WO2001002760A1

WO2001002760A1 - A hydrant valve

Info

Publication number: WO2001002760A1
Application number: PCT/AU2000/000731
Authority: WO
Inventors: Frank Ronald Graham; Thomas John Simpson; Peter William Devellerez; Peter Barnes Verschuer
Original assignee: Water Corporation
Priority date: 1999-06-29
Filing date: 2000-06-29
Publication date: 2001-01-11
Also published as: GB2367603A; GB2367603B; AUPQ125699A0; GB0130562D0

Abstract

A water hydrant valve (10) comprising a hollow body portion (12) with a water inlet (44) and a water outlet (46) and a sealing member (16) arranged to move between the water inlet (44) and the water outlet (46). The valve (10) is arranged so when water pressure is higher in the water main (60) than the feed pipe (58) the sealing member (16) seals against the water outlet (46) and requires an actuation means (70) to open the valve, and when water pressure is higher in the feed pipe (58) than the water main (60) the sealing member (16) seals against the water inlet (44) and thus prevents backflow into the water main (60).

Description

TITLE

"A HYDRANT VALVE" FIELD OF THE INVENTION

The present invention relates to a hydrant valve for use in a hydrant of a water distribution system.

It is common in a water distribution system to provide fire hydrants at regularly spaced locations in the system so that there is always a hydrant in close proximity to a house fire irrespective of the location of the fire. One such hydrant commonly in use includes a valve of the type having a sealing member resiliently biased in an upward direction towards a sealing position. The valve is opened by manually forcing the sealing member to move downwardly away from the sealing position.

However, with such a valve, there is no provision for safeguarding against water passing downwardly back through the valve. Under normal operating conditions of the valve, the pressure in the water distribution system is greater than the pressure outside the water distribution system and the valve is urged by the water pressure to a closed position. In some circumstances, however, it is possible for the pressure outside the water distribution system to rise above the pressure in the water distribution system, resulting in a tendency of water to flow downwardly back through the valve. This is generally undesirable since the returning water contains contaminated matter which may constitute a public health risk. This problem is partially overcome by an alternative valve which operates on the same principle as a common household tap or faucet. The valve includes a rotatable spindle and a sealing disc disposed in line with and between the spindle and a water inlet Rotation of the spindle in a first sense biases the disc downwardly against the water inlet to seal the water inlet, and rotation of the spindle in a second sense releases the biasing force from the disc and water is free to flow upwardly past the disc towards a water outlet If the water pressure outside the water distribution system rises above the water pressure inside the water distribution system, water tends to flow downwardly back through the water outlet and towards the water inlet. To restrict such flow, the weight of the returning water acts against the disc and urges the disc to close the water inlet

However, while features are included in the alternative valve to restrict backflow of water, with this valve backflow prevention is unreliable as the seal between the sealing disc and the inlet aperture is weak.

The present invention seeks, therefore, among other things, to provide a hydrant valve which improves on the hydrant valves known hitherto.

SUMMARY OF THE PRESENT INVENTION In accordance with one aspect of the present invention, there is provided a hydrant valve characterised in that it comprises a hollow body portion having a water inlet and a water outlet, the body portion defining a cavity and a sealing member being disposed in the cavity, wherein the sealing member is moveable between the water inlet and the water outlet; the sealing member is arranged to engage sealingly with the water inlet or the water outlet when the sealing member is located adjacent the water inlet or the water outlet respectively, the sealing member, under normal operating conditions when the hydrant is not required for use, is urged by water pressure into sealing engagement with the water outlet, mechanical means is provided for disengaging the sealing member from the water outlet when the hydrant is required for use, and the sealing member, under conditions of use where water pressure at a feed pipe exceeds water pressure a water main, is urged into sealing engagement with the water inlet

In this way, a hydrant valve is provided which more effectively prevents backflow of water to the water inlet than hydrant valves known hitherto

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described, by way of example, with reference to the accompanying drawings, in which -

Figure 1 is a diagrammatic side view in cross section of a hydrant valve in accordance with the present invention,

Figure 2 is a diagrammatic cross sectional view taken along the line II-II of Figure 1 in the direction of the arrows,

Figure 3 is a diagrammatic cross sectional view of a hydrant including the hydrant valve of Figures 1 and 2 with the hydrant connected to a water main and connected, in use, to a water feed pipe,

Figure 4a is a diagrammatic side view in cross section of the hydrant valve shown in Figures 1 and 2 with a sealing member of the hydrant valve in a first sealing position, and Figure 4b is a diagrammatic side view in cross section of the hydrant valve shown in Figures 1 and 2 with the sealing member of the hydrant valve in a second sealing position

DESCRIPTION OF THE INVENTION Referring to Figures 1 and 2 of the drawings, there is shown a hydrant valve 10 which includes a valve body 12 defining a cavity 14, a sealing member in the form of a substantially elliptoid shaped jockey 16, and guiding means in the form of a guiding cage 18 The valve body 12 includes a substantially spherical body portion 20, a first collar portion 22 disposed at a first end of 13 the body portion 20, a second collar portion 24 disposed at a second end 15 of the body portion 20 and a support ring 26 extending circumferentially of the body portion 20

The jockey 12 has a first longitudinal end 17 oriented towards the first end 13 of the body portion 20 and a second longitudinal end 19 oriented towards the second end 15 of the body portion 20

Provided adjacent the first and second longitudinal ends 17, 19 of the jockey 16 are first sealing means in the form of first and second Annular seals 28 and 29 respectively Also provided at the first and second longitudinal ends 17, 19 of the jockey 16 are first and second engagement recesses 30 and 32 respectively Extending substantially longitudinally of the jockey 16 are four channels 34 configured so as to slidably engage with the guiding cage 18

The guiding cage 18 includes four guides 36 extending substantially longitudinally of the hydrant valve 10, the guides 36 being disposed relative to each other so as to correspond with the locations of the channels 34 on the jockey 16 Although four channels 34 and four guides 36 are provided in the present example, it will be understood that an alternative corresponding number of channels 34 and guides 36 may be provided, the important aspect being that the channels 34 and the guides 36 co-operate with each other so as to permit substantially free movement of the jockey 16 in a longitudinal direction and to substantially restrict movement of the jockey 16 in other directions

The guiding cage 18 also includes a first annular end portion 38 at the first end 13 of the body portion 20 and a second annular end portion 40 at the second end 15 of the body portion 20 which serve to hold the guides 36 in position relative to each other The guiding cage 18 is configured so as to fit snugly in the first and second collar portions 22, 24 of the valve body 12

It will be appreciated that the guiding cage 18 could be constructed in a variety of ways In this example, the first annular end portion 38 is formed in one piece with half of the four guides 36 and the second annular end portion 40 is formed in one piece with the other half of the guides 36, the two halves of the guiding cage 18 being fixed together by joining free ends of the guides 36 by any appropriate means In the present example, locating pins 42 are also provided for this purpose The hydrant valve 10 also includes a water inlet 44 disposed adjacent the first end 13 and a water outlet 46 disposed adjacent the second end 15 Also provided are first and second end caps 48 and 50 respectively disposed adjacent the water inlet 44 and the water outlet 46 respectively The first and second end caps 48, 50 may each be provided with an internally screw threaded portion (not shown) which is adapted to engage with an externally screw threaded portion provided on each of the first and second collar portions 22, 24 so as to sealably fix the water inlet 44 and the water outlet 46 relative to the valve body 12 Alternatively, one of the first or second end caps 48, 50 may be provided with an internally screw threaded portion and the other first or second end cap 48, 50 may be fixed in position relative to the first or second collar portion 22, 24 It will be appreciated that the first and second end caps 48, 50 may be sealing connected to the first and second collar portions 22, 24 by other suitable means, for instance by welding

In this example, the hydrant valve 10 also includes second sealing means in the form of first and second annular sealing rings 52 and 54 respectively, the first annular sealing ring 52 being disposed intermediate the water inlet 44 and the guiding cage 18 and the second annular sealing ring 54 being disposed intermediate the water outlet 46 and the guiding cage 18

It will be appreciated that although in the present example the guiding cage 18 and the body portion 20 are shown as separate members, the guiding cage 18 and the body portion 20 may be integral with each other Referring to Figure 3, there is shown a hydrant 56 connected, in use, to a water feed pipe 58, the hydrant 56 also being connected to a water main 60 The hydrant 56 includes a live tapping band 62, a full way isolating valve 64 for manually opening or closing the hydrant 56, an extension tube 66 extending upwardly of the full way isolating valve 64 to the hydrant valve 10, and a hydrant BIC (British

Instantaneous Coupling) connection 68 connected to the water outlet 46 of the hydrant valve 10 It will be appreciated 56 that the hydrant may be connected to the water main 60 by other suitable means

As shown in Figure 3, in use, a water feed pipe 58 is connected to the hydrant 56 at the hydrant BIC connection 68, the water feed pipe 58 including an actuating means in the form of a rotatable control spindle 70 having a handle 72 at one end and a nipple 74 at the other end The arrangement is such that the nipple 74 engages, in use, with the second engagement recess 32 in the jockey 16 and rotation of the control spindle 70 in a clockwise direction effects downward movement of the jockey 16 The hydrant valve 10 now will be described in use in relation to Figures 4a and 4b In normal use of the hydrant valve 10, the hydrant valve 10 forms part of a hydrant 56 as shown in Figure 3 The full way isolating valve 64 is open As a result of the pressure of water in the water main 60, an upward force in the direction of the arrow

in Figure 4a is exerted on the jockey 16 and the jockey 16 moves upwardly of the cage 18 until the jockey 16 contacts the second annular end portion 40 In this position, the second Annular seal 29 is pressed against the second annular end portion 40 so as to thereby effect a first seal and the jockey 16 is pressed against the second annular seal 54 so as to thereby effect a second seal. Since two seals are provided, an excellent barrier to egress of water from the water main 60 to the water outlet 46 is provided

When it is desired to extract water from the water main 60 through the hydrant 56, a water feed pipe such as the water feed pipe 58 shown in Figure 3 is connected to the water outlet 46 of the hydrant valve 10 at the hydrant BIC connection 68 The control spindle 70 of the water feed pipe 58 is then manually rotated about its longitudinal axis using the handle 72 The control spindle 70 may be provided with an externally screw threaded portion which engages with a corresponding internally screw threaded portion on the water feed pipe 58, so that as the control spindle 70 is rotated, the nipple 74 of the control spindle 70 is caused to move downwardly and engage with the second engagement recess 32 in the jockey 16 Further rotation of the control spindle 70 effects movement of the jockey 16 downwardly of the guiding cage 18 As a result, the first and second seals are broken and water is forced under pressure from the water main 60 through the hydrant valve 10 and into the water feed pipe 58 If the pressure in the water feed pipe 58 rises above the pressure in the water main 60, water will tend to move in the opposite direction, that is from the water feed pipe 58 to the hydrant valve 10 and towards the water main 60 In this situation, the jockey 16 will move downwardly under pressure from the water feed pipe 58 and under force of gravity to the position shown in Figure 4b The direction of the force exerted on the jockey 16 is shown by the arrow in Figure 4b In this position, the first Annular seal 28 presses against the first annular end portion 38 so as to thereby effect a first seal and the jockey 16 presses against the first annular sealing ring 52 so as to thereby effect a second seal Further increased downward pressure on the jockey 16 causes the first Annular seal 28 and the jockey 16 to press harder against the first annular portion 38 and the first annular sealing ring 52 respectively so as to thereby enhance the strength of the first and second seals Since two seals are provided, an excellent barrier to backflow of water from the water feed pipe 58 to the water inlet 44 is provided

It will be appreciated that the hydrant valve may include only one of the first and second sealing means and that the first and second sealing means are interchangeable For example, the first and second Annular seals 28, 29 may be disposed on the first and second annular end portions 38, 40 instead of on the jockey 16

It will be appreciated that the guiding cage 18 and the channels of the jockey 16 ensure that the jockey 16 moves predictably relative to the water inlet 44 and the water outlet 46 and locates in the most desirable location relative to the first and second annular end portion 38, 40 and the first and second annular sealing rings 52, 54 to effect the most efficient seal when the jockey locates either in the first position as shown in Figure 4a or in the second position as shown in Figure 4b. It will also be appreciated that while the shape of the jockey 16 of the present example may have desirable aerodynamic characteristics, other shaped jockeys are also envisaged, the important aspect being that sealing means are provided between the jockey and the water inlet and between the jockey and the water outlet. It will also be appreciated that the hydrant valve may be formed of any suitable materials, including plastics or metal, which are substantially resistant to corrosion in use.

It will also be appreciated that the hydrant valve is configured so as to be substantially symmetrical about a central transverse plane. This enables the hydrant valve to be fitted to a hydrant with relative ease. Modifications and variations such as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims

1 A hydrant valve characterised in that it comprises a hollow body portion having a water inlet and a water outlet, the body portion defining a cavity and a sealing member being disposed in the cavity, wherein the sealing member is moveable between the water inlet and the water outlet, the sealing member is arranged to engage sealingly with the water inlet or the water outlet when the sealing member is located adjacent the water inlet or the water outlet respectively, the sealing member, under normal operating conditions when the hydrant is not required for use, is urged by water pressure into sealing engagement with the water outlet, mechanical means is provided for disengaging the sealing member from the water outlet when the hydrant is required for use, and the sealing member, under conditions of use where water pressure at a feed pipe exceeds water pressure a water main, is urged into sealing engagement with the water inlet

2 A hydrant valve according to Claim 1, characterised in that guiding means is provided adjacent the periphery of the sealing member for guiding the sealing member between the water inlet and the water outlet

3 A hydrant valve according to Claim 1 or 2, characterised in that the means for disengaging the sealing member comprises an actuating means extending away from the hollow body portion adjacent the water means 4 A hydrant valve according to Claim 3, characterised in that the actuating means is a rotatable control spindle

5 A hydrant valve according to any one of the preceding claims, characterised in that an annular seal is provided between the sealing member and the water inlet to provide an additional seal when the sealing member is located in the water inlet.

6 A hydrant valve according to any one of the preceding claims, characterised in that an annular seal is provided between the sealing member and the water outlet to provide an additional seal when the sealing member is located in the water outlet.

7 A hydrant valve according to any one of the preceding claims, characterised in that the water inlet includes an annular member disposed around the circumference of the water inlet

8 A hydrant valve according to any one of the preceding claims, characterised in that the water outlet includes an annular member disposed around the circumference of the water outlet

9 A hydrant valve according to any of the preceding claims, characterised in that the sealing member is predominantly ellipsoidal in shape