desirable to minimize the amount of media carried ou t of the fluid processing vessel with the fluid stream.

[0008] Fluid processing vessels can include internal hold down screens that are positioned above or below the treatment media such that the hold down screen is downstream of the treatment media. The hold down screens can comprise slots or pores that are smaller than the treatment media particles such that the fluid stream can pass through the hold down screen, but the treatment media cannot. This prevents loss of the treatment media during normal processing conditions and / or backwash'regeneration cycles.

[0009] In some instances , maintenance personnel may need to inspect an interior of the vessel, for example, the vessel wail, any vessel internals or a media bed. With conventional media hold down screens maintenance personnel must physically enter the fluid processing vessel to disassemble the media hold down screen. The enclosed and confined space within the vessel can be low in oxygen or contain harmful vapors, along with other potential hazards, such that time consuming and expensive safety measures must be instituted to ensure the safety of the maintenance personnel. As such, it would be advantageous to improve upon conventional media hold down screen design to enhance safety for maintenance personnel.

[0010] SUMMARY

[0011] The present disclosure addresses the aforementioned safety concerns by providing a media hold down screen assembly that comprises a removable manway panel. The removable manway panel can be removed from the media hold down screen assembly from outside a fluid processing vessel by accessing the removable manway panel through a vessel manway. The removable manway panel can be positioned in a screen manway opening defined in the media hold down screen assembly, whereby the removable manway panel is selectively locked or unlocked to the media hold down screen assembly. The removable manway panel can comprise a rotatable locking bar that can be rotated to engage one or more slots in the screen manway opening to couple the removable manway panel to the media hold down screen assembly. The rotatable locking bar can further comprise one or more locking members to prevent rotation of the locking bar when the locking bar is in a locked position relative to the media hold down screen assembly. The locking bar can include an engagement pin and one or more engagement channels that project upward from the locking bar such that a locking tool can selectively engage and rotate the locking bar between the locked and unlocked positions. The removable manway panel can include one or more lifting lugs such that when the locking bar is in the unlocked position, a lifting tool can engage the lifting lugs and lift the removable manway panel from the screen manway opening and remove the removable manway panel out the vessel manway. Through the use of the of the removable manway panel, the locking tool and the lifting tool, an operator can selectively remove the removable manway panel to access the treatment media and vessel interior without physically entering fluid processing vessel.

[0012] In some implementations, a plurality of screen panels are configured to attach to each other such that a hold down screen assembly is defined. The hold down screen assembly can be configured to fit within a processing vessel and to have a similar geometry and size as a cross section of the processing vessel. Further, the hold down screen assembly can define a screen manway opening. A removable manway panel can be configured to fit within the screen manway opening and to be removably attached to the hold down screen assembly. A locking tool bar tool can be used to selectively lock and unlock the removable manway panel to the hold down screen assembly. Further, a removal tool can be used by a maintenance personnel to remove the removable manway panel from the hold down screen assembly 'without the operator entering the processing vessel.

[0013] BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1A is a perspective view’ of a hold down screen assembly with a removable manway in a locked position according to an embodiment of the present invention.

[0015] FIG. 1 B is a side view of the hold down screen assembly of FIG. 1A.

[0016] FIG. 1C is a side view of the hold down screen assembly of FIG. 1A offset 90° from the view of FIG. IB.

[0017] FIG. 1 D is a top view’ of the hold down screen assembly of FIG. 1 A. FIG. 1E is a section view of the hold dowm screen assembly of FIG. 1 A taken at section

[0018] A-Aof FIG. 1D.

[0019] FIG. 1F is a perspective view of the hold down screen assembly of FIG. 1A with the removable manway in an unlocked position.

[0020] FIG. 1G is a perspective view of the hold down screen assembly of FIG. 1A with the removable manway separated from a screen opening.

[0021] FIG. 2A is a top view of a hold down screen assembly of FIG. 1 A absent the removable manway..

[0022] FIG. 2B is a section view of the hold down screen assembly of FIG. 2A taken at section B-B of FIG. 2A.

[0023] FIG. 2C is detail section view of the hold down screen assembly of FIG. 2A taken at Detail C of FIG. 2B.

[0024] FIG. 3A is a top perspective view of a removable manway according to an embodiment of the present invention.

[0025] FIG. 3B is a top view of the removable manway of FIG. 3 A.

[0026] FIG. 3C is a section view of the removable manway of FIG. 3A taken at section D-D of FIG. 3B.

[0027] FIG. 4 is a side view of a locking tool for use with the hold down screen assembly of FIG. 1A.

[0028] FIG. 5 A is a top perspective view' of the locking tool of FIG. 4 engaged with the hold dowm screen assembly of FIG. 1A.

[0029] FIG. 5B is a detail view' of the locking tool engaged with the hold dowm screen assembly taken at Detail E of FIG. 5 A.

[0030] FIG. 6A is a perspective view' of a lifting tool for use with the hold dowm screen assembly of FIG. 1A. FIG. 6B is a section view of a pair of lifting tools lifting a removable manway from the hold down screen assembly of FIG. 1A.

[0031] While various embodiments are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the claimed inventions to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter.

[0032] DETAILED DESCRIPTION OF THE DRAWINGS

[0033] Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the foil owing description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

[0034] The following discussion is presented to enable a person skilled in the art to make and use embodiments of the disclosure. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the disclosure. Thus, embodiments of the disclosure are not intended to be limited to embodiments shown but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the disclosure. Skilled artisans will recognize the examples provided herein have many useful alternatives and fail within the scope of embodiments of the disclosure.

[0035] Embodiments disclosed herein include media hold down screens having a removable manway panel that can be used within fluid processing tanks or vessels in conjunction with media beds through w'hich gases and liquids are directed. Such media beds can be used in a variety of processes, including but not limited to catalytic, molecular sieves, alumina drying, resin ion exchange, carbon filtering, etc. Various fluids, including but not limited to liquid, gas, oil, w'ater, etc., can be processed through the vessel. Flow' through the reassembly in either an up flow or down flow' condition can be compressible (gas) or incompressible (liquid). The hold dowm screen assembly and removable manway panel described herein have are configured to prevent the processing media from passing through, w'hile allowing the processed fluid to pass.

[0036] As illustrated in FIGS. 1A - 1G, a hold down screen assembly 100 can comprise a plurality of screen sections 102a, 102b, 102c. The screen sections 102a, 102b, 102c generally define a screen surface 104 having defined slots or apertures of a desired size that are selected to be smaller than a treatment media within a processing vessel. For instance, in the case of the treatment media comprising a catalytic media, the slot or apertures are smaller than a diameter of individual media beads such that the catalytic media cannot pass through the screen surface 104. In a representative embodiment, the screen surface 104 can comprise slots formed by welding lengths of shaped wire 106 to support ribs 108, such that the slots are defined between adjacent and parallel lengths of shaped wire 106. Alternatively, the screen surface 104 can comprise perforated sheets or expanded metal. During initial assembly of the hold down screen assembly 100, the individual screen sections 102a, 102b, 102c can be individually inserted through a vessel manway and assembled inside the processing vessel.

[0037] As best seen in FIGS. 1G and 2A-2C, a screen opening 106 is defined within one of the screen sections 102a, I02b, 102c, and most preferably within a central screen section, i.e., screen section 102b. Generally, the screen opening 106 defines an opening perimeter 108 defined by opening walls 110a, 110b, 110c and 110d. As illustrated, opening perimeter 108 has a square shape though other geometric shapes, including for example, rectangles, triangles, ovals and other shapes could be utilized. Preferably, at least one of the opening walls 110a, 110b, 110c, 110d defines a wall slot 112. As seen in FIG. 1F, opposed walls, for example, opening walls 110a and 110c can each include wall slot 112. Alternatively, each of the opening walls 110a, 110b, 110c, 110d can include wall slot 112. A sealing channel 114 is located in proximity to the opening perimeter 108 and can be located below opening walls 110a, 110b, 110c, 110d and screen surface 104 as shown in FIGS. 2B and 2C or alternatively, adjacent to the opening walls 110a, 110b, 110C, 110d. Generally, the sealing channel 114 extends inwardly from the opening perimeter 108 such that a distance between opposed sides of the sealing channel 114 is less than a distance between opposed opening walls, i.e„ a distance between opening walls 110a and 110c or a distance between opening walls 110b and 110d. A sealing member 116 can be positioned within the sealing channel 114, for example, a sealing rope 118. In some embodiments, the sealing rope 118 can comprise a fiberglass material, however other materials can be used that are pliable enough to fit within the sealing channel 114. In an exemplary embodiment, the sealing rope 118 is sized such that it fills the entire sealing channel 114 when compressed.

[0038] Referring to FIGS. 3A-3C, hold down screen assembly 100 can further comprise a removable manway 120. Generally, the removable manway 120 comprises a manway perimeter 122 defined by manway walls 124a, 124b, 124c and 124d. Generally, the manway perimeter 122 will have the same geometric shape, but be slightly undersized, as the opening perimeter 108 such that the removable manway 120 can be positioned to fit within the screen opening 106 and reside on the sealing channel 114. The removable manway 120 further comprises a screen surface 126 constructed to match the screen surface 104, for example, having slots defined by shaped wire 106 and support ribs 108. Removable manway 120 can include an upwardly facing engagement pin 127 that is preferably centrally located within the manway perimeter 122. At least one of the manway walls 124a, 124b, 124c, 124d includes an upwardly projecting lifting lug 128. As best seen in FIG. 3 A, opposed manway walls such as manway walls 124b and 124d can each include lifting lug 128 having a lug opening 129.

[0039] As seen in FIGS. 3A-3C, the removable man way 120 can further comprise a rotatable locking bar 130. The rotatable locking bar 130 can comprise a generally flat body 132 defined between a first end 134a and a second end 134b. The rotatable locking bar 130 includes a centrally located mounting aperture (not depicted) that is sized to receive and mount over the engagement pin 127. A fastener 138 can rotatably couple the rotatable locking bar 130 onto the engagement pin 127. A pair of engagement channels 140a, 140b are located on opposed sides of the engagement pin 127 and project upwardly from the flat body 132. The rotatable locking bar 130 further comprises at least one locking member 142, for example, a rotatable hook member 144 at either or both of the first end 134a, 134b. The rotatable hook member 144 can include a hook portion 146 and a coupling portion 148. In an alternative embodiment, the rotatable locking bar 130 can comprise two flat bodies 132 arranged in a shape, such that there are four individual ends.

[0040] Generally, the removable manway 120 is selectively attached to or removed from the screen opening 106. For example, during normal operation, the removable manway 120 is positioned within the screen opening 106 and the rotatable locking bar 130 is arranged in a locked position 150 as shown in FIGS 1 A and ID, that maintains the position of the removable manway 120 relative to the screen opening 106 and ensures that a seal is maintained between the screen opening 106 and the removable manway 120 to prevent passage of the treatment media. As the manway perimeter 122 is slightly undersized with respect to the opening perimeter 108, the removable manway 120 fits within the opening walls 110a, 110b, 110c, 110d and the manway walls 124a, 124b, 124c, 124d reside on the sealing channel 114. The rotatable locking bar 130 is rotated such that the first end 134a and second end 134b rotate into the wall slot 112 on opening wall 110a and 110c respectively. In the embodiment in which the rotatable locking bar 130 is in a shape having four ends, the four ends can be rotated such that each end rotates into wail slots 112 on each opening wall 110a, 110b, 110c, llOd. The rotatable hook member 144 can be rotated over such that the coupling portion 148 rotates over and engages the opening wall 110a, thus preventing unintentional rotation and disengagement of the rotatable locking bar 130 from the slots 112. With the rotatable locking bar 130 in the locked position 150, the sealing member 116 is compressed by the manway walls 124a, 124b, 124c, 124d, thereby preventing passage of the treatment media between the removable manway 120 and the screen opening 106.

[0041] During inspection and maintenance, the rotatable locking bar 130 is arranged in an unlocked position 152 as shown in FIG. IF, whereby the removable manway 120 can be selectively removed from or positioned in the screen opening 106. In the unlocked position 152, the rotatable locking bar 130 is rotated such that the first end 134a and second end 134 are contained within and do not project outside the manway perimeter 122 and the locking member 142 is rotated so as to be open and not engaging the opening wall 110a. With the rotatable locking bar 130 positioned such that the first end 134a and second end 134 are not located within and engaging the wall slots 112, there is no positive connection between the removable manway 120 and the screen opening 106. Instead, the removable manway 120 is merely sitting on the sealing channel 114.

[0042] During inspection and / or maintenance of the fluid processing vessel, maintenance personnel can remove a vessel manway. Using a locking tool 200 as shown in FIGS. 4, 5 A and 5B, the maintenance personnel can manipulate the rotatable locking bar 130 from the locked position 150 to the unlocked position 152. Generally, the locking tool 200 comprises a shaft 202 having a first end 204 and a second end 206. In some embodiments the shaft 202 is formed of tubing or pipe such that shaft 202 has a hollow interior 207 defined between the first end 204 and second end 206 to reduce the overall weight of the locking tool 200. The shaft 202 is selected to have a desired length sufficient that the maintenance personnel can access the removable manway 120 with the locking tool 200 from outside the fluid processing vessel. The first end 204 can include a handle 208 for manipulation by the maintenance personnel. The second end 206 can include an engagement opening 210 and engagement arms 212a, 212b that are on opposed sides of the hollow shaft 202 and extend outwardly from the hollow shaft 202.

[0043] To manipulate the rotatable locking bar 130 from the locked position 150 to the unlocked position 152, the maintenance personnel lower the second end 206 into the fluid processing vessel. Either of the engagement anus 212a, 212b can be directed into the hook portion 146 such that the hook portion 146 can be lifted, thereby rotating the rotatable hook member 144 such that the coupling portion 148 is no longer in contact with the opening wall 110a. Next, the engagement opening 210 drops over the engagement pin 127 with the engagement arms 212a, 212b positioned within the engagement channels 140a, 140b respectively as shown in FIG. 5B. Placement of the engagement opening 210 over the engagement pin 127 provides support and alignment to the locking tool 210 such that the shaft 202 can only rotate around an upwardly facing axis defined by the engagement pin 127. The maintenance personnel can then rotate the locking tool 200 using the handle 208 located external to the fluid processing vessel, which causes the engagement arms 212a, 212b to abut and engage the engagement channels 140a, 140b, whereby the rotatable locking bar 130 is caused to spin about the engagement pin 127. As the rotatable locking bar 130 is rotated toward the unlocked position 152, the first end 134a and the second end 134b are rotated out of their corresponding slot 112. With the rotatable hook member 144 disengaged from the opening wall 110a and the rotatable locking bar 130 oriented such that the first end 134a and second end 134 are outside the slots 112, the rotatable locking bar 130 is in the unlocked position 152 and prepared for removal from the screen opening 106.

[0044] With the rotatable locking bar 130 in the unlocked position 152, maintenance personnel can utilize a lifting tool 300 to lift the removable manway panel 120 from the screen opening 106. As shown in FIGS. 6A and 6B, a lifting tool 300 generally comprises a shaft 302 having a first end 304 and a second end 306. In some embodiments, the shaft 302 is formed of tubing or pipe such that shaft 302 has a hollow interior 307 between the first end 304 and second end 306 to reduce the overall weight of the lifting tool 300. The shaft 302 is selected to have a desired length sufficient that the maintenance personnel can access the removable manway 120 with the lifting tool 300 from outside the fluid processing vessel. The first end 304 can comprise a handle 308 and a bracket 310 having a bracket opening 312. A tether or other securing line can be fastened to the bracket opening 312 to allow for recovery of the lifting tool 300 if dropped into the fluid processing vessel. The second end 302 can include a lifting hook 314. As shown in FIG. 6B, the maintenance personnel can manipulate the lifting tool 300 such that the lifting hook 314 captures the lug opening 129 of the lifting lug 128. In instances where the removable manway 120 comprises multiple lifting lugs 130, the maintenance personnel can simultaneously employ multiple lifting tools 300, potentially providing for better control and positioning of the removable manway panel 130, to lift the removable manway panel 120 from the screen opening 106. Depending upon the work being done, the maintenance personnel can completely lift and remove the removable manway panel 120 from the vessel manway or alternatively, they can set the removable manway panel 120 on screen section 102a or screen section 102c.

[0045] Upon completion of any inspection or maintenance, the maintenance personnel can use one or more lifting tools 300 to reposition the removable manway panel 300 relative to the screen opening 106. After verifying the rotatable locking bar 130 is in the unlocked position 152, the maintenance personnel can capture the lug openings 129 with the lifting hook 304. Using the lifting tool 300, the removable manway panel 300 is then lowered into the screen opening 106 such that that the removable manway panel 300 resides on the sealing channel 114.

[0046] Finally, the maintenance personnel completes the reinstallation of the removable manway panel 120by directing the rotatable locking bar 130 into the locked position 150. The engagement opening 210 on the locking tool 200 is directed over the engagement pin 127 with the engagement amis 212a, 212b positioned in the engagement channels 140a, 140b. Using the handle 208, the maintenance personnel can then rotate the locking tool 200 thereby causing the engagement arms 212a, 212b to abut and engage the engagement channels 140a, 140b, whereby the rotatable locking bar 130 is caused to spin about the engagement pin 127. As the rotatable locking bar 130 is rotated toward the locked position 150, the first end 134a and the second end 134b are rotated into their corresponding slot 112. With the first end 134a and second end 134 in their corresponding slot, either of the engagement arms 212a, 212b can be directed to lift the hook portion 146, thereby rotating the rotatable hook member 144 such that the coupling portion 148 drops over and into contact with the opening wall 110a. With the rotatable locking bar 130 in the locked position such that the removable manway panel 120 is operably coupled in the screen opening 106, the sealing member 116 is compressed by the manway walls 124a, 124b, 124c, 124d, thereby preventing passage of the treatment media between the removable manway 120 and the screen opening 106 and processing within the fluid processing vessel can be restarted.

[0047] It will be appreciated by those skilled in the art that while the disclosure has been described above in connection with particular embodiments and examples, the disclosure is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein. Various features and advantages of the disclosure are set forth in the following claims.

Claims

Claims:

1. A hold down screen assembly for use in a media vessel, comprising: a hold down screen defining a screen opening, the hold down screen including a sealing channel surrounding the screen opening, the hold down screen further including at least one slot in proximity to the screen manway opening; a removable manway configured for insertion in the screen opening such that the removable manway resides on the sealing channel; and a locking bar rotatably attached to the removable manway, the locking bar rotatable between a locked position wherein the locking bar engages the at least one slot and an unlocked position wherein the manway panel is selectively removable from the screen manway opening.

2. The hold down screen assembly of claim 1 , wherein a sealing member is insertable into the sealing channel.

3. The hold down screen assembly of claim 2, wherein the sealing channel is positioned below the screen manway opening and the sealing member is compressed by the manway panel.

4. The hold down screen assembly of claim 1, wherein the locking bar comprises an upwardly facing engagement pin and a pair of upper projecting engagement channels, and wherein the hold down screen assembly further comprises:a locking tool having a hollow shaft defined between a first end and a second end, wherein the first end includes a handle and wherein the second end includes an engagement opening and a pair of engagement arms such that the engagement opening is positionable over the upwardly facing engagement pin, and wherein rotation of the handle directs the engagement arms into engagement with the upper projecting engagement channels such that the locking bar is selectively rotated between the locked position and the unlocked position.

5. The hold down screen assembly of claim 5, wherein the locking bar comprises at least one locking hook, the at least one locking hook engaging the hold down screen when in the locked position.

6. The hold down screen assembly of claim 1, wherein the manway panel comprises at least one lifting lug having a lug opening, and wherein the hold down screen assembly further comprises: a lifting tool having a lift tool first end and a lift tool second end, wherein the lift tool second end includes a lift hook, and wherein the lift hood can engage the lug opening to lift the removable manway from the screen opening when the locking bar is in the unlocked position.

7. The hold down screen assembly of claim 1, wherein the hold down screen comprises a plurality of screen panels, 'wherein the screen opening is defined in a center screen panel.

8. A fluid processing vessel comprising: the hold down screen assembly of claim 1 .

9. A method for maintaining a hold down screen assembly in a fluid processing vessel, comprising: inserting a tool through a vessel manway of the fluid processing vessel to access an interior of the fluid processing vessel; and engaging a removable manway with the tool to selectively install or remove the removable manway from a screen opening defined in a media hold down screen.

10. The method of claim 9, wherein the tool comprises a locking tool for engaging a locking bar rotatably coupled to the removable manway.

11. The method of claim 10, further comprising: rotating the locking tool so as to rotate the locking bar such that the locking bar engages at least one slot defined proximate the screen opening to define a locked position.

12. The method of claim 11, further comprising: engaging at least one locking hook on the locking bar with the hold down screen to restrain the locking bar from rotating when in the locked position.

13. The method of claim 9, where the tool comprises a lifting tool for engaging a lifting lug on the removable manway.

14. The method of claim 13, further comprising: lowering the removable manway with the lifting tool to install the removable manway in the screen opening.

15. The method of claim 14, further comprising: compressing a seal in a channel ledge surrounding the screen opening by positioning the removable manway on the channel ledge.

16. The method of claim 13, further comprising: lifting the removable manway with the lifting tool to remove the manway panel from the screen opening.

17. A removable manway for a media hold down screen, the removable manway panel comprising: a plurality of manway walls defining a manway perimeter; a screen surface; anda rotatable locking bar, wherein the rotatable locking bar is rotatable between a locking position wherein the rotatable locking bar engages the media hold down screen and an unlocked position wherein the rotatable locking bar does not extend beyond the manway perimeter.

18. The removable manway panel of claim 17, wherein the rotatable locking bar rotates around and an upwardly projecting engagement pin.

19. The removable manway of claim 18, wherein the rotatable locking bar includes a pair of upwardly projecting engagement channels located on opposed sides of the upwardly projecting engagement pin.

20. The removable man way of claim 18, wherein the rota table locking bar includes at least one locking member at an end of the rotatable locking bar.

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