CN-121993069-A - Sealed core-supplementing releasing mechanism, tail pipe hanger and releasing method

CN121993069ACN 121993069 ACN121993069 ACN 121993069ACN-121993069-A

Abstract

The invention provides a sealing core-supplementing releasing mechanism, a tail pipe hanger and a releasing method, wherein the sealing core-supplementing releasing mechanism comprises a sealing elastic claw, a limiting sleeve and a cone body, the cone body is communicated with the hanger body, an insertion pipe is positioned between the cone body and the hanger body, and an annular space exists between the insertion pipe and the cone body and between the insertion pipe and the hanger body; the liquid conveying hole is formed in the insertion tube, the sealing elastic claw is sleeved on the insertion tube and is of an annular structure and provided with certain elasticity, an annular groove is formed in the inner wall of the cone body, the sealing elastic claw is located in the annular groove, the limiting sleeve is located at the upper end of the sealing elastic claw, the diameter reducing section is arranged on the insertion tube, and when the diameter reducing section reaches the position of the sealing elastic claw, the sealing elastic claw contracts towards the insertion tube under the action of self elasticity and is separated from the annular groove. The liner hanger comprises the sealing core-supplementing releasing mechanism. The release method is implemented using the liner hanger described above. The invention has the advantage of reducing the operation risk.

Inventors

SHI YAOWEI
WANG JUAN
XIAO YONG
XIAN YONG
PAN ZHIQIANG
BIN GUOCHENG
YU XIN
JIA BIAO
ZENG RONG
ZOU XIANGFU

Assignees

中国石油天然气集团有限公司
中国石油集团川庆钻探工程有限公司

Dates

Publication Date: 20260508
Application Date: 20241104

Claims (10)

1. The sealing core-supplementing releasing mechanism is characterized by comprising a sealing spring claw, a limiting sleeve and a cone body, wherein, The cone body is communicated with the hanger body, the insertion tube is positioned between the cone body and the hanger body, and annular spaces exist among the insertion tube, the cone body and the hanger body; the insertion pipe is provided with a liquid transmission hole through which drilling liquid can pass from the annular space to the insertion pipe; the sealing elastic claw is sleeved on the insertion tube, is of an annular structure and has certain elasticity; The inner wall of the cone body is circumferentially and uniformly provided with discontinuous annular grooves, and the sealing elastic claws are positioned in the annular grooves; the limiting sleeve is positioned at the upper end of the sealing elastic claw, and limits the sealing elastic claw to be stressed upwards during construction; the diameter-reducing section is arranged on the insertion tube, and when the diameter-reducing section reaches the position of the sealing elastic claw, the sealing elastic claw contracts towards the insertion tube under the action of self elasticity and is separated from the annular groove.
2. The seal core-compensating releasing mechanism as claimed in claim 1, wherein the upper end of the annular groove is provided with a conical surface chamfer structure, and the lower end is provided with a flat step.
3. The sealed core-compensating releasing mechanism as claimed in claim 1, wherein the lower end of the diameter-reducing section of the insertion tube is provided with a safety joint.
4. A sealed core-compensating release mechanism according to claim 3, wherein the safety joint is connected to the insertion tube by a shear pin.
5. The sealed core-compensating releasing mechanism of claim 1, wherein the bottom end of the insertion tube is provided with a tail tube rubber plug.
6. The seal cartridge release mechanism of claim 1, wherein a radial distance between the seal fingers and the reduced diameter section is greater than a depth of the annular groove.
7. The sealed core-compensating release mechanism of claim 1, wherein the surface of the insertion tube is treated with a teflon process.
8. A full-diameter liner hanger is characterized by comprising an inner layer structure and an outer layer structure, wherein, The inner layer structure comprises a feeding mechanism and a sealing core-supplementing releasing mechanism which are sequentially connected from top to bottom; the outer layer structure comprises a tieback mechanism and a sitting and hanging mechanism which are sequentially connected from top to bottom.
9. A method of releasing, wherein the method of releasing is achieved by the full-diameter hanger of claim 8, and the method of releasing comprises the steps of: when the diameter-reduced section of the insertion tube is up to the position of the sealing elastic claw, the sealing elastic claw is elastically contracted by the sealing elastic claw to separate from the annular groove of the cone body; if the sealing spring claw cannot shrink normally in the ascending process of the insertion tube, the insertion tube continues to ascend, the safety joint forcibly shrinks the spring claw, the annular groove is in forced fit with the sealing spring claw, and the power-assisted sealing spring claw shrinks to realize releasing.
10. The releasing method as claimed in claim 9, wherein if foreign matter is attached to the insertion tube during the upward movement, the insertion tube is rotated and the sealing spring claw scrapes off the attached matter.

Description

Sealed core-supplementing releasing mechanism, tail pipe hanger and releasing method Technical Field The invention relates to the technical field of underground tool manufacturing in the petroleum and natural gas industry, in particular to a sealing core-supplementing releasing mechanism, a tail pipe hanger and a releasing method. Background Liner cementing is an important means for cementing deep wells and complex wells. The liner hanger is a well cementing tool used in the well cementing process, the currently used liner hanger can keep parts of a sealing box and a sleeve rubber plug part inside the hanger after well cementing construction, after later drilling, cavity holding steps can appear inside the hanger to influence later operation, and long-time drilling and grinding inside the hanger can damage cementing quality between a cement sheath and a sleeve at the overlapping section of the hanger. The sealing box used in the conventional liner hanger is simple in structure and high in reliability, but the drilling and plugging period is increased, and residues possibly exist after drilling, so that the situation of the later-stage drift diameter is influenced. The full-drift-diameter scheme used at home and abroad mainly has the following technical defects that 1, a locking block-guide rail type sealing box adopted by the traditional tail pipe hanger has a complex structure, a required radial design space is large, and the performance is unstable when the full-drift-diameter scheme is used in an underground environment. 2. If there is a tiny pad attached in the gap between the locking block-guide rail type sealing box body and the insertion tube and between the sliding block and the sealing box body, the locking block may be blocked, so that the drilling difficulty is caused. 3. The sliding block containing cavity of the liner hanger body and the sealing box is an annular groove, the sliding block is not limited in the circumferential direction, and if a sealing core is repaired because of abnormal well retention, the subsequent drilling and grinding treatment is difficult. Therefore, it is necessary to design a liner hanger and a releasing method capable of overcoming the above problems and realizing a full-diameter liner. The Chinese patent with the publication number of CN102587852A, named as a liner hanger and a setting tool, discloses a liner hanger and a setting tool which have high bearing pressure, realize setting and releasing by one-time operation, do not need to rotate a tubular column, and are suitable for being used in various environments such as shallow wells, deep wells, highly-inclined wells, horizontal wells and the like. However, the invention does not consider the technical problems that the residual exists after the sealing core is repaired for realizing the full-diameter drilling and grinding and the residual processing is difficult and the later operation is influenced, etc. of the traditional tail pipe hanger. Disclosure of Invention The present invention aims to address at least one of the above-mentioned deficiencies of the prior art. For example, one of the purposes of the present invention is to provide a sealed core-supplementing releasing mechanism with a simple structure, which can avoid the occurrence of the "locking" condition. As another example, it is another object of the present invention to provide a liner hanger that reduces the risk of operation. For another example, another object of the present invention is to provide an efficient method of releasing. In order to achieve the above purpose, the invention provides a sealing core supplementing releasing mechanism which comprises a sealing spring claw, a limiting sleeve and a cone body, wherein the cone body is communicated with a hanger body, an insertion pipe is positioned between the cone body and the hanger body, an annular space exists between the insertion pipe and the cone body and between the hanger body, a liquid transmission hole is formed in the insertion pipe, drilling fluid can pass through the liquid transmission hole from the annular space to the insertion pipe, the sealing spring claw is sleeved on the insertion pipe and is of an annular structure and provided with certain elasticity, the inner wall of the cone body is uniformly provided with discontinuous annular grooves in the circumferential direction, the sealing spring claw is positioned in the annular grooves, the limiting sleeve is positioned at the upper end of the sealing spring claw, the limiting sleeve limits the sealing spring claw to be stressed upwards in construction, a reducing section is arranged on the insertion pipe, and when the reducing section reaches the sealing spring claw position, the sealing spring claw is contracted towards the insertion pipe under the self elastic action and is separated from the annular grooves. According to one or more exemplary embodiments of an aspect of the present invention, the annular groove may h