GB2080461A

GB2080461A - Improvements in or relating to pipe couplings

Info

Publication number: GB2080461A
Application number: GB8023078A
Authority: GB
Original assignee: British Steel Corp
Current assignee: British Steel Corp
Priority date: 1980-07-15
Filing date: 1980-07-15
Publication date: 1982-02-03

Abstract

The invention provides a coupling for pipes or pipe like members 1 including a unitary annular sleeve member 2 of soft metal having open ends; the wall of the sleeve member being deformed to define annular grooves 4 disposed around the inner wall of the sleeve member adjacent to the open ends thereof; a resilient elastomeric annular member 7 located in each annular groove and adapted to constitute sealing members for the coupling; and a spring washer 5 located in each annular groove and having radially inwardly extending teeth 6 which, in an unstressed condition, project beyond the internal wall of the sleeve member and are inclined in a direction axially inwardly of the sleeve member; each elastomeric member 7 being disposed on the side of the spring washer 5 nearer to the respective open end of the sleeve. <IMAGE>

Description

SPECIFICATION Improvements in or relating to pipe joints and pipe couplings This invention relates to pipe joints and pipe couplings. More particularly the invention relates to such joints and couplings for connecting pipe or pipe like members of plastics or relatively soft metals such as copper to other pipes or pipe like members or to pipe work fittings such as elbows, "T" junctions, valves, etc.

According to the invention there is provided a coupling for pipes or pipe like members including a unitary annular sleeve member of soft metal having an open end; the wall of the sleeve member being deformed to define an annular groove disposed around the inner wall of the sleeve member adjacent to the open end thereof; a resilient elastomeric annular member located in the annular groove and adapted to constitute a sealing member for the coupling; and a spring washer located in the annular groove and having radially inwardly extending teeth which, in an unstressed condition, project beyond the internal wall of the sleeve member and are inclined in a direction axially inwardly of the sleeve member; the elastomeric member being disposed on the side of the spring washer nearer to the open end of the sleeve.

By the expression "soft metal" as used herein as meant that class of easily workable metals and metal alloys of which copper is a prime and typical example.

A separating member, such as an annular disc washer, may be located in the annular groove between the elastomeric member and the spring washer to prevent interference therebetween in operation.

The spring washer may be in the form of a split ring in order to aid the fitting of the washer within its groove during assembly of the coupling.

The sleeve member may be a double ended sleeve having an internal groove with a sealing member and a spring washer adjacent each end, so as to provide a coupling member as such between two pipes or pipe like members.

Such a sleeve may be formed of a seamless, for example extruded, tube of soft metal. The wall deformations defining the internal grooves may be formed by spinning the sleeve in known manner within an external appropriately shaped die, or by pressing the sleeve in known manner upon an appropriately shaped internal collapsible mandrel.

We have found that by means of the present invention, particularly the provision of a sleeve of soft metal, we can provide a coupling which is exceptionally simple to manufacture and assemble and is exceptionally simple and convenient to assemble and use.

The resilient elastomeric annular member may be in the form of "0" ring and may be of circular or oval cross section or other sections.

With a coupling according to the invention as hereinabove defined, the joint is made by inserting a pipe (of a sliding fit) into the open end of the sleeve member. The sealing member is deformed and compressed by the pipe as it is inserted so as to provide its required sealing effect. The teeth of the spring washer are then deflected axially inwardly of the sleeve member (i.e. the direction of their original inclination) by the passage of the pipe. Any subsequent attempt to remove the pipe will tend to straighten the deflected teeth of the spring washer which will therefore bite into the pipe and resist outward movement of the pipe.

In order that the invention may be more readily understood one embodiment thereof will now be described by way of example with reference to the accompanying drawing which is a sectional elevation of a joint illustrating a coupling in accordance with the invention.

The joint shown in the figure is intended for use with, for example, a hot water pipe work system and includes two pipes 1 of cross-linked polyethylene, and a coupling connecting the two pipes including a unitary sleeve 2 formed of copper.

The pipes 1 are each provided with internal metal ferrules 3 adjacent their ends to provide greater rigidity to the pipes within the coupling.

The copper sleeve member 2 is deformed (by spinning) to provide grooves 4 at each end, the grooves 4 carrying stainless streel spring washers 5 having radially inwardly extending teeth 6 which project inwardly of the internal wall and of the sleeve member 2. The washers are in the form of split rings (not shown).

The outer grooves 4 also carry sealing members 7 in the form of "0" rings of rubber resistant to the effects of hot water such as an ethylene propylene copolymer rubber.

The sleeve member 1 is provided with a centrally located internal annular ridge 8 intended to limit the penetration of each of the pipes within the sleeve.

The coupling illustrated is assembled by springing the split ring washers 5 into grooves 4 and then pushing "0" rings 7 into the grooves.

As can be seen from the figure, each pipe 1 is a sliding fit within sleeve 2. When fitted within the sleeve 2, each pipe compresses the sealing member 7 from its normal circular cross-section thereby effecting a normal compression seal.

Movement of each pipe 1 inwardly axially of the coupling past the teeth 6 of the washer 5 has resulted in the pipe being scored as indicated at 9.

Any attempt to remove the pipe 1 from the sleeve 2 in the position indicated in the figure will tend to straighten the teeth 6 which will thereby bite further into the pipe 1 resisting removal thereof.

1. A coupling for pipes or pipe like members including a unitary annular sleeve member of soft metal having an open end; the wall of the sleeve member being deformed to define an annular groove disposed around the inner wall of the sleeve member adjacent to the open end thereof; a resilient elastomeric annular member located in the annular groove and adapted to constitute a

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to pipe joints and pipe couplings This invention relates to pipe joints and pipe couplings. More particularly the invention relates to such joints and couplings for connecting pipe or pipe like members of plastics or relatively soft metals such as copper to other pipes or pipe like members or to pipe work fittings such as elbows, "T" junctions, valves, etc. According to the invention there is provided a coupling for pipes or pipe like members including a unitary annular sleeve member of soft metal having an open end; the wall of the sleeve member being deformed to define an annular groove disposed around the inner wall of the sleeve member adjacent to the open end thereof; a resilient elastomeric annular member located in the annular groove and adapted to constitute a sealing member for the coupling; and a spring washer located in the annular groove and having radially inwardly extending teeth which, in an unstressed condition, project beyond the internal wall of the sleeve member and are inclined in a direction axially inwardly of the sleeve member; the elastomeric member being disposed on the side of the spring washer nearer to the open end of the sleeve. By the expression "soft metal" as used herein as meant that class of easily workable metals and metal alloys of which copper is a prime and typical example. A separating member, such as an annular disc washer, may be located in the annular groove between the elastomeric member and the spring washer to prevent interference therebetween in operation. The spring washer may be in the form of a split ring in order to aid the fitting of the washer within its groove during assembly of the coupling. The sleeve member may be a double ended sleeve having an internal groove with a sealing member and a spring washer adjacent each end, so as to provide a coupling member as such between two pipes or pipe like members. Such a sleeve may be formed of a seamless, for example extruded, tube of soft metal. The wall deformations defining the internal grooves may be formed by spinning the sleeve in known manner within an external appropriately shaped die, or by pressing the sleeve in known manner upon an appropriately shaped internal collapsible mandrel. We have found that by means of the present invention, particularly the provision of a sleeve of soft metal, we can provide a coupling which is exceptionally simple to manufacture and assemble and is exceptionally simple and convenient to assemble and use. The resilient elastomeric annular member may be in the form of "0" ring and may be of circular or oval cross section or other sections. With a coupling according to the invention as hereinabove defined, the joint is made by inserting a pipe (of a sliding fit) into the open end of the sleeve member. The sealing member is deformed and compressed by the pipe as it is inserted so as to provide its required sealing effect. The teeth of the spring washer are then deflected axially inwardly of the sleeve member (i.e. the direction of their original inclination) by the passage of the pipe. Any subsequent attempt to remove the pipe will tend to straighten the deflected teeth of the spring washer which will therefore bite into the pipe and resist outward movement of the pipe. In order that the invention may be more readily understood one embodiment thereof will now be described by way of example with reference to the accompanying drawing which is a sectional elevation of a joint illustrating a coupling in accordance with the invention. The joint shown in the figure is intended for use with, for example, a hot water pipe work system and includes two pipes 1 of cross-linked polyethylene, and a coupling connecting the two pipes including a unitary sleeve 2 formed of copper. The pipes 1 are each provided with internal metal ferrules 3 adjacent their ends to provide greater rigidity to the pipes within the coupling. The copper sleeve member 2 is deformed (by spinning) to provide grooves 4 at each end, the grooves 4 carrying stainless streel spring washers 5 having radially inwardly extending teeth 6 which project inwardly of the internal wall and of the sleeve member 2. The washers are in the form of split rings (not shown). The outer grooves 4 also carry sealing members 7 in the form of "0" rings of rubber resistant to the effects of hot water such as an ethylene propylene copolymer rubber. The sleeve member 1 is provided with a centrally located internal annular ridge 8 intended to limit the penetration of each of the pipes within the sleeve. The coupling illustrated is assembled by springing the split ring washers 5 into grooves 4 and then pushing "0" rings 7 into the grooves. As can be seen from the figure, each pipe 1 is a sliding fit within sleeve 2. When fitted within the sleeve 2, each pipe compresses the sealing member 7 from its normal circular cross-section thereby effecting a normal compression seal. Movement of each pipe 1 inwardly axially of the coupling past the teeth 6 of the washer 5 has resulted in the pipe being scored as indicated at 9. Any attempt to remove the pipe 1 from the sleeve 2 in the position indicated in the figure will tend to straighten the teeth 6 which will thereby bite further into the pipe 1 resisting removal thereof. CLAIMS

1. A coupling for pipes or pipe like members including a unitary annular sleeve member of soft metal having an open end; the wall of the sleeve member being deformed to define an annular groove disposed around the inner wall of the sleeve member adjacent to the open end thereof; a resilient elastomeric annular member located in the annular groove and adapted to constitute a sealing member for the coupling; and a spring washer located in the annular groove and having radially inwardly extending teeth which, in an unstressed condition, project beyond the internal wall of the sleeve member and are inclined in a direction axially inwardly of the sleeve member; the elastomeric member being disposed on the side of the spring washer nearer to the open end of the sleeve.

2. A coupling according to Claim 1 wherein the sleeve member is of copper.

3. A coupling according to Claim 1 or 2 including a separating member located in the annular groove between the elastomeric member and the spring washer to prevent interference therebetween.

4. A coupling according to Claim 3 wherein the separating member is an annular disc washer.

5. A coupling according to any one of the preceding claims wherein the spring washer is in the form of a split ring.

6. A coupling according to any one of the preceding claims wherein the sleeve member may be a double ended sleeve having an internal groove with a sealing member and a spring washer adjacent each end.

7. A coupling according to any one of the preceding claims wherein the sleeve member isian extruded tube.

8. A coupling according to any one of the preceding claims wherein the resilient elastomeric annular member is in the form of an "0" ring.

9. A coupling for pipes or pipe like members substantially as shown in and as hereinbefore described with reference to the accompanying drawing.

10. A pipe joint incorporating a coupling according to any one of the preceding claims.