Torsion mechanism of hydraulic back-off device

Abstract

The utility model discloses a hydraulic back-off device torsion mechanism which comprises a ball outer barrel, a piston barrel is arranged in the ball outer barrel, a ball torque shaft is arranged in the piston barrel, the lower end of the ball torque shaft is exposed out of the lower end of the ball outer barrel, and a plurality of ball outer barrel spiral guide grooves are formed in the inner wall face of the lower portion of the ball outer barrel. A plurality of piston barrel spiral guide grooves are formed in the outer wall face of the lower portion of the piston barrel, a plurality of piston barrel ball grooves are formed in the inner wall face of the lower portion of the piston barrel, through holes penetrating through the wall face of the piston barrel are formed in the two ends of each piston barrel spiral guide groove, and the piston barrel spiral guide grooves and the piston barrel ball grooves in the corresponding positions are communicated through the through holes. A plurality of torque shaft ball grooves are formed in the outer wall face of the upper portion of the ball torque shaft, a plurality of steel balls are arranged in the piston barrel spiral guide groove and the piston barrel ball grooves, a plurality of limiting bolts are arranged in a cavity between the outer wall face of the ball torque shaft and the inner wall face of the ball outer barrel, and the steel balls are sealed in the piston barrel ball grooves through the limiting bolts.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas well drilling and workover, and in particular to a hydraulic reverser torsion mechanism. Background Technology

[0002] During the later stages of oil and gas well development, production enhancement measures need to be implemented. During drilling and repair operations / production enhancement measures, pipe string jamming accidents frequently occur. Once a jamming accident occurs, it will increase the operation cycle and cost, and in severe cases, it will cause the well to be scrapped.

[0003] Currently, common handling measures for stuck drill pipe include: (1) reverse-threading the stuck point by reverse-threading the drill pipe; (2) cutting the stuck point by cutting; (3) explosive loosening technique; (4) planetary gear mechanical reverse-threading tool; and (5) hydraulic reverse-threading tool specifically designed for highly deviated and horizontal wells. However, in actual operation, these techniques have significant limitations. For example, reverse-threaded drill pipe is not stocked at the well site and needs to be prepared separately, resulting in high production and transportation costs and requiring a large construction site. Torque is transmitted from the wellhead to the bottom of the well, resulting in significant energy loss and reduced drill pipe life. Cutting methods damage the tubing string and are cumbersome due to space constraints. Explosive loosening tools address some on-site issues to a certain extent, performing loosening operations well in a single back-locking operation, but are unsuitable for subsequent back-locking operations. Planetary gear back-locking tools, due to tool size limitations, have small planetary gears with low strength, resulting in low overall tool output torque, which cannot meet the requirements for high-torque back-locking operations.

[0004] Therefore, a hydraulic reverse-coupling tool has been developed for reverse-coupling operations in highly deviated and horizontal wells, consisting of a hydraulic anchor and a reverse-coupling device. The upper hydraulic anchor is pressurized and anchored to the casing, providing the reverse-coupling reaction force for the lower reverse-coupling device, while also avoiding the risk of rotational uncoupling of the upper tubing string. The lower hydraulic reverse-coupling device mainly consists of three parts: a pressure boosting mechanism, a torsion mechanism, and a power output mechanism. The pressure boosting mechanism provides axial driving force through a two-stage piston system. The existing torsion mechanism uses the relative motion of a left-hand helical mandrel and a left-hand helical spline sleeve to convert axial force into left-hand torque. The power output mechanism adopts an inner and outer double ratchet design, with the inner and outer ratchets independent of each other. The inner ratchet is not affected by the lower rotational torque, while the outer ratchet ensures that the reverse-coupling torque already applied will not rotate.

[0005] This tool is safe and reliable in operation, with a large output torque. However, in actual operation, these processing methods have significant limitations. Feedback from field use indicates that under the action of large axial torque, the contact area between the spiral mandrel and the sawtooth thread of the spiral spline sleeve is too large, resulting in excessive contact stress during movement. This poses a risk of the spiral mandrel thread sticking together and becoming unable to return to its original position during repeated reversing operations. Utility Model Content

[0006] To address the risk of existing hydraulic rewinding tools experiencing thread sticking and inability to reset during repeated rewinding operations, this invention provides a hydraulic rewinder torsion mechanism that converts axial driving force into rotational torque. This mechanism reduces contact stress while meeting the requirements for high torque output, making the operation safer and more reliable.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0008] A hydraulic reverser torsion mechanism includes a ball bearing outer cylinder, a piston cylinder inside the outer cylinder, a ball bearing torque shaft inside the piston cylinder, and the lower end of the ball bearing torque shaft protruding from the lower end of the outer cylinder. Multiple spiral guide grooves are formed on the lower inner wall of the outer cylinder, multiple spiral guide grooves are formed on the lower outer wall of the piston cylinder, and multiple ball bearing grooves are formed on the lower inner wall of the piston cylinder. Through holes are formed at both ends of the spiral guide grooves, connecting the spiral guide grooves and corresponding ball bearing grooves. Multiple ball bearing grooves are formed on the upper outer wall of the ball bearing torque shaft. Several steel balls are contained within the spiral guide grooves and ball bearing grooves. Multiple limiting pins are installed in the cavity between the outer wall of the ball bearing torque shaft and the inner wall of the outer cylinder, sealing the steel balls within the ball bearing grooves.

[0009] Furthermore, the number of the outer ball cylinder spiral guide groove, the piston cylinder spiral guide groove, the piston cylinder ball groove, the limiting pin, and the torque shaft ball groove are the same.

[0010] Furthermore, the outer cylinder of the ball bearing has five spiral guide grooves, which extend in a spiral shape along the inner wall of the outer cylinder of the ball bearing.

[0011] Furthermore, the piston cylinder has five spiral guide grooves and five ball grooves.

[0012] Furthermore, the piston cylinder ball groove extends axially, with its lower end extending to the lower end face of the piston cylinder, and two through holes on each piston cylinder ball groove are respectively opened at the upper end and the lower part of the piston cylinder ball groove.

[0013] Furthermore, the number of limiting pins is 5, the limiting pins are fan-shaped in general, and their cross-section along the axial direction is L-shaped. The lower rear end of the limiting pin is provided with a protrusion that matches the ball groove of the torque shaft, and the front end of the limiting pin is provided with an arc groove that matches the shape of the steel ball.

[0014] Furthermore, the torque shaft has five ball grooves, the upper end of which extends axially to the upper end face of the ball torque shaft.

[0015] Furthermore, the upper end of the ball bearing outer cylinder is connected to the upper tubular column.

[0016] Compared with the prior art, the outstanding effect of the hydraulic reverser torsion mechanism of this utility model is as follows:

[0017] (1) The hydraulic reverser torsion mechanism of this utility model adopts an innovative ball torsion structure. Five complete ball guide grooves are evenly distributed around the lower end of the piston to form an independent closed ball circuit. Compared with the left-hand torque transmitted by the thread, the steel ball has the advantage of smaller contact stress. The ball structure is flexible and there is no risk of jamming or obstruction. It completely solves the risk of jamming or obstruction that may be caused by the original thread mechanism.

[0018] (2) The hydraulic reverser torsion mechanism of this utility model adopts a separate steel ball closed circuit, which satisfies the transmission of large torque while ensuring flexible movement.

[0019] (3) The hydraulic reverser torsion mechanism of this utility model has a large transmission torque, simple and reliable structure and operation, and is convenient for later maintenance.

[0020] The hydraulic reverser torsion mechanism of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0021] Figure 1 This is a half-sectional schematic diagram of the torsion mechanism of the hydraulic reverser.

[0022] Figure 2 This is a schematic diagram of the motion of the hydraulic reverser's torsion mechanism.

[0023] Figure 3 This is a half-sectional schematic diagram of the outer cylinder of the ball bearing.

[0024] Figure 4 This is a half-section diagram of the piston.

[0025] Figure 5 This is a half-section diagram of the ball torque shaft.

[0026] Figure 6 This is a cross-sectional view of the limiting pin along the axial direction.

[0027] Figure 7The right view shows the assembly relationship between the limit pin and the ball torque shaft.

[0028] Among them, 1-ball bearing outer cylinder, 2-piston cylinder, 3-steel ball, 4-limiting pin, 5-ball bearing torque shaft; 11-ball bearing outer cylinder spiral guide groove, 21-piston cylinder spiral guide groove, 22-piston cylinder ball groove, 23-through hole, 41-protrusion, 42-arc surface groove, 51-torque shaft ball groove. Detailed Implementation

[0029] Unless otherwise specified, "above," "upper end," "front end," and "upper part" in this article refer to... Figure 1-6 The left side, bottom, lower end, rear end, and rear part represent the middle left, lower right, lower left, and rear right. Figure 1-6 Right side of the middle.

[0030] like Figure 1-7 As shown, a hydraulic reverser torsion mechanism includes a ball bearing outer cylinder 1, a piston cylinder 2 inside the ball bearing outer cylinder 1, a ball bearing torque shaft 5 inside the piston cylinder 2, and the lower end of the ball bearing torque shaft 5 protruding from the lower end of the ball bearing outer cylinder 1. Multiple ball bearing outer cylinder spiral guide grooves 11 are formed on the lower inner wall of the ball bearing outer cylinder 1. Multiple piston cylinder spiral guide grooves 21 are formed on the lower outer wall of the piston cylinder 2. Multiple piston cylinder ball grooves 22 are formed on the lower inner wall of the piston cylinder 2. The two sides of the piston cylinder spiral guide grooves 21... Each end is provided with a through hole 23 that penetrates the wall of the piston cylinder 2. The through hole 23 connects the piston cylinder spiral guide groove 21 and the corresponding piston cylinder ball groove 22. Multiple torque shaft ball grooves 51 are provided on the upper outer wall of the ball torque shaft 5. Several steel balls 3 are installed in the piston cylinder spiral guide groove 21 and the piston cylinder ball groove 22. Multiple limiting pins 4 are installed in the cavity between the outer wall of the ball torque shaft 5 and the inner wall of the ball outer cylinder 1. The limiting pins 4 enclose the steel balls 3 in the piston cylinder ball groove 22.

[0031] The outer cylinder of the ball bearing has five spiral guide grooves 11, which extend in a spiral shape along the inner wall of the outer cylinder of the ball bearing.

[0032] The piston cylinder has five spiral guide grooves 21 and five ball grooves 22. The ball grooves 22 extend axially, with their lower ends extending to the lower end face of the piston cylinder 2. Two through holes 23 are respectively opened at the upper and lower ends of each ball groove 22.

[0033] There are five limiting pins 4. The limiting pins 4 are fan-shaped in general, and their cross-section along the axial direction is L-shaped. The lower rear end of the limiting pin 4 is provided with a protrusion 41 that matches the ball groove 51 of the torque shaft. The front end of the limiting pin 4 is provided with an arc groove 42 that matches the shape of the steel ball 3. The outer rear part of the limiting pin 4 abuts against the inner wall of the outer ball cylinder 1.

[0034] There are five torque shaft ball grooves 51, the upper ends of which extend axially to the upper end face of the ball torque shaft 5. The positions of the five torque shaft ball grooves 51 are aligned with the positions of the five piston cylinder ball grooves 22.

[0035] Each ball outer cylinder spiral guide groove 11 is connected to the corresponding piston cylinder spiral guide groove 21, and the steel ball 3 can move within the space enclosed by the two.

[0036] When the piston cylinder 2 moves downward under axial pressure, the steel ball 3 in the piston cylinder spiral guide groove 21 can only rotate downward along the outer spiral guide groove 11 of the ball bearing cylinder due to space constraints, thereby driving the piston cylinder 2 to rotate. The steel ball 3 in the space enclosed by the piston cylinder ball bearing groove 22 and the torque shaft ball bearing groove 51 then drive the ball torque shaft 5 to rotate.

[0037] The upper end of the ball bearing outer cylinder 1 is connected to the upper tubular column.

[0038] like Figure 1 As shown, the assembly sequence of the hydraulic buckle twisting mechanism from left to right is as follows:

[0039] (1) The piston cylinder 2 is inserted into the 45° shoulder from the left end of the ball outer cylinder 1;

[0040] (2) The upper end of the ball torque shaft 5 is inserted from the lower end of the piston cylinder 2;

[0041] (3) Insert a sufficient number of steel balls 3 into the torque shaft ball groove 51 on the ball torque shaft 4 in sequence, and fill all 5 piston cylinder ball grooves 22 and their connected piston cylinder spiral guide grooves 21.

[0042] (4) Insert the limit pins 4 into the ball grooves 51 of the 5 torque shafts in sequence.

[0043] The working principle of the hydraulic reverser's torsion mechanism is as follows: When the inside of the tubing is pressurized, the ball bearing outer cylinder 1 is fixed relative to the upper end of the tubing, and the pressure inside the pipe is converted into axial thrust, pushing the piston cylinder 2 downward. The steel ball 3 in the piston cylinder spiral guide groove 21 at the lower end of the piston cylinder 2 is subjected to force and rotates along the ball bearing outer cylinder spiral guide groove 11 of the ball bearing outer cylinder 1. After completing one spiral motion along the spiral guide groove, the steel ball 3 enters the piston cylinder ball groove 22 and the torque shaft ball groove 51 through the lower through hole 23. The steel ball in the piston cylinder ball groove 22 enters the piston cylinder spiral guide groove 21 through the upper through hole 23. Driven by the steel ball 3, the ball bearing torque shaft 5 rotates together with the piston cylinder 2, thereby transmitting torque to the retrieval tool below for reverser operation.

[0044] In use, the working process of the hydraulic reversing device's torsion mechanism is as follows:

[0045] (1) When the tubing is pressurized, the upper anchor is set inside the casing;

[0046] (2) As the tubing continues to be pressurized, the pressure inside the tubing is converted into axial thrust, which pushes the piston cylinder downward;

[0047] (3) The steel ball at the lower end of the piston cylinder rotates along the multi-threaded spiral guide groove inside the ball outer cylinder;

[0048] (4) In the closed track groove, the steel ball enters the piston cylinder ball groove and the torque shaft ball groove of the ball torque shaft along the spiral guide groove of the outer ball cylinder.

[0049] (5) Under the action of the steel ball, the piston drives the ball torque shaft to generate left-hand torsional motion, generating left-hand torque.

[0050] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. They should not be construed as limitations on the present utility model. Any modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A hydraulic reversing device torsion mechanism, characterized in that: The device includes a ball bearing outer cylinder (1), a piston cylinder (2) inside the ball bearing outer cylinder (1), a ball bearing torque shaft (5) inside the piston cylinder (2), the lower end of the ball bearing torque shaft (5) protruding from the lower end of the ball bearing outer cylinder (1), multiple ball bearing outer cylinder spiral guide grooves (11) formed on the lower inner wall surface of the ball bearing outer cylinder (1), multiple piston cylinder spiral guide grooves (21) formed on the lower outer wall surface of the piston cylinder (2), multiple piston cylinder ball grooves (22) formed on the lower inner wall surface of the piston cylinder (2), and through pistons formed at both ends of the piston cylinder spiral guide grooves (21). The through hole (23) on the wall of the cylinder (2) connects the piston cylinder spiral guide groove (21) and the piston cylinder ball groove (22) at the corresponding position. Multiple torque shaft ball grooves (51) are opened on the upper outer wall of the ball torque shaft (5). Several steel balls (3) are installed in the piston cylinder spiral guide groove (21) and the piston cylinder ball groove (22). Multiple limiting pins (4) are installed in the cavity between the outer wall of the ball torque shaft (5) and the inner wall of the ball outer cylinder (1). The limiting pins (4) enclose the steel balls (3) in the piston cylinder ball groove (22).

2. The hydraulic reverser torsion mechanism according to claim 1, characterized in that: The number of the outer ball cylinder spiral guide groove (11), piston cylinder spiral guide groove (21), piston cylinder ball groove (22), limit pin (4) and torque shaft ball groove (51) are the same.

3. The hydraulic reverser torsion mechanism according to claim 2, characterized in that: The number of spiral guide grooves (11) on the outer cylinder of the ball bearing is 5, which extend in a spiral shape along the inner wall surface of the outer cylinder of the ball bearing (1).

4. The hydraulic reverser torsion mechanism according to claim 3, characterized in that: The number of piston cylinder spiral guide grooves (21) and piston cylinder ball grooves (22) are both 5.

5. The hydraulic reverser torsion mechanism according to claim 4, characterized in that: The piston cylinder ball groove (22) extends along the axial direction, and its lower end extends to the lower end face of the piston cylinder (2). Two through holes (23) on each piston cylinder ball groove (22) are respectively opened at the upper end and the lower part of the piston cylinder ball groove (22).

6. The hydraulic reverser torsion mechanism according to claim 5, characterized in that: The number of the limiting pins (4) is 5. The limiting pins (4) are fan-shaped in general and have an L-shaped cross section along the axial direction. The lower rear end of the limiting pins (4) is provided with a protrusion (41) that matches the ball groove (51) of the torque shaft. The front end of the limiting pins (4) is provided with an arc groove (42) that matches the shape of the steel ball (3).

7. The hydraulic reverser torsion mechanism according to claim 6, characterized in that: The torque shaft ball groove (51) has five grooves, the upper end of which extends axially to the upper end face of the ball torque shaft (5).

8. The hydraulic reverser torsion mechanism according to claim 7, characterized in that: The upper end of the ball bearing outer cylinder (1) is connected to the upper tubular column.

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