CN220378232U

CN220378232U - Closed loop linkage control type underground electric cutting tool

Info

Publication number: CN220378232U
Application number: CN202321967481.4U
Authority: CN
Inventors: 宋文忠; 冯成; 李成龙; 巫江华; 徐长龙; 霍宝峰; 寇世锋; 王学林
Original assignee: China National Petroleum Corp; CNPC Xibu Drilling Engineering Co Ltd
Current assignee: China National Petroleum Corp; CNPC Xibu Drilling Engineering Co Ltd
Priority date: 2023-07-25
Filing date: 2023-07-25
Publication date: 2024-01-23
Anticipated expiration: 2033-07-25

Abstract

The utility model relates to the technical field of petroleum exploration, in particular to a closed-loop combined control type underground electric cutting tool which comprises a fixed shell, a driving mechanism, a rotary sleeve, a driving pull rod, a cutting blade and a tool rest assembly. The oil pipe inner wall cutting device is reasonable and compact in structure, the fixed shell is fixed on the inner side of an oil pipe when the oil pipe inner wall cutting device is used, the driving mechanism drives the transmission sleeve and the rotating sleeve to rotate when the driving mechanism acts, the driving pull rod and the tool rest assembly are driven to rotate when the rotating sleeve rotates, the cutting blade is driven to rotate when the tool rest assembly rotates, so that the cutting blade cuts the inner wall of the oil pipe, meanwhile, the driving screw sleeve is driven to move upwards in the fixed shell when the rotating sleeve rotates, the driving pull rod is driven to move upwards when the driving screw sleeve moves upwards, and the cutting blade realizes feeding operation through the tool rest assembly when the driving pull rod moves upwards, so that the cutting blade cuts the inner wall of the oil pipe with different thicknesses, and the oil pipe inner wall cutting device has the characteristics of safety, labor saving, simplicity and high efficiency.

Description

Closed loop linkage control type underground electric cutting tool

Technical Field

The utility model relates to the technical field of petroleum exploration, in particular to a closed-loop combined control type underground electric cutting tool.

Background

In oil exploration operations, stuck drilling is a common downhole event in the drilling process, and cutting of drilling tools is an important method for solving such an event. The cutting techniques currently in common use downhole are: abrasive jet cutting, mechanical cutter cutting, and focused blasting cutting. The former two have larger limitations and poorer timeliness, but the focused blasting cutting has the advantages of more and more strict control of initiating explosive devices, and particularly the construction is difficult and heavy abroad, so that a safe, quick and reliable cable-conveying mechanical cutting tool is urgently needed.

The cable mechanical cutting tool (WECT) newly introduced by the Harbert company is a high-precision cutting process which depends on underground cable transmission power and can be used for cutting well completion tools such as casing, drill pipes, oil pipes or underground packers. The GE company has introduced an electric cutter (DTET) for service in the China market for early years, but the GE company has basically exited the domestic market at present due to low success rate.

Currently, a downhole cutting tool designed by Zhonghai oil and caryophyllus corporation adopts a rotary shell to drive a tool bit similar to a lathe tool type to rotate, and the disadvantage of the design scheme is that the rotary shell needs relatively high rotating speed and is relatively unreliable in downhole operation. The downhole cutting tool designed by southwest petroleum university adopts a rotary shell and drives a cutter head similar to a milling cutter to rotate, and the cutter head autorotates for milling. The underground cutting tool scheme designed by the university of Wuhan is that the cutting action adopts a double-motor design mode, one drives the cutter head to rotate, and the other drives the cutter head to feed, so that the cutting failure can be caused when the two motors act uncoordinated. The feeding mechanism of the underground cutting tool designed in the victory oil field adopts a deflection mode, has a complex structure, is unreliable and has higher failure rate in the use process.

Disclosure of Invention

The utility model provides a closed-loop combined control type underground electric cutting tool, which overcomes the defects of the prior art and can effectively solve the problems of complex structure and high failure rate of the existing underground cutting tool.

The technical scheme of the utility model is realized by the following measures: the utility model provides a closed loop allies oneself with accuse formula electric cutting tool in pit, which comprises a fixed housing, actuating mechanism, the rotating sleeve, the drive pull rod, cutting blade and knife rest subassembly, actuating mechanism is fixed mounting in the inboard fixed housing upper portion, actuating mechanism's output shaft outside fixed mounting has the driving sleeve, driving sleeve outside fixed mounting has the rotating sleeve of upper portion suit in the fixed housing, rotating sleeve lower extreme along circumference interval distribution has two rectangle sliding holes that go up and down, every sliding hole upper portion all communicates with the rotating sleeve outside, every sliding hole is interior all slidable mounting has the drive pull rod that the lower extreme is located the rotating sleeve below, every drive pull rod upper portion outside all is equipped with the constant head tank, the inboard spiro union of fixed housing has the inboard card to locate the transmission swivel nut in the constant head tank, the rotating sleeve lower part is equipped with the drive pull rod and can make circular cutting blade radial movement and along with the knife rest subassembly of rotating sleeve synchronous rotation when reciprocating.

The following are further optimizations and/or improvements to the above-described inventive solution:

the cutter rest assembly can comprise a guide block, a front sliding block and a rear sliding block, wherein a front guide groove with a backward opening is formed in the rear side of the lower end of the front driving pull rod, the upper part of the front guide groove is inclined leftwards relative to the lower part, rear guide grooves which are identical in structure and symmetrically distributed with the front guide groove are formed in the front side of the lower end of the rear driving pull rod, a radial through lower limit hole is formed in the lower part of the rotary sleeve corresponding to the position between the two driving pull rods, the guide block with the lower end located below the rotary sleeve is slidably mounted in the radial direction in the lower limit hole, the front sliding block is fixedly arranged on the front side of the guide block and slidably mounted in the front guide groove, rear sliding blocks which are identical in structure and symmetrically distributed with the front sliding block are fixedly mounted in the rear guide groove, and the upper end of the cutting blade is detachably and fixedly mounted on the lower end of the guide block.

The tool rest assembly can further comprise a mounting seat, bearings, a driving screw and a locking nut, wherein an assembly hole which is penetrated up and down is formed in the upper end of the guide block corresponding to the position between the front sliding block and the rear sliding block, an end cover is fixedly arranged on the inner side of the lower end of the assembly hole, a plurality of bearings sleeved in the assembly hole are sequentially arranged on the upper end of the end cover from bottom to top, the lower end of the driving screw penetrates through all the bearings and the end cover and then is positioned below the guide block, the mounting seat fixedly mounted with the driving screw is arranged on the inner side of the end cover, a cutting blade is fixedly mounted on the outer side of the lower portion of the mounting seat, and the locking nut with the upper end in mutual contact with the lower end of the cutting blade is screwed on the outer side of the lower end of the driving screw.

The section of the transmission screw rod at the inner side of the mounting seat and the lower part of the bearing can be in a regular polygon, and a plurality of connecting keys are uniformly distributed on the outer side of the mounting seat and the inner side of the cutting blade along the circumference at intervals.

The left side of the lower part of the transmission sleeve corresponding to the position between the two driving pull rods can be provided with a rectangular mounting hole which is positioned below the fixed shell and is radially penetrated, the left side of the rotation sleeve corresponding to the position of the mounting hole is provided with a rectangular connecting hole which is radially penetrated, the upper part of the connecting hole is fixedly provided with a positioning block of which the right end is clamped on the upper part of the mounting hole, the lower end of the positioning block is provided with a spacing with the inner wall of the lower part of the mounting hole, the lower part of the positioning block is provided with a positioning screw hole, and an adjusting screw of which the lower end is in contact with the inner wall of the lower part of the connecting hole is screwed in the positioning screw hole.

The upper part of the rotary sleeve corresponding to the lower end position of the fixed shell can be provided with a first step surface, the inner side of the lower part of the fixed shell is fixedly provided with a limiting inner ring table, the inner side of the lower end of the fixed shell corresponding to the position between the lower end of the limiting inner ring table and the first step surface is fixedly provided with a positioning shaft sleeve coaxially sleeved on the outer side of the upper part of the rotary sleeve, and the lower end of the transmission screw sleeve is in contact with the upper end of the limiting inner ring table.

The outer side of the lower end of the adjusting screw can be provided with a plurality of radially-through dismounting holes at intervals along the circumference.

The outer side of the cutting blade is sleeved with a protective sleeve, the upper end of the protective sleeve and the outer side of the lower end of the rotary sleeve are detachably and fixedly installed together, and the protective sleeve is cylindrical with an opening at the upper end and a closed lower end.

The oil pipe inner wall cutting device is reasonable and compact in structure, the fixed shell is fixed on the inner side of an oil pipe when the oil pipe inner wall cutting device is used, the driving mechanism drives the transmission sleeve and the rotating sleeve to rotate when the driving mechanism acts, the driving pull rod and the tool rest assembly are driven to rotate when the rotating sleeve rotates, the cutting blade is driven to rotate when the tool rest assembly rotates, so that the cutting blade cuts the inner wall of the oil pipe, meanwhile, the driving screw sleeve is driven to move upwards in the fixed shell when the rotating sleeve rotates, the driving pull rod is driven to move upwards when the driving screw sleeve moves upwards, and the cutting blade realizes feeding operation through the tool rest assembly when the driving pull rod moves upwards, so that the cutting blade cuts the inner wall of the oil pipe with different thicknesses, and the oil pipe inner wall cutting device has the characteristics of safety, labor saving, simplicity and high efficiency.

Drawings

Fig. 1 is a schematic diagram of a front sectional structure of a first embodiment.

FIG. 2 is an enlarged schematic cross-sectional view of the structure at A-A in FIG. 1.

FIG. 3 is an enlarged schematic cross-sectional view of the structure at B-B in FIG. 1.

FIG. 4 is an enlarged schematic cross-sectional view of the structure at C-C in FIG. 1.

Fig. 5 is a schematic enlarged sectional view of the structure shown at D-D in fig. 1.

Fig. 6 is a schematic perspective view of the transmission screw sleeve and the driving rod in the first embodiment.

The codes in the drawings are respectively: 1 is a fixed shell, 2 is a driving mechanism, 3 is a rotating sleeve, 4 is a transmission sleeve, 5 is a driving pull rod, 6 is a cutting blade, 7 is a guide block, 8 is a front slider, 9 is a rear slider, 10 is a front guide groove, 11 is a rear guide groove, 12 is a mounting seat, 13 is a bearing, 14 is a transmission screw, 15 is a locking nut, 16 is an end cover, 17 is a connecting key, 18 is a positioning block, 19 is an adjusting screw, 20 is a limiting inner ring table, 21 is a first step surface, 22 is a positioning shaft sleeve, 23 is a dismounting hole, 24 is a protective sleeve, 25 is a transmission screw sleeve, 26 is an upper clamping groove, and 27 is a lower clamping groove.

Detailed Description

The present utility model is not limited by the following examples, and specific embodiments can be determined according to the technical scheme and practical situations of the present utility model.

In the present utility model, for convenience of description, the description of the relative positional relationship of each component is described according to the layout manner of fig. 1 of the specification, for example: the positional relationship of the front, rear, upper, lower, left, right, etc. is determined in accordance with the layout direction of the drawings of the specification.

The utility model is further described below with reference to examples and figures:

embodiment one: as shown in fig. 1 to 6, the closed-loop joint control type downhole electric cutting tool comprises a fixed shell 1, a driving mechanism 2, a rotating sleeve 3, a driving pull rod 5, a cutting blade 6 and a tool rest assembly, wherein the driving mechanism 2 is fixedly arranged on the inner side of the upper part of the fixed shell 1, a transmission sleeve 4 is fixedly arranged on the outer side of an output shaft of the driving mechanism 2, the rotating sleeve 3 is sleeved in the fixed shell 1 on the outer side of the transmission sleeve 4, two rectangular sliding holes which are vertically arranged at intervals are circumferentially distributed at the lower end of the rotating sleeve 3, the upper part of each sliding hole is communicated with the outer side of the rotating sleeve 3, the driving pull rod 5 with the lower end positioned below the rotating sleeve 3 is slidably arranged in each sliding hole, a positioning groove is formed in the outer side of the upper part of each driving pull rod 5, the inner side of the fixed shell 1 is connected with a transmission screw sleeve 25 which is clamped in the positioning groove, and the tool rest assembly which enables the circular cutting blade 6 to radially move and synchronously rotate along with the rotating sleeve 3 when the driving pull rod 5 moves up and down is arranged on the lower part of the rotating sleeve 3.

According to the requirement, the driving mechanism 2 is a currently known gear motor, the outer side surface of the driving pull rod 5 is an arc surface, an upper clamping groove 26 communicated with the inside and the outside and a lower clamping groove 27 communicated with the outside are respectively arranged on the upper end surface and the lower end surface of the transmission screw sleeve 25 corresponding to the position of each driving pull rod 5, the upper end of the driving pull rod 5 is clamped in the corresponding upper clamping groove 26 and lower clamping groove 27, namely, the upper part of the driving pull rod 5 corresponding to the position above the positioning groove is positioned in the upper clamping groove 26, and the lower part of the driving pull rod 5 corresponding to the position below the positioning groove is positioned in the lower clamping groove 26. When the oil pipe cutting device is used, the upper outer side of the upper part of the fixed shell 1 is uniformly provided with a plurality of elastic supporting arms along the circumference at intervals, or the upper end of the fixed shell 1 is connected with the existing known anchoring units, the fixed shell 1 can be fixed at the set position of the inner side of an oil pipe, the driving mechanism 2 drives the transmission sleeve 4 and the rotating sleeve 3 to rotate when in action, the driving pull rod 5 and the knife rest assembly are driven to rotate when the rotating sleeve 3 rotates, the knife rest assembly drives the cutting blade 6 to rotate, so that the cutting blade 6 cuts the inner wall of the oil pipe, meanwhile, the driving screw sleeve 25 is driven to move upwards in the fixed shell 1 when the rotating sleeve 3 rotates, the driving pull rod 5 is driven to move upwards, and the cutting blade 6 is driven to realize feeding operation when the driving pull rod 5 moves upwards, so that the cutting blade 6 cuts the inner wall of the oil pipe with different thicknesses.

The closed loop combined control type downhole electric cutting tool can be further optimized or/and improved according to actual needs:

embodiment two: as shown in fig. 1 and 4, the tool rest assembly includes a guide block 7, a front slider 8 and a rear slider 9, a front guide groove 10 with a backward opening is provided at the rear side of the lower end of the front driving pull rod 5, the upper part of the front guide groove 10 is inclined to the left with respect to the lower part, a rear guide groove 11 with the same structure as the front guide groove 10 and symmetrically distributed is provided at the front side of the lower end of the rear driving pull rod 5, a radially penetrating lower limit hole is provided at the lower part of the rotating sleeve 3 corresponding to the position between the two driving pull rods 5, a guide block 7 with the lower end below the rotating sleeve 3 is slidably mounted in the lower limit hole in the radial direction, a front slider 8 slidably mounted in the front guide groove 10 is fixed at the front side of the guide block 7, a rear slider 9 with the same structure as the front slider 8 and symmetrically distributed is slidably mounted in the rear guide groove 11, and the upper end of the cutting blade 6 is detachably and fixedly mounted at the lower end of the guide block 7.

When the output shaft of the driving mechanism 2 rotates, the rotating sleeve 3 is driven to rotate, the transmission screw sleeve 25 is driven to rotate when the rotating sleeve 3 rotates, the transmission screw sleeve 25 moves upwards along the inner wall of the fixed shell 1 in a spiral manner under the guiding action of the driving pull rod 5, the driving pull rod 5 is driven to move upwards along the sliding hole of the rotating sleeve 3 when the transmission screw sleeve 25 moves upwards, the front sliding block 8 and the rear sliding block 9 move downwards relative to the driving pull rod 5 when the driving pull rod 5 moves upwards, namely the front sliding block 8 presses the left inner wall of the front guide groove 10, the rear sliding block 9 presses the left inner wall of the rear guide groove, finally the guide block 7 slides leftwards in the lower limit hole, so that the cutting blade 6 is driven to move leftwards, radial feeding is realized, meanwhile, the output shaft of the driving mechanism 2 rotates, the rotating sleeve 3 and the guide block 7 are driven to rotate, the cutting blade 6 is driven to rotate finally, so that the cutting operation of an oil pipe is realized, and after cutting is finished, the output shaft of the driving mechanism 2 is controlled to rotate reversely, the driving pull rod 5 moves downwards, and the cutting blade 6 is driven to reset finally.

Embodiment III: as shown in fig. 1 and 4, the tool rest assembly further includes a mounting seat 12, bearings 13, a driving screw 14 and a locking nut 15, an assembly hole penetrating up and down is provided at the upper end of the guide block 7 corresponding to the position between the front slider 8 and the rear slider 9, an end cover 16 is fixedly mounted at the inner side of the lower end of the assembly hole, a plurality of bearings 13 sleeved in the assembly hole are sequentially mounted at the upper end of the end cover 16 from bottom to top, the lower end of the driving screw 14 passes through all the bearings 13 and the end cover 16 and then is located below the guide block 7, the mounting seat 12 fixedly mounted with the driving screw 14 is mounted at the inner side of the end cover 16, the cutting blade 6 is fixedly mounted at the outer side of the lower part of the mounting seat 12, and the locking nut 15 with the upper end in contact with the lower end of the cutting blade 6 is screwed at the outer side of the lower end of the driving screw 14. In use, with such an arrangement, the cutting blade 6 is easy to disassemble and maintain, the drive screw 14 rotates the cutting blade 6, and the bearing 13 is used to support and axially position the drive screw 14.

Embodiment four: as shown in fig. 1, 4 and 5, the section of the driving screw 14 at the inner side of the mounting seat 12 and the lower position of the bearing 13 is in a regular polygon, and a plurality of connecting keys 17 are uniformly distributed on the outer side of the mounting seat 12 and the inner side of the cutting blade 6 along the circumference at intervals. According to the demand, the drive screw 14 cross-section that mount pad 12 inboard and lie in below bearing 13 lower extreme position all is regular hexagon, and the mount pad 12 outside and cutting blade 6 inboard are along circumference interval equipartition have two cross-section to be circular connecting key 17, and the mount pad 12 outside and the cutting blade 6 inboard that correspond every connecting key 17 position all are equipped with the arc wall that can form the cross-section and be circular shape fixed orifices, and connecting key 17 installs in the fixed orifices. By this arrangement, the cutting blade 6 and the drive screw 14 can be driven synchronously during use.

Embodiment four: as an optimization of the above embodiment, as shown in fig. 1 and 3, a rectangular mounting hole which is located below the fixed casing 1 and radially penetrates through the left side of the lower portion of the transmission sleeve 4 corresponding to the position between the two driving pull rods 5 is provided, a rectangular upper limit hole which radially penetrates through the left side of the rotary sleeve 3 corresponding to the position of the mounting hole is provided, a positioning block 18 with the right end clamped on the upper portion of the mounting hole is fixedly mounted on the upper portion of the upper limit hole, a space is provided between the lower end of the positioning block 18 and the inner wall of the lower portion of the mounting hole, a positioning screw hole is provided at the lower portion of the positioning block 18, and an adjusting screw 19 with the lower end in contact with the inner wall of the lower portion of the mounting hole is screwed into the positioning screw hole. In the use, through such setting, can make the output shaft of rotating cover and actuating mechanism 2 rotate in step, when actuating mechanism 2's output shaft rotated, can drive the rotation and the radial feeding of cutting blade 6 through rotating cover 3 and drive pull rod 5 to realize the cutting operation of pipe wall.

Fifth embodiment: as shown in fig. 1, a first step surface 21 is provided on the upper portion of the rotating sleeve 3 corresponding to the lower end of the fixed housing 1, a limiting inner ring table 20 is fixed on the inner side of the lower portion of the fixed housing 1, a positioning shaft sleeve 22 coaxially sleeved on the outer side of the upper portion of the rotating sleeve 3 is fixed on the inner side of the lower end of the fixed housing 1 corresponding to the position between the lower end of the limiting inner ring table 20 and the first step surface 21, and the lower end of the transmission screw sleeve 25 is in contact with the upper end of the limiting inner ring table 20. The first step surface 21 is located above the upper limit hole as required. In the use, through setting up the inner ring platform, can play spacing effect to transmission swivel nut 25, make drive pull rod 5 and preceding slider 8, back slider 9 mutually separated after preventing that transmission swivel nut 25 from moving down, through setting up location axle sleeve 22, can improve the axiality when rotatory cover 3 and fixed shell 1 rotate, promote the precision of cutting blade 6 cutting pipe wall, can also reduce the wearing and tearing of fixed shell 1.

Example six: as an optimization of the above embodiment, as shown in fig. 1, a plurality of radially penetrating dismounting holes 23 are circumferentially distributed at intervals on the outer side of the lower end of the adjusting screw 19. In the use, through setting up dismouting hole 23, be convenient for insert dismouting pole in dismouting hole 23 internal rotation adjusting screw 19 to make the lower extreme of adjusting screw 19 and mounting hole lower part inner wall mutual contact, can avoid the output shaft of actuating mechanism 2 to take place the axial float with rotatory cover 3 and lead to the fact the destruction to cutting blade 6, can also promote cutting accuracy.

Embodiment seven: as shown in fig. 1, 4 and 5, the outer side of the cutting blade 6 is sleeved with a protective sleeve 24 with the upper end detachably and fixedly installed with the outer side of the lower end of the rotary sleeve 3, and the protective sleeve 24 is cylindrical with the upper end opened and the lower end closed. According to the requirement, the inner side of the upper end of the protective sleeve 24 and the outer side of the lower end of the rotary sleeve 3 are detachably and fixedly installed together through two connecting bolts distributed at intervals along the circumference. In use, the protective sleeve 24 protects the edge of the outside of the cutting blade 6 from impact damage during transport.

The technical characteristics form the embodiment of the utility model, have stronger adaptability and implementation effect, and can increase or decrease unnecessary technical characteristics according to actual needs so as to meet the requirements of different situations.

Claims

1. The utility model provides a closed loop allies oneself with accuse formula electric cutting tool in pit, a serial communication port comprises a fixed housing, actuating mechanism, the swivel, the drive pull rod, cutting blade and knife rest subassembly, actuating mechanism is fixed in the inboard fixed mounting in fixed housing upper portion, actuating mechanism's output shaft outside fixed mounting has the drive sleeve, drive sleeve outside fixed mounting has the swivel of upper portion suit in fixed housing, swivel lower extreme along circumference interval distribution has two rectangle sliding holes of orientation from top to bottom, every sliding hole upper portion all communicates with the swivel outside, all slidable mounting has the drive pull rod that the lower extreme is located the swivel below in every sliding hole, every drive pull rod upper portion outside all is equipped with the constant head tank, the inboard spiro union of fixed housing has the inboard card to locate the transmission swivel in the constant head tank, the swivel lower part is equipped with the drive pull rod and can make circular cutting blade radial movement and with the knife rest subassembly of swivel synchronous rotation.

2. The closed loop combined control type downhole electric cutting tool according to claim 1, wherein the tool rest assembly comprises a guide block, a front sliding block and a rear sliding block, a front guide groove with a backward opening is formed in the rear side of the lower end of the front driving pull rod, the upper portion of the front guide groove is inclined leftwards relative to the lower portion, rear guide grooves which are identical in structure with the front guide groove and are symmetrically distributed are formed in the front side of the lower end of the rear driving pull rod, a lower limit hole which is radially communicated is formed in the lower portion of the rotary sleeve corresponding to the position between the two driving pull rods, a guide block with the lower end located below the rotary sleeve is slidably mounted in the lower limit hole in the radial direction, the front sliding block is fixedly arranged on the front side of the guide block and is slidably mounted in the front guide groove, a rear sliding block which is identical in structure with the front sliding block and is symmetrically distributed is slidably mounted in the rear guide groove, and the upper end of the cutting blade is detachably and fixedly mounted on the lower end of the guide block.

3. The closed-loop combined control type downhole electric cutting tool according to claim 2, wherein the tool rest assembly further comprises a mounting seat, bearings, a transmission screw and a locking nut, wherein an assembly hole which is penetrated up and down is formed in the upper end of a guide block corresponding to the position between the front sliding block and the rear sliding block, an end cover is fixedly arranged on the inner side of the lower end of the assembly hole, a plurality of bearings sleeved in the assembly hole are sequentially arranged on the upper end of the end cover from bottom to top, the lower end of the transmission screw passes through all the bearings and the end cover and then is positioned below the guide block, the mounting seat fixedly arranged together with the transmission screw is arranged on the inner side of the end cover, the cutting blade is fixedly arranged on the outer side of the lower part of the mounting seat, and the locking nut of which the upper end is mutually contacted with the lower end of the cutting blade is in a threaded manner on the outer side of the lower end of the transmission screw.

4. The closed-loop combined control type underground electric cutting tool according to claim 3, wherein the cross section of the transmission screw at the inner side of the mounting seat and the lower position of the bearing is in a regular polygon, and a plurality of connecting keys are uniformly distributed on the outer side of the mounting seat and the inner side of the cutting blade along the circumference at intervals.

5. The closed-loop combined control type downhole electric cutting tool according to claim 1, 2, 3 or 4, wherein a rectangular mounting hole which is positioned below the fixed shell and is radially penetrated is arranged on the left side of the lower part of the transmission sleeve corresponding to the position between the two driving pull rods, a rectangular connecting hole which is radially penetrated is arranged on the left side of the rotating sleeve corresponding to the position of the mounting hole, a positioning block with the right end clamped on the upper part of the mounting hole is fixedly arranged on the upper part of the connecting hole, a space is arranged between the lower end of the positioning block and the inner wall of the lower part of the mounting hole, a positioning screw hole is arranged on the lower part of the positioning block, and an adjusting screw with the lower end contacted with the inner wall of the lower part of the connecting hole is screwed in the positioning screw hole.

6. The closed loop combined control type downhole electric cutting tool according to claim 5, wherein the upper part of the rotary sleeve corresponding to the lower end position of the fixed housing is provided with a first step surface, a limiting inner ring table is fixed on the inner side of the lower part of the fixed housing, a positioning shaft sleeve coaxially sleeved on the outer side of the upper part of the rotary sleeve is fixed on the inner side of the lower end of the fixed housing corresponding to the position between the lower end of the limiting inner ring table and the first step surface, and the lower end of the transmission screw sleeve is in contact with the upper end of the limiting inner ring table.

7. The closed-loop, coordinated control type downhole electric cutting tool of claim 5, wherein a plurality of radially penetrating dismounting holes are circumferentially spaced outside the lower end of the adjusting screw.

8. The closed-loop, coordinated control type downhole electric cutting tool of claim 6, wherein a plurality of radially penetrating dismounting holes are circumferentially spaced outside the lower end of the adjusting screw.

9. The closed loop, coordinated control type downhole electric cutting tool according to claim 1 or 2 or 3 or 4 or 6 or 7 or 8, wherein the outer side of the cutting blade is sleeved with a protective sleeve with the upper end detachably and fixedly installed with the outer side of the lower end of the rotary sleeve, and the protective sleeve is in a cylinder shape with the upper end open and the lower end closed.

10. The closed loop, coupled control type downhole electric cutting tool as claimed in claim 5, wherein the outer side of the cutting blade is sleeved with a protective sleeve having an upper end detachably and fixedly mounted with the outer side of the lower end of the rotary sleeve, and the protective sleeve is in a cylindrical shape with an upper end opening and a lower end closed.