GB2216623A

GB2216623A - Pipe protection means

Info

Publication number: GB2216623A
Application number: GB8905089A
Authority: GB
Inventors: Keith Malcolm Charles Greig
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-03-05
Filing date: 1989-03-06
Publication date: 1989-10-11
Also published as: GB8905089D0

Abstract

Pipe protection means for protecting a water or other liquid-carrying pipe against bursting under freezing conditions, includes a deformable tube (1) for insertion within the pipe and being crimped and sealed at locations (4) along its length to form a plurality of tubular sections each containing compressed air, a plug (2) for push-fit connection into each open end of the tube (1) and a support member (3) formed with a recess or groove (3a) within which the plug (2) engages. The support member (3) fits within an end of the pipe to provide support for the plug (2) and thus the tube (1) when inserted into the pipe. When the water or liquid in the pipe freezes, the ice formed expands and compresses the deformable tube (1) rather than causing the pipe to burst. <IMAGE>

Description

PIPE PROTECTION MEANS The present invention relates to pipe protection means, and in particular to means for protecting pipes carrying water or other liquids under freezing conditions.

It is well known that in such conditions a water pipe can freeze and burst, this being due to ice forming and expanding inside the pipe. A pipe under such conditions becomes increasingly stressed as it is forced to expand to accommodate the greater volume of ice. Once the ice has forced the metal pipe past its limit of 'elasticity' the pipe will fracture.

Costly damage to property and plant occurs once the ice thaws and the water begins to flow once more, leaking through the fracture caused earlier by the expanding ice. Then ensues a costly clean up operation involving time, money and inconvenience.

It is an object of the present invention to provide pipe protection means which prevents water or other liquid-carrying pipes from bursting when they are frozen.

According to one aspect of the present invention there is provided pipe protection means for protecting a liquid-carrying pipe under freezing conditions, said means including a tube for insertion within said pipe, said tube being made from a deformable material and being closed at intervals along its length to form a plurality of sealed tubular sections each filled with a gas, a plug to be inserted securely into each open end of the tube, and a support member for supporting each plug within the pipe.

Preferably, each tubular section is filled with compressed air at a predetermined pressure.

The plug advantageously comprises a first portion which push fits into the open end of the tube and a second portion which extends outwardly from the tube end and is so shaped to interengage with the support member.

Preferably, the support member comprises a substantially cylindrical insert, preferably made of plastics material which is shaped and dimensioned to fit into the pipe and to conform substantially to at least part of the internal surface of the pipe. The insert is suitably formed with a recess or groove extending along its length and within which the second plug portion is accommodated. In this embodiment, the second portion preferably has a cylindrical part for engaging within the recess and being of length commensurate with the length of the recess and being provided with a flange at each end for retaining the cylindrical part within the recess. The support member is advantageously formed with an end flange for abutment against the external end face of an open end of the pipe.

According to another aspect of the present invention there is provided a kit of parts for assembly in a water or other liquid-carrying pipe for protecting the pipe against bursting under freezing conditions, said parts comprising a deformable tube for insertion within the pipe and being crimped and sealed at intervals along its length to form a plurality of tubular sections each containing compressed air, a plug for push-fit connection into each open end of the tube, and a support member arranged to engage with the plug and to fit within an end of the pipe to provide support for the plug and thus the tube, when inserted into the pipe.

The invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows schematically a side view of an embodiment of the invention, Figure 2 shows schematically a perspective view of the embodiment in Figure 1 inserted into a pipe, Figure 3 shows schematically an end view of the pipe, Figure 4 shows schematically a typical piping arrangement incorporating the present invention, and Figures 5a and 5b show schematically two crosssectional views through the pipe when in an unfrozen and frozen condition respectively.

Referring now to the Figures, a soft impermeable deformable tube 1 is crimped and sealed at locations 4 along its length to form tubular pockets, and within each pocket is trapped a suitable gas at a suitable pressure, preferably compressed air. A double-flanged plug 2 has a first portion 2a which push-fits into an open end of the tube 1. A cylindrically-shaped support clip 3 of plastics material is shaped and dimensioned to fit into an open end of a pipe 5, which is intended to carry water or any other liquid, and to conform to at least part of the internal surface of the pipe.

The clip 3 is formed with a recess or groove 3a which extends longitudinally along its length. The plug 2 has a second cylindrical portion 2b which is arranged to engage within the recess 3a, such that the clip 3 supports the plug 2, and thus the tube 1, within the pipe 5. The cylindrical portion 2b of the plug 2 is of length commensurate with the length of the recess 3a and is retained within the recess by two flanges 10 and 11 formed on the plug 2. The clip 3 is also formed with an end flange 3b which is intended to abut against an external end surface 5a of the open end of the pipe 5. The clip 3 thus firmly retains the assembly of components within the end of the pipe 5. A similar assembly to that shown in Figures 2 and 3 is repeated at the other end of the pipe 5.

Additional support clips (not shown) may also be used for supporting the tube at locations along its length within the pipe. These clips may be of similar construction to the clips 3, but without the flange 3b.

In Figure 4, there is shown an exploded view of a pipe 6 servicing a ball-valve compression fitting 7 and threaded with the crimped, sealed and pressurised deformable tube 1. Elbow compression fittings 3 retain the pipe in the required configuration. Compression fitting 8 connects the pipe 5 or the pipe protection assembly to any suitable water/liquid service pipe.

In this arrangement, the pipe length nearer the compression fitting 7 is susceptible to freezing whilst the water/liquid service at the pipe length nearer the compression fitting 4 is not susceptible to freezing.

Figures 5a and 5b show respective cross-sections of the pipe 5 containing the tube 1. Figure 5a shows the pipe in unfrozen condition carrying liquid or water 8. Figure 5b shows the pipe in frozen condition containing ice 9 which has expanded to compress the tube 1. It can thus be seen that the pressurised deformable insert tube 1 has in effect replaced a volume of liquid within the pipe by a volume of compressed air so that the pipe is never completely full of liquid. Thus when this reduced volume of liquid freezes, the ice which forms expands out of the volume previously occupied by the liquid and compresses the insert tube within the pipe, thereby preventing the pipe from bursting.Once the ice melts the air pressure within the insert tube, which is by now increased by the expanded ice, forces the wall of the tube back into its original shape. The water pressure inside the pipe and the air pressure inside the insert tube will equalize and the insert tube is once again ready to compress upon subsequent freezing.

As the insert tube is sealed, preferably every 50 cm along its length, the encapsulated pockets of compressed air are unlikely to be able to escape from the tube.

The present pipe protection means thus provides excellent protection against ice damage without added maintenance costs. It is also cheap and easy to install, and renew if accidentally damaged, and the tube can be cut to any desired length thus enabling the protection means to be used for any length of piping. As there are no complicated mechanisms the protection means is very reliable and once installed can be left in place without servicing for a considerable time. Installation is also cheap, as it requires no service costs, for example use of electricity. The components are designed for long life and the protection means has been found to reduce "hydraulic hammer" shake in susceptible pipe work.

Claims

1. Pipe protection means for protecting a liquidcarrying pipe under freezing conditions, including a tube for insertion within said pipe, said tube being made from a deformable material and being closed at intervals along its length to form a plurality of sealed tubular sections each filled with a gas, a plug to be inserted securely into each open end of the tube, and a support member for supporting each plug within the pipe.

2. Pipe protection means as claimed in claim 1, wherein each tubular section is filled with compressed air at a predetermined pressure.

3. Pipe protection means as claimed in claim 1 or 2, wherein the plug comprises a first portion which push fits into the open end of the tube and a second portion which extends outwardly from the tube end and is so shaped to interengage with the support member.

4. Pipe protection means as claimed in claim 1, 2 or 3, wherein the support member comprises a substantially cylindrical insert, which is shaped and dimensioned to fit into the pipe and to conform substantially to at least part of the internal surface of the pipe.

5. Pipe protection means as claimed in claims 3 and 4, wherein the insert is suitably formed with a recess or groove extending along its length and within which the second plug portion is accommodated.

6. Pipe protection means as claimed in claim 5, wherein the second portion has a cylindrical part for engaging within the recess and being of length commensurate with the length of the recess and being provided with a flange at each end for retaining the cylindrical part within the recess.

7. Pipe protection means as claimed in any preceding claim, wherein the support member is formed with an end flange for abutment against the external end face of an open end of the pipe.

8. Pipe protection means as claimed in any preceding claim, wherein the support member is formed from a plastics material.

9. A kit of parts for assembly in a water or other liquid-carrying pipe for protecting the pipe against bursting under freezing conditions, said parts comprising a deformable tube for insertion within the pipe and being crimped and sealed at intervals along its length to form a plurality of tubular sections each containing compressed air, a plug for push-fit connection into each open end of the tube, and a support member arranged to engage with the plug and to fit within an end of the pipe to provide support for the plug and thus the tube when inserted into the pipe.

10. Pipe protection means substantially as herein described with reference to the accompanying drawings.

11. A kit of parts substantially as herein described with reference to the accompanying drawings.