CN209990451U

CN209990451U - Pipe column expansion compensator

Info

Publication number: CN209990451U
Application number: CN201920806138.9U
Authority: CN
Inventors: 王吉忠; 王昌彬; 吴小娟
Original assignee: JIANGSU LIKE PETROLEUM MACHINERY Co Ltd
Current assignee: JIANGSU LIKE PETROLEUM MACHINERY Co Ltd
Priority date: 2019-05-31
Filing date: 2019-05-31
Publication date: 2020-01-24
Anticipated expiration: 2029-05-31

Abstract

The utility model discloses a tubular column compensator that stretches out and draws back, including top connection and lower clutch the top connection in-connection has the center tube, and the sealing cover has the outer tube in this center tube periphery can be followed the axial activity ground, and the lower extreme and the lower clutch of outer tube are connected, are equipped with cyclic annular piston between outer tube hole and lower clutch excircle, and cyclic annular piston passes through shear pin and links to each other with the lower clutch, and it has the fixture block that can follow radial activity to peg graft on the lateral wall of lower clutch upper end, and the inboard joint of fixture block is equipped with the inclined plane in the draw-in groove of center tube lower extreme on the inboard lower terminal surface of fixture block, and the outside of fixture block is spacing. Adopt the utility model discloses a tubular column compensator that stretches out and draws back can compensate tubular column length variation, improves the atress situation of downhole tools such as packers, guarantees the normal work of oil well.

Description

Pipe column expansion compensator

Technical Field

The utility model relates to an oil field instrument in the pit especially relates to a telescopic tubular column length compensation arrangement.

Background

In an oil production well, a downhole string is provided with downhole tools such as packers and the like to extend from the ground to an oil layer with a depth of thousands of meters below the ground surface, so as to realize the production of oil. The working length of the underground pipe column is more than kilometer and is influenced by underground pressure and temperature change, the large expansion change of the pipe column length often occurs in the working process, particularly the water injection pipe column has large working temperature change and obvious expansion change, the expansion change of the pipe column inevitably brings additional axial acting force to underground tools such as a packer and the like fixedly connected with an underground casing in a sealing way, the working performance and the service life of the underground tools are influenced or the displacement of the packer is possibly caused, and for the pipe column, the pipe column between the packers inevitably generates axial stress due to thermal elongation and causes bending deformation of the pipe column, which is extremely unfavorable for the normal working of an oil well.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a telescopic compensator for a pipe column is provided, which can compensate the length change of the pipe column, improve the stress condition of downhole tools such as a packer and the like, and ensure the normal work of an oil well.

In order to solve the technical problem, the utility model discloses a tubular column compensator that stretches out and draws back, including top connection and lower clutch the top connection in-connection has the center tube, and it has the outer tube to seal the cover in this center tube periphery can follow the axial activity ground seal cover, and the lower extreme and the lower clutch of outer tube are connected, are equipped with annular piston between outer tube hole and lower clutch excircle, and annular piston passes through shear pin and links to each other with the lower clutch, and it has the fixture block that can follow radial activity to peg graft on the lateral wall of lower clutch upper end, and the inboard joint of fixture block is equipped with the inclined plane in the draw-in groove of center tube lower extreme on the inboard lower terminal surface of fixture block, and the outside of.

In the structure, because the center tube is connected in the upper joint, the outer sleeve is movably sleeved on the periphery of the center tube in the axial direction, the lower end of the outer sleeve is connected with the lower joint, relative axial movement can be generated between the upper joint and the lower joint through the outer sleeve and the center tube, the telescopic change of the underground pipe column can be adapted, the outer sleeve and the center tube are connected in a sealing manner, the connection between the inner cavity of the center tube and the outer cavity of the center tube can be ensured, and the normal production operation of an oil well can not be influenced.

And because the annular piston is arranged between the inner hole of the outer sleeve and the excircle of the lower joint, the annular piston is connected with the lower joint through the shear pin, the side wall of the upper end of the lower joint is inserted with the clamping block which can move along the radial direction, the inner side of the clamping block is clamped in the clamping groove at the lower end of the central tube, the lower end surface of the inner side of the clamping block is provided with the inclined surface, the outer side of the clamping block is limited in the inner hole at the upper end of the annular piston, the clamping block limited in the inner hole of the annular piston ensures that the lower joint and the central tube limit the mutual position and cannot generate the mutual axial movement, thereby being capable of smoothly descending into an oil well with fixed length, after a tubular column is put in place, the oil pipe is pressed from the inside, the hydraulic pressure acts on the upper end surface of the annular piston from the gap between the upper joint and the lower joint, the connection between the annular piston and the lower joint is cut, the annular piston does not play a role in limiting the clamping block any more, hydraulic pressure acts on the lower joint through the annular piston, the lower joint can generate a trend of driving the clamping block to move downwards, due to the existence of the inclined plane arranged on the lower end surface of the inner side of the clamping block, a clamping groove part on the central tube, which is in contact with the clamping block, can generate a radial acting force on the inclined plane on the lower end surface of the clamping block, so that the clamping block moves along the radial direction of the lower joint and is separated from the central tube, the position limitation between the central tube and the lower joint disappears, and relative axial displacement can be generated between the lower joint and the central tube, so that the upper joint and the lower joint can generate relative axial movement through the outer sleeve and the central tube in a free state, the expansion change generated by the underground pressure and temperature change of the underground pipe column is compensated, and the accidental stress generated by the underground pipe column on underground tools such as a packer and the like due to, the stress condition of the underground tools is improved, and the normal work of the oil well is ensured.

The utility model discloses a preferred embodiment the lower terminal surface of draw-in groove has the inclined plane corresponding with the inboard lower terminal surface of fixture block. By adopting the embodiment, the lower end surface of the clamping groove can form good surface contact with the lower end surface of the inner side of the clamping block, so that the clamping block can move smoothly along the radial direction of the lower joint and can be conveniently separated from the upper joint.

The utility model discloses a another kind of preferred embodiment the center tube lower extreme is equipped with the connecting seat cover, the draw-in groove sets up on this connecting seat cover. By adopting the embodiment, the lower end of the central tube is of a split structure, so that the central tube can be conveniently manufactured and processed.

In another preferred embodiment of the present invention, the upper end of the connecting seat cover is screwed with the central tube and is fixedly connected with the central tube by a set screw. By adopting the embodiment, the connection between the connecting seat sleeve and the central pipe is convenient and reliable.

The utility model discloses further preferred embodiment, the outer tube upper end is through last adapter sleeve seal cup joint on the center tube, goes up the adapter sleeve and connects soon in the outer tube, goes up between adapter sleeve hole and the center tube excircle and all is equipped with the sealing washer between upper adapter sleeve and the outer tube inner hole. By adopting the embodiment, the outer sleeve can be conveniently manufactured, and the axial movement of the outer sleeve can be limited by the lower end surface of the connecting sleeve and the step at the lower end of the central tube.

The utility model discloses another further preferred embodiment, the outer tube lower extreme connects on the lower clutch through lower adapter sleeve soon, and lower adapter sleeve connects in the outer tube soon, and lower adapter sleeve up end is greater than interval B between the terminal surface under cyclic annular piston up end to the fixture block under to cyclic annular piston interval A between the terminal surface. By adopting the embodiment, the processing of the inner hole of the outer sleeve can be facilitated, the matching precision between the inner hole of the outer sleeve and the annular piston is ensured, and the distance A is larger than the distance B, so that the annular piston can be enabled to be separated from the limiting position of the clamping block in the stroke of the annular piston.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Fig. 1 is a schematic structural diagram of a specific embodiment of the telescopic compensator of the utility model.

In the figure: 1-upper joint, 2-central tube, 3-upper connecting sleeve, 4-sealing ring, 5-outer sleeve, 6-connecting seat sleeve, 7-clamping groove, 8-clamping block, 9-inclined plane, 10-annular piston, 11-shear pin, 12-lower connecting sleeve and 13-lower joint.

Detailed Description

In the pipe string telescopic compensator shown in fig. 1, an upper joint 1 and a lower joint 13 are connecting pieces connected with an oil well inner pipe string, the upper end of an inner hole of the upper joint 1 is provided with a thread connected with the upper pipe string, and a central pipe 2 is fixedly connected below the upper joint 1 through the thread at the lower end of the inner hole; an outer sleeve 5 is movably sleeved on the periphery of the central tube 2 in an axial direction in a sealing manner, as a preferred scheme, the upper end of the outer sleeve 5 is sleeved on the central tube 2 in a sealing manner through an upper connecting sleeve 3, the upper connecting sleeve 3 is screwed in the outer sleeve 5, and O-shaped sealing rings 4 are arranged between an inner hole of the upper connecting sleeve 3 and the outer circle of the central tube 2 and between the outer circle of the upper connecting sleeve 3 and the inner hole of the outer sleeve 5; the lower end of the outer sleeve 5 is connected with a lower joint 13, the lower end of an inner hole of the lower joint 13 is provided with a thread connected with a pipe column at the lower part, as a preferred scheme, the lower end of the outer sleeve 5 is screwed on the lower joint 13 through a lower connecting sleeve 12, and the lower connecting sleeve 12 is screwed and fixedly connected in the outer sleeve 5 and fixedly connected through a set screw; an annular piston 10 is arranged between the inner hole of the outer sleeve 5 and the excircle of the lower joint 13; two to four fixture block insertion holes are uniformly distributed on the side wall of the upper end of the lower joint 13 along the circumferential direction, a fixture block 8 capable of moving along the radial direction is inserted in each fixture block insertion hole, the inner side of the fixture block 8 is clamped in a clamping groove 7 at the lower end of the central tube 2, as a preferred scheme, a connecting seat sleeve 6 is arranged at the lower end of the central tube 2, the upper end of the connecting seat sleeve 6 is screwed with the central tube 2 and is fixedly connected with the central tube through a set screw, the clamping groove 7 is arranged on the connecting seat sleeve 6, an inclined plane 9 is arranged on the lower end surface of the inner side of the fixture block 8, and an inclined plane corresponding to the lower end; before descending the well, the annular piston 10 is connected with the lower joint 13 through the shear pin 11, so that the outer side of the clamping block 8 is limited in the inner hole at the upper end of the annular piston 10, the distance A between the upper end surface of the lower connecting sleeve 12 and the lower end surface of the annular piston 10 is larger than the distance B between the upper end surface of the annular piston 10 and the lower end surface of the clamping block 8, and the lower joint 13 is connected with the upper joint 1 through the clamping block 8 and the central pipe 2 to form a relatively fixed whole.

After the well is lowered, the pressure is applied from the inside of the oil pipe, the hydraulic pressure enters from the gap between the upper joint 1 and the connecting seat sleeve 6 as well as the lower joint 13 and acts on the upper end surface of the annular piston 10, so that the connection between the annular piston 10 and the lower joint 13 is cut off by the shear pin 11, the annular piston 10 is pushed to move downwards, when the annular piston 10 moves downwards to be separated from the fixture block 8, the annular piston 10 does not play a limiting role on the fixture block 8 any more, the hydraulic pressure acts on the lower joint 13 through the annular piston 10, the lower joint 13 generates a trend of driving the fixture block 8 to move downwards, due to the existence of the inclined surface 9 arranged on the lower end surface inside the fixture block 8, the part of the clamping groove 7 on the central pipe 2, which is in contact with the fixture block 8, generates a radial component acting force on the inclined surface 9 on the lower end surface of the fixture block 8, so that the fixture block 8 moves radially, the position restriction between the central tube 2 and the lower joint 13 disappears, and the lower joint 13 and the central tube 2 can generate relative axial displacement, so that the upper joint 1 and the lower joint 13 are in a free state and can generate relative axial movement through the outer sleeve 5 and the central tube 2, the expansion change caused by the influence of underground pressure and temperature change on an underground pipe column is compensated, the accidental stress on the underground tools such as a packer and the like caused by the expansion and contraction possibly generated by the underground pipe column is avoided, the stress condition of the underground tools is improved, and the normal work of an oil well is ensured.

The above description has been presented only for the purpose of illustrating certain preferred embodiments of the invention, and it is not to be taken as a limitation on the invention, as many modifications and variations are possible. If the side wall of the upper end of the lower joint 13 is not uniformly provided with two to four fixture block insertion holes along the circumferential direction, one or more than four fixture block insertion holes may be uniformly provided along the circumferential direction; an O-shaped sealing ring 4 can be arranged between the inner hole of the upper connecting sleeve 3 and the outer circle of the central tube 2, and a rectangular sealing ring or other sealing rings can be arranged between the inner hole of the upper connecting sleeve and the outer circle of the central tube. Therefore, any improvement and changes made on the basis of the basic principle of the present invention should be considered as falling within the protection scope of the present invention.

Claims

1. The utility model provides a telescopic compensator for pipe column, includes top connection (1) and lower clutch (13), its characterized in that: the outer sleeve is connected with the outer sleeve (5) in the upper joint (1) in a sealing mode, the outer periphery of the outer sleeve (2) can be movably sleeved with the outer sleeve (5) in the axial direction, the lower end of the outer sleeve (5) is connected with the lower joint (13), an annular piston (10) is arranged between an inner hole of the outer sleeve (5) and the outer circle of the lower joint (13), the annular piston (10) is connected with the lower joint (13) through a shear pin (11), a clamping block (8) capable of moving along the radial direction is inserted into the side wall of the upper end of the lower joint (13), the inner side of the clamping block (8) is clamped in a clamping groove (7) in the lower end of the central tube (2), an inclined plane (9) is arranged on the lower end face of the inner side of the clamping block (8).

2. The pipe string telescopic compensator of claim 1, wherein: the lower end face of the clamping groove (7) is provided with an inclined plane corresponding to the lower end face of the inner side of the clamping block (8).

3. The pipe string telescopic compensator of claim 1 or 2, wherein: the lower end of the central pipe (2) is provided with a connecting seat sleeve (6), and the clamping groove (7) is arranged on the connecting seat sleeve (6).

4. The pipe string telescopic compensator of claim 3, wherein: the upper end of the connecting seat sleeve (6) is screwed with the central pipe (2) and is fixedly connected with the central pipe through a set screw.

5. The pipe string telescopic compensator of claim 1, wherein: the upper end of the outer sleeve (5) is hermetically sleeved on the central pipe (2) through the upper connecting sleeve (3), the upper connecting sleeve (3) is connected in the outer sleeve (5) in a rotating mode, and the sealing rings (4) are arranged between the inner hole of the upper connecting sleeve (3) and the excircle of the central pipe (2) and between the upper connecting sleeve (3) and the inner hole of the outer sleeve (5).

6. The pipe string telescopic compensator of claim 1, wherein: the lower end of the outer sleeve (5) is connected to the lower joint (13) through the lower connecting sleeve (12) in a rotating mode, the lower connecting sleeve (12) is connected and fixed in the outer sleeve (5) in a rotating mode, and the distance A from the upper end face of the lower connecting sleeve (12) to the lower end face of the annular piston (10) is larger than the distance B from the upper end face of the annular piston (10) to the lower end face of the clamping block (8).