Downhole rotary jet cutting tool and assembling method and working method thereof

Abstract

The invention discloses an underground rotary jet cutting tool and an assembling method and a working method thereof, the tool is composed of an impeller assembly, a transmission device, a jet device and the like, the impeller assembly is composed of a fixed impeller and a movable impeller, and the transmission device is composed of a transmission sleeve, a transmission rod, a speed reducer and the like. According to the downhole rotary jet cutting tool, a large shaft hole tolerance gap is adopted, the sealing friction resistance in the high-frequency relative movement process of the impeller, the transmission shaft and the outer cylinder is better reduced, the jamming situation caused by the fact that tiny rock debris particles enter the shaft hole tolerance gap is greatly reduced, meanwhile, abrasion of a sealing piece is reduced, and the service life is remarkably prolonged; and a speed reducer structure is used for balancing the impeller rotating speed and the rotating nozzle output rotating speed.

Description

Technical Field

[0001] This invention relates to the field of downhole tools technology for oil drilling and production, and in particular to a downhole rotary jet cutting tool, its assembly method, and its operating method. Background Technology

[0002] With the increasing age of oil wells, the growing number of extended reach wells, and the continuous extension of horizontal displacement, well workover, fishing, and well washing operations face greater challenges. The downhole rotary jet cutting tool offers a simple and effective solution to this problem, providing a unique and efficient approach. This tool uses high-pressure hydraulic jets, matched with different nozzles, to cut down fish, fish in sections, or perform high-pressure jet well washing.

[0003] However, the commonly used downhole rotary jet cutting tools are mainly constrained by the following issues: (1) The impeller clearance is too large, which can easily lead to erosion and leakage. (2) The clearance is too small, which leads to high friction of the rotating device and can easily cause small particles in the mud to get stuck, resulting in tool failure. (3) The nozzle material and structure design are unreasonable, which can easily cause erosion and tool failure. (4) The wear-resistant seals are incompatible with the complex chemical components and high temperature in oil-based mud, resulting in rapid seal failure, which shortens the working time of the tool in the well. (5) Conventional rotary jet tools are driven by liquid to rotate the nozzle (the nozzle has an inclined nozzle). Due to the inclined nozzle, the high-pressure jet cannot continuously act on the object being cut, resulting in low efficiency.

[0004] In summary, existing downhole rotary jet cutting tools generally suffer from serious defects such as jamming, high friction, high wear, poor chemical resistance, poor high temperature resistance, and poor high pressure resistance, resulting in poor field application performance. Summary of the Invention

[0005] The purpose of this invention is to provide a downhole rotary jet cutting tool and its assembly and operation methods.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A downhole rotary jet cutting tool includes an upper connector, the lower male end of which is connected to the upper female end of an outer cylinder. The outer cylinder contains a filter screen and an impeller assembly. The impeller assembly includes a balance bar, a fixed impeller, and a moving impeller. The bottom end of the upper connector engages with the filter screen via a spline, and the bottom end of the filter screen engages with the impeller assembly via a spline. The lower end of the balance bar passes through the fixed impeller and into the moving impeller, connecting to a first locking screw. The lower end of the moving impeller is connected to a transmission rod. A deep groove ball bearing is mounted on the outer wall of the thin shaft portion of the transmission rod, and a transmission sleeve is provided at the outer diameter of the deep groove ball bearing. The lower end is splined into the reducer, the bottom of the reducer is connected to the flow plate, the center of the bottom end of the reducer extends into the inner hole of the flow plate and is connected to the splined drive rod, the lower end of the splined drive rod is splined into the drive spindle, the upper outer surface of the splined drive rod and the drive spindle is fitted with a connecting short section, the upper male end of the connecting short section is connected to the lower female end of the outer cylinder, the lower male end of the connecting short section is connected to the upper female end of the balance outer cylinder, the drive spindle passes through the balance outer cylinder and is connected to the nozzle, and a tapered roller bearing is provided between the outer wall surface of the drive spindle and the inner wall surface of the balance outer cylinder.

[0008] Furthermore, the bottom surface of the moving impeller is provided with a groove, and the top surface of the transmission rod is provided with a protrusion, the groove and the protrusion being adapted to each other.

[0009] Furthermore, the flow plate is connected to the reducer via a second set screw.

[0010] Furthermore, a first O-ring is provided at the connection between the upper connector and the outer cylinder.

[0011] Furthermore, a steel ball groove is provided on the mating surface between the fixed impeller and the balance bar, and the steel ball groove is filled with steel balls.

[0012] Furthermore, the outer wall of the reducer is connected to the transmission sleeve by a second set screw.

[0013] Furthermore, a first O-ring is provided at the connection between the outer cylinder and the connecting short section, and a first O-ring is provided at the connection between the connecting short section and the balancing outer cylinder.

[0014] Furthermore, a second O-ring is provided at the connection between the drive spindle and the nozzle.

[0015] The assembly method of the downhole rotary jet cutting tool of the present invention includes the following steps:

[0016] The impeller assembly is installed on the left side of the outer cylinder. The balance bar in the impeller assembly is on the left side, and the fixed impeller is in the middle. The two are engaged by splines. Then the moving impeller is assembled.

[0017] The filter screen and the upper connector are installed sequentially on the left side of the outer cylinder. The upper connector, filter screen and impeller assembly are engaged by splines.

[0018] Install the deep groove ball bearing into the thin shaft end of the transmission rod, and then place the transmission sleeve on the outer diameter of the deep groove ball bearing.

[0019] The transmission rod is installed from the right side of the outer cylinder. There is a steel ball groove at the joint between the fixed impeller and the balance bar, and the groove is filled with steel balls.

[0020] Install the speed reducer, which engages with the spline on the right side of the transmission rod.

[0021] Install the flow plate, which is connected to the reducer via the second set screw;

[0022] Insert the splined drive rod from the right side of the outer cylinder and connect it to the reducer;

[0023] Install the connecting short section on the right side of the outer cylinder;

[0024] A tapered roller bearing is installed on each of the left and right sides of the transmission spindle;

[0025] The assembled drive spindle is inserted into the connecting short section and connected to the spline drive rod via a spline.

[0026] Connect the outer balance cylinder through the drive spindle and to the connecting short section;

[0027] Connect the nozzle to the drive spindle.

[0028] The working method of the downhole rotary jet cutting tool of the present invention is as follows: liquid enters the fixed impeller and the moving impeller through the filter screen, the impeller generates high-speed rotation, the rotation is transmitted to the reducer through the balance bar and the transmission bar, the reducer outputs the input high-speed, low-torque rotation as uniform speed, low speed, high torque rotation through the internal reduction device, and the rotation is transmitted to the nozzle through each spindle, thereby the nozzle rotates;

[0029] Liquid is ejected through nozzles inside the nozzle. The force of liquid injection is determined by adjusting the nozzle diameter according to different tasks, thereby achieving jet cutting and well washing operations.

[0030] The technical principle of the downhole rotary jet cutting tool of the present invention is as follows: the liquid flows through the impeller assembly to generate rotational torque, which is transmitted to the nozzle through the reducer and transmission rod. The nozzle has a throttling nozzle, and the liquid is ejected from the nozzle, thereby generating rotary jet.

[0031] Compared with the prior art, the outstanding effect of the present invention is as follows:

[0032] (1) The downhole rotary jet cutting tool of the present invention is mainly used for fishing, hydraulic cutting, high-pressure jet well washing and other operations during oil drilling and well workover. During drilling / workover, when the head of the fish that has fallen is irregular and the fishing tool cannot catch the fish, the downhole rotary jet cutting tool of the present invention can be used to trim the head of the fish; or when the part of the fish that has not been stuck cannot be pulled out by inverting, the downhole rotary jet cutting tool of the present invention can be used to cut the fish and fish it out in sections; or when the fish is seriously buried in sand during well workover, and ordinary circulation cannot circulate the sand out of the wellbore, the tool of the present invention can be used to circulate and wash the well with high-pressure jet.

[0033] (2) The tool of the present invention adopts a larger shaft hole tolerance clearance, which is more conducive to reducing the sealing friction resistance during the high-frequency relative motion of the impeller, drive shaft and outer cylinder, greatly reducing the jamming caused by the entry of small rock chips into the shaft hole tolerance clearance, while reducing the wear of the seals and significantly improving the service life; and uses a speed reducer structure to balance the impeller speed and the output speed of the rotating nozzle.

[0034] The following description, in conjunction with the accompanying drawings and specific embodiments, further illustrates the downhole rotary jet cutting tool, its assembly method, and its working method according to the present invention. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of a downhole rotary jet cutting tool.

[0036] Among them, 1-upper connector, 2-filter screen, 3-outer cylinder, 4-balance bar, 5-fixed impeller, 6-moving impeller, 7-transmission rod, 8-transmission sleeve, 9-flow plate, 10-spline transmission rod, 11-connecting short section, 12-balanced outer cylinder, 13-transmission mandrel, 14-nozzle, 15-steel ball, 16-first set screw, 17-deep groove ball bearing, 18-second set screw, 19-tapered roller bearing, 20-first O-ring, 21-second O-ring, 22-reducer. Detailed Implementation

[0037] like Figure 1 As shown ( Figure 1(The left side represents the top, and the right side represents the bottom). A downhole rotary jet cutting tool includes an upper connector 1. The lower male end of the upper connector 1 is connected to the upper female end of the outer cylinder 3. The outer cylinder 3 is equipped with a filter screen 2 and an impeller assembly. The impeller assembly includes a balance bar 4, a fixed impeller 5, and a moving impeller 6. The bottom end of the upper connector 1 is splined to the filter screen 2, and the bottom end of the filter screen 2 is splined to the impeller assembly. The lower end of the balance bar 4 passes through the fixed impeller 5 and into the moving impeller 6, and is connected to a first locking screw 16. The lower end of the moving impeller 6 is connected to a transmission rod 7. A deep groove ball bearing 17 is mounted on the outer wall of the thin shaft portion of the transmission rod 7. A transmission sleeve 8 is provided at the outer diameter of the deep groove ball bearing 17. The transmission rod 7... The lower end of the nozzle is splined to the reducer 22. The bottom of the reducer 22 is connected to the flow plate 9. The center of the bottom end of the reducer 22 extends into the inner hole of the flow plate 9 and is connected to the splined transmission rod 10. The lower end of the splined transmission rod 10 is splined to the transmission spindle 13. A connecting short section 11 is sleeved on the upper outer side of the splined transmission rod 10 and the transmission spindle 13. The upper male end of the connecting short section 11 is connected to the lower female end of the outer cylinder 3. The lower male end of the connecting short section 11 is connected to the upper female end of the balance outer cylinder 12. The transmission spindle 13 passes through the balance outer cylinder 12 and is connected to the nozzle 14. A tapered roller bearing 19 is provided between the outer wall surface of the transmission spindle 13 and the inner wall surface of the balance outer cylinder 12.

[0038] The bottom surface of the impeller 6 is provided with a groove, and the top surface of the transmission rod 7 is provided with a protrusion, and the groove and the protrusion are adapted to each other.

[0039] The flow plate 9 is connected to the reducer 22 by the second tightening screw 18.

[0040] A first O-ring 20 is provided at the connection between the upper connector 1 and the outer cylinder 3.

[0041] A ball groove is provided on the mating surface between the fixed impeller 5 and the balance bar 4, and the ball groove is filled with steel balls 15.

[0042] The outer wall of the reducer 22 is connected to the transmission sleeve 8 by the second fastening screw 18.

[0043] A first O-ring 20 is provided at the connection between the outer cylinder 3 and the connecting short section 11, and a first O-ring 20 is provided at the connection between the connecting short section 11 and the balance outer cylinder 12.

[0044] A second O-ring 21 is provided at the connection between the drive spindle 13 and the nozzle 14.

[0045] The assembly method of this downhole rotary jet cutting tool includes the following steps:

[0046] The impeller assembly is installed on the left side of the outer cylinder 3. The balance bar 4 in the impeller assembly is on the left side, and the fixed impeller 5 is in the middle. The two are engaged by splines. Then the moving impeller 6 is freely assembled (the moving impeller has a foolproof assembly setting, and it cannot be assembled in the opposite direction).

[0047] Filter screen 2 and upper connector 1 are installed sequentially on the left side of the outer cylinder. Upper connector 1, filter screen 2 and impeller assembly are engaged by splines.

[0048] Install the deep groove ball bearing 17 into the thin shaft end of the transmission rod 7 (the assembly does not distinguish between the right and wrong directions), and put the transmission sleeve 8 on the outer diameter of the deep groove ball bearing.

[0049] Insert the transmission rod 7 from the right side of the outer cylinder 3 (the end with the protrusion faces inward and matches the groove of the moving impeller). There is a steel ball groove at the point where the fixed impeller 5 matches the balance bar 4, and the groove is filled with steel balls 15.

[0050] Install the reducer 22, which engages with the spline on the right side of the transmission rod 7;

[0051] Install the flow plate 9, which is connected to the reducer 22 via the second fastening screw 18;

[0052] Insert the splined transmission rod 10 from the right side of the outer cylinder 3 and connect it to the reducer 22;

[0053] Insert the connecting short section 11 into the right side of the outer cylinder 3 (the smaller inner diameter end of the connecting short section 11 is on the right side).

[0054] A tapered roller bearing 19 is installed on each of the left and right sides of the transmission spindle 13 (the bearing steel column is inclined towards both ends).

[0055] The assembled drive spindle 13 is inserted into the connecting short section 11 and connected to the spline drive rod 10 via a spline.

[0056] The outer balance cylinder 12 is passed through the transmission spindle 13 and connected to the connecting short section 11;

[0057] Connect the nozzle 14 to the drive spindle 13.

[0058] The working method of this downhole rotary jet cutting tool is as follows: the liquid enters the fixed impeller and the moving impeller through the filter screen, the impeller generates high-speed rotation, the rotation is transmitted to the reducer through the balance bar and the transmission bar, the reducer outputs the input high-speed, low-torque rotation as uniform speed, low speed, high torque rotation through the internal reduction device, the rotation is transmitted to the nozzle through each spindle, so that the nozzle rotates;

[0059] Liquid is ejected through nozzles inside the nozzle. The force of liquid injection is determined by adjusting the nozzle diameter according to different tasks, thereby achieving jet cutting and well washing operations.

[0060] During operation, steel balls and bearings play a role in reducing friction.

[0061] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A downhole rotary jet cutting tool characterized by: The upper joint (1) is connected with the lower female end of the outer cylinder (3), the outer cylinder (3) is provided with a filter screen (2) and an impeller assembly, the impeller assembly comprises a balance bar (4), a fixed impeller (5) and a moving impeller (6), the bottom end of the upper joint (1) is connected with the filter screen (2) through spline engagement, the bottom end of the filter screen (2) is connected with the impeller assembly through spline engagement, the lower end of the balance bar (4) penetrates through the fixed impeller (5) and enters the moving impeller (6) and is connected with the first tight top screw (16), the lower end of the moving impeller (6) is connected with a transmission rod (7), the outer wall surface of the thin shaft part of the transmission rod (7) is provided with a deep groove ball bearing (17), the outer diameter of the deep groove ball bearing (17) is provided with a transmission sleeve (8), the lower end of the transmission rod (7) is connected with a speed reducer (22) through spline engagement, the bottom of the speed reducer (22) is connected with an overflow disc (9), the bottom end of the speed reducer (22) extends to the inner hole of the overflow disc (9) and is connected with a spline transmission rod (10), the lower end of the spline transmission rod (10) is connected with a transmission mandrel (13) through spline engagement, the outer side surface of the upper part of the spline transmission rod (10) and the transmission mandrel (13) is provided with a connecting short section (11), the upper male end of the connecting short section (11) is connected with the lower female end of the outer cylinder (3), the lower male end of the connecting short section (11) is connected with the upper female end of a balance outer cylinder (12), the transmission mandrel (13) penetrates out of the balance outer cylinder (12) and is connected with a nozzle (14), and a tapered roller bearing (19) is arranged between the outer wall surface of the transmission mandrel (13) and the inner wall surface of the balance outer cylinder (12).

2. The downhole rotary jet cutting tool of claim 1, wherein: The bottom surface of the moving impeller (6) is provided with a groove, and the top surface of the transmission rod (7) is provided with a convex point, and the groove is matched with the convex point.

3. The downhole rotary jet cutting tool of claim 1, wherein: The overflow disc (9) is connected with the speed reducer (22) through the second tight top screw (18).

4. The downhole rotary jet cutting tool of claim 1, wherein: First O-rings (20) are arranged at the connection between the upper joint (1) and the outer cylinder (3).

5. The downhole rotary jet cutting tool of claim 1, wherein: Steel ball grooves are arranged on the matching surfaces between the fixed impeller (5) and the balance bar (4), and the steel ball grooves are filled with steel balls (15).

6. The downhole rotary jet cutting tool of claim 1, wherein: The outer wall surface of the speed reducer (22) is connected with the transmission sleeve (8) through the second tight top screw (18).

7. The downhole rotary jet cutting tool of claim 1, wherein: First O-rings (20) are arranged at the connection between the outer cylinder (3) and the connecting short section (11), and first O-rings (20) are arranged at the connection between the connecting short section (11) and the balance outer cylinder (12).

8. The downhole rotary jet cutting tool of claim 1, wherein: Second O-rings (21) are arranged at the connection between the transmission mandrel (13) and the nozzle (14).

9. A method of assembling a downhole rotary jet cutting tool according to any one of claims 1 to 8, characterised in that, The following steps are included: The impeller assembly is arranged on the left side of the outer cylinder (3), the balance bar (4) in the impeller assembly is on the left side, the fixed impeller (5) is in the middle, and the two are connected through spline engagement, and then the moving impeller (6) is assembled; The filter screen (2) and the upper joint (1) are sequentially arranged on the left side of the outer cylinder, and the upper joint (1), the filter screen (2) and the impeller assembly are connected through spline engagement; The deep groove ball bearing (17) is arranged in the thin shaft end of the transmission rod (7), and the transmission sleeve (8) is arranged at the outer diameter of the deep groove ball bearing; The transmission rod (7) is assembled from the right side of the outer cylinder (3), the stationary vane (5) and the balancing rod (4) are matched with a steel ball groove, the groove is filled with steel balls (15); The speed reducer (22) is assembled, the speed reducer (22) is meshed with the right side spline of the transmission rod (7); The flow disc (9) is assembled, the flow disc (9) is connected with the speed reducer (22) through the second top screw (18); The spline transmission rod (10) is assembled from the right side of the outer cylinder (3) and connected with the speed reducer (22); The connecting section (11) is assembled from the right side of the outer cylinder (3); The tapered roller bearings (19) are assembled on the left and right sides of the transmission mandrel (13); The assembled transmission mandrel (13) is assembled into the connecting section (11) and connected with the spline transmission rod (10) through spline; The balance outer cylinder (12) is connected with the connecting section (11) through the transmission mandrel (13); The nozzle (14) is connected with the transmission mandrel (13).

10. A method of operating the downhole rotary jet cutting tool of any one of claims 1-8, characterized by: The liquid enters the stationary vane and the moving vane through the filter screen, the vane rotates at high speed, the rotation is transmitted to the speed reducer through the balancing rod and the transmission rod, the speed reducer outputs uniform speed, low speed and high torque rotation through the internal speed reduction device, the rotation is transmitted to the nozzle through the mandrel, so that the nozzle rotates; The liquid is sprayed through the nozzle in the nozzle, according to different operation contents, the diameter of the nozzle is adjusted to determine the intensity of the liquid spray, so as to realize the spray cutting and well washing operation.

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