Adjustable elastic buffering drill rod joint clamping jaw and clamping process thereof

Abstract

The invention provides an adjustable elastic buffering drill rod joint clamping jaw and a clamping process thereof, the clamping jaw is composed of a left part and a right part which are the same in structure and symmetrical to each other, and the left part and the right part move in opposite directions to complete workpiece clamping action; the clamping jaw on one side mainly comprises a main clamp, an auxiliary clamp, a fixing frame, an air cylinder, a connecting disc and the like. One end of the main clamp body is connected with the fixing frame, and the other end is provided with a main clamp structure; the cylinder is connected and fixed with the fixing frame; and the other end of the connecting plate is fixedly connected with the tail end of the robot. The clamping process is realized by adopting the drill rod joint clamping jaw. The clamping jaw has high compatibility, high flexibility and multiple degrees of freedom, can adapt to different feeding processes, is high in grabbing precision, is suitable for stable clamping and flexible feeding of common joints and reducer joints of mining drill rods, and effectively reduces the phenomenon of frequent machine collision caused by poor flexibility of the clamping jaw.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic production of drill pipe machinery, relates to automatic clamping and feeding of drill pipe joints, and specifically relates to an adjustable elastic buffer drill pipe joint clamping claw and a clamping process thereof. Background Art

[0002] In recent years, with the rapid improvement of automation capabilities in the manufacturing industry, articulated robots have been widely used to replace manual repetitive operations. Cylinders are installed at the end of the robot to drive the mechanical gripper to retract to clamp the product. Common grippers have problems such as unstable grasping, single action, limited working space and motion trajectory, especially when the target workstation placement accuracy requirements are high. Due to the limitations of the robot's teaching points and the gripper cylinder stroke, the robot cannot complete the loading if the product's external dimensions are slightly different. Frequent replacement of grippers involves huge waste of time, design and other costs, and existing conventional grippers have great limitations.

[0003] There are many types of mining geological drill pipe joints, and the joint appearance design varies greatly. The size design of the non-threaded clampable part of the joint product has a large range of variation. After the robot gripper grabs the joint, it needs to be placed at the target station of the machine tool according to the predetermined process trajectory. However, due to the small gap between the station hole and the joint, the fault tolerance is low, which easily causes the joint to fall off due to improper placement or unstable center of gravity after the joint is placed. Therefore, the requirements for the gripper to grab the joint are extremely high. If the robot gripper is not compatible with the feeding process trajectory, it will easily lead to frequent collisions with the machine due to poor flexibility of the gripper. Summary of the invention

[0004] In view of the defects and shortcomings of the prior art, the purpose of the present invention is to provide an adjustable elastic buffer drill pipe joint clamp and a clamping process thereof, so as to solve the technical problems in the prior art of poor compatibility of mining drill pipe joint clamps, single action of the robot to execute the end clamp and poor grasping accuracy.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0006] An adjustable elastic buffer drill pipe joint clamp comprises a fixing frame, wherein a cylinder is installed in the fixing frame, and two piston rods of the cylinder can be extended and retracted in the lateral direction, and the two piston rods of the cylinder are respectively connected to a main clamp; the top of the main clamp is movably arranged in the bottom end of the fixing frame, and a secondary clamp is installed on the bottom of the main clamp.

[0007] The main clamp comprises a main clamp body, which is a long plate-shaped structure. The top of the main clamp body is movably arranged in the bottom end of the fixed frame. A floating clamp block is movably nested on the lateral inner side of the bottom of the main clamp body. The inner side of the floating clamp block is an arc surface and contacts the workpiece. A limit block is fixedly installed on the lateral outer side of the bottom of the main clamp body. A buffer is installed on the limit block through a thread. The buffer is arranged along the lateral direction. The inner end of the buffer is a compression end. The inner end of the buffer passes through the limit block and the main clamp body in turn and contacts the floating clamp block. Adjustment bolts are respectively arranged on the upper and lower sides of the buffer. The adjustment bolts are arranged along the lateral direction. The lateral outer end of the adjustment bolt is installed on the main clamp body, and the lateral inner end of the adjustment bolt is connected to the floating clamp block. When the adjustment bolt is turned, the floating clamp block and the buffer are extended and retracted accordingly.

[0008] The auxiliary clamp includes a straightening jaw, which is arranged parallel to the main clamp body, and one longitudinal end of the guide rod is fixedly mounted on the straightening jaw, and the other longitudinal end of the guide rod is mounted on the main clamp body; a compressor is provided on the outer sleeve of the guide rod, and the longitudinal ends of the compressor are respectively in close contact with the straightening jaw and the main clamp body; a pair of sliding devices are provided on the lateral inner side of the straightening jaw, and the rollers on the inner side of the sliding devices are in contact with the workpiece.

[0009] The present invention also has the following technical features:

[0010] The compressor is equipped with a built-in signal feedback device.

[0011] The surface of the straightening clamping jaw is provided with a buffer pad.

[0012] The buffer pad is made of rubber, silica gel or polyurethane.

[0013] A connecting plate is installed on the top of the fixing frame.

[0014] The number of the buffer installed on a single main clamp body is at least one; the number of the adjusting bolts installed on a single main clamp body is at least two.

[0015] The number of the sliding devices installed on a single righting clamping jaw is at least two.

[0016] The present invention also protects a process for clamping a drill pipe joint with an adjustable elastic buffering jaw, which is implemented by using the adjustable elastic buffering drill pipe joint jaw as described above; the process includes: adjusting the jaw to fit the workpiece and fixing it, and after testing the feedback device to be normal, the robot clamps the workpiece and moves it along the path to the workstation orifice; when the auxiliary clamp contacts the end face of the workstation, the coordinates are detected, and if the deviation is ≥0.5mm, adjustment is required; when the front end face of the auxiliary clamp's straightening jaw contacts the end face of the machine tool and is in a non-compressed state, L 1 is the maximum displacement that the compressor can compress, L 2is the distance from the end face of the workpiece to the bottom of the station hole at this state, that is, the advancing distance of the workpiece; when L 1 ≥L 2 continuously advance until the joint touches the bottom, and record the pressure signal a 1 ; when L 1 <L 2 it is necessary to compress the buffer to the limit and then release the jaw to reposition until it touches the bottom and record the signal a 2 ; finally, complete the feeding process through signal feedback.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects:

[0018] (Ⅰ) The jaw of the present invention is designed with a main jaw and a sub-jaw. The main jaw is provided with a floating jaw and a buffer device, which can be compatible with joints of different outer diameters to the greatest extent. At the same time, after grasping the joint, the buffer device is squeezed to continuously clamp the outer wall of the joint, increasing the stability of grasping, preventing shaking caused by gravity or product processing differences, and ensuring the accuracy of the process trajectory.

[0019] (Ⅱ) In order to make up for the defects of the robot's motion trajectory, the present invention sets a compressible sub-jaw at the front end of the main jaw, and the sub-jaw realizes the functions of straightening and guiding, extending the protection range of the jaw.

[0020] (Ⅲ) The design of the present invention improves the flexibility of the robot jaw. The buffer device set on the main jaw increases the radial movement of the jaw, enhancing the earthquake resistance during the movement; the compressible sub-jaw connected to the front end of the main jaw increases the axial movement of the jaw, making up for the limitations of the preset process path.

[0021] (Ⅳ) In summary, the jaw of the present invention has high compatibility, high flexibility and multiple degrees of freedom, can adapt to different feeding processes, has high grasping accuracy, is suitable for stable grasping and flexible feeding of ordinary joints and variable-diameter joints of mining drill pipes, and effectively reduces the phenomenon of frequent collisions caused by poor flexibility of the jaw. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the overall structural schematic diagram of the adjustable elastic buffer drill pipe joint jaw.

[0023] Figure 2 is the structural schematic diagram of the main jaw and the sub-jaw.

[0024] Figure 3 is the working process schematic diagram of the adjustable elastic buffer drill pipe joint jaw.

[0025] The meanings of the various reference numerals in the figure are: 1 - fixed frame, 2 - cylinder, 3 - main jaw, 4 - sub-jaw, 5 - connecting plate, 6 - workpiece, 7 - machine tool.

[0026] 301 - Main clamp body, 302 - Floating clamp block, 303 - Limit block, 304 - Buffer, 305 - Adjusting bolt.

[0027] 401 - Centering jaw, 402 - Compressor, 403 - Sliding device, 404 - Buffer pad.

[0028] The technical solution of the present invention will be further described below in conjunction with embodiments. Specific embodiments

[0029] It should be noted that all the components and devices used in the present invention, without special instructions, are all components and devices known in the art. For example: the buffer 304 uses a conventional buffer known in the prior art.

[0030] Complying with the above technical solution, the following specific embodiments of the present invention are given. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent transformations made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0031] Embodiment 1:

[0032] This embodiment provides an adjustable elastic buffer drill pipe joint jaw, which is composed of two identical and symmetric left and right parts. The left and right parts move towards each other to complete the workpiece clamping action; one-sided jaws mainly include a main clamp, a sub-clamp, a fixed frame, a cylinder, a connecting plate, etc.; one end of the main clamp body is connected to the fixed frame, and the other end is provided with a main clamp structure; the cylinder is connected and fixed to the fixed frame; one end of the connecting plate is connected to the fixed frame, and the other end is connected and fixed to the end of the robot.

[0033] As Figure 1 shown, a cylinder 2 is installed in the fixed frame 1. The two piston rods of the cylinder 2 can stretch along the horizontal direction. The two piston rods of the cylinder 2 are respectively connected to a main clamp 3; the top of the main clamp 3 is movably arranged inside the bottom end of the fixed frame 1, and a sub-clamp 4 is installed on the bottom of the main clamp 3.

[0034] As Figure 2As shown, the main clamp 3 includes a main clamp body 301, which is a long strip-shaped structure. The top of the main clamp body 301 is movably arranged in the bottom end of the fixed frame 1, and a floating clamp block 302 is movably nested on the lateral inner side of the bottom of the main clamp body 301. The inner side of the floating clamp block 302 is an arc surface and contacts the workpiece 6; a limit block 303 is fixedly installed on the lateral outer side of the bottom of the main clamp body 301, and a buffer 304 is installed on the limit block 303 through a thread. The buffer 304 is arranged along the lateral direction. The inner end of the device 304 is the compression end, and the inner end of the buffer 304 passes through the limit block 303 and the main clamp body 301 in sequence and contacts the floating clamp block 302; the upper and lower sides of the buffer 304 are respectively provided with adjusting bolts 305, and the adjusting bolts 305 are arranged along the horizontal direction. The horizontal outer end of the adjusting bolt 305 is installed on the main clamp body 301, and the horizontal inner end of the adjusting bolt 305 is connected to the floating clamp block 302; when the adjusting bolt 305 is turned, the floating clamp block 302 and the buffer 304 are extended and retracted accordingly.

[0035] like Figure 2 As shown, the auxiliary clamp 4 includes a straightening jaw 401, which is arranged parallel to the main clamp body 301, and one longitudinal end of the guide rod is fixedly mounted on the straightening jaw 401, and the other longitudinal end of the guide rod is mounted on the main clamp body 301; a compressor 402 is provided on the outer sleeve of the guide rod, and the longitudinal ends of the compressor 402 are respectively in close contact with the straightening jaw 401 and the main clamp body 301; a pair of sliding devices 403 are provided on the lateral inner side of the straightening jaw 401, and the rollers on the inner side of the sliding device 403 are in contact with the workpiece 6.

[0036] In this embodiment, the workpiece 6 includes a common drill pipe joint, a drill pipe reducer joint, etc. The main clamp 3 is responsible for clamping the welding end of the workpiece 6. By adjusting the limit position of the adjusting bolt 305 and the telescopic degree of the buffer 304, the fitting degree between the floating clamp block 302 and the workpiece 6 is adjusted to achieve compatible clamping of workpieces 6 with different outer diameters. The auxiliary clamp 4 is responsible for straightening the workpiece 6 to prevent the workpiece 6 from tilting and escaping from the clamp due to gravity or centrifugal force during movement. At the same time, the compressible function of the auxiliary clamp 4 improves the gripping flexibility of the clamp.

[0037] As a specific solution of this embodiment, the compressor 402 includes an outer shell, and a compression spring and a signal feedback device are arranged in the outer shell of the compressor 402. In this embodiment, the compressor 402 is a general device in the control system for transmitting output (such as displacement, speed, temperature, pressure, etc.) back to the controller in real time, wherein the displacement sensor serves as the core of the signal feedback device.

[0038] As a specific solution of this embodiment, the sliding device 403 includes a roller shaft, and the roller shaft outer shell is provided with an inner roller and an outer roller. In this embodiment, the outer roller directly contacts the surface of the workpiece 6, and the rolling friction replaces the sliding friction to reduce the contact surface resistance coefficient.

[0039] As a specific solution of this embodiment, Figure 2 As shown, a buffer pad 404 is provided on the surface of the straightening jaw 401. In this embodiment, the buffer pad 404 is usually made of an elastic material (such as rubber, silicone or polyurethane), which can avoid direct hard contact between the straightening jaw 401 and the workpiece 6, and prevent scratches, indentations or deformation. The high friction coefficient of the buffer pad 404 can increase the clamping stability and prevent the workpiece 6 from sliding or falling off during transportation or positioning. The buffer pad 404 can absorb the impact force when the straightening jaw 401 is closed or moved, reduce the damage to the object and the jaw caused by mechanical vibration, and improve the positioning accuracy (for example, avoiding deviation caused by vibration in a high-speed automated production line). The buffer pad 404 reduces the hard friction between the jaw and the object, reduces the wear and fatigue of the jaw itself, and at the same time, the buffer pad 404 itself is easy to replace, and the maintenance cost is lower than replacing the entire jaw.

[0040] As a specific solution of this embodiment, Figure 1 As shown, a connection plate 5 is installed on the top of the fixing frame 1, and the top of the connection plate 5 is connected to the end of the robot. In this embodiment, the connection plate 5 provides a solid physical interface to ensure that the gripper is firmly installed to withstand the force, torque and vibration during operation.

[0041] As a specific solution of this embodiment, the compression direction of the buffer 304 is consistent with the movement direction of the cylinder 2, the number of buffers 304 installed on a single main clamp body 301 is at least one; the number of adjusting bolts 305 installed on a single main clamp body 301 is at least two; the number of sliding devices 403 installed on a single straightening clamp 401 is at least two.

[0042] Embodiment 2:

[0043] This embodiment provides a process for clamping a drill pipe joint with an adjustable elastic buffering jaw, which is implemented by using the adjustable elastic buffering drill pipe joint jaw of Embodiment 1; the process specifically includes the following steps:

[0044] Step 1: Place the workpiece 6 between the adjustable elastic buffer drill pipe joint jaws, and retract the cylinder 2 until the main clamp 3 and the sub-clamp 4 contact the surface of the workpiece 6; adjust the welding end face of the workpiece 6 to be flush with the bottom of the jaws, and adjust the adjusting bolts 305 of the two parts of the main clamp 3 on the left and right to make the floating clamp block 302 fully fit the surface of the workpiece 6, and keep the axes of the main clamp 3 and the sub-clamp 4 consistent. At this time, tighten the adjusting bolts 305; adjust the positions of the buffers 304 of the two parts of the main clamp 3 on the left and right so that the compression ends of the buffers 304 contact the floating clamp block 302 and keep the free state.

[0045] Step 2: Manually press the sub-clamp 4 to make it close to the main clamp 3, and squeeze the compressor 402 to test whether the built-in signal feedback device works properly.

[0046] Step 3: The robot grips the workpiece 6 through the elastic buffer jaws and moves it to the orifice of the working station along the predetermined process path, keeping the axis of the workpiece 6 coincident with the axis of the working station hole; during the movement, the buffer 304 of the main clamp 3 always supports the floating clamp block 302 to prevent the workpiece 6 from shaking violently.

[0047] Step 4: The workpiece 6 moves slowly along the axis of the working station hole towards the working station until the two sub-clamps 4 on the left and right contact the end face of the working station at the same time. At this time, the compressor 402 is in the free state, triggering the built-in feedback devices of the two compressors 402, and marking the spatial coordinates of the left clamp here as X 1 , Y 1 , Z 1 , and the spatial coordinates of the right clamp are X 2 , Y 2 , Z 2 ; If the two compressors 402 on the left and right are not triggered simultaneously, and |X 1 - X 2 | ≥ 0.5 mm or |Z 1 - Z 2 | ≥ 0.5 mm, it is necessary to check whether the buffer jaws are parallel to the end face of the working station, and repeat the above actions again after adjusting the posture.

[0048] As Figure 3 shown, when the front end face of the centering jaw 401 of the sub-clamp 4 contacts the end face of the machine tool 7 and is in the uncompressed state, L 1 is the maximum compressible displacement of the compressor 402, and L 2 is the distance from the end face of the workpiece 6 to the bottom of the working station hole in this state, that is, the advancing distance of the workpiece 6.

[0049] Step 5: When L 1 ≥ L 2When this happens, the specific process is as follows: The workpiece 6 continues to move slowly along the axis of the station hole towards the station. At this time, the compressor 402 is gradually compressed, and the pressure also gradually increases until the front end face of the workpiece 6 contacts the bottom of the station hole and reaches the predetermined process position. At this time, the electrical signal corresponding to the pressure of the compressor 402 is a 1 , and communication is completed with the control box through the signal feedback device and recorded.

[0050] Step six, after grasping the subsequent workpiece 6 and completing step four, when the compressor 402 is gradually compressed until the electrical signal is a 1 At this time, the front end face of the workpiece 6 contacts the bottom of the station hole and reaches the predetermined process position. The control box communicates with the signal feedback device, and this feeding process is completed.

[0051] As a specific solution of this embodiment, a central control system is used to be responsible for motion data acquisition and display, coordinate data processing and communication of the workpiece 6. When the central control system performs data processing, the central control system reads data through the RS232 communication bus with the LS 9030 to obtain the coordinate data of the clamped workpiece 6, and is responsible for calculating through the measured data and the calibrated data to obtain the measured data of the workpiece 6. The central control system performs data interaction with the PLC controller through OPC and is responsible for monitoring the states of the clamping cylinder 2, the compressor 402, and the jaws of the workpiece 6.

[0052] Embodiment 3:

[0053] This embodiment provides an adjustable elastic buffer drill pipe joint jaw clamping process, which is implemented by using the adjustable elastic buffer drill pipe joint jaw of Embodiment 1. In this embodiment, steps one to four of this process are exactly the same as steps one to four of Embodiment 2. The main difference from Embodiment 2 is that steps five and six are different.

[0054] Step five, when L 1 < L 2 When this happens, the specific process is as follows:

[0055] The workpiece 6 continues to move slowly along the axis of the station hole towards the station. At this time, the compressor 402 is gradually compressed, and the pressure also gradually increases until the compressor 402 is compressed to the limit shortest length. At this time, the cylinder 2 drives the jaws to open, moves in the opposite direction until the end face of the sub-jaw 4 is separated from the workpiece 6, the jaws close, the jaws move along the axis of the station hole towards the station direction to contact the end face of the workpiece 6, and continue to move forward to push the workpiece 6. The compressor 402 is gradually compressed until the front end face of the workpiece 6 contacts the bottom of the station hole and reaches the predetermined process position. At this time, the electrical signal corresponding to the pressure of the compressor 402 is a 2 , and communication is completed with the control box through the signal feedback device and recorded.

[0056] Step 6: After grasping the subsequent workpiece 6 and completing Step 4, the gripper closes. The gripper moves along the axis of the station hole towards the station direction until it contacts the end face of the workpiece 6, and then continues to move forward to push the workpiece 6, and the compressor 402 is gradually compressed. When the compressor 402 is gradually compressed until the electrical signal is a 2 At this time, the front end face of the workpiece 6 contacts the bottom of the station hole, reaching the predetermined process position. The control box communicates with the signal feedback device, and this feeding process is completed.

Claims

1. An adjustable elastic buffer drill pipe joint clamp, comprising a fixing frame (1), characterized in that: The fixing frame (1) is provided with a cylinder (2), the two piston rods of the cylinder (2) are capable of extending and retracting in a lateral direction, and the two piston rods of the cylinder (2) are respectively connected to a main clamp (3); the top of the main clamp (3) is movably arranged in the bottom end of the fixing frame (1), and a secondary clamp (4) is installed on the bottom of the main clamp (3); The main clamp (3) comprises a main clamp body (301), which is a long strip-shaped structure. The top of the main clamp body (301) is movably arranged in the bottom end of the fixed frame (1). A floating clamp block (302) is movably nested on the lateral inner side of the bottom of the main clamp body (301). The inner side of the floating clamp block (302) is a circular arc surface and contacts the workpiece (6). A limit block (303) is fixedly installed on the lateral outer side of the bottom of the main clamp body (301). A buffer (304) is installed on the limit block (303) through a thread. The buffer (304) is arranged along the lateral direction. The inner end of the buffer (304) is a compression end. The inner end of the buffer (304) sequentially passes through the limit block (303) and the main clamp body (301) and contacts the floating clamp block (302). The upper and lower sides of the buffer (304) are respectively provided with adjustment bolts (305). The adjustment bolts (305) are arranged along the transverse direction. The transverse outer end of the adjustment bolt (305) is installed on the main clamp body (301), and the transverse inner end of the adjustment bolt (305) is connected to the floating clamp block (302). When the adjustment bolt (305) is turned, the floating clamp block (302) and the buffer (304) are extended and retracted accordingly. The auxiliary clamp (4) comprises a straightening clamp (401), which is arranged parallel to the main clamp body (301), and one longitudinal end of a guide rod is fixedly mounted on the straightening clamp (401), and the other longitudinal end of the guide rod is mounted on the main clamp body (301); a compressor (402) is arranged on the outer sleeve of the guide rod, and the longitudinal ends of the compressor (402) are respectively in close contact with the straightening clamp (401) and the main clamp body (301); a pair of sliding devices (403) are arranged on the lateral inner side of the straightening clamp (401), and the rollers on the inner side of the sliding devices (403) are in contact with the workpiece (6).

2. The adjustable elastic buffer drill pipe joint clamping jaw according to claim 1, characterized in that: The compressor (402) has a built-in signal feedback device.

3. The adjustable elastic buffer drill pipe joint clamping jaw according to claim 1, characterized in that: A buffer pad (404) is provided on the surface of the straightening clamping jaw (401).

4. The adjustable elastic buffer drill pipe joint clamping jaw according to claim 2, characterized in that: The buffer pad (404) is made of rubber, silicone or polyurethane.

5. The adjustable elastic buffer drill pipe joint clamping jaw according to claim 1, characterized in that: A connecting plate (5) is installed on the top of the fixing frame (1).

6. The adjustable elastic buffer drill pipe joint clamping jaw according to claim 1, characterized in that: The number of the buffer (304) installed on a single main clamp body (301) is at least one; the number of the adjusting bolts (305) installed on a single main clamp body (301) is at least two.

7. The adjustable elastic buffer drill pipe joint clamping jaw according to claim 1, characterized in that: The number of the sliding devices (403) installed on a single straightening clamp (401) is at least two.

8. A process for clamping a drill pipe joint with an adjustable elastic buffer jaw, characterized in that: The process is implemented by using the adjustable elastic buffer drill pipe joint clamping jaw as described in any one of claims 1 to 7; the process comprises: The clamping jaws are adjusted to fit the workpiece (6) and then fixed. After the test feedback device is normal, the robot clamps the workpiece (6) and moves along the path to the workstation opening; when the auxiliary clamp (4) contacts the end face of the workstation, the coordinates are detected, and if the deviation is ≥0.5mm, adjustment is required; When the front end face of the straightening clamping jaw (401) of the auxiliary clamp (4) contacts the end face of the machine tool (7) and is in a non-compressed state, L1 is the maximum compressible displacement of the compressor (402), and L2 is the distance from the end face of the workpiece (6) to the bottom of the workstation hole in this state, that is, the advancement distance of the workpiece (6); when L1≥L2, the joint is continuously advanced until it touches the bottom, and the pressure signal a1 is recorded; when L1<L2, the buffer needs to be compressed to the limit and then the clamping jaw is released and repositioned until it touches the bottom and the signal a2 is recorded; finally, the material discharge process is completed through signal feedback.

9. The adjustable elastic buffer drill pipe joint clamping process as claimed in claim 8, characterized in that: The process specifically includes the following steps: Step 1: Place the workpiece (6) between the adjustable elastic buffer drill pipe joint jaws, shrink the cylinder (2) until the main clamp (3) and the auxiliary clamp (4) are in contact with the surface of the workpiece (6); adjust the welding end face of the workpiece (6) to be flush with the bottom of the clamp, adjust the adjustment bolts (305) of the left and right main clamps (3) to make the floating clamp (302) completely fit with the surface of the workpiece (6), and keep the axes of the main clamp (3) and the auxiliary clamp (4) consistent, and then tighten the adjustment bolts (305); adjust the positions of the buffers (304) of the left and right main clamps (3) to make the compression end of the buffer (304) contact with the floating clamp (302) and maintain a free state; Step 2: manually press the auxiliary clamp (4) to bring it close to the main clamp (3), and squeeze the compressor (402) to test whether the built-in signal feedback device works normally; Step 3: clamp the workpiece (6) with the elastic buffer clamping jaws and move it to the opening of the workstation according to the predetermined process path, so that the axis of the workpiece (6) and the axis of the workstation hole remain coincident; during the movement, the buffer (304) of the main clamp (3) always supports the floating clamping block (302) to prevent the workpiece (6) from shaking violently; Step 4: The workpiece (6) moves slowly toward the workstation along the axis of the workstation hole until the left and right side auxiliary clamps (4) contact the workstation end face at the same time. At this time, the compressor (402) is in a free state, triggering the built-in feedback devices of the compressors (402) on both sides, and marking the spatial coordinates of the left clamp as (X1, Y1, Z1) and the spatial coordinates of the right clamp as (X2, Y2, Z2); if the left and right side compressors (402) are not triggered at the same time, and |X1-X2|≥0.5mm or |Z1-Z2|≥0.5mm, it is necessary to check whether the buffer clamp is parallel to the workstation end face, adjust the posture and repeat the above action again; Step 5, when L1≥L2, the specific process is as follows: the workpiece (6) continues to move slowly toward the workstation along the axis of the workstation hole, at which time the compressor (402) is gradually compressed and the pressure gradually increases until the front end surface of the workpiece (6) contacts the bottom of the workstation hole and reaches the predetermined process position; at this time, the electrical signal corresponding to the pressure of the compressor (402) is a1, which is communicated and recorded with the control box through the signal feedback device; Step six, grab the subsequent workpiece (6) after completing step four, when the compressor (402) is gradually compressed to the electrical signal a1, the front end surface of the workpiece (6) contacts the bottom of the workstation hole and reaches the predetermined process position, the control box communicates with the signal feedback device, and the discharge process is completed.

10. The adjustable elastic buffer drill pipe joint clamping process according to claim 9, characterized in that: When L1<L2, step five is specifically as follows: the workpiece (6) continues to move slowly toward the workstation along the axis of the workstation hole, at which time the compressor (402) is gradually compressed, and the pressure is gradually increased until the compressor (402) is compressed to the shortest limit length; at this time, the cylinder (2) drives the clamping jaws to open, and moves in the opposite direction until the end face of the auxiliary clamp (4) is separated from the workpiece (6), the clamping jaws are closed, and the clamping jaws move along the axis of the workstation hole toward the workstation direction until they contact the end face of the workpiece (6), and continue to move forward to push the workpiece (6), and the compressor (402) is gradually compressed until the front end face of the workpiece (6) contacts the bottom of the workstation hole and reaches the predetermined process position; at this time, the electrical signal corresponding to the pressure of the compressor (402) is a2, which is communicated and recorded with the control box through the signal feedback device; Step six is ​​as follows: After the subsequent workpiece (6) is grabbed and step four is completed, the clamp is closed, and the clamp moves along the axis of the workstation hole toward the workstation direction until it contacts the end face of the workpiece (6), and continues to move forward to push the workpiece (6). The compressor (402) is gradually compressed. When the compressor (402) is gradually compressed to the electrical signal a2, the front end face of the workpiece (6) contacts the bottom of the workstation hole and reaches the predetermined process position. The control box communicates with the signal feedback device, and the material discharge process is completed.

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