GB2201483A

GB2201483A - Protection of water pipes

Info

Publication number: GB2201483A
Application number: GB08804556A
Authority: GB
Inventors: David Alexander Holt; David Brian Campbell; Alan James Clint
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-02-27
Filing date: 1988-02-26
Publication date: 1988-09-01
Anticipated expiration: 2008-02-26
Also published as: GB2201483B; GB8804556D0; GB8704708D0

Abstract

A water pipe system has within its pipes 14 flexible tubing 22 that will be compressed should water in the pipes expand on freezing to prevent damage to the pipes. The flexible tubing is open to the air via bleed points usually at joints 16, 18, 20 of the system to facilitate compression of the flexible tubing. <IMAGE>

Description

Title: Protection of water pipes DESCRIPTION This invention concerns protection of water pipes in freezing conditions.

One of the major problems with water supply pipes in domestic and commercial premises occurs during cold weather, namely freezing of water in pipes causing the pipes to rupture and leak upon thawing of the water. It is, therefore, recommended that water pipes be lagged with insulating material, although that is not always successful in preventing freezing.

The object of this invention is to provide means for protecting water pipes against the effects of freezing so that rupturing of the pipes is avoided.

According to the invention there is provided a method for preventing damage to a water pipe by the effects of freezing which comprises inserting into the pipe flexible tubing that can be compressed when water in the pipe freezes to take up any expansion as ice forms, the tubing being open to atmosphere at least at one end thereof.

Careful selection of tubing size according to the size of the water pipe can, therefore, mean that any expansion of water as it freezes does not put pressure on the pipe wall but rather compresses the flexible tubing which is, of course, less resistant than the pipe.

To facilitate compression of the flexible tubing, bleed points are preferably provided so that, as the tubing is compressed by ice formation, air in the tubing can escape. The bleed points are preferably provided at fairly regular intervals along a pipe system, the intervals preferably being not so long that any section of the tubing is trapped between frozen pipe sections thus preventing escape of air.

Conveniently bleed points may be provided at joints in a pipe system, for which special joints may be provided.

Accordingly the invention also provides joints for water supply pipes that incorporate bleed points for flexible tubing.

The preferred joints, ideally but not necessarily, of the compression type, include intercommunicating connection points for flexible tubing and a bleed outlet. The flexible tubing has to be well sealed to the connection points for which an adhesive that can withstand sub zero temperatures is required.

The invention will now be further described, by way of example only, with reference to the accompanying drawing which shows schematically a water pipe system and incorporates various components of the invention.

Referring to the drawing, a water supply system comprises a header tank 10 that supplies water to various outlets such as tap 12 via pipe sections 14.

The pipe sections 14 are connected at various points bycompression type pipe joints of different types, such as T-joint 16 elbow joint 18 and straight connector 20.

The pipe sections 14 each contain a length of plastics tubing 22. The tubing lengths 22 in each pipe section 14 are shown connected at the joints 16 and 20.

The T-joint 16 contains a hollow plastics or metal cross piece 24 to three ends of which lengths of plastics tubing 22 are attached by means of a suitable adhesive. The fourth end 26 of the cross piece 24 extends through the joint wall so that air in the plastics tubing can escape if the tubing is compressed.

The straight connector 20 contains a hollow T-piece 30 the stem 32 of which extends through the wall of the connector again as an air escape with the lengths of plastics tubing being connected to the arm of the T-piece.

Two further air escapes are shown firstly 34 at the header tank 10 whereat the plastics tubing extends from the pipe 14 and up through the tank to above water level. The other air escape is shown prior to the tap 12. Here a pipe connector 40 includes a hollow L-shaped piece of plastics or metal tube 42, that has the plastics tubing connected to it at one end and has its other end extending through its wall.

The purpose of the plastics tubing and the various air escapes is as follows. If water in the pipes 14 freezes, under normal circumstances the resultant expansion of the water in forming ice could cause the pipe to rupture. However, in the illustrated arrangement, any expansion of the water upon freezing is more likely to compress the plastics tubing rather than rupture the pipe. To facilitate compression of the plastics tubing the various air escape points allow the air in the tubing to escape as it is compressed.

When the ice in the pipe thaws, the plastics tubing returns to its normal size and the pipe remains unharmed.

Obviously the plastics tubing must not be so large as to impede water flow under normal conditions but it really needs to be of such a size that it can be compressed sufficiently to take up all the expansion of the water as it turns to ice. For example, for a pipe of 15mm diameter plastics tubing of internal diameter of say 4.5mm would be suitable Furthermore, instead of restricting water flow unduly, the presence of the plastics tubing in the pipes will have no obvious effect from a mains supply.

Claims

1. A method for preventing damage to a water pipe by the effects of freezing which comprises inserting into the pipe flexible tubing that can be compressed when water in the pipe freezes to take up any expansion as ice forms, the tubing being open to atmosphere at least at one end thereof.

2. A method as claimed in claim 1, wherein bleed points for the tubing are provided at intervals whereby the tubing is open to atmosphere.

3. A method as claimed in claim 2, wherein bleed points are provided at joints of the water pipe.

4. A method as claimed in claim 3, wherein said joints have intercommunicating connection points for flexible tubing and a bleed outlet.

5. A method as claimed in claim 1 and substantially as hereinbefore described with reference to the accompanying drawing.

6. A pipe joint for use in a method as claimed in any one of claims 1 to 4, the pipe joint having therein intercommunicating connection points for flexible tubing and a bleed outlet.

7. A pipe joint substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.