GB2413165A

GB2413165A - Device for closing off pipes

Info

Publication number: GB2413165A
Application number: GB0408484A
Authority: GB
Inventors: Martyn James Smith
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-04-16
Filing date: 2004-04-16
Publication date: 2005-10-19
Also published as: GB0408484D0

Abstract

A device for closing off a pipe including an inflatable element 12 disposed within a casing, a portion of the casing being resiliently stretchable to engage an interior surface of the pipe. The inflatable element may be a resiliently expandable bladder with valve means 26 for allowing introduction and release of a fluid to result in inflation and deflation respectively. The casing may be formed by a cylindrical part 14 joined to two end portions 16,18 by heat sealing or by an adhesive. The joints between the cylindrical part and the end portions is preferably impervious to fluids. The device may have means 30,31 for communicating with the interior of the pipe closed off by it. The cylindrical part of the casing may be formed by a closed cell foamed material with a stretchable fabric backing.

Description

Title: Device for Closing-Off a Pipe

Description of Invention

This invention relates to a device for use in closing-off a pipe, tube, duct or the like (for all of which the term "pipe" will be used herein), the device being insertable into the pipe and including an inflatable element by means of which it can be caused to engage the internal surface of the pipe so that it is retained therein and establishes a seal therewith.

A device according to the invention is intended to be used for closing off a drainage pipe for the purpose of testing the pipe or a system incorporating same. Such testing typically involves the introduction of fluid into the pipe or system under a slightly super-atmospheric pressure and watching for leakage.

The device is provided with valve means for enabling inflation and deflation of the inflatable element, and with an appropriate fitting or fittings providing for communication with the interior of a pipe closedoff by the device, enabling a test fluid to be introduced as required.

According to the present invention there is provided a device for closingoff a pipe, including an inflatable element disposed within a casing, wherein a portion of the casing is resiliently stretchable to engage an interior surface of the pipe.

When inflated, the inflatable element may engage an interior surface of the casing to stretch the resiliently stretchable portion thereof so that it engages the interior surface of the pipe. The inflatable element may be a resiliently expandable bladder with valve means for enabling inflation and deflation thereof by introduction and release, respectively, of a fluid, preferably air. The bladder may be of a natural or synthetic rubber or rubber-like material, e.g. latex.

When the device is deflated, the casing thereof may be substantially cylindrical with opposing end portions.

The cylindrical casing may be formed by joining opposing free edges of a piece of resiliently stretchable material together to form a cylindrical part and then joining the end portions to opposite ends of the cylindrical part.

The opposing free edges of the piece of resiliently stretchable material may be joined by heat joining or an adhesive.

The end portions may be joined to the cylindrical part by stitching.

An internal surface of each end portion may be provided with a respective closure member, each closure member closing an opening in the inflatable element and providing support for the inflatable element within the casmg.

The join(s) between the cylindrical part and one of the end portions may be fluid-impervious. Thus when the casing is engaged with the interior of the pipe, fluid cannot escape from the interior of the pipe closed-off by the device through the casing. Preferably the end portion not positioned in the pipe closed-off by the device is fluid impervious.

The cylindrical part of the casing may be fluid-impervious.

Communication means may be provided for communication with the interior of a pipe closed-off by the device, thus enabling a test fluid to be introduced therein, as required.

The valve means for the flexible element may be provided on the end portion of the casing not positioned in the pipe closed-off by the device.

The cylindrical part of the casing may be a closed-cell foam material, such as, for example, a polychloroprene material (commonly known as Neoprene). The closed-cell foam material may have a backing material fixed to the interior surface thereof to improve its mechanical properties.

The end portions of the casing may be a plastics material, such as, for example, a PVC-coated woven polyester material.

The device may be used for air-testing a pipe. Thus air may be forced through the communication means and into the interior of the pipe closedoff by the device. The pipe may then be monitored for leakage.

The invention will now be described by way of example only with reference to accompanying drawing.

Referring to the drawing there is shown a cross-sectional view of device in accordance with the present invention, generally at 10. The device 10 has an inflatable element in the form of a latex bladder 12 disposed within a casing.

The casing is substantially cylindrical and has a cylindrical 14 and two I O opposing end portions 16, 18. In use the end portion 1 8 is positioned in interior of the pipe closed-off by the device 10.

The cylindrical part 14 is made from a substantially rectangular piece of closed-cell neoprene foam or similar material with a fabric backing on its interior surface such as, for example, a knitted nylon and/or other fibre stretch fabric, which is joined at two of its free edges by a heat or adhesive join (not shown) to form a cylinder. The heat or adhesive join, like the material itself, is resiliently stretchable so that when the flexible element 12 is inflated the material of the cylindrical part 14 and the joined region thereof stretch at substantially the same rate.

The end portions 16, 18 are joined to respective ends of the cylindrical part 14 by stitching 20, 21, respectively. So that fluid cannot escape from the interior of the pipe closed-off by the device 10 through the casing, the join 20 between the end portion 18 and the cylindrical part 14 is sealed with an appropriate sealant so that it is fluid-impervious. It would be adequate for the join 20 or the join 21 to be fluid- impervious, but one of them must be.

A pair of handles in the form of loops 22 of a suitable material are provided on the end of the casing not positioned in the interior of the pipe closed-off by the device 10. This allows a user to position the device 10 and remove it from the pipe when it is no longer required.

Connected to an internal surface of each end portion 16, 18 is a respective closure member in the form of a rubber support 17, 19. The rubber supports 17, 19 act as bungs closing openings in opposite ends of the bladder 12.

The end portion 16 is provided with a valve 26 which communicates with the flexible element 12, through the support 17, so that it can be inflated and deflated as required.

The device 10 includes communication means in the form of a pair of pipes 28, 29 extending through the supports 17, 19 and the flexible element 12 from the end portion 16 to the end portion 18. The end of each pipe 28, 29 terminating at the end portion 16 is provided with a respective valve 30, 31.

Fluid can be introduced into the interior of the pipe closed-off by the device 10 through the valve 30 and pipe 28 so that the pipe closed-off by the device 10 can be tested for leakage. The valve 31 and pipe 29 allow fluid to be released from the interior of the pipe closed-off by the device 10. The valve 31 in this example is a control valve which automatically releases fluid from the interior of the pipe closed-off by the device 10 if the pressure therein exceeds a predetermined level.

To close-off a pipe, such as, for example, a drainage pipe, a user must position the device 10, using the loops 22, in the interior of the pipe where required. Air or another appropriate gas is introduced into the bladder 12 through the valve 26. The bladder 12 resiliently expands until it engages the interior surface of the cylindrical part 14 of the casing. Further inflation of the bladder 12 causes the cylindrical part 14 of the casing to resiliently stretch until the external surface thereof engages the interior of the pipe closed-off by the device 10. Inflation of the bladder 12 should be continued until the user is satisfied that there is a fluid-tight seal between the exterior surface of the cylindrical part 14 and the interior surface of the pipe closed-off by the device 10.

A test fluid, conventionally air, is then introduced into the interior of the pipe closed-off by the device 10 through the valve 30 and pipe 28. This is continued whilst the pipe is being tested for leakage. If the pressure in the pipe closed-off by the device 10 exceeds a predetermined level the valve 31 automatically releases a small quantity of the fluid from the pipe until the pressure is at or below the predetermined level.

When testing of the pipe for leakage is complete the valve 31 is opened so that the pressurised fluid in the interior of the pipe closed-oft by the device is released therethrough to equalise the pressure. The valve 26 is then opened so that the bladder 12 deflates. This causes the cylindrical part 14 of the casing to disengage from the interior surface of the pipe so that the device can be removed therefrom.

Although the device 10 is generally intended for use with pipes of circular cross-section, it may be appropriately configured for use with pipes of other cross-sectional shape, for example oval.

Although described above in relation to its use in pipes, for example drainage pipes, it is to be appreciated that in being suitable for such use a device in accordance with the invention is suitable for use generally where similar or analogous requirements exist.

An advantage of a device in accordance with the present invention is that because the cylindrical part of the casing is stretchable, a single device is able to cope with closing-off a wide range of sizes of pipe.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A device for closing-off a pipe, including an inflatable element disposed within a casing, wherein a portion of the casing is resiliently stretchable to engage an interior surface of the pipe.

2. A device according to claim l wherein the inflatable element, when inflated, engages an interior surface of the casing to stretch the resiliently stretchable portion thereof so that it engages the interior of the pipe.

3. A device according to claim 1 or claim 2 wherein the inflatable element is a resiliently expandable bladder with valve means for enabling inflation and deflation thereof by introduction and release, respectively, of a fluid.

4. A device according to any preceding claim wherein when the device is deflated, the casing thereof is substantially cylindrical with opposing end portions.

5. A device according to claim 4 wherein the cylindrical casing is formed by joining opposing free edges of a piece of resiliently stretchable material together to form a cylindrical part and then joining the end portions to opposite ends of the cylindrical part.

6. A device according to claim 5 wherein the opposing free edges of the piece of resiliently stretchable material are joined by heat joining or an adhesive.

7. A device according to claim 5 or 6 wherein the join(s) between the cylindrical part and one of the end portions is fluid-impervious. l

8. A device according to claim 7 wherein the end portion not positioned in the pipe closed-off by the device is fluid impervious.

9. A device according to any one of claims 5 to 8 wherein the cylindrical part of the casing is fluid-impervious.

10. A device according to any preceding claim wherein communication means is provided for communication with the interior of a pipe closed-off by the device.

11. A device according to any one of claims 4 to 10 as appendant to claim 3 wherein the valve means for the flexible element is provided on the end portion of the casing not positioned in the pipe closed-off by the device.

12. A device according to any one of claims 5 to 11 wherein the cylindrical part of the casing is a closed-cell foam material.

13. A device according to claim 12 wherein the closed-cell foamed material has a stretchable fabric backing.

14. A device substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

15. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.