GB2070102A

GB2070102A - A Coupling Device for Restraining and Regulating an Uncontrolled Gushing Out From an Oil or Gas Drilling

Info

Publication number: GB2070102A
Application number: GB8005870A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-02-21
Filing date: 1980-02-21
Publication date: 1981-09-03
Also published as: GB2070102B

Abstract

The coupling device is intended for closing a drilling pipe, from which oil or gas gushes out in an uncontrollable amount. A housing (1%) comprising a branch pipe (19) is carried downwards about the drilling pipe and fixed by means of tightening means such as hydraulic cylinders (7) comprising pistons pressing closure sections (4%) with claws against the wall of the drilling pipe. At the same time the closure sections are sealingly abutting each other edge to edge and thereby forming a pyramidal or conical closure. An increased pressure within the housing (1%) implies that the capability of the closure sections for holding the housing on the drilling pipe is increased. When a closing valve mounted in advance on the branch pipe (19) is closed the pressure transmitted to the top side of the closure sections (4%) is further increased. Through the pipe (19) the coupling device may be coupled to existing installations. <IMAGE>

Description

SPECIFICATION A Coupling Device for Restraining and Regulating an Uncontrolled Gushing Out From an Oil or Gas Drilling The invention relates to a coupling device for restraining and regulating an uncontrolled gushing out through a pipe from an oil or gas drilling, said coupling device comprising a housing which may be situated on the pipe, and in which displaceable sealing and fastening means are provided, which with the co-operation of the pressure in the fluid gushing out may be carried towards the pipe wall so as to tightly engage said pipe wall.

In case of heavy leaks of liquid or gas from open pipe ends, e.g. by a so-called blow out on a drilling platform or at the bottom of the sea whereby there is no other way of stopping the medium flowing through the pipe, it may be very difficult or even impossible to mount a closing valve at the end of the pipe in order to stop the medium gushing out.

It is known to utilize the pressure of the medium in a pipe for pressing a gasket in a pipe connection tightly againts a pipe wall.

Furthermore, it is known from German Offenlegungsschrift No. 2,747,804 to hold an end stop provided with a pipe stub having a closing valve at the pipe mouth by utilizing the pressure within the interior of the pipe. This end stop forms a plug at the end of the pipe and comprises a circular groove receiving the pipe in such a manner that clamping and gasket rings radially movable in circumferential grooves in the end stop may be pressed in radial direction towards the outer and inner side of the pipe wall when influenced by a pressure medium of an exterior pressure source and with co-operation of the pressure within the gas or the liquid in the pipe.

This coupling device is for instance well suited for pressure tests of pipes. However, such a coupling device cannot be mounted on the pipe when the liquid or the gas gushes out at a high velocity and under high pressure.

The object of the invention is to provide a coupling device of the above type, which when mounted on a pipe end or at a leak may stop or to an essential degree restrain the gushing out of oil or gas. An additional object of the invention is to shape the coupling device in such a manner that according to requirement it may relatively easy be mounted on a pipe, from which an uncontrolled gushing out takes place.

The coupling device according to the invention is characterised in that a plurality of closure sections in the form of conical surface segments or substantially triangular sheets are provided in the housing, said closure sections being swingable or displaceable in radial planes from a position, in which they are mutually separated, into a position, in which they are located edge to edge and form a pyramidal or conical, tight sealing between the housing and the pipe, and in such a manner that the pressure in the fluid gushing out may freely influence the outer side of the pyramide or the cone.

The pressure of the fluid on the outer side of the pyramide or the cone implies that even at a heavy blow out it is possible to obtain a reliable grip, with which the coupling device can be secured to the pipe or in some cases, in which the coupling device has been fixed in advance, the pipe may be secured so as not to be shot out at a blow out.

According to a preferred embodiment of the coupling device the closure sections are located at the peripheral rim of the lowermost, open end of the housing and are movable inwards towards a central through pipe by means of hydraulic, pneumatic or mechanical tightening means such as piston-cylinder mechanisms or rack mechanisms located on the housing. The housing may for instance be an upwardly pointed, bell shaped or conical bushing, which may be mounted on a pipe stub or optionally by means of hinges be closed about a pipe. The sheet-shaped closure sections are sealingly connected to the wide end of the bushing, whereas they at their opposite ends carry claws or teeth adapted to grip about the outer side of a pipe.At the narrowest, uppermost end of the bushing a closing valve may be located, and as the closing valve is being closed the pressure in the flowing medium is transmitted to the top side of the closure sections, and the more the valve is closed the more said pressure presses the closure sections against the pipe wall. The coupling device may optionally be coupled to existing installations, and the tightening means may be provided with a hydraulic or mechanical locking or clamping device maintaining the closure sections in the permanently tightened position, also when the pressure in the fluid is reduced.

At the top the housing may also be confined by a top wall, and the closing valve may be located on a branch pipe extending from a spot adjacent the top of the housing.

According to another embodiment of the coupling device according to the invention, the housing may comprise two sets of closure sections, which in the closed position form two oppositely directed pyramidal or conical closures on their respective sides of the leak. Such a coupling device may be located about a pipe for stopping the gushing out of a leak in the pipe wall.

According to a further embodiment of the coupling device according to the invention, the housing may be fixedly mounted on a pipe stub, and the closure sections may be located in the uppermost part of the housing and in such a manner that they in the closed position form a pyramide or a cone with a spigot end turning downwards. Such a coupling device is particularly well suited for preventing a broken off bore tube from being shot out or for forming a quickly closing safety valve. The closure sections may for instance be thus shaped or provided with such sealing means that without gripping about a pipe they may form a tight sealing in the housing.

The coupling device according to the invention may also be used for cleaning the surface of the sea for oil gushing out of a bore tube. In this case the housing open at the top comprises a bottom with a central opening receiving a pipe stub, and the closure sections are displaceable along the bottom of the coupling device for tightly securing the housing to the pipe stub.

The invention will be described below with reference to the accompanying drawing, in which: Fig. 1 is an axial sectional view through an embodiment of the coupling device according to the invention, Fig. 2 is a sectional view along the line A-A of Fig. 1, Figs. 3 to 6 illustrate details of locking means for holding the closure sections to the housing in the idle position.

Fig 7 illustrates a detail concerning the uppermost end of the closure sections of Fig. 1, Fig. 8 illustrates a coupling device mounted on a pipe stub at the bottom of the sea, Figs. 9 and 10 are variations of the coupling device according to the invention including closure sections with the spigot ends turning downwards, Fig. 11 is a further variation of the coupling device according to the invention, Figs. 12 and 13 are diagrammatical views of mechanical locking and clamping devices for securing the closure sections in the tightened position, Fig. 14 illustrates an additional embodiment of the coupling device according to the invention, and Figs. 1 5 and 16 illustrate a coupling device with a housing comprising hinged halves.

The coupling device illustrated in Figs. 1 and 2, which also may be designated a valve claw, comprises a conical housing 1 extending at the top into a pipe stub 2 and at the bottom into a wide rim portion 3, whereby said housing is open at both ends. A plurality of closure sections 4 in the form of conical surface segments are provided in the housing. Each conical surface segment is at two points along a common generatrix through the middle of the segment connected to two piston rods 6 displaceable in hydraulic or pneumatic cylinders 7 secured to the outer side of the housing 1. Each segment 4 may thus by means of the piston-cylinder mechanisms 6, 7 perform a translatoric movement in radial direction within the housing while it at the lowest end sealingly engages a surface in the rim portion 3 of the housing.At the opposite end, each segment 4 is curved inwards in such a manner that the segments together form an axial rim surface shaped with circumferential locking grooves with intermediate, sharp edged teeth or ribs forming claws 5, When it is desired to stop a heavy, uncontrolled leak of liquid or gas from the open end of a pipe not shown, the housing with the pipe stub 2 in advance provided with a closing valve is carried an appropriate distance downwards about the pipe end and secured thereto by actuating the piston-cylinder mechanisms 6, 7 in such a manner that they press the conical surface segments 4 inwards.

Thereby the claws or teeth 5 may engage the outer side of the pipe along the entire periphery thereof, whereby the segments act as tightening means. When the closing valve mounted on the pipe stub 2 subsequently is slowly closed, the pressure within the pipe with the medium gushing out through the pipe stub 2 is transmitted to the space between the wail in the housing 1 and the segments 4. When the valve then is further closed, the pressrue increases in such a manner that the claws or teeth 5 are strongly pressed against the pipe wall and fix the housing 1 permanently. Subsequently, pressure hoses 1 5 feeding pressure medium to the cylinders 7 during the first part of the mounting are removed and do not prevent further work, e.g. in connection with coupling of the closing valve to existing installations.

As indicated in Figs. 12 and 13, the closure sections 4 may be maintained in the tightened position by means of spring-influenced pawls 1 5 engaging a rack 1 6 on the outer side of each closure section or by means of a corresponding locking and clamping device also functioning when the pressure in the fluid is reduced. Instead of hydraulic or pneumatic tightening means for the first tightening of the sections against the pipe, mechanical tightening means may be employed. The movement of the segments 4 by means of hydraulic means is, however, advantageous since the movement may easily be remote-controlled at a safe distance from the pipe, from which the gushing out is to be stopped.

The movement of each section might also be performed by means of a single piston-cylinder mechanism, if they instead of being translatorically displaceable are swingably mounted at their lowermost end rims, e.g. by means of hinges or flexible connecting means.

The cross section of the housing is usually circular or square, but other types of cross sections are also possibie, e.g. hexagonal or octagonal, by using a corresponding number of closure sections.

During the storing and the first part of the mounting the closure sections 4 are preferably held to the inner side of the wall of the housing 1.

Such a holding may be provided in the manner diagrammatically indicated in Figs. 3 to 6. On the outer side, each segment 4 comprises an eye, and in the wall of the housing 1 a shaft 10 is mounted.

At one end this shaft carries a hook 9 engageable in the eye, and at the opposite end it carries a control or pull arm 11 rendering it possible for the hook to disengage the eye when the segment is to be released. The segments 4 may be quickly released through a pull in a wire 12 connected to all the control arms 11 and extending along the periphery of the housing in pulleys 13, cf. Fig. 6.

Fig. 5 illustrates this form of locking, seen in a direction towards a segment 4, whereby the portion of the housing 1 being in front of the segment has been removed.

Fig. 7 illustrates how circumferential sharp edged teeth 5 are provided in an axial rim surface in each of the closure sections 4 closely abutting each other through gaskets 14 when gripping about a pipe having the outer dimension, for which the coupling device is intended to be used.

Fig. 8 illustrates an embodiment of the coupling device according to the invention comprising a cylindrical housing 1'. This housing 1' comprises two halves connected by means of hinges 16 about a drill pipe stub 17. By means of hydraulic cylinders 7 the closure section 4' are connected in a tightly sealing manner to the pipe stub 1 7 in such a manner that they close a central opening in the bottom of the coupling device. A branch pipe 19 on top of the housing may be provided with a closing valve. An increased pressure within the housing implies also in this case that the capability of the closure sections for maintaining the housing 1' on the pipe stub 17 is increased.According to an embodiment, in which the housing 1' of Fig. 8 comprises no top wall, but is open at the top, the housing may be used for reception of oil when cleaning the sea over a leaking source of oil.

The coupling device illustrated in Fig. 9 comprises a housing 1" with closure sections 4", which in the closed position form a pyramide or a cone with the spigot end turning downwards. The housing 1" is formed integral with a through pipe 20, and in the closed positions, the sections 4" form a tight sealing between the inner wall of the housing 1" and the interior of the pipe 20. The outflowing gas, the pressure of which influences on the outer side of the closure sections 4", continues upwards through one or more pipes 21, which may be provided with closing valves. The closure sections 4" may also be shaped in such a manner that they tightly surround a pipe extending centrally through the pipe 20.Should such an interior pipe break off below the housing 1", it may be prevented from being shot out by means of the closure sections 4".

This also applies to the embodiment illustrated in Fig. 10, whereby the housing 22 is not provided with an outiet pipe 21. In this case oil or gas can only flow out through a central pipe 23, or the closure sections 4" may form a closure, whereby the housing 22 functions as a closing valve on the pipe 20.

Fig. 11 illustrates a coupling device similar to the embodiment of Fig. 1 and comprising a housing 1 and closure sections 4 as well as a pipe stub 2. On the pipe stub 2, a pair of permanent slide valves 24 are provided. Besides, the coupling device functions as described in connection with Fig. 1. The reference numeral 25 indicates transporting means, through which the coupling device may be moved along a pipe 23, which it surrounds.

The coupling device illustrated in Fig. 14 comprises a housing 1"' secured to a pipe 23 by means of conical sheets 26. At the uppermost rim of the housing, a plurality of closure sections 4"' are hinged or flexibly connected to each other in such a manner that they may swing inwards and form a tight seal in the form of a pyramidal surface with the spigot end turning downwards.

According to a variation, the sheets 26 may also in this case be shaped as movable closure sections corresponding to the closure sections 4 of Figs. 1 and 11.

Fig. 1 5 is a sectional view of an embodiment of the coupling device according to the invention, and Fig. 1 6 illustrates said embodiment from the outside. This embodiment may be located about a pipe, since it comprises two sections mutually connected at the hinge 1 6. At the rim diametrically opposite the hinges, the halves of the housing are connected by means of hydraulic or mechanical locking devices 27.

It is to be understood, that many modifications of the coupling device according to the invention may be carried out without deviating from the scope of the invention. Thus the closure sections may for instance be shaped or provided with such sealing means that they may both grip tightly about a pipe and may be completely closed without gripping about a pipe. The housing of the closure sections may also be shaped in such a manner that it can be located within a large pipe and function as a closing valve gripping about an interior pipe. Finally, the housing may according to the invention be shaped with two sets of closure sections, the spigot ends of which opposing in the closed positions. Such a coupling device may be used for mounting about a leak in a pipe, whereby the closure sections are located on their respective sides of the aperature in the pipe and are pressed tightly thereagainst by the fluid gushing out.

Furthermore, a branch pipe on the closed housing of a coupling device may also be used for blowing in a fluid co-operating in pressing the closure sections against each other in case no oil or gas gushes out of a pipe stub.

Many modifications and combinations of the above embodiments are possible. A set of closure sections may for instance form a claw gripping in a sealing manner about a bore tube, whereas a second set of closure sections forms a tight sealing when the bore tube is gone.

Claims

1. A coupling device for restraining and regulating an uncontrolled gushing out through a pipe from an oil or gas drilling, said coupling device comprising a housing which may be situated on the pipe, and in which displaceable sealing and fastening means are provided, which with the co-operation of the pressure in the fluid gushing out may be carried towards the pipe wall so as to tightly engage said pipe wall, characterised in that a plurality of closure sections in the form of conical surface segments or substantially triangular sheets are provided in the housing, said closure sections being swingable or displaceable in radial planes from a position, in which they are mutually separated, into a position, in which they are located edge to edge and form a pyramidal or conical, tight sealing between the housing and the pipe, and in such a manner that the pressure in the fluid gushing out may freely influence the outer side of the pyramide or the cone.

2. A coupling device as claimed in claim 1, characterised by the closure sections being located at the peripheral rim of the lowermost, open end of the housing and being movable inwards towards a central through pipe by means of hydraulic, pneumatic or mechanical tightening means such as piston-cylinder mechanisms or rack mechanisms located on the housing.

3. A coupling device as claimed in claim 2, characterised by the tightening means being provided with a hydraulic or mechanical locking and clamping device for securing the closure sections in a permanent tightened position, also when the pressure in the fluid is reduced.

4. A coupling device as claimed in claim 2, characterised by the housing at the top being confined by a top wall, and by a branch pipe provided with a closing valve extending from a spot adjacent the top of the housing.

5. A coupling device as claimed in claim 1 to be located above a leak in a pipe, characterised by the housing comprising two sets of closure sections, which in the closed position form two oppositely directed pyramidal or conical closures on their respective sides of the leak.

6. A coupling device as claimed in claim 2, characterised by the housing being fixedly mounted on a pipe stub, and by the closure sections being located in the uppermost part of the housing and in such a manner that they in the closed position form a pyramide or a cone with a spigot end turning downwards.

7. A coupling device as claimed in one or more of the preceding claims, characterised by the housing in one or more axial planes being divided up into a plurality of preferably hinged segments, which mutually may be tightly joined after location about a pipe.

8. A coupling device as claimed in claim 1 with a bottom comprising a central opening receiving a pipe stub, characterised by the closure sections being displaceable along the bottom of the coupling device for tightly securing the housing to the pipe stub, and by the housing forming an oil reception tank open at the top for restraining the leakage of oil.

9. A coupling device as claimed in claims 1 and 2 with closure sections, which in the idle position are secured to the inner side of the wall of the housing, characterised by each closure section on the outer side comprising an eye or a corresponding fastening means, in which a hook on a shaft pivotally mounted in the housing may engage, said shaft on the outer side of the housing carrying a control arm, and by the control arms of all the closure sections being connceted to a wire extending along the outer side of the housing in such a manner that at a pull in the wire all the hooks may disengage the corresponding eyes.

10. A coupling device as claimed in any one of the preceding claims, characterised by the closure sections being thus formed or provided with such tightening means that they may form a tight sealing in the housing without gripping about a pipe.

11. A coupling device substantially as described above with reference to the accompanying drawing.