A high-efficiency well repair mill shoe suitable for horizontal wells and high-deviation wells

Abstract

The present application relates to a kind of drill and mill tool for drilling out oil and gas field wellbore metal blockage, especially a kind of anti-deviation grinding high-efficiency workover mill shoe suitable for horizontal well and high-deviation well.The anti-deviation grinding high-efficiency workover mill shoe mainly comprises a workover mill shoe joint, an anti-deviation grinding ball device, a workover mill shoe small cutter wing A, a honeycomb abrasive, a workover mill shoe eccentric cutter wing, a workover mill shoe small cutter wing B, a workover mill shoe base body and a workover mill shoe water eye.The workover mill shoe base body is circumferentially arranged with five rows of anti-deviation grinding ball devices on the outer side, and the front end surface of the workover mill shoe cutter wing is arranged with a single row of multi-layer honeycomb abrasives.The invention has high drilling efficiency, the bottom cutter wing is of eccentric structure, which avoids the occurrence of zero cutting speed point, the same layer of abrasives can form a complete cutting edge in a wave shape, and the tooth arrangement angle is optimized to improve the drilling efficiency.The anti-deviation grinding ball device plays a supporting role to prevent the workover mill shoe from damaging the inner wall of the casing during rotation.

Description

TECHNICAL FIELD

[0001] The present invention relates to a drilling and milling tool for drilling out metal plugs in wellbore of oil and gas fields, in particular to a high-efficiency well repair milling shoe for preventing eccentric wear and suitable for horizontal wells and high-deviation wells. BACKGROUND

[0002] When wellbore plugging occurs in oil and gas wells, a well repair milling shoe needs to be lowered to drill out metal plugs and realize large-diameter production of oil and gas wells. The well repair milling shoe is a core tool for drilling out wellbore plugs and determines the efficiency of construction, and is widely used in oil and gas fields. With the development of oil and gas exploration and development towards "low permeability, deep layer, sea area and unconventional" fields, complex structure wells characterized by high-deviation wells or horizontal wells have become advanced well type technologies for efficient development of oil and gas resources. Due to the increasing complexity of wellbore structure, the corresponding well repair technology is also extremely challenging, and higher requirements are put forward for the working performance of the well repair milling shoe. On the one hand, due to fracturing and acidizing construction processes, downhole tools of horizontal wells and high-deviation wells often bear a large fluid flow rate and sand erosion, so the wellbore metal plugs are usually made of wear-resistant metal materials such as nodular cast iron, resulting in a very low drilling efficiency of the current well repair milling shoe; on the other hand, when drilling out the metal plugs in the wellbore of horizontal wells or high-deviation wells, the current well repair milling shoe is prone to eccentric wear due to its own weight, which further damages the inner wall of the wellbore casing of horizontal wells or high-deviation wells. SUMMARY

[0003] The present invention aims to overcome the above-mentioned defects of the existing well repair milling shoe and proposes a high-efficiency well repair milling shoe for preventing eccentric wear and suitable for horizontal wells and high-deviation wells, which can replace the same products of the present stage of the invention, and the technical scheme adopted is as follows:

[0004] A high-efficiency well workover shoe with anti-eccentric wear, suitable for horizontal and highly deviated wells, mainly consists of a workover shoe connector, an anti-eccentric wear ball device, a workover shoe small blade A, honeycomb abrasive grains, an eccentric blade, a workover shoe small blade B, a workover shoe base, and a workover shoe water eye. The anti-eccentric wear ball device mainly consists of anti-eccentric wear balls, anti-eccentric wear fastening hexagonal plugs, and anti-eccentric wear internal hexagonal fastening screws. The honeycomb abrasive grain mainly consists of the abrasive grain side, the abrasive grain right cutting edge, the abrasive grain tip, the abrasive grain left cutting edge, and the abrasive grain chip breaking groove. The angle formed between the front end face of the honeycomb abrasive grain and the vertical plane of the bottom surface of the workover shoe blade is the tooth distribution angle. The workover shoe eccentric blade mainly consists of the front blade, the middle blade, and the rear blade. A high-efficiency workover shoe with anti-eccentric wear, suitable for horizontal and highly deviated wells, is installed at the bottom of the workover string. The bottom of the workover string and the workover shoe connector are fixedly connected by threads. The workover shoe connector and the workover shoe base are an integral structure. Five rows of anti-eccentric wear ball bearings are evenly arranged circumferentially on the outer side of the workover shoe base. The anti-eccentric wear ball bearings are fixedly connected to the workover shoe base by threads. The workover shoe small blade A, the workover shoe eccentric blade, and the workover shoe small blade B are fixed to the workover section by welding. At the bottom of the grinding shoe base, the front faces of the small blade A, eccentric blade, and small blade B of the well-repairing grinding shoe are arranged with a single row of multi-layer honeycomb abrasive grains. The honeycomb abrasive grains in the same layer can form a complete wavy cutting edge. Six water eyes are arranged at the bottom of the well-repairing grinding shoe base, including a large water eye in the center and five small water eyes in the circumference. The five small water eyes in the circumference are arranged on the front side of the small blade A, eccentric blade, and small blade B of the well-repairing grinding shoe.

[0005] The aforementioned high-efficiency workover shoe, suitable for horizontal and highly deviated wells, features five rows of countersunk threaded holes evenly arranged circumferentially on the outer side of the workover shoe base. An anti-wear-resistant hexagonal plug on the outside of the anti-wear-resistant ball bearing device is fixedly connected to the countersunk threaded holes on the outer side of the workover shoe base via threaded engagement. Inside the anti-wear-resistant hexagonal plug, anti-wear-resistant balls and anti-wear-resistant internal hexagonal fastening screws are arranged sequentially from top to bottom. A circular hole is located at the center of the top of the anti-wear-resistant hexagonal plug, with an outer diameter slightly smaller than the outer diameter of the anti-wear-resistant balls to prevent them from falling out. The anti-wear-resistant internal hexagonal fastening screw... A concave spherical surface is arranged at the center of the top of the nail. The concave spherical surface at the center of the top of the anti-wear hexagonal socket head cap screw mates with the anti-wear ball, allowing the anti-wear ball to roll inside the anti-wear ball device. The anti-wear hexagonal socket head cap screw and the bottom of the anti-wear hexagonal socket head cap screw are fixedly connected by threads. The top of the anti-wear hexagonal socket head cap screw is lower than the outer surface of the workover shoe base, while the spherical surface of the anti-wear ball is higher than the outer surface of the workover shoe base. By replacing the anti-wear ball with different sizes and adjusting the position of the anti-wear hexagonal socket head cap screw, the height of the anti-wear ball above the outer surface of the workover shoe base can be adjusted, making it suitable for casings with different inner diameters.

[0006] Specifically, the bottom of the well-repairing grinding shoe base is sequentially arranged with a small cutting blade A, an eccentric cutting blade, and a small cutting blade B. The bottom of the well-repairing grinding shoe base is fixedly connected to the small cutting blade A, the eccentric cutting blade, and the small cutting blade B by welding. The front end face of the small cutting blade A is arranged with a single row of multi-layered honeycomb abrasive grains, and the small cutting blade A is fixedly connected to the honeycomb abrasive grains by welding. A water eye is arranged in front of the honeycomb abrasive grains on the front end face of the small cutting blade A. The rear end face of the small cutting blade A is formed by welding together broken hard alloy abrasive grains. The eccentric cutting blade is arranged on one side of the bottom of the well-repairing grinding shoe base, while avoiding the repair... At the center of the bottom of the well-grinding shoe base, a water inlet is arranged. The eccentric blade of the well-grinding shoe mainly consists of the front blade, the middle blade, and the rear blade. The inner sides of the front, middle, and rear blades are fixedly connected by welding. A single row of multi-layered honeycomb abrasive grains is arranged on the front face of the front blade. The front blade and the honeycomb abrasive grains are fixedly connected by welding. A water inlet is arranged in front of the honeycomb abrasive grains on the front face of the front blade. The rear end face of the front-end blade is welded together from crushed cemented carbide abrasive grains. The front end face of the eccentric blade in the middle of the well-dredging shoe is arranged with a single row of multi-layered honeycomb abrasive grains. The middle blade of the eccentric blade in the well-dredging shoe is fixedly connected to the honeycomb abrasive grains by welding. A well-dredging shoe water eye is arranged in front of the honeycomb abrasive grains on the front end face of the middle blade of the eccentric blade in the well-dredging shoe. The rear end face of the middle blade of the eccentric blade in the well-dredging shoe is welded together from crushed cemented carbide abrasive grains. The front end face of the rear end blade of the eccentric blade in the well-dredging shoe is arranged with a single row of multi-layered honeycomb abrasive grains. The rear end blade of the eccentric blade in the well-dredging shoe is fixedly connected to the honeycomb abrasive grains by welding. A water eye is arranged in front of the honeycomb abrasive grains on the front end face of the rear end blade of the eccentric blade in the well-dredging shoe. The well-drilling shoe has water inlets. The rear end face of the eccentric blade of the well-drilling shoe is made of crushed cemented carbide abrasive grains welded together. The front end face of the small blade B of the well-drilling shoe is arranged with a single row of multi-layered honeycomb abrasive grains. The small blade B of the well-drilling shoe is fixedly connected to the honeycomb abrasive grains by welding. The well-drilling shoe water inlets are arranged in front of the honeycomb abrasive grains on the front end face of the small blade B of the well-drilling shoe. The rear end face of the small blade B of the well-drilling shoe is made of crushed cemented carbide abrasive grains welded together. The length of the teeth of the front blade of the eccentric blade of the well-drilling shoe is greater than the radius of the well-drilling shoe base. The length of the teeth of the small blade A, the middle blade of the eccentric blade of the well-drilling shoe, the rear blade of the eccentric blade of the well-drilling shoe, and the small blade B of the well-drilling shoe is less than the radius of the well-drilling shoe base.

[0007] Specifically, the front ends of the workover shoe blades A, B, and C, including the workover shoe eccentric blade and the workover shoe blade B, are arranged with a single row of multi-layered honeycomb abrasive grains. The honeycomb abrasive grains are hexagonal prisms with a front end area larger than the rear end area. The abrasive grain tips are arranged downwards. Under the action of drilling pressure, the abrasive grain tips are pressed into the surface of the metal blockage. The metal blockage is removed by the cutting action of the right and left cutting edges of the abrasive grains. The front end of the honeycomb abrasive grains is arranged with an annular chip-breaking groove, which enables the chips to curl and break. The honeycomb abrasive grains in the same layer are fixedly connected to each other by welding. The top and bottom surfaces of the honeycomb abrasive grains in the upper and lower layers are fixedly connected by welding.

[0008] In particular, the tooth angle of the honeycomb abrasive grains has been optimized. Taking into account both the working efficiency and safety of the well repair shoe, the tooth angle of the honeycomb abrasive grains is preferably a negative front angle of 10°. At this angle, the working efficiency of the well repair shoe is high, and the working process is relatively stable.

[0009] The present invention has the following advantages: a high-efficiency workover shoe suitable for horizontal wells and highly deviated wells, which has the advantages of high drilling efficiency, long service life, easy chip return and avoidance of casing wear. (1) High drilling efficiency. The bottom blade of the workover shoe is an eccentric structure to avoid the zero cutting speed point and prevent the material in the center of the wellbore metal blockage from being unable to be removed, thus affecting the drilling efficiency of the workover shoe. The front end face of the bottom blade of the workover shoe is overlaid with a single row of multi-layer honeycomb abrasive grains. The honeycomb abrasive grains in the same layer can form a complete wave-shaped cutting edge, which improves the drilling efficiency of the wellbore metal blockage. The tooth angle of the honeycomb abrasive grains is optimized and designed to be a negative front angle of 10°. At this time, the working efficiency of the workover shoe is high and the working process is relatively stable. (2) Long service life. The water inlet of the well workover shoe is located in front of the honeycomb abrasive grains on the front end face of the well workover shoe blade. This can effectively reduce the working temperature of the honeycomb abrasive grains, avoid high-temperature damage to the honeycomb abrasive grains, and extend the service life of the well workover shoe. (3) Easy chip return. The front end face of the honeycomb abrasive grains is arranged with an annular chip breaking groove. The chip breaking groove is conducive to the curling and breaking of chips, thereby effectively reducing the volume of chips and facilitating chip return. (4) Avoid uneven wear on the casing. The anti-uneven wear ball device arranged on the outside of the well workover shoe plays a supporting role, preventing uneven wear during the rotation of the well workover shoe and damaging the inner wall of the casing of the horizontal well or highly inclined well. By replacing the anti-uneven wear ball with different sizes and adjusting the position of the anti-uneven wear hexagonal fastening screw, the height of the anti-uneven wear ball above the outer surface of the well workover shoe base can be adjusted, thus making it suitable for casings with different inner diameters. Attached Figure Description

[0010] Figure 1 : A structural diagram of an anti-wear, high-efficiency well workover shoe suitable for horizontal and highly deviated wells.

[0011] Figure 2 A plan view of the bottom of a high-efficiency well workover shoe suitable for horizontal and highly deviated wells, designed to prevent uneven wear.

[0012] Figure 3 : A structural diagram of the bottom surface of a high-efficiency well workover shoe that is suitable for horizontal wells and highly deviated wells, designed to prevent uneven wear.

[0013] Figure 4 : Structural diagram of anti-wear ball bearing device.

[0014] Figure 5 : Diagram of honeycomb abrasive grain arrangement.

[0015] Figure 6 : Angle diagram of honeycomb abrasive cloth teeth.

[0016] Symbol explanation:

[0017] 1. Well workover shoe connector; 2. Anti-wear ball bearing device; 2.1 Anti-wear ball bearing; 2.2 Anti-wear fastening hexagonal plug; 2.3 Anti-wear internal hexagonal fastening screw; 3. Well workover shoe small blade A; 4. Honeycomb abrasive grain; 4.1 Abrasive grain side; 4.2 Abrasive grain right cutting edge; 4.3 Abrasive grain tip; 4.4 Abrasive grain left cutting edge; 4.5 Abrasive grain chip breaking groove; 5. Well workover shoe eccentric blade; 5.1 Well workover shoe eccentric blade front blade; 5.2 Well workover shoe eccentric blade middle blade; 5.3 Well workover shoe eccentric blade rear blade; 6. Well workover shoe small blade B; 7. Well workover shoe base; 8. Well workover shoe water eye; 9. Tooth angle. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and examples:

[0019] like Figures 1-5As shown, the present invention relates to a high-efficiency well workover shoe with anti-eccentric wear suitable for horizontal wells and highly deviated wells. It mainly consists of a well workover shoe connector 1, an anti-eccentric wear ball device 2, a well workover shoe small blade A3, honeycomb abrasive particles 4, a well workover shoe eccentric blade 5, a well workover shoe small blade B6, a well workover shoe base 7, and a well workover shoe water eye 8. The anti-eccentric wear ball device 2 mainly consists of anti-eccentric wear balls 2.1, anti-eccentric wear fastening hexagonal plugs 2.2, and anti-eccentric wear internal hexagonal fastening screws 2. The device consists of three parts: the honeycomb abrasive grain 4 mainly consists of the abrasive grain side 4.1, the abrasive grain right cutting edge 4.2, the abrasive grain tip 4.3, the abrasive grain left cutting edge 4.4, and the abrasive grain chip breaking groove 4.5. The angle formed between the front end face of the honeycomb abrasive grain 4 and the vertical plane of the bottom surface of the well repair shoe blade is the tooth angle 9. The well repair shoe eccentric blade 5 mainly consists of the front blade 5.1, the middle blade 5.2, and the rear blade 5.3 of the well repair shoe eccentric blade. A high-efficiency workover shoe with anti-eccentric wear, suitable for horizontal and highly deviated wells, is installed at the bottom of the workover string. The bottom of the workover string is fixedly connected to the workover shoe connector 1 by threads. The workover shoe connector 1 and the workover shoe base 7 are integral structures. Five rows of anti-eccentric wear ball bearing devices 2 are evenly arranged circumferentially on the outer side of the workover shoe base 7. The anti-eccentric wear ball bearing devices 2 are fixedly connected to the workover shoe base 7 by threads. The workover shoe small blade A3, the workover shoe eccentric blade 5, and the workover shoe small blade B6 are fixedly welded to the workover shoe. At the bottom of the shoe base 7, a single row of multi-layer honeycomb abrasive grains 4 are arranged on the front face of the well-repairing and grinding shoe small blade A3, the well-repairing and grinding shoe eccentric blade 5, and the well-repairing and grinding shoe small blade B6. The honeycomb abrasive grains 4 in the same layer can form a complete wavy cutting edge. Six well-repairing and grinding shoe water eyes 8 are arranged at the bottom of the well-repairing and grinding shoe base 7, including a large water eye in the center and five small water eyes in the circumference. The five small water eyes in the circumference are arranged on the front side of the well-repairing and grinding shoe small blade A3, the well-repairing and grinding shoe eccentric blade 5, and the well-repairing and grinding shoe small blade B6.

[0020] The aforementioned high-efficiency workover shoe, suitable for horizontal and highly deviated wells, features a workover shoe base 7 with five rows of countersunk threaded holes evenly arranged circumferentially on its outer side. The anti-wear ball bearing device 2 has an anti-wear fastening hexagonal plug 2.2 on its exterior, which is fixedly connected to the countersunk threaded holes on the outer side of the workover shoe base 7 via threaded engagement. Inside the anti-wear fastening hexagonal plug 2.2, anti-wear balls 2.1 and anti-wear internal hexagonal fastening screws 2.3 are arranged sequentially from top to bottom. A circular hole is located at the center of the top of the anti-wear fastening hexagonal plug 2.2, with the outer diameter slightly smaller than that of the anti-wear balls 2.1 to prevent them from falling out. The anti-wear internal hexagonal fastening screw 2.3 is located at the top. A concave spherical surface is arranged at the center of the part. The concave spherical surface at the top center of the anti-wear hexagonal head screw 2.3 mates with the anti-wear ball 2.1. The anti-wear ball 2.1 can roll inside the anti-wear ball device 2. The anti-wear hexagonal head screw 2.3 and the bottom of the anti-wear hexagonal head screw plug 2.2 are fixedly connected by threads. The top of the anti-wear hexagonal head screw plug 2.2 is lower than the outer surface of the workover shoe base 7, and the spherical surface of the anti-wear ball 2.1 is higher than the outer surface of the workover shoe base 7. By replacing the anti-wear ball 2.1 of different sizes and adjusting the position of the anti-wear hexagonal head screw 2.3, the height of the anti-wear ball 2.1 above the outer surface of the workover shoe base 7 can be adjusted, which is suitable for casings with different inner diameters.

[0021] The aforementioned high-efficiency well workover shoe, suitable for horizontal and highly deviated wells, features a base 7 with a bottom arrangement of a small workover shoe blade A3, an eccentric blade 5, and a small workover shoe blade B6. The base 7 is welded to the small workover shoe blades A3, 5, and B6. The front end of the small workover shoe blade A3 has a single row of multi-layered honeycomb abrasive particles 4, which are welded to it. A water eye 8 is positioned in front of the honeycomb abrasive particles 4 on the front end of the small workover shoe blade A3. The rear end of the small workover shoe blade A3 is constructed from crushed hard alloy abrasive particles. The eccentric blade... 5 is arranged on one side of the bottom of the well-repairing shoe base 7, while the eccentric blade 5 of the well-repairing shoe avoids the center of the bottom of the well-repairing shoe base 7. The well-repairing shoe water eye 8 is arranged at the center of the bottom of the well-repairing shoe base 7. The eccentric blade 5 of the well-repairing shoe is mainly composed of the front blade 5.1, the middle blade 5.2, and the rear blade 5.3 of the well-repairing shoe. The inner sides of the front blade 5.1, the middle blade 5.2, and the rear blade 5.3 of the well-repairing shoe are fixedly connected by welding. The front face of the front blade 5.1 of the well-repairing shoe is arranged with a single row of multi-layer honeycomb abrasive grains 4. The front blade 5.1 of the well-repairing shoe is connected to the honeycomb abrasive grains 4. The well-working shoe is fixedly connected by welding. The honeycomb abrasive grains 4 on the front face of the eccentric cutter wing 5.1 are arranged with water holes 8. The rear face of the front cutter wing 5.1 is made of crushed carbide abrasive grains welded together. The front face of the middle cutter wing 5.2 is arranged with a single row of multi-layered honeycomb abrasive grains 4. The middle cutter wing 5.2 and the honeycomb abrasive grains 4 are fixedly connected by welding. The water holes 8 are arranged in front of the honeycomb abrasive grains 4 on the front face of the middle cutter wing 5.2. The rear face of the middle cutter wing 5.2 is made of crushed carbide abrasive grains welded together. The front face of the rear cutter wing 5.3 is arranged with a single row of multi-layered honeycomb abrasive grains 4. The well-drilling shoe features a multi-layered honeycomb abrasive grain 4. The rear end blade 5.3 of the eccentric blade wing is welded to the honeycomb abrasive grain 4. A water eye 8 is positioned in front of the honeycomb abrasive grain 4 on the front face of the rear end blade 5.3. The rear end face of the rear end blade 5.3 is constructed from welded fragments of cemented carbide abrasive grains. A single row of multi-layered honeycomb abrasive grains 4 is arranged on the front face of the small blade B6. The small blade B6 is welded to the honeycomb abrasive grain 4. A water eye 8 is positioned in front of the honeycomb abrasive grain 4 on the front face of the small blade B6. The rear end face of the small blade B6 is constructed from welded fragments of cemented carbide abrasive grains. The front end blade 5.3 of the eccentric blade wing is also present.The length of the toothed blades of blade 1 is greater than the radius of the well-repairing shoe base 7. The lengths of the toothed blades of blades A3, 5.2 (middle part of the eccentric blade), 5.3 (rear part of the eccentric blade), and B6 are less than the radius of the well-repairing shoe base 7.

[0022] The aforementioned high-efficiency workover shoe, suitable for horizontal and highly deviated wells, features a single-row, multi-layered honeycomb abrasive grains 4 arranged on the front faces of the workover shoe's small blade A3, eccentric blade 5, and small blade B6. The honeycomb abrasive grains 4 are hexagonal prisms with a front-end area larger than the rear-end area, and the abrasive grain tips 4.3 are arranged downwards. Under drilling pressure, the abrasive grain tips 4.3 are pressed into the surface of metal blockages. The metal blockages are removed by the cutting action of the right cutting edge 4.2 and the left cutting edge 4.4 of the abrasive grains. The front face of the honeycomb abrasive grains 4 is equipped with an annular chip-breaking groove 4.5, which enables the curling and breaking of chips. The honeycomb abrasive grains 4 in the same layer are fixedly connected to each other by welding on their side surfaces 4.1, and the honeycomb abrasive grains in upper and lower layers are fixedly connected to each other by welding on their top and bottom surfaces.

[0023] The aforementioned anti-eccentric wear high-efficiency well workover shoe suitable for horizontal and highly deviated wells features a honeycomb abrasive grain 4 with an optimized tooth angle 9. Considering both the working efficiency and safety of the well workover shoe, the optimal tooth angle 9 of the honeycomb abrasive grain 4 is a negative front angle of 10°. At this angle, the well workover shoe has high working efficiency and a relatively stable working process.

[0024] The working principle of an anti-eccentric wear high-efficiency workover shoe suitable for horizontal and highly deviated wells is as follows: When there is metal blockage in the wellbore of a horizontal or highly deviated well, under the interaction of drilling pressure and rotation speed, the anti-eccentric wear high-efficiency workover shoe mainly relies on the cutting action of the honeycomb-shaped abrasive particles 4 welded to the bottom to remove the metal blockage in the wellbore. The anti-eccentric wear ball device 2 arranged on the outside of the anti-eccentric wear high-efficiency workover shoe plays a supporting role, preventing the workover shoe from causing eccentric wear during rotation and damaging the inner wall of the casing of the horizontal or highly deviated wellbore.

[0025] The working process of a high-efficiency well workover shoe that prevents uneven wear and is suitable for horizontal and highly deviated wells is as follows:

[0026] The first step is to install the anti-wear high-efficiency workover shoe at the bottom of the workover string via threads. The anti-wear high-efficiency workover shoe is lowered with the workover string to a position 0.5 meters above the metal blockage in the wellbore. At this time, the workover fluid circulation system is started. The workover fluid is injected from the wellhead through the central tube of the workover string and flows out from the water hole 8 of the anti-wear high-efficiency workover shoe. Finally, it is returned to the wellhead through the annular space between the workover string and the casing.

[0027] The second step is to start the workover power system. The workover string begins to drive the anti-eccentric wear high-efficiency workover shoe to rotate. At this time, the workover string continues to be lowered so that the abrasive tips 4.3 of the honeycomb abrasive particles 4 at the bottom of the anti-eccentric wear high-efficiency workover shoe begin to press into the surface of the metal blockage in the wellbore.

[0028] The third step involves continuing to lower the tubing string. Based on the reading on the index finger, the working pressure of the anti-wear high-efficiency workover shoe is increased. The abrasive tips 4.3 of the honeycomb-shaped abrasive grains 4 at the bottom of the anti-wear high-efficiency workover shoe continue to press into the surface of the metal blockage in the wellbore. At this point, under the combined action of drilling pressure and rotation speed, the honeycomb-shaped abrasive grains 4 begin to remove the metal blockage through the cutting action of their right cutting edge 4.2 and left cutting edge 4.4. The honeycomb-shaped abrasive grains 4 in the same layer can form a complete wavy cutting edge, improving the drilling efficiency of removing metal blockages from the wellbore. The anti-wear ball bearing device 2, arranged on the outside of the anti-wear high-efficiency workover shoe, provides support and prevents eccentric wear during the rotation of the workover shoe, thus preventing damage to the casing inner wall of horizontal or highly deviated wells. The eccentric blade 5 of the workover shoe can remove material from the center of the metal blockage in the wellbore, preventing the formation of a central fulcrum due to the inability to remove the material at the center. This central fulcrum hinders the downward drilling of the anti-eccentric wear high-efficiency workover shoe, ultimately affecting its drilling efficiency. Workover fluid is injected from the wellhead through the central tube of the workover string and flows out from the water inlet 8 of the workover shoe. On one hand, the water inlet 8 is positioned in front of the honeycomb abrasive particles 4 on the front faces of the small blades A3, eccentric blades 5, and small blades B6 of the workover shoe, effectively reducing the working temperature of the honeycomb abrasive particles 4. On the other hand, the workover fluid can return the cuttings generated by the honeycomb abrasive particles 4 to the wellhead through the annular space between the workover string and the casing. Simultaneously, an annular chip-breaking groove 4.5 is arranged on the front face of the honeycomb abrasive particles 4. The chip-breaking groove 4.5 facilitates the curling and breaking of chips, effectively reducing their volume and thus facilitating chip return.

[0029] In the fourth step, when the right cutting edge 4.2 and the left cutting edge 4.4 of the bottom layer of honeycomb abrasive grains 4 of the anti-wear high-efficiency well repair shoe are damaged, the blunting of the cutting edge leads to a rapid increase in the cutting force to remove the metal blockage in the well barrel. When the cutting force is greater than the weld connection strength between the honeycomb abrasive grains 4 and the substrate, the bottom layer of honeycomb abrasive grains 4 on the front end face of the small blade A3, the eccentric blade 5 and the small blade B6 of the well repair shoe will fall off. At this time, the honeycomb abrasive grains 4 of the upper layer begin to enter the cutting working state.

[0030] Fifth step: After the metal blockage in the wellbore has been removed, shut down the workover power system. At this point, the anti-wear high-efficiency workover shoe will stop rotating. Then shut down the workover fluid circulation system, raise the workover string to the wellhead, and remove the anti-wear high-efficiency workover shoe to complete the removal of the metal blockage in the wellbore.

[0031] The present invention has been described above by way of example, but the present invention is not limited to the specific embodiments described above. Any modifications or variations made based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A high-efficiency well workover shoe with anti-wear properties suitable for horizontal and highly deviated wells, characterized in that: A high-efficiency well workover shoe with anti-eccentric wear, suitable for horizontal and highly deviated wells, mainly consists of a workover shoe connector, an anti-eccentric wear ball device, a workover shoe small blade A, honeycomb abrasive grains, an eccentric blade, a workover shoe small blade B, a workover shoe base, and a workover shoe water eye. The anti-eccentric wear ball device mainly consists of anti-eccentric wear balls, anti-eccentric wear fastening hexagonal plugs, and anti-eccentric wear internal hexagonal fastening screws. The honeycomb abrasive grain mainly consists of the abrasive grain side, the abrasive grain right cutting edge, the abrasive grain tip, the abrasive grain left cutting edge, and the abrasive grain chip breaking groove. The angle formed between the front end face of the honeycomb abrasive grain and the vertical plane of the bottom surface of the workover shoe blade is the tooth distribution angle. The workover shoe eccentric blade mainly consists of the front blade, the middle blade, and the rear blade. A high-efficiency workover shoe with anti-eccentric wear, suitable for horizontal and highly deviated wells, is installed at the bottom of the workover string. The bottom of the workover string and the workover shoe connector are fixedly connected by threads. The workover shoe connector and the workover shoe base are an integral structure. Five rows of anti-eccentric wear ball bearings are evenly arranged circumferentially on the outer side of the workover shoe base. The anti-eccentric wear ball bearings are fixedly connected to the workover shoe base by threads. The workover shoe small blade A, the workover shoe eccentric blade, and the workover shoe small blade B are fixed to the workover section by welding. At the bottom of the grinding shoe base, the front faces of the small blade A, the eccentric blade, and the small blade B of the well repair grinding shoe are arranged with a single row of multi-layer honeycomb abrasive grains. The honeycomb abrasive grains in the same layer can form a complete wavy cutting edge. Six water eyes of the well repair grinding shoe are arranged at the bottom of the well repair grinding shoe base, including a large water eye in the center and five small water eyes in the circumference. The five small water eyes in the circumference are arranged on the front side of the small blade A, the eccentric blade, and the small blade B of the well repair grinding shoe. The length of the teeth on the front edge of the eccentric blade of the well repair shoe is greater than the radius of the well repair shoe base. The length of the teeth on the small blade A, the middle blade of the eccentric blade, the rear blade of the eccentric blade, and the small blade B of the well repair shoe is less than the radius of the well repair shoe base. The front faces of the well workover shoe's small blade A, eccentric blade, and small blade B are arranged with a single row of multi-layered honeycomb abrasive grains. The honeycomb abrasive grains are hexagonal prism structures with a front-end area larger than the rear-end area. The abrasive grain tips are arranged downwards. Under the action of drilling pressure, the abrasive grain tips are pressed into the surface of the metal blockage. The metal blockage is removed by the cutting action of the right and left cutting edges of the abrasive grains. The front face of the honeycomb abrasive grains is arranged with an annular chip-breaking groove, which enables the chips to curl and break. The honeycomb abrasive grains in the same layer are fixedly connected to each other by welding. The top and bottom surfaces of the honeycomb abrasive grains in the upper and lower layers are fixedly connected by welding.

2. The anti-wear, high-efficiency workover shoe suitable for horizontal and highly deviated wells according to claim 1, characterized in that: The bottom of the well-dredging grinding shoe base is sequentially arranged with three small cutting blades: A, eccentric cutting blade, and B. The bottom of the well-dredging grinding shoe base is fixedly connected to these three blades by welding. The front face of blade A features a single row of multi-layered honeycomb abrasive grains, which are fixedly connected to the blades by welding. A water inlet is positioned in front of the honeycomb abrasive grains on the front face of blade A. The rear face of blade A is constructed from crushed hard alloy abrasive grains welded together. The eccentric cutting blade is positioned on the well-dredging grinding shoe base. On one side of the bottom of the well-working shoe, the eccentric blades of the well-working shoe avoid the center of the bottom of the well-working shoe base. A water inlet for the well-working shoe is located at the center of the bottom of the well-working shoe base. The eccentric blades of the well-working shoe mainly consist of a front blade, a middle blade, and a rear blade. The inner sides of the front blade, the middle blade, and the rear blade are fixedly connected by welding. A single row of multi-layered honeycomb abrasive grains is arranged on the front face of the front blade. The front blade and the honeycomb abrasive grains are fixedly connected by welding. The well-working grinding shoe features a water inlet positioned in front of the honeycomb-shaped abrasive grains on the front face of the eccentric cutting edge. The rear face of the front cutting edge is constructed from welded fragments of cemented carbide abrasive grains. A single row of multi-layered honeycomb-shaped abrasive grains is arranged on the front face of the middle cutting edge. The middle cutting edge and the honeycomb-shaped abrasive grains are fixedly connected by welding. Water inlets are positioned in front of the honeycomb-shaped abrasive grains on the front face of the middle cutting edge. The rear face of the middle cutting edge is constructed from welded fragments of cemented carbide abrasive grains. A single row of multi-layered honeycomb-shaped abrasive grains is arranged on the front face of the rear cutting edge. The well-dredging shoe features a multi-layered honeycomb abrasive grain structure. The rear end of the eccentric blade of the well-dredging shoe is welded to the honeycomb abrasive grain. A water eye is positioned in front of the honeycomb abrasive grain on the front face of the rear end of the eccentric blade. The rear end face of the eccentric blade is constructed from welded fragments of cemented carbide abrasive grain. A single row of multi-layered honeycomb abrasive grains is arranged on the front face of the small blade B. The small blade B is welded to the honeycomb abrasive grain. A water eye is positioned in front of the honeycomb abrasive grain on the front face of the small blade B. The rear end face of the small blade B is constructed from welded fragments of cemented carbide abrasive grain.

3. The anti-wear, high-efficiency workover shoe suitable for horizontal and highly deviated wells according to claim 1, characterized in that: Five rows of countersunk threaded holes are evenly arranged circumferentially on the outer side of the workover shoe base. The anti-wear ball bearing device's anti-wear fastening hexagonal plug is fixedly connected to the countersunk threaded holes on the outer side of the workover shoe base via threaded engagement. Inside the anti-wear fastening hexagonal plug, anti-wear balls and anti-wear internal hexagonal fastening screws are arranged sequentially from top to bottom. A circular hole is located at the center of the top of the anti-wear fastening hexagonal plug, with an outer diameter slightly smaller than the outer diameter of the anti-wear balls to prevent them from falling out. A concave spherical surface is located at the center of the top of the anti-wear internal hexagonal fastening screw to prevent wear. The concave spherical surface at the center of the top of the hexagon socket head cap screw mates with the anti-wear ball bearing, allowing the anti-wear ball bearing to roll inside the anti-wear ball bearing device. The anti-wear socket head cap screw and the bottom of the anti-wear socket head cap screw plug are fixedly connected by threads. The top of the anti-wear socket head cap screw plug is lower than the outer surface of the workover shoe base, while the spherical surface of the anti-wear ball bearing is higher than the outer surface of the workover shoe base. By replacing the anti-wear ball bearings of different sizes and adjusting the position of the anti-wear socket head cap screw, the height of the anti-wear ball bearing above the outer surface of the workover shoe base can be adjusted, making it suitable for casings with different inner diameters.

4. The anti-wear, high-efficiency well workover shoe suitable for horizontal and highly deviated wells according to claim 1, characterized in that: The tooth angle of the honeycomb abrasive grains was optimized. Taking into account both the working efficiency and safety of the well repair shoe, the tooth angle of the honeycomb abrasive grains is a negative front angle of 10°. At this angle, the working efficiency of the well repair shoe is high, and the working process is relatively stable.

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