Improved digital double-seat active slip system

Abstract

The utility model discloses an improved digital double-seat active slip system. The improved digital double-seat active slip system comprises an axial power slip assembly, a data acquisition system, an upper digital flange, a lower digital flange, a spraying device and the like. The upper digital flange comprises an upper flange and an upper load sensor, the lower digital flange comprises a lower flange and a lower load sensor, and the upper load sensor and the lower load sensor are both connected with the data acquisition system; the slip system further comprises a guide column, and the two ends of the guide column penetrate through the two ends of the axial power slip assembly respectively and then are fixedly connected with the upper flange and the lower flange respectively. According to the system, single-seat movement is changed into double-seat movement, the clamping force of the slip is actively controlled, one set of device can effectively control a pipe column to be ejected upwards to fly out or fall into a well, the operation process is simplified, and the slip insert cleaning and cooling functions are achieved; operation parameters such as the stress size and direction of the pipe column are obtained in real time, and digital upgrading of the slip system is achieved for the first time.

Description

Technical Field

[0001] The utility model belongs to the field of oil and gas drilling equipment, and specifically relates to an improved digital double-seat active slip system. Background Art

[0002] In the process of well construction and maintenance, petroleum engineering cannot do without the drilling and completion, well repair operation pipes, including drill pipes and tubing, which requires the use of wellhead tools to hold the pipe. As the main pipe holding tool for wellhead operations, slips are widely used in the drilling and completion process because of their simple structure and convenient operation. According to the power source of slips, there are two types: manual slips and power slips (including pneumatic and hydraulic slips), and their working mechanism is to use the wedge working principle and friction law. In the past, because only the gravity of the suspended pipe was needed, the back of the slip body was designed with a certain tapered inclined surface, corresponding to the turntable core or slip seat. Under the action of the gravity of the pipe, the slip body slides relatively along the inclined surface, radially closes the slip body, and the slip tooth plate and the pipe produce static friction, realizing the function of holding the pipe. In order to increase the slip friction coefficient, a special slip tooth plate was designed according to the friction law. However, when the operating pipe string is deeper or the top force is greater, the pipe string is subjected to greater force, and slip tooth marks will be left on the surface of the pipe string. Although the purpose of holding the pipe string is achieved, the integrity of the pipe string is also damaged, which buries a safety hazard for later production.

[0003] Although the prior art solves the above problems, for example, CN220621791U discloses an axially loaded slip that can lock the pipe string at both ends of the slip tooth plate, the prior art slips still have the following problems.

[0004] 1. When the slip teeth fail or the clamping state is changed by external force, the pipe string will fly out or fall through the slips, causing safety hazards.

[0005] 2. The axially loaded slip is a structure with one fixed and one movable. Although it can lock the two ends of the slip tooth plate, the slip tooth is still single-piece and unidirectional, and cannot hold the bidirectional force-bearing pipe string. Especially when used for pressure operation, two sets of such slip systems are still required to be installed, and the operator needs to control them separately, which is complicated to operate.

[0006] 3. When the existing slip assembly is retracted, only the slip bushing in the axially loaded slip system forms a bidirectional cone, but the aperture is large and does not have the function of preventing the pipe string from flying out or falling into the well. If the slip teeth fail, the pipe string will still be out of control. The other slips do not have a reverse locking cone.

[0007] 4. The existing slip working process cannot directly display the magnitude and direction of the force on the pipe string, and does not meet the technical requirements of modern industry for digital equipment.

[0008] 5. The slip teeth have no self-cleaning function and cannot ensure that the slip teeth are always in good condition. The dirt on the surface of the pipe fills the groove of the slip teeth, causing the clamping failure and causing the operator to misjudge. Utility Model Content

[0009] In order to solve the above problems existing in the prior art, the utility model provides an improved digital two-seat active slip system.

[0010] The technical solution adopted by the utility model is:

[0011] An improved digital two-seat active slip system, the slip system comprising an axial power slip assembly, a data acquisition system, an upper digital flange, and a lower digital flange; the upper digital flange comprises an upper flange and an upper load sensor, and the lower digital flange comprises a lower flange and a lower load sensor; the upper load sensor and the lower load sensor are both connected to the data acquisition system so that the data acquisition system can collect operating data of the slip system; the slip system also comprises a guide column to guide the slip assembly to automatically move up and down; the two ends of the guide column respectively pass through the two ends of the axial power slip assembly and are fixedly connected to the upper flange and the lower flange respectively, so as to realize the control of bidirectional force on the pipe column.

[0012] Preferably, the data acquisition system includes a data acquisition unit, a PLC control unit, an on-site control execution unit, a display screen, an industrial computer, and a data center.

[0013] Preferably, the axial power cava assembly includes an upper flange cava seat, a lower flange cava seat, four groups of cava bushings, eight groups of cava tooth plates, lubrication grooves, buffer pads, and a power cylinder; every two groups of cava tooth plates are symmetrically installed on the surface of each group of cava bushings in an upper and lower manner; the outer surface of each group of cava bushings is a double-conical surface that is symmetrical in the upper and lower directions, and the inner surfaces of the upper flange cava seat and the lower flange cava seat are respectively provided with conical surfaces that match the double-conical surfaces, and four groups of cava bushings are arranged between the upper flange cava seat and the lower flange cava seat; the two ends of the power cylinder are respectively connected to the upper flange cava seat and the lower flange cava seat.

[0014] Preferably, four guide columns are provided, and two ends of each guide column respectively pass through the upper flange slip seat and the lower flange slip seat and are fixedly connected to the upper flange and the lower flange respectively.

[0015] Preferably, the power cylinders are arranged in two groups, and each group of the power cylinders is provided with a hydraulic sensor.

[0016] Preferably, the data acquisition unit is connected to the upper load sensor, the lower load sensor and the hydraulic sensor respectively.

[0017] Preferably, a spray device is provided inside the upper flange and inside the lower flange respectively. The spray device is a circular ring structure with a nozzle and is connected to a liquid supply system.

[0018] Preferably, a plurality of the lubrication grooves are respectively arranged on the outer surface of each group of the slip bushings, wherein a lubrication strip or lubricant is arranged in each of the lubrication grooves.

[0019] Preferably, several groups of the buffer pads are respectively arranged on the end surface of each group of the slip bushings.

[0020] Compared with the prior art, the utility model has the following beneficial effects.

[0021] 1. The improved digital two-seat active slip system applies digital information technology for the first time, which measures the force and direction of the pipe string in real time, and actively controls the slip holding force parameters, thus providing necessary means for guiding the pipe string lifting and lowering operations, protecting the integrity of the pipe string, and automating and intelligentizing the equipment.

[0022] 2. The upper and lower flanges of the improved digital two-seat active slip system can effectively control the force on the pipe column, and will not lose the holding force due to the change of direction; the upper and lower flanges are the upper and lower dead points of the slip assembly stroke. Therefore, when the assembly moves to the dead point, the clamping force is generated again, realizing the function of the slip to clamp the pipe column in double and two-way directions, improving the reliability of the slip system, and eliminating the need for the operator to judge the force direction of the pipe column in advance before operating the corresponding slip, simplifying the operating procedure.

[0023] 3. The upper and lower flanges of the improved digital two-seat active slip system are equipped with force test sensors, which can obtain the force magnitude in real time when the slip assembly contacts the upper and lower dead points. Its structure is the key to realizing digital slip technology.

[0024] 4. The guide column of the improved digital two-seat active slip system connects and fixes the upper and lower flanges, forming a closed frame with the upper and lower flanges, restricting the movement range of the slip assembly, providing the necessary conditions for the slips to be retracted to form a double cone, and further improving the safety of the slip system.

[0025] 5. For the first time, an information platform for the operation parameters of the slip system was built, and a method was proposed to determine whether the slip is stuck in the pipe string by comparing the calculated value with the theoretical test value, which provided ideas for the digital operation of oil and gas fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a three-dimensional diagram of the utility model.

[0027] Figure 2 It is a partial cross-sectional view of the utility model.

[0028] Figure 3 It is a schematic diagram of the data acquisition system of the utility model.

[0029] Figure 4 It is a schematic diagram of the axial power slip assembly in the utility model in a loosened state.

[0030] Figure 5 It is a schematic diagram of the axial power slip assembly of the utility model in a clamped state.

[0031] Figure 6 It is a working schematic diagram of the utility model when the pipe column is in the upper lifting state.

[0032] Figure 7 It is a working schematic diagram of the utility model when the pipe column is in a load-bearing state.

[0033] Figure 8 It is a schematic diagram of the spray device in the utility model.

[0034] Fig. 9 It is a schematic diagram of the axial power slip assembly being in a clamped state and the slip bushing being collapsed to form a frustum.

[0035] Fig.10 It is a working schematic diagram of the utility model when the axial power slip assembly is stuck in the coupling position.

[0036] Fig.11 for Fig.10 A schematic diagram of the working of the utility model when the coupling in the utility model slides out of the axial power slip assembly.

[0037] In the figure, 100. axial power slip assembly, 200. data acquisition system, 300. upper digital flange, 400. lower digital flange, 1. upper flange, 2. lower flange, 3. lower load sensor, 4. guide column, 5. spray device, 6. upper flange slip seat, 7. lower flange slip seat, 8. slip bushing, 9. slip tooth plate, 10. lubrication groove, 11. buffer pad, 12. power cylinder, 13. hydraulic sensor, 14. data acquisition unit, 15. PLC control unit, 16. on-site control execution unit, 17. display screen, 18. industrial computer, 19. data center, 20. upper load sensor, 21. pipe column, 22. coupling. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model, that is, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the utility model provided in the accompanying drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0040] Combine the following Figure 1-11 The specific implementation mode of the utility model is described.

[0041] The present embodiment provides an improved digital two-seat active cava system, including an axial power cava assembly 100, a data acquisition system 200, an upper digital flange 300, and a lower digital flange 400; the upper digital flange 300 includes an upper flange 1 and an upper load sensor 20, and the lower digital flange 400 includes a lower flange 2 and a lower load sensor 3; the upper load sensor 20 and the lower load sensor 3 are both connected to the data acquisition system 200 so that the data acquisition system 200 collects data from the load sensors.

[0042] The improved digital two-seat active slip system further comprises a plurality of guide posts 4, preferably four or more guide posts 4.

[0043] The two ends of the guide column 4 pass through the two ends of the axial power slip assembly 100 and are fixedly connected to the upper flange 1 and the lower flange 2 respectively.

[0044] The guide column 4 can be used as a support rod for the upper digital flange 300 and the lower digital flange 400 , and can also be used as a movement guide rod for the axial power slip assembly 100 .

[0045] The axial power slip assembly 100 includes an upper flange slip seat 6 , a lower flange slip seat 7 , four groups of slip bushings 8 , eight groups of slip tooth plates 9 , a lubrication groove 10 , a buffer pad 11 , and a power cylinder 12 .

[0046] Two ends of the guide column 4 pass through the upper flange slip seat 6 and the lower flange slip seat 7 respectively and are fixedly connected to the upper flange 1 and the lower flange 2 respectively.

[0047] Every two groups of slip tooth plates 9 are symmetrically installed on the inner surface of each group of slip bushings 8.

[0048] A spray device 5 is also provided inside the upper flange 1 and inside the lower flange 2. The spray device 5 is a ring structure with a nozzle and is connected to the liquid supply system. The spray device 5 cleans or cools the axial power slip assembly 100 by spraying cleaning liquid or cooling liquid.

[0049] The outer surface of each group of slip bushings 8 is a double cone surface that is symmetrical up and down. The inner surfaces of the upper flange slip seat 6 and the lower flange slip seat 7 are respectively provided with cone surfaces that match the above double cone surfaces. The four groups of slip bushings 8 are located between the upper flange slip seat 6 and the lower flange slip seat 7.

[0050] A plurality of lubrication grooves 10 are respectively arranged on the outer surface of each group of slip bushings 8 , wherein a lubrication strip or lubricant is arranged in each lubrication groove 10 .

[0051] A plurality of groups of buffer pads 11 are respectively arranged on the end surface of each group of slip bushings 8, which can effectively prevent the pipe string from losing control and colliding with the slips to generate sparks.

[0052] The two ends of the power cylinder 12 are connected to the upper flange slip seat 6 and the lower flange slip seat 7 respectively. The power cylinder 12 can drive the upper flange slip seat 6 and the lower flange slip seat 7 to move toward or in the opposite direction along the guide column 4, and further drive the four groups of slip bushings 8 to be gathered or separated, so as to realize the axial power slip assembly 100 to hold or loosen the pipe column. In addition, since the four groups of slip bushings 8 are arranged between the upper flange slip seat 6 and the lower flange slip seat 7, the axial power slip assembly 100 can effectively hold the pipe column whether the pipe column is in a flying out or falling state.

[0053] The power cylinders 12 are preferably provided in at least two groups, and each group of power cylinders 12 is provided with a hydraulic sensor 13, which can monitor the force of the power cylinders 12 in real time. The hydraulic sensor 13 is connected to the data acquisition system 200 so that the data acquisition system 200 collects data from the hydraulic sensor 13 and calculates the clamping force of the axial power slip assembly 100 through the data from the hydraulic sensor 13.

[0054] The data acquisition system 200 includes a data acquisition unit 14, a PLC control unit 15, a field control execution unit 16, a display screen 17, an industrial computer 18, and a data center 19. The data acquisition unit 14 is connected to the upper load sensor 20, the lower load sensor 3, and the hydraulic sensor 13 respectively.

[0055] The working principle of the utility model is as follows.

[0056] First embodiment.

[0057] When the pipe column 21 is in normal working state, the piston of the power cylinder 12 extends, which drives the upper flange slip seat 6 and the lower flange slip seat 7 to move in the opposite direction along the guide column 4, and further drives the four groups of slip bushings 8 to separate. Figure 4 As shown, the axial power slip assembly 100 is loosened to the pipe string, and the pipe string can be raised and lowered normally.

[0058] Second embodiment.

[0059] When the pipe string 21 is in a load-bearing state, Figure 7 As shown, the piston of the power cylinder 12 is retracted, which drives the upper flange slip seat 6 and the lower flange slip seat 7 to move toward each other along the guide column 4, and further drives the four groups of slip bushings 8 to retract, as shown in FIG. Figure 5 As shown, the axial power slip assembly 100 can hold the pipe string tightly. At this time, the hydraulic sensor 13 monitors the force of the power cylinder 12 in real time.

[0060] In this state, the pipe column will move downward with the axial power slip assembly 100 until the lower flange slip seat 7 abuts against the lower flange 2, and the axial power slip assembly 100 moves to the bottom dead center. In addition, when the lower flange slip seat 7 abuts against the lower flange 2, the lower flange 2 will form a force on the lower flange slip seat 7. Under this force, the four groups of slip bushings 8 will be further retracted, that is, the axial power slip assembly 100 will form a re-clamping force on the pipe column, realizing a double clamping of the pipe column and improving the reliability of the slip system. At this time, the lower load sensor 3 monitors the downward pressure of the axial power slip assembly 100 that clamps the pipe column (that is, the pressure of the lower flange slip seat 7 on the lower flange 2) and the force direction of the pipe column in real time.

[0061] The data acquisition system 200 collects data from the lower load sensor 3 and the hydraulic sensor 13 in real time, and determines whether the pipe string is in a load-bearing state and whether the axial power slip assembly 100 is holding the pipe string tightly according to the pressure monitored by the lower load sensor 3. Specifically, if the pressure monitored by the lower load sensor 3 is less than the sum of the theoretical gravity of the pipe string and the slip at that location, it is determined that the axial power slip assembly 100 does not hold the pipe string tightly. At this time, the piston retraction force of the power cylinder 12 is gradually increased according to the data of the hydraulic sensor 13 until the pressure monitored by the lower load sensor 3 is close to the sum of the theoretical gravity of the pipe string and the slip at that location. If the pressure monitored by the lower load sensor 3 is close to the sum of the theoretical gravity of the pipe string and the slip at that location, it is determined that the axial power slip assembly 100 has held the pipe string tightly. At this time, there is no need to adjust the force of the power cylinder 12.

[0062] Third embodiment.

[0063] When the pipe column 21 is in the top-up state, Figure 6As shown, the piston of the power cylinder 12 is retracted, which drives the upper flange slip seat 6 and the lower flange slip seat 7 to move toward each other along the guide column 4, and further drives the four groups of slip bushings 8 to retract, as shown in FIG. Figure 5 As shown, the axial power slip assembly 100 can hold the pipe string tightly. At this time, the hydraulic sensor 13 monitors the force of the power cylinder 12 in real time.

[0064] In this state, the pipe string will move upward with the axial power slip assembly 100 until the upper flange slip seat 6 abuts against the upper flange 1, and the slip assembly moves to the top dead center. In addition, when the upper flange slip seat 6 abuts against the upper flange 1, the upper flange 1 will form a force on the upper flange slip seat 6. Under this force, the four groups of slip bushings 8 will be further retracted, that is, the axial power slip assembly 100 will form a re-clamping force on the pipe string, realizing a double clamping of the pipe string and improving the reliability of the slip system. At this time, the upper load sensor 20 monitors the upper pressure of the axial power slip assembly 100 (i.e., the pressure of the upper flange slip seat 6 on the upper flange 1) and the force direction of the pipe string in real time.

[0065] The data acquisition system 200 collects data from the upper load sensor 20 and the hydraulic sensor 13 in real time, and judges whether the pipe string is in the upper push state and whether the axial power slip assembly 100 is holding the pipe string tightly according to the pressure monitored by the upper load sensor 20. Specifically, if the pressure monitored by the upper load sensor 20 is less than the theoretical pressure of the axial power slip assembly 100 on the upper flange 1 at that location, it is judged that the axial power slip assembly 100 does not hold the pipe string tightly. At this time, the piston retraction force of the power cylinder 12 is gradually increased according to the data of the hydraulic sensor 13 until the pressure monitored by the upper load sensor 20 is close to the theoretical pressure of the axial power slip assembly 100 on the upper flange 1 at that location. If the pressure monitored by the upper load sensor 20 is close to the theoretical pressure of the axial power slip assembly 100 on the upper flange 1 at that location, it is judged that the axial power slip assembly 100 has held the pipe string tightly, and at this time, there is no need to adjust the force of the power cylinder 12.

[0066] Fourth embodiment.

[0067] The four groups of slip bushings 8 are gathered together to form a frustum, such as Fig. 9 As shown, the diameter of the center hole of the truncated cone is smaller than the outer diameter of large-sized downhole tools such as the pipe string coupling 22. The top surface of the truncated cone or the end surface of the slip plate restricts the passage of large-sized downhole tools such as the pipe string coupling 22, that is, restricts the failure and fall of the pipe string 21. The end surface buffer pad 11 provided on each group of slip bushings 8 can effectively prevent the pipe string from losing control and colliding with the slip to generate sparks.

[0068] The design of the truncated cone formed by the four groups of slip bushings 8 can effectively prevent the pipe string from flying out or falling into the well, and provides a new control method for pipe string blowout prevention.

[0069] Fifth embodiment.

[0070] When the axial power cava assembly 100 is stuck in the wrong position, the improved digital two-seat active cava system of this embodiment also has an automatic error correction function. Due to the unique structural design of the axial power cava assembly 100, the cava body engagement area is twice that of the existing cava, providing sliding space for misplaced pipe column positions (for example, stuck in the pipe column coupling 22). The hollow frustum formed by the axial power cava assembly 100 can only open and close in the upper flange cava seat 6 and the lower flange cava seat 7 to loosen or lock the pipe column. Regardless of how the force direction of the pipe column changes, the cava tooth plate 9 acts at the same time, and moves against the outer wall of the pipe column to achieve self-locking.

[0071] Even if the axial power slip assembly 100 is accidentally stuck in the pipe column coupling 22 or other positions that do not match the slip tooth plate 9, there is a gap between the slip tooth plate 9 and the outer wall of the pipe column, resulting in insufficient holding force. Fig.10 As shown in the figure, the pipe string slides downward, and when the pipe string coupling 22 slides over the slip tooth plate 9, the axial power slip assembly 100 will be clamped in the position of the pipe string body again, restoring its proper clamping length and achieving the preset clamping force, as shown in the figure. Fig.11 shown.

[0072] In summary, the improved digital two-seat active slip system provided by the utility model can realize the double and two-way clamping function of the slips on the pipe string, and can effectively prevent the pipe string from falling or flying out after losing control. In addition, the slip system can monitor the working status of the slip system in real time through the data acquisition system 200 to realize intelligent control of the slip clamping force.

[0073] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a phase connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0074] The above contents are merely examples and explanations of the structure of the utility model. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the utility model or exceed the scope defined in the claims, they should all fall within the protection scope of the utility model.

Claims

1. An improved digital two-seat active slip system, characterized in that: The slip system comprises an axial power slip assembly (100), a data acquisition system (200), an upper digital flange (300), and a lower digital flange (400); the upper digital flange (300) comprises an upper flange (1) and an upper load sensor (20), and the lower digital flange (400) comprises a lower flange (2) and a lower load sensor (3); the upper load sensor (20) and the lower load sensor (3) are both connected to the data acquisition system (200), so that the data acquisition system (200) can collect operating data of the slip system; the slip system also comprises a guide column (4), two ends of which respectively pass through two ends of the axial power slip assembly (100) and are respectively fixedly connected to the upper flange (1) and the lower flange (2).

2. An improved digital two-seat active slip system according to claim 1, characterized in that: The data acquisition system (200) comprises a data acquisition unit (14), a PLC control unit (15), an on-site control execution unit (16), a display screen (17), an industrial computer (18), and a data center (19).

3. The improved digital two-seat active slip system according to claim 2 is characterized in that: The axial power slip assembly (100) comprises an upper flange slip seat (6), a lower flange slip seat (7), four groups of slip bushings (8), eight groups of slip tooth plates (9), a lubrication groove (10), a buffer pad (11), and a power cylinder (12); every two groups of slip tooth plates (9) are symmetrically installed on the surface of each group of slip bushings (8) in an upper and lower manner; the outer surface of each group of slip bushings (8) is a double cone surface that is symmetrical in an upper and lower manner; the inner surfaces of the upper flange slip seat (6) and the lower flange slip seat (7) are respectively provided with cone surfaces that match the double cone surfaces; the four groups of slip bushings (8) are arranged between the upper flange slip seat (6) and the lower flange slip seat (7); the two ends of the power cylinder (12) are respectively connected to the upper flange slip seat (6) and the lower flange slip seat (7).

4. The improved digital two-seat active slip system according to claim 3 is characterized in that: The guide columns (4) are arranged in four numbers, and the two ends of each guide column (4) respectively pass through the upper flange slip seat (6) and the lower flange slip seat (7) and are respectively fixedly connected to the upper flange (1) and the lower flange (2).

5. The improved digital two-seat active slip system according to claim 3 is characterized in that: The power cylinders (12) are arranged in two groups, and each group of the power cylinders (12) is provided with a hydraulic sensor (13).

6. The improved digital two-seat active slip system according to claim 5 is characterized in that: The data acquisition unit (14) is respectively connected to the upper load sensor (20), the lower load sensor (3), and the hydraulic sensor (13).

7. The improved digital two-seat active slip system according to claim 3 is characterized in that: A spray device (5) is also provided inside the upper flange (1) and inside the lower flange (2), respectively. The spray device (5) is a circular ring structure with a nozzle and is connected to a liquid supply system.

8. The improved digital two-seat active slip system according to claim 3 is characterized in that: A plurality of lubrication grooves (10) are respectively arranged on the outer surface of each group of slip bushings (8), wherein a lubrication strip or lubricant is arranged in each lubrication groove (10).

9. The improved digital two-seat active slip system according to claim 3 is characterized in that: A plurality of groups of buffer pads (11) are respectively arranged on the end surface of each group of slip bushings (8).

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