RU2822188C1 - Electrical downhole disconnector - Google Patents

Abstract

FIELD: oil, gas and coke-chemical industry.

SUBSTANCE: invention relates to oil and gas industry and can be used in downhole operations when it is necessary to disconnect one part of equipment from another. Device contains a head with a disconnection mechanism arranged in it, which consists of an adapter and a housing with a collet installed in it, having a fixing piston, and connected to the adapter. Disconnection mechanism drive is connected to the disconnection mechanism housing, which includes a housing with a cover, installed in it a cylinder equipped with a slide valve and a spring, an upper spring-loaded contact installed in the cover, a lower spring-loaded contact installed in the cylinder, and a spool valve locking device.

EFFECT: reduced time of actuation of device for disconnection of assembly parts, reduced time of stuck assembly lifting and creation of emergency.

5 cl, 5 dwg

Description

The invention relates to the oil and gas industry and can be used when carrying out downhole work if it is necessary to disconnect one piece of equipment from another.

A downhole disconnector is known, including upper and lower detachable parts connected by a lock, unlocked by a movable sleeve, which can move under the influence of excess pressure, and the upper part of the disconnector is made in the form of a sub, to which is connected a lock made in the form of a collet, fixed by a movable sleeve, having the ability to move under the influence of excess pressure created in the annulus, and connected to a piston placed in an annular cylindrical cavity, hydraulically connected to the internal cavity of the pipe string, and the collet has a multifaceted groove and is connected to a sub having a connecting thread on top, the lower part of the disconnector made in the form of a rod, the upper end of which has a multifaceted shape and is placed in a multifaceted groove of the collet, and its lower end has a connecting thread (see patent RU 2278945, IPC 8 E21B 17/06, 2006).

The disadvantage of this device is the need to create a pressure difference in the annular and casing spaces to activate (disconnect) the device in the well, while the pressure difference must be sufficient to move the piston upward. To fulfill this condition, it is necessary to strictly adhere to the design dimensions of the device, which are tied directly to the standard size of the production string of the well into which this downhole disconnector is lowered.

A device is known for disconnecting equipment during downhole operations with simultaneous disconnection of electrical or hydraulic lines. The device includes upper and lower parts, hermetically inserted and fixed relative to each other. The device is designed with the ability to simultaneously disconnect equipment and electrical or hydraulic lines. The locking elements are made in the form of shear pins, or in the form of shear rings, or elastic ring elements located in the groove, or collet or spring clamps. Sealing is ensured by sealing elements in the form of rings, seals, cuffs, and the electrical or hydraulic line is secured using clamps on the upper and lower parts of the device for disconnecting equipment during downhole work (see RF patent 2570697, IPC E21B 17/06 (2006.01), E21B 29/04 (2006.01), 2015).

The disadvantage of this device is the need to tension the cable to cut the shear elements of the disconnector. If a cable is damaged, its load-bearing capacity is reduced, which can lead to cable breakage when attempting to disconnect.

A common disadvantage of all of these devices is that the disconnectors are made with mechanical and hydraulic starting systems, which have a large response inertia.

No similar solutions have been identified in the existing level of technology.

The technical problem, the solution of which is provided by using the invention, is to ensure the planned separation of parts of the assembly lowered into the well from each other in the event of an emergency or emergency situation (for example, stuck perforation system) using an address key using an electrical control signal.

The technical result achieved as a result of the use of all the essential features of the claimed invention is to reduce the response time of the device for separating parts of the assembly and, as a consequence, to ensure a reduction in the time of lifting a stuck assembly and prevent the creation of an emergency situation.

The stated technical result is achieved due to the fact that an electric downhole disconnector has been developed, containing a head with a disconnection mechanism placed in it, consisting of an adapter and a housing with a collet installed in it, having a piston-clamp and connected to the adapter, and a disconnection mechanism drive made in in the form of a quick-release cartridge connected to the housing of the release mechanism.

The head is made in the form of a hollow body and is equipped with a sealed fixed contact.

The locking piston is equipped with contacts installed into it on opposite sides and connected into an electrical line.

The drive of the disconnection mechanism is made in the form of a quick-detachable cartridge, consists of a housing with a cover and a cylinder installed in them, equipped with a spool and a spring, upper and lower spring-loaded contacts and a spool fixation device.

The spool fixation device contains a worm gear with an output shaft, a lever swinging on an axis fixed in the body of the quick-release cartridge, a fishing line fixed at one end to the lever and the other to the output shaft of the worm gear and a stop.

The spool fixation device can be made of a lead nut, a micro-electric motor connected to a DC source and equipped with a gearbox, a lead screw and a relay.

The developed electric downhole disconnector contains a head with a disconnection mechanism placed in it, consisting of a housing with a collet installed in it with a piston-clamp connected to an adapter, and a disconnection mechanism drive made in the form of a quick-detachable cartridge connected to the disconnection mechanism housing provides time reduction to disconnect the assembly and, as a result, reduces the time for lifting a stuck assembly and prevents the creation of an emergency situation.

The disconnection mechanism, consisting of an adapter and a housing with a collet installed in it, connected to the adapter and equipped with a locking piston, reduces the time for disconnecting the assembly while simultaneously disconnecting the electrical line, which also reduces the time for lifting the stuck assembly.

The drive of the disconnection mechanism (quick-release cartridge) ensures the operation of the separation mechanism, reducing the response time of the device for separating parts of the assembly, respectively, the time of lifting the stuck assembly and preventing the creation of an emergency situation.

Figure 1 is an assembled view of an electrical downhole disconnector;

Figure 2 - disconnection mechanism;

Fig.3 - drive of the release mechanism (quick-release cartridge);

Figure 4 is a general view of the triggered device until the disconnection is completed;

Figure 5 is an example of the location of an electrical downhole disconnector in the layout.

The electric downhole disconnector (hereinafter referred to as ERA) is designed for emergency disconnection of parts of the assembly lowered into the well from each other in the event of an emergency or emergency situation (for example, stuck perforation system).

List of elements of the proposed electric borehole disconnector:

1 - release mechanism;

2 - drive of the release mechanism (quick-release cartridge);

3 - head;

4 - housing of the release mechanism;

5 - collet;

6 - collet petals;

7 - adapter;

8 - axial hole of the collet;

9 - piston-clamp;

10 - upper contact;

11- lower contact;

12- wire;

13 - adapter boring;

14 - shear pins;

15 - quick-release cartridge body;

16 - quick-release cartridge cylinder;

17 - spool of quick-release cartridge;

18 - spring;

19 - emphasis;

20 - upper spring-loaded contact;

21 - lower spring-loaded contact;

22 - electric igniter;

23 - address key;

24 - quick-release cartridge cover;

25 - output shaft of the worm gear of the spool fixing device;

26 - lever of the spool fixation device;

27 - axis of the spool fixation device;

28 - fishing line;

29 - hole in the release mechanism housing;

30 - radial holes in the cylinder 16 of the quick-release cartridge;

31 - sealed fixed contact of head 3;

32 - pins;

33 - cable;

34 - lower sealing ring;

35 - radial holes in the housing 4 of the release mechanism;

36 - axial hole in the cylinder 16 of the quick-release cartridge;

37 - working cavity of the disconnection mechanism;

38 - sealing rings of the collet.

The main components of the ERA are the disconnection mechanism 1 (see Fig. 1, 2), the drive of the disconnection mechanism (quick-release cartridge) 2 (see Fig. 1, 3) and the head 3 (see Fig. 1).

The housing 4 of the separation mechanism 1 is installed in the head 3. The cylinder 16 of the drive of the separation mechanism (quick-release cartridge) 2 and the back side of the collet 5 are installed in the housing 4 of the separation mechanism on opposite sides. The petals 6 of the collet 5 (see Fig. 2) are installed in the adapter 7 , left in the arrangement after disconnection. The adapter 7 is fixed to prevent rotational movement relative to the collet 5 with pins 32. In the axial hole 8 of the collet 5 there is a piston-clamp 9 with upper 10 and lower 11 contacts connected into an electrical line by wire 12.

The upper contact 10 is made sealed to ensure a pressure difference between the cavities of the hydraulic cylinder formed by the body 4, the collet 5, the adapter 7, the piston-clamp 9. The piston-clamp 9 in the initial position blocks the axial movements of the collet 5 by spreading the petals 6 of the collet in the bore 13 of the adapter 7. The piston-clamp 9 itself is fixed in the collet 5 during assembly using shear pins 14 to prevent its spontaneous movement and, as a consequence, separation of the arrangement.

The drive of the release mechanism 2 (see Fig. 3) is made in the form of a quick-release cartridge. The quick-release cartridge 2 consists of a housing 15 with a cover 24 and is installed in the head 3 (see Fig. 1). In the axial hole of the housing 15 there is a cylinder 16 of a quick-detachable cartridge, equipped with a spool 17 and a spring 18. In the cover 24 of the quick-detachable cartridge 2 there is an upper spring-loaded contact 20 connected to the address key 23. A lower spring-loaded contact 21 is installed in the cylinder 16 of the quick-detachable cartridge. The free part of the cylinder 16 of the quick-release cartridge 2 is installed in the hole 29 of the housing 4 of the release mechanism. The cylinder 16 of the quick-detachable cartridge, together with the spool 17, movably installed in the cylinder 16, separates the working cavity 37 of the disconnection mechanism 1 from the well fluid. The spool 17 is supported by a spring 18 and fixed in its original position through the stop 19 by a spool fixation device. The spool fixation device may consist of a worm gear with an output shaft 25, a lever 26 swinging on an axis 27 fixed in the housing 15, a fishing line 28 and a stop 19 (see Fig. 3). An electric igniter is installed in housing 15. 22. The fishing line 28 is fixed at one end to the lever 26, the other to the output shaft 25 of the worm gearbox and passes through the electric igniter 22. The spool fixing device can be made in a different way, described below.

The movement of the spool 17 against the force of the spring 18 and fixing it in its original position is carried out by rotating (using a special socket wrench) the input shaft (not shown) of the worm gear, driving the rotation of the output shaft 25, which, winding the fishing line 28 around itself, pulls it and rotates lever 26 around axis 27. Lever 26 pushes spool 17 through stop 19. Control of installation of spool 17 to its original position is visual, through radial holes 30 in cylinder 16 of the quick-release cartridge.

Head 3 serves to ensure the tightness of the quick-release cartridge 2 before operation and is equipped with a sealed fixed contact 31 (see Fig. 1).

Assembling the device.

A collet 5 is installed in the adapter 7, the petals 6 of the collet 5 are snapped into the bore 13 of the adapter 7. Then a piston-clamp 9 is installed in the collet 5 with the upper 10 and lower 11 contacts installed in it, connected into an electrical line by wire 12. Then they screw it onto the collet 5 housing 4. Install the drive of the separation mechanism (quick-release cartridge) 2; for this, the cylinder 16 of the quick-release cartridge is inserted into hole 29 of the housing 4. The head 3 is screwed onto the housing 4 with the quick-release cartridge 2 installed in it.

The installation of an electric downhole disconnector into the assembly is carried out by screwing, like all elements of the assembly. The layout is approved by the work plan for carrying out perforation and blasting operations at the well. The electrical downhole disconnector is installed in the instrument part of the assembly, i.e. above the sections of the hammer drill (by screwing) in order to, for example, in case of an emergency, disconnect and lift the instrument part, to eliminate the risk of separation or damage to the geophysical cable). The location of the ERA in the layout is determined by the work plan; Fig. 5 shows an example of a possible location of the ERA in the layout.

After each activation of the ERA, the sealing rings, contacts 10, 11, and shear pins 14 are replaced in the disconnection mechanism 1; in head 3 there is a sealed contact 31. Quick-release cartridge 2 cannot be restored.

Device operation.

When the arrangement reaches the perforated interval, ERA ensures transit of the control electrical signal from cable 33 (see Fig. 5) and higher-level components of the arrangement through transit wire 12 connected along the chain: sealed contact 31 of head 3 - upper spring-loaded contact 20 of quick-release cartridge 2 - addressable key 23 - lower spring-loaded contact 21 of the quick-release cartridge 2 - upper sealed contact 10 of the locking piston 9 - transit wire 12 - lower contact 11 of the locking piston 9. Control of the release mechanism 1 using an electrical signal allows for a reduction in the time for its operation and, as a result, to disconnect the assembly, which reduces the time for lifting a stuck assembly and prevents the creation of an emergency situation.

The release of the spool 17 is carried out by burning the line 28 with an electric igniter 22, which is started by the address key 23 by a signal from the surface when an emergency situation occurs. When unlocked, the spool 17 is pushed up by the spring 18 and after the lower sealing ring 34 of the spool 17 leaves the sealing surface of the cylinder 16, the well fluid through the radial holes 35 in the housing 4 of the release mechanism 1 and the radial holes 30 and the axial 36 holes in the cylinder 16 enters the working cavity 37 release mechanism 1 (see Fig. 4). Making the release mechanism drive from simple interconnected elements reduces the time required to disconnect the assembly and, as a consequence, reduces the time for lifting a stuck assembly and prevents the creation of an emergency situation.

As an option for the spool fixation device, it can be released using a spindle nut driven by a microelectric motor with a gearbox and a lead screw, which is started from a direct current source included in the cartridge when a separate electrical circuit is closed. The circuit closes a relay, which is activated by address key 23 by a signal from the surface (this option is not shown in the diagrams above).

The force from the increased pressure sets the piston-clamp 9 in motion. The locking piston 9 cuts off the pins 14, releases the petals 6 of the collet 5, rests against the adapter 7 and pushes the collet 5 with the removable part of the assembly from the socket of the adapter 7. The O-rings 38 of the collet 5 come out of mate with the adapter 7, thereby violating the tightness of the sub-piston space and finally disconnecting the layout. After lifting the retrievable part of the assembly, the remaining part can be removed from the outer part of the adapter 7 using an overshot with a suitable diameter lowered onto the tubing.

The claimed invention can be manufactured on modern equipment using known materials, elements and modern technologies.

The claimed invention can be used in the oil and gas industry when carrying out downhole operations when it is necessary to disconnect one piece of equipment from another.

Claims (5)

1. An electric downhole disconnector containing a head with a disconnection mechanism placed in it, consisting of an adapter and a housing with a collet installed in it, having a piston-clamp and connected to the adapter, and a disconnection mechanism drive connected to the disconnection mechanism housing and including a housing with a cover , installed in it is a cylinder equipped with a spool and a spring, an upper spring-loaded contact installed in the cover, a lower spring-loaded contact installed in the cylinder, and a spool fixation device. 2. The disconnector according to claim 1, characterized in that the head is made in the form of a hollow body and is equipped with a sealed fixed contact. 3. The disconnector according to claim 1, characterized in that the piston-clamp is equipped with contacts installed into it on opposite sides and connected into an electrical line. 4. The disconnector according to claim 1, characterized in that the spool fixing device contains a worm gear with an output shaft, a lever swinging on an axis fixed in the drive housing of the disconnection mechanism, a fishing line fixed at one end to the lever and the other to the output shaft of the worm gear and emphasis. 5. The disconnector according to claim 1, characterized in that the spool fixation device is made of a lead nut, a micro-electric motor connected to a direct current source and equipped with a gearbox, a lead screw and a relay.