Continuous extrusion device and control method thereof

Abstract

The application discloses a continuous extrusion device and a control method thereof. The control method comprises the following steps: providing locking pressure to a shoe base mechanism through a limiting module to mechanically lock the shoe base mechanism; providing energy storage pressure to the shoe base mechanism through a hydraulic unit to compensate the pressure of the shoe base mechanism; a hydraulic lock is arranged on a compression circuit of the hydraulic unit, and the hydraulic unit forms the energy storage pressure through the hydraulic lock; the energy storage pressure is a low pressure that is more than twice the actual working pressure; the locking pressure is a low pressure of 3-5 Mpa; the energy storage pressure is a low pressure of 8-12 Mpa; the locking pressure is equal to the actual working pressure; the actual working pressure is determined based on the extrusion force generated by an extrusion wheel; the extrusion device is controlled to perform a copper rod extrusion operation on a copper rod delivered by a feeding device, and a finished product output by the extrusion device is received through a receiving device; during the copper rod extrusion operation, the copper rod extrusion operation of the extrusion device is dynamically adjusted to ensure production stability and precision.

Description

A continuous extrusion device and its control method Technical Field

[0001] This invention relates to the field of automation control technology, specifically to a continuous extrusion device and its control method. Background Technology

[0002] In the continuous extrusion process of copper, to ensure operational stability, a shoe holder is usually installed outside the extrusion roller. The shoe holder is directly pressed by controlling the drive end of the hydraulic cylinder. This ensures that the extrusion die mounted on the shoe holder is close to or against the extrusion roller, thus achieving stable copper rod extrusion. However, since the shoe holder is directly pressed by controlling the drive end of the hydraulic cylinder, after long-term operation, it is prone to wear of parts. When the pressure is lower than the set value, it is necessary to replenish and adjust the pressure in a timely and precise manner. Otherwise, the extrusion die will open outward (i.e., move away from the extrusion roller), resulting in copper leakage. At the same time, during the extrusion process, there is a strong nonlinear coupling relationship between the extrusion roller speed (speed parameter), the die inlet extrusion pressure (pressure parameter), and the die temperature (temperature parameter), which makes it impossible to achieve stable and controllable automated production operation and ensure production quality. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides a continuous extrusion device and its control method to solve the problems in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A control method for a continuous extrusion apparatus, the continuous extrusion apparatus comprising an extrusion wheel, a shoe support mechanism, and a clamping mechanism, the clamping mechanism comprising a limit module and a hydraulic unit, the control method comprising the following steps:

[0006] Switch the shoe seat mechanism to the clamping state;

[0007] Controlling the clamping mechanism to perform a locking operation on the boot seat mechanism includes: providing locking pressure to the boot seat mechanism through the limiting module to mechanically lock the boot seat mechanism; providing energy storage pressure to the boot seat mechanism through the hydraulic unit to compensate for pressure in the boot seat mechanism; a hydraulic lock is provided on the clamping circuit of the hydraulic unit; the hydraulic unit generates the energy storage pressure through the hydraulic lock; wherein, the energy storage pressure is a low pressure more than twice the actual working pressure, the locking pressure is a low pressure of 3-5 MPa, the energy storage pressure is a low pressure of 8-12 MPa, the locking pressure is equal to the actual working pressure, and the actual working pressure is determined based on the extrusion force generated by the extrusion wheel;

[0008] The extrusion device is controlled to perform copper rod extrusion operation on the copper rod conveyed by the feeding device, and the finished product output by the extrusion device is received by the receiving device; wherein, during the copper rod extrusion operation, multi-source monitoring data of the extrusion device is acquired in real time, and the copper rod extrusion operation of the extrusion device is dynamically adjusted according to the multi-source monitoring data;

[0009] After the copper rod pressing operation is completed, the clamping mechanism is controlled to perform an unlocking operation on the shoe seat mechanism;

[0010] After the unlocking operation is completed, the shoe seat mechanism is switched from the pressed state to the initial state;

[0011] The continuous extrusion device also includes a frame, the pressing mechanism also includes a positioning element, the positioning element is mounted on the frame, the hydraulic unit also includes a hydraulic cylinder, the hydraulic cylinder is rotatably connected to the frame, one end of the limiting module is rotatably connected to the drive end of the hydraulic cylinder, and the other end is rotatably connected to the positioning element, and the hydraulic lock is mounted on the pressing circuit of the hydraulic cylinder;

[0012] Controlling the clamping mechanism to perform a locking operation on the shoe seat mechanism includes:

[0013] The hydraulic cylinder is controlled to drive the limiting module to rotate around the positioning member, so that a locking position is formed between the limiting module and the positioning member to lock the shoe seat mechanism.

[0014] Switch the hydraulic lock to the locked state so that hydraulic oil that generates hydraulic energy is stored in the circuit from the hydraulic lock to the hydraulic cylinder to compensate for the locking pressure of the limit module.

[0015] Controlling the clamping mechanism to perform an unlocking operation on the boot seat mechanism includes:

[0016] Switch the hydraulic lock from the locked state to the open state to discharge the hydraulic oil stored in the circuit from the hydraulic lock to the hydraulic cylinder;

[0017] The hydraulic cylinder is controlled to drive the limit module to reset, thereby releasing the locking restriction of the locking position on the shoe seat mechanism.

[0018] In one embodiment, the boot seat mechanism includes a boot seat member, a first drive member, and an extrusion die. The extrusion die is mounted on the boot seat member, one end of the boot seat member is rotatably connected to the frame, and the boot seat member has an initial position and an extrusion position.

[0019] The control method further includes:

[0020] The first driving component is controlled to drive the shoe seat component to rotate from the initial position to the extrusion position, and to drive the extrusion die to abut against the extrusion wheel, so as to switch the shoe seat mechanism to the clamping state;

[0021] The first driving component is controlled to drive the shoe holder component to rotate from the extrusion position to the initial position, and to move the extrusion die away from the extrusion wheel, so as to switch the shoe holder mechanism from the pressing state to the initial state.

[0022] In one embodiment, the copper rod extrusion operation of the extrusion device is dynamically adjusted based on the multi-source monitoring data, including:

[0023] Multi-source monitoring data of the continuous extrusion device under preset extrusion conditions are collected in real time by multi-dimensional high-frequency sensors. The multi-source monitoring data includes extrusion wheel speed, die inlet extrusion pressure and die temperature.

[0024] Based on the multi-source monitoring data, a coupling-decoupling model is constructed, and a model predictive control algorithm is used to predict the changing trends of velocity, pressure, and temperature parameters within a preset time period, and to calculate the optimal adjustment amount for each parameter; wherein, the coupling-decoupling model is used to quantify the coupling relationship between velocity, pressure, and temperature parameters;

[0025] The current operating condition is determined based on the analysis results of the multi-source monitoring data and the coupling-decoupling model, and the control mode of the extrusion device is determined based on the current operating condition; wherein, the current operating condition is a steady-state operating condition or a dynamic operating condition;

[0026] Based on the control mode and the optimal adjustment amount of each parameter, the copper rod extrusion operation of the extrusion device is adjusted to adjust the speed of the extrusion wheel, the extrusion pressure at the die inlet, and the die temperature.

[0027] In one embodiment, the operation condition determination based on the multi-source monitoring data includes:

[0028] Based on the multi-source monitoring data, determine whether the parameter fluctuations, raw material hardness changes, and oxygen content fluctuations are all less than the steady-state threshold.

[0029] If so, then it is determined to be a steady-state operating condition.

[0030] If not, then it is determined to be a dynamic operating condition.

[0031] In one embodiment, switching to the corresponding control mode based on the determined operating condition includes:

[0032] When a dynamic operating condition characteristic is detected to persist for a first preset sampling period, the MPC control mode is switched to the PID control mode; wherein, the initial output value of the PID in the PID control mode inherits the last adjustment value of the MPC in the MPC control mode.

[0033] When the dynamic working condition ends and the parameters continue for the second preset sampling period, the system will smoothly transition through the difference and return to the MPC control mode.

[0034] If the dynamic operating condition is accompanied by extremely hard parameter constraints, lock the switching logic and prioritize the execution of safety controls.

[0035] In one embodiment, a coupling-decoupling model is constructed based on the multi-source monitoring data, including:

[0036] A mechanism model was constructed based on the aforementioned multi-source monitoring data;

[0037] The coupling coefficients are trained using a BP neural network and optimized using a genetic algorithm; wherein the coupling coefficients include the coupling coefficients of velocity to pressure, temperature to pressure, and velocity to temperature.

[0038] The pure copper low-temperature zone, pure copper high-temperature zone, and small-section zone are divided according to temperature range and product cross-section, and decoupling rules are formulated.

[0039] In one embodiment, it further includes:

[0040] The raw material fluctuations and die wear during the continuous extrusion process of copper are detected, and the coupling / decoupling model and control parameters are dynamically corrected based on the detection results.

[0041] A continuous extrusion apparatus, using the control method for a continuous extrusion apparatus as described in any of the above claims, includes a feeding device, an extrusion device, and a receiving device.

[0042] The feeding device, the extrusion device, and the receiving device are arranged sequentially along the conveying direction of the copper rod;

[0043] The copper rod input port of the extrusion device is equipped with a cutting mechanism that can be opened and closed;

[0044] The copper rod output end of the extrusion device is equipped with a shoe seat mechanism and a pressing mechanism; wherein, the pressing mechanism includes a limit module and a hydraulic unit, and the shoe seat mechanism has a locked state and an unlocked state;

[0045] When the boot seat mechanism switches from the initial state to the clamping state, the clamping mechanism performs a locking operation on the boot seat mechanism, including: providing locking pressure to the boot seat mechanism through the limiting module to mechanically lock the boot seat mechanism, and providing energy storage pressure to the boot seat mechanism through the hydraulic unit. The hydraulic unit is equipped with a hydraulic lock in its clamping circuit, and the hydraulic unit generates the energy storage pressure through the hydraulic lock. The energy storage pressure is a low pressure that is more than twice the actual working pressure, the locking pressure is a low pressure of 3-5 MPa, the energy storage pressure is a low pressure of 8-12 MPa, and the locking pressure is equal to the actual working pressure, which is determined based on the extrusion force generated by the extrusion wheel.

[0046] The extrusion device is used to perform copper rod extrusion operation on the copper rod conveyed by the feeding device, and the finished product output by the extrusion device is received by the receiving device; wherein, during the copper rod extrusion operation, multi-source monitoring data of the extrusion device is acquired in real time, and the copper rod extrusion operation of the extrusion device is dynamically adjusted according to the multi-source monitoring data.

[0047] Compared with existing technologies, the beneficial effects of this invention are as follows:

[0048] By using the limit module and hydraulic unit together, low-pressure locking and low-pressure compensation can be achieved for the shoe seat mechanism 13, thereby improving the reliability of the equipment. Compared with the traditional direct hydraulic cylinder locking method, the pressure of this clamping device is as low as 15% of the traditional method. Moreover, compared with the traditional mechanical locking method, due to the low locking pressure (working pressure) of this clamping device, pressure compensation can be achieved during operation through energy storage pressure. Attached Figure Description

[0049] Figure 1 is a flowchart of a control method for a continuous extrusion device according to one embodiment of the present invention;

[0050] Figure 2 is a flowchart of the sub-process of step S300 of the present invention;

[0051] Figure 3 is a schematic diagram of the boot seat mechanism of a continuous extrusion device in one embodiment of the present invention switching to the locked state;

[0052] Figure 4 is a schematic diagram of the boot seat mechanism of a continuous extrusion device in one embodiment of the present invention switching to the unlocked state;

[0053] Figure 5 is a schematic diagram of the structure of a continuous extrusion device provided in one embodiment of the present invention when the cutting mechanism is in the closed state;

[0054] Figure 6 is a schematic diagram of the structure of a continuous extrusion device provided in one embodiment of the present invention when the cutting mechanism is in the open state;

[0055] In the diagram: 11. Frame; 12. Cutting mechanism; 121. Mounting unit; 122. Rod breaking unit; 1221. Opening; 13. Shoe seat mechanism; 131. Shoe seat component; 1311. Extrusion section; 1312. Pressing end; 1313. Positioning block; 1314. Pressing block; 132. First driving component; 133. Extrusion die; 14. Pressing mechanism; 141. Positioning component; 142. Connecting component; 143. Pressing component; 1431. Second pressing surface; 144. Second driving component; 15. Extrusion roller. Detailed Implementation

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] As shown in Figures 1 to 6, the present invention provides a control method for a continuous extrusion device. The continuous extrusion device includes a frame 11, an extrusion wheel 15, a shoe holder mechanism 13, and a pressing mechanism 14. The pressing mechanism 14 includes a limit module and a hydraulic unit. The shoe holder mechanism 13 includes a shoe holder component 131, a first driving component 132, and an extrusion die 133. The extrusion die 133 is mounted on the shoe holder component 131. One end of the shoe holder component 131 is rotatably connected to the frame 11. The shoe holder component 131 has an initial position and an extrusion position. The control method includes the following steps:

[0058] S100, switch the shoe seat mechanism 13 to the pressing state; specifically, by controlling the first driving member 132 to drive the shoe seat member 131 to rotate from the initial position to the extrusion position, and drive the extrusion mold 133 to abut against the extrusion wheel 15, so as to switch the shoe seat mechanism 13 to the pressing state.

[0059] S200, the control clamping mechanism 14 performs a locking operation on the shoe seat mechanism 13, including: providing locking pressure to the shoe seat mechanism 13 through the limit module to mechanically lock the shoe seat mechanism 13; providing energy storage pressure to the shoe seat mechanism 13 through the hydraulic unit to compensate for the pressure of the shoe seat mechanism 13; the hydraulic unit is equipped with a hydraulic lock in the clamping circuit; the hydraulic unit forms energy storage pressure through the hydraulic lock; wherein, the energy storage pressure is a low pressure more than twice the actual working pressure, the locking pressure is a low pressure of 3-5 MPa, the energy storage pressure is a low pressure of 8-12 MPa, the locking pressure is equal to the actual working pressure, and the actual working pressure is determined based on the extrusion force generated by the extrusion wheel 15;

[0060] In this embodiment, when locking the shoe seat mechanism 13 (i.e., shoe seat component 131), the shoe seat component 131 is first locked mechanically by the limiting module, and at the same time the hydraulic lock of the hydraulic unit is locked so that hydraulic energy (i.e., energy storage pressure) is stored in the circuit of the hydraulic lock to the oil cylinder, so as to compensate for the locking pressure of the mechanical structure.

[0061] By using the limit module and hydraulic unit together, low-pressure locking and low-pressure compensation can be achieved for the shoe seat mechanism 13, thereby improving the reliability of the equipment. Compared with the traditional direct hydraulic cylinder locking method, the pressure of this clamping device is as low as 15% of the traditional method. Moreover, compared with the traditional mechanical locking method, due to the low locking pressure (working pressure) of this clamping device, pressure compensation can be achieved during operation through energy storage pressure.

[0062] The hydraulic lock is a hydraulically controlled check valve, a technology already in use. By installing the hydraulic lock on the oil pipe of the hydraulic unit, hydraulic oil can only flow from A to B during operation. When opening is needed, oil flowing through port X will open the hydraulic lock. When the extrusion operation ends, the pressure oil needs to be released before the limit module and shoe seat 131 can be opened. When opening is needed, oil flowing through port X will open the hydraulic lock, thus achieving the following: when the hydraulic cylinder retracts (eliminating the accumulator pressure and locking pressure), the hydraulic oil between the hydraulic lock and the hydraulic cylinder circuit flows from B to port X for discharge, avoiding the one-way conduction of the check valve from affecting the extension and retraction of the hydraulic cylinder.

[0063] It should be noted that similar structures on the market rely on direct hydraulic cylinder clamping. Due to the high pressure of the corresponding hydraulic cylinder, the current locking pressure is usually 20 MPa or even 40 MPa. The hydraulic locking devices on the market cannot achieve low-pressure locking of 3-5 MPa for the shoe seat mechanism 13, nor can they achieve low-pressure energy storage compensation. If double hydraulic compensation is performed, that is, if two times the hydraulic pressure is stored, it will be in an ultra-high pressure state. Obviously, this high-pressure locking method will make the hydraulic circuit unsafe and unreliable, unable to guarantee working stability and safety, and easily lead to copper leakage.

[0064] It should be noted that the actual working pressure depends on the squeezing pressure, and the locking pressure is equal to the working pressure; the energy storage pressure is the part higher than the locking pressure. That is, assuming the working pressure is 5 MPa and the energy storage pressure is 12 MPa, then there is 7 MPa of hydraulic energy stored in the circuit from the hydraulic lock to the oil cylinder.

[0065] In one embodiment, the clamping mechanism 14 further includes a positioning element 141, which is mounted on the frame 11. The hydraulic unit further includes a second driving element 144 (i.e., a hydraulic cylinder), which is rotatably connected to the frame 11. One end of the limiting module is rotatably connected to the driving end of the hydraulic cylinder, and the other end is rotatably connected to the positioning element 141. A hydraulic lock is mounted on the clamping circuit of the hydraulic cylinder.

[0066] In one embodiment, controlling the clamping mechanism 14 to perform a locking operation on the shoe seat mechanism 13 includes:

[0067] S210, Control the hydraulic cylinder to drive the limit module to rotate around the positioning member 141, so that a locking position is formed between the limit module and the positioning member 141 to lock the shoe seat mechanism 13.

[0068] In one embodiment, the limiting module includes:

[0069] Connector 142, one end of which is rotatably connected to positioning member 141;

[0070] The clamping member 143 is installed on the other end of the connecting member 142, and one end of the clamping member 143 is rotatably connected to the driving end of the second driving member 144; wherein, the positioning member 141 and the clamping member 143 are located on the same surface of the connecting member 142, and when the limiting module is in the locked position, a locking position is formed between the clamping member 143 and the positioning member 141.

[0071] In this embodiment, the limiting module includes a connector 142 and a clamping member 143. One end of the connector 142 is rotatably connected to the positioning member 141, and the clamping member 143 is installed on the end of the connector 142 away from the positioning member 141. One end of the clamping member 143 is rotatably connected to the driving end of the second driving member 144, so as to adjust the position of the clamping member 143. This ensures that when the clamping device is in the clamping state, the clamping end 1312 is locked between the positioning member 141 and the clamping member 143, so as to ensure that the extrusion part 1311 can be tightly pressed against the outer surface of the extrusion wheel 15.

[0072] In one embodiment, a clamping end 1312 is provided at the end of the shoe seat member 131 away from the rotating hole. When the clamping device is in the clamping state, the clamping end 1312 is located between the positioning member 141 and the clamping member 143. A positioning block 1313 and a clamping block 1314 are respectively installed on both sides of the clamping end 1312. The positioning block 1313 is provided with a first positioning surface, and the clamping block 1314 is provided with a first clamping surface. The first positioning surface and the first clamping surface protrude from the two side surfaces of the clamping end 1312, respectively. The first clamping surface is inclined relative to the first positioning surface, and there is a first preset angle between the first positioning surface and the first clamping surface.

[0073] The positioning member 141 has a second positioning surface that fits against the first positioning surface, and the clamping member 143 has a second clamping surface 1431 that fits against the first clamping surface, wherein the second positioning surface is arranged in a vertical plane.

[0074] In this embodiment, positioning blocks 1313 and pressing blocks 1314 are detachably installed on both sides of the pressing end 1312 of the shoe seat 131. When the positioning blocks 1313 and pressing blocks 1314 are installed on both sides of the pressing end 1312, the first positioning surface of the positioning block 1313 and the first pressing surface of the pressing block 1314 protrude from both sides of the pressing end 1312, so that when the pressing device is in the pressing state, the second positioning surface of the positioning member 141 and the second pressing surface 1431 of the pressing member 143 respectively fit and press against the first positioning surface of the positioning block 1313 and the first pressing surface of the pressing block 1314, thereby ensuring working stability. Since the positioning blocks 1313 and pressing blocks 1314 are detachably installed on the pressing end 1312 of the pressing module, the positioning blocks 1313 and pressing blocks 1314 can be disassembled and replaced according to working needs, improving the flexibility of equipment use and reducing maintenance and replacement costs.

[0075] It should be noted that, since the first pressing surface is inclined relative to the first positioning surface, and the angle between the first pressing surface and the first positioning surface is 5-30 degrees, the pressing force between the pressing block 1314 and the pressing member 143 can be adaptively adjusted during operation, so as to avoid the pressing block 1314 and the pressing member 143 from locking together due to the pressing operation, thereby facilitating the opening of the pressing mechanism 14 and the shoe seat mechanism 13.

[0076] S220. Switch the hydraulic lock to the locked state so that hydraulic oil that generates hydraulic energy is stored in the circuit from the hydraulic lock to the hydraulic cylinder to compensate for the locking pressure of the limit module.

[0077] S300: Control the extrusion device to perform copper rod extrusion operation on the copper rod conveyed by the feeding device, and receive the finished product output by the extrusion device through the receiving device;

[0078] During continuous copper extrusion, there is a strong nonlinear coupling relationship between the extrusion roller speed (speed parameter), the die inlet extrusion pressure (pressure parameter), and the die temperature (temperature parameter). For example, increasing the speed increases the frictional heat between the copper billet and the extrusion roller, leading to an increase in copper temperature and enhanced plasticity, which in turn reduces the extrusion pressure. Conversely, excessive extrusion pressure inhibits the copper flow velocity, causing fluctuations in the extrusion roller speed, resulting in abnormal frictional heat and temperature runaway. Furthermore, abnormal die temperature (too high / too low) alters the copper viscosity, further exacerbating the coupling fluctuations between speed and pressure. These strong coupling characteristics of speed, pressure, and temperature parameters make traditional single-variable control insufficient for high-precision production requirements.

[0079] Therefore, during the copper rod extrusion operation, this invention acquires multi-source monitoring data of the extrusion device and dynamically adjusts the copper rod extrusion operation of the extrusion device based on the multi-source monitoring data; including:

[0080] S310. Real-time acquisition of multi-source monitoring data of the continuous extrusion unit under preset extrusion conditions via multi-dimensional high-frequency sensors. The multi-source monitoring data includes the extrusion roller speed, die inlet extrusion pressure, and die temperature. Specifically:

[0081] A speed sensor is installed at the end of the extrusion roller 15 shaft, and the rotational speed of the extrusion roller 15 is obtained in real time based on the speed sensor.

[0082] A pressure sensor is installed on the wall of the mold inlet flow channel, and the extrusion pressure at the mold inlet is collected in real time based on the pressure sensor.

[0083] Temperature sensors are installed around the mold cavity, and the mold temperature is collected in real time based on the temperature sensors.

[0084] Align the extrusion roller speed, die inlet extrusion pressure, and die temperature according to timestamps;

[0085] Kalman filtering is used to remove electromagnetic interference pulses, and sliding window filtering is used to smooth the rotational speed data to obtain multi-source monitoring data;

[0086] Among them, the multi-dimensional high-frequency sensors include speed sensors, temperature sensors, and pressure sensors.

[0087] S320. A coupling-decoupling model is constructed based on multi-source monitoring data, and a model predictive control algorithm is used to predict the changing trends of velocity, pressure, and temperature parameters within a preset time period in the future, and to calculate the optimal adjustment amount of each parameter; wherein, the coupling-decoupling model is used to quantify the coupling relationship between velocity, pressure, and temperature parameters;

[0088] In one embodiment, a coupling-decoupling model is constructed based on multi-source monitoring data, including:

[0089] A mechanism model was constructed based on multi-source monitoring data;

[0090] Specifically, based on the theory of plastic deformation of copper, the formula for frictional heat is derived:

[0091] And the liquidity-stress formula: Where Q is the frictional heat between the copper billet and the extrusion roller 15, k is the material coefficient (e.g., pure copper k=0.0025, brass k=0.0028), S is the rotational speed of the extrusion roller 15, P is the extrusion pressure at the die inlet, μ is the coefficient of friction, K is the die coefficient (e.g., pipe K=1200, profile K=800), η is the viscosity of the copper material (decreases with increasing temperature), and v is the flow velocity of the copper material.

[0092] The coupling coefficients (Ksp, Ktp, Kst) are trained using a BP neural network and optimized using a genetic algorithm. The coupling coefficients include the velocity-pressure coupling coefficient Ksp, the temperature-pressure coupling coefficient Ktp, and the velocity-temperature coupling coefficient Kst.

[0093] In this embodiment, the coupling coefficients are trained by a BP neural network. The input of the neural network is the historical and current speed, pressure and temperature sequence, and the output is the predicted pressure and temperature values ​​for the next moment. By comparing the error between the predicted value and the actual value, the network weights are optimized by backpropagation. Finally, the dynamic coupling coefficients of speed to pressure, temperature to pressure, and speed to temperature are extracted from the hidden layer relationship of the network. The network weights are then optimized by a genetic algorithm so that the prediction error of the coupling coefficient is ≤3%.

[0094] The BP neural network uses a 3-layer structure (3 neurons in the input layer: speed, pressure, and temperature; 10 neurons in the hidden layer; and 2 neurons in the output layer: predicted pressure and predicted temperature). The training data consists of 1000 sets (covering operating conditions of 60-100 r / min speed, 150-250 MPa pressure, and 600-850℃ temperature). The training parameters are: learning rate 0.01, number of iterations 5000, error threshold 0.001, and the activation function is the Sigmoid function.

[0095] The pure copper low-temperature zone, pure copper high-temperature zone, and small-section zone are divided according to temperature range and product cross-section, and decoupling rules are formulated.

[0096] Preferably, the three operating conditions include the low-temperature region of pure copper (e.g., T<650℃), the high-temperature region of pure copper (e.g., T>750℃), and the small cross-section region (e.g., wall thickness <1mm); the decoupling rules are: Ksp=0.8 for the low-temperature region of pure copper, Ktp=0.9 for the high-temperature region of pure copper, and Kst=0.9 for the small cross-section region.

[0097] In one embodiment, a model predictive control algorithm is used to predict the changing trends of speed, pressure, and temperature parameters within a preset time period, and the optimal adjustment amount for each parameter is calculated, including:

[0098] MPC parameter configuration, objective function:

[0099]

[0100] Where J is the optimization objective function, , , These are the target values ​​for pressure, speed, and temperature, respectively. , , These are the predicted pressure, velocity, and temperature values, respectively, with hard and soft constraints embedded.

[0101] In this embodiment, the set hard constraints include: the die temperature must not exceed 850°C, the die inlet extrusion pressure must not exceed 250 MPa, and the speed fluctuation of the extrusion roller 15 must not exceed ±5% of the set value. When any parameter touches or exceeds the hard constraints, the system locks the current control mode and prioritizes the execution of safety control strategies, including but not limited to: immediately reducing the speed of the extrusion roller 15 by 50% and triggering an audible and visual alarm. If the parameters do not return to the safe range within 3 seconds, an emergency shutdown procedure is executed.

[0102] The soft constraint range can be customized based on product quality requirements, such as: mold temperature 700-800℃, mold inlet extrusion pressure 180-240MPa, and extrusion roller speed 70-90r / min (the upper limit of speed for small cross-section products is reduced to 85r / min).

[0103] Based on the decoupled model, the parameter values ​​are predicted within a preset time period. If the predicted values ​​exceed the soft constraints, the optimal adjustment amount of each parameter is obtained by calculating using a quadratic programming algorithm.

[0104] S330. Determine the current operating condition based on the analysis results of multi-source monitoring data and coupling / decoupling models, and determine the control mode of the extrusion device based on the current operating condition; wherein, the current operating condition is a steady-state operating condition or a dynamic operating condition;

[0105] In one embodiment, the operation condition determination based on multi-source monitoring data includes:

[0106] Based on multi-source monitoring data, determine whether parameter fluctuations, raw material hardness changes, and oxygen content fluctuations are all less than the steady-state threshold;

[0107] If yes, it is determined to be a steady-state operating condition; otherwise, it is determined to be a dynamic operating condition.

[0108] When dynamic operating condition characteristics are detected to persist for the first preset sampling period, the MPC control mode is switched to the PID control mode; wherein, the initial output value of the PID in the PID control mode inherits the last adjustment of the MPC in the MPC control mode.

[0109] When the dynamic working condition ends and the parameters continue for the second preset sampling period, the system will smoothly transition through the difference and return to the MPC control mode.

[0110] If the dynamic operating condition is accompanied by extremely hard parameter constraints, lock the switching logic and prioritize the execution of safety controls.

[0111] If the parameters are subject to overly strict constraints, at least one of the following operations shall be performed immediately:

[0112] Reduce the rotational speed of extrusion roller 15 to a safe range;

[0113] Trigger the cooling system to lower the mold temperature;

[0114] If the system does not recover within 3 seconds, perform an emergency stop and record the fault code.

[0115] In this embodiment, the current operating condition is determined based on multi-source monitoring data, avoiding the problem of switching control modes relying on manual experience or simple threshold judgments, which can lead to switching lag and parameter abrupt changes. For example, when the hardness of the raw material changes abruptly, the prediction model of MPC cannot respond in time and still uses the steady-state control strategy, resulting in excessive pressure fluctuations. When switching to PID, if the initial parameter settings are not reasonable, it will cause a step change in speed or temperature, further aggravating product defects.

[0116] The fast PID parameters are configured as follows: proportional gain Kp = 0.45 (50% improvement over steady state), integral gain Ki = 0.2 (100% improvement), derivative gain Kd = 0.03 (40% reduction). The integral term saturates when the deviation is > ±5% to avoid overshoot.

[0117] The steady-state threshold can be set based on historical data statistics, such as parameter fluctuation range < ±2%, raw material hardness change < 5%, and oxygen content fluctuation < 0.1%. The first preset sampling period can be 5 periods, and the second preset sampling period can be 10 periods.

[0118] This invention effectively avoids situations where the dynamic characteristics of the actuator are not considered (e.g., the hydraulic valve responds slowly in MPC mode and needs to respond faster in PID mode), resulting in poor command delivery. At the same time, the correction results of the dynamic compensation module are not fed back to the control mode switching logic in a timely manner, causing the switching timing to lag behind the actual changes in working conditions.

[0119] S340. Based on the control mode and the optimal adjustment amount of each parameter, adjust the copper rod extrusion operation of the extrusion device to adjust the speed of the extrusion roller 15, the extrusion pressure at the die inlet, and the die temperature.

[0120] In one embodiment, it further includes:

[0121] S350 detects raw material fluctuations and die wear during continuous copper extrusion, and dynamically corrects the coupling / decoupling model and control parameters based on the detection results. Specifically:

[0122] Adjust the friction coefficient and rotation speed according to the hardness of the copper billet, and correct the temperature target according to the oxygen content;

[0123] Pressure targets and rotational speeds are adjusted based on the standard deviation σ of pressure fluctuations.

[0124] Die wear is assessed by monitoring the long-term, slow upward trend of the die inlet pressure. Significant wear is identified when the pressure rises above a preset value (e.g., 5% of the initial value) within a continuous, preset production time (e.g., 10 minutes). Based on the detection results, the BP neural network is fine-tuned online by adding new production data to the training set to dynamically correct the coupling / decoupling model. Simultaneously, the friction coefficient μ in the mechanistic model is updated based on the measured hardness of the copper billet.

[0125] The standard deviation of pressure fluctuation σ is divided into 3 levels, corresponding to different adjustment strategies:

[0126] Level 1 (σ < 0.5 MPa): Pressure target fine-tuning ±2 MPa, rotation speed fine-tuning ±1 r / min;

[0127] Level 2 (0.5MPa≤σ<1.0MPa): Pressure target adjustment ±5MPa, speed adjustment ±3r / min;

[0128] Level 3 (σ≥1.0MPa): Pressure target adjustment ±8MPa, rotation speed adjustment ±5r / min, and trigger mold wear detection (to eliminate pressure fluctuations caused by wear).

[0129] Determining mold wear requires excluding interference from raw material fluctuations: When pressure continuously rises (>5% increase within 10 minutes), first verify whether the raw material hardness / oxygen content is stable (fluctuation < steady-state threshold) – if stable, it is determined to be mold wear; if unstable, it is determined to be raw material fluctuation. The coupling / decoupling model correction for mold wear: If wear causes a pressure increase ΔP (MPa), the coupling coefficient Ksp of velocity to pressure is corrected to Ksp'=Ksp+0.002×ΔP; for example, when ΔP=10MPa, Ksp'=0.8+0.002×10=0.82.

[0130] This invention establishes a multi-dimensional quantitative judgment standard, combining parameter fluctuation range and raw material characteristic changes (hardness, oxygen content) to form a hard index for judging working conditions, thereby improving the accuracy of working condition judgment, avoiding invalid parameter adjustments due to misjudgment, and improving the stability of copper material cross-sectional dimensions.

[0131] By employing parameter inheritance and transition compensation switching logic, parameter abrupt changes are avoided, reducing parameter fluctuations and surface scratch defect rates during the switching process, and ensuring product wall thickness uniformity. By constructing real-time feedback for detection, modeling, control, execution, and compensation, control lag is reduced, ensuring improved synchronization between parameter adjustment commands and their implementation. Even in the face of sudden changes in raw material hardness or slight mold wear, parameters can be stabilized within 30ms, extending production stability (continuous pass time). This invention enables precise control of speed, pressure, and temperature, improving operational adaptability and ensuring product quality.

[0132] Control methods also include:

[0133] S400. After the copper rod pressing operation is completed, the clamping mechanism 14 is controlled to perform an unlocking operation on the shoe seat mechanism 13; including:

[0134] S410. Switch the hydraulic lock from the locked state to the open state to discharge the hydraulic oil stored in the circuit from the hydraulic lock to the hydraulic cylinder.

[0135] S420: Control the hydraulic cylinder to drive the limit module to reset, so as to release the locking restriction of the locking position on the shoe seat mechanism 13.

[0136] S500. After the unlocking operation is completed, the shoe seat mechanism 13 is switched from the pressing state to the initial state. Specifically, this includes controlling the first driving member 132 to drive the shoe seat member 131 to rotate from the extrusion position to the initial position, and driving the extrusion mold 133 away from the extrusion wheel 15, so as to switch the shoe seat mechanism 13 from the pressing state to the initial state.

[0137] A control system for a continuous extrusion apparatus, using a control method for a continuous extrusion apparatus as described above, includes:

[0138] The locking control module is used to control the shoe base mechanism 13 to switch to the locked state;

[0139] The extrusion control module is used to control the extrusion device to perform copper rod extrusion operation on the copper rod conveyed by the feeding device, and to receive the finished product output by the extrusion device through the receiving device;

[0140] The dynamic adjustment module is used to acquire multi-source monitoring data of the extrusion device during the copper rod extrusion operation and to dynamically adjust the copper rod extrusion operation of the extrusion device based on the multi-source monitoring data.

[0141] The dynamic adjustment module includes:

[0142] The data acquisition submodule is used to collect multi-source monitoring data of the continuous extrusion device under preset extrusion conditions in real time through multi-dimensional high-frequency sensors. The multi-source monitoring data includes the speed of the extrusion roller 15, the extrusion pressure at the die inlet, the copper billet temperature and the die temperature.

[0143] The calculation submodule is used to construct a coupling-decoupling model based on multi-source monitoring data, and to use a model predictive control algorithm to predict the changing trends of velocity, pressure and temperature parameters within a preset time period, and to calculate the optimal adjustment amount of each parameter; among them, the coupling-decoupling model is used to quantify the coupling relationship between velocity, pressure and temperature parameters.

[0144] The determination submodule is used to determine the current operating condition based on multi-source monitoring data, and to determine the control mode of the extrusion device based on the current operating condition; wherein the current operating condition is a steady-state operating condition or a dynamic operating condition;

[0145] The adjustment submodule is used to adjust the copper rod extrusion operation of the extrusion device according to the control mode and the optimal adjustment amount of each parameter, so as to adjust the speed of the extrusion roller 15, the extrusion pressure at the die inlet, and the die temperature.

[0146] A continuous extrusion apparatus, using the control method of a continuous extrusion apparatus as described above, includes a feeding device, an extrusion device, and a receiving device.

[0147] The feeding device, extrusion device, and receiving device are arranged sequentially along the conveying direction of the copper rod;

[0148] As shown in Figures 5 and 6, a cutting mechanism 12 is installed in the copper rod input port of the extrusion device in an openable manner; wherein, the cutting module includes an installation unit 121 and a rod breaking unit 122, one side of the rod breaking unit 122 is rotatably connected to the rod input port through the installation unit 121, and the other side of the rod breaking unit 122 is provided with an opening 1221 for conveying the metal rod, and the opening 1221 of the rod breaking unit 122 is provided facing and penetrating the side away from the installation unit 121.

[0149] In this embodiment, the rod cutting unit 122 is mounted on the rod inlet side of the extrusion mechanism via the mounting unit 121, and one side of the rod breaking unit 122 is rotatably connected to the mounting unit 121. This allows the cutting mechanism 12 to be switched to an open or closed state during operation. Furthermore, by providing an opening 1221 on the rod breaking unit 122, the metal rod can easily detach from the rod breaking unit 122 through the opening 1221 of the cutting module when the extrusion assembly switches from the closed to the open state, thus avoiding interference with the rod breaking unit 122 during extrusion. The feed port of the mechanism is open, allowing operators to directly manipulate the break rod unit 122 during operation. This allows the break rod unit 122 to rotate around the side connected to the mounting unit 121, enabling the extrusion assembly to switch between open and closed states without first stopping the extrusion output and then disassembling the scraper assembly from the extrusion mechanism to observe its internal workings. This improves operational convenience, facilitates observation of the scraper assembly and the feed rod of the extrusion wheel 15, and effectively avoids impacting production efficiency. The scraper assembly is installed on top, making operation convenient.

[0150] The copper rod output end of the extrusion device is equipped with a shoe seat mechanism 13 and a pressing mechanism 14; wherein, the pressing mechanism 14 includes a limit module and a hydraulic unit, and the shoe seat mechanism 13 has a pressing state and an initial state;

[0151] When the shoe seat mechanism 13 switches from the initial state to the clamping state, the clamping mechanism 14 performs a locking operation on the shoe seat mechanism 13, including: providing locking pressure to the shoe seat mechanism 13 through the limit module to mechanically lock the shoe seat mechanism 13, and providing energy storage pressure to the shoe seat mechanism 13 through the hydraulic unit. The hydraulic unit is equipped with a hydraulic lock in the clamping circuit, and the hydraulic unit forms energy storage pressure through the hydraulic lock. The energy storage pressure is a low pressure that is more than twice the actual working pressure, the locking pressure is a low pressure of 3-5 MPa, the energy storage pressure is a low pressure of 8-12 MPa, and the locking pressure is equal to the actual working pressure, which is determined based on the extrusion force generated by the extrusion wheel 15.

[0152] The extrusion device is used to perform copper rod extrusion operation on the copper rod conveyed by the feeding device, and to receive the finished product output by the extrusion device through the receiving device. During the copper rod extrusion operation, multi-source monitoring data of the extrusion device is acquired in real time, and the copper rod extrusion operation of the extrusion device is dynamically adjusted according to the multi-source monitoring data.

[0153] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it is obvious that many changes and variations can be made based on the above teachings. Although embodiments of the invention have been shown and described, these specific embodiments are merely explanations of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. The purpose of selecting and describing exemplary embodiments is to explain the specific principles of the invention and its practical application, so that those skilled in the art, after reading this specification, can make modifications, substitutions, variations, and various choices and changes to the embodiments as needed without departing from the principles and spirit of the invention, provided that such modifications, substitutions, variations, and choices and changes are within the scope of the claims of the invention and are protected by patent law.

Claims

1. A control method for a continuous extrusion device, characterized in that, The continuous extrusion device includes an extrusion wheel, a shoe seat mechanism, and a clamping mechanism. The clamping mechanism includes a limiting module and a hydraulic unit. The control method includes the following steps: switching the shoe seat mechanism to a clamping state; controlling the clamping mechanism to perform a locking operation on the shoe seat mechanism, including: providing locking pressure to the shoe seat mechanism through the limiting module to mechanically lock the shoe seat mechanism; providing energy storage pressure to the shoe seat mechanism through the hydraulic unit to compensate for pressure on the shoe seat mechanism; a hydraulic lock is provided on the clamping circuit of the hydraulic unit, and the hydraulic unit forms the energy storage pressure through the hydraulic lock; In this process, the energy storage pressure is a low-pressure pressure that is more than twice the actual working pressure, the locking pressure is a low-pressure pressure of 3-5 MPa, the energy storage pressure is a low-pressure pressure of 8-12 MPa, and the locking pressure is equal to the actual working pressure, which is determined based on the extrusion force generated by the extrusion roller. The extrusion device is controlled to perform a copper rod extrusion operation on the copper rod conveyed by the feeding device, and the finished product output by the extrusion device is received by the receiving device. During the copper rod extrusion operation, the copper rod extrusion operation of the extrusion device is dynamically adjusted. After the copper rod extrusion operation is completed, the clamping mechanism is controlled to... The boot seat mechanism performs an unlocking operation; after the unlocking operation is completed, the boot seat mechanism is switched from the clamping state to the initial state; the continuous extrusion device also includes a frame, the clamping mechanism also includes a positioning element, the positioning element is mounted on the frame, the hydraulic unit also includes a hydraulic cylinder, the hydraulic cylinder is rotatably connected to the frame, one end of the limiting module is rotatably connected to the drive end of the hydraulic cylinder, and the other end is rotatably connected to the positioning element, the hydraulic lock is mounted on the clamping circuit of the hydraulic cylinder; controlling the clamping mechanism to perform a locking operation on the boot seat mechanism includes: controlling the hydraulic cylinder to drive the limiting module around the positioning element. The component rotates to form a locking position between the limiting module and the positioning component, which locks the shoe seat mechanism; the hydraulic lock is switched to the locked state so that hydraulic oil generating hydraulic energy is stored in the circuit from the hydraulic lock to the hydraulic cylinder to compensate for the locking pressure of the limiting module; the clamping mechanism is controlled to perform an unlocking operation on the shoe seat mechanism, including: switching the hydraulic lock from the locked state to the open state to discharge the hydraulic oil stored in the circuit from the hydraulic lock to the hydraulic cylinder; and controlling the hydraulic cylinder to drive the limiting module to reset to release the locking restriction of the locking position on the shoe seat mechanism.

2. The control method for a continuous extrusion device according to claim 1, characterized in that, The shoe seat mechanism includes a shoe seat component, a first driving component, and an extrusion die. The extrusion die is mounted on the shoe seat component, and one end of the shoe seat component is rotatably connected to the frame. The shoe seat component has an initial position and an extrusion position. The control method further includes: controlling the first driving component to drive the shoe seat component to rotate from the initial position to the extrusion position, and causing the extrusion die to abut against the extrusion wheel, so as to switch the shoe seat mechanism to a pressing state; controlling the first driving component to drive the shoe seat component to rotate from the extrusion position to the initial position, and causing the extrusion die to move away from the extrusion wheel, so as to switch the shoe seat mechanism from the pressing state to the initial state.

3. The control method for a continuous extrusion device according to claim 1, characterized in that, The dynamic adjustment of the copper rod extrusion operation of the extrusion device includes: real-time acquisition of multi-source monitoring data of the continuous extrusion device under preset extrusion conditions using multi-dimensional high-frequency sensors, the multi-source monitoring data including extrusion wheel speed, die inlet extrusion pressure, and die temperature; construction of a coupling-decoupling model based on the multi-source monitoring data, and prediction of the changing trends of speed, pressure, and temperature parameters within a preset time period using a model predictive control algorithm, calculating the optimal adjustment amount for each parameter; wherein, the coupling-decoupling model is used to quantify the coupling relationship between speed, pressure, and temperature parameters; determination of the current operating condition based on the multi-source monitoring data and the analysis results of the coupling-decoupling model, and determination of the control mode of the extrusion device based on the current operating condition; wherein, the current operating condition is a steady-state condition or a dynamic condition; and adjustment of the copper rod extrusion operation of the extrusion device according to the control mode and the optimal adjustment amount for each parameter, to adjust the extrusion wheel speed, die inlet extrusion pressure, and die temperature.

4. The control method for a continuous extrusion device according to claim 3, characterized in that, The operating condition is determined based on the multi-source monitoring data, including: determining whether the parameter fluctuation, raw material hardness change, and oxygen content fluctuation are all less than the steady-state threshold; if so, it is determined to be a steady-state operating condition; if not, it is determined to be a dynamic operating condition.

5. The control method for a continuous extrusion device according to claim 3, characterized in that, The control mode is switched to the corresponding control mode based on the determined operating condition, including: when the dynamic operating condition characteristics are detected to last for a first preset sampling period, the MPC control mode is switched to the PID control mode; wherein, the initial output value of the PID in the PID control mode inherits the last adjustment amount of the MPC in the MPC control mode; when the dynamic operating condition ends and the parameters last for a second preset sampling period, the control mode is restored to MPC control mode through differential smoothing transition; if the dynamic operating condition is accompanied by parameter over-hard constraints, the switching logic is locked and safety control is executed first.

6. The control method for a continuous extrusion device according to claim 3, characterized in that, The coupling-decoupling model is constructed based on the multi-source monitoring data, including: constructing a mechanism model based on the multi-source monitoring data; training coupling coefficients through a BP neural network and optimizing them using a genetic algorithm; wherein the coupling coefficients include the coupling coefficients of velocity to pressure, temperature to pressure, and velocity to temperature; dividing the pure copper low-temperature zone, pure copper high-temperature zone, and small-section zone according to temperature range and product cross-section, and formulating decoupling rules.

7. The control method for a continuous extrusion device according to claim 3, characterized in that, Also includes: The raw material fluctuations and die wear during the continuous extrusion process of copper are detected, and the coupling / decoupling model and control parameters are dynamically corrected based on the detection results.

8. A continuous extrusion apparatus, using the control method for a continuous extrusion apparatus as described in any one of claims 1-7, characterized in that, The device includes a feeding device, an extrusion device, and a receiving device, which are sequentially arranged along the conveying direction of the copper rod. A cutting mechanism is closably installed at the copper rod input port of the extrusion device. A shoe seat mechanism and a clamping mechanism are installed at the copper rod output end of the extrusion device. The clamping mechanism includes a limiting module and a hydraulic unit. The shoe seat mechanism has a clamping state and an initial state. When the shoe seat mechanism switches from the initial state to the clamping state, a locking operation is performed on the shoe seat mechanism by the clamping mechanism, including: providing locking pressure to the shoe seat mechanism through the limiting module to mechanically lock the shoe seat mechanism, and providing energy storage pressure to the shoe seat mechanism through the hydraulic unit. The clamping circuit of the hydraulic unit is equipped with... The device is equipped with a hydraulic lock, and the hydraulic unit generates the energy storage pressure through the hydraulic lock; wherein, the energy storage pressure is a low pressure more than twice the actual working pressure, the locking pressure is a low pressure of 3-5 MPa, the energy storage pressure is a low pressure of 8-12 MPa, the locking pressure is equal to the actual working pressure, and the actual working pressure is determined based on the extrusion force generated by the extrusion wheel; the extrusion device is used to perform copper rod extrusion operation on the copper rod conveyed by the feeding device, and the finished product output by the extrusion device is received by the receiving device; wherein, during the copper rod extrusion operation, multi-source monitoring data of the extrusion device is acquired in real time, and the copper rod extrusion operation of the extrusion device is dynamically adjusted according to the multi-source monitoring data.

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