CN107859495B

CN107859495B - Telescopic underground tractor

Info

Publication number: CN107859495B
Application number: CN201711406526.XA
Authority: CN
Inventors: 夏成宇; 黄剑; 钱利勤; 李旭; 刘先明; 柴泽宇
Original assignee: Yangtze University
Current assignee: Hainan Jia'en Yuandong Intellectual Property Services Co ltd
Priority date: 2017-12-22
Filing date: 2017-12-22
Publication date: 2023-06-30
Anticipated expiration: 2037-12-22
Also published as: CN107859495A

Abstract

The invention relates to a telescopic underground tractor, and belongs to the technical field of underground traction tools for petroleum and natural gas. The device consists of an upper joint, a shell, a turbine shaft, a swash plate hydraulic pump, a flow distributor, a telescopic oil cylinder and a telescopic head, wherein the turbine shaft is arranged in the shell through symmetrically arranged turbine bearings; a swash plate hydraulic pump is arranged in the shell below the turbine shaft through a hydraulic pump bearing, a flow distributor is arranged in the shell below the swash plate hydraulic pump, and the flow distributor is communicated with the swash plate hydraulic pump; a rear claw cylinder and a telescopic cylinder are sequentially arranged in the shell below the flow distributor, and the rear claw cylinder and the telescopic cylinder are respectively communicated with the flow distributor. The tractor controls the telescopic movement of the front claw cylinder, the rear claw cylinder and the telescopic cylinder through the flow distributor. Thereby effecting forward movement of the retractor. The problems that the existing tractor is large in underground friction resistance, difficult to put in and take out and difficult to apply drilling pressure are effectively solved; the method is particularly suitable for pulling the coiled tubing in well workover, well completion and other operations.

Description

Telescopic underground tractor

Technical Field

The invention relates to a telescopic underground tractor, and belongs to the technical field of underground traction tools for petroleum and natural gas.

Background

The downhole tractor, i.e. the downhole crawler, is also called a downhole crawling mechanism, a downhole tractor, a downhole towing robot, a downhole hydraulic pressurizer, a downhole drill bit propeller, etc., and is a downhole tool capable of providing traction at the bottom of the well. The underground tractor can be divided into 3 types of roller crawling type, crawler crawling type (caterpillar track type) and telescopic sliding type (stepping type) of a grabbing arm according to the movement principle, wherein the wheels are earliest in appearance, the telescopic type is inferior, and the crawler type is latest. Traction crawlers can be classified into 3 types of CT type, cable type and hybrid type according to energy sources thereof. For domestic, strict technical security measures are adopted abroad, so that domestic research on the underground tractor is still in the stage of just starting. At present, most of domestic existing tractors have the defects of poor structural reliability, large underground friction resistance, difficult loading and unloading, difficult application of drilling pressure and the like due to design reasons, so that a pure hydraulic underground tool tractor which has a simple structure and can effectively solve the technical problems of large underground friction resistance, difficult loading and unloading, difficult application of drilling pressure and the like is necessary to be developed.

Disclosure of Invention

The invention aims at: the coiled tubing tractor has a simple structure, and can effectively solve the problems that the conventional tractor is large in downhole friction, difficult to take in and out and difficult to apply the weight on bit.

The technical scheme of the invention is as follows:

the utility model provides a telescopic tractor in pit, it comprises top connection, shell, turbine shaft, sloping cam plate hydraulic pump, current distributor, telescopic cylinder and flexible head, its characterized in that: an upper joint is arranged on the top of the shell in a threaded manner, and a turbine shaft is arranged in the shell below the upper joint through symmetrically arranged turbine bearings; a turbine assembly is arranged on the turbine shaft between the turbine bearings, a swash plate hydraulic pump is arranged in the shell below the turbine shaft through a hydraulic pump bearing, a flow distributor is arranged in the shell below the swash plate hydraulic pump, and the flow distributor is communicated with the swash plate hydraulic pump; the swash plate hydraulic pump is connected with the turbine shaft; a rear claw oil cylinder and a telescopic oil cylinder are sequentially arranged in the shell below the flow distributor, and the rear claw oil cylinder and the telescopic oil cylinder are respectively communicated with the flow distributor; a rear claw is arranged on the shell corresponding to the rear claw oil cylinder, one end of the rear claw extends to the outer end of the shell, and the other end of the rear claw is in sliding connection with the rear claw oil cylinder; a telescopic head is arranged below the shell and is connected with a piston rod of the telescopic oil cylinder.

The swash plate hydraulic pump consists of a main shaft, a hydraulic pump swash plate, a hydraulic pump valve plate, a hydraulic pump cylinder body, a hydraulic pump plunger, a plunger spring, a hydraulic pump oil tank, an oil outlet pipe, an oil return pipe, an oil tank piston and an oil tank spring, wherein the hydraulic pump oil tank is arranged below the hydraulic pump cylinder body through the hydraulic pump valve plate, the hydraulic pump plunger is symmetrically and movably arranged on the hydraulic pump cylinder body through the plunger spring, and the hydraulic pump plunger is communicated with the hydraulic pump oil tank through the hydraulic pump valve plate; a hydraulic pump swash plate is arranged above the hydraulic pump plunger through a main shaft, the hydraulic pump swash plate is connected with the hydraulic pump plunger in a sliding contact manner, and the main shaft is fixedly connected with a turbine shaft; the hydraulic pump oil tank is internally provided with an oil tank piston through an oil tank spring, the central part of the oil tank piston is provided with an oil outlet pipe, one end of the oil outlet pipe is communicated with a hydraulic pump valve plate, the other end of the oil outlet pipe is communicated with a flow distributor, and the flow distributor is communicated with the hydraulic pump oil tank through an oil return pipe.

The rear conical push block is arranged at the end of a piston rod of the rear claw cylinder, a clamping groove is formed in the rear conical push block, a clamping head is arranged at the end of the rear claw corresponding to the rear conical push block, the rear conical push block and the rear claw are in matched sliding connection with the clamping head through the clamping groove, and the rear claw cylinder is communicated with the flow distributor through a rod cavity oil pipe of the rear claw cylinder and a rodless cavity oil pipe of the rear claw cylinder.

The telescopic oil cylinder is communicated with the flow distributor through a telescopic cylinder rod cavity oil pipe and a telescopic cylinder rod-free cavity oil pipe.

The telescopic head consists of a shell, a front claw cylinder, a front conical push block and a front claw, wherein the front claw cylinder is fixedly arranged in the shell, the front conical push block is arranged at the end head of a piston rod of the front claw cylinder, a clamping groove is formed in the front conical push block, a front claw is arranged on the shell corresponding to the front conical push block, one end of the front claw extends to the outer end of the shell, a clamping head corresponding to the clamping groove is arranged at the end head of the other end of the front claw, and the front conical push block and the front claw are in matched sliding connection through the clamping groove and the clamping head.

The telescopic oil cylinder is characterized in that a telescopic oil pipe A and a telescopic oil pipe B are installed in a telescopic cylinder piston rod of the telescopic oil cylinder, one end of the telescopic oil pipe A is communicated with the flow distributor through a front claw rod cavity oil pipe, the other end of the telescopic oil pipe A is communicated with an upper cavity of the front claw oil cylinder, one end of the telescopic oil pipe B is communicated with the flow distributor through a front claw rod-free cavity oil pipe, and the other end of the telescopic oil pipe B is communicated with a lower cavity of the front claw oil cylinder.

The invention has the beneficial effects that:

in the working process of the telescopic underground tractor, the energy of drilling fluid is converted into the energy of a hydraulic system in equipment through the combination of rotation of a turbine state and a swash plate hydraulic pump, and the telescopic movement of a front claw oil cylinder, a rear claw oil cylinder and a telescopic oil cylinder is controlled through a flow distributor. Thereby effecting forward movement of the retractor. The downhole friction-resistant tractor has the characteristics of high power, high traction force and good stability, and effectively solves the problems that the existing tractor is large in downhole friction resistance, difficult to put in and take out and difficult to apply drilling pressure; the method is particularly suitable for pulling the coiled tubing in well workover, well completion and other operations.

Drawings

FIG. 1 is a schematic diagram of the structure of the present invention;

FIG. 2 is an enlarged schematic view of the structure of FIG. 1 at A;

fig. 3 is an enlarged schematic view of the structure at B in fig. 1.

In the figure: 1. the hydraulic pump comprises an upper joint, 2, a shell, 3, a turbine shaft, 4, a distributor, 5, a turbine bearing, 6, a turbine assembly, 7, a hydraulic pump bearing, 8, a main shaft, 9, a hydraulic pump swash plate, 10, a hydraulic pump distributing plate, 11, a hydraulic pump cylinder body, 12, a hydraulic pump plunger, 13, a plunger spring, 14, a hydraulic pump oil tank, 15, an oil outlet pipe, 16, an oil return pipe, 17, an oil tank piston, 18, an oil tank spring, 19, a rear claw cylinder, 20, a telescopic cylinder, 21, a rear conical push block, 22, a rear claw, 23, a rear claw cylinder with a rod cavity oil pipe, 24, a rear claw cylinder without a rod cavity oil pipe, 25, a telescopic cylinder with a rod cavity oil pipe, 26, a telescopic cylinder without a rod cavity oil pipe, 27, a shell, 28, a front claw cylinder, 29, a front conical push block, 30, front claw, 31, telescopic oil pipes A,32, telescopic oil pipes B,33, a front claw with a rod cavity oil pipe, 34, a front claw without a rod cavity oil pipe, 35 and a water outlet hole.

Detailed Description

The telescopic underground tractor consists of an upper joint 1, a shell 2, a turbine shaft 3, a swash plate hydraulic pump, a flow distributor 4, a telescopic oil cylinder 20 and a telescopic head, wherein the upper joint 1 is arranged on the top of the shell 2 in a threaded manner, and the turbine shaft 3 is arranged in the shell 2 below the upper joint 1 through symmetrically arranged turbine bearings 5; a turbine assembly 6 (comprising a rotor and a stator) is arranged on the turbine shaft 3 between the turbine bearings 5, and a swash plate hydraulic pump is arranged in the housing 2 below the turbine shaft 3 through a hydraulic pump bearing 7. The swash plate hydraulic pump comprises a main shaft 8, a hydraulic pump swash plate 9, a hydraulic pump valve plate 10, a hydraulic pump cylinder body 11, a hydraulic pump plunger 12, a plunger spring 13, a hydraulic pump oil tank 14, an oil outlet pipe 15, an oil return pipe 16, an oil tank piston 17 and an oil tank spring 18, wherein the hydraulic pump oil tank 14 is arranged below the hydraulic pump cylinder body 11 through the hydraulic pump valve plate 10, the hydraulic pump plunger 12 is symmetrically and movably arranged on the hydraulic pump cylinder body 11 through the plunger spring 13, and the hydraulic pump plunger 12 is communicated with the hydraulic pump oil tank 14 through the hydraulic pump valve plate 10.

A hydraulic pump swash plate 9 is arranged above the hydraulic pump plunger 12 through a main shaft 8, the hydraulic pump swash plate 9 is connected with the hydraulic pump plunger 12 in a sliding contact manner, and the main shaft 8 is fixedly connected with the turbine shaft 3; the hydraulic pump oil tank 14 is internally provided with an oil tank piston 17 through an oil tank spring 18, the central part of the oil tank piston 17 is provided with an oil outlet pipe 15, and one end of the oil outlet pipe 15 is communicated with the hydraulic pump valve plate 10.

A distributor 4 (commercially available) is arranged in the shell 2 below the swash plate hydraulic pump, the other end of the oil outlet pipe 15 is communicated with the distributor 4, and the distributor 4 is communicated with the hydraulic pump oil tank 14 through an oil return pipe 16. A rear claw cylinder 19 and a telescopic cylinder 20 are sequentially arranged in the shell 2 below the distributor 4. The piston rod end of the rear claw cylinder 19 is provided with a rear conical push block 21, the rear conical push block 21 is provided with a clamping groove, the shell 2 corresponding to the rear claw cylinder 19 is provided with a rear claw 22, one end of the rear claw 22 extends to the outer end of the shell 2, the end of the rear claw 22, corresponding to the rear conical push block 21, of the other end of the rear claw 22 is provided with a clamping head, the rear conical push block 21 and the rear claw 22 are in sliding connection with the clamping head in a matched manner, and the rear claw cylinder 19 is communicated with the current distributor 4 through a rear claw cylinder rod cavity oil pipe 23 and a rear claw cylinder rod cavity oil pipe 24.

The telescopic cylinder 20 is communicated with the flow distributor 4 through a telescopic cylinder rod cavity oil pipe 25 and a telescopic cylinder rod cavity-free oil pipe 26.

The shell 2 below is provided with the telescopic head, the telescopic head comprises casing 27, preceding jack catch hydro-cylinder 28, preceding toper ejector pad 29 and preceding jack catch 30, preceding jack catch hydro-cylinder 28 is equipped with to the fixed in casing 27, preceding toper ejector pad 29 is installed to the piston rod end of preceding jack catch hydro-cylinder 28, be provided with the draw-in groove on the preceding toper ejector pad 29, be provided with preceding jack catch 30 on the casing 27 that corresponds with preceding toper ejector pad 29, the one end of preceding jack catch 30 extends to casing 27 outer end, the other end of preceding jack catch 30 is provided with the dop that corresponds with the draw-in groove, cooperation sliding connection through draw-in groove and dop between preceding toper ejector pad 29 and the preceding jack catch 30. The telescopic head is connected with a telescopic cylinder piston rod of the telescopic cylinder 20 through a shell 27.

A telescopic oil pipe A31 and a telescopic oil pipe B32 are installed in a piston rod of a telescopic oil cylinder 20 of the telescopic underground tractor, one end of the telescopic oil pipe A31 is communicated with a flow distributor 4 through a front claw rod cavity oil pipe 33, the other end of the telescopic oil pipe A31 is communicated with an upper cavity of a front claw oil cylinder 28, one end of the telescopic oil pipe B32 is communicated with the flow distributor 4 through a front claw rod-free cavity oil pipe 34, and the other end of the telescopic oil pipe B32 is communicated with a lower cavity of the front claw oil cylinder 28. The telescopic head is fixedly connected with a piston rod of the telescopic cylinder 20 through a shell 27. The purpose of installing flexible oil pipe A31 and flexible oil pipe B32 in the piston rod of flexible hydro-cylinder 20 is to guarantee that flexible hydro-cylinder 20 drives the flexible in-process of stretching head through the piston rod, preceding jack catch hydro-cylinder 28 can remain all the time with the oil circuit intercommunication of joining in marriage the flow ware 4, and then guarantees the normal work of preceding jack catch hydro-cylinder 28.

When the telescopic downhole tractor works, drilling fluid enters from the upper joint 1, and flows out from the water outlet hole 35 after the turbine assembly 6 drives the turbine shaft 3 to rotate. The turbine shaft 3 drives the hydraulic pump swash plate 9 to rotate, and the hydraulic pump plunger 12 is extruded when the hydraulic pump swash plate 9 rotates, so that high-pressure hydraulic oil is provided for the whole system. In the process, the oil tank piston 17 in the hydraulic pump oil tank 14 is lifted upwards under the pushing action of the oil tank spring 1, so that a cavity caused by the volume change of hydraulic oil in the hydraulic oil tank can be compensated, and the oil absorption of the hydraulic pump plunger 12 is facilitated. The pumped hydraulic oil enters the flow distributor 4, and the flow distributor 4 automatically opens corresponding valves according to the pressure of each oil cylinder, so as to control the action of each oil cylinder. The method comprises the following steps:

the distributor 4 presses the upper oil cavity of the front claw oil cylinder 28 through the front claw rod cavity oil pipe 33 and the telescopic oil pipe A31, and the piston rod of the front claw oil cylinder 28 drives the front conical push block 29 to move downwards, so that the front claw 30 is extruded out and clamps the well wall; at this time, the flow distributor 4 presses the lower oil cavity of the telescopic oil cylinder 20 through the oil pipe 25 with the rod cavity of the telescopic oil cylinder to push the piston rod of the telescopic oil cylinder 20 to retract, in the process, the front claw 30 of the front claw oil cylinder 28 is clamped on the well wall, the piston rod of the telescopic oil cylinder 20 drives the shell 2 to integrally move forward in the retracting process, and the piston rod of the telescopic oil cylinder 20 is retracted in place; the distributor 4 presses the oil pipe 23 with a rod cavity of the rear claw cylinder to the upper oil cavity of the rear claw cylinder 19, so that the piston rod of the rear claw cylinder 19 is forced to drive the rear conical push block 21 to move downwards, and the rear claw 22 is extruded out and clamps the well wall.

After the above actions are completed, the distributor 4 presses the lower oil cavity of the front claw cylinder 28 through the front claw rodless cavity oil pipe 34 and the telescopic oil pipe B32, and the piston rod of the front claw cylinder 28 drives the front conical push block 29 to move upwards. The front conical push block 29 drives the front claw 30 to retract in the ascending process, so that the clamping state of the front claw 30 and a well wall is relieved, after the front claw 30 is retracted in place, the flow distributor 4 presses an upper oil cavity of the telescopic oil cylinder 20 through the telescopic cylinder rodless cavity oil pipe 26 to push a piston rod of the telescopic oil cylinder 20 to descend, so that the telescopic head is driven to move forwards, after the piston rod of the telescopic oil cylinder 20 moves downwards in place, the flow distributor 4 presses an upper oil cavity of the front claw oil cylinder 28 through the front claw rod cavity oil pipe 33 and the telescopic oil pipe A31, and the piston rod of the front claw oil cylinder 28 drives the front conical push block 29 to move downwards, so that the front claw 30 is extruded out and the well wall is clamped again; then, the distributor 4 presses the lower oil cavity of the rear claw cylinder 19 through the rear claw cylinder rodless cavity oil pipe 24, so that the piston rod of the rear claw cylinder 19 drives the rear conical push block 21 to ascend, and the rear claw 22 is driven to retract in the process of ascending the rear conical push block 21, thereby releasing the clamping state of the rear claw 22 and the well wall.

After the rear claw 22 is retracted in place, the flow distributor 4 presses the lower oil cavity of the telescopic oil cylinder 20 through the rod cavity oil pipe 25 of the telescopic oil cylinder, and the piston rod of the telescopic oil cylinder 20 is pushed to retract again.

The telescopic underground tractor has the characteristics of simple structure, good practicability, high power, strong traction force and good stability, and effectively solves the problems of high underground friction resistance, difficult loading and unloading and difficult application of drilling pressure of the conventional tractor; the method is particularly suitable for pulling the coiled tubing in well workover, well completion and other operations.

Claims

1. The utility model provides a telescopic tractor in pit, it comprises top connection (1), shell (2), turbine axle (3), sloping cam plate hydraulic pump, join in marriage flow device (4), telescopic cylinder (20) and flexible head, its characterized in that: an upper joint (1) is arranged on the top of the shell (2) in a threaded manner, and a turbine shaft (3) is arranged in the shell (2) below the upper joint (1) through symmetrically arranged turbine bearings (5); a turbine assembly (6) is arranged on the turbine shaft (3) between the turbine bearings (5), a swash plate hydraulic pump is arranged in the casing (2) below the turbine shaft (3) through a hydraulic pump bearing (7), a flow distributor (4) is arranged in the casing (2) below the swash plate hydraulic pump, and the flow distributor (4) is communicated with the swash plate hydraulic pump; the swash plate hydraulic pump is connected with the turbine shaft (3); a rear claw oil cylinder (19) and a telescopic oil cylinder (20) are sequentially arranged in the shell (2) below the flow distributor (4), and the rear claw oil cylinder (19) and the telescopic oil cylinder (20) are respectively communicated with the flow distributor (4); a rear claw (22) is arranged on the shell (2) corresponding to the rear claw cylinder (19), one end of the rear claw (22) extends to the outer end of the shell (2), and the other end of the rear claw (22) is in sliding connection with the rear claw cylinder (19); a telescopic head is arranged below the shell (2) and is connected with a piston rod of the telescopic oil cylinder (20);

the swash plate hydraulic pump consists of a main shaft (8), a hydraulic pump swash plate (9), a hydraulic pump valve plate (10), a hydraulic pump cylinder body (11), a hydraulic pump plunger (12), a plunger spring (13), a hydraulic pump oil tank (14), an oil outlet pipe (15), an oil return pipe (16), an oil tank piston (17) and an oil tank spring (18), wherein the hydraulic pump oil tank (14) is arranged below the hydraulic pump cylinder body (11) through the hydraulic pump valve plate (10), the hydraulic pump plunger (12) is symmetrically and movably arranged on the hydraulic pump cylinder body (11) through the plunger spring (13), and the hydraulic pump plunger (12) is communicated with the hydraulic pump oil tank (14) through the hydraulic pump valve plate (10); a hydraulic pump swash plate (9) is arranged above the hydraulic pump plunger (12) through a main shaft (8), the hydraulic pump swash plate (9) is connected with the hydraulic pump plunger (12) in a sliding contact manner, and the main shaft (8) is fixedly connected with the turbine shaft (3); an oil tank piston (17) is arranged in the oil tank (14) of the hydraulic pump through an oil tank spring (18), an oil outlet pipe (15) is arranged at the central part of the oil tank piston (17), one end of the oil outlet pipe (15) is communicated with the oil distribution plate (10) of the hydraulic pump, the other end of the oil outlet pipe (15) is communicated with the flow distributor (4), and the flow distributor (4) is communicated with the oil tank (14) of the hydraulic pump through an oil return pipe (16);

the telescopic head comprises a shell (27), a front claw cylinder (28), a front conical push block (29) and a front claw (30), wherein the front claw cylinder (28) is fixedly arranged in the shell (27), the front conical push block (29) is arranged at the end head of a piston rod of the front claw cylinder (28), a clamping groove is formed in the front conical push block (29), the front claw (30) is arranged on the shell (27) corresponding to the front conical push block (29), one end of the front claw (30) extends to the outer end of the shell (27), a clamping head corresponding to the clamping groove is arranged at the end head of the other end of the front claw (30), the front conical push block (29) and the front claw (30) are connected in a matched sliding mode through the clamping groove and a telescopic cylinder piston rod of the telescopic cylinder (20).

2. A telescopic downhole tractor according to claim 1, wherein: the rear conical push block (21) is arranged at the end head of a piston rod of the rear claw cylinder (19), a clamping groove is formed in the rear conical push block (21), a clamping head is arranged at the end head of a rear claw (22) corresponding to the rear conical push block (21), the rear conical push block (21) and the rear claw (22) are in sliding connection through the clamping groove and the clamping head, and the rear claw cylinder (19) is communicated with the current distributor (4) through a rod cavity oil pipe (23) of the rear claw cylinder and a rod cavity-free oil pipe (24) of the rear claw cylinder.

3. A telescopic downhole tractor according to claim 1, wherein: the telescopic oil cylinder (20) is communicated with the flow distributor (4) through a telescopic cylinder rod cavity oil pipe (25) and a telescopic cylinder rod cavity-free oil pipe (26).

4. A telescopic downhole tractor according to claim 1, wherein: a telescopic oil pipe A (31) and a telescopic oil pipe B (32) are installed in a telescopic cylinder piston rod of a telescopic oil cylinder (20), one end of the telescopic oil pipe A (31) is communicated with a flow distributor (4) through a front claw rod cavity oil pipe (33), the other end of the telescopic oil pipe A (31) is communicated with an upper cavity of a front claw oil cylinder (28), one end of the telescopic oil pipe B (32) is communicated with the flow distributor (4) through a front claw rod-free cavity oil pipe (34), and the other end of the telescopic oil pipe B (32) is communicated with a lower cavity of the front claw oil cylinder (28).