GB2472886A

GB2472886A - A device for stopping and controlling flow in a pressurized tube or pipe

Info

Publication number: GB2472886A
Application number: GB1008614A
Authority: GB
Inventors: Simon Senior Clifford
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-05-25
Filing date: 2010-05-25
Publication date: 2011-02-23
Anticipated expiration: 2030-05-25
Also published as: GB2472886B; GB201008614D0

Abstract

A device for stopping and controlling flow in a pressurized tube or pipe that clamps around a tube or pipe containing fluid or gas under pressure, sealing the area to be cut. Operation of a screw mechanism allows the slicing of a complete section of tube or pipe within the sealed area. The sliced tube or pipe is forced into a holding chamber as a single section without debris entering the contained flow, and remains there throughout the service life of the device. The cutter is locked in position with a stud that also acts as a pressure test facility as used prior to cutting to ensure a good water and gas tight seal. Further operation of the handle in either direction allows the continued operation of a valve to stop and vary flow. A similar device without the valve mechanism allows the tube or pipe to be cut and a branch line installed with full bore flow and without debris entering the contained medium.

Description

This invention relates to a device for cutting tube and pipe containing fluid or gas under pressure and the simultaneous installation of a flow stopping and controlling device within the tube / pipe, or a branch tee, all in a single screw down action.

Background

The installation of valves or branch lines in tube and pipe lines of 50mm and less requires either draining the contained medium, freezing if fluid, and the movement of existing fixed tube or pipe to allow fitting room. Equipment does exist for large scale pipe lines to allow hot tapping under pressure but require multistage cutting and valve insertion procedures and allow cutting debris to enter the system. These are mainly for large scale pipelines. This invention relates to a device that will allow the insertion of a valve or branch tee in the tube or pipe while under pressure, without the need to disturb tube or pipe and in a single screw down action. The result maintains full bore flow without cutting debris entering the flow of contained medium. This invention is more specific to small scale tube and pipe lines of 50mm diameter and less.

Statement of invention

This invention proposes a device that clamps around a tube or pipe that contains fluid or gas under pressure, sealing the area to be cut. Operation of a screw mechanism allows the slicing of a complete section of the tube or pipe within the sealed area. The sliced tube or pipe is forced into a holding pocket as a single section without further debris entering the contained flow and remains there throughout the service life of the device. The cutter is locked in position with a stud that also acts as a pressure test facility prior to cutting. Further operation of the handle in either direction allows the continued operation of a valve to stop and vary flow. A similar device without the valve mechanism allows the tube or pipe to be cut and a branch line installed with full bore flow and without debris entering the contained medium.

Advantages The use of this device allows the installation of new valves, replacement valves, full bore branch tees and repair kits in a single screw down action. This reduces time to drain systems, eliminates the need to move tube or pipe to gain fitting room and, can replace the commonly used freezing method without time constraints over how long a freeze facility will last. This device will allow full bore flow through the valve or branch tee. The cutting action manages debris so that no foreign bodies enter the contained medium.

Detailed description

The following description refers to drawings (fig 1 to 6) Fig 1 to fig 4 refer to a flow stopping and controlling device.

Fig 1 indicates the tube or pipe clamped prior to cutting.

Fig 2 indicates the tube cut with removed section of tube or pipe locked in the debris chamber with the cutter Fig 3 indicates the removal of the locking tab A to allow the sealing mechanism to be backed off without the cutter and cutting stem which will be locked in position after cutting.

Fig 4 indicates the side view of fig 3 showing the cutter lock and pressure tester N. It also shows the clamp bolts M that secure the clamp around the tube or pipe.

A tube clamp body J and complete mechanism as in fig 1 is clamped around a tube or pipe I and secured with the bolts as shown in fig 4. At this point, the uncut tube or pipe remains pressurised and with free flow.

The Cutter lock and pressure tester' N in fig 4 is used to verify a fluid and gas tight seal pre cutting within the cutting chamber as seen in fig 1.

A locking tab A is installed to allow the cutter H, cutting stem D and rising stem C to move at the same time. The valve mechanism C, E, F, G at this stage is carried with the cutter.

The cutter H is formed with a sharp profiled edge that slices the tube or pipe to allow a single section of tube or pipe to be removed without cutting debris.

Fig 2 shows the complete device after the tube or pipe section has been removed. The cutter lock and pressure tester' N as shown in fig 4 is used to lock the cutter H in place with the removed section of tube or pipe contained within and located in the debris chamber K. Removing the locking tab A allows the valve mechanism C, E, F, G to back off on turning the operating handle B while leaving the cutter H and cutting stem D stationary. This is shown in fig 3.

The device at this stage is ready for continued operation.

The device seal F rises and falls using a slip mechanism E, L. The rising stem C and slip stem E are secured together and not independent. As they move up and down, the valve seal F is allowed to rise and fall without rotation. The valve seal at the sealing area is a split tube which rises and falls in a groove on the valve body housing X. As the seal is moved to stop flow, the device seal lowers to the position as in fig 2 (locking tab A removed). Continued clockwise operation of the operating handle B allows the compression of an elastomeric material G within the device seal. This forces the walls of the outer seal F to expand to seal the flow around the cut ends of the tube or pipe.

Fig 5 and Fig 6 show the same cutter with out the valve mechanism to allow full bore flow through a branch tee. The rising stem 0 is fixed to the cutting stem P and cutter T. When the tube or pipe is clamped and pressure tested, the rising stem is screwed down removing a section of the tube or pipe. The cutter T containing the removed section of tube or pipe is locked in position with the combined cutter lock and pressure tester. Flow is now free to exit through the branch tee U.