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CN-121993070-A - High-pressure-resistant tail pipe hanger

CN121993070ACN 121993070 ACN121993070 ACN 121993070ACN-121993070-A

Abstract

The invention belongs to the technical field of downhole tools, and particularly relates to a high-pressure-resistant tail pipe hanger. The high-pressure-resistant tail pipe hanger comprises an external device, an internal device, a setting and hanging driving mechanism, an external device and a lower end, wherein the external device comprises a hanging mechanism provided with slips, a backstop barrel capable of pushing the hanging mechanism to prop open the slips, the internal device comprises a setting and hanging driving mechanism, the setting and hanging driving mechanism can be connected with the backstop barrel through a plug cap, the external device is configured to be left in a well after underground construction operation, the internal device is configured to be capable of lifting a wellhead after underground construction operation, the hanging mechanism comprises a hanging mechanism body arranged below the setting and hanging driving mechanism, a taper sleeve, slips and a slip supporting sleeve are sequentially arranged outside the hanging mechanism body, a limiting and fixing barrel is arranged inside the slips and the slip supporting sleeve, the upper end of the limiting and fixing barrel is in butt joint with the taper sleeve, and the lower end of the limiting and slip supporting sleeve is connected with the slip supporting sleeve through a setting and starting pin.

Inventors

  • ZHANG RUI
  • LI FUPING
  • CHEN ZHIFENG
  • GUO CHAOHUI
  • CHEN WUJUN

Assignees

  • 中国石油化工股份有限公司
  • 中石化石油工程技术研究院有限公司

Dates

Publication Date
20260508
Application Date
20241101

Claims (10)

  1. 1. A high pressure resistant liner hanger comprising: An external device comprising a suspension mechanism (8) provided with a taper sleeve (806) and a slip (802), and a tieback cylinder (4) capable of pushing the suspension mechanism (8) to prop open the slip (802); The internal device comprises a seat-hanging driving mechanism (5), wherein the seat-hanging driving mechanism (5) can be connected with the tieback cylinder (4) through a plug cap (3), the plug cap (3) is in a locking state before the seat-hanging driving mechanism (5) is started, the tieback cylinder (4) is fixed, and the seat-hanging driving mechanism (5) is in an unlocking state after being started, and drives the tieback cylinder (4) to move; Wherein the external device is configured to remain in the well after the downhole construction operation and the internal device is configured to be capable of being raised up the well after the downhole construction operation; The hanging mechanism (8) comprises a hanging mechanism body (801) arranged below the sitting and hanging driving mechanism (5), a taper sleeve (806), a slip (802) and a slip supporting sleeve (809) are sequentially arranged on the outer side of the hanging mechanism body (801), a limiting and fixing cylinder (810) is arranged on the inner side of the slip (802) and the inner side of the slip supporting sleeve (809), the upper end of the limiting and fixing cylinder (810) is abutted to the taper sleeve (806), and the lower end of the limiting and fixing cylinder is connected with the slip supporting sleeve (809) through a sitting and sealing starting pin (811).
  2. 2. The high pressure resistant liner hanger of claim 1, wherein the hanging mechanism (8) further comprises a shear pin sleeve (807) disposed outside the hanging mechanism body (801) by unlocking a shear pin (808), an upper end surface of the shear pin sleeve (807) being in contact with a lower end surface of the slip support sleeve (809), an axial gap being present between a lower end portion of the limit fix cylinder (810) and the shear pin sleeve (807).
  3. 3. The high pressure resistant liner hanger according to claim 2, wherein the cone sleeve (806) is connected to the tieback tube (4) through a snap spring sleeve (805) and a hanging mechanism connecting tube (803), and the snap spring sleeve (805) is matched with the hanging mechanism body (801) through an anti-withdrawal snap spring (804).
  4. 4. A high pressure resistant liner hanger according to any of claims 1-3, wherein the seat-hanging driving mechanism (5) comprises a mandrel (501), a hydraulic cylinder (503) is arranged outside the mandrel (501), a piston (502) is arranged in the hydraulic cylinder (503), and the end part of the piston (502) extends into the plug cap (3) and is connected with the plug cap; The piston (502) divides the space inside the hydraulic cylinder (503) into an upper space and a lower space, the mandrel (501) is radially provided with a pressure transmission hole (508), the pressure transmission hole (508) is communicated with the upper space, the outer wall of the lower end of the hydraulic cylinder (503) is provided with a pressure release hole (509), and the pressure release hole (509) is communicated with the lower space; The piston (502) is positioned at a first position at the upstream before sitting and hanging and is connected with the mandrel (501) through a first shear pin (504), the first shear pin (504) is sheared during sitting and hanging, the piston (502) moves downwards and pushes the tieback cylinder (4) to move downwards through the plug cap (3) so as to prop open the slips (802) of the hanging mechanism (8).
  5. 5. The high pressure resistant liner hanger according to claim 4, wherein at least one secondary hydraulic cylinder (511) is further provided outside the mandrel (501), the secondary hydraulic cylinder (511) being located between the hydraulic cylinder (503) and the plug cap (3), a secondary piston (512) being provided inside the secondary hydraulic cylinder (511), the secondary piston (512) being connected to the piston (502); The secondary piston (512) divides the space inside the secondary hydraulic cylinder (511) into an upper space and a lower space, a secondary pressure transmission hole (513) communicated with the upper space is formed in the mandrel (501) in the radial direction, and a pressure release hole (509) communicated with the lower space is formed in the outer wall of the lower end of the secondary hydraulic cylinder (511).
  6. 6. The high pressure resistant liner hanger according to claim 4, wherein an end of the piston (502) is provided with a piston connection cylinder (505) through an extension cylinder (510), and a seat hanging sleeve (506) capable of pushing the plug cap (3) downward is fixed on the piston connection cylinder (505).
  7. 7. The high pressure resistant liner hanger according to any one of claims 1 to 6, wherein the plug cap (3) comprises: A sitting and hanging pushing device (303) connected with the tieback cylinder (4); A support cylinder (333) provided inside the seat-hanging pushing device (303), the support cylinder (333) being configured to be capable of pushing the seat-hanging pushing device (303) axially downward under the action of the seat-hanging driving mechanism (5); A locking block assembly (335) is arranged on the sitting and hanging pushing device (303) in a radial moving way, a tieback cylinder clamping groove (401) is formed in the inner side of the tieback cylinder (4), and the supporting cylinder (333) supports the inner side of the locking block assembly (335) so that the outer end of the locking block assembly (335) is clamped in the tieback cylinder clamping groove (401); After the supporting cylinder (333) moves upwards relative to the sitting and hanging pushing device (303), the supporting of the locking block assembly (355) can be released, so that the locking block assembly (355) is released from clamping the clamping groove (401) of the tieback cylinder.
  8. 8. The high pressure resistant liner hanger as claimed in claim 7, wherein the lock block assembly (355) comprises: a locking block (342) arranged on the sitting and hanging pushing device (303) in a radial moving way; And the locking shear pin (341) is fixedly arranged in the locking block body (342), and the locking shear pin (341) is used for being clamped with the tieback cylinder clamping groove (401).
  9. 9. The high pressure resistant liner hanger according to claim 7, wherein the plug cap (3) further comprises a fixing sleeve (301) connected with a mandrel (501) of the seat hanging driving mechanism (5), the fixing sleeve (301) is connected with the seat hanging pushing device (303) through a connecting body (302), a stop block (312) is axially and movably arranged in the outer wall of the fixing sleeve (301), a clamping groove (322) is arranged in the inner wall of the connecting body (302), and a piston connecting cylinder (505) of the seat hanging driving mechanism (5) stretches into the fixing sleeve (301) and supports the stop block (312) so that the outer end of the stop block (312) is clamped in the clamping groove (322).
  10. 10. The high pressure resistant liner hanger according to any of claims 1-9, wherein a central tube (9) is connected below the seat-hanging driving mechanism (5) through a releasing mechanism (6), and a sealing core (7) is arranged between the central tube (9) and the hanging mechanism (8).

Description

High-pressure-resistant tail pipe hanger Technical Field The invention belongs to the technical field of downhole tools, and particularly relates to a high-pressure-resistant tail pipe hanger. Background The liner hanger is a downhole tool commonly used in petroleum exploration and development at present, and can be divided into three types of mechanical type, hydraulic type and hydraulic mechanical double-acting type according to different sitting and hanging modes, and the hydraulic type liner hanger is most widely applied. The hydraulic liner hanger is started by holding pressure in the pipe. At present, in order to solve the difficult problems of liner cementing under complex well conditions such as deep wells, small-clearance wells, large-displacement wells and the like, a plurality of different types of hydraulic liner hangers are developed in China successively, and the hydraulic liner hangers have the characteristics of high bearing capacity, high running reliability and the like. However, the sitting and hanging driving mechanism of the traditional hydraulic tail pipe hanger is designed outside the hanger body, and is remained in the well for a long time after the well cementation construction is finished, and the sitting and hanging driving mechanism inevitably needs to use a rubber sealing piece which is easy to age in a high-temperature and high-pressure environment in the well for a long time, so that the sealing failure of the sitting and hanging driving mechanism is caused, and the sealing durability of the whole shaft is affected. Chinese patent document CN112227993a discloses a liner hanger with a recoverable driving mechanism, which transfers a seat-hanging driving mechanism to a running tool and recovers with the running tool after cementing, thereby effectively eliminating potential leakage risk points of the liner hanger and improving pressure resistance and sealing durability of the tool. The liner hanger still has the following problems. The suspension mechanism is not highly reliable. The existing liner hanger sitting and hanging slips are fixed with the body through the slip supporting sleeve, so that the liner hanger is ensured to shrink in an initial state and the inside of the taper sleeve, and the liner hanger is prevented from expanding in advance. After the ball is thrown and pressed, the taper sleeve descends relative to the body and the slips, so that the slips are unfolded to form an initial sitting and hanging. To achieve full reliability of the setting, relative movement between the slip and the cone sleeve is required when the body (tail pipe weight) is lowered, however, the slip and the slip support sleeve are fixed to the body, and the cone sleeve is also fixed to the body in one direction through the snap spring, which results in direct and unable free relative movement of the slip and the cone sleeve after the initial setting is formed, i.e. when the body is lowered, the body may drive the slip to move down together, thereby possibly causing failure of setting of the tail pipe hanger. That is, the manner of directly securing the slips and slip cone sleeve to the body, while effective to prevent the slips from setting in advance, may result in failure of the liner hanger to set. The construction safety is not enough, and the emergency releasing function is lacking. This tail pipe hanger is through preventing to sit in advance to hang cock cap mechanism, locks tieback section of thick bamboo and running tool to can prevent that the tail pipe from going into in-process tieback section of thick bamboo receives external force effect and lead to the possibility that the tail pipe hanger sits in advance to hang, only pitch the ball to hold down after pressing, actuating mechanism action just can realize tieback section of thick bamboo and running tool's locking, thereby continue to sit and hang the tail pipe hanger. However, in the actual construction process, the holding pressure cannot be realized after the ball is thrown due to some reasons, namely, the sitting and hanging driving mechanism cannot act, so that the tail pipe hanger and the lower pipe string cannot be released, and more serious construction accidents are caused. Thus, a new liner hanger is needed. Disclosure of Invention The present invention aims to solve at least one of the above problems by providing a high pressure resistant liner hanger. According to the present invention there is provided a high pressure resistant liner hanger comprising: The external device comprises a hanging mechanism provided with a taper sleeve and a slip, and a tieback cylinder capable of pushing the hanging mechanism to prop the slip open; The internal device comprises a sitting and hanging driving mechanism, the sitting and hanging driving mechanism can be connected with the tieback cylinder through a plug cap, the plug cap is in a locking state before the sitting and hanging driving mechanism is started and fixes the tieback