GB2166506A

GB2166506A - Tapping pipe connections

Info

Publication number: GB2166506A
Application number: GB08427780A
Authority: GB
Inventors: Victor Laurence Clark
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-11-02
Filing date: 1984-11-02
Publication date: 1986-05-08
Also published as: GB8427780D0

Abstract

Improvements to retrofit fluid control valves in which the forces required to clamp and seal the two housings of the valve on to a pipe are applied by means of a separate tool. The forces applied by the separate tool are wholly or partly stored in an elastic membrane trapped in the valve housings and are retained by means of a mechanical clamp, prior to the removal of the separate tool. <IMAGE>

Description

SPECIFICATION Improvements to retrofit fluid control valves This invention relates to improvements in the construction of Retrofit fluid control valves.

A Retrofit fluid control valve is a valve which is capable of being fitted into the pipework forming a plumbing system after the system has been filled and without draining the fluid medium from the system. The valve is used to divert or control the flow of medium through the pipework. In order to gain access to and re-route the medium flowing through the pipe it is necessary to pierce the pipe and or deform the pipe after the valve has been assembled on to the pipe.

A major difficulty exsists in the construction of retro-fit valves in that it is necessary to provide a substantial clamping force between the valve body and the pipework to prevent leakage of the medium to amosphere after the pipe deformation and or the pipe piercing action has taken place. It is also necessary to retain the clamping force between the valve assembly and the pipe for many years after installation To provide an adequate clamping force between the two halves of the valve assembly and the pipework using conventional bolts or studs is difficult if the arrangement is to be aesthetically acceptable, especially in domestic central heating systems.

According to the present invention there is provided a means whereby a considerable clamping force can be provided using a separate clamping tool and a less bulky and aesthetically acceptable means of retaining those forces involving the use of a mechanical clamp and an elastic membrane which is trapped in such a way as to provide both a seal and an energy store.

A specific embodiment of the invention will now be described by way of example in which: Figure 1 shows a cross section of a valve used for diverting the flow of a medium around a restriction in a pipe via a controlled orifice which enables the flow to be regulated.

Figure 2 shows an end view of such a valve arrangement prior to it being clamped on to the pipe.

Figure 3 shows the valve body being clamped to the pipe using a separate device to provide the closing force required.

Figure 4 shows one method of retaining the separately applied clamping force.

Figure 5 shows an alternative method of retaining the separately applied clamping force.

Referring to the drawing Fig. 1 the unit comprises a lower housing 1 an upper housing 2, an upper and a lower elastic membrane 3 and a control assembly 4 comprising the pipe crushing member 5, two pipe piercing members 6 and a regulating valve 7.

When the valve is completely assembled, the elastic membranes 3 are trapped within their retaining grooves. Once trapped, elastic materials can be used to store the energy applied by the separate clamping device to provide a seal to prevent the medium escaping and to provide a clamping force between the housings 1 and 2 and the pipe 8.

Referring to the drawing Fig. 2. The upper housing 2 and lower housing 1 are being assembled on to the pipe 8. At this stage the two housings are hinged on one side by means of a retaining pin 9 passing through holes in the lugs 10 alternately positioned on the housings 1 and 2.

Referring to the drawing Fig. 3 the assembly of the housings 1 and 2 is complete. The closing force is applied using a separate clamping tool 11. Once closed the second pin 9 is fitted through holes in the lugs 10 alternately positioned on the housings 1- and 2.

When the separate clamping tool is removed, the forces applied in direction A and stored in the elastic memory of the pipe 8 and the elastic membranes 3 will be retained by reactions between the pins 9 and the lugs 10 alternately positioned on the housings 1 and 2.

Referring to the drawing Fig. 4. This shows the fully assembled unit with the control assembly 4 fitted into position.

Referring to the drawing Fig. 5 an alternative clamping method is shown whereby the forces applied by the separate clamping tool are retained by means of a wedge shaped clamp 12 passed over mating lugs 13 on the lower housing 1 and the upper housing 2.

1. A retrofit valve assembly containing a means to retain a clamping force provided by a separate clamping device.

2. A retrofit valve assembly as claimed in claim 1 whereby some or all of the clamping force, applied with a separate tool between two housings forming part of the retrofit valve assembly and the pipe, is stored by means of an elastic membrane trapped in the two housings.

3. A retrofit valve assembly as claimed in claim 1 and claim 2 whereby the stored forces are retained using a mechanical clamp.

4. A retrofit valve assembly as claimed in claim 3 whereby the mechanical clamp comprises a pin passing through holes in lugs forming part of the valve housings.

5. A retrofit valve assembly as claimed in claim 3 whereby the mechanical clamp comprises a wedge shaped clamp enclosing wedge shaped lugs forming part of the valve housings.

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements to retrofit fluid control valves This invention relates to improvements in the construction of Retrofit fluid control valves. A Retrofit fluid control valve is a valve which is capable of being fitted into the pipework forming a plumbing system after the system has been filled and without draining the fluid medium from the system. The valve is used to divert or control the flow of medium through the pipework. In order to gain access to and re-route the medium flowing through the pipe it is necessary to pierce the pipe and or deform the pipe after the valve has been assembled on to the pipe. A major difficulty exsists in the construction of retro-fit valves in that it is necessary to provide a substantial clamping force between the valve body and the pipework to prevent leakage of the medium to amosphere after the pipe deformation and or the pipe piercing action has taken place. It is also necessary to retain the clamping force between the valve assembly and the pipe for many years after installation To provide an adequate clamping force between the two halves of the valve assembly and the pipework using conventional bolts or studs is difficult if the arrangement is to be aesthetically acceptable, especially in domestic central heating systems. According to the present invention there is provided a means whereby a considerable clamping force can be provided using a separate clamping tool and a less bulky and aesthetically acceptable means of retaining those forces involving the use of a mechanical clamp and an elastic membrane which is trapped in such a way as to provide both a seal and an energy store. A specific embodiment of the invention will now be described by way of example in which: Figure 1 shows a cross section of a valve used for diverting the flow of a medium around a restriction in a pipe via a controlled orifice which enables the flow to be regulated. Figure 2 shows an end view of such a valve arrangement prior to it being clamped on to the pipe. Figure 3 shows the valve body being clamped to the pipe using a separate device to provide the closing force required. Figure 4 shows one method of retaining the separately applied clamping force. Figure 5 shows an alternative method of retaining the separately applied clamping force. Referring to the drawing Fig. 1 the unit comprises a lower housing 1 an upper housing 2, an upper and a lower elastic membrane 3 and a control assembly 4 comprising the pipe crushing member 5, two pipe piercing members 6 and a regulating valve 7. When the valve is completely assembled, the elastic membranes 3 are trapped within their retaining grooves. Once trapped, elastic materials can be used to store the energy applied by the separate clamping device to provide a seal to prevent the medium escaping and to provide a clamping force between the housings 1 and 2 and the pipe 8. Referring to the drawing Fig. 2. The upper housing 2 and lower housing 1 are being assembled on to the pipe 8. At this stage the two housings are hinged on one side by means of a retaining pin 9 passing through holes in the lugs 10 alternately positioned on the housings 1 and 2. Referring to the drawing Fig. 3 the assembly of the housings 1 and 2 is complete. The closing force is applied using a separate clamping tool 11. Once closed the second pin 9 is fitted through holes in the lugs 10 alternately positioned on the housings 1- and 2. When the separate clamping tool is removed, the forces applied in direction A and stored in the elastic memory of the pipe 8 and the elastic membranes 3 will be retained by reactions between the pins 9 and the lugs 10 alternately positioned on the housings 1 and 2. Referring to the drawing Fig. 4. This shows the fully assembled unit with the control assembly 4 fitted into position. Referring to the drawing Fig. 5 an alternative clamping method is shown whereby the forces applied by the separate clamping tool are retained by means of a wedge shaped clamp 12 passed over mating lugs 13 on the lower housing 1 and the upper housing 2. CLAIMS