WO1990014536A1

WO1990014536A1 - Valve for connection to a pressurized water main

Info

Publication number: WO1990014536A1
Application number: PCT/AU1990/000212
Authority: WO
Inventors: Earl Erling; John Richard Bugh
Original assignee: Industrial Pipe Systems Pty. Limited
Priority date: 1989-05-24
Filing date: 1990-05-22
Publication date: 1990-11-29
Also published as: GR900100398A

Abstract

A valve (3) adapted for connection to a pressurized main (2) comprising a valve chamber having an inlet port (21) and an outlet port (22) and a closure mechanism controlling the flow of fluid from the inlet to the outlet. The closure (35) may be of a pendulous construction swing mounted within the chamber so as to be movable in an arcuate path towards or away from a closed position wherein the closure seats with the inlet port (21). In a prefered embodiment the closure is movable between an operating position where it controls the flow of fluid to the inlet (21) and a displaced position whereat passage for tapping means is provided from the outlet port to the inlet port.

Description

TITLE: VALVE FOR CONNECTION TO A PRESSURIZED WATERMAIN

TECHNICAL FIELD

This invention relates to a method of, and apparatus for, connecting a mains valve or cock to a main, and more particularly to a pressurized water main.

BACKGROUND ART

Water main pipes have hitherto been manufactured predominantly from metal. When connections to a main were made, it was necessary to close off the main or freeze the water on either side of a junction point to enable the main to be tapped and a service pipe to be joined with the main. It is usual practice to provide a mains cock on the service pipe adjacent the main. The mains cock is required to have a non-return valve (or "jumper") to prevent contamination of water in the main pipe in the event that pressure in the main falls below that in the service pipe.

Various methods have been proposed whereby a conventional mains cock can be connected ("hot tapped") to a main pipe while the latter remains pressurized. The method currently employed involves use of an apparatus which seals with the exterior of the main and provides a chamber which encloses a volume bordering the main pipe. This apparatus permits the main to be tapped in a first operation, and then to be fitted with a mains cock in a second operation, both the tapping drill and the main being contained within the apparatus. The apparatus is of substantial size and weight. The time required to make a hot tap connection by such means is of 30 minutes or more.

Some water supply authorities are now using plastics pipes but use conventional metal fittings and traditional methods of joining and tapping as were used with metal pipes. The use of metal fittings with plastics pipes is undesirable in view of the different rates of expansion of the differing materials and the difficulty of sealing one with the other.

When using metal pipes, it is required by the authorities that the devices installed should electrically insulate the watermains at the private service connection.

An object of the present invention is to provide a improved method of, and fittings for, connection of a mains cock and service line to a main pipe which avoid or at least ameliorate some of the above discussed disadvantages of prior art.

That is achieved in preferred embodiments of the present invention by means of fittings manufactured predominantly from plastics mouldings. A mains cock is provided which includes a non-return valve, which may be saddle mounted to the pressurized main, and which permits the main to be subsequently tapped through the cock whereby to place the cock in operative communication with the main.

DISCLOSURE OF INVENTION

According to one aspect, the invention consists in a valve adapted for connection to a pressurized main comprising a valve chamber having an inlet port in alignment with an outlet port and a closure mechanism, the closure mechanism being movable between an operating position whereat the closure mechanism controls the flow of a fluid from the inlet to the, or another, outlet and a displaced position whereat passage for tapping means is provided from the outlet port to the inlet port.

For preference in the operating position the closure mechanism is biased towards a position in which it seals with a seating of the inlet port. For preference also the outlet port from which fluid may exit is the outlet through which a tapping means may be admitted to extend through the inlet port.

In another embodiment of the invention, a mains cock is provided which includes a non return valve, for connection to a pressurized or non pressurized mains, either as a replacement to an existing unit or as an original unit tapped to the mains by any suitable means.

According to a second aspect, the invention consists in a valve comprising a valve chamber having an inlet port and an outlet port, a closure swing-mounted within the chamber and adapted to move in an arcuate path towards or away from a closed position in which the closure seats with the inlet port, and a cam mechanism within the chamber operable to drive the closure towards the seat.

In preferred embodiments the inlet port defines a port axis and the closure is hinge or swing-mounted at an axis spaced from and transverse to the port axis. Preferably the closure is resiliently biased towards the closed position, desirably by means of an integrally moulded leaf spring.

The cam mechanism may be a cylindrical cam which bears against a rear face of the closure, when the front face of the closure is seated, the cam being releasable by axial rotation from outside the body.

In preferred embodiments of the invention the closure is also mounted for translation from the port axis whereby unobstructed access from the outlet port to the inlet port may be given to a drill, cutter or other hot tapping mechanism.

Various embodiments of this invention will now be described by way of example only with reference to the accompanying drawings in which figures 1 to 4 refer to a first embodiment, figures 5 to 9 refer to a second embodiment, figures 10 to 13 refer to a third embodiment and figure 14 refers to a fourth embodiment. BRIEF DESCRIPTION OF DRAWINGS

Figure 1 shows a sectional elevation of the assembly of the watermain, saddle, first embodiment of the cock and drilling attachment (with cock in closed position) ,

Figure 2 shows a sectional side elevation of the cock (in closed position) of figure 1,

Figure 3 shows a sectional plan view corresponding to Figure 2,

Figure 4 shows a sectional elevation of assembly as for figure 1, with cock in open position with drill in position for operation.

Figure 5 shows a sectional elevation of the assembly of a water main and a second embodiment of the cock (with cock in the open position).

Figure 6 shows a sectional elevation of the cock as shown in Figure 5 (with cock in the closed position) ,

Figure 7 shows a sectional end elevation of the cock along the line 7-7 of Figure 6,

Figure 8 shows a sectional end elevation of the cock along the line 8-8 of Figure 6,

Figure 9 shows a sectional plan view of the cock along the line 9-9 of Figure 6.

Figure 10 shows a sectional elevation of the assembly of a watermain and a third embodiment of the cock (with cock in the open position) .

Figure 11 shows a sectional part view of the connection of the cock to the watermain referred to in Figure 10, shown in the position prior to connection.

Figure 12 is a sectional part view of the connection shown in Figure 11 shown in the first stage of connection.

Figure 13 is a sectional part view of the connection shown in Figure 11 shown in the fully connected stage.

Figure 14 shows a part view of an alternative means of connection to the watermain.

BEST MODES FOR CARRYING OUT THE INVENTION

Referring to figure 1 there is shown an assembly comprising a pipe saddle 1 clamped to a live water main 2 and coupled to a cock indicated generally at 3. A drilling attachment 4 is also coupled to cock 3.

Saddle 1 is conventional and comprises a split cylindrical collar consisting of a first collar portion 11 and a second collar portion 12. Each collar portion is flanked by flanges 13 extending laterally and longitudinally. The collars are held in clamping engagement about the circumference of pipe 2 by means of bolts 14 extending through bosses defined in flanges 13 and provided with nuts 15 (not shown) .

Collar 12 forms a 'T' junction with a cylindrical side arm 16 extending substantially at right angles to the axis of pipe 2 and terminates at a bush 17 which is internally threaded at 18, bush 17 being sealed at its interface 19 with side arm 16.

Referring now also to figure 2 and figure 3 there is shown the water cock 3 consisting of a main body 20 having two in-line horizontally opposed ports 21 and 22. Port 21 communicates with the interior of body 20 at a valve seat 23 and connects with the interior of side arm 16 via a spigot 24 which is externally threaded for engagement with bush 17 and held thereto by a locking nut 25. A flange 26 is provided being integral to body 20 having a standard distance across the flats 27 to assist installation and removal of cock 3.

A cylindrical side wall 28 of body 20 extends perpendicularly from the axis of ports 21 and 22.

An inner sleeve 29 is slidably and telescopically engaged with side wall 28, a seal being effected between side wall 28 and sleeve 29 by means of an '0' ring (not shown) mounted on sleeve 29 in first ring groove 31.

Forming a central webb 32 to inner sleeve 29 is a moulding comprising a spindle boss 33 and a ball socket 34. A pendulous closure device 35 is snap mounted to socket 34 and comprises a ball pivot 36, connected to a stem 37 terminating in a cylindrical valve 38 having a front valve face 39 and having a rear valve face 40. A leaf spring 41 integral with stem 37 extends towards and bears against adjacent web 32.

With the cock in the closed position as shown in Figures 1, 2 and 3, the bevelled edge of valve seat 23 seats in planar contact with a bevelled edge of valve face 39.

Spindle 42 extends through boss 33 to the body interior terminating in a second spigot 43, coaxial with spindle 42, and locating in retaining boss 44 integrally formed in main body 20. A shoulder 45 is formed on spindle 42 which provides a bearing surface 46 adjacent the interior extremity of spindle boss 33. A cam 47 extends from spindle shoulder 45 to second spigot 43, the cam being eccentric with respect to the spindle axis and acting in a crank like arrangement bearing against rear face 40 of closure 35.

A seal is effected between the shoulder 45 and inner sleeve 29 by an 'O' ring (not shown) located in a corresponding second ring groove 49 in spindle boss 33.

Spindle 42 is retained within spindle boss 33 by means of a gland nut 50 having an internal thread 51 in engagement with an external thread portion 52 of spindle 42.

A seal is effected between the gland nut 50 and spindle boss 33 by means of an '0' ring (not shown) located in a third ring groove 54 on the gland nut 50. Gland nut 50 is limited in travel by an internal shoulder 55 corresponding to an external shoulder 56 on spindle 42. Spindle 42 is provided at its external extremity with a threaded portion which is secured to a handle 57 by a nut 58.

An annular cap 59 is engaged to an external thread 60 forming the peripheral surface of the cylindrical sidewall 28 via an internal thread 61, the lip 62 of the cap 59 retaining said inner sleeve 29.

A fourth *0' ring (not shown) located in a fourth ring groove 64 is located on lip 62 to effect a seal between cap 59 and inner sleeve 29.

As shown in Figure 1; cock 3 is also in engagement with a drilling attachment 4 comprising a cylindrical drilling guide 65 forming at one end a peripherally tapered third spigot having a male taper 66 extending from an integral collar 67.

Male taper 66 is in planar contact with a corresponding female taper 71 in fourth spigot 68 of cock 3, extending from port 22 being restrained by means of a collar 69 having lip 70 in abutment with the integral collar 67 of drill guide 65. Spigot 68 is engaged with collar 69 by means of corresponding threads 72.

Centrally located along length of guide 65 is an integral internal bearing 73. Slideably contained within guide 65 is a drill 74 comprising at one end located nearest said mains 2 a hollow cylindrical cutter 75 having at one end sharp blade edge 71A. Cutter 75 is detachably mounted on a fifth threaded spigot 76 forming part of a drill shaft 77 which is slidably engaged with bearing 73. A seal is effected between bush 73 and drill shaft 77 by means of a fifth '0' ring (not shown) and corresponding fifth ring groove 79.

Located towards the driven end of drill 74 is an externally threaded collar portion 80 which engages with the internally threaded end of drill guide 65. Conventional flats are provided at the driven end of the drill for connection of an appropriate turning device.

In operation, this embodiment of the invention may be used as follows.

1. Pipe saddle 1 is clamped to the live mains 2 and secured with bolts 14 as shown in Figure 1.

A seal between the saddle 1 and mains 2 achieved, for example, by welding or application of an adhesive.

2. Water cock 3 in the closed position as shown is then coupled to the saddle 1 and secured with the lock nut 25.

3. Drilling attachment 4 is coupled to the second port 22 of the cock 3 and is retained by collar 69.

4. The annular cap 59 is then unscrewed until it contacts said handle 57.

5. Cam 47 is swung away from the closure device 38 by turning handle 57 180° about the axis of the spindle 42. This releases the closure device which will remain in position by means only of the leaf spring 41.

6. Handle 57 is then pulled axially away from the axis of the ports thereby withdrawing the inner sleeve 29, cam 47, and web 32 complete with closure device 38, providing an unobstructed passage between the ports 21 and 22 (as shown in figure 4). The interior of body 20 remains sealed from the exterior by virtue of 'O' rings (not shown) seated in grooves 31 and 49.

7. Drill 74 can then be pushed longitudinally through ports 22 and 21 of the cock until the threaded collar portion 80 engages with the internally threaded end of the drill guide 65. At this point tip of cylindrical cutter 75 will be in close proximity with the wall of the live mains 2.

8. Rotating drill 74 by attachment of a suitable lever to the end 81, rotation about the threaded portion 80 will drive cutter 75 progressively into mains pipe 2. A small circular section of pipe will be removed and retained within cutter 75.

9. When the cutting action is complete drill 74 is withdrawn to its original position with cutter 75 in abutment with the internal bush 73. Water from the pressurized mains will fill the cock; a seal being effected by the '0' ring (not shown) located between bush 73 and drill shaft 77.

10. Annular cap 59 is then fully screwed towards the axis of the ports, displacing water and lowering the closure device 38. Valve face 39 slides on body surface 82 water pressure acting against spring 41 to push the valve face inwardly of body 20. When this step is completed spindle spigot 43 is seated in boss 44. Cam 47 is then rotated through 180° bearing on rear face 38F of the closure and driving the closure device in an arcuate path against valve seat 23 thereby sealing the first port 21.

11. The drilling attachment 6 can then be removed and the cock 3 coupled to a service line as required. Cam 47 may be released as required to permit or prevent flow from the pressurized main 2 to the service line.

In the event of back pressure from the service line, the closure device, assisted by the spring, will close immediately thereby prevent mains contamination.

Valve seat 23 may be made of brass or gun metal and desirably extends to the free end of spigot 24 to provide mechanical support for the tapered threaded exterior of spigot 24.

An advantage of manufacturing the body of the valve from plastic is that corrosion by virtue of DC currents as occurs with metal pipes can be avoided.

An additional advantage of the preferred embodiment is that the two outermost seals 63 and 53 can be replaced in situ without disconnecting the service line.

As will be apparent to those skilled in the art from the teaching hereof the invention may be embodied in other forms. For example, valve body 20 may be provided with additional ports. The drill shank need not be threaded and may be driven by other means and cutters of different form may be employed. The cam need not be cylindrical and could take other forms. Coupling methods may be varied.

Although a pendulous valve closure is highly preferred, in other embodiments the valve closure could be adapted for axial movement towards or away from a port for example by being captured in a guide, the guide being moveable to provide passage for a cutter from one port to the other.

Such embodiments and variants are deemed to be within the scope of the invention herein disclosed.

A second embodiment of this invention will now be described by way of example only with reference to figures 5 to 9.

Referring to Figure 5 there is shown an assembly comprising a water main 1 coupled to a cock indicated generally at 2.

The water main shown is of metal construction, this example of the cock having metal inserts appropriate for connection.

The water cock consists of a main body 3 having an inlet port 4 and outlet port 5. Port 4 communicates with the interior of body 3 at a valve seat 6 and connects with the water main 1 via a spigot 7 which is externally threaded for engagement with the water main 1 and held thereto by a locking nut 8. A rubber grommet 9 is positioned between lock nut 8 and water main 1 to effect a water tight sealing engagement.

A flange 10 is provided being integral to body 3 having a standard distance across the flats 11 to assist installation and removal of cock 2.

Referring now to Figures 5 to 9 inclusive, there is shown an inner cap 12 disposed within the upper portion of body 3 in a plane parallel to, and spaced away from the plane of the axes of ports 4 and 5. A pendulous closure device 13 is snap mounted to a socket 14 and comprises a rod pivot 15, connected to a stem 16 terminating in a substantially conical valve 17 having a front valve face 18 and a rear valve face 19. A leaf spring 20 integral with stem 16 extends towards and bears against the innermost surface of inner cap 12.

With the cock in the closed position as shown in Figures 6, 7, 8 and 9, the bevelled edge of the valve seat 6 seats in planar contact with a bevelled edge of valve face 18. A spindle 21 is fixed to a ferrule 22 located with an extending portion of body 3 such that its axis is parallel to and displaced from the axis of spigot 7 and inlet port 4. The ferrule is rotatably constrained within body 3 by a retaining cap 23 fixed to the body by means of adhesive or welding.

A helical cam 24 extends from the spindle 21 and ferrule 22 assembly, being an integral part of the ferrule 22. Cam 24 is substantially cylindrical along its axis extending approximately 270° peripherally, defining a "low" point 25 adjacent the ferrule and axially advancing in a helical configuration towards a "high" point 26 at the centre of the body 3.

A seal is effected between the ferrule 22 and body 3 during rotation of the cam assembly by means of 'O' rings (not shown) seated in ring grooves 27. Similarly, a seal is affected between the inner cap 12 and body 3 by means of an '0' ring (not shown) seated in ring groove 28. The inner cap is retained within body 3 by an internally threaded outer cap 29 which engages a corresponding thread on the outer surface of body 3 and a seal effected between the cap 29 and body 3 by a further '0' ring (not shown) seated in ring groove 30. The outer cap is fixed with adhesive.

A further spigot 31 extends outwardly along the central axis of outlet port 5. In this embodiment the spigot 31 has a metal insert 32 for connection to a range of standard fittings.

In operation, this embodiment of the invention may be used as follows.

1. In the case of installation as a replacement unit to the existing metal cocks, the old unit, having a tapered threaded spigot for connection to the pipe, is removed.

2. The tapered thread portion of the mains 1 is drilled out and re-tapped to a parallel thread corresponding to that of the spigot 7 of the cock 2.

3. The spigot 7 of cock 2 is then engaged with the thread portion of the main 1 with a rubber grommet or other sealing means fixed around the spigot and main 1 against which the locking nut 8 is secured.

4. The cock is installed in the closed position as shown in Figure 6, with the 'high' point of the cam urging and securing the closure device 13 against the valve seat 6 thereby sealing the inlet port 4.

5. The service line is then coupled to the spigot 31 adjacent the outlet port 5 by means of any of the standard fittings and couplings available.

6. When the service line is secured, the spindle can be rotated 270° such that the closure follows the cam face. A limiting tab 33 is provided integral to body 3 at the base of the inlet to the spigot housing the cam assembly. This corresponds to an annular groove at the inner edge of the ferrule such that the rotational travel of the cam is limited to prevent the closure running off the cam face.

7. After full rotation of the cam (within the tab limits) the closure device is in contact with the 'low' point, being urged against the cam 24 by the mains water pressure. At this point the inlet port 4 is unobstructed and the pressurized mains water enters the service line freely.

8. In the event of back pressure from the service line, the closure device, assisted by the spring, will close immediately thereby preventing mains contamination. An additional advantage of this embodiment is that it can be coupled to both a metallic service and mains line and will serve to electrically insulate the mains from the service line.

As will be apparent to those skilled in the art from the teaching hereof, the invention may be embodied in other forms.

For example, the swing mounted closure and spring mechanism may be formed from two or more integrally hinged sections so as to act as a toggle.

In another form the spring can be arranged so as to bias the closure to both an open or closed position, by connecting the spring to a point in line with, but displaced from, the closure pivot. Such embodiments are deemed to be within the scope of the invention.

A third embodiment of this invention will now be described by ay of example only with reference to Figures 10 and 11.

This embodiment is very similar to the second embodiment shown in Figures 5 to 9 and corresponding numerals will be used to denote corresponding features. The major differences lie in the changes made to the area of body 3 supporting the inner cap 12 and the means of connection of the cock 2 to the watermain 1.

In order to reduce the overall width of the cock so as to facilitate its connection to the mains using existing tapping equipment, the inner cap 12 is ultrasonically welded to main body 3. By eliminating the threaded portions the width is reduced and an outer cap is no longer required.

With watermains in particular, it is considered desirable to move away from pipe sealants, hemp sealing or teflon tape because not only are they often difficult to apply due to the tapping box employed in the tapping operation, but because they tend to contaminate the water. A preferred alternative connection means is illustrated in Figures 10 to 13.

Figure 11 shows the connector prior to use. The connector includes a brass spigot 7 having a first tapered portion 82 and a second reversed tapered portion 83 from which a threaded section 84 extends. Connected to this spigot (prior to the moulding of body 3) is a gun metal lock nut 8 having an integral sleeve 85 externally threaded and connected to the nut 8 by a thin necked portion 86.

Prior to connection with the mains 1, the nut and sleeve assembly is rotated such that it abuts the main body 3 of the cock as shown in Figure 11. The cock 2 is then held to prevent its rotation and the lock nut assembly is rotated by means of a suitable device. The threaded sleeve 85 will then engage the corresponding thread provided in mains 1 until it is fully secured as shown in Figure 12. At this point further rotation of the nut 8 causes it to shear from the sleeve 85.

Continuous rotation of the now independent nut 8 will then cause the spigot 7 to move away from mains. This in turn causes the reverse tapered portion 83 to contact the sleeve and drive it radially outwards into sealing engagement with the mains pipe 1, thereby eliminating the need for extraneous sealing materials. It may however be advantageous to powder coat the sleeve with a suitable plastic or use PTFE tape in the usual manner.

Referring finally to Figure 14 there is shown another alternative means of connecting the cock 2 to the mains 1.

A threaded sleeve 87 is partially screwed into the mains pipe 1 as shown in the drawing. The spigot 7 of cock 2 is then inserted into the sleeve 87 until the lock nut 8 engages with the expossed portion of the external thread on the sleeve. Rotation of nut 8 then forces the male taper 88 of spigot 7 to engage a corresponding female taper 89 provided in sleeve 87. The spigot is driven down by action of lip 90 on nut 8 against a shoulder 91 provided on sleeve 87.

Although the invention has been described with reference to a number of examples, it will be apparent to those skilled in the art that the invention may be embodied in many other forms.

Claims

1. A valve comprising a valve chamber having an inlet port and an outlet port, a closure swing-mounted within the chamber and adapted to move in an arcuate path towards or away from a closed position in which the closure seats with the inlet port, and a cam mechanism within the chamber operable to drive the closure towards the seat.

2. A valve according to claim 1 wherein the inlet port defines a port axis and the closure is hinge or swing-mounted at an axis spaced from and transverse to said port axis.

3. A valve according to claim 2 wherein the closure is snap mounted to a part of said valve.

4. A valve according to any one of the preceding claims wherein the closure is resiliently biased towards the closed position.

5. A valve according to any one of the preceding claims wherein the closure is mounted for translation from the port axis whereby unobstructed access from the outlet port to the inlet port may be given to a hot tapping mechanism.

6. A valve adapted for connection to a pressurized main comprising a valve chamber having an inlet port in alignment with an outlet port and a closure mechanism, the closure mechanism being movable between an operating position whereat the closure mechanism controls the flow of the fluid from the inlet to the, or another, outlet and a displaced position whereat passage for tapping means is provided from the outlet port to the inlet port.

7. A valve according to claim 6 wherein the closure is adapted to move toward or away from a closed position in which the closure seats with the inlet port.

8. A valve according to claim 7 including a cam mechanism within the chamber operable to drive the closure toward the seat.

9. A valve according to anyone of claims 6 to claim 8 wherein in the operating position the closure mechanism is biased towards a position in which it seals with a seating of the inlet port.

10. A valve according to claim 9 wherein the outlet port from which fluid may exit is the inlet through which a tapping means may be admitted to extend through the inlet port.

11. A valve according to anyone of claims 4, 5, 7, 8, 9 and 10 wherein the closure is resiliently biased by means of an integrally moulded leaf spring.

12. A valve according to anyone of claims 1 to claim 5 wherein the cam mechanism is in the form of a cylindrical cam which bears against a rear face of the closure when the face of the closure is seated, the cam being releasable by axial rotation from outside the body.

13. A valve according to anyone of claims 8 to claim 11 wherein the cam mechanism is in the form of a cylindrical cam which bears against a rear face of the closure when the face of the closure is seated, the cam being releasable by axial rotation from outside the body.

14. A valve according to claim 12 or claim 13 wherein the cam mechanism is substantially in the form of a crank, the longitudinal axis thereof being disposed perpendicular to said port axis.

15. A valve according to claim 12 or claim 13 wherein the cam is substantially in the form of a helix operable in line with said port axis.

16. A valve substantially as herein described with reference to the accompanying drawings.