JPH04107395A - Secondary sealing device and method - Google Patents

Abstract

PURPOSE: To quickly and easily install the device and inspect the device during assembling by providing a primary pipe, a secondary sealing pipe connected by a secondary joint to partition a socket, a passage filled with an adhesive sealing compound and a sealing groove in the socket, and filling the passage with the adhesive sealing compound to form a continuous seal, thereby surrounding the internal space. CONSTITUTION: In a joint 14 surrounding a primary T-joint 12 and a pipe 15 surrounding the primary pipe 13, joint parts 17, 18 are arranged around the primary joint to surround the primary joint, thereby regulating a pipe socket 19 superposed on the pipe socket. The joint parts 17, 18 have a sealing groove 28 in the inner wall of the socket 19 which is opened at its end portion to the interior of sealing grooves 23, 24, 25 in a flange. When the end portion of the pipe 15 is fitted to the socket, a sealing path communicated with a passage is formed. When the pipe 15 is fitted to the socket and the passage is filled with adhesive sealing cement, the cement forms a continuous seal surrounding the internal space of the joint 14. As a result, complete sealing of the joint can be easily confirmed.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a secondary containment system for preventing the escape of material that may leak from a primary containment system, and more particularly to a secondary containment system which can be manufactured in various forms by means of a pipe fitting having a pipe socket for receiving the end of the pipe. Relating to a secondary containment device for a primary joint device of pipes to be joined. The pipes are installed and sealed in various sockets to prevent leakage of fluid from the primary device.

Protecting the environment from contamination due to leakage from primary containment devices is a major problem today and is receiving increasing attention from both industry and government. Increasing attention and effort is being given to both cleaning up existing spills and preventing further contamination through existing and new containment equipment. The consequences of such spills have become extremely serious, the costs of cleanup efforts can be significant, and they contain substances that are both environmentally and economically hazardous, typically chemical and petroleum products, as well as filth. It will be important to prevent the leakage of hazardous substances.

Government regulations in the United States currently require secondary containment on many new facilities, such as chemical storage devices, and will require secondary containment on many legacy devices within the next few years. Even today, there are primary piping systems that leak or are suspected of leaking and require the provision of protective secondary containment systems. Therefore, there is a significant need for a practical and economical secondary containment system.

Several different proposals have been raised to address this secondary containment problem, the most recent being U.S. Patent No. 4,786.0.
88. This patent discloses a dual containment thermoplastic pipe assembly that includes a containment pipe and a pipe joined by a relatively complex restraint fitting and pipe fitting, several pipes and a primary pipe. It is split so that it can be welded around the joint. Other secondary containment proposals are identified and discussed in the detailed description of this patent, as well as several generally related duplex devices, connectors, etc.

Another example of a dual device is Patent No. 4.374.596, which discloses an electrical duct connection having longitudinally split pipe sections and pipe fittings that snap together. ing. Patent No. 3.572.395 is
A roughly similar split elbow joint is shown. Other representative conventional secondary containment pipe devices and elements are patents Nos. 3 and 7.
No. 21,270, No. 3.802.456, No. 4.42
No. 2.675 and No. 4.673.926,
All relate to containment of leaks from primary pipes and fittings.

No. 4,673,926 exemplifies the installation of leak detectors and signaling means in the secondary containment device as an important auxiliary feature of such devices, and modifications to stop leaks from the primary device to the secondary device. can be processed.

Another proposal was made by Barrington Industrial Plastics Co., located in Los Angeles, California, and other locations.
Uses standard thermoplastic pipe and fittings in materials such as ``PVC'', which are telescopically fitted onto the pipe and joined onto conventional primary pipe fittings by oversized secondary containment fittings. Having an oversized containment pipe, the fitting is usually sawn into two pieces that are reassembled in a clamshell shape around the primary pipe fitting. In that case, these fittings are glued together, such as by hot welding of the sawn edges, and the secondary pipe is suitably sealed, usually with sealing cement. Arc-shaped spacers with radially extending fingers are provided in various sizes to maintain the two pipe systems coaxially spaced apart.

Despite all of the above prior efforts to provide an effective, practical, and reasonably priced secondary containment system, no completely satisfactory system has yet existed. Many suffer from unreasonable complexity and cost to manufacture, assemble, or install, and most cannot be practically applied to existing primary equipment to provide effective secondary containment for retrofitting older equipment.

The primary object of this invention is to meet the above-mentioned needs, to be simple and economical to construct, and to provide a quick and easy construction without the need for complex equipment, both as part of the original installation and as a retrofit device for existing primary pipe equipment. - To provide a secondary containment device that is easily installed and easily inspected during assembly and then ensures complete sealing to ensure the integrity of the device. Additionally, with the device of the invention, locating leaks in the primary device and repairing both the primary and secondary devices is easy.

For the above purpose, the present invention provides a secondary containment split joint formed by a number of joint parts, preferably two joint parts having relatively wide abutment surfaces at the parting line of the joint,
A split joint is used which has an internal sealed passage defined between the corresponding facing surfaces and an additional internal sealed passage formed as a groove in the inner surface of the pipe socket and overlapping the end of the pipe within the socket.

In the illustrated embodiment, the socket passage communicates with the passage in the abutment surface to form a continuous seal around the interior of the pipe fitting.

During assembly, the fitting sections are fitted together around the secondary containment pipe, the pipe is placed in position on the primary pipe system, and adhesive sealing cement is injected into both sets of passageways to completely enclose the interior of the fitting. It forms a fluid-tight seal and is held together until the cement hardens. The preferred method of attaching the fittings together is to form wide abutment surfaces on opposite sides of laterally projecting flanges on the fitting parts, mechanically clamping these flanges together with clips, and ensuring that the clips are at least as cemented as possible. This method allows it to be left in place until it hardens. The adhesive sealing cement is injected through a separate port opening into the passageway at the selected location, in this case into the socket groove adjacent to the intersection of the flange with the passageway, so that the cement is injected from the bottle into both sets. Flow into the passage. Preferred fitting materials are transparent and preferred cements are of a contrasting color, such as white, to permit visual visualization of the flow of cement along the path.

The interfitting surfaces center the joint portions and form a dam that confines the cement to the passageway, and an overflow area is provided to receive excess cement and reduce escape of cement from the joint.

Similarly, the invention utilizes a longitudinally segmented secondary containment pipe which is constructed from a number of elongated pipe elements, preferably two, joined edge to edge and having their abutting edges interlocked. means having mating joint means for the elements to be latched together and defining an internal sealed passage extending along the abutting edges and filled with adhesive sealing cement sealing and attaching the edges; has.

In a preferred location embodiment for the pressurizing device, the tongue and groove elements form the coupling means and the internal sealing flap on the pipe element crosses the parting line and engages the opposing pipe element butt-wise to the side coupling means. form an overlapping sealed passage. Cement is injected into the sealed passageway through longitudinally spaced openings on each side, filling the passageway and bonding the flap to the pipe element, as well as flowing into the tongue-and-groove element and bonding it as well. Glue and seal. The flap is held against the inner wall of the pipe element by internal ribs along the edge of the element, these ribs pressing the free edge of the flap tightly against the wall of the element when the elements are latched together. It is formed and arranged. The pipe elements are also made transparent so that the flow of cement along the passageway can be visually observed to confirm the completion of each seal.

The method of the invention includes the steps of providing secondary containment components of both the fitting section and the pipe element, assembling them around the fitting and pipe element of the primary pipe arrangement, and mechanically temporarily joining them together; Adhesive sealing cement is injected into the joint area to form a complete seal surrounding the interior of the joint,
injecting into the pipe element to form a side seal and observing completion of the seal as the injection progresses;
maintaining mechanical bonding of the elements at least until the cement has hardened, preferably also for a substantial hardening period. In fact, mechanical joints with economical clamps such as C-shaped clips pressed onto flanges can remain vaguely as reinforcement for glued joints.

Other aspects and advantages of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in the illustrative drawings, the present invention is embodied in a secondary containment system component, indicated generally by the reference numeral 10 for a primary containment system 11, which includes three primary containment systems. It includes a "T" fitting 12 joining pipe I3. This primary component is shown here only schematically since it is of entirely conventional construction and does not form an equivalent part of the invention.

An exemplary secondary containment component surrounds the primary tee 12.
°T'° fitting 14 and three secondary containment pipes 15 surrounding the primary pipe 13, these pipes being the same except for their length, the length of the primary pipe they surround The length of will be determined. Although a variety of materials can be used, the preferred material is a thermoplastic, particularly PvC.

This exemplary device is for a 4 inch secondary containment device that is intended for use on top of a smaller primary device. In addition to the three pipe connections of the type shown here, the apparatus of this invention is applicable to the full range of conditions found in primary containment systems. These conditions include the connection of two primary pipes with a right angle joint, such a secondary containment joint in the form of an elbow or flex joint for a normal hand being shown in FIG. 7 herein. Also available are simple sleeves with aligned, opposite-opening sockets for joining two secondary containment pipes aligned end-to-end, 45 degree elbows, and side or "Y" °° fittings and resizing fittings, as well as traps, cleaning ports, caps and other elements of a known nature, but not specifically shown in the present application; the application of the invention to these situations from the following detailed description. Methods will be readily apparent to those skilled in the art.

As best seen in FIG. 2, the preferred embodiment of the secondary containment joint 10 includes two joint sections 17, 18, which are typically molded parts and arranged around the normal hand. and are adapted to define three pipe sockets 19 which are mounted edge-to-edge and surround the primary joint and overlap pipe sockets within the primary joint. While split pipe fittings have existed in the past, such as in the aforementioned Patent No. 4.786.088 or the Harrington device, these split pipe fittings have not yet become a truly practical and effective method for assembling around a primary fitting. It was missing. For example, the two joints mentioned use hot welding or butt welding to join the edges.

According to a principal aspect of the invention, the secondary containment joint 14
The portions 17.18 have a comparatively wide abutment on the laterally projecting flanges 2021 and 22 on the dividing line of the joint, here opposite the central dividing plane passing through the axes of all three sockets of the joint. It has a face. These flanges have the effect of thickening the abutting edges of the two joint parts, with easily accessible fastening sections for use in the method described below, and with sealing grooves 23, 24, on the opposing abutment surfaces. 25, the groove is enclosed between the abutting surfaces in the assembled fitting to form a sealed passageway, which sealing passageway is filled with adhesive sealing cement 27 (see Figure 1) to hold the fitting parts together. Installed and sealed.

Furthermore, each fitting part 17,18 has a sealing groove 28 in the inner wall of each half of the socket 19, which groove extends between the flanges on opposite sides of the half socket, as shown clearly in FIGS. Extends around the socket. These sealing grooves open at their ends into sealing grooves 23, 24 and 25 in the flange. When the end of the secondary containment pipe 15 is snugly attached to one of the sockets, the grooves 28 of the half-sockets are aligned with each other and closed by the pipe on the open side, thereby enclosing the end of the pipe and the groove between the flanges. A sealed passageway is formed which communicates with the passageway formed by. When the pipe 15 is installed in each socket and the passage around the socket and between the flanges is filled with adhesive sealing cement, the cement forms a continuous, uninterrupted seal surrounding the entire interior space of the fitting 14 and seals the fitting and its The assembly of the connecting pipe 15 is completed.

Although various means can be used to secure the half-joints 17, 18 together prior to cement inflow, the presently preferred means typically secure the half-joints 17, 18 by a distance slightly less than the combined thickness of the two abutment flanges. is formed by a C-shaped strip of relatively stiff metal with spaced ends, and the lateral clamping of the flange engages a pair of simple metal clips 29 (first .
3.4 and 5). When joining flanges,
The clip is pushed partially onto the end of the flange and then driven into place with a suitable tool, such as a hammer (not shown). As shown in FIGS. 1 and 3, a clip is driven onto each end of each flange 21, 22, and two additional clips are placed along the long side of the fitting on the longer flange 20. is driven into the center part of the

The flange thus provides a thickened abutment surface as well as forming opposing clamping surfaces. External ribs (not shown) may be formed on the flange to provide a clamping surface and to prevent the clamp from sliding up and down from the flange. When the flanges are tightened together, the flanges 20.
The abutting surfaces of 21 and 22 closely and substantially seal the passageway formed between the flanges as best seen in FIG. The grooves 23, 24 and 25 forming the passageway are surrounded by opposing planes, as shown in FIG. 4, except at the entrance 30 to the groove 28 in the socket. Interdigitating rib and groove elements 31 and 32 are formed along the periphery of the flange to provide laterally facing locating surfaces for the joint portions. As shown in Figure 4,
The lower part has a rectangular rib 31 extending upward along the outer edge of the left flange 21 and a rectangular groove 32 along the outer edge of the right flange 20, and the upper joint part has the opposite; The groove 32 accommodates the rib 31 and the right rib 31 fits downwardly into the groove 32. The sides of these elements provide laterally facing locating surfaces which extend along all three flanges for optimal positioning of the two joint parts.

The outflow space is provided along the outer edge of the passageway formed by grooves 23, 24 and 25, reducing the tendency for it to escape between the abutment surfaces around the passageway by means of adhesive sealing cement. The outflow space in the flange passage is provided by a relatively deep and narrow channel 33 along the outer edge of the groove, which channel is less than a quarter of the way in size and constitutes a small amount of groove width. These channels allow excess cement to flow along the edges into deeper “wells” (w
elts)” to reduce the tendency to flow into the flanges and pass between the flanges.

In a slightly different manner, relatively shallow outflow spaces or grooves 34 are formed on either side of the central deeper groove 28, which grooves form the body of the sealed passage within the pipe socket 19.

As clearly shown in FIG. 5, these spaces allow cement to be directed from the main groove 28 towards the opposite end of the socket.

However, since the space is shallower than the central groove, the main flow follows the central groove. A shallow outflow groove is defined by walls 35 and 37 of the socket which tightly engage the pipe 15, with the end of the pipe 15 being defined by an internal shoulder 38 at the inner end of the socket.
(Fig. 5). With proper size and close proximity, escape of cement from these grooves is minimized.

It will be appreciated that dimensions will vary depending on the particular circumstances, including materials used and tolerances. By way of example only of the presently preferred embodiment, a suitable adhesive sealing cement is manufactured by Industrial Polychemical Services ("IPS"), Gardena, Calif.
is a plastic pipe cement sold under the trade name '°' PVC 719''. This product is supplied as a white, heavy thixotropic (glue-like) fluid. Suitable cements are thermosetting cements such as those sold by IPS as ``Weld On°°10''. These cements allow for a suitable total thickness of the main passageway formed by grooves 23, 24 and 25. The dimensions are on the order of 0.03 inches (0.015 inches at each flange) and a suitable overall depth for well 33 is about 50 inches (0.015 inches at each flange).
．． 025 inches). The main groove 28 within the socket 19 may be on the order of about 0.05 inch, and the shallow outflow portion 34 may be on the order of.
It is about 0.030 inches. Again, the dimensions may vary depending on the environment, and it is desirable to determine the optimal dimensions empirically for each new set of environments.

The adhesive sealing cement is injected into the two sets of passages by means of a suitable tool such as a hand gun 40 as shown in FIG. achieved. Preferably, the port has an enlarged outer end 42 for engaging the gun. In the illustrated "T" fitting, the ports are formed as countersinks drilled into the semicircular wall of the pipe socket, with one port (see Figure 4) spaced angularly above the split plane on one side. and the other port is spaced below the dividing plane on the other side.

As shown in FIG. 4, this port hole is located in a thickened small recess 43 on the outer wall of the socket.
The presently preferred spacing is about 17 degrees, which has been found to be close enough to allow good flow of cement in both directions from the ports. One flow leaves the adjacent flange and the other flow around the socket 19 is directed to the adjacent flange and enters and follows the passage therein. Fourth
Two ports formed on opposite sides of each socket as shown in the figures have been found to fill well the entire passageway within the "T" fitting shown here. However, it will be appreciated that additional ports may be formed in any passageway area not easily reached by flow simply by drilling additional holes in the outer wall of the passageway area. Also, if the cement hardens before filling is complete (for example, if work is interrupted and then restarted),
Additional ports can be drilled into unfilled areas as a precaution in this area.

Proper flow of cement along the channels formed by grooves 23, 24 and 25 is preceded by the need for air to escape from the channels. The passageway is at least initially vented by another port so that air is not trapped to impede flow. When all other ports are closed, cement is still forced into the final area to be filled, since the passageway is vented somewhat through the gaps inherent in the fabricated pipe section. The seal between the sections typically must be only tight enough to contain non-containing and relatively thick cement to avoid undesirable escape of cement. However, if there is any leakage, it can be cleaned by wiping it out at the end of the installation process. Another joint section 17° with a right angle quadratic containment normal is shown in FIG. 7 merely to illustrate the changes that can be made to create a joint of different standard configurations. The two half-sockets 19 open from the joint 90 degrees apart in exactly the same way as the two half-sockets in FIG. 6, so that the lower left flange 21 in FIG. 7 is similar to the lower left flange 21 in FIG. Although it can be the same, the flange 20 on the opposite side of the joint part is arcuate and has an arcuate groove 23 inside. In all other important respects, this joint portion 17
° is the same as the joint portion 17 in FIG. 6 and corresponding parts are designated with the same reference numerals.

In order to install the secondary containment system 10 around the primary pipe system 11 without separating the various temporary components, the pipes 15 of the secondary containment system are also arranged in a number of , preferably longitudinally divided into two elongated pipe elements 45, the pipe 1 of the primary device
Matched around 3. Although a thickened abutment surface can be provided on the pipe element and various flanged fittings for the pipe can be used, the need and length of the unflangeed end for insertion into the socket, Other practical considerations, including manufacturing cost and complexity, make it desirable to take a somewhat different approach to the design and construction of secondary containment pipes.

According to this aspect of the invention, the pipe elements 45 form an interfitting joint means for mechanically latching the elements together along their lines of abutment, and a jet seal for sealing the pipe elements together. An internal sealed passageway 47 is also defined extending longitudinally along the coupling means for receiving cement. In the presently preferred embodiment shown in FIGS. 4 and 8-1O, this coupling means includes snap-locking tongue and groove elements 48 and 49 along the abutting side edges. and an elongated internal flap 50 integrally joined to the inner surface of the pipe element along one edge of each longitudinal edge fitting and extending across the dividing plane and along the inner surface of the adjacent edge section of the other pipe element. including. The flap is spaced from the inner pipe surface along the abutting longitudinal edge, defines a sealed passageway 47, and abuts the inner pipe surface along a line 51 adjacent its free edge.

The interlocking tongue-and-groove elements are adapted to snap and latch fit and receive ribs 48 on one edge of each pipe element 45 with enlarged and slightly laterally offset free edge portions. and a groove 49 in the abutting edge of the other pipe element 45 which is shaped and positioned.

To this end, the groove has an entrance side that is slightly narrower than the free edge portion of the rib and receives the rib in an interfitting manner. The two ribs of the pipe extend across the dividing plane in opposite directions to mechanically latch the pipe elements together independent of the sealing cement.

Internal flaps 50 similarly project in the opposite direction across the dividing plane and are here formed along the same edges of the pipe element as grooves 49 and are offset inwardly from their side edges. Here, the free edge 52 of each flap has the shape of a curved bead on the outer side of the flap that is pressed into tight sealing engagement with the pipe surface to prevent cement leakage. It is preferable to provide means for keeping the amount to a minimum. In the preferred embodiment, this pressing feature has an L-shaped cross-section, opens toward the adjacent edge of the pipe element 45, receives the free end of the flap 50 when the pipe elements are pressed together, and closes the bead 52. This is done by an internal rib 53 defining an internal gutter 54 which is arranged to press against the internal pipe surface.

As shown in FIGS. 8-10, injection ports 55 are spaced apart along the pipe element and open into the internal sealed passageway 50 through the sidewall of the pipe element. These openings are drilled holes with enlarged outer ends for engagement with cement injection tools and are spaced apart by circumstances. In the presently preferred embodiment, cement from Industrial Polychemical Services, Inc. is used. with a width within the range of 75 inches from 1.015 to . For passages with gaps or thicknesses in the range of 0.5 inches, a good longitudinal spacing of the ports is on the order of 18 inches. As in the case of pipe fittings,
The preferred material is transparent PVC so that the flow of white cement along the passageway can be observed to ensure completion of the seal.

The gap between the mutually locking tongue-groove elements 48 and 49 ensures that the sealing cement injected into the internal passageway 47 under moderate injection pressure not only flows along the path between the ports but also around the helices 48 within the groove 49. The illustration is somewhat exaggerated in FIG. 9 to emphasize the inflow. This will strengthen the interlatching of the pipe elements 45 and, once the cement has hardened, will substantially permanently bond the pipe elements into a functionally integral piece.

Accordingly, the present invention provides an effective secondary containment pipe 15 made of extruded parts 45 and easily assembled around the pipes 13 of the pipe system 11 of the primary pipe system 11. Typically, this pipe is manufactured with standard wall thicknesses of around 162 inches for 4 inch pipes, with correspondingly larger wall thicknesses for larger pipes.

For purposes of illustration in FIGS. 8 and 9, a spacer 57 is shown in the secondary containment system, which is essentially conventional and of a type that supports the outer vibrator 15 generally coaxially with respect to the inner pipe 13. The spacer includes an inner arc of elastic flexure 58 extending through an arc larger than a semicircle leaving a gap on one side, and a number of radial fingers 59 projecting outwardly from the core 58. and the outer ends of the fingers are arranged on a common circle. The inner diameter of the core ("1.0°") is the outer diameter ("o, o") of a primary pipe of a given size, for example a 2-inch pipe.
), and the common circle at the tip is sized to fit the inside diameter of a given secondary containment pipe, e.g., 4 inch pipe. When installed, the spacer body is deflected to fit over the primary pipe to open a gap, then released, returned to its original shape, and tightly wrapped around the pipe. In that case, the secondary containment pipe is assembled around the primary pipe on a suitable number of spacers supporting the length of the secondary pipe, with the fingers 59 engaging the inner diameter of the secondary pipe to Hold it in place around you.

As will be apparent, a precision fit is not required and the important function is to support the two pipe devices in a generally coaxial relationship. In practice, as would be expected, secondary containment devices will be provided in a limited number of sizes, and spacers will be provided to suit all of the various sizes of primary pipe to be coated. For example, two sizes of secondary containment pipe 4
It is conceivable that the inch and 6 inch products will handle all sizes below 4 inches. Secondary pipes larger than 6 inches can be provided in some circumstances, if the manufacturing costs involved are justified.

It should be noted that the weight support of these pipe systems is a concern and appropriate care must be taken in the design of the external supports as well as the design of the spacers 57.

The radial fingers 59 of the spacer must have sufficient strength to support the load it receives. Although three angularly spaced fingers are shown here, a greater number of fingers may be provided to provide greater load carrying capability.

Other designs of pipe elements are shown in FIGS. 11-13. In FIG. 11, the abutting edges of pipe element 60 are joined by interlocking tongue and groove elements 6I and 62, tongue element 61 being a rib with an enlarged and rounded free edge portion and groove element 62 being a rib with an enlarged and rounded free edge portion. A groove having a narrower, constrained open side than the rounded portion of the rib and an enlarged inner portion defining an internal sealed passageway extending inwardly at 63. A port 64 opens into a passageway through the side wall of the pipe element 60, which side wall is preferably thickened at 65 adjacent the abutment edge with additional material inside the element.

When the passageways 62,63 of such pipe elements 60 are filled with adhesive sealing cement as in the preferred embodiment, the cement securely bonds the elements and seals the abutting edges. rib 6
Cement injected under pressure between pipe edges around 1 is expected to leak somewhat. This configuration is more suitable for use in secondary containment systems in drainage systems than in pressurized systems.

In the case of a primary device containing fluid under pressure, a reinforcing strip 67 is provided on the outer side of the pipe element 60 over the longitudinal detail between the abutting edges.
It is desirable to reinforce the secondary containment vibe of Figure U, as shown in Figure 12, by gluing. The belt 6
7 should have a concavely curved inner portion 68 for good sealing engagement with the pipe element as the cement hardens and hardens.

This outer portion need not be curved, but is shown curved here due to the transverse curvature of the entire band.

A reinforcing strip 67 of the type shown in FIG. 12 is shown in FIG. 13 as part of a secondary containment device between two secondary containment joints 69 and 70. The ends of the strip are fitted as snugly as possible between the sockets 71 and 72 of the two joints holding the vibrator, in order to completely reinforce the vibrator between the joints.

A method of assembling the secondary containment device 10 according to the present invention includes:
Although the foregoing detailed description will be obvious, a brief summary will be helpful for a thorough understanding. If this device is now applied as a retrofit of the existing primary device 11 shown in FIGS. 1 and 2, it should be understood that the two devices can be assembled simultaneously, if necessary.

As a first step, secondary containment pipe fittings and pipe element components of the type described above are suitably sized and fitted over the primary equipment components in an appropriate number and length depending on the characteristics of the primary equipment. It is provided for the purpose of matching. A spacer 57 is provided on the primary pipe 13 to fit within the secondary vibe 15 and is placed along the primary pipe J3 to receive the secondary pipe. The latter typically come in standard lengths and can be cut to suit special requirements.

With a set of spacers in place on the primary pipe 13, a secondary pipe element 45 is placed on the opposite side of the primary pipe as shown in FIG. Placed adjacent, the elements 45 are pressed together around the primary pipe until the coupling means 48,49 engage and hold the pipe elements together. The remaining secondary pipes around a given primary joint are then similarly assembled, with the secondary pipes awaiting cementing. This can be done now or delayed to occur as part of the overall cementing operation when the secondary containment joint 14 is in place. To install the fitting 14, the two fitting parts 17 and 19 are positioned in overlapping relationship with the end of the secondary pipe 15 assembled on the opposite side of the primary fitting 12, and - on the normal hand, the secondary pipe brought together around. The interdigitating ribs and grooves 31 and 32 facilitate alignment of the joint portions when brought together.

Clips 29 are then applied to the flanges 20.21 and 22 of the joint part as shown in FIGS. 1 and 3. It may be desirable to apply temporary clamps, such as locking pliers (not shown), to two or more pairs to hold the joint parts together when the clips are applied, and to remove the pliers when the joint is installed. The secondary pipe must be appropriately installed in the socket 19 of this process part relay hand.

Clamp the secondary containment fitting 14 and associated vibrator 15 in place and latch them together to connect the connecting cement to port 4.
1 to fill the sealed passage formed by the grooves 23, 24, 25 and 28 in the coupling and the passage 47 in the vibrator, together with the gaps in the coupling means 48, 49. With the filler 40 inserted into one port 4, the cement is injected into the socket groove 28 and flows in both directions around the socket and generally in each direction along and along the adjacent flange passageway towards the other port closest to the other port. It flows into the middle of the day. The progress of the cement along the path can be observed during this process and the injection pressure can be controlled to vary the flow rate. Once the area to be filled from one port has been filled, the injector is moved to the next port, and then the next port and the entire passage between the flanges in the socket are filled, allowing visual inspection of the cement through the transparent plastic. will be moved until it is confirmed by

The clip 29 must be left in place at least until the cement has hardened, preferably at least for an additional hardening period determined by the properties of the cement. PvC Vibe Cement gains a significant amount of strength in a few hours and is encouraged to cure for at least 48 hours before any substantial loading is applied.

Similarly, the flow of adhesive cement within the passageway of the secondary containment pipe 15 can be visualized to ensure that a complete, continuous, fluid-tight seal is provided. A similar setting and curing time must be provided before a load is applied to the pipe.

In this manner, the fittings and connecting pipes in the primary pipe system are continuously enclosed within the secondary containment component until the secondary system is in place. This step is substantially the same for various embodiments of the invention; the differences exist only in the structural details of the components.

As will be apparent from the foregoing, the present invention provides a new secondary containment pipe system and installation method that is significantly improved over the proposed prior art systems and components, is relatively simple to install, and To provide a functionally effective secondary containment device in which complete and effective sealing of a joint can be easily confirmed by visual inspection of cement. The components can be produced at reasonable cost using standard materials and production processes, and the result is an equally economical and highly effective secondary containment system. Additionally, an automatic leak detection device (not shown) allows the location of leaks to be visually confirmed.
crack monitoring can also be performed, and repairs can be made relatively easily both on the primary device and, if necessary, on the secondary device.

It will also be apparent that while a preferred embodiment and certain alternative embodiments have been illustrated and described in detail, various modifications and changes may be made without departing from the spirit and scope of the invention.
This invention is limited only by the scope of the appended claims and the breadth and equivalents thereof to which they are entitled.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view of a component of a secondary containment system according to the present invention shown in process of being installed onto a corresponding portion of a component of a primary containment system; be. 2 is an exploded perspective view of the components of FIG. 1 shown in somewhat schematic form with a secondary containment component separated from the primary containment component; FIG. FIG. 3 is an enlarged partial top view of the components of FIG. 4 is a further enlarged partial cross-sectional view taken in the direction of the arrow in FIG. 3 and substantially along line 4--4 in FIG. 3; FIG. 5 is an enlarged partial cross-sectional view taken substantially along line 5--5 of FIG. 3 with primary components removed for clarity of illustration. FIG. 6 is a further enlarged partial cross-sectional view taken substantially along line 6--6 of FIG. FIG. 7 is a view similar to FIG. 6, but showing an elbow fitting. FIG. 8 is an enlarged partial perspective view of a secondary containment pipe assembled with a primary containment pipe with an exemplary spacer holding the two pipes generally coaxially; FIG. FIG. 9 is an enlarged cross-sectional view taken substantially along line 9--9 of FIG. FIG. 10 is an enlarged exploded perspective view of the secondary containment pipe of FIG. 8 with the two pipe elements separated; FIG. 11 is an enlarged partial cross-sectional view similar to a portion of FIG. 9, but showing another implementation of the invention; FIG. 12 is a diagram similar to FIG. 11 showing another alternative embodiment. FIG. 13 is a partial chamber side scale view of a secondary containment pipe of the type shown in FIG. 12 extending between two secondary containment pipe joints. 10...Secondary containment device, 11...Primary containment device, 14...T joint, 15...Secondary containment pipe, 17.18...Joint part, 20.21.22.
...Flange, 23.24゜25...Contact surface sealing groove,
27... Adhesive sealing cement, 19... Socket, 2
8...Sealing groove, 29...Clip, 31.32...
- Rib-groove element, 47... Sealed passage, 45... Pipe element, 49... Groove, 52... Bead, 50...
Sealed passageway, 61.62... Tongue-groove element, 67...
Reinforcement band, 48.49...Jointing means.

Claims (1)

Claims: 1. A secondary containment device for retaining water, in particular to prevent leakage of fluid conveyed through the primary pipe system, comprising: - a primary pipe connected by at least one primary fitting (12); 13) and - surrounding the corresponding primary pipe (13) and the primary fitting (1
2) is connected by a secondary fitting (14) consisting of two fitting parts (17, 18) arranged around and designed to be joined edge-to-edge, whereby the secondary containment pipe pipe socket (19) for accommodating the end of the
- a secondary containment pipe (15) delimiting a sealing compound and a sealing groove (23) provided in said assembled fitting between the contact surfaces of the two fitting parts (17, 18);
, 24, 25) filled with an adhesive sealing compound (27) for fitting and sealing the fitting parts together; - a sealing groove (2) provided in the inner wall of each socket (19);
3, 24, 25), said passageway surrounding the end of the secondary containment pipe (15) and being filled with said adhesive sealing compound, said compound forming an uninterrupted continuous seal; and said sealing groove (28) so that the seal completely surrounds the internal space created within the coupling device (14), thereby completing the coupling pipe assembly.
and said secondary containment device. 2. The device according to claim 1, wherein the secondary joint device (14
) from which the portions (17, 18) of the flange (
a sealing groove (23, 24, 25). 3. The device according to claim 2, wherein the grooves (23, 24
, 25) is an inlet opening (30) into said sealing groove (28).
said device surrounded by opposite planes except for the planes having laterally facing cooperating elements (31-32), thereby creating complementary contact surfaces. 4. Apparatus according to any of the preceding claims, comprising means for attaching the parts (17, 18) of the secondary coupling device (14) together before applying the adhesive sealing compound. 5. Device according to claim 4, characterized in that the attachment means consist of a clamp, in particular a clamp of the clip (29) type. 6. Device according to any of the preceding claims, comprising an overflow space along the outer edge of the sealing groove (23, 24, 25). 7. Device according to any of the preceding claims, characterized in that the overflow space is capable of overflowing into "wells" arranged along the outer edges of the grooves (23, 24, 25). Said device is formed by a permissive groove (33) to allow the adhesive sealing compound to be forced through. 8. A device according to any of the preceding claims, characterized in that it is formed on both sides of said sealing groove (28) to prevent the outflow of adhesive sealing compound from said sealing groove (28) towards the opposite end of the socket (19). Said device comprising a securing groove (34). 9. Device according to any of the preceding claims, wherein a port (41) in the socket allows injection of an adhesive sealing compound. 10. Apparatus according to any of the preceding claims, wherein the sealing compound is a plastic pipe adhesive, in particular a thermosetting adhesive. 11. Apparatus according to any of the preceding claims, comprising a plurality of elongated secondary containment pipes (15) arranged on either side of one or more dividing planes and brought together around a primary pipe element (13). Said device adapted to be longitudinally divided into pipe elements (45). 12. The device according to claim 11, wherein the pipe element (45) is provided with coupling means along its contact edges, ensuring its mechanical interlocking on the one hand and sealing the passage (47) on the other hand.
), the passageway (47) extending longitudinally along said coupling means and being filled with an adhesive sealing compound ensuring attachment and sealing of said pipe element. 13. The apparatus of claim 12, wherein the coupling means comprises a rib and groove assembly element (48, 49) and an internal flap (50), the element along a lateral contact edge of the joint; Retained to each other with a snap fit, said flaps are integrally coupled to the inner surface of said pipe element (45), and a cut, spaced from the inner surface of said pipe element along a longitudinal contact edge, includes a sealing compound (47). ) said device adapted to define said passageway for use in said passage; 14. The apparatus according to claim 13, wherein each pipe element (
said rib (48) of the assembly element located on one edge of the pipe element (45) has an enlarged free edge portion and said device (49) located on the contact edge of the other pipe element (45); said device is arranged in such a way as to accommodate said rib in a snap-locking fit. 15. Apparatus according to one of claims 13 or 14, wherein the internal flap (50) is formed along the same lateral edge of the pipe element as the groove (49), and extends inwardly from the lateral edge. said device being biased to have a free edge (52) formed as a curved bead on the outer side of said flap. 16. Device according to claim 15, characterized in that the pipe elements (4
5) said device provided with means for applying and sealing said bead (52) on the surface of said device. 17. The apparatus according to claim 15, wherein the means
The free edge (52) of the flap (50) consists of internal ribs (53) of ``shaped cross-section'' that open towards the adjacent edges of said pipe elements (45) and when said pipe elements are pressed together. ) an internal gutter (54) placed to accommodate the
said device adapted to partition. 18. Apparatus according to any preceding claim, wherein the pipe elements (60) of the secondary containment pipe are held together by contact edges with the aid of rib and groove assembly elements (61, 62) held by latches. combined, said groove (62) having an enlarged lower portion defining a passage for a sealing compound (63), said groove and said passage being filled with an adhesive sealing compound retaining and sealing said contact edge; The device is configured to: 19. Device according to any of the preceding claims, characterized in that the secondary containment pipe (60) is reinforced over the longitudinal seam between the contact edges by a reinforcing strip (67) attached to the outer side of said pipe element. said device adapted to be used. 20. A method of forming a secondary containment device around a primary pipe arrangement having a primary fitting arrangement connecting at least two primary pipes, comprising: - edge-to-edge around a primary fitting (12); longitudinally for a secondary containment pipe, comprising two fitting parts (17-18) designed to fit and having at least two pipe sockets (19) for accommodating a secondary containment pipe (15). providing a split fitting (14); - defining a first internal passageway (23, 24, 25) for a sealing compound between the joining edges of said secondary fitting parts; and - a secondary containment pipe (15). - forming pipe elements (45) around the primary pipe (13) and locking them together by means of spacers (57); - the primary fitting (1);
2) Place the secondary fitting parts (17-18) around the primary pipe (23) and the secondary confinement pipe (15), grasping the fitting parts together and - interference fit inside the socket. A second internal passageway (28) for sealing compound is provided around the secondary containment pipe (15)
) - injecting a fluid adhesive sealing compound (27) into the first and second internal sealing passageways to fill the passageways and create an adhesive seal around each pipe socket between the connected edges; The operation of forming - a mechanical device to form at least said contact sealing compound (
27) maintaining grip on the secondary joint portions (17-18) until the secondary joint parts (17-18) are cured. 21. The method of claim 20, wherein after forming the first and second internal sealed passageways, the passageways communicate with each other to form a continuous passageway and sealing device, and the sealing compound is injected. Said method wherein operations are performed substantially simultaneously on both the first and second passageways for the sealing compound. 22. A method according to one of claims 20 or 21, characterized in that the pipe element is capable of being joined edge to edge around the primary pipe (13) and comprising joining means along their abutting edges. said method comprising longitudinally segmented secondary containment pipes (15) mechanically locking together and defining an internal passageway for a sealing compound extending along said coupling means; With the help of
2) locking the pipe elements (45) together around the pipe elements (45) - injecting a locking adhesive sealing compound (27) into said internal passage (47) for sealing compound to fill said passageway; forming an adhesive seal therebetween. 23. A method according to claim 22, wherein the injection operation comprises injecting the adhesive sealing compound (27) into the gap around the coupling means (48-49 or 61-62) and the pipe element (45).
said method comprising attaching together said methods. 24, controlling the formation of a seal in a sealed passageway formed between at least two pipe elements (45) or between a secondary containment pipe (15) and a secondary joint (14) attached together by an adhesive sealing compound; wherein the pipe element or fitting is constructed of a translucent or transparent material and the adhesive sealing compound of a contrasting colored liquid material, and the flow of the adhesive sealing compound within the adhesively sealed passageway is observed and controlled. Said method adapted to ensure the formation of a complete and continuous leak-tight seal.