Two-stage containment for operable valve

Abstract

A secondary containment system for a primary piping system having a primary piping connected by a connection point having a valve. The secondary containment system has a first shell and a second shell longitudinally separated, the first shell and the second shell being larger than and disposed around the connection point of the primary conduit. Each shell has longitudinally extending edges on opposite sides and arcuate openings at opposite ends. A sealing gasket is provided having arcuate end portions connected by a longitudinally extending strip. A series of removable clamps are used to clamp the edges of the first and second shells together with a sealing gasket sandwiched between the two shells. A valve stem adapter extends through one of the housings and is configured to rotate a valve in the primary piping system.

Description

Technical Field

[0001] The present disclosure relates to piping systems, and more particularly, to systems for containing primary piping systems. Background Art

[0002] This section provides background information related to the present disclosure which is not necessarily prior art.

[0003] The present invention relates to a secondary containment system for preventing the escape of material that may leak from a primary containment system, and in particular to a secondary containment system for a primary piping system consisting of pipes joined together in various configurations by pipe fittings having heat fused ends, pipe sockets for receiving the ends of the pipes, or threads. The secondary containment pipes are secured and sealed with the sockets to prevent fluid from leaking from the primary piping system to the atmosphere.

[0004] Protecting the environment from leaks from primary piping systems is a major issue today and is receiving increasing attention from industry and government. Increasing attention and effort is devoted to both the cleanup of existing spills and the prevention of further contamination through existing and new containment systems. The consequences of such spills are very serious, and the cost of cleanup efforts can be enormous, making the prevention of leaks of hazardous materials (typically chemicals and petroleum products, but also sewage) both environmentally and economically important.

[0005] Government regulations in the United States have expanded the requirements for secondary containment on many new facilities, such as chemical storage systems, and will require the addition of secondary containment on many existing systems in the coming years. Even now, there are existing primary piping systems that are leaking or prone to leaking, and therefore require the installation of protective secondary containment systems. Therefore, a practical and economical secondary containment system is highly desirable.

[0006] Several different approaches have been proposed to the secondary containment problem, one relatively new approach being described in U.S. Pat. No. 4,786,088. The patent discloses a dual containment thermoplastic pipe assembly including a containment pipe and a carrier pipe joined by relatively complex restraining couplings and pipe joints, some of which have a split construction to be permanently welded together around a primary pipe joint. Other secondary containment approaches are identified or discussed in the background section of this patent, as well as some generally related dual systems, connectors, etc.

[0007] Another example of a dual system is U.S. Pat. No. 4,374,596, which discloses an electrical conduit connector having pipe fittings that snap together and longitudinally separated pipe sections. U.S. Pat. No. 3,572,395 shows a substantially similar split elbow fitting. Other representative prior art secondary containment piping systems and components are shown in U.S. Pat. Nos. 3,721,270, 3,802,456, 4,422,675, and 4,673,926, all of which relate to the containment of leaks from primary pipes and fittings. The 4,673,926 patent illustrates an important auxiliary feature of such a system, namely, providing a leak detection and signaling device in the secondary containment system so that corrective action can be taken to terminate the leak from the primary system to the secondary system.

[0008] Yet another approach, used by Harrington Industrial Plastics of Los Angeles, California, and elsewhere, uses standard thermoplastic pipe and fittings of a material such as polyvinyl chloride ("PVC"), with an oversized secondary containment pipe nested over the primary pipe and attached to a conventional primary pipe joint by an oversized secondary containment fitting, which is typically cut by sawing into two pieces that can be reassembled in a clamshell fashion around the primary pipe joint. These fittings are then joined together (such as by heat welding of the sawn edges) and appropriately sealed to the secondary pipe, typically with sealing cement. Arc-shaped spacers with radially extending fingers are provided in varying sizes to maintain the two pipe systems in a spaced, coaxial relationship.

[0009] US Patent No. 5,022,685 provides another possible solution to this problem.

[0010] Despite all of these previous efforts to provide effective, practical and affordable secondary containment systems, no fully satisfactory system currently exists. Many have undue complexity and cost in manufacture, assembly or installation, and most cannot be practically applied to existing primary systems to provide effective secondary containment on a retrofit basis.

[0011] Many commercially available products are simple boxes with bolted covers that require disassembly of the box to open, close or maintain the valve. Other options include valves permanently enclosed in pipes or other valves, i.e., valves in valves, with little or no access to the valve. Summary of the invention

[0012] This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

[0013] According to one aspect of the present invention, a secondary containment system for a primary piping system is provided, the primary piping system having a primary piping connected by a connection point. The secondary containment system has a first shell and a second shell separated longitudinally, the first shell and the second shell being larger than the connection point of the primary piping and arranged around the connection point of the primary piping. A sealing gasket is provided, and a removable clamp for clamping the edges of the first shell and the second shell together, wherein the sealing gasket is sandwiched between the two shells. A valve extension adapter extends through one of the shells. The adapter has a rod, and the lower portion of the rod is configured to engage a valve in the primary piping system. An actuator that engages the upper portion of the adapter moves or rotates the adapter to cause the valve to move to an open or closed position in the primary piping system without disengaging from the sealing arrangement of the secondary containment system surrounding the primary piping system.

[0014] Further areas of applicability will become apparent from the description provided herein.The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0016] Figure 1 is an exploded perspective view of a secondary containment system made in accordance with the teachings of the present invention;

[0017] Figure 2 It is a perspective view of the secondary containment system;

[0018] Figure 3 is a perspective view of a preferred one-piece sealing gasket;

[0019] Figure 4 is a perspective view of a secondary containment system for use with a manual handle;

[0020] Figure 5 yes Figure 4 A cross-sectional view of the embodiment shown in ;

[0021] Figure 6 It is along Figure 5 a cross-sectional view taken along line 6-6;

[0022] Figure 7 is a perspective view showing a secondary containment system for use with a pneumatic actuator;

[0023] Figure 8 yes Figure 7 A cross-sectional view of the embodiment shown in ;

[0024] Fig. 9 It is along Figure 8 A cross-sectional view taken along line 9-9;

[0025] Fig.10 is a perspective view of a secondary containment system for use with an electric actuator;

[0026] Fig.11 yes Fig.10 A cross-sectional view of the embodiment shown in ;

[0027] Fig.12 It is along Fig.11 A cross-sectional view taken along line 12-12;

[0028] Fig.13 is a perspective view of a secondary containment system for use with a flange connection point for use with a butterfly valve and a pneumatic actuator; and

[0029] Fig.14 is a perspective view showing examples of several actuators that may be used interchangeably with a secondary containment system.

[0030] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0031] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0032] The terms used herein are only for the purpose of describing specific example embodiments, and are not intended to be limiting. As used herein, unless otherwise clearly indicated in the context, the singular forms "one", "an" and "the" may also be intended to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, wholes, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, parts and / or their groups. Unless explicitly identified as the order of execution, the method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or illustrated. It should also be understood that additional or alternative steps may be adopted.

[0033] When an element or layer is referred to as being "on," "engaged," "connected," or "coupled" to another element or layer, the element or layer may be directly on, directly engaged, connected, or coupled to another element or layer, or there may be intervening elements or layers. Conversely, when an element is referred to as being directly "on," "directly engaged," "directly connected," or "directly coupled" to another element or layer, there may be no intervening elements or layers. Other words used to describe relationships between elements (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.) should be interpreted in a similar manner. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] Although the terms first, second, third, etc. can be used in this article to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish one element, component, region, layer or section from another region, layer or section. Unless clearly indicated by the context, when using terms (such as "first", "second" and other numerical terms) in this article, sequence or order is not implied. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer or section discussed below may be referred to as the second element, component, region, layer or section.

[0035] For ease of description, spatially relative terms (such as "inside", "outside", "below", "below", "lower", "above", "upper", etc.) may be used herein to describe the relationship of one element or feature to another (one or more) elements or (one or more) features, as illustrated in the figure. In addition to the orientations depicted in the accompanying drawings, spatially relative terms may be intended to cover different orientations of the device in use or operation. For example, if the device in the figure is flipped, the element that is subsequently described as being "below" or "below" other elements or features is oriented as being "above" other elements or features. Therefore, the example term "below" may cover both the orientation of the above and the below. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly.

[0036] Referring now to the drawings, a secondary containment system is generally indicated by reference numeral 10. Its primary function is to enclose a primary piping system generally indicated by reference numeral 12. The primary piping system typically includes two pipes 14 and 16 connected together by a connection point 18. The connection point 18 can take a variety of forms, such as Figures 4 to 12 Alternatively, as shown in the valve 20 Fig.13As shown in the drawings, there may be a valve 86 that is mechanically connected by the pair of flanged connectors 22, 24 that fit together, or there may be no valve used as a connection point, but rather the pipes are simply fitted together by the pair of flanged connectors 22, 24. Although the pipes are shown as short pieces in the drawings, in reality, the pipes 94, 96 of the containment system 10 surround substantially the entire length of the pipes 14, 16 of the primary pipe system.

[0037] The present invention is particularly advantageous when the secondary containment system 10 surrounds a primary piping system 12 that carries toxic fluids that should not be released into the atmosphere. In such primary piping systems, it is often necessary to test the integrity of connection points or otherwise perform maintenance on connection points or other portions of the primary piping system 12. The secondary containment system 10 allows the user to perform such testing or maintenance in a simple and safe manner.

[0038] Re-reference Figure 1 and Figure 2 , the containment system 10 includes a pair of translucent mating shells 24, 26. Shell 24 includes an arcuate opening 28 for receiving a conduit 94 of the containment conduit system 10. At the opposite end of the shell 24 there is a similarly positioned arcuate opening 30 that receives the conduit 96 of the containment conduit system 10. Bridging the openings 28 and 30 are a pair of longitudinally extending edges 32 and 34 that are curved outwardly. Mating shell 26 also includes arcuate openings 36 and 38 connected together by edges 40 and 42.

[0039] The elastomeric gasket 14 is configured to seal the shells 24 and 26 together around the tubes 94, 96 that contain the piping system 10. The gasket 14 includes a pair of arcuate end members 46 and 48 that seal the containment system 10 around the tubes 94 and 96, respectively. Figure 3 As shown in FIG. 1 , each of the arcuate members 46 and 48 is preferably separate and joined together by mating dovetail ends 50 and 52. The gasket end members 46, 48 are connected together by a pair of longitudinally extending strips 50 and 52 that correspond in shape to the edges 32, 34 and 40, 42 of the shells 24 and 26, respectively.

[0040] Re-reference Figure 1 and Figure 2 , the housing 26 is provided with a receptacle 54 extending from an exterior surface of the housing 26 and surrounding an opening 56 in the housing 26. The receptacle 54 has an enlarged upper flange 58 that tapers to a neck 60 extending between the opening 56 and the flange 58. A valve stem adapter 62 includes a stem 64 extending through the neck 60. The stem 64 includes an upper fitting 66 and a lower fitting 68 for engaging the valve 20 in the primary piping system 12. A series of O-rings 70 provide a seal between the stem 64 of the valve stem adapter 62 and the neck 60 of the receptacle 54.

[0041] To assemble the secondary containment system 10 around the primary duct system 12, the gasket 14 is placed around the ducts 94, 96. Because the arcuate end members 46, 48 of the gasket 14 are separate, they can be expanded open and placed around the ducts 94, 96 and then snapped back together due to the dovetailed ends 50, 52. The shells 24, 26 are then brought together with the gasket 14 sandwiched between the shells 24, 26. The shells 24, 26 are temporarily connected together by a series of removable clamping clips, generally indicated by the reference numeral 70.

[0042] One of the advantageous features of the present invention is that the secondary containment system 10 may be used in conjunction with a variety of different types of actuators. Figures 4 to 6 A manual actuator 72 or handle is shown in FIG. Figures 7 to 9 A pneumatic actuator 74 is shown. Figures 10 to 12 The electric actuator 76 is shown in FIG. The underside of the three different actuators 72, 74 and 76 is Fig.14 . The manual actuator 72 includes a socket 78 that engages the fitting 66 on the top of the valve extension adapter 62. Likewise, the electric actuator 76 includes a socket 80 that similarly engages the fitting 66. The pneumatic actuator 74 employs a splined insert 82 that engages the fitting 66. The splines of the insert 82 engage a swivel female socket 84 in the pneumatic actuator 74.

[0043] For example, in Figure 2 and Figures 5 to 9 As shown in FIG. 8 , the lower portion of the housing 24 includes a discharge port 90 that may be sealed by a removable plug 92 .

[0044] exist Fig.13 In the embodiment of the invention, where there is a mechanically coupled valve 86 on the primary piping system, the paired flanges 22, 24 serve as connection points to the primary piping. The mechanically coupled valve 86 can be adapted to any of the actuator options 72, 74 or 76 without disrupting the seal of the secondary containment piping.

[0045] The secondary containment system 10 can be used for a variety of testing and maintenance purposes, all of which maintain the integrity of the sealed enclosure surrounding the primary piping system. Thus, leakage of fluid flowing through the primary piping system is substantially prevented from escaping the secondary containment system. Among the types of testing and maintenance that can be accomplished are low pressure leak testing of the entire secondary containment system, less than 5 psi, and valve control types 72, 74, or 76 to replace or maintain the primary piping system without destroying the sealed containment piping.

[0046] The foregoing description of the embodiments has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable where applicable and may be used in selected embodiments, even if not specifically shown or described. It may also be varied in a variety of ways. Such variations should not be considered as departing from the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

Claims

1. A secondary containment system for a primary piping system having primary pipes connected by connection points having valves, the secondary containment system comprising: a longitudinally separated first shell and a second shell, the first shell and the second shell being larger than the connection point of the primary conduit and disposed around the connection point of the primary conduit; Sealing gasket; a removable clamp for clamping edges of the first shell and the second shell together, wherein the sealing gasket is sandwiched between the two shells; and A valve extension adapter extends through one of the housings, the valve extension adapter being configured to move the valve.

2. The secondary containment system according to claim 1, further comprising: the adapter having a stem, a lower portion of the stem configured to engage the valve in the primary piping system; and An actuator engages an upper portion of the adapter for moving the adapter to cause movement of the valve in the primary piping system without disengaging a sealing arrangement of the secondary containment system surrounding the primary piping system.

3. The secondary containment system according to claim 2, wherein: The actuator is selected from the group consisting of a manual handle, a pneumatic actuator, and an electric actuator, each of which is interchangeable for engaging the adapter.

4. The secondary containment system according to claim 3, wherein: The valve extension adapter comprises: a receptacle extending from a surface of the first shell and surrounding an opening in the first shell, the receptacle having an enlarged upper flange tapering to a neck extending between the opening in the first shell and the flange, a stem extending through the neck, the stem having an outer fitting and an inner fitting for engaging the valve in the primary piping system; and A seal between the stem and the neck.

5. The secondary containment system according to claim 4, further comprising: A port in the second housing and a removable sealing plug in the port.

6. The secondary containment system according to claim 1, wherein: The sealing gasket includes arcuate end portions configured to engage an exterior surface of a pipe in the secondary piping system connected by a longitudinally extending strip sandwiched between edges of the first shell and the second shell.

7. The secondary containment system according to claim 6, wherein: The arcuate end portion of the sealing gasket is split and has interlocking ends.

8. The secondary containment system according to claim 4, wherein: The actuator is either a manual handle or an electric actuator, each having a socket for engaging the external fitting of the rod.

9. The secondary containment system according to claim 4, wherein: The actuator is a pneumatic actuator that engages an insert that fits over the outer fitting of the stem.

10. A secondary containment system for a primary piping system having primary pipes connected by connection points having valves, the secondary containment system comprising: a first shell and a second shell separated longitudinally, the first shell and the second shell being larger than the connection point of the primary pipe and disposed around the connection point of the primary pipe; each shell having longitudinally extending edges on opposite sides and having arc-shaped openings at opposite ends; a sealing gasket having arcuate end portions connected by longitudinally extending strips; and a series of removable clamps for clamping said edges of said first shell and said second shell together, wherein said sealing gasket is sandwiched between said two shells, said arcuate end portions of said sealing gasket are for sealing around a pipe of said secondary pipe system, and said longitudinally extending strips cooperate with said longitudinally extending edges of said first shell and said second shell; and A valve extension adapter extends through one of the housings, the valve extension adapter being configured to move the valve.

11. The secondary containment system according to claim 10, further comprising: the adapter having a stem, a lower portion of the stem configured to engage the valve in the primary piping system; and An actuator engages an upper portion of the adapter for moving the adapter to cause movement of the valve in the primary piping system without disengaging a sealing arrangement of the secondary containment system surrounding the primary piping system.

12. The secondary containment system according to claim 11, wherein: The actuator is selected from the group consisting of a manual handle, a pneumatic actuator, and an electric actuator, each of which is interchangeable for engaging the adapter.

13. The secondary containment system according to claim 12, wherein: The valve extension adapter comprises: a receptacle extending from a surface of the first shell and surrounding an opening in the first shell, the receptacle having an enlarged upper flange tapering to a neck extending between the opening in the first shell and the flange, a stem extending through the neck, the stem having an outer fitting and an inner fitting for engaging the valve in the primary piping system; and A seal between the stem and the neck.

14. The secondary containment system according to claim 10, further comprising: A port in the second housing and a removable sealing plug in the port.

15. The secondary containment system according to claim 10, wherein: The sealing gasket includes arcuate end portions configured to engage an exterior surface of a pipe in the secondary piping system connected by a longitudinally extending strip sandwiched between edges of the first shell and the second shell.

16. The secondary containment system of claim 15, wherein: The arcuate end portion of the sealing gasket is split and has interlocking ends.

17. The secondary containment system of claim 12, wherein: The actuator is either a manual handle or an electric actuator, each having a socket for engaging an external fitting of the rod.

18. The secondary containment system of claim 12, wherein: The actuator is a pneumatic actuator that engages an insert that fits over an outer fitting of the stem.

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