GB2166210A

GB2166210A - Branch connections to pipes

Info

Publication number: GB2166210A
Application number: GB08526224A
Authority: GB
Inventors: Eric Taylor; Robert Anthony Johnson; Alan Frederick Redpath
Original assignee: Bryan Donkin Co Ltd
Current assignee: Bryan Donkin Co Ltd
Priority date: 1984-10-25
Filing date: 1985-10-24
Publication date: 1986-04-30
Also published as: GB8426970D0; GB8526224D0

Abstract

A service connection adapted to be fitted to a gas mains or pipe, whereby a branch pipe can be secured in communication with the gas mains through the intermediary of the service connection for the purpose, for example, of providing a gas supply from the gas mains to a domestic premises, comprises a tubular body providing a gas flow passage therethrough, the tubular body being adapted at one end to be inserted into a tapped hole in the gas mains and at another end to receive a branch or service pipe. A valve is disposed between the ends of and within the flow passage to control opening and closing of the latter, and a fluid-tight seal arrangement is provided at said one end of the tubular body to provide a positive fluid-tight seal between the service connection and the gas mains. <IMAGE>

Description

SPECIFICATION A Service Connection This invention relates to a service connection adapted to be fitted to a gas mains or pipe whereby a branch pipe can be secured in communication with the gas mains through the intermediary of the service connection for the purpose, for example, of providing a gas supply from the gas mains to a domestic premises.

At present, a drilling and tapping machine is employed to tap holes in a gas mains at predetermined locations, service connections then being inserted into the tapped holes.

Such machines, interalia, must be capable of fitting service connections, such as service tees and nipples for example, up to limiting dimensions set by British Gas Standards laid down from time to time by the British Gas Corporation.

These service connections may be plugged until required for use, the service connections then being accessed, unplugged and a branch or service pipe suitably secured thereto.

It is an object of the present invention to provide an improved service connection adapted for securement to a gas mains and conforming to the aforesaid limiting dimensions while providing a simple controllable communication path between the gas mains and a branch or service pipe when required.

According to the present invention there is provided a service connection for a gas mains comprising a tubular body providing a gas flow passage therethrough, the tubular body being adapted at one end to be inserted into the tapped hole in the gas mains and at another end to receive a branch or service pipe, and the service connection being characterised in that a valve is disposed between the ends of and within the flow passage to control opening and closing of the latter, and in that a fluid-tight seal arrangement is provided at said one end of the tubular body to provide a positive fluid-tight seal between the service connection and the gas mains.

Preferably, the valve is a full-bore ball valve.

Preferably, an actuator is connected to the ball valve to permit manual operation of the latter.

Preferably, a sealing member, for example a gasket is provided between the actuator and tubular body.

An indicator is preferably provided on the actuator to indicate the condition of the ball valve, i.e. open, closed, or intermediate position.

An example of a suitable fluid-tight seal arrangement is disclosed in British Patent Specification No. 956591 and comprises a resilient sealing gasket adapted circumferentially to engage both the tubular body and the gas mains, a lock nut screw-engaging the tubular body and a pressure collar intermediate the sealing gasket and the lock nut, actuation of the latter urging the pressure collar against the sealing gasket to cause the latter to make a positive fluid-tight seal between the tubular body and the gas main.

It will, of course, be manifest that alternative forms of fluid-tight seal arrangements may be employed.

An embodiment of the present invention will now be described, by way of example, with reference to the single figure of the accompanying drawing which is a sectional view of a service connection according to the present invention.

The service connection is dimensioned within the limiting dimensions set by the British Gas Corporation for such connections.

It comprises a tubular body 10 internally screw threaded at one end as indicated at 11 for receiving a branch or service pipe (not shown) leading to, for example, a domestic premises.

The tubular body 10 at its other end comprises a large-diameter bore 12 within which is screwconnected as indicated at 13 a large diameter end 14 of a tubular connector 15. Relative rotation between the latter and the tubular body 10 is prevented by a lock screw 16.

The tubular connector 15 has a smaller diameter length 17 which is externally screw-threaded as indicated at 18.

The tubular body 10 and the tubular connector 15 define a rectilinear gas flow passage 19.

Within the tubular body 10 there is disposed a ball valve arrangement comprising a full-bore ball 20 rotatable between valve seats 21 and 22. The valve seat 21 engages a shoulder 23 of the tubular body 10, an O-ring seal 24 being located between the shoulder 23 and the valve seat 21.

The valve seat 22 is clamped in the tubular body 10 between the ball 20 and the large-diameter end 14 of the tubular connector 15. An O-ring seal 25 is located between the latter and the valve seat 22.

The tubular body 10 has a lateral tubular extension 26 through which extends an operating spindle 27 which is engaged with the ball 20.

The tubular extension 26 is closed by a clamp plate 28 bolted in position as indicated at 29. A sealing gasket 30 is secured between the clamp plate 28 and the end of the lateral extension 26.

An O-ring seal 31 is held in an annular recess in the operating spindle 27 and engages with the inner wall surface of the tubular extension 26.

An actuator cap or cover 32 is secured to the operating spindle 27 and at its rim 33 bears on the sealing gasket 30.

The cap or cover 32 is provided with an indicator 34 whereby an operator is able to see the condition of the ball 20, i.e. open, closed or intermediate position.

The cap or cover 32 bears on a disc spring or washer 35 which with friction plates 36 ensures that the ball 20 can only be positively operated, i.e.

operator (workman) controlled-it cannot inadvertently open or close.

To the exterior of the tubular connector length 17 is fitted a fluid-tight sealing arrangement comprising a resilient gasket 37, a lock nut 38 which screw-engages threading 18 and, between the gasket 37 and the lock nut 38 a pressure collar 39.

When a hole is tapped in a gas main 40 by a drilling or tapping machine in the usual way, the abovedescribed service connection with the ball 20 closed is screwed into the hole for the required length 17 of the tubular connector 15. The fluid-tight sealing arrangement is then adjusted to seal between the tubular connector 15 and the gas main 40 and is locked in position by the lock nut 38.

Thus there is provided a valve-controlled service connection ready for use when required simply by connecting a branch or service pipe thereto and opening the ball 20.

Claims

1. A service connection for a gas mains comprising a tubular body providing a gas flow passage therethrough, the tubular body being adapted at one end to be inserted into a tapped hole in the gas mains and at another end to receive a branch or service pipe, and the service connection being characterised in that a valve is disposed between the ends of and within the flow passage to control opening and closing of the latter, and in that a fluid-tight seal arrangement is provided at said one end of the tubular body to provide a positive fluid-tight seal between the service connection and the gas mains.

2. A service connection as claimed in Claim 1, in which the valve is a full-bore valve.

3. A service connection as claimed in Claim 2, in which an actuator is connected to the ball valve to permit manual operation of the latter.

4. A service connection as claimed in Claim 3, in which a sealing member, for example a gasket is provided between the actuator and tubular body.

5. A service connection as claimed in Claim 3 or 4, in which an indicator is provided on the actuator to indicate the condition of the ball valve, i.e. open, closed, or intermediate position.

6. A service connection as claimed in any one of Claims 1 to 5, in which the fluid-tight seal arrangement comprises a resilient sealing gasket adapted circumferentially to engage both the tubular body and the gas mains, a lock nut screwengaging the tubular body and a pressure collar intermediate the sealing gasket and the lock nut, actuation of the latter urging the pressure collar against the sealing gasket to cause the latter to make a positive fluid-tight seal between the tubular body and the gas mains.

7; A service connection for a gas mains, substantially as hereinbefore described with reference to the accompanying drawing.