A sealed hydraulic following jar

Abstract

This invention discloses a sealed, follow-type hydraulic shock absorber, relating to the field of hydraulic shock absorbers. It includes a cylinder, a drill string, and a connector. A hydraulic cylinder is housed inside the cylinder, with an impact rod slidably mounted within it. An impact seat, cooperating with the impact rod, is located within the drill string. An upper and lower sleeve are fixedly connected between the impact rod and the hydraulic cylinder. Both the upper and lower sleeves contain a second sealing gasket, and a first sealing gasket is installed on the outer wall of the impact rod. As the pressure in the upper chamber increases, the arc-shaped sealing block on the outer wall provides a rigid seal to the hydraulic cylinder during the upward sliding of the impact rod. During this process, the first and second sealing gaskets are misaligned, which increases or decreases the damage to the two sets of sealing gaskets under high pressure. Simultaneously, the first sealing gasket slides into a groove to prevent excessive deformation of the two sets of sealing gaskets due to excessive compression from subsequent impact rod movements.

Description

Technical Field

[0001] This invention relates to the field of hydraulic shockers, specifically a sealed, follow-type hydraulic shocker. Background Technology

[0002] A hydraulic shock absorber is a downhole tool that uses a hydraulic system to control the impact force. It is mainly used to release stuck drill bits in oil drilling and well workover operations. It is also widely used in construction machinery, mining equipment and other fields. Its core principle is to convert the elastic potential energy stored in the drill string into instantaneous impact force through the pressure change and delayed release mechanism of hydraulic oil, so as to achieve efficient release.

[0003] In actual operation, when the drill bit at the output end encounters obstruction and needs to be released, the drill string is lifted, causing the impact force of the shocker to move upward. As the lifting force of the hook increases, the lifting of the drill string generates high pressure inside the hydraulic chamber. During the delay phase, the hydraulic oil flows slowly through a tiny channel. Once the energy accumulates to a critical point, it is released instantaneously, driving the mandrel to move at high speed and generate an impact. At this time, the shocker is slowly pulled open under the action of pre-tension and hydraulic resistance. Then, the damping control valve opens, and the hydraulic oil loses resistance and impacts the top impact seat. At this point, the shocker enters a free impact state, quickly sliding to the limit position within a fixed stroke. The impact mechanism strikes, generating a powerful upward impact force, thereby achieving the function of releasing the stuck drill bit.

[0004] In actual operation, the aforementioned structure uses a sealing gasket to seal the impact rod and hydraulic cylinder. Since stuck drill bits are frequently encountered during drilling, the sealing gasket may slide repeatedly. While it can maintain a seal under normal pressure, when the upper chamber of the hydraulic cylinder is under high pressure, the hydraulic oil pressure is highly likely to leak out through the gap in the sealing gasket, leading to hydraulic oil leakage. Furthermore, this leakage reduces the high pressure in the upper chamber, affecting the vibration force between the impact rod and the impact seat, thus impacting the subsequent unsticking effect on the drill bit and reducing the overall service life of the device. Summary of the Invention

[0005] Based on this, the purpose of this invention is to provide a sealed, follow-type hydraulic shock absorber to solve the technical problem that the sealing gasket under high pressure will cause hydraulic oil leakage, and the leakage of hydraulic oil will reduce the high pressure in the upper cavity, affecting the vibration force between the subsequent impact rod and the impact seat, thereby affecting the subsequent unjamming effect of the drill bit.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a sealed, follow-type hydraulic shock absorber, comprising a cylinder, a drill string, and a connector, wherein the upper end of the cylinder is elastically connected to the drill string, and the lower end is connected to the connector; a hydraulic cylinder is provided inside the cylinder, wherein an impact rod is slidably disposed inside the hydraulic cylinder; an impact seat that cooperates with the impact rod is disposed inside the drill string; and an upper sleeve and a lower sleeve are fixedly connected between the impact rod and the hydraulic cylinder.

[0007] Both the upper and lower housings are provided with a second sealing gasket, the outer wall of the impact rod is provided with a first sealing gasket, and an arc-shaped sealing block is provided on the impact rod at the bottom of the first sealing gasket. The top of the arc-shaped sealing block is rigidly sealed to the upper and lower housings respectively.

[0008] By adopting the above technical solution, the pressure in the upper cavity begins to increase. At the same time, during the upward sliding of the impact rod, the arc-shaped sealing block on the outer wall will rigidly seal the hydraulic cylinder, ensuring the pressure in the upper cavity under high pressure. During the upward sliding of the impact rod, the first sealing gasket will slide, causing the first sealing gasket and the second sealing gasket to be misaligned. This process will increase and reduce the damage to the two sets of sealing gaskets under high pressure. At the same time, the first sealing gasket will slide into the groove to prevent the subsequent impact rod from excessively squeezing and causing excessive deformation of the two sets of sealing gaskets, ensuring the sealing effect between the two sets of sealing gaskets.

[0009] The invention is further configured such that a fixing plate is provided at the top of the impact rod, and a pull plate that cooperates with the fixing plate is provided inside the drill string.

[0010] Preferably, during the process of lifting the drill string, the pull plate moves upward along with the drill string. When the top of the pull plate contacts the bottom of the fixed plate, the two are in a limited state. As the drill string continues to slide upward, the impact rod is driven to slide upward through the cooperation of the fixed plate and the pull plate.

[0011] The invention is further configured such that a piston is slidably disposed inside the hydraulic cylinder, wherein the piston is located on the outer wall of the impact rod, and the hydraulic cylinder is divided into an upper chamber and a lower chamber under the action of the piston. A pressure relief pipe and a return oil pipe are respectively disposed in the cylinder interlayer at the hydraulic cylinder, wherein a damping control valve is disposed in both the pressure relief pipe and the return oil pipe, and the two ends of the pressure relief pipe and the return oil pipe are respectively connected to the upper chamber and the lower chamber.

[0012] Preferably, during the upward sliding of the impact rod through the drill string, the piston slides upward within the hydraulic cylinder. During this process, the piston compresses the space in the upper chamber, and the hydraulic oil in the upper chamber is compressed. Due to the flow restriction of the damping control valve, the hydraulic oil cannot flow quickly into the lower chamber, which causes the pressure in the upper chamber to begin to rise. After the impact rod has finished impacting the impact seat, it will slide downward under the action of the elastic component and the weight of the impact rod itself. At this time, the damping control valve in the return oil pipe opens, allowing the hydraulic oil to flow back into the upper chamber, and the piston returns to its initial position, waiting for the next upward cycle.

[0013] The present invention is further configured such that an oil storage chamber is provided at the bottom of the hydraulic cylinder inside the cylinder, and an oil suction pipe and an oil discharge pipe are respectively connected between the oil storage chamber and the lower chamber, wherein an electrically controlled one-way valve is provided in both the oil suction pipe and the oil discharge pipe.

[0014] Preferably, during the upward sliding of the piston by the impact rod, a certain cavity is generated in its lower chamber. At this time, the hydraulic oil in the oil storage chamber is drawn into the lower chamber through the oil extraction pipe to avoid cavitation and ensure that the pressure in the lower chamber is within a certain range. Subsequently, the hydraulic oil in the upper chamber is discharged into the lower chamber through the opening of the damping control valve. After the piston is impacted, some hydraulic oil will be discharged back into the oil storage chamber through the oil drain pipe for subsequent use.

[0015] The present invention is further configured such that an energy storage component is provided at the top of the hydraulic cylinder, and the energy storage component itself is detachable.

[0016] Preferably, the energy storage component can absorb some of the pressure fluctuations, thereby preventing the upper cavity pressure from rising suddenly and damaging the seals, and improving the overall service life.

[0017] The present invention is further configured such that both the upper and lower housings are provided with slots, wherein the slots are located on the top of the second sealing gasket.

[0018] Preferably, the first sealing gasket slides into the slot along with the impact rod to prevent excessive compression by the subsequent impact rod, which would cause excessive deformation of the two sets of sealing gaskets and ensure the sealing effect between the two sets of sealing gaskets. At the same time, during the impact of the impact rod, the slot design prevents the first sealing gasket from absorbing part of the impact force, ensuring that the impact force is stably delivered to the drill bit at the bottom.

[0019] The present invention is further configured such that the drill string and the cylinder are connected by a snap-fit ​​connection, and an elastic component is connected between the drill string and the cylinder.

[0020] Preferably, during the process of lifting the drill string, the elastic component on its inner side is in a stretched state. When it continues to slide, it will lift the internal impact rod. After the impact rod has finished its impact, the impact rod will drive the piston to slide downward under the action of the reset force of the elastic component and the weight of the impact rod itself.

[0021] The present invention is further configured such that the connector and the cylinder are welded together, and the outer wall of the connector is provided with external threads.

[0022] Preferably, the welded configuration ensures that the drill bit can provide stable drilling force during the driving process, and the external thread configuration ensures that the drill bit can be disassembled, facilitating subsequent maintenance and replacement, and improving the overall service life of the device.

[0023] The present invention is further configured such that the energy storage component includes a bladder-type accumulator and a frame, wherein the frame is located at the top inside the hydraulic cylinder, and a bladder-type accumulator is disposed on the frame, the bladder-type accumulator being filled with nitrogen.

[0024] Preferably, nitrogen is filled into the bladder-type accumulator at a pre-charge pressure of 10 MPa. As the pressure in the upper chamber gradually increases, the bladder-type accumulator automatically contracts when the pressure exceeds the nitrogen pre-charge pressure. At this time, the hydraulic oil in the accumulator is pressurized synchronously with the upper chamber, which is equivalent to expanding the energy storage space of the upper chamber and preventing the cylinder from cracking due to excessive pressure.

[0025] The present invention is further configured such that the outer wall of the lower casing and the inner wall of the oil storage cavity are smooth.

[0026] Preferably, the smooth surface facilitates stable flow of hydraulic oil inside and prevents the hydraulic oil from condensing into lumps on the inner wall.

[0027] In summary, the present invention has the following main beneficial effects:

[0028] This invention connects second sealing gaskets to the inner walls of the upper and lower shells respectively. Under normal pressure, the hydraulic cylinder is sealed by the first sealing gasket. When the impact rod moves upward through the drill string, the piston slides upward in the hydraulic cylinder. At this time, the hydraulic oil in the upper chamber is compressed. Due to the flow restriction of the damping control valve, the oil cannot flow to the lower chamber quickly, thus increasing the pressure in the upper chamber. At the same time, the arc-shaped sealing block on the outer wall rigidly seals the hydraulic cylinder during the upward sliding of the impact rod, ensuring the pressure in the upper chamber under high pressure and improving the impact effect of the subsequent impact rod.

[0029] This invention places a first sealing gasket on an impact rod, with second sealing gaskets located inside the upper and lower housings respectively. As the impact rod slides upward, it causes the first sealing gasket to slide, resulting in a misalignment between the first and second sealing gaskets. This process increases or decreases the damage to the two sets of sealing gaskets caused by high pressure. At the same time, the first sealing gasket slides into the groove, preventing excessive compression by the subsequent impact rod from causing excessive deformation of the two sets of sealing gaskets, ensuring the sealing effect between the two sets of sealing gaskets and extending the overall service life of the device.

[0030] This invention features a slot located above the first sealing gasket within the upper and lower housings. When the damping control valve is fully opened to release pressure, the impact rod slides upwards. During this process, the first and second sealing gaskets work together to ensure flexible contact between the impact rod and the upper and lower housings, effectively preventing rigid wear. This ensures that the arc-shaped sealing block maintains a certain level of sealing for the hydraulic cylinder even during repeated impacts and sliding. Furthermore, when the impact rod contacts the impact seat, the slot design prevents the first sealing gasket from absorbing part of the impact force, ensuring that the impact force is stably delivered to the drill bit at the bottom. Attached Figure Description

[0031] Figure 1 This is a perspective view of the present invention;

[0032] Figure 2 This is a schematic diagram of the impact rod of the present invention in its conventional state;

[0033] Figure 3 This is a schematic diagram of the impact seat structure of the present invention;

[0034] Figure 4 For the present invention Figure 2 Enlarged view of A in the middle;

[0035] Figure 5 For the present invention Figure 2 Enlarged view of B in the middle;

[0036] Figure 6 This is an internal view of the cylinder and impact rod of the present invention;

[0037] Figure 7 This is a cross-sectional view of the cylindrical body of the present invention;

[0038] Figure 8 For the present invention Figure 7 Enlarged view of C;

[0039] Figure 9 This is a schematic diagram of the impact rod and hydraulic assembly structure of the present invention;

[0040] Figure 10 This is a schematic diagram of the impact rod structure of the present invention;

[0041] Figure 11 This is a schematic diagram of the flow channel structure of the damping control valve of the present invention;

[0042] Figure 12 This is a schematic diagram of the impact rod in the delayed state of the present invention.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Cylinder; 2. Drill string; 3. Connector; 4. Impact seat; 5. Upper chamber; 6. Pressure relief pipe; 7. Lower chamber; 8. Suction pipe; 9. Lower sleeve; 10. Return pipe; 11. Piston; 12. Damping control valve; 13. Discharge pipe; 14. Oil storage chamber; 15. Pull plate; 16. First sealing gasket; 17. Hydraulic cylinder; 18. Energy storage assembly; 19. Arc-shaped sealing block; 20. Groove; 21. Second sealing gasket; 22. Fixing plate; 23. Upper sleeve; 24. Impact rod. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0046] The embodiments of the present invention will now be described.

[0047] Example 1: Please refer to Figures 1-12 The sealed, follow-type hydraulic shock absorber shown includes a cylinder 1, a drill string 2, a connector 3, an impact rod 24, a reset mechanism, a shock mechanism, and a circulation mechanism. The upper end of the cylinder 1 is elastically connected to the drill string 2, and the lower end is connected to the connector 3. A drill bit is provided on the outer wall of the connector 3. When the drill bit gets stuck during operation, the drill string 2 is lifted by the hook, causing the drill string 2 to slide upward. A fixing plate 22 is provided on the top of the impact rod 24. A pull plate 15 that cooperates with the fixing plate 22 is provided inside the drill string 2. During the lifting of the drill string 2, the pull plate 15 moves upward with the drill string 2. When the top of the pull plate 15 contacts the bottom of the fixing plate 22, the two are in a limited state. As the drill string 2 continues to slide upward, the impact rod 24 is driven to slide upward by the cooperation of the fixing plate 22 and the pull plate 15.

[0048] A hydraulic cylinder 17 is installed inside the cylinder 1. An impact rod 24 is slidably installed inside the hydraulic cylinder 17, and a piston 11 is slidably installed inside the hydraulic cylinder 17. The piston 11 is located on the outer wall of the impact rod 24, and under the action of the piston 11, the hydraulic cylinder 17 is divided into an upper chamber 5 and a lower chamber 7. An upper sleeve 23 and a lower sleeve 9 are fixedly connected between the impact rod 24 and the hydraulic cylinder 17. A second sealing gasket 21 is installed inside both the upper sleeve 23 and the lower sleeve 9. A first sealing gasket 16 is installed on the outer wall of the impact rod 24. Under normal pressure, the hydraulic oil in the hydraulic cylinder 17 is sealed by the second sealing gasket 21 and the first sealing gasket 16.

[0049] As the impact rod 24 slides upward through the drill string 2, the piston 11 slides upward within the hydraulic cylinder 17. During this process, the piston 11 compresses the space of the upper chamber 5, compressing the hydraulic oil within the upper chamber 5. Simultaneously, a pressure relief pipe 6 and a return oil pipe 10 are respectively installed in the interlayer of the cylinder 1 at the location of the hydraulic cylinder 17. Both the pressure relief pipe 6 and the return oil pipe 10 are equipped with damping control valves 12, and their ends are connected to the upper chamber 5 and the lower chamber 7, respectively. Because the damping control valve 12 restricts the flow of hydraulic oil, it cannot flow quickly into the lower chamber, causing the pressure in the upper chamber 5 to begin to rise. Furthermore, an arc-shaped sealing block 19 is installed at the bottom of the first sealing gasket 16 on the impact rod 24. The top of the arc-shaped sealing block 19 is rigidly sealed to the upper sleeve 23 and the lower sleeve 9, effectively preventing leakage of the hydraulic oil inside. This ensures the pressure within the upper chamber 5 under high pressure, improving the impact effect of the subsequent impact rod 24.

[0050] Furthermore, an oil storage chamber 14 is provided at the bottom of the hydraulic cylinder 17 inside the cylinder 1. An oil suction pipe 8 and an oil discharge pipe 13 are connected between the oil storage chamber 14 and the lower chamber 7, respectively. Both the oil suction pipe 8 and the oil discharge pipe 13 are equipped with an electrically controlled check valve. During the process of the piston 11 sliding upward through the impact rod 24, a certain cavity will be generated in the lower chamber 7. At this time, the electrically controlled check valve in the oil suction pipe 8 is opened to draw the hydraulic oil in the oil storage chamber 14 into the lower chamber 7 to avoid cavitation and ensure that the pressure in the lower chamber is within a certain range. When the pressure in the upper chamber 5 reaches a certain value, the damping control valve 12 will be fully opened, and the hydraulic oil resistance between the upper chamber 5 and the lower chamber 7 will disappear instantly. At this time, the cylinder enters the energy free release state. The hydraulic oil under high pressure will be discharged into the lower chamber 7 through the pressure relief pipe 6 and impact the piston 11 to bounce upward. An impact seat 4 that cooperates with the impact rod 24 is provided in the drill string 2. The impact rod 24 will impact the impact seat 4 at the top to generate a certain shock force.

[0051] After the impact is completed, the piston 11 will slide downward by the impact rod 24 itself. At this time, the damping control valve 12 in the return oil pipe 10 opens, so that some hydraulic oil will flow back to the upper chamber. At the same time, the drain oil pipe 13 will cause some hydraulic oil to flow back to the oil storage chamber, and the piston 11 returns to the initial position, waiting for the next lifting cycle.

[0052] For details regarding the above embodiments, please refer to [link / reference]. Figure 2 and Figure 5 The drill string 2 and the cylinder 1 are connected by a snap-fit ​​mechanism, and an elastic component is connected between the drill string 2 and the cylinder 1. During the upward movement of the drill string 2, the elastic component inside is in a stretched state. When it continues to slide, it will lift the internal impact rod 24. After the impact rod 24 has completed its impact, the impact rod 24 will drive the piston 11 to slide downward due to the reset force of the elastic component and the weight of the impact rod 24 itself.

[0053] For details regarding the above embodiments, please refer to [link / reference]. Figure 4 The energy storage component 18 includes a bladder-type accumulator and a frame. The frame is located at the top inside the hydraulic cylinder 17, and the bladder-type accumulator is installed on the frame. The bladder-type accumulator is filled with nitrogen. By filling the bladder-type accumulator with nitrogen, the pre-charge pressure of the nitrogen is 10 MPa. When the pressure in the upper chamber 5 gradually increases, when the pressure exceeds the nitrogen pre-charge pressure, the bladder-type accumulator automatically contracts. At this time, the hydraulic oil in the accumulator is pressurized synchronously with the upper chamber 5, which is equivalent to expanding the energy storage space of the upper chamber and preventing the cylinder 1 from cracking due to excessive pressure.

[0054] Example 2: Please refer to Figure 7 and Figure 8 The sealed, follow-type hydraulic shock absorber shown has an overall structure similar to that of Embodiment 1. Both the upper housing 23 and the lower housing 9 have slots 20, with the slots 20 located at the top of the second sealing gasket 21. The first sealing gasket 16 slides into the slot 20 along with the impact rod 24, preventing excessive compression by the subsequent impact rod 24 that could cause excessive deformation of the two sets of sealing gaskets, thus ensuring a good seal between the two sets of sealing gaskets. Simultaneously, during the impact of the impact rod 24, the slots 20 prevent the first sealing gasket 16 from absorbing part of the impact force, ensuring a stable delivery of the impact force to the drill bit at the bottom.

[0055] In practical operation, the present invention is used by connecting the drill bit via the connector 3. When a stuck drill bit occurs during drilling, the operator lifts the drill string 2 using the hook. At this time, the drill string 2 is stretched by the elastic component. Then, with the cooperation of the fixing plate 22 and the pull plate 15, the impact rod 24 slides upward. During this process, the impact rod 24 drives the piston 11 on the outer wall to slide upward in the hydraulic cylinder 17. At this time, the space of the upper chamber 5 in the hydraulic cylinder 17 is compressed. Under the action of the damping control valve 12, the hydraulic oil cannot flow to the lower chamber 7 quickly. At this time, the pressure in the upper chamber 5 begins to rise. During the upward sliding of the impact rod 24, the arc-shaped sealing block 19 on its outer wall will rigidly seal the upper sleeve 23 and the lower sleeve 9. This process ensures that no hydraulic oil leakage occurs under high pressure.

[0056] As the pressure inside the upper chamber 5 increases, when it reaches a certain value, its damping control valve 12 is fully open. At this time, the pressure of the hydraulic oil in the upper chamber 5 is completely released, so that the high-pressure hydraulic oil will be discharged into the lower chamber 7 through the damping control valve 12. The high-pressure hydraulic oil will impact the piston 11, causing the piston 11 to push the impact rod 24 upward. When the impact rod 24 reaches the fixed point, it will contact the impact seat 4 and have a rigid collision. This impact force is transmitted along the impact rod 24 to the stuck drill bit, overcoming the stuck force of the drill bit to achieve unblocking. After the impact, the piston 11 is reset and slid downward under the action of the elastic component. During this process, the internal hydraulic oil will be discharged into the upper chamber 5 through the return oil pipe 10, waiting for the next lifting cycle. If the unblocking is not completed in one impact, the above process is repeated.

[0057] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the invention, but such modifications, substitutions, and variations are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A sealed, follow-type hydraulic shock absorber, comprising a cylinder (1), a drill string (2), and a connector (3), wherein the upper end of the cylinder (1) is elastically connected to the drill string (2), and the lower end is connected to the connector (3), characterized in that: The cylinder (1) is equipped with a hydraulic cylinder (17), and an impact rod (24) is slidably arranged inside the hydraulic cylinder (17). An impact seat (4) that cooperates with the impact rod (24) is arranged inside the drill string (2). An upper sleeve (23) and a lower sleeve (9) are fixedly connected between the impact rod (24) and the hydraulic cylinder (17). The upper shell (23) and the lower shell (9) are both provided with a second sealing gasket (21). The outer wall of the impact rod (24) is provided with a first sealing gasket (16). An arc-shaped sealing block (19) is also provided on the impact rod (24) at the bottom of the first sealing gasket (16). The top of the arc-shaped sealing block (19) is rigidly sealed to the upper shell (23) and the lower shell (9) respectively.

2. The sealed, follow-type hydraulic shock absorber according to claim 1, characterized in that: The top of the impact rod (24) is provided with a fixing plate (22), and the drill string (2) is provided with a pull plate (15) that cooperates with the fixing plate (22).

3. A sealed, follow-type hydraulic shock absorber according to claim 1, characterized in that: A piston (11) is slidably disposed inside the hydraulic cylinder (17), wherein the piston (11) is located on the outer wall of the impact rod (24), and the hydraulic cylinder (17) is divided into an upper chamber (5) and a lower chamber (7) under the action of the piston (11). A pressure relief pipe (6) and a return oil pipe (10) are respectively disposed in the interlayer of the cylinder (1) at the hydraulic cylinder (17). A damping control valve (12) is disposed in both the pressure relief pipe (6) and the return oil pipe (10), and the two ends of the pressure relief pipe (6) and the return oil pipe (10) are respectively connected to the upper chamber (5) and the lower chamber (7).

4. A sealed, follow-type hydraulic shock absorber according to claim 3, characterized in that: An oil storage chamber (14) is provided at the bottom of the hydraulic cylinder (17) inside the cylinder (1). An oil suction pipe (8) and an oil discharge pipe (13) are respectively connected between the oil storage chamber (14) and the lower chamber (7). Both the oil suction pipe (8) and the oil discharge pipe (13) are equipped with an electrically controlled check valve.

5. A sealed, follow-type hydraulic shock absorber according to claim 1, characterized in that: The top of the hydraulic cylinder (17) is provided with an energy storage component (18), which is detachable.

6. A sealed, follow-type hydraulic shock absorber according to claim 1, characterized in that: Both the upper shell (23) and the lower shell (9) are provided with slots (20), wherein the slots (20) are located on the top of the second sealing gasket (21).

7. A sealed, follow-type hydraulic shock absorber according to claim 1, characterized in that: The drill string (2) and the cylinder (1) are connected by a snap-fit ​​mechanism, and an elastic component is connected between the drill string (2) and the cylinder (1).

8. A sealed, follow-type hydraulic shock absorber according to claim 1, characterized in that: The connector (3) is welded to the cylinder (1), and the outer wall of the connector (3) is provided with external threads.

9. A sealed, follow-type hydraulic shock absorber according to claim 5, characterized in that: The energy storage assembly (18) includes a bladder-type accumulator and a frame, wherein the frame is located at the top inside the hydraulic cylinder (17), and a bladder-type accumulator is provided on the frame, the bladder-type accumulator being filled with nitrogen.

10. A sealed, follow-type hydraulic shock absorber according to claim 4, characterized in that: The outer wall of the lower casing (9) and the inner wall of the oil storage cavity (14) are smooth.

Images