Closure fitting for containment piping

A closure fitting for enclosing a portion of one or more carrier conduits between a first containment conduit section and an opposed second containment conduit section has: (a) a first cylindrical hollow body; (b) a second cylindrical hollow body, the second body being reversibly attached in fluid tight communication to the first body; (c) a first seal for sealing the first body to the first containment conduit section and a second seal for sealing the second body to the second containment conduit section, wherein and (d) a third seal for reversibly sealing the first body to the second body. In the invention, at least one of the first or second seals allows one of the bodies to axially move with respect to its containment conduit section.

FIELD OF THE INVENTION

This invention relates generally to pipe fittings, and, more specifically, to closure fittings for enclosing a portion of one or more carrier conduits between a first containment conduit section and a second containment conduit section.

BACKGROUND OF THE INVENTION

A containment conduit is often used to house one or more carrier conduits, where the carrier conduits transport hazardous materials. The purpose of the containment conduit is to contain leaks that may develop in the carrier conduits.

When one of the carrier conduits is in need of repair or when it is desired to modify one of the carrier conduits, the containment conduit surrounding that carrier conduit must be cut into to allow access to the carrier conduit. This results in an open section in the containment conduit, typically defining a first containment conduit section and an opposed second containment conduit section. After repairs or modifications are accomplished to the carrier conduit, the two containment conduit sections must be sealed to one another—to thus reestablish the overall seal of the containment conduit. Typically, a closure fitting is employed to seal the two containment sections to one another.

Also, closure fittings are frequently employed during the initial installation of a carrier conduit within a containment conduit when the containment conduit is either pre-existing or is otherwise fixed in place.

Prior art closure fittings typically comprise one or more couplings that slide over the exposed open ends of the two containment sections and seal the two containment sections to one another. It is also typical that the one or more couplings must be simultaneously cemented or welded (depending on the containment pipe material) to the exposed open ends of the containment conduit sections. The drawback to such prior art closure fitting is that it is difficult to accomplish quality simultaneous cementing or welding jobs. Also, the fully assembled closure fitting is permanently attached to the conduit sections, so that, if a problem were to develop with the repair or modification to the containment pipe, the closure fitting must be cut away and replaced.

Accordingly, there is a need for a closure fitting that provides easier assembly and can be easily separated after installation to provide access to the one or more carrier pipes.

SUMMARY OF THE INVENTION

The invention satisfies this need. One aspect the invention is a closure fitting for enclosing a portion of one or more carrier conduits between a first containment conduit section and an opposed second containment conduit section. The closure fitting comprises:

(a) a first cylindrical hollow body having a proximal end and a distal end;

(b) a second cylindrical hollow body having a proximal end and a distal end, the proximal end of the second body being reversibly attached in fluid tight communication to the proximal end of the first body;

(c) a first seal for sealing the first body to the proximal end portion of the first containment conduit section and a second seal for sealing the second body to the proximal end portion of the second containment conduit section, wherein (i) the first seal allows the first body to axially move with respect to the first containment conduit section, or (ii) the second seal allows the second body to axially move with respect to the second containment conduit section, or (iii) the first seal allows the first body to axially move with respect to the first containment conduit section and the second seal allows the second body to axially move with respect to the second containment conduit section; and

(d) a third seal for reversibly sealing the proximal end of the first body to the proximal end of the second body.

The closure fitting forms a cylinder which is capable of sealing in fluid tight fashion the proximal end portion of the first containment conduit to the proximal end portion of the second containment conduit. However, the first body and/or the second body are capable of being reversibly and axially separated from one another to allow access to one or more carrier conduits disposed between the first containment conduit and the second containment conduit.

A second aspect of the invention is a kit comprising the above described parts of the closure fitting of the invention, each part being capable of being assembled in the above described manner.

A third aspect is a method of assembling the kit of the invention to seal a pair of containment sections with the closure fitting of the invention.

The closure fitting provides a way to quickly seal the containment conduits, while at the same time it allows for easy removal to treat leaks that may develop in the carrier conduits.

DETAILED DESCRIPTION OF THE INVENTION

One aspect of the invention is a closure fitting10usable for enclosing a portion of one or more carrier conduits12between a first containment conduit section14and an opposed second containment conduit section16, wherein (1) the first containment conduit section14has a first containment section proximal end portion18terminating in an open end and the second conduit section has a second containment section proximal end portion20terminating in an open end; and (2) the first containment section proximal end portion18is opposed to and spaced apart from the open end of the second containment section proximal end portion20.

The closure fitting10comprises a first cylindrical hollow body22, a second cylindrical hollow body24, a first seal26, a second seal28, and a third seal30.

The first and second cylindrical hollow bodies22and24each have a proximal end portion32and a distal end portion34. The first seal26seals the first cylindrical body22to the proximal end portion18of the first containment conduit14. The second seal28seals the second body24to the proximal end portion20of the second containment conduit16. In one embodiment, the hollow bodies22and24are sufficiently transparent to allow visual access to their interiors.

In the invention, either (1) the first seal26allows the first body22to axially move with respect to the first containment conduit section14, (2) the second seal28allows the second body24to axially move with respect to the second containment conduit section16, or, as illustrated in the drawings, (3) the first seal26allows the first body22to axially move with respect to the first containment conduit section14and the second seal28allows the second body24to axially move with respect to the second containment conduit section16.

The third seal30reversibly seals the proximal end portion32of the first body22to the proximal end portion32of the second body24. In the embodiments of the invention illustrated in the drawings, the proximal end portion32of one of the cylindrical bodies22or24comprises a threaded proximal end36, and the third seal30comprises a gasket39such as an O-ring41, and a threaded nut38for attachment to the threaded proximal end36of the cylindrical body22or24. Other methods of providing the third seal30include, but are not limited to bolted flanges.

In the embodiment illustrated inFIGS. 1-3, the first seal26, the second seal28, or each of the first and second seals26and28comprise a seal carrier40having a cylindrical body42with a cylindrical external surface44and a cylindrical internal surface. The seal carrier40is sized and dimensioned to slip over the proximal end portion18or20of one of the containment conduit sections14or16and is attached to such containment section proximal end portion18or20in a way that the seal carrier40is sealed to the proximal end portion18or20of such containment conduit14or16.

Each of the seal carrier cylindrical external surfaces44can comprise one or more indentations46, and one or more gaskets48positioned in the one or more indentations46. The gaskets48can comprise any gasket well-known in the art, including but not limited to, O-rings50.

In the embodiment illustrated inFIGS. 1-3, the closure fitting10further comprises a pair of end caps52, each of which is attached to and surrounds the distal end34of a cylindrical body22or24. The end caps52cooperate with the seal carriers40to prevent the first body22and the second body24from sliding off of the containment conduit sections14and16.

In the embodiment illustrated inFIGS. 4-7, both the first body22and second body24define an interior surface54having one or more indentations56at their distal ends34. The first body22and second body24further comprise one or more gaskets58positioned in the one or more indentations56. The gaskets58can comprise any gasket well-known in the art, including but not limited to, O-rings60.

In the embodiment illustrated inFIGS. 4-7, the first body22and the second body24are prevented from sliding off of the first and second containment conduit sections14and16by a stop62attachable to the exterior of both the first and second containment conduit sections14and16. Each stop62can comprise a gripper ring64as illustrated inFIG. 7. Each gripper ring64has a smaller inner diameter66than the outer diameter of a containment conduit section14or16such that the gripper ring64inner diameter66bends slightly to accommodate the larger outer diameter of a containment conduit section14or16and, when slid onto a containment section14or16in a first direction, resists being slipped off of the containment section14or16in a reverse direction.

In all embodiments, the closure fitting10of the invention forms a cylinder70which is capable of sealing in fluid tight fashion the proximal end portion18of the first containment conduit section14to the proximal end portion20of the second containment conduit section16, but whereby the first body22and the second body24are capable of being reversibly and axially separated from one another to allow access to one or more carrier conduits12disposed between the first containment conduit section14and the second containment conduit section16.

A second aspect of the invention is a kit72for assembling the closure fitting10of the invention. The kit72comprises:

(a) a first cylindrical hollow body22having a proximal end32and a distal end34;

(b) a second cylindrical hollow body24having a proximal end32and a distal end34, the proximal end32of the second body24being sized and dimensioned to reversibly attach to the proximal end32of the first body22;

(c) a first seal26capable of sealing the first body22to a proximal end portion18of a first containment conduit section14and a second seal28capable of sealing the second body24to a proximal end portion20of a second containment conduit section16, wherein (i) the first seal26allows the first body22to axially move with respect to the first containment conduit section14, or (ii) the second seal28allows the second body24to axially move with respect to the second containment conduit section16, or (iii) the first seal26allows the first body22to axially move with respect to the first containment conduit section14and the second seal28allows the second body24to axially move with respect to the second containment conduit section16; and

(d) a third seal30capable of reversibly sealing the proximal end32of the first body22to the proximal end32of the second body24in fluid tight communication.

The kit72can further comprise a first seal carrier40and a second seal carrier40, as described above.

The kit72can further comprise a first seal O-ring50, a second seal O-ring50, and a third seal O-ring50as described above.

The kit72can further comprise a first end cap52and a second end cap52as also described above.

The kit72can further comprise a threaded nut38attachable to threads defined in the proximal end36of one of the cylindrical bodies.

The kit72can also comprise a pair of gripper rings64as described above.

A third aspect of the invention is a method of enclosing a portion of one or more carrier conduits12between a first containment conduit section14and a second containment conduit section16wherein (1) the first containment conduit section14has a first containment section proximal end portion18terminating in an open end and the second conduit section16has a second containment section proximal end portion20terminating in an open end; and (2) the first containment section proximal end portion18is opposed to and spaced apart from the second containment section proximal end portion20.

With the embodiment illustrated in claims1-3, the method of the invention comprises the steps of:a) providing a closure fitting kit72comprising:i) a first cylindrical hollow body22having a proximal end32and a distal end34;ii) a second cylindrical hollow body24having a proximal end32and a distal end34, the proximal end32of the second body24being sized and dimensioned to reversibly attach to the proximal end32of the first body22;iii) a first seal26sized and dimensioned for sealing the first body22to a proximal end portion18of a first containment conduit section14and a second seal28sized and dimensioned for sealing the second body24to a proximal end portion20of a second containment conduit section16, wherein (i) the first seal26allows the first body22to axially move with respect to the first containment conduit section14, or (ii) the second seal28allows the second body24to axially move with respect to the second containment conduit16section, or (iii) the first seal26allows the first body22to axially move with respect to the first containment conduit14section and the second seal28allows the second body24to axially move with respect to the second containment conduit section16;iv) wherein the first seal26comprises a first seal carrier40, the first seal carrier40having a cylindrical body42with a cylindrical external surface44and a cylindrical internal surface, and being sized and dimensioned to slip over the proximal end18of the first containment conduit section14and be attached to such containment section proximal end18in a way that the first seal carrier40is sealed to the proximal end18of such containment conduit section14;v) wherein the second seal28comprises a second seal carrier40, the second seal carrier40having a cylindrical body42with a cylindrical external surface44and a cylindrical internal surface, and being sized and dimensioned to slip over the proximal end20of the second containment conduit section16and be attached to such containment section proximal end20in a way that the second seal carrier40is sealed to the proximal end20of such containment conduit section16; andvi) a third seal30sized and dimensioned for reversibly sealing the proximal end32of the first body22to the proximal end32of the second body24in fluid tight communication;b) disconnecting all of the carrier conduits12at locations74between the first containment conduit section14and the second containment conduit section16;c) attaching the first seal carrier40to the proximal end portion18of the first containment conduit section14;d) attaching the second seal carrier40to the proximal end portion20of the second containment conduit section16;e) sliding the first cylindrical body22onto the proximal end portion18of the first containment conduit section14such that the first cylindrical body22surrounds the proximal end portion18of the first containment conduit section14and sealing the first cylindrical body22to the first containment conduit section14;f) sliding the second cylindrical body24onto the proximal end portion20of the second containment conduit section16such that the second cylindrical body24surrounds the proximal end portion20of the second containment conduit section16and sealing the second cylindrical body24to the second containment conduit section16;g) reconnecting the carrier conduits12; andh) sealing the proximal ends32of the first and second bodies22and24with the third seal30.

In this embodiment, the kit72can comprise first and second end caps52, and the method can further comprises the step of placing the first and second end caps52onto the first and second containment conduit sections14and16, respectively, after step a) and before step b), and attaching the first and second end caps52to the distal ends34of the first and second bodies22and24.

In this embodiment the third seal30can comprise a threaded nut38attachable to threads defined in the proximal end36of one of the cylindrical bodies22or24, and the method can comprise the step of sliding the threaded nut38over the non-threaded cylindrical body22or24after step f) and attaching the threaded nut38to the threaded proximal end36.

The attachment of the first seal carrier40to the first containment conduit section14and the attachment of the second seal carrier40to the second containment conduit section16can be made by a wide variety of attachment methods depending on the materials involved, especially depending on the materials of the first and second seal carriers40, and the first and second containment conduit sections14and16. Such attachment methods include, but are not limited to, stick welding, wire welding, TIG welding, brazing, soldering, solvent welding and use of adhesives (such as epoxy adhesives and urethane adhesives).

With the embodiment illustrated in claims4-7, the method of the invention comprises the steps of:

a) providing a closure fitting kit72comprising:i) a first cylindrical hollow body22having a proximal end32and a distal end34;ii) a second cylindrical hollow body24having a proximal end32and a distal end34, the proximal end32of the second body24being sized and dimensioned to reversibly attach to the proximal end32of the first body22;iii) the first body22comprising a first seal26sized and dimensioned for sealing the first body22to a proximal end portion18of a first containment conduit14and the second body24comprising a second seal28sized and dimensioned for sealing the second body24to a proximal end portion20of a second containment conduit section16, wherein (i) the first seal26allows the first body22to axially move with respect to the first containment conduit section14, or (ii) the second seal28allows the second body24to axially move with respect to the second containment conduit section16, or (iii) the first seal26allows the first body22to axially move with respect to the first containment conduit section14and the second seal28allows the second body24to axially move with respect to the second containment conduit section16;iv) a third seal30sized and dimensioned for reversibly sealing the proximal end32of the first body22to the proximal end32of the second body24in fluid tight communication;v) a first gripper ring64having a smaller inner diameter66than the outer diameter of a containment conduit section such that the first gripper ring64inner diameter66bends slightly to accommodate the larger outer diameter of a containment conduit section14or16and, when slid onto a containment section14or16in a first direction, resists being slipped off of the containment section14or16in a reverse direction; andvi) a second gripper ring64having a smaller inner diameter66than the outer diameter of a containment conduit section such that the second gripper ring64inner diameter66bends slightly to accommodate the larger outer diameter of a containment conduit section and, when slid onto a containment section14or16is a first direction, resists being slipped off of the containment section14or16in a reverse direction;

b) disconnecting all of the carrier conduits12at locations74between the first containment conduit section14and the second containment conduit section16;

c) sliding the first cylindrical body22onto the proximal end18of the first containment conduit section14such that the first cylindrical body22surrounds the proximal end18of the first containment conduit14section and sealing the first cylindrical body22to the first containment conduit section14with the first seal26;

d) sliding the second cylindrical body24onto the proximal end20of the second containment conduit16section such that the second cylindrical body24surrounds the proximal end20of the second containment conduit section16and sealing the second cylindrical body24to the second containment conduit section16with the second seal28;

e) attaching the first and second gripper rings64to the exteriors of the first and second containment conduit sections14and16, respectively;

f) reconnecting the carrier conduits12; and

g) sealing the proximal ends32of the first22and second bodies24with the third seal30.

In this embodiment the third seal30can comprise a threaded nut38attachable to threads defined in the proximal end36of one of the cylindrical bodies22or24, and the method can comprise the step of sliding the threaded nut38over the non-threaded cylindrical body22or24after step e).

The invention is advantageous in making repairs or alterations to carrier conduits. The drawback to currently used closure fittings is it is difficult to do a quality simultaneous cementing job to attach the closure fitting, and the assembly is permanent so if there is a problem the entire section must be removed and replaced.

This is especially true where thermoplastic fittings are used on thermoplastic pipes. Thermoplastic fittings are most efficiently attached to thermoplastic pipes by solvent welding. Solvent welding requires a substantial amount of time for the weld to properly cure. The time lost in having to wait for solvent welds to cure is a substantial problem. This invention avoids these problems because the closure fitting is easily attached and removed without the need for welding.

Having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.