GB2265199A

GB2265199A - Restricting fluid flow in a pipe

Info

Publication number: GB2265199A
Application number: GB9205100A
Authority: GB
Inventors: Robert Brian Warren
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-03-09
Filing date: 1992-03-09
Publication date: 1993-09-22
Also published as: GB9205100D0

Abstract

A method of restricting fluid flow in a pipe involves holding the pipe rigidly within a vice comprising a saddle 5 and an associated pair of interlocking jaws 1, 2. A power ram 22 is driven through the saddle 5 towards the pipe so that the surface of the pipe adjacent to the saddle 5 is forced towards the rear surface of the pipe abutting the jaws 1, 2. As a result the cross sectional area is substantially reduced and fluid flow in the pipe may be totally restricted. The jaws are preferably driven into and out of engagement by means of a pair of hydraulic rams 15, 16. When driven into engagement the jaws are held in position by means of a locking device such as a pin 14. The jaws and saddle may be equipped with cooling means. <IMAGE>

Description

METHOD AND APPARATUS FOR CONTROLLING FLUID FLOW.

This invention relates to a method of reducing fluid flow in pipes and apparatus therefor.

Fluids such as liquids, gases or mixtures thereof are frequently directed through pipes at high pressure and often at considerable rates of mass flow. The rate of flow is usually controlled by conveniently sited control valves located in the pipe run. It is possible through accident or deliberate acts for such pipes to be ruptured causing an escape of fluid with disastrous consequences.

Whenever possible such flow may be terminated by operation of one of the control valves however occasions arise when such valves are inaccessible or damaged.

In the case of oil wells crude oil containing dissolved gas rises at high pressure from the oil reservoir through a supply pipe lining the well bore and rising above the ground to a well head containing a control valve. In the event of the supply pipe being ruptured between the well head and the well bore there is no direct means of controlling the fluid flow. The crude oil then emerges as a jet of fluid having considerable kinetic energy. Due to the presence of low molecular weight hydrocarbons as liquids or dissolved gases there is considerable risk of fire, Any attempts to approach such jets, whether burning or not is extrememly hazardous.

The present invention provides a method of preventing or reducing fluid flow in pipes which may be used under hazardous conditions with low risk to the operators. The method may be performed using remotely operated equipment.

According to the present invention there is provided a method of restricting fluid flow in a pipe comprising holding the pipe rigidly within a vice comprising a saddle and an associated pair of interlocking jaws, driving a power ram through the saddle towards the pipe whereby the surface of the pipe adjacent to the saddle is forced towards the rear surface abutting the jaws until the cross sectional area is substantially reduced.

There is also provided a device comprising the combination of a vice and a ram which is particularly useful for controlling high pressure oil flows such as those emerging from damaged well heads. The upwardly emerging pipes from oil wells are of standard diameters so that a device designed to accomodate pipes having a standard size can be repeatedly used on a series of leaking or damaged pipes.

Preferably the inner dimensions of the jaws and saddle are proportioned to match the outer surface of the pipe with which the device is to be used. When the jaws are closed the inner surfaces form an enclosure which matches the outer surface of the associated pipe; this enclosure will generally be circular.

The head of the ram driven into the enclosure is preferably contoured to match the inner surfaces of the vice jaws when they are closed. In the case of a circular enclosure the surface of the ram will be cylindrical. Using such a contour and with the application of an appropriate amount of pressure any pipe within the enclosure will be crushed to a semi-circular sheet. In the preferred embodiments the upper and lower edges of the ram surface will be tapered to prevent undue stress on the edges of the crushed pipe which might cause it to rupture.

The power source for the ram can be produced in known manner from a hydraulic or other drive system. The saddle and jaws combination is preferably demountably attached to the power source so that a series of combinations designed to accomodate different sizes of pipe may by driven by a single source. The power source may be included in a vehicle or moveable mount operated from behind a shield giving physical protection from the emergent crude oil and also from the heat emitted if the flow has been ignited.

The jaws and saddle are prefereably made from steel castings which provide both strength and the necessary resistance to high temperatures. However other materials may be used in special applications such as titanium for air portable equipment where a compromise is necessary between weight and strength.

The jaws are preferably driven into and out of engagement by means of a pair of hydraulic rams as shown hereinafter.

When driven into engagement the jaws are preferably held in position by means of a locking device such as a pin.

In situations where fire is present water jets may be used to cool the jaws and saddle. High pressure water jets may be used to drive away sand, oil sludge and other- matter which could clog the device and cause malfunction.

In order that the invention may be clearly understood it will now be described with reference to the accompanying drawings in which: Figure 1 is a vertical view of a vice and ram used in the method of the invention, Figure 2 is a side view of the device shown in Figure 1, Figure 3 is an end view of the device shown in Figure 1, and Figure 4 is a series of schematic views of the vice and ram showing their mode of operation according to the invention.

The vice, see Figure 1, consists of a pair of jaws 1 and 2, pivotally attached by bearings 3 and 4 to a saddle 5. The pivots 3 and 4 allow the jaws 1 and 2 to move through arcs as indicated by the arrows. The inwardly facing surfaces 6 and 7 of the jaws together with the inward surface 8 of the saddle 5 forms a substantially circular enclosure 9.

The saddle 5 has a base portion 11 arranged to be mounted by bolts 12 on a vehicular or static support (not shown).

The jaws 1 and 2 are arranged to engage along the line 13 and be locked in together by a pin 14 when in engagement.

The jaws 1 and 2 are driven from their open position into engagement by hydraulic rams 15 and 16 acting between pivotal mounts 17 and 18 on the base 11 and mounts 19 and 21 on the jaws 1 and 2.

The saddle 5 has a cylindrical passage which allows a power ram 22 to be ~driven into and out of the enclosure 9 as indicated by the arrow. The ram 22 is driven by hydraulic power means (not shown) associated with the support to which the vice is attached. The front surface 23 of the ram 22 has a cylindrical contour which matches the inner surfaces 6 and 7 of the jaws 1 and 2 when they are closed.

The operation of the vice according to the invention is described with reference to schematic drawings, see Figures 4a 4b and 4c. The simplified vice shown consists of a pair of jaws 31 and 32 which are pivotally attached by bearings 33 and 34 to a saddle 35. The inwardly facing surfaces 36 and 37 of the jaws together with the inner surface 38 of the saddle 35 form a substantially circular enclosure when the jaws 31 and 32 are closed. The saddle 35 has a base portion 39 attached to a support (not shown).

The jaws 31 and 32 are arranged to be locked together by a pin 41 when in engagement. The saddle 35 has a cylindr ical passage which allows a power ram 42 to be driven into and out of the enclosure formed when the jaws 31 and 32 are closed. The front surface 43 of the ram 42 has a cylindrical contour which matches the inner surfaces 36 and 37 of the jaws 31 and 32 when they are closed. A circular pipe 44 is shown abutting the inner surface 38 of the saddle 35.

In operation, see Figure 4a, the jaws 31 and 32 are driven into engagement by hydraulic rams (not shown). When engaged, see Figure 4b, the jaws 31 and 32 are held in engagement by the locking pin 41 and enclose the pipe 43.

The power ram 42 is then driven into the saddle 35, as shown by the arrow, and enters the circular enclosure formed by the saddle and jaws which contains the pipe 43.

The pipe 43 is forced by the front surface 43 of the ram against the wall formed by the inner surfaces 36 and 37 of the closed jaws 31- and 32. The force causes the wall of the pipe 44 to collapse. Continued force applied to the ram 42 in the direction shown by the arrow, see Figure 4c, compresses the pipe 44 completely so that its internal diameter is reduced to zero and fluid flow through the pipe is prevented.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

Claims

1. A method of restricting fluid flow in a pipe comprising holding the pipe rigidly within a vice comprising a saddle and an associated pair of interlocking jaws, driving a power ram through the saddle towards the pipe whereby the surface of the pipe adjacent to the saddle is forced towards the rear surface abutting the jaws until the cross sectional area is substantially reduced.

2. The method of according to claim 1 wherein the inner dimensions of the jaws and saddle are proportioned to match the outer surface of the pipe with which the device is to be used.

3. The method of according to claim 1 or claim 2 wherein when the jaws are closed the inner surfaces form an enclosure which matches the outer surface of the associated pipe.

4. The method of according to claim 3 wherein the inner wherein the enclosure is circular.

5. The method of according to any of the preceding claims wherein the ram driven into the enclosure has a head contoured to match the inner surfaces of the vice jaws when they are closed.

6. The method of according to claim 4 and 5 wherein the head of the ram has a cylindrical contour.

7. The method of according to any of the preceding claims wherein the upper and lower edges of the ram surface are tapered.

8. The method of according to any of the preceding claims wherein the jaws and saddle are made from steel castings.

9. The method of according to any of the preceding claims wherein the jaws, when driven into engagement, are held in position by means of a locking device.

10. The method of according to any of the preceding claims wherein the jaws are driven into and out of engagement by means of a pair of hydraulic rams.

11. The method of according to any of the preceding claims wherein the jaws and saddle combination is demountably attached to any power source driving the power ram.

12. The method of according to any of the preceding claims wherein the jaws and saddle are equipped with cooling means.

13. Methods of restricting fluid flow in a pipe according to claim 1 and as herein described.

14. Methods of restricting fluid flow in a pipe as herein described with reference to, and as shown in, the accompanying drawings.

15. A device for restricting fluid flow in a pipe comprising a vice comprising a saddle and an associated pair of interlocking jaws and a power ram arranged to be driven through the saddle into the cavity enclosed by the jaws.

16. The device according to claim 15 in which the inner dimensions of the jaws and saddle form a circular enclosure.

17. The device according to claim 16 in which the head of the ram driven into the enclosure has a a cylindrical contour.

18. The device according to any of the claims 15 to 17 in which the upper and lower edges of the ram surface are tapered.

19. The device according to any of the claims 15 to 18 in which the jaws and saddle are made from steel castings.

20. The device according to any of the claims 15 to 19 which includes a locking device arranged to lock the jaws when engaged.

21. The device according to any of the claims 15 to 20 in which the jaws and saddle are equipped with cooling means.

22. The device according to any of the claims 15 to 21 which includes a pair of hydraulic rams is arranged to drive the jaws into and out of engagement.

23. Devices for restricting fluid flow in a pipe according to claim 15 and as herein described.

24. Devices for restricting fluid flow in a pipe as herein described with reference to, and as shown in, the accompanying drawings