WO2008050075A1

WO2008050075A1 - Mains water meter

Info

Publication number: WO2008050075A1
Application number: PCT/GB2007/002876
Authority: WO
Inventors: Edward Richard Twell
Original assignee: Balfour Beatty Plc
Priority date: 2006-10-26
Filing date: 2007-07-27
Publication date: 2008-05-02
Also published as: GB0908859D0; GB0621350D0; GB2456463A; GB2443209A

Abstract

A mains water meter system comprises a water meter (32) and a fitting (34) for attaching the water meter to a stop tap body (36), such that a fluid path is defined between the stop tap input (44), through the water meter (32), and to the stop tap output (52). This enables a water meter to be installed at the location of a stop tap. This means no excavation is required to fit a water meter.

Description

MAINS WATER METER

Field of the invention

This invention relates to mains water meter systems.

Background of the invention

The use of water meters for domestic households is increasingly common. Unfortunately, the installation of water meters typically requires ground excavation between a water stop tap and the domestic premises. The stop tap defines the interface between the mains water network and the individual dwelling, and the water meter therefore needs to be installed downstream of the stop tap.

Summary of the invention

According to the invention, there is provided a mains water meter system comprising: a water meter; and a fitting for attaching the water meter to a stop tap body, such that a fluid path is defined between the stop tap input, through the water meter, and to the stop tap output.

The invention thus provides a system which enables a water meter to be installed at the location of a stop tap. This means no excavation is required to fit the water meter.

The fitting may comprise an adapter having an inner fluid passageway which terminates at an end portion for seating on the stop tap body valve seat, and an outer fluid passageway for fluid communication with the stop tap output. The inner fluid passageway then receives water from the input side of the stop tap. After this water has passed through the water meter, it can pass back into the stop tap body and to the dwelling. The inner and outer fluid passageways are preferably concentric.

The water meter may have an inner fluid input and a concentric outer fluid output. In this case, the inner fluid passageway can connect to the inner fluid input and the outer fluid passageway can connect to the outer fluid output. A simple adapter fitting can thus be defined. Instead, the water meter may have an inner fluid output and a concentric outer fluid input. In this case, the fitting may comprise a passage arrangement for connecting the inner fluid passageway to the outer fluid input and connecting the outer fluid passageway to the inner fluid output. An adapter fitting then provides a cross-over of fluid passageways.

The passage arrangement may comprise: a central duct for the inner fluid passageway for receiving water from the stop tap body, which leads to an expansion chamber for radially enlarging the inner fluid passageway, and at least one non-central passage from the expansion chamber to an input of the water meter; at least one radially diverging duct connected to a central output of the water meter, which leads to at least one radially converging duct which connects to the outer fluid passageway for returning water to the stop tap body.

This provides an arrangement for swapping passageways over which introduces low resistance paths, for example the flow path through the radially converging and radially diverging ducts can deviate by less than 60 degrees or more preferably less than 45 degrees.

The radially outermost parts of the radially diverging and radially converging ducts preferably surround the expansion chamber.

The system preferably further comprises a valve device for controlling the fluid flow between the stop tap input and the stop tap output. The normal stop tap function can thus be maintained.

The invention also provides a water installation comprising a mains water pipe, a stop tap body in the path of the pipe and a system of the invention attached to the stop tap body.

The invention also provides a method of installing a water meter, comprising: removing the stop tap valve mechanism of a stop tap between a mains water supply and a customer dwelling, thereby revealing an open stop tap body; and fitting a water meter to the open stop tap body. Brief description of the drawings

Examples of the invention will now be described in detail with reference to the accompanying drawings, in which: Figure 1 shows an arrangement of houses served by a shared mains water pipe which is to be serviced;

Figure 2 shows the known stop tap used for isolating the mains supply to each house;

Figure 3 shows a water meter system of the invention; Figure 4 shows the adapter of Figure 3 in more detail;

Figure 5 shows an alternative adapter for use in the system of the invention;

Figure 6 shows a first part of a preferred adapter design; and

Figure 7 shows a second part of the preferred adapter design of Figure 6.

Detailed description

Figure 1 shows an arrangement of houses 10 served by a shared mains water pipe 12. The mains pipe 12 is a branch from another mains pipe 14, and the supply to the branch 12 is controllable by a sluice valve 16, which can also be used to control the pressure in the branch 12 as well as completely cutting off the supply.

Stop taps 20 are shown provided in the individual branches to the houses. These stop taps 20 enable the individual supply to be cut off to enable works to be carried out to a house water system, and they typically also define the boundary between the responsibility of the water company and the responsibility of the user for the pipework.

Water meters are installed between the stop tap and the user dwelling. The installation typically involves shutting off the supply at the stop tap, and carrying out excavation works to dig to a suitable location for the water meter. If possible, water meters may also be installed in the dwellings themselves, but this may not be possible for a number of reasons. Furthermore, it may be desirable to keep the water meter out of the dwelling so that water meter readings are more easily obtained and to reduce the possibility of fraudulent tampering with the water meter. Figure 2 shows the known stop tap 20.

The left part shows the tap closed, and the shading 22 represents the mains water, which enters the mains side of the tap but is prevented by the sealing washer 24 from reaching the user side 26.

The right part shows the tap open, in which the mains side 23 is coupled to the user side 26,and the tap chamber 28 prevents water leakage.

The invention provides a water meter system which replaces the valve mechanism 28 and sealing washer 24. The valve mechanism 28 is a screw fit into a body of the stop tap, and the water meter system is designed to screw into that stop tap body.

Figures 3 shows a device 30 of the invention, comprising a water meter 32; and a fitting 34 (adapter) for attaching the water meter 32 to a stop tap body 36, in which the valve mechanism (cover, valve spindle and washer assembly) has been removed.

The fitting 34 has a threaded base 38 adapted to fit the threaded bore of the stop tap body.

The fitting 34 has an inner fluid path 40 which terminates and seals at the valve seat 42 of the stop tap body 36. This path 40 thus provides a fluid passageway from the input 44 to the stop tap body up to the water meter 32.

Figure 3 shows a water meter 32 having an inner water input 46 and a concentric outer water output 48. Thus, the fluid path 40 provides a direct coupling from the stop tap input 44 to the water meter 32.

The output 48 from the water meter connects to an outer concentric passageway 50 which is in fluid communication with the inside of the stop tap body 36, and thus connects to the stop tap body output 52. A fluid path 54 is defined between the stop tap input, up the central fluid passageway 40, through the water meter 32, and to the stop tap output 52 via the outer concentric passageway 50.

The invention thus provides a system which enables a water meter to be installed at the location of a stop tap. An interconnecting adapter interfaces between the stop tap and a mounting face of the water meter. The adapter has an outer profile which is no larger than the water meter and is as short (the height dimension in Figure 3) as possible.

No excavation is required to fit the water meter system to an existing stop tap. This can give a considerable cost saving during installation, and reduce installation time, as well as making replacement and servicing easier.

Figure 4 shows the internal fluid connection of the device of Figure 3 in more detail, and uses the same reference numbers as Figure 3. The lower end of the inner passageway 40 terminates with a flange 60 which seals over the valve seat 62. Although not shown in

Figure 4, the internal design of the stop tap body is such that the input 44 is coupled to the valve seat 62 and not to the output 52 (as shown in Figure 2). The threaded base 38 of the fitting 34 screws into the stop tap body opening, and includes passageways 64 coupling the outer fluid path 50 to the output 52.

The system of the invention can be used with existing water meters, and Figure 3 shows one example configuration with an inner fluid inlet and a concentric outer fluid outlet. However, these may be reversed in other designs of water meter.

In this case, the flow pattern between the stop tap body and the water meter needs to be altered. For this purpose, the fitting 34 can include a flow diverter as shown in Figure 5. The inner upward flow 70 from the stop tap body is routed to outer passageways 72 at a junction unit 74. The inner downward flow 76 from the water meter is routed to outer passageways 78 at a junction unit 80.

A stop tap function is still required after installation of the water meter, and this can be implemented by the fitting 34. This could be arranged as a rotating lever, other rotary device, ball valve, side plate or any other water valve device. The controller for the valve will be designed to be easily accessible without removing the water meter.

A valve control is shown schematically in Figure 3 as unit 82, and the valve 84 interrupts the flow up the inner fluid path 40. The normal stop tap function can thus be maintained.

The fitting 34 will include a sealing arrangement associated with the flange 60, and the threads and dimensions of the fitting will be designed for particular stop tap body designs. To install a water meter, a number of different fittings can be taken, which each mate and seal with the water meter, and the required fitting can then be selected based on the stop tap design found on site.

As explained briefly with reference to Figure 5, it may be required to swap inner and outer concentric fluid passageways between the stop tap body and the water meter, so that existing water meter interfaces can be used.

Figures 6 and 7 show in more detail a preferred interfacing device, for connection between the stop tap body and the water meter. The interface device has a lower body part shown in Figure 6 which connects to the stop tap and an upper body part shown in Figure 7 which connects to the water meter.

The lower body part shown in Figure 6 has a threaded part 90 at an end face for fitting to a stop tap body, in the same way as shown in Figure 3. A central tube 92 extends from the end face and has a seal 94 for closing the stop tap valve. An inner passageway is defined inside the tube 92, and an outer passageway 96 is defined around the outside of the tube.

The flow paths are shown in Figure 6 as bold arrows. Water enters the lower body part through the stainless steel tube 92.

The lower body part couples the outer passageway 96 to a pair of radially diverging/converging ducts 98 (they are diverging from the stop tap side of the body part, but they are converging with respect to the direction of fluid flow in the ducts, as shown by the bold arrows), whereas the inner passageway 92 continues straight. These ducts 98 provide the return path to the stop tap body, as shown by the bold arrows. A connection face 100 of the lower body part has a circular central portion 102 around the inner passageway, and two lugs 104 which extend radially outside the central portion 102. The connection face 100 also has a pair of bolt holes 106 at different angular positions to the lugs 104.

The upper body part shown in Figure 7 has a connection face 110 which mates with the connection face 100 of the lower body part. Seals are provided for the two ducts 98, and the seal recesses can be seen in Figure 6. The upper body part has radially diverging/converging ducts 112 which converge to a central hub 114 (they are converging from the stop tap side of the body part, but they are diverging with respect to the direction of fluid flow in the ducts, as shown by the bold arrows). These ducts open into lugs 116 corresponding to the lugs 104.

The central part of the connection face 110 has a chamber 118 which is radially larger than the inner passageway 92. One or more internal non-central passages 120 lead from a radially outermost part of this chamber through the upper body part to the face 122 for connection to the water meter.

Water enters the tube 92 as shown in Figure 6, then reaches the chamber 118. The water then passes through the tubes 120 to the input side of the water meter, attached to face 122.

The passages 120 are at different angular positions to the ducts 112 so that the ducts 112 can reach the centre of the body part. Thus, the passageways take the following paths, from the stop tap side of the joined adapater to the water meter side: the outer passageway 96 from the stop tap is branched radially outwardly in ducts and the inner passageway is expanded (by chamber 118). the ducts then converge radially to the centre, and radially outermost parts of the chamber are provided with passageways. The fluid passageway positions have in this way been swapped over. The face 122 then connects to the water meter in the same way as shown in Figure 3. Seals are provided so that the passages 120 and the central passage leading to the hub 114 are separately defined.

This design of fluid passageways reduces the pressure drop caused by swapping passageway positions. No sharp angles need to be followed by the fluid flow. For example, the ducts can diverge and then converge with less than 60 degree angle changes, and more preferably less than 45 degree angle changes. Furthermore, the two body parts can be easily machined.

Figure 7 also shows a valve mechanism, comprises an opening 130 in the central hub 114 into which a rotatable valve member 132 can be inserted, and which has a valve opening 134.

Various modifications to this design are possible. For example, any number (including 1) of passageways 120 can be used, and similarly there may could be only one duct arrangement 98,112. The connection faces can have two bolts as shown, or there may be four, or indeed any number. The valve can be housed in an opening which passes right through the body, as shown, but it does not need to do this, and there may be an opening in one side of the body which only extends to the centre.

The invention has been described as a water meter and an adapter. Of course, the two components may be integrated into a single water meter product, so that the water meter is provided "with the required interface for fitting to a particular stop tap design.

In the example shown in Figures 6 and 7, the valve 130,132 is positioned in the flow path after the water meter, namely in the return path to the stop tap body. Instead, it can be positioned before the water meter in the path from the stop tap body to the water meter.

A locking nut can be provided on the threaded base 38 to enable the device to be used with exisitng systems with different heights from the stop tap body to the valve set. The nut can include thread seals at both sides of the securing nut, so that the required sealing can be provided. Various modifications will be apparent to those skilled in the art.

Claims

. ,10Claims

1. A mains water meter system comprising: a water meter; and a fitting for attaching the water meter to a stop tap body, such that a fluid path is defined between the stop tap input, through the water meter, and to the stop tap output.

2. A system as claimed in claim 1, wherein the fitting comprises an adapter having an inner fluid passageway which terminates at an end portion for seating on the stop tap body valve seat, and an outer fluid passageway for fluid communication with the stop tap output.

3. A system as claimed in claim 2, wherein the inner and outer fluid passageways are concentric.

4. A system as claimed in claim 2 or 3, wherein the water meter has an inner fluid input and a concentric outer fluid output, the inner fluid passageway connecting to the inner fluid input and the outer fluid passageway connecting to the outer fluid output.

5. A system as claimed in claim 2 or 3, wherein the water meter has an inner fluid output and a concentric outer fluid input, and wherein the fitting comprising a passage arrangement for connecting the inner fluid passageway to the outer fluid input and connecting the outer fluid passageway to the inner fluid output.

6. A system as claimed in claim 5, wherein the passage arrangement comprises: a central duct for the inner fluid passageway for receiving water from the stop tap body, which leads to an expansion chamber for radially enlarging the inner fluid passageway, and at least one non-central passage from the expansion chamber to an input of the water meter; at least one radially diverging duct connected to a central output of the water meter, which leads to at least one radially converging duct which connects to the outer fluid passageway for returning water to the stop tap body.

7. A system as claimed in claim 6, wherein the radially outermost parts of the radially diverging and radially converging ducts surround the expansion chamber.

8. A system as claimed in claim 6 or 7, wherein the flow path through the radially converging and radially diverging ducts deviates by less than 60 degrees.

9. A system as claimed in claim 6, 7 or 8 wherein the adapter comprises two bodies, each of which comprises only straight passageways, and one body has the converging duct or ducts, and the other has the diverging duct or ducts.

10. A system as claimed in any one of claims 6 to 9, wherein the at least one passageway from a radially outermost part of the expansion chamber leading to the outer fluid output is at a different angular positions to the ducts.

11. A system as claimed in any preceding claim, further comprising a valve device for controlling the fluid flow between the stop tap input and the stop tap output.

12. A water installation comprising: a mains water pipe; a stop tap body in the path of the pipe; and a system as claimed in any preceding claim attached to the stop tap body.

13. A method of installing a water meter, comprising: removing the stop tap valve mechanism of a stop tap between a mains water supply and a customer dwelling, thereby revealing an open stop tap body; and fitting a water meter to the open stop tap body.