EP0944766B1

EP0944766B1 - System for controlling and stopping oil drilling fires

Info

Publication number: EP0944766B1
Application number: EP97942979A
Authority: EP
Inventors: Tarmo Eino Tapani Niinivaara; Tero Tapani Hurtta; Ensi Kyösti Juhani NIINIVAARA
Original assignee: Grundstenen Metal Patent WHSS AB AB
Current assignee: Grundstenen Metal Patent WHSS AB AB
Priority date: 1996-12-16
Filing date: 1997-10-01
Publication date: 2003-04-02
Anticipated expiration: 2017-10-01
Also published as: NO992650D0; ES2196368T3; DE69720511D1; JP3920357B2; WO1998027312A1; JP2002500710A; EA199900471A1; DE69720511T2; NO312916B1; AU4462197A; EP0944766A1; AU728054B2; KR20000057582A; KR100492807B1; PT944766E; ATE236342T1; EA001253B1; NO992650L; DK0944766T3

Abstract

System for controlling oil well fires by blocking the production or drilling pipes. A box incorporating a movable piston is fitted around the pipe. The piston carries, on its forward end, a drilling cylinder (3), which can be brought to the pipe by a hydraulic piston-cylinder arrangement. Subsequently, the drilling cylinder drills through the pipe wall and after that the drilling cylinder or a separate plugging cylinder (4) is left in the drilled hole and blocks the fluid flow through the pipe. The process is remote controlled.

Description

The subject of the invention is a system to controll oil drilling fires or fires of other corresponding liquid substances. With this invention the eruption of burning substance is stopped so that the oil drilling pipe/ pipes are blocked in a way which makes it possible for the pipes to be reopened.

Presently there are three different ways to try to put out oil fires:

Water is sprayed on the seat of the fire while the fire fighter at the same time approaches the fire behind a protective shield and tries to shut down the valve of the oil pipe manually. The method is dangerous and requires a lot of water, which is not always available at the site of the fire.

By exploding the buring oil well the use of oxygen in the surrouding area is temporarily increased so much that the fire is suffocated by lack of sufficient oxygen. After this the valves and other broken equipment can be replaced. The method is very dangerous.

By drilling a new hole into the same oil well with the burning oil pipe and by pumping water into it the oil eruption is replaced by a water eruption and the fire is put out. This is an expensive and time consuming operation and the success of it cannot be guaranteed. Additionally it is dangerous to carry out.

The main parts of the equipment of this invention in question are: a hydraulic cylinder, a piston, a drilling cylinder, a plugging cylinder, a drill, a box clamp, a hydraulic motor or other power source, a blocking bolt, a hydraulic container with leads and a pressure battery and an automatic control and surveillance system. The idea is that each oil and /or gas drilling pipe within each other has its own drilling unit in accordance with pipe size. By the drilling unit we mean the drilling and plugging mechanism needed to close one oil or gas drilling pipe. Several drilling units can use a mutual energy source with its hydraulic container. In underwater conditions as on off shore oil drilling platforms the water pressure can be directed with its own mechanism to be used in the system. To create pressure also an expolsion inside a massive cylinder with pistons at both ends, can be used and this pressure is directed through a separate central container or directly into the hydraulic container. The pressure can also be taken from the oil or gas drilling pipe under the drilling units, through a drilled hole and a joint fixed to it. The necessary number of drilling units can be installed, which in the example is three.

The purpose of the system of this invention is to controll oil and /or gas fires so that the distruction of big oil and /or gas drilling equipment can be avoided. The equipment can be installed either to an oil and /or gas drilling system under construction, an oil and /or gas drilling system already constructed or even onto a burning one. Because the equipment is remote-installed and automatically controlled the oil fire does not pose a threat to humans, when the equipment has already been installed to the oil drilling system in advance and installing one on an already burning system does not necessitate going into the immediate proximity of the fire seat, on the contrary it is installed under ground. Thus as advantages of the invention we can mention that the equipment and method are safe, they save the environment, money and oil or gas.

DE-A-41 16 473 discloses a valve equipment for blocking oil and/or gas drilling pipes. The equipment comprises a drilling and blocking mechanism having a frame mounted on support of a pipe to be blocked, the frame comprising a first frame part transversal to a direction of the pipe and disposed at a first side of the pipe, and a second frame part disposed at a second side of pipe opposite to the first side; a rotatable drill for boring through the pipe, the drill being arranged inside the first frame part to move transversally in relation to the direction of the pipe; a plugging cylinder for plugging the hole bored through the pipe, the plugging cylinder being arranged inside the first frame part to move transversally in relation to the direction of the pipe; and means for moving the plugging cylinder into a plugging position at the hole bored through the pipe. The equipment does not incorporate any stuffing-box disposed inside the first frame part and the second frame parts to direct the movements of the drill-plug combination and to seal the drilled and plugged area of the pipe from the outer world, and oil or gas leaking out from the drilled and plugged area.

The invention is explained in more detail below with references to the enclosed drawing. Figure 1 shows a cross section of the equipment when the first drilling cylinder is in motion.
Figure 2 shows a cross section of the equipment when the first plugging cylinder is in place.
Figure 3 shows a cross section of the equipment when all three plugging cylinders are in place.
Figure 4 shows a cross section of the hemispherical cylinder.
Figure 5 shows a part cross section of the conical cylinder with the grinding surface.
Figure 6 shows a part cross section of the conical cylinder with protruding blade.
Figure 7 shows the equipment installed and a part cross section of the hydraulic container. The figure does not show the structure of the space constructed under ground, where the equipment is situated.
Figure 8 is a picture detailing the box clamp and the locked blocking bolt.
Figure 9 shows an application in which the drilling cylinder and the plugging cylinder (which, however, are not drawn into the figure) operate beginning from the same side of the oil and /or gas drilling pipe and the above mentioned cylinders are directed by and the cutting seam sealed by means of a stuffing box. In the figure the stuffing box on the right hand side has not been tightened into place.
In figures 1, 2 and 3 the idea is that on the right hand side of the oil and /or gas drilling pipes and the plugging cylinder there is a similar pushing and /or rotating mechanism as on the left side of the oil and /or gas drilling pipes. It is also appropriate, deviating from the drawings, that drilling units operating one after the other are placed on opposite sides of the oil and /or gas drilling pipes so that successive drillings as well as pluggings are done starting from the opposite sides of the pipes. If there are three or more drilling units around the same oil and /or gas drilling pipes each can be placed to be started from completely different directions, thus making it possible to minimize the resultant force caused to the pipes by the drilling and plugging.

When the equipment is started the pressure of the pressure batteries 10 is discharged into the hydraulic container 11, the pressure of which starts the operation of the hydraulic motor 8 and the valve. Oil flows into the hydraulic cylinder 1 which pushes the piston 2 and the piston pushes the drill 5 and the drilling cylinder 3 forward. When the drilling cylinder 3 has penetrated sufficently far that is through the oil drilling pipes 7, the mechanical reversing valve gives the comand for the drill 5 and the drilling cylinder 3 to return and further gives the order for the plugging cylinder 4 to carry out the plugging. The plugging cylinder 4 can be placed also behind the drilling cylinder 3, in which case the motion is needed in only one direction. When all the drilling units have operated also the blocking bolt can be closed when necessary. This works either hydraulically or by explosives. The plugging cylinders can operate either only so they are pushed or they can be equipped with a rotating motor for example for grinding. At the time of the plugging or after the plugging a pressurized fire extinguishing substance such as liquid nitrogen can additionally be fed into the gas or oil drilling pipe. This is fed through a hole cut into the oil or gas drilling pipe by a device like the drilling cylinder 3. All this can be done without electricity, by forced controll, in which case once the operation is started it cannot be stopped. The equipment is fixed around the oil pipes with a box clamp 6 and supported to its base. By plugging pipes of various sizes separately the pipes on top are prevented from falling. By installing sleeve pipes in place of the cut ones and by pulling out the plugs the oil drilling system can be made operational again.

The following application can be used to block the outer oil or gas drilling pipe and the explanation refers mainly to figure 9:
In addition to the parts of the invention mentioned earlier the invention also includes a stuffing box 14, a tightener 15, blocking locks 16, a plain bearing (for example a chrome strip) 17, compressed oil packing 18, a locking groove 19 and a frame groove 20. The end of the stuffing box 14 which is facing the oil or gas drilling pipe is shaped in the form of the outside wall of the pipe in question and is very sharp, this is tightened into place with a plain bearing 17 and a tightener 15 with an outside thread to the inner thread of the frame 12 of the equipment either by hand during installation or by an automatized mechanism when the equipment is started. A locking groove 19 has been shaped around the tightener 15 of the stuffing box, into which the blocking locks 16 drawn to the frame 12 by springs/ fluid pressure are pushed, when the tightener of the stuffing box has been pushed to the required depth. Additionally a frame groove 20 has been shaped into the frame 12 of the equipment, its purpose being to prevent, in addition to the tightener 15 of the stuffing box, the loosening of the stuffing box 14 when it has reached the fixed depth. The purpose of the stuffing box 14 which has been tightened into place and which is very sharp at the oil or gas drilling pipe 7 end and which is of a very hard material, is to seal the plugging seam of the oil or gas drilling pipe 7 being drilled and plugged and to direct the movement of the drilling-plugging combination 3-4 travelling within it. The seam between the stuffing box 14 and the axle 13 is sealed with a compressed oil packing. As the drilling proceeds the pieces drilled loose from the oil or gas drilling pipe 7 are left in the drilling-plugging combination 3-4.

The surveillance and control of the valve can operate:

1. By using known methods from the processing and automation technology.

2. By electrically measuring changes with sensors from the magnetic field of the system, these changes are caused for example by changes in the following quantities: flow rate, flow direction, temperature, pressure, stability. Changes taking place in the magnetic field are noted electrically by changes in several resistors, which are transistor directed and integrated by computer, and the operation of the valve is controlled by the limiting values coded into the computer. The underwater surroundings of the valve and changes in it can also be surveilled throught this method, and any observations, for example the threat of terrorism, is passed on to the surveillance and control terminal.

3. By analysing and coordinating quantities, such as temperature, pressure, speed of revolution and travelling speed, and changes in them measured by sensors in the tip of the drill and on the axle.

To control the valve we can use:

1. Independent valve controls, electrically connected: closing the valve needs only one command.

2. Control directly or indirectly from the hydraulic valve.

3. A hydraulic valve operated by pneumatics.

The operations can be connected either manually or automatically, in which case the system is started by the safety release of the independently closing system. As measuring quantities we can use temperature, gas content, pressure, flow, jolts, mechanics, electrical techniques or other such quantities, which give the valve instructions automatically also when it is not possible to do this by human power.

Sensors indicating operation can be installed on the valve which will show the operating status of the valve.

1. A pressure sensor in the hydraulic container showing the valve has started operating, indicating the working pressure of the oil.

2. A gauge showing the amount of oil indicating the distance of motion:

the amount of oil going into the cylinder indicates the distance of motion
the pressure sensor on the return side of the cylinder indicates the operation of the return motion.

3. The pressure sensor in the plugging cylinder indicates the plugging motion.

4. The sensor indicating the rotating of the drill is situated on the axle of the drill

5. A sensor situated in the tip of the drill can measure prevailing quantities.

Automatic data processing uses these quantities to form a picture detailing the operation of the valve onto the computer terminal

Claims

Valve equipment for blocking oil and/or gas drilling pipes, comprising:

a drilling and blocking mechanism having a frame (12) mounted on support of a pipe (7) to be blocked, a box clamp (6) for mounting the frame to the pipe, the frame comprising a first frame part transversal to a direction of the pipe and disposed at a first side of the pipe, and a second frame part disposed at a second side of pipe opposite to the first side; an axle (13) having a drilling cylinder (3) provided with a drill (5) for boring through the pipe, the drill being arranged inside the first frame part to move transversally in relation to the direction of the pipe, a power source (8) for rotating the axle, a piston (2) attached to the axle and a hydraulic cylinder (1) for moving the piston and the axle in direction of the axle, the valve equipment comprises a blocking plunger (9) which can be moved in a pipe blocking position after the drill has bored through the pipe, a pressure battery (10) and a hydraulic container (11) with lines; a plugging cylinder (4) for plugging the hole bored through the pipe, the plugging cylinder being arranged inside the first or the second frame part to move transversally in relation to the direction of the pipe; and means for moving the plugging cylinder (4) into a plugging position at the hole bored through the pipe; characterized in that the drilling and blocking mechanism comprises stuffing boxes (14) made of hard material which are disposed inside the first frame part and the second frame part between said frame part and the drill and the plugging cylinder for directing the movement of the drill and the plugging cylinder, the stuffing boxes having sharp front ends facing the pipe, the front ends being shaped to the form of the outer wall of the pipe, and the stuffing boxes being movable and guided by said frame part transversally towards the pipe from opposite sides of the pipe for sealing the plugging seam of the pipe, tighteners (15) for pushing the stuffing boxes against the pipe; and locking means (16, 19, 20) for locking the tighteners into a fixed position in relation to the frame parts.
Valve equipment as claimed in claim 1, wherein a guide means of the frame (12) is provided with an inner thread and one of the tighteners (15) is provided with an outer thread for co-operation with said inner thread.
Valve equipment as claimed in claim 1 or 2, wherein plain bearings (17) are arranged between the tighteners (15) and their associated stuffing boxes (14).
Valve equipment as claimed in any of claims 1 to 3, wherein the locking means comprises a frame groove (20) at a cylindrical inner surface of the frame part, spring-biased blocking locks (16) in the frame groove, and a locking groove (19) around an outer surface of the tightener (15) for receiving the blocking locks.
Valve equipment as claimed in any of claims 1 to 4, wherein the drilling and blocking mechanism comprises a compressed oil packing (18) for sealing an axle (13) which rotates the hydraulically rotatable drill (15) to the stuffing box (14).
Valve equipment as claimed in any of 1 to 5, further comprising a plurality of drilling and blocking mechanisms arranged consecutively along the pipe (7), wherein, in each two adjacent drilling and blocking mechanisms, the boring directions of the drills (5) through the pipe are opposite to each other.
Valve equipment as claimed in claim 6, wherein in each two adjacent drilling and blocking mechanisms, the blocking directions of the plugging cylinders (4) are opposite to each other.
Valve equipment as claimed in any claims 1 to 7, wherein the valve equipment comprises at least three drilling and blocking mechanisms.
Valve equipment as claimed in any of claims 1 to 8, wherein the drilling and blocking mechanism comprises a mechanism to utilize hydrostatic water pressure and an automatic control and surveillance system.
Valve equipment as claimed in any of claims 1 to 9, wherein a point of the drilling cylinder (3) is ball-shaped and provided with a blade which is hydraulically projected and pulled back, whereby the drilling cylinder (3) also comprises the plugging cylinder (4).
Valve equipment as claimed in any of claims 1 to 10, wherein the drilling cylinder (3) is conical and is provided with a dynamic drill size regulator, and the plugging cylinder (4) is conical.
Valve equipment as claimed in any of claims 1 to 11, wherein the plugging cylinder (4) is hollow and lockable by oil pressure or explosive.
Valve equipment as claimed in any of claims 1 to 12, wherein the drilling cylinder (3) is a cylinder with a blade on its point.
Valve equipment as claimed in any of claims 1 to 13, wherein the drill (5) is disposed centrally at an end of the drilling cylinder (3).
Valve equipment as claimed in any of claims 1 to 14, wherein the drilling cylinder (3), plugging cylinder (4) and the drill (5) are disposed to receive their forward motion energy from the pressure batteries (10) through the piston (2), the axles (13), the hydraulic cylinder (1) and the hydraulic container (11) in addition to the lines.
Valve equipment as claimed in any of claims 1 to 15, wherein the drilling cylinder (3) and the drill (5) are disposed to receive rotating motion energy from the pressure batteries (10) through the piston (2), the axles (13), a hydraulic motor used as the power source (8), the hydraulic container (11) and the lines.
Valve equipment as claimed in any of claims 1 to 16, wherein the box clamps (6) have a two-part structure for installation around the pipe (7).
Valve equipment as claimed in any of claims 1 to 17, wherein an inner side of the box clamp (6) is conical and provided with a thread.
Valve equipment as claimed in any of claims 1 to 18, wherein the blocking plunger (9) is lockable in place using one of explosives and hydraulics.
Valve equipment as claimed in any of claims 1 to 19, wherein the locking plunger (9) is wider than the pipe (7) and has a tapering v-formed point.
Valve equipment as claimed in any of claims 1 to 20, wherein the drilling cylinder (3) and the plugging cylinder (4) each have an outside diameter larger than an inner diameter of the pipe (7) and smaller than an outside diameter of the pipe.
Valve equipment as claimed in any of claims 1 to 21, wherein a blade of the drilling cylinder (3) is disposed to project from the drilling cylinder (3) when the drilling cylinder starts to rotate in a first rotation direction and retract into the drilling cylinder when the rotation direction changes.
Valve equipment as claimed in any of claims 1 to 22, wherein an outside surface of the drilling cylinder (3) includes a grinding surface.
Valve equipment as claimed in any of claims 1 to 23, wherein the drilling cylinder (3) is disposed to act as the plugging cylinder (4), and the drilling cylinder is arranged to be expandable using one of hydraulic and explosive force.
Valve equipment as claimed in any of claims 1 to 24, wherein the drilling cylinder (3) and the plugging cylinder (4) are both situated on one of a same side of the pipe (7) and different sides of the pipe.
Valve equipment as claimed in any of claims 1 to 25, wherein the drilling units are placed on opposite sides of the pipe so that successive drillings are started from different sides of the pipe, and successive pluggings are started from different sides of the pipe.
Valve equipment as claimed in any of claims 1 to 26, wherein the valve equipment is arranged to be installable on drilling system controlled by a plate.
Valve equipment as claimed in any of claims 1 to 27, wherein, in underwater conditions, hydrostatic water pressure is directed by a separate energy conversion mechanism into energy to be used by the drilling system.
Valve equipment as claimed in any of claims 1 to 28, further comprising means for measuring changes in magnetic field of the drilling system for continuous monitoring of the drilling unit as well as surroundings and for taking action required by the measured changes in magnetic field.
Valve equipment as claimed in any of claims 1 to 29, comprising equipment for measuring the changes in the magnetic field electrically, the changes being caused by changes in at least one of flow rate, flow direction, temperature, pressure, stability and material surrounding the pipe.
Valve equipment as claimed in any of claims 1 to 30, wherein the equipment for measuring the changes in magnetic field includes resistor and transistor sensors coupled to a computer, information on changes in electrical properties of the sensors being received and analyzed by the computer.
Valve equipment as claimed in any of claims 1 to 31, wherein information collected by the resistors and transistors is integrated into coded limiting values in the computer, the code limiting values being used in controlling operation of the valve and being transferred to surveillance and control terminal.
Valve equipment as claimed in any of claims 1 to 32, further comprising a massive cylinder coupled via leads to provide energy to the valve equipment from pressure caused by an explosion within the cylinder.
Valve equipment as claimed in claim 33, wherein air pressure caused by the explosion is directed into one of the hydraulic container (11) and a separate central container coupled to the hydraulic container, the air pressure being coupled to the hydraulic container where the air pressure is first directed into the separate central container.
Valve equipment as claimed in any of claims 33 or 34, further comprising two axially parallel pistons positioned within in the massive cylinder and situated on different sides of a charge of explosive material.
Valve equipment as claimed in any of claims 1 to 35, further comprising a separate joint couplable to a hole drilled by the pipe to couple one of negative and excess pressure in the hole to the valve equipment as an energy source for powering the valve equipment.
Valve equipment as claimed in any of claims 1 to 36, further comprising a programmable computer coupled to control the valve equipment and to receive information from sensors disposed to measure operating conditions.
Valve equipment as claimed in any of claims 1 to 37, further comprising a transmitter to transmit information received from the sensors to a remote control center.
Valve equipment as claimed in any of claims 1 to 37, further comprising a source of a pressurized fire extinguishing substance couplable to be fed through a hole drilled in the pipe above the plugging unit or plugging units, through a separate joint.
Valve equipment as claimed in any of claims 1 to 37, wherein the source of pressurized fire extinguishing substance is arranged to feed the fire extinguishing substance into the pipe at time corresponding to one of a time when the pipe is plugged by the plugging cylinder and a time independent of when the pipe is plugged by the plugging cylinder.