Ironworker clamping force self-adaptive control system and control method thereof

Abstract

The present application iron roughneck clamping force self-adaptive control system, including hydraulic control system and electrical control system two subsystems, hydraulic control system is mainly composed of lower jaw, clamping force sensor, upper jaw, lower jaw control valve, upper jaw control valve, clamping force control valve, torque control valve, impact cylinder control valve, torque sensor, impact cylinder, shuttle valve a and shuttle valve b; electrical control system is composed of operation unit, PLC controller, remote control relay, proportional amplifier and the like. The system records and analyzes the past upper and lower drilling tool data, automatically matches the best clamping force for different drilling tools, and automatically adapts to the change of the clamping force during the upper and lower make-up and break-out of the drilling tool. The problem of the drilling tool being clamped, the success rate of the drilling tool being made up and broken out being reduced, the clamping jaw mechanism being worn, the jaw being consumed at a faster speed, and the equipment maintenance cost being increased is solved.

Description

Technical Field

[0001] This invention belongs to the field of petroleum machinery and equipment technology, specifically relating to an adaptive control system for clamping force of a steel drill, and also to a control method for the above-mentioned control system. Background Technology

[0002] In iron drill operations, the matching between clamping force and the torque for attaching and unattaching directly determines the degree of damage to the drill bit, the lifespan of its own components, and the efficiency of attaching and unattaching operations. Currently, the clamping force setting for iron drills both domestically and internationally generally adopts the following two methods: 1) Designed based on the maximum clamping force; 2) Designed with several clamping force levels, with manual or hydraulic automatic selection of different levels depending on the drill bit. The second approach is an improvement on the first, but neither can achieve optimal torque for attaching and unattaching and optimal clamping force for different drill bits. Common problems include: 1) Small drill bits being clamped by a large clamping force, resulting in damage to the drill bit; 2) Insufficient clamping force causing slippage between the jaws and the drill bit; 3) Prolonged clamping with a large clamping force increases wear on the clamping mechanism, accelerates jaw wear, and increases equipment maintenance costs. Summary of the Invention

[0003] The purpose of this invention is to provide an adaptive clamping force control system for iron drill bits. This system can automatically match the optimal clamping force for different drill bits, and the clamping force automatically adapts to the changes in the clamping and unclamping torque during the drilling and unclamping process.

[0004] Another object of the present invention is to provide a control method for the above-described control system.

[0005] The technical solution adopted in this invention is as follows: the adaptive clamping force control system for iron drills includes a hydraulic control system and an electrical control system, both controlled by the same PLC controller. The input terminals of the PLC controller are connected to an operating unit, a clamping force sensor, and a torque sensor. The output terminals of the PLC controller are connected to a remote control relay and a proportional amplifier. The remote control relay is connected to the control solenoids on the lower clamp control valve, the upper clamp control valve, and the punch cylinder control valve. The proportional amplifier is connected to the control solenoids on the clamping force control valve and the torque control valve. The lower clamp control valve is connected to the lower clamp, and the clamping force sensor is installed on the connecting pipeline between the lower clamp control valve and the lower clamp cylinder piston chamber. The upper clamp control valve is connected to the upper clamp. The upper clamp control valve and the lower clamp control valve are connected to the clamping force control valve. The rod-side and rodless-side chambers of the punch cylinder are respectively connected to the two inlets of shuttle valve a. The outlet of shuttle valve a is then connected to a torque sensor. The two load signal external interfaces of the punch cylinder control valve are led out and connected to the two inlets of shuttle valve b. The outlet of shuttle valve b is then connected to the torque control valve.

[0006] The invention is further characterized by:

[0007] Each of the upper clamp control valve and the lower clamp control valve has a check valve connected to its load signal external interface. The two check valves merge and then connect to the clamping force control valve.

[0008] The lower clamp control valve, upper clamp control valve, and punch cylinder control valve are all load-sensitive electro-hydraulic multi-way valves with external load signal interfaces. The working port of the lower clamp control valve is connected to the lower clamp cylinder, the working port of the upper clamp control valve is connected to the upper clamp cylinder, and the working port of the punch cylinder control valve is connected to the rod chamber and rodless chamber of the punch cylinder.

[0009] Both the clamping force control valve and the torque control valve are proportional electromagnetic relief valves.

[0010] Another technical solution adopted in this invention is the control method of the iron drill clamping force adaptive control system, which includes an upper clamping operation control method and an unclamping operation control method. The upper clamping operation control method specifically includes the following steps:

[0011] Step 1: Select the drill string model to be processed and set the target value of the top clamping torque. After this information is input into the PLC controller, the PLC controller outputs a control signal to the proportional amplifier corresponding to the clamping force control valve 6 based on the preset clamping force value data of the drill string model during the swivel operation. After the signal is amplified by the proportional amplifier, it controls and adjusts the proportional electromagnet of the clamping force control valve 6, and then sets the clamping force of the lower clamp 1 during swivel. Then, the remote control relay drives the lower clamp control valve 4 to achieve clamping of the lower clamp 1, and the swivel clamp starts the swivel operation. After 5 to 10 seconds of swivel, the swivel is completed.

[0012] Step 2: The PLC controller outputs a control signal to the proportional amplifier corresponding to the torque control valve 7 based on the target torque value of the drill bit selected in Step 1. After the signal is amplified by the proportional amplifier, it controls the proportional solenoid of the torque control valve 7. The proportional solenoid adjusts the set value of the torque control valve 7, thereby setting the initial torque value of the punch cylinder 10. The clamping force control valve 6 is adjusted to set the initial clamping force values ​​of the upper clamp 3 and the lower clamp 1. The PLC controller outputs a control signal to the remote control relays corresponding to the lower clamp control valve 4 and the upper clamp control valve 5, controlling the solenoids of the lower clamp control valve 4 and the upper clamp control valve 5 to realize the switching of these two valves, supplying oil to the lower clamp 1 and the upper clamp 3 to realize the clamping of the upper and lower clamps, and completing the preparation work for the drill bit to make the trip.

[0013] Step 3: When the upper clamping operation begins, the PLC controller outputs a control signal to the remote control relay corresponding to the clamping cylinder control valve 8, controlling the electromagnet of the clamping cylinder control valve 8 to switch the valve and supply liquid to the clamping cylinder 10 to achieve the upper clamping action. The torque sensor 9 collects the real-time torque of the clamping cylinder 10 and transmits it to the PLC controller. According to the torque change of the clamping cylinder 10, the PLC controller outputs a control signal to the proportional amplifier corresponding to the clamping force control valve 6 in real time, controlling the clamping force control valve 6 to adjust the clamping force of the lower clamp 1 and the upper clamp 3 in real time, so that the clamping force changes synchronously with the torque change of the clamping cylinder 10. At the same time, the clamping force sensor 2 monitors the changes in the clamping force of the lower clamp 1 and the upper clamp 3 and transmits them to the PLC controller.

[0014] Step 4: When the final torque value in step 3 reaches the upper clamping torque target value, the upper clamping action is completed. If the final torque value does not reach the upper clamping torque target value, the upper clamp 3 is released and reset, and steps 2 and 3 are repeated until the final torque value reaches the upper clamping torque target value.

[0015] Step 5: After the upper clamping action is completed, the upper clamp 3 and lower clamp 1 are released and reset. The system will create an array and number it for the drill pipe. The final value of the clamping force of the upper clamp 3 and lower clamp 1 fed back by the clamping force sensor 2 and the final value of the torque of the punching cylinder 10 monitored by the torque sensor 9 will be recorded in the array. This array will be used for the system's machine learning to optimize the initial value of the clamping force of the upper clamp 3 and lower clamp 1 for the next upper and lower clamping operation.

[0016] The specific steps of the uncoupling operation control method include:

[0017] Step 1: Select the drill string model to be processed. The PLC controller generates the initial torque value of the punch cylinder 10 and the initial clamping force values ​​of the lower tongs 1 and upper tongs 3 for this uncoupling operation based on the final values ​​of the clamping force of the upper tongs 3 and lower tongs 1 and the final torque value of the punch cylinder 10 recorded during the upper tongs operation of the drill string with this number.

[0018] Step 2: Based on the initial torque and clamping force values ​​in Step 1, the PLC controller outputs control signals to the proportional amplifiers corresponding to the torque control valve 7 and clamping force control valve 6. After the signals are amplified by the proportional amplifiers, the torque control valve 7 and clamping force control valve 6 are controlled to achieve the initial value setting of the unhooking torque and clamping force. Then, the system controls the lower clamp control valve 4 and the upper clamp control valve 5 to achieve upper and lower clamping, completing the preparation work for the iron drill unhooking.

[0019] Step 3: After the uncoupling operation begins, the system controls the reversing of the control valve 8 of the punching cylinder to inject oil into the plug chamber of the punching cylinder 10 to achieve the uncoupling action. When there is a relative displacement between the upper clamp 3 and the lower clamp 1, the uncoupling is successful. If the uncoupling is unsuccessful, the new torque value and clamping force value are reset according to 1.3 times the original initial torque value and clamping force value. The PLC controller outputs the control signal to the proportional amplifier corresponding to the torque control valve 7 and the clamping force control valve 6. After the signal is amplified by the proportional amplifier, the torque control valve 7 and the clamping force control valve 6 are controlled to modify the initial values ​​of the uncoupling torque and clamping force. Then the uncoupling process is entered again. If the uncoupling is successful, the system controls the upper clamp 3 to release, the lower clamp 1 to continue clamping, and the twisting pliers to start twisting. After the twisting is completed, the twisting pliers release, the lower clamp 1 releases, and the uncoupling operation is completed.

[0020] Step 4: After the unhooking is completed, the system records the final values ​​of the clamping forces of the upper clamp 3 and lower clamp 1 recorded by the clamping force sensor 2 and the final value of the torque of the punch cylinder 10 monitored by the torque sensor 9 to the database. This data is used for system machine learning and optimization of the initial values ​​of the clamping forces of the upper clamp 3 and lower clamp 1 and the initial value of the torque of the punch cylinder 10 for the next unhooking operation.

[0021] Another feature of the technical solution of the present invention is that:

[0022] The principle of the clamping force value changing with the torque value in the upper clamping operation control method is as follows: the correspondence between the upper clamping torque value and the clamping force value at the critical slippage of this type of drill bit is measured. During the upper clamping process, according to this correspondence, the clamping force value becomes 1.2 to 1.5 times the critical slippage clamping force value corresponding to the torque value.

[0023] The beneficial effects of this invention are: The adaptive clamping force control system for iron drills solves the problems caused by the mismatch between the torque and clamping force during the engagement and disengagement of different drill tools in existing domestic and international solutions. These problems lead to drill tool damage, slippage, increased wear on the clamping mechanism, accelerated wear of the clamping teeth, and increased equipment maintenance costs. This invention's control system is simple and easy to operate, significantly reducing wear on equipment and drill tools during engagement and disengagement. Attached Figure Description

[0024] Figure 1 This is a hydraulic schematic diagram of the adaptive clamping force control system for iron drillers of the present invention;

[0025] Figure 2 This is a flowchart of the upper clamping process of the adaptive clamping force control system for iron drillers of the present invention;

[0026] Figure 3 This is a flowchart of the unhooking process of the adaptive control system for clamping force of the iron driller according to the present invention.

[0027] Among them: 1. Lower clamp, 2. Clamping force sensor, 3. Upper clamp, 4. Lower clamp control valve, 5. Upper clamp control valve, 6. Clamping force control valve, 7. Torque control valve, 8. Punch cylinder control valve, 9. Torque sensor, 10. Punch cylinder, 11. Shuttle valve a, 12. Shuttle valve b. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0029] This invention relates to an adaptive clamping force control system for iron drills, comprising a hydraulic control system and an electrical control system, both controlled by the same PLC controller. The principle of the hydraulic control system is as follows: Figure 1 As shown, it includes a lower clamp 1, a clamping force sensor 2, an upper clamp 3, a lower clamp control valve 4, an upper clamp control valve 5, a clamping force control valve 6, a torque control valve 7, a punch cylinder control valve 8, a torque sensor 9, a punch cylinder 10, a shuttle valve a 11, and a shuttle valve b 12; the electrical control system includes an operating unit, a PLC controller, a remote control relay, and a proportional amplifier.

[0030] The input terminals of the PLC controller are connected to the operation unit, clamping force sensor 2, and torque sensor 9. The output terminals of the PLC controller are connected to the remote control relay and the proportional amplifier. The remote control relay is connected to the control solenoids on the lower clamp control valve 4, the upper clamp control valve 5, and the punch cylinder control valve 8. The proportional amplifier is connected to the control solenoids on the clamping force control valve 6 and the torque control valve 7.

[0031] The lower clamp control valve 4 is connected to the lower clamp 1, and the clamping force sensor 2 is installed on the connecting pipeline between the lower clamp control valve 4 and the cylinder chamber of the lower clamp 1; the upper clamp control valve 5 is connected to the upper clamp 3.

[0032] The load signal external interfaces of the upper clamp control valve 5 and the lower clamp control valve 4 are each connected to a check valve, and then they are combined into one line. After the line is combined, it is connected to the clamping force control valve 6. During operation, the check valve installed on the valve with the higher pressure will open to conduct pressure oil to the clamping force control valve 6, thereby regulating the clamping force. The valve with the lower pressure will be blocked.

[0033] The rod-side and rodless chambers of the snap-fit ​​cylinder 10 are connected to the two inlets of shuttle valve a 11, respectively. The outlet of shuttle valve a 11 is then connected to torque sensor 9, allowing a single torque sensor to monitor both the snap-fit ​​torque and the unsnap torque. The two load signal interfaces of the snap-fit ​​cylinder control valve 8 are led out and connected to the two inlets of shuttle valve b 12, respectively. The outlet of shuttle valve b 12 is then connected to torque control valve 7, allowing a single torque control valve 7 to adjust both the snap-fit ​​torque and the unsnap torque.

[0034] The lower clamp control valve 4, the upper clamp control valve 5, and the punch cylinder control valve 8 are all load-sensitive electro-hydraulic multi-way valves with external load signal interfaces. The working port of the lower clamp control valve 4 is connected to the lower clamp 1 cylinder, the working port of the upper clamp control valve 5 is connected to the upper clamp 3 cylinder, and the working port of the punch cylinder control valve 8 is connected to the rod chamber and rodless chamber of the punch cylinder 10.

[0035] Both the clamping force control valve 6 and the torque control valve 7 are proportional electromagnetic relief valves.

[0036] The present invention provides an adaptive clamping force control system for iron drillers, which has two working processes for iron drillers' fastening and unfastening operations. The working processes are described in detail below with reference to the accompanying drawings.

[0037] (1) Upper-down operation:

[0038] The process of the top-down operation is as follows: Figure 2 As shown, the specific steps include the following:

[0039] Step 1: After starting the iron drill system, the operator selects the drill string model to be processed on the operating unit and sets the target value of the upper clamping torque. After this information is input into the PLC controller, the PLC controller outputs a control signal to the proportional amplifier corresponding to the clamping force control valve 6 based on the preset clamping force value data of the drill string model during the swivel operation. The preset clamping force value is 0.3 times the slippage critical clamping force value corresponding to the upper clamping torque target value. After the signal is amplified by the proportional amplifier, it controls and adjusts the proportional electromagnet of the clamping force control valve 6 to set the clamping force of the lower clamp 1 when matching the swivel. Then the program runs automatically, and the remote control relay drives the lower clamp control valve 4 to achieve clamping of the lower clamp 1. The swivel clamp starts the swivel operation. After 5 to 10 seconds of swivel, the swivel is completed.

[0040] Step 2: Based on the target torque value for the drill bit selected by the operator, the PLC controller outputs a control signal to the proportional amplifier corresponding to the torque control valve 7. After the signal is amplified by the proportional amplifier, it controls the proportional solenoid of the torque control valve 7 to adjust the set value of the torque control valve 7, thereby setting the initial torque value of the punch cylinder 10. This value is 0.2 to 0.3 times the target torque value. Then, the clamping force control valve 6 is adjusted to set the initial clamping force value of the upper clamp 3 and the lower clamp 1. This value is 1.2 to 1.3 times the critical clamping force value for slippage corresponding to the initial torque value. After that, the system program runs, and the PLC controller outputs a control signal to the remote control relays corresponding to the lower clamp control valve 4 and the upper clamp control valve 5. This controls the solenoids of the lower clamp control valve 4 and the upper clamp control valve 5 to switch the two valves, supplying oil to the lower clamp 1 and the upper clamp 3 to achieve clamping of the upper and lower clamps, completing the preparation work for the drill bit to make the top connection.

[0041] Step 3: When the upper clamping operation begins, the PLC controller outputs a control signal to the remote control relay corresponding to the upper clamping cylinder control valve 8. This controls the electromagnet of the upper clamping cylinder control valve 8 to switch the valve direction, supplying fluid to the upper clamping cylinder 10 to achieve the upper clamping action. The real-time torque of the upper clamping cylinder 10 is collected by the torque sensor 9 and transmitted to the PLC controller. Based on the torque change of the upper clamping cylinder 10, the PLC controller outputs a control signal to the proportional amplifier corresponding to the clamping force control valve 6 in real time. This controls the clamping force control valve 6 to adjust the clamping force of the lower clamp 1 and upper clamp 3 in real time, so that the clamping force changes synchronously with the torque change of the upper clamping cylinder 10. Simultaneously, the clamping force sensor 2 monitors the changes in the clamping force of the lower clamp 1 and upper clamp 3 and transmits this information to the PLC controller. The principle behind the change in clamping force value with torque value is as follows: the correspondence between the upper clamping torque value and the clamping force value at the critical slippage point of this type of drill bit is measured. During the upper clamping process, based on this correspondence, the clamping force value becomes 1.2 to 1.5 times the critical slippage clamping force value corresponding to the torque value.

[0042] Step 4: When the final torque value in step 3 reaches the upper clamping torque target value, the upper clamping action is completed. If the final torque value does not reach the upper clamping torque target value, the upper clamp 3 is released and reset, and steps 2 and 3 are repeated until the final torque value reaches the upper clamping torque target value.

[0043] Step 5: After the upper clamping action is completed, the upper clamp 3 and lower clamp 1 are released and reset. The system will create an array and number it for the drill pipe, recording the final values ​​of the clamping forces of the upper clamp 3 and lower clamp 1 fed back by the clamping force sensor 2 and the final value of the torque of the punch cylinder 10 monitored by the torque sensor 9 into this array. This data is used for system machine learning to optimize the initial values ​​of the clamping forces of the upper clamp 3 and lower clamp 1 for the next upper and lower clamping operation. The system records the new final values ​​of the clamping force and torque, overwriting the old final values, to achieve optimization and facilitate more efficient upper and lower clamping operations for drillers. This data recording can also be used for drill tool accident analysis.

[0044] (2) Unfastening operation:

[0045] The uncoupling operation process is as follows: Figure 3 As shown, the specific steps include the following:

[0046] Step 1: After starting the Iron Drill System, the operator selects the drill string model to be processed on the operating unit. After this information is input into the PLC controller, the PLC controller processes it through its internal control program and retrieves the final values ​​of the clamping force of the upper clamp 3 and lower clamp 1 and the final value of the torque of the punch cylinder 10 during the upper clamping operation of the drill string with this number stored in the database. Through the system's machine learning analysis, the initial value of the torque of the punch cylinder 10 and the initial value of the clamping force of the lower clamp 1 and upper clamp 3 for this unclamping operation are formed.

[0047] Step 2: Based on the initial torque and clamping force values ​​in Step 1, the PLC controller outputs control signals to the proportional amplifiers corresponding to the torque control valve 7 and clamping force control valve 6. After the signals are amplified by the proportional amplifiers, the torque control valve 7 and clamping force control valve 6 are controlled to achieve the initial value setting of the unhooking torque and clamping force. Then, the system controls the lower clamp control valve 4 and the upper clamp control valve 5 to achieve upper and lower clamping, completing the preparation work for the iron drill unhooking.

[0048] Step 3: After the uncoupling operation begins, the system controls the reversing of the control valve 8 of the punching cylinder, allowing oil to enter the plug chamber of the punching cylinder 10 to achieve the uncoupling action. When there is relative displacement between the upper clamp 3 and the lower clamp 1, the uncoupling is successful. If the uncoupling is unsuccessful, a new torque value and clamping force value are reset according to 1.3 times the original initial torque and clamping force values. The PLC controller outputs this control signal to the proportional amplifiers corresponding to the torque control valve 7 and the clamping force control valve 6. After the signal is amplified by the proportional amplifiers, the torque control valve 7 and the clamping force control valve 6 are controlled to modify the initial values ​​of the uncoupling torque and clamping force, and then the uncoupling process is restarted. If the uncoupling is successful, the system controls the upper clamp 3 to release, the lower clamp 1 to continue clamping, and the twisting pliers to start twisting. After twisting is completed, the twisting pliers release, the system lower clamp 1 releases, and the uncoupling operation is completed.

[0049] Step 4: After unhooking is completed, the system records the final clamping force values ​​of the upper clamp 3 and lower clamp 1 recorded by the clamping force sensor 2 and the final torque value of the punch cylinder 10 monitored by the torque sensor 9 to the database. This data is used for system machine learning and optimization of the initial clamping force values ​​of the upper clamp 3 and lower clamp 1 and the initial torque value of the punch cylinder 10 for the next unhooking operation. The system records the new final clamping force values ​​and final torque values, overwriting the old final clamping force values ​​and final torque values, in order to achieve the purpose of optimization and facilitate more efficient unhooking by iron drill operators.

[0050] The process of establishing the database of the control system of this invention is as follows:

[0051] After the system determines that the clamping is successful, the program sends the final clamping force value to the host computer via the Profinet protocol. Simultaneously, it sends an integer flag 'a', an integer variable 'b' representing the drill string type, and a Boolean storage flag variable 'c'. Upon receiving the storage flag variable 'c', the host computer stores the received clamping force value in a database that stores clamping force data for that type of drill string, based on the drill string type 'b'. This database contains multiple arrays, with array numbers corresponding to variable 'b', and array numbers within each array corresponding to variable 'a'. As the number flag 'a' increments, the storage space in the array also increases by one.

[0052] When uncoupling, the PLC controller sends the currently selected drill bit type to the host computer via variable b. The host computer searches for an array in the database via variable b and sends the last clamping force data stored in the array to the PLC controller. It also sends the current number to the PLC controller via variable a. The PLC controller uses the clamping force data sent by the host computer as the initial uncoupling clamping force.

[0053] The adaptive clamping force control system for iron drills of this invention works in tandem with two subsystems: a hydraulic control system and an electrical control system. Through machine learning, the system learns and analyzes past data on loading and unloading drill tools, automatically matching the optimal clamping force for different drill tools. Furthermore, the clamping force adapts to the changes in loading and unloading torque during the loading and unloading process of the drill tool. This solves the problems caused by the mismatch between the tightening and unloading torque and the clamping force when using different drill tools, such as drill tool damage, reduced success rate of loading and unloading operations, increased wear of the clamping mechanism, accelerated wear of the clamping teeth, and increased equipment maintenance costs.

Claims

1. A system for adaptive control of clamp force for iron roughneck, characterized in that, It comprises a hydraulic control system and an electric control system, both of which are controlled by a same PLC controller; An operation unit, a clamping force sensor (2) and a torque sensor (9) are connected to an input end of the PLC controller, and a remote control relay and a proportional amplifier are connected to an output end of the PLC controller, the remote control relay is connected to control electromagnets on a lower clamp control valve (4), an upper clamp control valve (5) and a punch cylinder control valve (8), and the proportional amplifier is connected to control electromagnets on a clamping force control valve (6) and a torque control valve (7); The lower clamp control valve (4) is connected to a lower clamp (1), the clamping force sensor (2) is installed on a connecting pipeline between the lower clamp control valve (4) and a lower clamp (1) cylinder plug cavity, the upper clamp control valve (5) is connected to an upper clamp (3), the upper clamp control valve (5) and the lower clamp control valve (4) are connected to the clamping force control valve (6), a rod cavity and a rodless cavity of the punch cylinder (10) are connected to two inlets of a shuttle valve a (11) respectively, an outlet of the shuttle valve a (11) is connected to the torque sensor (9) again, and two load signal external interfaces of the punch cylinder control valve (8) are connected to two inlets of a shuttle valve b (12) respectively after being led out, and an outlet of the shuttle valve b (12) is connected to the torque control valve (7) again. The two load signal external interfaces of the upper clamp control valve (5) and the lower clamp control valve (4) are respectively connected to a one-way valve, and the two one-way valves are connected to the clamping force control valve (6) after being combined.

2. The ironclad clamp force adaptive control system of claim 1, wherein, The lower clamp control valve (4), the upper clamp control valve (5) and the punch cylinder control valve (8) are load-sensitive electric control hydraulic multi-way valves with load signal external interfaces, a working oil port of the lower clamp control valve (4) is connected to a lower clamp (1) cylinder, a working oil port of the upper clamp control valve (5) is connected to an upper clamp (3) cylinder, and a working oil port of the punch cylinder control valve (8) is connected to a rod cavity and a rodless cavity of a punch cylinder (10).

3. The ironclad clamp force adaptive control system of claim 1, wherein, The clamping force control valve (6) and the torque control valve (7) are both selected to be proportional electromagnetic overflow valves.

4. A control method of the iron worker clamping force self-adaptive control system according to claim 1, including a make-up operation control method and a break-out operation control method, characterized in that, The upper make-up operation control method specifically comprises the following steps: Step 1, selecting a drill tool to be processed and setting an upper make-up torque target value, after the upper make-up torque target value is input into the PLC controller, the PLC controller outputs a control signal to a proportional amplifier corresponding to the clamping force control valve (6) according to preset clamping force value data of the drill tool under a make-up condition, the proportional amplifier amplifies the signal, controls a proportional electromagnet of the clamping force control valve (6), and then sets the clamping force of the lower clamp (1) under the make-up condition, and then the remote control relay drives the lower clamp control valve (4) to realize the clamping of the lower clamp (1), the make-up clamp starts the make-up operation, and the make-up is completed after 5-10 seconds. Step 2, the PLC controller outputs a control signal to the proportional amplifier corresponding to the torque control valve (7) according to the makeup torque target value of the selected drill tool in step 1, the signal is amplified through the proportional amplifier, then the proportional electromagnet of the torque control valve (7) is controlled, the proportional electromagnet adjusts the set value of the torque control valve (7), thereby setting the initial torque value of the makeup cylinder (10), and the initial clamping force value of the upper clamp (3) and the lower clamp (1) is set through the clamping force control valve (6), the PLC controller outputs a control signal to the remote control relay corresponding to the lower clamp control valve (4) and the upper clamp control valve (5), controls the electromagnet of the lower clamp control valve (4) and the upper clamp control valve (5) to realize the switching of the two valves, and supplies oil to the lower clamp (1) and the upper clamp (3) to realize the clamping of the upper and lower clamps, and the preparation work of the iron roughneck is completed; Step 3, when the makeup work starts, the PLC controller outputs a control signal to the remote control relay corresponding to the makeup cylinder control valve (8), controls the electromagnet of the makeup cylinder control valve (8) to realize the switching of the valve, supplies liquid to the makeup cylinder (10) to realize the makeup action, and collects the real-time torque of the makeup cylinder (10) through the torque sensor (9) and transmits it to the PLC controller, according to the torque change of the makeup cylinder (10), the PLC controller outputs a control signal to the proportional amplifier corresponding to the clamping force control valve (6) in real time, controls the clamping force control valve (6) to adjust the clamping force of the lower clamp (1) and the upper clamp (3) in real time, so that the clamping force changes synchronously with the torque change of the makeup cylinder (10), and at the same time, the clamping force sensor (2) monitors the clamping force change of the lower clamp (1) and the upper clamp (3) and transmits it to the PLC controller; Step 4, when the final torque value in step 3 reaches the makeup torque target value, the makeup action is completed, if the final torque value cannot reach the makeup torque target value, the upper clamp (3) is released and reset, and the above steps 2 and 3 are repeated until the final torque value reaches the makeup torque target value; Step 5, when the makeup action is completed, the upper clamp (3) and the lower clamp (1) are released and reset, the system establishes an array for the drill tool and numbers it, records the final value of the clamping force of the upper clamp (3) and the lower clamp (1) fed back by the clamping force sensor (2) and the torque final value of the makeup cylinder (10) monitored by the torque sensor (9) to the array, which is used for machine learning optimization of the system for the initial clamping force value of the upper clamp (3) and the lower clamp (1) in the next makeup and makeup operation; The makeup operation control method specifically includes the following steps: Step 1, select the drill tool type to be processed, the PLC controller forms the torque initial value of the makeup cylinder (10) and the initial clamping force value of the lower clamp (1) and the upper clamp (3) for this makeup operation according to the final value of the clamping force of the upper clamp (3) and the lower clamp (1) and the torque final value of the makeup cylinder (10) recorded during the makeup operation of the numbered drill tool; Step 2, the PLC controller outputs control signals to the proportional amplifiers corresponding to the torque control valve (7) and the clamping force control valve (6) according to the torque initial value and the clamping force initial value in step 1, and the signals are amplified by the proportional amplifiers to control the torque control valve (7) and the clamping force control valve (6) to achieve the initial value setting of the unbuckling torque and the clamping force, and then the system controls the upper jaw control valve (4) and the lower jaw control valve (5) to achieve the clamping of the upper jaw and the lower jaw, and the preparation work of the iron roughneck is completed; Step 3, after the unbuckling operation starts, the system controls the punch cylinder control valve (8) to reverse, and oil is supplied to the punch cylinder (10) to achieve the unbuckling action. When the upper jaw (3) and the lower jaw (1) have relative displacement, the unbuckling is successful. If the unbuckling is unsuccessful, the new torque value and the clamping force value are set according to 1.3 times of the original torque initial value and the clamping force initial value. The PLC controller outputs the control signals to the proportional amplifiers corresponding to the torque control valve (7) and the clamping force control valve (6), and the signals are amplified by the proportional amplifiers to control the torque control valve (7) and the clamping force control valve (6) to achieve the initial value modification of the unbuckling torque and the clamping force. Then, the unbuckling link is entered again. If the unbuckling is successful, the system controls the upper jaw (3) to release, the lower jaw (1) continues to clamp, the spinning jaw starts to spin, the spinning jaw releases after the spinning is completed, the lower jaw (1) releases, and the unbuckling operation is completed. Step 4, after the unbuckling is completed, the system records the final value of the clamping force of the upper jaw (3) and the lower jaw (1) recorded by the clamping force sensor (2) and the torque final value of the punch cylinder (10) monitored by the torque sensor (9) to the database, which is used for machine learning and optimization of the system for the clamping force initial value of the upper jaw (3) and the lower jaw (1) and the torque initial value of the punch cylinder (10) in the next unbuckling operation.

5. The control method of the ironclad clamp force self-adaptive control system according to claim 4, wherein, The principle of the change of the clamping force value with the torque value in the make-up operation control method is that the corresponding relationship between the make-up torque value and the clamping force value of the real-time measured slip criticality of the drilling tool of this type is measured. During the make-up process, according to the corresponding relationship, the clamping force value becomes 1.2-1.5 times of the slip criticality clamping force value corresponding to the torque value.

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