CN108505951B

CN108505951B - Locking device

Info

Publication number: CN108505951B
Application number: CN201710098683.2A
Authority: CN
Inventors: 李夯; 谷磊; 邵志香; 郑晓志; 张瑞; 刘明; 李鹏飞; 侯跃全; 邹传元
Original assignee: China Petroleum and Chemical Corp; Sinopec Research Institute of Petroleum Engineering
Current assignee: China Petroleum and Chemical Corp; Sinopec Research Institute of Petroleum Engineering
Priority date: 2017-02-23
Filing date: 2017-02-23
Publication date: 2020-07-03
Anticipated expiration: 2037-02-23
Also published as: CN108505951A

Abstract

The invention relates to a locking device, which comprises an outer pipe column, an inner pipe column sleeved on the inner side of the outer pipe column, and a movable block arranged between the outer pipe column and the inner pipe column, a fixed receiving groove for receiving the movable block is formed on one of the inner string and the outer string, a first receiving groove and a second receiving groove are configured on the other of the inner string and the outer string, wherein, in a first state, the first receiving groove is aligned opposite to the fixed receiving groove to enclose the movable block therein, the movable block can be in clamping fit with the first accommodating groove so as to prevent the inner pipe column and the outer pipe column from moving relatively in the axial direction, in a second state, the second receiving groove is aligned opposite to the fixed receiving groove to enclose the movable block therein, the movable block can be in sliding fit with the second accommodating groove to allow the inner pipe column and the outer pipe column to move relatively in the axial direction. The stability of this locking device is high.

Description

Locking device

Technical Field

The invention relates to the technical field of oil and gas well cementation construction, in particular to a locking device.

Background

During downhole operations, it is often necessary to provide a locking device in order to perform the operation. For example, in one state, the locking device may prevent relative movement of two of the components (e.g., inner and outer tubing strings) in a given direction, while in another state, the locking device may allow relative movement of the two components in a given direction. For example, for downhole releasing operations, this is typically accomplished by axial relative movement of the inner and outer tubular strings.

However, in the prior art, the locking means are usually realized by hydraulic techniques. This places high demands on the structural strength of the locking device itself, the precision of machining of the parts, the precision of assembly, etc. If the structure of the locking device is out of order and the high demand cannot be met, the locking device becomes unstable and is liable to be released from the locked state in an unexpected manner, allowing the inner and outer strings to be dislocated or even disengaged from each other, or being liable to be locked and not released from the locked state. This is a very serious problem for downhole operations and can seriously affect the performance of subsequent work.

Therefore, a locking device with high stability is required.

Disclosure of Invention

In view of the above problems, the present invention provides a locking device with high stability.

According to the present invention, there is provided a locking device comprising an outer tubular column, an inner tubular column fitted around an inner side of the outer tubular column, and a movable block disposed between the outer tubular column and the inner tubular column, a fixed receiving groove for receiving the movable block is formed on one of the inner string and the outer string, a first receiving groove and a second receiving groove are configured on the other of the inner string and the outer string, wherein, in a first state, the first receiving groove is aligned opposite to the fixed receiving groove to enclose the movable block therein, the movable block can be in clamping fit with the first accommodating groove so as to prevent the inner pipe column and the outer pipe column from moving relatively in the axial direction, in a second state, the second receiving groove is aligned opposite to the fixed receiving groove to enclose the movable block therein, the movable block can be in sliding fit with the second accommodating groove to allow the inner pipe column and the outer pipe column to move relatively in the axial direction.

Through above-mentioned locking device, can realize the locking or unblock (i.e. can relative movement) between outer tubular column and the inner tube post through the cooperation of movable block and first holding tank and second holding tank. The locking device of this arrangement can fulfil its function by a simple fit and therefore the assembly of the individual components themselves and between the individual components does not have to be of a very strict level of precision. Thus, the locking device has high stability in operation, and can be operated at a specific timing according to the needs of the user to smoothly realize the function thereof.

In one embodiment, the first receiving groove and the second receiving groove are circumferentially arranged, and the first state to the second state is enabled by relative rotation between the outer tubular string and the inner tubular string.

In one embodiment, the first receiving groove and the second receiving groove are circumferentially spaced apart from each other.

In one embodiment, an elastic member is disposed between the movable block and the bottom surface of the fixed receiving groove.

In one embodiment, the first side of the movable block is configured with a side sliding ramp that is capable of sliding engagement with a corresponding side of the first receiving groove.

In one embodiment, the first side of the movable block is further configured with a side clamping portion capable of being clamped and matched with the corresponding side of the second accommodating groove, the side clamping portion is closer to the bottom surface of the fixed accommodating groove relative to the side sliding inclined surface, and the corresponding side of the second accommodating groove is deeper than the corresponding side of the first accommodating groove.

In one embodiment, the upstream end of the movable block is configured with an upstream sliding ramp that is capable of sliding engagement with the upstream end of the second receiving groove, and/or the upstream end of the second receiving groove is configured with an upstream guiding ramp that is capable of sliding engagement with the upstream end of the movable block.

In one embodiment, the locking device is further configured with a release mechanism that locks in a first state and enables release in a second state.

In one embodiment, the axial length of the first receiving groove is smaller than the axial length of the second receiving groove, the receiving groove can slide in the second receiving groove along the axial direction, and in the second state, the releasing mechanism responds to the movable block sliding in the second receiving groove to realize releasing.

In one embodiment, the upstream end of the first receiving groove is aligned with the upstream end of the second receiving groove, the downstream end of the second receiving groove extends further downstream relative to the downstream end of the first receiving groove, and in the second state, the release mechanism effects release in response to the movable block sliding axially downstream within the receiving groove.

Compared with the prior art, the invention has the advantages that: through above-mentioned locking device, can realize the locking or unblock (i.e. can relative movement) between outer tubular column and the inner tube post through the cooperation of movable block and first holding tank and second holding tank. The locking device of this arrangement can fulfil its function by a simple fit and therefore the assembly of the individual components themselves and between the individual components does not have to be of a very strict level of precision. Thus, the locking device has high stability in operation, and can be operated at a specific timing according to the needs of the user to smoothly realize the function thereof.

Drawings

The invention will be described in more detail hereinafter on the basis of embodiments and with reference to the accompanying drawings. Wherein:

FIG. 1 is a schematic structural view of one embodiment of a locking device according to the present invention in one state;

FIG. 2 is a schematic view of the locking device of FIG. 1 in another configuration;

FIG. 3 is a cross-sectional schematic view of the locking device of FIG. 1;

fig. 4 is a schematic cross-sectional view of the locking device of fig. 2.

In the drawings, like parts are provided with like reference numerals. The drawings are not to scale.

Detailed Description

The invention will be further explained with reference to the drawings.

Fig. 1 and 2 schematically show an embodiment of a locking device 1 according to the invention.

The locking device 1 comprises an inner string 10 and an outer string 20, the inner string 10 being sleeved on the inner side of the outer string 20. The locking device 1 has two states, a first state and a second state. In the first state, the inner string 10 and the outer string 20 are locked and thus cannot be moved relative to each other in the axial direction. In the second state, the inner string 10 and the outer string 20 are unlocked and can thus be moved relative to each other in the axial direction.

In order to achieve the above-described first state and second state, the lock device 1 is configured as follows.

The locking device 1 includes a movable block 30, a fixed receiving groove 11, a first receiving groove 21, and a second receiving groove 22. In the first state, as shown in fig. 1, the fixed receiving groove 11 is aligned with the opening of the first receiving groove 21 to surround and form a receiving cavity, and the movable block 30 is received in the receiving cavity and is in snap fit with the first receiving groove 21 in the axial direction, so that the inner string 10 and the outer string 20 are fixed in the axial direction. Preferably, the upstream and downstream ends of the first receiving groove 21 are snap-fitted with the movable block 30, so that the inner string 10 and the outer string 20 are axially fixed, whether the inner string 10 is lifted up or lowered down.

In the second state, as shown in fig. 2, the fixed receiving groove 11 is aligned opposite to the opening of the second receiving groove 22 to surround and form a receiving cavity, and the movable block 30 is received in the receiving cavity and slidably engaged with the second receiving groove 22 in the axial direction to enable the inner string 10 and the outer string 20 to relatively move in the axial direction.

In one embodiment, the upstream end of the movable block 30 may be configured with an upstream sliding ramp that slidingly engages the upstream end of the second receiving slot 22. Additionally or alternatively, the upstream end of the second receiving groove 22 may be configured with an upstream guide ramp that is a sliding fit with the upstream end of the movable block 30. It should be understood that, instead of providing a guide slope or the like at the upstream end of the first receiving groove 22, a structure that blocks the movable block 30 from moving in the axial direction may be provided.

It should be understood that the movable block 30 itself may have a certain elasticity to achieve the respective fitting with the first receiving groove 21 and the second receiving groove 22. Preferably, an elastic member 40, such as a coil spring, is provided between the movable block 30 and the bottom surface of the fixing receiving groove 11. In this case, the movable block 30 itself is rigid to ensure stability in its engagement with the first receiving groove 21 and the second receiving groove 22.

In the case where the elastic member 40 is provided, when the movable block 30 can be abutted against the bottom walls of the first receiving groove 21 and the second receiving groove 22, respectively, sufficient engagement of the movable block 30 with the first receiving groove 21 and the second receiving groove 22 is achieved. In this case, the upstream end of the movable block 30 is preferably configured with an upstream catching portion (e.g., a flat surface extending in the radial direction) that can catch-engage with the upstream end of the first receiving groove 21, the upstream catching portion being closer to the fixed receiving groove 11 than to the upstream sliding slope. In addition, the upstream end of the first accommodation groove 21 is deeper than the upstream end of the second accommodation groove. Thus, when the movable block 30 is located in the first receiving groove 21, the upstream sliding slope thereof can be engaged with the upstream end of the first receiving groove 21. And when the movable block 30 is located in the second receiving groove 22, the movable block 30 will extend into the second receiving groove 22 more, so that the upstream clamping portion thereof is matched with the upstream end of the second receiving groove 22.

In a preferred embodiment, the elastic member 40 connects the movable block 30 with the fixing receiving groove 11. This ensures that the movable block 30 is always located in the stationary accommodating groove 11, thereby improving the stability of the locking device 1. In addition, after the inner pipe string 10 is separated from the outer pipe string 20, the movable block 30 can be lifted up together with the inner pipe string 10 to be recovered.

Preferably, as shown in fig. 3 and 4, the first receiving grooves 21 and the second receiving grooves 22 are arranged in the circumferential direction. Accordingly, the movable block 30 can be inserted from the first receiving groove 21 into the second receiving groove 22 by rotating the inner string 10 with respect to the outer string 20, thereby achieving the first state to the second state.

The first receiving groove 21 and the second receiving groove 22 may be disposed adjacent to each other so as to communicate with each other, or may be disposed at intervals as shown in fig. 3 and 4.

In addition, as shown in fig. 3 and 4, the first side of the movable block 30 may be configured with a side sliding slope 31, and the side sliding slope 31 can be slidably engaged with the corresponding side of the first receiving groove 21. Additionally or alternatively, the corresponding side of the first receiving groove 21 is provided with a side guide slope 211 for sliding engagement with the first side of the movable block 30. Thus, in the embodiment shown in fig. 3, when the inner string 10 is rotated counterclockwise with respect to the outer string 20, the movable block 30 can easily leave the first receiving groove 21 and enter the second receiving groove. It should be understood that the corresponding side of the second receiving groove 22, the other side of the second receiving groove 22, and the other side of the first receiving groove 21 are not provided with the side guide slope or the like, but may be provided with other structures that promote the snap-fit engagement with the movable block 30. Thus, when the inner string 10 is rotated in the clockwise direction, the outer string 20 is rotated together with the inner string 10. This arrangement allows the string (string) to be rotated to improve cement slurry displacement efficiency as it is run into the well and to be rotated to unblock the string.

Preferably, as shown in fig. 2, the first side of the movable block 30 is further configured with a side clamping portion 32 capable of clamping-fitting with a corresponding side of the second receiving groove 22, and the side clamping portion 32 is closer to the bottom surface of the fixing receiving groove 11 than the side sliding slope 31. The corresponding side of the second receiving groove 22 is made deeper than the corresponding side of the first receiving groove. Thus, when the movable block 30 is in the first receiving groove 21, the side sliding inclined surface 31 thereof can be slidably engaged with the corresponding side of the first receiving groove 21. When the movable block 30 is located in the second receiving groove 22, the side clamping portion 32 can be clamped and matched with the corresponding side of the second receiving groove 22.

The locking device 1 can be made in such a structure: the axial length of the first receiving groove 21 is set to just receive the movable block 30, so that when the movable block 30 is in the first receiving groove 21, it cannot slide axially in the first receiving groove 21, thereby preventing the inner string 10 from moving in the axial direction relative to the outer string 20; meanwhile, the axial length of the second receiving groove 21 is longer than the axial length of the first receiving groove 21, so that when the movable block 30 is in the second receiving groove 22, it can slide in the axial direction in the second receiving groove 22, thereby allowing the inner tubular string 10 to move in the axial direction relative to the outer tubular string 20.

In the embodiment shown in fig. 1 and 2, the upstream ends of the first receiving groove 21 and the second receiving groove 22 are aligned, and the downstream end of the second receiving groove 22 extends further downstream with respect to the downstream end of the first receiving groove 21. Thus, after the movable block 30 enters the second receiving groove 22, the inner string 10 can move downstream relative to the outer string 20.

This is particularly advantageous, for example, when the locking device 1 comprises a release mechanism that is actuated by the inner string 10 moving downwards relative to the outer string 20 to release the release.

As shown in fig. 1, the release mechanism includes a sliding sleeve 50 sleeved between the inner string 10 and the outer string 20, and jaws 60 extending downstream from the sliding sleeve 50. At this time, the inner and

outer columns

10 and 20 and the sliding sleeve 50 are fixed in the axial direction. Thereby, in the first state, the catch 60 is pushed by the inner string 10 into the recess 23 of the outer string. In this case, the force can be transmitted to the outer string 20 by the dogs 60, whether the inner string 10 is lifted up or the inner string 10 is lowered down, to further ensure that the inner string 10 is fixed in the axial direction with the outer string 20 and to achieve that the outer string 20 moves with the inner string 10. In addition, a snap spring 70 is further sleeved between the sliding sleeve 50 and the inner tubular column 10, and the snap spring 70 is fixed in the axial direction relative to the sliding sleeve 50. The latch spring 70 is not latched into the positioning groove of the inner string 10 in the first state.

In the second state, the inner string 10 moves downstream to no longer abut against the claws 60, and the circlip 70 can enter the positioning groove of the inner string 10 as the inner string 10 moves. At this time, the sliding sleeve 50 and the jaws 60 are fixed relative to the inner tubular string 10. The inner string 10 is then lifted up, i.e. the sliding sleeve 50 and the dogs 60 are lifted up simultaneously, leaving the dogs 60 clear of the recesses 23 on the outer string 20, thereby effecting a release.

It will be appreciated that during lifting of the inner tubular string 10, the movable block 30 may be moved away from the second receiving slot 22 by the sliding engagement of the upstream end of the movable block 30 with the upstream end of the second receiving slot 22, thereby completely separating the inner tubular string 10 from the outer tubular string 20.

It will also be appreciated that the release mechanism could be constructed in any other suitable configuration, or that the locking device 1 could be provided with other cooperating structures.

Further, if necessary, the fixing housing groove 11 may be provided on the outer column 20, and the first housing groove 21 and the second housing groove 22 may be provided on the inner column 10.

The operation of the locking device 1 will be described in detail below.

The locking device 1 is in the first state when it is run into the well. As shown in fig. 1, at this time, the movable block 30 is located in the first receiving groove 21 and is in snap fit with the first receiving groove 21 in the axial direction, so that the inner string 10 and the outer string 20 are fixed in the axial direction. With the release mechanism provided, the dogs 60 are abutted by the inner string 10 into the recesses 23 of the outer string 20 to further axially lock the inner string 10 with the outer string 20. During run in, the inner tubular string 10 may be rotated clockwise (based on the configuration shown in FIG. 3) to facilitate the run in process.

After the locking device 1 is lowered to a predetermined position, the movable block 30 is moved from the first receiving groove 21 into the second receiving groove 22 by rotating the inner pipe 10 counterclockwise. The inner string 10 is now lowered, allowing the inner string 10 to move downstream relative to the outer string. At this point, the inner string 10 no longer abuts the dogs 60 within the recesses 23 of the outer string 20. Then, when the inner tubular string 10 is lifted up, the dogs 60 will disengage from the recesses 23. Further lifting the inner tubular column 10 can disengage the movable block 30 from the second receiving groove 22. Thereby, a complete separation of the inner string 10 from the outer string 20 is achieved.

While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. It is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. A locking device comprises an outer pipe column, an inner pipe column sleeved on the inner side of the outer pipe column, and a movable block arranged between the outer pipe column and the inner pipe column,

a fixed receiving groove configured to receive the movable block is formed on one of the inner and outer strings, a first receiving groove and a second receiving groove are configured on the other of the inner and outer strings,

wherein in a first state the first receiving groove is aligned relative to a fixed receiving groove to enclose the movable block therein, the first receiving groove having an axial length configured to snugly receive the movable block such that the movable block cannot slide axially within the first receiving groove to prevent relative movement of the inner and outer tubular strings in an axial direction,

in a second state, the second receiving groove is aligned opposite to the fixed receiving groove to enclose the movable block therein, and an axial length of the second receiving groove is greater than an axial length of the first receiving groove, so that the movable block can slide axially within the second receiving groove to allow the inner string and the outer string to move relatively in an axial direction.

2. The locking device of claim 1, wherein the first and second receiving slots are circumferentially arranged to enable relative rotation between the outer and inner tubular strings from a first state to a second state.

3. The locking device of claim 2, wherein the first and second receiving grooves are circumferentially spaced from one another.

4. The locking device according to any one of claims 1 to 3, wherein an elastic member is provided between the movable block and a bottom surface of the stationary receiving groove.

5. A locking device according to any one of claims 1 to 3, wherein the first side of the movable block is configured with a side sliding ramp which is slidably engageable with a corresponding side of the first receiving slot.

6. The locking device of claim 5, wherein the first side of the movable block is further configured with a side engaging portion capable of engaging with a corresponding side of the second receiving groove, the side engaging portion is closer to the bottom surface of the fixed receiving groove than the side sliding slope,

wherein a corresponding side of the second receiving groove is deeper than a corresponding side of the first receiving groove.

7. A locking arrangement according to any one of claims 1 to 3, wherein the upstream end of the movable block is configured with an upstream sliding ramp which is slidably engageable with the upstream end of the second receiving groove, and/or

The upstream end of the second receiving groove is configured with an upstream guide slope that is in sliding engagement with the upstream end of the movable block.

8. The locking device according to any one of claims 1 to 3, characterized in that it is further configured with a release mechanism which locks in a first state and effects release in a second state.

9. The locking device of claim 8, wherein in the second state, the release mechanism effects release in response to the movable block sliding within the second receiving slot.

10. The locking device of claim 9, wherein an upstream end of the first receiving slot is aligned with an upstream end of the second receiving slot, a downstream end of the second receiving slot extends further downstream relative to the downstream end of the first receiving slot,

in the second state, the releasing mechanism responds to the movable block sliding downstream in the containing groove along the axial direction to realize releasing.