GB1565953A

GB1565953A - Sealing pipe joints

Info

Publication number: GB1565953A
Application number: GB4685975A
Authority: GB
Original assignee: WENROC Ltd
Current assignee: WENROC Ltd
Priority date: 1976-09-29
Filing date: 1976-09-29
Publication date: 1980-04-23

Description

(54) IMPROVEMENTS IN AND RELATING TO SEALING PIPE JOINTS (71 We, WENROC LIMITED, a British Company, of 20 Gabriels Hill, Maidstone, Kent, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to sealing pipe joints and more particularly, although not exclusively, to sealing such joints of the pipes of gas or water mains and oil pipelines.

According to the invention, there is provided a method of sealing a joint between two pipes which comprises positioning a mould around the joint, positioning and retaining an inflatable member around the mould on each axial of said joint, inflating the inflatable members so as to sucure the mould about said joint and introducing sealing compound into the mould.

Each inflatable member may be a length of inflatable tubing, closed at one end and having a valve at the other end, which is passed around the mould and retained by straps attached to each of the tubing. Such straps may comprise extensions of a woven synthetic plastics, e.g. nylon, casing for the tubing.

The inflatable member may be inflated to the desired pressure by an air compressor or other source of compressed air.

The mould may be a two-part member, which two parts may be hinged to locate around the joint and may be formed of metal, glass fibre or polyethylene.

Alternatively the mould(s) may be formed of polyvinylchloride sheeting which is wrapped around the joint to be sealed.

The invention may be more readily understood from the following description of some preferred embodiments thereof, by way of example, with reference to the accompanying drawing, in which: Fig. 1 is a side sectional view of an inflatable member; Fig. 2 is a side sectional view of a pipe joint with a flexible mould located therearound during sealing, and Fig. 3 is a side sectional view of a pipe joint with a rigid mould located therearound during sealing.

Referring firstly to Fig. 1 there is shown a tubular inflatable member 10 which is closed at one end by a stop member 11 held in position by metal straps 12 located around a synthetic plastics sleeve 13. The other end of member 10 is similarly closed but includes a tube 14, passing through stop member 11, which has a valve 15 located theein. The valve 15 may be of the form used with pneumatic tyres on motor vehicles.

The tubular member 10 has a woven synthetic plastics casing 16 located therealong which passes through sleeve 13 about stop member 11 to provide a trailing tie member 16a at one end and which is passed through sleeve 13 and back to provide a loop 16b at the end of member 10 including valve 15. Two metal rings 17 are threaded on to loop 16b prior to locating the end of casing 16 back beneath sleeve 11. A safety chain may be fitted to the ends of this device.

Referring now to Fig. 2 there is shown a pipe joint between pipes 18 and 19 with a flexible sheet form mould 20 located therearound by two inflatable members as shown in Fig. 1. This arrangement is achieved by locating a member 10 around the mould 20 at one pipe 18 by tail end 16a being threaded through rings 17. The member 10 is then inflated, for example, by attaching a compressed air line to valve 15 in tube 14. This same process is carried out at the other side of mould 20 where it surrounds pipe 19. Sealing compound can then be injected into mould 20 via injection point 21. Preferably the sealing step is carried out as disclosed in our copending United Kingdom patent application No.

31829/75 (Serial No. VOID). When the sealing compound has cured the members 10 can be deflated and removed and mould 20 removed for further use.

Fig. 3 shows a similar arrangement to Fig.

2 but in this instance the mould 20' is formed of rigid material such as steel, glass fibre or polyethylene. When steel moulds are used a strap, preferably of leather, is located around the mould on each pipe 18 and 19 prior to member 10 being located therearound, so that the metal of the mould.

cannot puncture member 10. Apart from this the sealing method is as described for Fig. 2.

WHAT WE CLAIM IS: 1. A method of sealing a joint between two pipes which comprises positioning a mould on each axial side of said joint, retaining an inflatable member around the mould on eahc actual side of said joint, inflating the inflatable members so as to secure the mould about said joint and introducing sealing compound into the mould.

2. A method as claimed in claim 1 wherein each inflatable member comprises a length of inflatable tubing, closed at one end and having a valve at the other end, which is passed around the mould and retained by straps attached to each end of the tubing.

3. A method as claimed in claim 3 wherein such straps comprise extensions of a woven synethetic plastics casing for the tubing.

4. A method as claimed in any preceding claim wherein each inflatable member is inflated to the desired pressure by an air compressor or other source of compressed air.

5. A method as claimed in any preceding claim wherein the mould is a two-part member.

6. A method as claimed in claim 5 wherein the mould parts are hinged to locate around the pipe joint.

7. A method as claimed in claim 5 or 6 wherein the mould is formed of metal, glass fibre or polyethylene.

8. A method as claimed in claim 1, 2, 3 or 4 wherein the mould is formed of polyvinylchloride sheeting which is wrapped around the joint to be sealed.

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

Claims

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

20 removed for further use.

Fig. 3 shows a similar arrangement to Fig.

2 but in this instance the mould 20' is formed of rigid material such as steel, glass fibre or polyethylene. When steel moulds are used a strap, preferably of leather, is located around the mould on each pipe 18 and 19 prior to member 10 being located therearound, so that the metal of the mould.

cannot puncture member 10. Apart from this the sealing method is as described for Fig. 2.

WHAT WE CLAIM IS: 1. A method of sealing a joint between two pipes which comprises positioning a mould on each axial side of said joint, retaining an inflatable member around the mould on eahc actual side of said joint, inflating the inflatable members so as to secure the mould about said joint and introducing sealing compound into the mould.
2. A method as claimed in claim 1 wherein each inflatable member comprises a length of inflatable tubing, closed at one end and having a valve at the other end, which is passed around the mould and retained by straps attached to each end of the tubing.
3. A method as claimed in claim 3 wherein such straps comprise extensions of a woven synethetic plastics casing for the tubing.
4. A method as claimed in any preceding claim wherein each inflatable member is inflated to the desired pressure by an air compressor or other source of compressed air.
5. A method as claimed in any preceding claim wherein the mould is a two-part member.
6. A method as claimed in claim 5 wherein the mould parts are hinged to locate around the pipe joint.
7. A method as claimed in claim 5 or 6 wherein the mould is formed of metal, glass fibre or polyethylene.
8. A method as claimed in claim 1, 2, 3 or 4 wherein the mould is formed of polyvinylchloride sheeting which is wrapped around the joint to be sealed.