Method for protecting top drive and top drive protector combination

Abstract

The invention discloses a method for protecting a top drive and a top drive protector combination, and belongs to the technical field of well drilling equipment, the top drive protector combination comprises an upper flexible short circuit, a top drive protector and a lower flexible short circuit from top to bottom, three-level damping can be achieved, the lower end is connected with two drill rods to form a replacement column as a whole, and the replacement column is connected with the top drive protector. The top drive protector is of a structure with the large middle and the two small ends, the top drive protector is of a structure with the large middle and the two small ends, the overall strength requirement can be met, a large water hole can be obtained, and the top drive protector can be used for protecting the top drive and equipment on the upper portion of the top drive and preventing vibration energy of a drilling tool on the lower portion of the top drive from being transmitted upwards. The drilling efficiency and the drilling safety are effectively improved, two damping elements including the disc spring and the silicone oil are arranged in the top drive protector, the damping effect can be achieved when the top drive protector is in the pulled state and the pressed state so as to relieve axial run-out of a drill column, and the effect of protecting a top drive is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of drilling equipment, and in particular relates to a method for protecting a top drive and a top drive protector combination. Background Art

[0002] During the drilling process, the drill bit directly contacts the bottom of the well to break the rock and complete the footage. Due to the hardness or uneven hardness of the formation, interlayers, or the mismatch between the suitable drilling pressure of the drill bit and the actual drilling pressure, as well as the working principle of the drill bit, unfavorable situations such as drill bit jumping, drill string vibration and even well platform resonance may occur. Accidents such as drill tool breakage, wellhead equipment damage, and parts falling often occur, especially when drilling shallow wells, the drill bit is very close to the well platform, which is particularly obvious, not only wasting precious drilling time but also bringing economic losses and safety hazards.

[0003] At present, the commonly used drill string shock absorber is connected near the upper part of the drill bit at the bottom of the well. It works under pressure as the drill bit goes down to the bottom of the well. The spring shock-absorbing element in the drill string shock absorber absorbs vibration energy and ensures that the drill bit is always close to the bottom of the well for drilling, which serves the purpose of alleviating the vibration of the drill string and protecting the drill bit. The lower drill pipe of the top drive above the well platform is basically in a tensile state, which is exactly opposite to the force direction of the drill string at the bottom of the well. The actual situation is that the shock absorber on the upper part of the drill bit cannot completely eliminate the vibration generated by the drill bit. The vibration energy that is not eliminated continues to be transmitted upward to the top drive, derrick and other upper equipment, which may cause greater damage. Especially when drilling shallow wells, the drill bit is very close to the wellhead, and the vibration transmission speed is faster and more direct. When drilling the first column, there is not even a place to connect the drill string shock absorber, which is more destructive. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for protecting a top drive and a top drive protector combination, the purpose of which is to alleviate the upward transmission of vibration energy of the lower drilling tool and facilitate installation at the wellhead, thereby achieving the effect of protecting the top drive and upper equipment and facilitating the installation of the drill string at the wellhead.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme: a method for protecting a top drive, using a top drive protector assembly formed by an upper flexible short-circuit, a top drive protector and a lower flexible short-circuit, and installing two drill pipes at the lower end thereof, the whole is used as a replacement column, and is always immediately below the top drive during the drilling process, and the specific steps are as follows: S1, assembling the top drive protector assembly and the drill pipe; from top to bottom, the upper flexible short-circuit, the top drive protector and the lower flexible short-circuit are sequentially connected to form the top drive protector assembly, and then two drill pipes are connected to the lower end, so that the top drive protector assembly and the two drill pipes are integrally formed into a replacement column, the length of which is consistent with the length of the drill pipe column, and is erected on the well platform together with the pre-assembled drill pipe column; S2, connect the replacement column and start drilling; connect the drill pipe at the bottom of the replacement column with the conventional column, the conventional column is composed of a drill bit, a tool, a drill collar and a drill pipe, and lower it into the wellbore in advance until the drill bit is close to the bottom of the well, the interface between the drill pipe at the bottom of the replacement column and the conventional column is at the well platform plane, connect the upper flexible short-circuit at the top of the replacement column with the top drive, the interface between the upper flexible short-circuit at the top of the replacement column and the top drive is at the highest position at the upper end of the derrick, take the two interface positions as the origin position, start the pump circulation, start the top drive rotation, slowly lower it until the drill bit touches the bottom of the well, and start drilling; S3, pull out the drill and remove the replacement column; when the drill reaches the point where the lower end of the top drive protector of the replacement column is close to the rotary blowout preventer installed on the wellhead, stop lowering the drill string, rotate and lift it up until the lower end of the replacement column is on the well platform plane, return the replacement column to the original position, stop the pump, stop the top drive from rotating, unscrew the upper and lower end threads of the replacement column in turn, remove the replacement column, and stand it upright on the well platform; S4, replace the column and drill; connect a drill pipe column, start the pump cycle, rotate and lower it until the drill bit is close to the bottom of the well. At this time, the upper end of the newly connected drill pipe column reaches the well platform plane, stop the pump, stop the top drive from rotating, unscrew the upper end of the column, and lift the top drive to the origin position; S5, replace the column and continue drilling; re-install the replacement column, start the pump circulation, start the top drive rotation, slowly lower it until the drill bit touches the bottom of the well, and start drilling; S6, repeat S3 to S5 until the target well depth is reached; S7. Start drilling.

[0006] According to the above method, a top drive protector combination of the present invention is constructed, including an upper flexible short-circuit, a top drive protector and a lower flexible short-circuit which are sequentially installed from top to bottom. The upper flexible short-circuit and the lower flexible short-circuit are both hollow flexible structures that are thin in the middle and thick at both ends. A lifting outer cone is provided on the upper part of the upper flexible short-circuit. The top drive protector is a structure that is large in the middle and small at both ends. The top drive protector includes a shaft component and a cylinder component. The shaft parts and the cylinder parts are slidably connected. The shaft parts include a spindle and a piston. The spindle is respectively connected to the piston and the upper flexible short-circuit. The spindle is divided into a large diameter section, a middle diameter section and a small diameter section. The large diameter section and the middle diameter section are transitioned by a large fillet. A shaft shoulder is provided between the small diameter section and the middle diameter section. The disc spring is sleeved on the small diameter section. The cylinder component includes a cylinder body and a transmission outer cylinder. One end of the cylinder body is connected to the transmission outer cylinder, and the other end is connected to the lower flexible short-circuit. A lower oil filling hole is opened on the side wall of the cylinder body.

[0007] The transmission outer cylinder is provided with an upper oil filling port, a middle oil filling port, an arc oil storage groove, two groups of sealing ring grooves, a first bearing groove and a second bearing groove. The first bearing groove and the second bearing groove are arranged at intervals, and the two groups of sealing ring grooves are respectively arranged on both sides of the second bearing groove. The arc oil storage groove is arranged on the second bearing groove, the upper oil filling port is connected with the arc oil storage groove, the middle oil filling port is arranged at the lower end of the first bearing groove, and the middle oil filling port is connected with the cylinder body.

[0008] Adjusting washers are arranged at both ends of the disc spring, and oil grooves are arranged on the end faces and outer walls of the adjusting washers.

[0009] The middle diameter section of the spindle is provided with an anti-drop annular groove, the anti-drop half ring is sleeved on the anti-drop annular groove, the anti-drop half ring is provided with an anti-drop outer conical surface, the transmission outer cylinder is provided with an anti-drop inner conical surface, the anti-drop outer conical surface matches the anti-drop inner conical surface and has the same taper.

[0010] A limiting outer conical surface is also provided on the middle diameter section of the spindle, and a limiting inner conical surface is provided on the transmission outer cylinder. The limiting outer conical surface and the limiting inner conical surface cooperate to form a pressure limiting position.

[0011] The middle diameter section of the core shaft is also provided with a tension ring groove, the tension ring is sleeved on the tension ring groove and the clamping ring is sleeved on the tension ring to clamp the tension ring, a sliding sleeve is also sleeved on the tension ring and the tension ring and the sliding sleeve are slidably connected, an arc-shaped oil groove is provided on the end face of the sliding sleeve, and a straight oil groove is provided on the outer wall.

[0012] An outer hexagonal ring is sleeved on the piston, a locking nail hole is provided on the outer hexagonal ring, and an anti-retraction screw cooperates with the locking nail hole to relatively fix the piston and the spindle.

[0013] The beneficial effects of the invention are as follows: compared with the prior art, the invention adopts a top drive protector combination that can reduce shock both under tension and under compression, and the lower end is connected to two drill pipes to form an integral replacement column, and the column drilling is carried out by exchanging and connecting the top drive protector combination replacement column and the ordinary drill pipe column, ensuring that it is always closely connected to the bottom of the top drive during the drilling process, so that the top drive and upper equipment are protected by shock absorption; at the same time, the shortest time for connecting the drill column and the longest drilling depth after each connection are completed are achieved. During the exchange and connection process, the pump must be stopped when disassembling and installing the drill pipe column and the upper and lower end threads of the replacement column, and the pump can be turned on to circulate and rotate the drill column, which is equivalent to immediately reaming the eye after drilling, thereby improving the wellbore quality, ensuring underground safety, and preventing accidents caused by drill sticking due to too long column connection time. The top drive protector is designed as a structure that is large in the middle and small at both ends. It not only meets the overall strength requirements, but also can obtain a larger water hole, effectively improving the drilling efficiency and drilling safety. The method for protecting the top drive and the top drive protector combination of the present invention are not only suitable for air drilling with an air hammer, but also suitable for mud drilling with a conventional roller drill bit or a PDC drill bit. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 It is a schematic diagram of the combined structure of the top drive protector of the present invention; Figure 2 It is a schematic diagram of the structure of the top drive protector of the present invention; Figure 3 It is a schematic diagram of the mandrel structure of the present invention; Figure 4It is a schematic diagram of the structure of the transmission outer cylinder of the present invention; Figure 5 It is a schematic diagram of the cylinder structure of the present invention; Figure 6 It is a schematic diagram of the piston structure of the present invention; Figure 7 It is a cross-sectional view of the anti-drop half ring of the present invention; Figure 8 It is a cross-sectional view of an outer hexagonal ring of the present invention; Fig. 9 is a cross-sectional view of the sliding sleeve of the present invention; In the figure: 1. Upper flexible short-circuit; 11. Lifting outer cone; 2. Top drive protector; 21. Mandrel; 2101. Disc spring; 2102. Limit outer cone surface; 2103. Anti-drop annular groove; 2104. Anti-drop half ring; 2105. Anti-drop outer cone surface; 2106. Adjusting washer; 2107. Tension ring groove; 2108. Tension ring; 2109. Snap ring; 2110. Sliding sleeve; 2111. Arc oil groove; 2112. Straight oil groove; 22. Piston ; 2201, outer hexagonal ring; 2202, locking pin hole; 2203, anti-retraction screw; 23, cylinder body; 2301, lower oil filling hole; 24, transmission outer cylinder; 2401, upper oil filling hole; 2402, middle oil filling hole; 2403, arc oil storage tank; 2404, sealing ring groove; 2405, first bearing groove; 2406, second bearing groove; 2407, dust ring groove; 2408, limiting inner cone surface; 2409, anti-drop inner cone surface; 3, lower flexible short circuit. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0016] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined or replaced with each other according to actual conditions, and the same or similar concepts or processes may not be described in detail in some embodiments. Example

[0017] The present invention provides a method for protecting a top drive, which adopts a top drive protector assembly formed by connecting an upper flexible short-circuit 1, a top drive protector 2 and a lower flexible short-circuit 3, and two drill pipes are installed at the lower end thereof. The whole assembly is used as a replacement column and is always closely connected to the bottom of the top drive during the drilling process. The specific steps are as follows: S1, assembling the top drive protector assembly and the drill pipe; from top to bottom, the upper flexible short-circuit 1, the top drive protector 2 and the lower flexible short-circuit 3 are sequentially connected to form the top drive protector assembly, and then two drill pipes are connected to the lower end, so that the top drive protector assembly and the two drill pipes are integrally formed into a replacement column, the length of which is consistent with the length of the drill pipe column, and is erected on the well platform together with the pre-assembled drill pipe column; S2, connect the replacement column and start drilling; connect the drill pipe at the bottom of the replacement column with the conventional column, the conventional column is composed of a drill bit, a tool, a drill collar and a drill pipe, and lower it into the wellbore in advance until the drill bit is close to the bottom of the well, the interface between the drill pipe at the bottom of the replacement column and the conventional column is at the well platform plane, connect the upper flexible short-circuit 1 at the top of the replacement column with the top drive, the interface between the upper flexible short-circuit 1 at the top of the replacement column and the top drive is at the highest position at the upper end of the derrick, take the two interface positions as the origin position, start the pump circulation, start the top drive rotation, slowly lower it until the drill bit touches the bottom of the well, and start drilling; S3, pull out the drill and remove the replacement column; when the lower end of the top drive protector 2 of the replacement column is close to the rotary blowout preventer installed on the wellhead, stop lowering the drill string, rotate and lift it until the lower end of the replacement column is on the well platform plane, the replacement column returns to the original position, stops the pump, stops the top drive from rotating, unscrews the upper and lower end threads of the replacement column in turn, removes the replacement column, and stands it upright on the well platform; S4, replace the column and drill; connect a drill pipe column, start the pump cycle, rotate and lower it until the drill bit is close to the bottom of the well. At this time, the upper end of the newly connected drill pipe column reaches the well platform plane, stop the pump, stop the top drive from rotating, unscrew the upper end of the column, and lift the top drive to the origin position; S5, replace the column and continue drilling; re-install the replacement column, start the pump circulation, start the top drive rotation, slowly lower it until the drill bit touches the bottom of the well, and start drilling; S6, repeat S3 to S5 until the target well depth is reached; S7. Start drilling.

[0018] According to the above method, a top drive protector assembly of the present invention is formed, such as Figures 1 to 9As shown, it includes an upper flexible short-circuit 1, a top drive protector 2 and a lower flexible short-circuit 3 which are connected in sequence from top to bottom. The upper flexible short-circuit 1 and the lower flexible short-circuit 3 are both hollow flexible structures with a thin middle and thick ends. A lifting outer cone 11 is provided on the upper part of the upper flexible short-circuit 1. The top drive protector 2 is a structure with a large middle and small ends. The top drive protector 2 includes a shaft component and a cylinder component. The shaft parts and the cylinder parts are slidably connected. The shaft parts include a spindle 21 and a piston 22. The spindle 21 is respectively connected to the piston 22 and the upper flexible short-circuit 1. The spindle 21 is divided into a large diameter section, a middle diameter section and a small diameter section. The large diameter section and the middle diameter section are transitioned by a large fillet. A shoulder is provided between the small diameter section and the middle diameter section. The disc spring 2101 is sleeved on the small diameter section. The cylinder component includes a cylinder body 23 and a transmission outer cylinder 24. One end of the cylinder body 23 is connected to the transmission outer cylinder 24, and the other end is connected to the lower flexible short-circuit 3. A lower oil filling hole 2301 is provided on the side wall of the cylinder body 23.

[0019] The top drive protection combination formed by the top drive protector 2, the upper flexible short-circuit 1 and the lower flexible short-circuit 3 is connected with two drill pipes as replacement columns. The upper flexible short-circuit 1 is provided with a lifting outer cone 11 to facilitate the top drive to lift the replacement column. The lower flexible short-circuit 3 is connected to the drill pipe. Since the upper flexible short-circuit 1 and the lower flexible short-circuit 3 are both hollow flexible structures with thin middle and thick ends, the top drive protector 2 is provided with a disc spring 2101 and auxiliary silicone oil as shock-absorbing elements, and has a working stroke up and down, and has a bidirectional shock-absorbing effect. The top drive protector combination formed by the three can achieve three-level shock absorption, effectively buffer the bounce transmitted from the lower drill pipe, reduce or eliminate the serious harm of drilling jump to the top drive equipment, and extend the top drive The service life of the equipment is prolonged, and the central axis 21 of the top drive protector 2 is divided into three sections with different diameters, and the disc spring 2101 is sleeved on the small diameter section, which effectively increases the space for the disc spring 2101 and the auxiliary silicone oil, and further increases the shock absorption effect of the top drive protector 2; at the same time, in the process of connecting and replacing columns, except for the pump must be stopped when disassembling and installing the upper end buckle of the drill pipe column, the pump can be turned on to circulate and rotate the drill column, and because the length of the top drive protection device is consistent with the length of the ordinary drill pipe column, when the top drive protection device is connected, it can always be at the top of the drill column, that is, the position close to the top drive, which consumes less time, ensures underground safety, and prevents accidents such as drill sticking caused by too long column connection time.

[0020] Specifically, the transmission outer cylinder 24 is provided with an upper oil filling port 2401, a middle oil filling port 2402, an arc oil storage groove 2403, two groups of sealing ring grooves 2404, a first bearing groove 2405 and a second bearing groove 2406. The first bearing groove 2405 and the second bearing groove 2406 are spaced apart, and the two groups of sealing ring grooves 2404 are respectively arranged on both sides of the second bearing groove 2406. The arc oil storage groove 2403 is arranged on the second bearing groove 2406. The upper oil filling port 2401 is connected with the arc oil storage groove 2403, and the middle oil filling port 2402 is arranged at the left end of the first bearing groove 2405. The middle oil filling port 2402 is connected with the cylinder body 23. The arc oil storage groove 2403 stores grease for lubrication. The first bearing groove 2405 and the central shaft 21 are tightly matched to prevent the silicone oil flowing out of the middle oil filling port 2402 from flowing toward the first bearing groove 2405. The sealing ring groove 2404 arranged at the upper end of the first bearing groove 2405 further prevents the leakage of silicone oil.

[0021] Specifically, the disc spring 2101 has adjustment washers 2106 at both ends, and the end surface and outer wall of the adjustment washers 2106 are provided with oil grooves. The adjustment washers 2106 are provided to prevent the disc spring 2101 from directly contacting the piston 22 and the transmission outer cylinder 24, thereby reducing wear.

[0022] Specifically, in order to prevent the main shaft 21 from detaching from the transmission outer cylinder 24 during the relative movement among the main shaft 21, the transmission outer cylinder 24 and the cylinder body 23, the middle diameter section of the main shaft 21 is provided with an anti-drop annular groove 2103, and an anti-drop half ring 2104 is sleeved on the anti-drop annular groove 2103. An anti-drop outer conical surface 2105 is provided on the anti-drop half ring 2104, and an anti-drop inner conical surface 2409 is provided on the transmission outer cylinder 24. The anti-drop outer conical surface 2105 cooperates with the anti-drop inner conical surface 2409 and has the same taper.

[0023] Specifically, a limiting outer cone surface 2102 is provided on the middle diameter section 21 of the mandrel, and a limiting inner cone surface 2408 is provided on the transmission outer cylinder 24. The limiting outer cone surface 2102 and the limiting inner cone surface 2408 cooperate to form a pressure limiting position. The pressure limiting position effectively ensures that the silicone oil entering the high-pressure cylinder hole 2301 is within the allowable range, thereby ensuring the normal operation of the top drive protector 2.

[0024] Specifically, the middle diameter section of the mandrel 21 is further provided with a tension ring groove 2107, a tension ring 2108 is sleeved on the tension ring groove 2107, and a clamping ring 2109 is sleeved on the tension ring 2108 to clamp the tension ring 2108, a sliding sleeve 2110 is further sleeved on the tension ring 2108, and the tension ring 2108 is slidably connected with the sliding sleeve 2110, and an arc-shaped oil groove 2111 is provided on the end surface of the sliding sleeve 2110, and a straight oil groove 2112 is provided on the outer wall. The addition of the tension ring 2107 can significantly improve the rigidity of the mandrel 21, reduce the deformation and displacement of the mandrel 21 during the force process, and thus improve the stability and safety of the mandrel 21 during operation.

[0025] Specifically, the piston 22 is sleeved with an outer hexagonal ring 2201 , and the outer hexagonal ring 2201 is provided with a locking pin hole 2202 . The anti-retraction screw 2203 cooperates with the locking pin hole 2202 to relatively fix the piston 22 and the spindle 21 .

[0026] In addition to the above-mentioned preferred embodiments, the present invention also has other implementation modes. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection requested by the present invention.

Claims

1. A method for protecting a top drive, characterized in that: A top drive protector assembly formed by connecting an upper flexible short-circuit (1), a top drive protector (2) and a lower flexible short-circuit (3) is used, and two drill pipes are installed at the lower end of the assembly. The assembly is used as a replacement column and is always closely connected to the bottom of the top drive during drilling. The specific steps are as follows: S1, assembling the top drive protector assembly and the drill pipe; sequentially connecting the upper flexible short-circuit (1), the top drive protector (2) and the lower flexible short-circuit (3) from top to bottom to form the top drive protector assembly, and then connecting two drill pipes to the lower end, so that the top drive protector assembly and the two drill pipes as a whole become a replacement column, the length of the replacement column is consistent with the length of the drill pipe column, and is erected on the well platform together with the pre-connected drill pipe column; S2, connect the replacement column and start drilling; connect the drill pipe at the bottom of the replacement column with the conventional column, the conventional column is composed of a drill bit, a tool, a drill collar and a drill pipe, and lower it into the wellbore in advance until the drill bit is close to the bottom of the well, the interface between the drill pipe at the bottom of the replacement column and the conventional column is at the well platform plane, connect the upper flexible short-circuit (1) at the top of the replacement column with the top drive, the interface between the upper flexible short-circuit (1) at the top of the replacement column and the top drive is at the highest position at the top of the derrick, take the two interface positions as the origin position, start the pump circulation, start the top drive rotation, slowly lower it until the drill bit touches the bottom of the well, and start drilling; S3, pull out the drill string and remove the replacement column; when the drill string is drilled to the point where the lower end of the top drive protector (2) of the replacement column is close to the rotary blowout preventer installed on the wellhead, stop lowering the drill string, rotate and lift it up until the lower end of the replacement column is on the well platform plane, return the replacement column to the original position, stop the pump, stop the top drive from rotating, unscrew the upper and lower end threads of the replacement column in turn, remove the replacement column, and erect it on the well platform; S4, replace the column and drill; connect a drill pipe column to the top drive, start the pump cycle, rotate and lower it until the drill bit is close to the bottom of the well. At this time, the upper end of the newly connected drill pipe column reaches the well platform plane, stop the pump, stop the top drive from rotating, unscrew the upper end of the column, and lift the top drive to the origin position; S5, replace the column and continue drilling; re-install the replacement column, start the pump circulation, start the top drive rotation, slowly lower it until the drill bit touches the bottom of the well, and start drilling; S6, repeat S3 to S5 until the target well depth is reached; S7. Start drilling.

2. A top drive protector assembly according to the top drive protection method of claim 1, comprising an upper flexible short-circuit (1), a top drive protector (2) and a lower flexible short-circuit (3) connected in sequence from top to bottom, characterized in that: The upper flexible short-circuit (1) and the lower flexible short-circuit (3) are both hollow flexible structures that are thin in the middle and thick at both ends. The upper flexible short-circuit (1) is provided with a lifting outer cone (11) at the top. The top drive protector (2) is a structure that is large in the middle and small at both ends. The top drive protector (2) includes a shaft component and a cylinder component. The shaft parts and the cylinder parts are slidably connected. The shaft parts include a spindle (21) and a piston (22). The spindle (21) is connected to the piston (22) and the upper flexible short-circuit (1). The short-circuit (1) comprises a spindle (21) which is divided into a large diameter section, a middle diameter section and a small diameter section. The large diameter section and the middle diameter section are transitioned by a large fillet. A shaft shoulder is provided between the small diameter section and the middle diameter section. The disc spring (2101) is sleeved on the small diameter section. The cylinder assembly comprises a cylinder body (23) and a transmission outer cylinder (24). One end of the cylinder body (23) is connected to the transmission outer cylinder (24), and the other end is connected to the lower flexible short-circuit (3). The side wall of the cylinder body (23) is provided with a lower oil filling hole (2301).

3. The top drive protector assembly according to claim 2, characterized in that: The transmission outer cylinder (24) is provided with an upper oil filling port (2401), a middle oil filling port (2402), an arc oil storage groove (2403), two groups of sealing ring grooves (2404), a first bearing groove (2405) and a second bearing groove (2406); the first bearing groove (2405) and the second bearing groove (2406) are arranged at intervals; the two groups of sealing ring grooves (2404) are respectively arranged on both sides of the second bearing groove (2406); the arc oil storage groove (2403) is arranged on the second bearing groove (2406); the upper oil filling port (2401) is communicated with the arc oil storage groove (2403); the middle oil filling port (2402) is arranged at the lower end of the first bearing groove (2405); and the middle oil filling port (2402) is communicated with the cylinder body (23).

4. The top drive protector assembly according to claim 2, characterized in that: Adjustment washers (2106) are provided at both ends of the disc spring (2101), and the end surface and outer wall of the adjustment washer (2106) are both provided with oil grooves.

5. The top drive protector assembly according to claim 2, characterized in that: The middle diameter section of the spindle (21) is provided with an anti-drop annular groove (2103), the anti-drop half ring (2104) is sleeved on the anti-drop annular groove (2103), the anti-drop half ring (2104) is provided with an anti-drop outer conical surface (2105), the transmission outer cylinder (24) is provided with an anti-drop inner conical surface (2409), the anti-drop outer conical surface (2105) and the anti-drop inner conical surface (2409) are matched and have the same taper.

6. The top drive protector assembly according to claim 2, characterized in that: A limiting outer conical surface (2102) is also provided on the middle diameter section of the spindle (21), and a limiting inner conical surface (2408) is provided on the transmission outer cylinder (24). The limiting outer conical surface (2102) and the limiting inner conical surface (2408) cooperate to form a pressure limiting position.

7. The top drive protector assembly according to claim 2, characterized in that: The middle diameter section of the spindle (21) is also provided with a tension ring groove (2107), a tension ring (2108) is sleeved on the tension ring groove (2107), and a clamping ring (2109) is sleeved on the tension ring (2108) to clamp the tension ring (2108), a sliding sleeve (2110) is also sleeved on the tension ring (2108), and the tension ring (2108) and the sliding sleeve (2110) are slidably connected, an arc-shaped oil groove (2111) is provided on the end surface of the sliding sleeve (2110), and a straight oil groove (2112) is provided on the outer wall.

8. The top drive protector assembly according to claim 2, characterized in that: The piston (22) is sleeved with an outer hexagonal ring (2201), the outer hexagonal ring (2201) is provided with a locking nail hole (2202), and the anti-retraction screw (2203) cooperates with the locking nail hole (2202) to relatively fix the piston (22) and the spindle (21).

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