An electrically powered power system for a downhole oil casing cutting tool

Abstract

The application relates to the technical field of oil drilling and workover tools, and provides a power system of an electrically-driven downhole oil casing cutting tool, which comprises an upper shell, a revolving shell and a lower shell which are independently coaxially rotatably connected in sequence; a revolving motor is fixedly installed in the upper shell, and a high-speed motor is fixedly installed in the lower shell; the output shaft of the revolving motor drives the revolving shell to rotate; a cutter is eccentrically installed on a cutting shaft relative to the axial line of the revolving shell; the output shaft of the revolving motor also drives the cutting shaft to displace along an arc path into the revolving shell through a clutch rod; and the output shaft of the high-speed motor drives the cutting shaft to rotate through multi-stage transmission. The revolving shell and the clutch rod and other structural settings enable the low-speed revolving motor and the high-speed motor to work cooperatively to drive the cutter to rotate, revolve and retract and extend; the structure is compact and reliable, the transmission is clear and stable, the operation is easy, and the structure is convenient for later maintenance; the full-electric control operation can be realized, and the operation can be automated.

Description

Technical Field

[0001] This invention relates to an electrically driven power system for downhole casing cutting tools, belonging to the technical field of oil drilling and well workover tools. Background Technology

[0002] Due to human factors, formation compression, oil and gas corrosion, etc., downhole tubing and casing may deform, break, or perforate, requiring cutting and replacement. Traditional cutting methods use mechanical or hydraulic cutters, which have many drawbacks. To address these drawbacks, the inventors of this invention designed a purely electrically driven downhole tubing and casing cutting tool to solve the above problems. However, in addition to using a motor to drive the cutter to rotate and complete the cutting, the purely electrically driven downhole tubing and casing cutting tool also needs to drive the cutter to revolve around the circumference to complete the cutting of the downhole tubing and casing. Furthermore, the issue of cutting tool retraction and extension must be considered. Existing technologies have failed to provide an effective solution to these requirements. Summary of the Invention

[0003] To solve the above-mentioned technical problems, the present invention provides an electrically driven downhole casing and tubing cutting tool power system. The electrically driven downhole casing and tubing cutting tool power system is designed with a rotating housing and a clutch rod, which enables a low-speed rotating motor and a high-speed high-speed motor to work together to drive the cutting tool to rotate for cutting, rotate around the circumference, and extend and retract.

[0004] The present invention is achieved through the following technical solutions.

[0005] This invention provides an electrically driven downhole casing cutting tool power system, comprising an upper housing, a central housing, and a lower housing that are rotatably and independently coaxially connected in sequence; a central housing motor is fixedly installed inside the upper housing, and a high-speed motor is fixedly installed inside the lower housing; the output shaft of the central housing motor drives the central housing to rotate, and a cutting blade is eccentrically mounted on the cutting shaft relative to the axis of the central housing; the output shaft of the central housing motor also drives the cutting shaft to move along an arc path into the central housing through a clutch rod, and the output shaft of the high-speed motor drives the cutting shaft to rotate through multi-stage transmission.

[0006] The revolution motor is fixedly mounted on the upper mounting bracket, which is fixed to the upper housing; the high-speed motor is fixedly mounted on the lower mounting bracket, which is fixed to the lower housing.

[0007] The inner wall between the upper shell and the orbital shell is provided with a first mating liner, and ball bearings are arranged circumferentially between the upper shell and the first mating liner, and between the orbital shell and the first mating liner.

[0008] The inner wall between the orbital shell and the lower shell is provided with a lower mating liner, and ball bearings are arranged circumferentially between the orbital shell and the lower mating liner, and between the lower shell and the lower mating liner.

[0009] The rotating motor shaft coaxially drives the drive shaft, the middle section of the drive shaft meshes with the rotating gears, and the outer ring of the rotating gears meshes with the rotating housing.

[0010] The rotating motor shaft coaxially drives the drive shaft, and the lower end of the drive shaft engages with the drive gear for retracting and extending. The drive gear is fitted onto the end of the clutch rod. The rotation of the clutch rod drives the cutter disc to rotate relative to the axis of the clutch rod. The cutter disc is mounted on the cutter shaft, which is rotatably mounted on the end of the cutting shaft. The clutch rod can be electrically controlled to separate and rotate.

[0011] The cutting shaft is installed through a semi-circular arc groove on the guide plate. The guide plate is fixed to the orbital housing. The arc end points of the semi-circular arc groove are located at the outer edge of the guide plate and the axis of the guide plate, respectively.

[0012] The cutter support disc extends to a position close to the guide plate and is clearance-fitted with the guide plate. A fixing plate is fixed on the cutter support disc, and the cutting shaft passes through the fixing plate and is rotatably installed via ball bearings.

[0013] The output shaft of the high-speed motor is connected to a transmission stabilizing shaft, which is rotatably fixed to the lower housing. The stabilizing shaft meshes with the high-speed shaft, which in turn meshes with the cutting shaft. The axis of the high-speed shaft coincides with that of the clutch lever.

[0014] Slip rings are also fixedly installed on the upper and lower mounting brackets. A conduit passes through the rotating housing for wiring and connecting the rotating and non-rotating circuits to prevent the circuit from getting tangled.

[0015] The beneficial effects of this invention are as follows: through the structural design of the orbital housing and clutch rod, the low-speed orbital motor and the high-speed motor can work together to drive the tool to rotate for cutting, circumferential revolution and retraction; the structure is compact and reliable, the transmission is clear and stable, it is easy to operate and easy to maintain; it is easy to realize fully electric control operation and can be automated. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the upper structure of at least one embodiment of the present invention;

[0017] Figure 2 yes Figure 1 A front view structural diagram of the center guide plate;

[0018] Figure 3 yes Figure 1 The corresponding lower structure diagram.

[0019] In the diagram: 11-Upper housing, 12-Revolution housing, 13-Lower housing, 14-First docking liner, 15-Lower docking liner, 16-Ball bearing, 17-Upper mounting bracket, 18-Lower mounting bracket, 19-Slip ring, 21-Revolution motor, 22-Drive shaft, 23-Revolution gear, 24-Retraction and release driven gear, 25-Tool holder, 26-Tool holder shaft, 27-Fixed plate, 28-Guide plate, 29-Clutch rod, 31-High-speed motor, 32-Output shaft, 33-Stabilizing shaft, 34-High-speed shaft, 35-Blade, 36-Cutting shaft. Detailed Implementation

[0020] The technical solution of the present invention is further described below, but the scope of protection is not limited to what is described.

[0021] The first embodiment of the present invention relates to, for example Figures 1 to 3 The power system of an electrically driven downhole casing cutting tool shown includes an upper housing 11, a revolving housing 12, and a lower housing 13 that are rotatably and coaxially connected in sequence. A revolving motor 21 is fixedly installed inside the upper housing 11, and a high-speed motor 31 is fixedly installed inside the lower housing 13. The output shaft of the revolving motor 21 drives the revolving housing 12 to rotate. A blade 35 is eccentrically mounted on a cutting shaft 36 relative to the axis of the revolving housing 12. The output shaft of the revolving motor 21 also drives the cutting shaft 36 to move along an arc path into the revolving housing 12 through a clutch rod 29. The output shaft of the high-speed motor 31 drives the cutting shaft 36 to rotate through multi-stage transmission.

[0022] Therefore, the revolution motor 21 is used to drive the blade 35 to revolve and retract synchronously without interfering with each other, and the high-speed motor 31 is used to drive the blade 35 to rotate to achieve blade cutting. After retraction and extension, under the action of the clutch rod 29, the revolution motor 21 is only used to drive the blade to revolve. Thus, with an extremely compact structure, all the core cutting requirements of the tool for cutting downhole oil casing can be met.

[0023] The second embodiment of the present invention is largely the same as the first embodiment, mainly in the preferred scheme of motor installation and wiring. The revolution motor 21 is fixedly installed on the upper mounting bracket 17, which is fixed to the upper housing 11; the high-speed motor 31 is fixedly installed on the lower mounting bracket 18, which is fixed to the lower housing 13.

[0024] Furthermore, slip rings 19 are fixedly installed on the upper mounting bracket 17 and the lower mounting bracket 18, and conduits for circuit wiring pass through the orbital housing 12.

[0025] Therefore, the mounting bracket ensures that the two motors are securely fixed and their wiring is properly connected.

[0026] The third embodiment of the present invention is largely the same as the first embodiment, mainly in achieving a preferred scheme for rotatable connection between the shells. The inner wall between the upper shell 11 and the revolving shell 12 has a first mating liner 14, and ball bearings 16 are arranged circumferentially between the upper shell 11 and the first mating liner 14, and between the revolving shell 12 and the first mating liner 14.

[0027] Furthermore, there is a lower mating liner 15 on the inner wall between the orbital shell 12 and the lower shell 13, and ball bearings 16 are arranged circumferentially between the orbital shell 12 and the lower mating liner 15, and between the lower shell 13 and the lower mating liner 15.

[0028] Generally, the upper housing 11 and the lower housing 13 can be integrally set or relatively fixed. When the upper housing 11 and the lower housing 13 are not fixed, since a high-speed motor is installed in the lower housing 13, and the upper housing 11 and the lower housing 13 may rotate relative to each other based on the rotation of the orbital housing 12, the power source is the orbital motor, and the rotation speed is slow, so it has basically no impact on the high-speed rotational cutting of the blade 35.

[0029] The fourth embodiment of the present invention is largely the same as the first embodiment, mainly in the preferred structure for the revolution motor and the high-speed motor to achieve the coordinated operation of revolution and blade retraction. The end of the revolution motor 21 coaxially drives the drive shaft 22, the middle section of the drive shaft 22 meshes with the revolution gear 23, and the outer ring of the revolution gear 23 meshes with the revolution housing 12.

[0030] Furthermore, the shaft end of the revolution motor 21 coaxially drives the drive shaft 22, and the lower end of the drive shaft 22 engages with the drive gear 24 for winding and unwinding. The drive gear 24 is fitted onto the end of the clutch rod 29. The rotation of the clutch rod 29 drives the cutter support disc 25 to rotate relative to the axis of the clutch rod 29. The cutter support disc 25 is mounted on the cutter support shaft 26, and the cutter support shaft 26 is rotatably mounted on the end of the cutting shaft 36. The clutch rod 29 can be electrically controlled to separate and rotate.

[0031] Furthermore, the cutting shaft 36 is installed through the semi-circular arc groove on the guide plate 28. The guide plate 28 is fixed to the orbital housing 12. The arc end points of the semi-circular arc groove are located at the outer edge of the guide plate 28 and the axis of the guide plate 28, respectively.

[0032] Furthermore, the cutter holder 25 extends to a position close to the guide plate 28 and is clearance-fitted with the guide plate 28. A fixing plate 27 is fixed on the cutter holder 25, and the cutting shaft 36 passes through the fixing plate 27 and is rotatably mounted via a ball bearing.

[0033] Furthermore, the output shaft 32 of the high-speed motor 31 is connected to the transmission stabilizing shaft 33, which is rotatably fixed to the lower housing 13; the stabilizing shaft 33 engages with the transmission high-speed shaft 34, and the high-speed shaft 34 engages with the transmission cutting shaft 36; the high-speed shaft 34 coincides with the axis of the clutch lever 29.

Claims

1. A power system for an electrically driven downhole casing cutting tool, comprising an upper housing (11), a revolving housing (12), and a lower housing (13) that are sequentially and independently coaxially rotatably connected, characterized in that: A revolution motor (21) is fixedly installed inside the upper housing (11), and a high-speed motor (31) is fixedly installed inside the lower housing (13). The output shaft of the revolution motor (21) drives the revolution housing (12) to rotate. A blade (35) is eccentrically mounted on the cutting shaft (36) relative to the axis of the revolution housing (12). The output shaft of the revolution motor (21) also drives the cutting shaft (36) to move along an arc path into the revolution housing (12) through a clutch rod (29). The output shaft of the high-speed motor (31) has multi-stage transmission. The cutting shaft (36) is driven to rotate; the end of the revolving motor (21) coaxially drives the drive shaft (22), the lower end of the drive shaft (22) meshes with the passive gear (24), the passive gear (24) is fitted on the end of the clutch rod (29), the clutch rod (29) rotates and drives the knife support disc (25) to rotate relative to the axis of the clutch rod (29), the knife support disc (25) is mounted on the knife support shaft (26), the knife support shaft (26) can be rotatably mounted on the end of the cutting shaft (36); the clutch rod (29) can be electrically controlled to separate and rotate.

2. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The revolution motor (21) is fixedly mounted on the upper mounting bracket (17), which is fixed to the upper housing (11); the high-speed motor (31) is fixedly mounted on the lower mounting bracket (18), which is fixed to the lower housing (13).

3. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The inner wall between the upper shell (11) and the orbital shell (12) has a first mating liner (14), and ball bearings (16) are arranged around the circumference between the upper shell (11) and the first mating liner (14) and between the orbital shell (12) and the first mating liner (14).

4. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The inner wall between the orbital shell (12) and the lower shell (13) is provided with a lower mating liner (15), and ball bearings (16) are arranged around the circumference between the orbital shell (12) and the lower mating liner (15) and between the lower shell (13) and the lower mating liner (15).

5. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The rotating motor (21) drives the drive shaft (22) coaxially at the shaft end. The middle section of the drive shaft (22) meshes with the rotating gear (23), and the outer ring of the rotating gear (23) meshes with the rotating housing (12).

6. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The cutting shaft (36) is installed through the semi-circular arc groove on the guide plate (28). The guide plate (28) is fixed to the orbital housing (12). The arc end points of the semi-circular arc groove are located at the outer edge of the guide plate (28) and the axis of the guide plate (28), respectively.

7. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The cutter holder (25) extends to a position close to the guide plate (28) and is clearance-fitted with the guide plate (28). A fixing plate (27) is fixed on the cutter holder (25), and the cutting shaft (36) passes through the fixing plate (27) and is rotatably mounted by ball bearings.

8. The power system for the electrically driven downhole casing cutting tool as described in claim 1, characterized in that: The output shaft (32) of the high-speed motor (31) is connected to the transmission stabilizing shaft (33), which is rotatably fixed to the lower housing (13); the stabilizing shaft (33) meshes with the transmission high-speed shaft (34), which meshes with the transmission cutting shaft (36); the high-speed shaft (34) coincides with the axis of the clutch rod (29).

9. The power system for the electrically driven downhole casing cutting tool as described in claim 2, characterized in that: Slip rings (19) are also fixedly installed on the upper mounting bracket (17) and the lower mounting bracket (18), and a wire pipe is fixedly installed through the orbital housing (12) for circuit wiring.

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