Automatic dynamic balance control system for quenching tank furnace pressure

Abstract

The invention relates to the field of quenching tanks, and discloses a quenching tank furnace pressure automatic dynamic balance control system which comprises a control system. A one-way valve mechanism; the one-way valve mechanism communicates with the quenching chamber; the one-way valve mechanism carries out rough adjustment and fine adjustment on the furnace pressure in the quenching chamber through a grading adjustment strategy; the pressure balance system communicates with the quenching chamber and is used for adjusting the furnace pressure in the quenching chamber under the normal working condition. A pressure relief system; the pressure release system communicates with the quenching chamber and is used for releasing the pressure in the quenching chamber when the adjustment of the mechanical one-way valve mechanism fails; a pressure sensor; the pressure sensor is arranged in the quenching chamber and is used for detecting the hearth pressure in the quenching chamber and feeding back pressure detection data to the control system; an APC multivariable control system; the control system receives control variables output by the APC multivariable control system and sends control instructions to the pressure balance system and the pressure release system. According to the technical scheme, the furnace pressure fluctuation range is smaller through the graded adjustment strategy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of quenching tank, in particular to a quenching tank furnace pressure automatic dynamic balance control system. BACKGROUND

[0002] The furnace pressure control of quenching tank is a key parameter in heat treatment process, and too high or too low will have a significant impact on equipment safety and product quality.

[0003] When the furnace pressure of quenching tank is too high, the high furnace pressure can cause the quenching oil in the tank to overflow from the sealing place, especially in the moment of workpiece immersion, the high-temperature oil is easy to cause fire when contacting open flame or heat source, thereby causing safety accidents; in addition, maintaining high pressure also needs more protective gas, resulting in rising operation cost.

[0004] When the furnace pressure of quenching tank is too low, the negative pressure or micro positive pressure is insufficient, and the external air is easy to penetrate into the furnace, which can mix with the combustible protective atmosphere (such as propane) and cause explosion danger; in addition, the air entering will destroy the stability of the atmosphere and affect the control accuracy of the atmosphere.

[0005] How to solve this technical problem is a technical problem that needs to be overcome by those skilled in the art. SUMMARY

[0006] The embodiment of the present application provides a quenching tank furnace pressure automatic dynamic balance control system to at least partially solve the above technical problems.

[0007] In order to achieve the above purpose, according to the first aspect of the present application, a quenching tank furnace pressure automatic dynamic balance control system is provided, comprising:

[0008] A control system;

[0009] A one-way valve mechanism; the one-way valve mechanism is communicated with the quenching chamber; the one-way valve mechanism coarsely adjusts and finely adjusts the furnace pressure in the quenching chamber through a staged adjustment strategy;

[0010] A pressure balance system; the pressure balance system is communicated with the quenching chamber, and is used for adjusting the furnace pressure in the quenching chamber under normal working conditions;

[0011] A pressure release system; the pressure release system is communicated with the quenching chamber, and is used for releasing the pressure in the quenching chamber when the mechanical one-way valve mechanism fails to adjust;

[0012] A pressure sensor; the pressure sensor is arranged in the quenching chamber, and is used for detecting the furnace pressure in the quenching chamber and feeding back the pressure detection data to the control system;

[0013] An APC multivariable control system is provided, wherein an APC multivariable prediction model is deployed in the APC multivariable control system, the APC multivariable control system receives quenching information and pressure detection data fed back by the control system, the APC multivariable prediction model adjusts parameters of the prediction model based on the received quenching information and pressure detection data, and sends the adjusted parameters to the APC multivariable control system, and the APC multivariable control system outputs control variables of the pressure balance system and the pressure release system to the control system based on the adjusted parameters.

[0014] The control system receives the control variables output by the APC multivariable control system and sends control instructions to the pressure balance system and the pressure release system.

[0015] Optionally, the one-way valve mechanism comprises a pressure adjusting block, a one-way valve plate guide sleeve, a one-way valve guide rod, and a one-way valve plate. The one-way valve plate guide sleeve is fixedly arranged, the one-way valve guide rod is arranged in the one-way valve plate guide sleeve, the one-way valve plate is fixed to the one-way valve guide rod, and the one-way valve plate and the airflow medium passage of the quenching chamber form a sealing surface through the self-weight of the one-way valve plate.

[0016] The pressure adjusting block is arranged on the one-way valve guide rod to cooperate to realize fine adjustment of the furnace pressure.

[0017] When the fluctuation amplitude of the furnace pressure in the quenching chamber is greater than a first fluctuation amplitude, the airflow in the furnace pushes the one-way valve plate to open along the airflow medium passage, and the pressure is released through the airflow medium passage to realize coarse adjustment of the furnace pressure.

[0018] When the furnace pressure is in a steady state adjustment stage after coarse adjustment, the pressure adjusting block changes the overall balance pressure of the one-way valve mechanism by adjusting the position on the one-way valve guide rod to fine adjust and maintain the steady state of the furnace pressure.

[0019] Optionally, a hybrid self-learning is adopted, and the formula for the previous feedback correction is: wherein, is the time and duration parameter of the current opening; is the time and duration parameter of the previous opening; is the time and duration parameter of the previous two openings; is the previous opening feedback coefficient; is the set value of the pressure in the quenching tank; , is the average pressure deviation during the previous two opening and closing; and β is a filtering coefficient; is a dimension conversion coefficient for converting the dimension of pressure to the dimension of time;

[0020] The APC multivariable prediction model corrects the output parameters based on historical pressure detection data and quenching information through the front feedback correction formula, so that the control variables of the pressure balance system and the pressure release system output by the APC multivariable control system adapt to real-time furnace pressure fluctuations.

[0021] Optionally, the system adopts a hybrid control mode of a one-way valve mechanism and a PID intelligent algorithm; the PID algorithm is configured in the control system.

[0022] The APC multivariable prediction model optimizes the output pressure control target value through hybrid self-learning based on historical furnace pressure regulation data, real-time furnace pressure data fed back by a pressure sensor, and workpiece quenching information, and transmits the pressure control target value to the control system through the APC multivariable control system.

[0023] The control system receives the pressure control target value and calculates and generates a regulation signal through a PID algorithm combined with the deviation of real-time furnace pressure data and the target value and the mechanical dead zone compensation parameter output by the APC multivariable prediction model, and acts on the furnace pressure regulation through the pressure balance system; the mechanical dead zone compensation parameter is a pressure threshold deviation correction value of one-way valve plate action.

[0024] Optionally, the control system extracts furnace pressure cycle characteristics based on multiple sets of historical furnace pressure fluctuation data and real-time quenching process parameters to generate a parameter library containing peak cycle, micro-fluctuation cycle, peak intensity, and decay coefficient, and stores the parameter library in a cache module of the control system; the control system further comprises an intermittent regulation execution unit.

[0025] The APC multivariable prediction model processes the current furnace pressure data fed back by the pressure sensor, extracts real-time fluctuation cycle, instantaneous intensity, and trend decay characteristics, and compares them with historical characteristics in the cycle characteristic parameter library to calculate the cycle matching degree.

[0026] The intermittent regulation execution unit receives the cycle matching result of the APC multivariable prediction model and outputs a hierarchical instruction to the pressure balance system; when the furnace pressure deviation is in the micro-fluctuation range and the duration exceeds a preset duration, the regulation interval is extended; a preset duration before the predicted peak, the control valve of the pressure balance system is pre-opened to a preset proportion of the target opening degree.

[0027] The PID parameter dynamic adaptation unit is built-in with a dynamic weight factor K; when the furnace pressure deviation is less than a preset deviation threshold and the trend is stable, the weight factor K is adjusted to reduce the PID proportional gain and extend the integral time; when the furnace pressure deviation reaches or exceeds the preset deviation threshold or the APC multivariable prediction model predicts that a peak deviation will occur in the short term, the weight factor K is adjusted to increase the PID proportional gain and shorten the differential time.

[0028] Optionally, the front opening feedback coefficient K and the filter coefficient β in the front feedback correction formula are initialized according to the quenching process type.

[0029] Optionally, the pressure balancing system comprises a plurality of regulating valves arranged in parallel, each regulating valve corresponding to a different regulating flow level.

[0030] The control system selects the regulating valve of the corresponding level to be opened according to the control variable output by the APC multivariable control system.

[0031] Optionally, the mechanical dead zone compensation parameter is updated by the APC multivariable prediction model according to historical regulating data, and the update period is synchronized with the workpiece quenching batch.

[0032] After each workpiece quenching is completed, the APC multivariable prediction model calculates the deviation between the actual opening pressure of the one-way valve and the theoretical value in the current regulating process, and takes the average deviation as the dead zone compensation initial value for the next regulation.

[0033] Compared with the prior art, the furnace pressure fluctuation range is smaller, and the furnace pressure stability is greatly improved by the hierarchical regulating strategy.

[0034] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0036] Figure 1 is a schematic diagram of a one-way valve mechanism provided in an exemplary embodiment of the present application;

[0037] Figure 2 is a system schematic diagram of a quenching tank furnace pressure automatic dynamic balancing control system provided in an exemplary embodiment of the present application;

[0038] Figure 3 is a system control logic provided in an exemplary embodiment of the present application;

[0039] Legend of reference signs: 1, pressure adjusting block; 2, one-way valve plate guide sleeve; 3, one-way valve guide rod; 4, one-way valve plate; 5, gas medium passage; 6, mechanical one-way valve mechanism; 7, quenching chamber; 8, pressure balancing system; 9, pressure release system; 10, pressure sensor; 11, furnace pressure; 12, APC multivariable control system; 13, APC multivariable prediction model; 14, control system. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort fall within the protection scope of the present application.

[0041] The existing furnace pressure control mode adopts a mechanical one-way valve structure or an automatic valve control (PID control) mode. The mechanical one-way valve structure has defects in sealing structure, and the sealing surface is difficult to process, has high cost and complex process, especially the sealing surface at the bottom of the conical valve seat hole is more difficult to control. Moreover, it is sensitive to impurities and particulate matter in the fluid, and the balance mass changes over time, causing the furnace pressure to rise. The sealing form has low reliability, and in addition, the hard seal wears: the metal valve core and valve seat are prone to scratches after multiple collisions, and long-term use causes leakage.

[0042] The automatic valve control (PID control) mode has the following main disadvantages in furnace pressure control. The PID control has obvious hysteresis in response to changes in furnace pressure, which can be eliminated by integral hysteresis effect, but also delays the response speed. In addition, the control mode has weak anti-interference ability, and the fluctuation is large under large disturbance. The PID has limited adjustment capacity when there is a large disturbance (furnace pressure mutation > 20 kPa), and the control system output saturates slowly after recovery in this state, which exacerbates the instability of the control system.

[0043] The present application provides a quenching tank furnace pressure automatic dynamic balance control system, please refer to Figure 1 The quenching tank furnace pressure automatic dynamic balance control system provided by the embodiments of the present application comprises:

[0044] a control system;

[0045] a one-way valve mechanism; the one-way valve mechanism is connected to the quenching chamber; the one-way valve mechanism coarsely adjusts and finely adjusts the furnace pressure in the quenching chamber through a staged adjustment strategy;

[0046] a pressure balance system; the pressure balance system is connected to the quenching chamber and is used to adjust the furnace pressure in the quenching chamber under normal working conditions;

[0047] a pressure release system; the pressure release system is connected to the quenching chamber and is used to release the pressure in the quenching chamber when the mechanical one-way valve mechanism fails to adjust;

[0048] a pressure sensor; the pressure sensor is arranged in the quenching chamber and is used to detect the furnace pressure in the quenching chamber and feed back the pressure detection data to the control system;

[0049] The APC multivariable control system is provided with an APC multivariable prediction model; the quenching information and pressure detection data fed back by the control system are received by the APC multivariable control system; the APC multivariable prediction model adjusts the parameters of the prediction model based on the received quenching information and pressure detection data, and sends the adjusted parameters to the APC multivariable control system; and the APC multivariable control system outputs the control variables of the pressure balance system and the pressure release system to the control system based on the adjusted parameters.

[0050] The control system receives the control variables output by the APC multivariable control system, and sends control instructions to the pressure balance system and the pressure release system.

[0051] Specifically, the pressure sensor detects the furnace pressure in the sealed quenching chamber in real time, and continuously feeds back the pressure detection data to the control system. When the pressure in the quenching chamber fluctuates, the one-way valve mechanism first starts the staged regulation strategy: if the furnace pressure fluctuates greatly, the one-way valve plate moves along the one-way valve guide rod under the action of the air flow thrust, quickly releases the pressure by opening the air flow medium channel, and smooths the large fluctuation; on the basis of coarse adjustment, the pressure adjusting block further finely adjusts the opening of the air flow channel to maintain the steady state of the furnace pressure.

[0052] Each time a workpiece is quenched, the control system feeds back the quenching information to the APC multivariable prediction model. The model dynamically adjusts the model parameters based on the received quenching information and historical pressure data fed back by the pressure sensor, optimizes the opening time and duration of the pressure balance system, and feeds back the parameters to the APC multivariable control system. The APC multivariable control system outputs control variables to the control system based on the optimized parameters, and the latter sends instructions to the pressure balance system to achieve precise regulation of the furnace pressure under normal working conditions; the control variables mentioned above are, for example, valve opening, running duration.

[0053] If the pressure in the quenching chamber continues to rise due to failure of the one-way valve mechanism or sudden disturbance, the pressure sensor detects the abnormal pressure and feeds back the data to the control system; the control system immediately starts the pressure release system to release the pressure by forcibly opening a larger flow channel, avoiding safety accidents caused by excessively high furnace pressure; the mechanical one-way valve mechanism provides physical level anti-backflow protection and automatically locks when the control system fails, preventing reverse flow of the medium.

[0054] The existing mechanical one-way valve has defects in the sealing structure, the sealing surface is difficult to process, is easily affected by impurities to change the counterweight, and has problems such as hard seal wear and leakage, resulting in large fluctuations in furnace pressure. The present scheme solves the problems of large fluctuation range and low sealing reliability of traditional mechanical valves by using the staged regulation strategy of the one-way valve mechanism, which quickly smooths large fluctuations by using the one-way valve plate and finely maintains the steady state by using the pressure adjusting block.

[0055] The existing automatic valve PID control has problems such as response lag, weak anti-interference, severe fluctuation under large disturbance, limited regulation capacity, slow recovery after output saturation, etc. The scheme uses a mechanical one-way valve + PID intelligent algorithm (self-learning / APC) hybrid control: the mechanical structure forcibly limits the flow mutation when the PID overshoots or oscillates, reducing the risk of loss of control; the APC self-learning algorithm compensates for the dead zone of the one-way valve in real time, reducing the lag effect; the APC optimized set value reduces the wear and tear of the one-way valve due to frequent operation, solving the problems of traditional PID lag and weak anti-interference.

[0056] By sampling the scheme of the present application, the furnace pressure fluctuation range is smaller, and the furnace pressure stability is greatly improved; in the hybrid control mode, the mechanical structure quickly responds to large fluctuations, and the APC self-learning algorithm compensates for the lag effect, so that the system can still be stably regulated when the furnace pressure suddenly changes, avoiding the slow recovery problem of traditional PID saturation; the physical locking function of the mechanical one-way valve and the emergency start of the pressure release system (i.e. the pressure balance system and the pressure release system) effectively avoid safety accidents such as quenching oil overflow fire caused by excessive furnace pressure and air infiltration explosion caused by low furnace pressure; the APC optimized set value reduces the frequent operation of the one-way valve, prolongs the mechanical life, and reduces the equipment maintenance cost.

[0057] In some embodiments, the one-way valve mechanism comprises: a pressure adjusting block, a one-way valve plate guide sleeve, a one-way valve guide rod, and a one-way valve plate; wherein the one-way valve plate guide sleeve is fixedly arranged, the one-way valve guide rod is arranged in the one-way valve plate guide sleeve, the one-way valve plate is fixed on the one-way valve guide rod, and the one-way valve plate and the airflow medium passage of the quenching chamber form a sealing fit surface through the self-weight of the one-way valve plate;

[0058] The pressure adjusting block is arranged on the one-way valve guide rod to cooperate to realize fine adjustment of the furnace pressure;

[0059] When the fluctuation amplitude of the furnace pressure in the quenching chamber is greater than a first fluctuation amplitude, the airflow in the furnace pushes the one-way valve plate to open along the airflow medium passage, and releases pressure through the airflow medium passage to realize coarse adjustment of the furnace pressure;

[0060] When the furnace pressure is in a steady state regulation stage after coarse adjustment, the pressure adjusting block changes the overall balance pressure of the one-way valve mechanism by adjusting the position on the one-way valve guide rod to fine tune the furnace pressure and maintain a steady state.

[0061] Specifically, the one-way valve mechanism comprises a pressure adjusting block, a one-way valve plate guide sleeve, a one-way valve guide rod and a one-way valve plate; the one-way valve plate guide sleeve is a fixed guide structure for providing stable sliding guide for the one-way valve guide rod; the one-way valve guide rod is axially arranged in the one-way valve plate guide sleeve and can be flexibly moved along the axial direction of the guide sleeve to ensure the stability of the movement track of the one-way valve plate; the one-way valve plate is fixedly connected to the end of the one-way valve guide rod and cooperates with the port of the gas flow medium channel of the quenching chamber; in the initial state, the one-way valve plate is tightly attached to the port of the gas flow medium channel by its own gravity to form a relatively sealed cooperation surface, thereby blocking the flow of the gas flow medium channel.

[0062] The pressure adjusting block is arranged on the one-way valve guide rod and its position can be adjusted along the axial direction of the one-way valve guide rod; by changing the relative position of the pressure adjusting block and the one-way valve plate, the balance pressure threshold of the whole one-way valve mechanism can be adjusted.

[0063] In the actual working process, the one-way valve mechanism realizes the furnace pressure control through the hierarchical adjustment strategy of coarse adjustment plus fine adjustment; when the furnace pressure in the quenching chamber fluctuates greatly due to the change of working conditions and the fluctuation amplitude is greater than the preset first fluctuation amplitude, the high-pressure gas flow in the furnace applies a pushing force to the one-way valve plate along the gas flow medium channel. When the pushing force is greater than the combined force of the self-weight of the one-way valve plate and the initial counterweight of the pressure adjusting block, the gas flow pushes the one-way valve plate to drive the one-way valve guide rod to move upward along the one-way valve plate guide sleeve, so that the sealing cooperation surface of the one-way valve plate and the gas flow medium channel is separated, the gas flow is quickly discharged through the gas flow medium channel, and the coarse adjustment of the furnace pressure is realized to quickly and smoothly reduce the large pressure fluctuation.

[0064] When the furnace pressure enters the steady state adjustment stage after the coarse adjustment, i.e. the fluctuation amplitude of the furnace pressure is less than the first fluctuation amplitude, the pressure adjusting block starts to play a fine adjustment role: by adjusting the fixed position of the pressure adjusting block on the one-way valve guide rod, the balance pressure of the whole one-way valve mechanism is changed to stabilize the furnace pressure around the set value.

[0065] In some embodiments, a hybrid self-learning is adopted, and the formula for the previous feedback correction is: ; wherein, is the time and duration parameter of this time opening; is the time and duration parameter of the previous time opening; is the time and duration parameter of the previous two times opening; is the feedback coefficient of the previous opening; is the set value of the pressure in the quenching tank; , is the average pressure deviation when the previous two times opening and closing; β is the filtering coefficient; is the dimension conversion coefficient for converting the pressure dimension to the time dimension;

[0066] The APC multivariate prediction model corrects the output parameters based on historical pressure detection data and quenching information using the forward feedback correction formula, so that the control variables of the pressure balance system and pressure release system output by the APC multivariate control system are adapted to real-time furnace pressure fluctuations.

[0067] Specifically, each time a workpiece enters the quenching chamber for quenching, the control system feeds back real-time quenching information, such as the number of workpieces, material, initial temperature, and quenching time, to the APC multivariate prediction model; the pressure sensor continuously collects the actual furnace pressure data from the first two adjustment processes and calculates the average pressure deviation between the first two adjustments. and The APC multivariate prediction model, based on the above quenching information and historical pressure detection data, calculates by substituting the pre-feedback correction formula: First, through... Obtain the average of the parameters from the first two activations as a baseline reference; then... The correction term for the pressure deviation is calculated, where the larger the pressure deviation, the greater the adjustment of the correction term to the baseline reference value. To convert the pressure dimension to the time dimension, a dimension conversion coefficient β is used to reduce abnormal fluctuation interference; finally, the start time and duration parameters for this optimization are obtained. Corrected parameters The data is fed back to the APC multivariable control system, which outputs specific control variables for the pressure balancing system and pressure release system based on this parameter, such as valve opening angle and continuous operating time. These variables are then converted into execution commands by the control system. Through real-time iterative self-learning correction, the model can continuously accumulate the furnace pressure change patterns during the quenching process, ensuring that the control variables always adapt to real-time furnace pressure fluctuations. This effectively compensates for the lag effect of traditional PID control and reduces the impact of the dead zone of the one-way valve.

[0068] In some embodiments, the system employs a hybrid control mode combining a one-way valve mechanism and a PID intelligent algorithm; the PID algorithm is configured in the control system.

[0069] The APC multivariate prediction model is based on historical furnace pressure regulation data, real-time furnace pressure data fed back by pressure sensors, and workpiece quenching information. It optimizes the output pressure control target value through hybrid self-learning and transmits the pressure control target value to the control system via the APC multivariate control system.

[0070] The control system receives the pressure control target value and calculates and generates an adjustment signal by combining the deviation between the real-time furnace pressure data and the target value and the mechanical dead zone compensation parameter output by the APC multivariate prediction model using a PID algorithm. The adjustment signal is then applied to the furnace pressure through the pressure balance system. The mechanical dead zone compensation parameter is the pressure threshold deviation correction value for the one-way valve plate action.

[0071] Specifically, the pressure control target value generated by the APC multivariable prediction model is transmitted to the control system through the APC multivariable control system. After the control system receives the target value, it first calculates the deviation between the real-time furnace pressure data and the pressure control target value. The APC multivariable prediction model outputs a mechanical dead zone compensation parameter based on the action characteristics of the one-way valve mechanism in historical adjustment. The mechanical dead zone compensation parameter is a pressure threshold deviation correction value for the action of the one-way valve plate, which is used to correct the adjustment error caused by the inherent dead zone of the one-way valve mechanical structure.

[0072] In this application, the PID algorithm quickly responds to the current deviation through the proportional element, eliminates the long-term static deviation through the integral element, and predicts the deviation trend through the differential element. The mechanical dead zone compensation parameter corrects the adjustment signal of the PID output. For example, when the one-way valve plate needs higher pressure to open due to mechanical dead zone, the compensation parameter will appropriately amplify the adjustment signal to ensure that the valve plate accurately acts at the preset pressure threshold.

[0073] This hybrid control mode effectively solves the inherent defects of traditional single mechanical control or single PID control: the one-way valve mechanism provides basic adjustment guarantee for furnace pressure through physical structure, forcibly limits flow mutation when PID algorithm overshoots or oscillates, and reduces the risk of system out of control; and the PID intelligent algorithm combines the dynamic target value output by the APC multivariable prediction model and the mechanical dead zone compensation parameter, which can compensate for the dead zone effect and hysteresis characteristics of the one-way valve in real time, and avoid the problem of delayed adjustment caused by mechanical dead zone in traditional PID.

[0074] In some embodiments, the control system generates a parameter library containing peak period, micro-fluctuation period, peak intensity, and decay coefficient based on multiple sets of historical furnace pressure fluctuation data and real-time quenching process parameters, and stores it in the cache module of the control system; the control system further comprises an intermittent adjustment execution unit;

[0075] The APC multivariable prediction model processes the current furnace pressure data fed back by the pressure sensor, extracts real-time fluctuation period, instantaneous intensity, and trend decay characteristics, and compares them with historical characteristics in the periodic characteristic parameter library to calculate the period matching degree;

[0076] The intermittent adjustment execution unit receives the period matching result of the APC multivariable prediction model and outputs a staged instruction to the pressure balancing system; wherein when the furnace pressure deviation is in the micro-fluctuation range and the duration exceeds the preset duration, the adjustment interval is extended; and the control valve of the pressure balancing system is controlled to be pre-opened to a preset proportion of the target opening degree at a preset time before the predicted peak value.

[0077] The PID parameter dynamic adaptation unit is built-in dynamic weight factor K, when the furnace pressure deviation is less than the preset deviation threshold and the trend is stable, the weight factor K is adjusted to reduce the PID proportion gain and prolong the integral time; when the furnace pressure deviation reaches or exceeds the preset deviation threshold or the APC multivariate prediction model predicts that a peak deviation will occur in the short term, the weight factor K is adjusted to increase the PID proportion gain and shorten the differential time.

[0078] Specifically, by extracting periodic characteristics such as peak period and micro-fluctuation period based on historical furnace pressure fluctuation data and real-time quenching process parameters and establishing a parameter library, the APC multivariate prediction model can quickly compare the real-time fluctuation characteristics of the current furnace pressure with the historical characteristics, calculate the period matching degree, and realize the early prediction of the furnace pressure change trend; according to the period matching result, a hierarchical instruction is output: when the furnace pressure is in the micro-fluctuation range and continues to exceed the preset time, the adjustment interval is prolonged, which can avoid the frequent action of mechanical structures such as one-way valves caused by small fluctuations in traditional control, reduce mechanical wear, and prolong the service life of the equipment; the control valve is pre-opened to a preset proportion of the target opening degree before the predicted peak, which can quickly suppress fluctuations when the peak comes, avoid safety risks caused by excessively high peak pressure, and solve the problem of delayed response in traditional regulation when a peak occurs.

[0079] The PID parameter dynamic adaptation unit adjusts the PID parameters in real time through the dynamic weight factor K: when the furnace pressure deviation is small, the proportion gain is reduced and the integral time is prolonged, which can avoid the overshoot or oscillation caused by fixed parameters in traditional PID in steady state, and reduce the adjustment redundancy under small fluctuations; when the furnace pressure deviation is large or a peak is predicted to occur, the proportion gain is increased and the differential time is shortened, which can enhance the response speed and adjustment strength of PID to large disturbances, and solve the problems of insufficient adjustment capacity and severe fluctuations in traditional PID under large deviation or sudden peak.

[0080] In some embodiments, the front opening feedback coefficient K and the filtering coefficient β in the front feedback correction formula are initialized according to the quenching process type.

[0081] In some embodiments, the pressure balance system includes a plurality of adjustment valves arranged in parallel, each adjustment valve corresponding to a different adjustment flow level;

[0082] The control system selects the adjustment valve of the corresponding level to be opened according to the control variable output by the APC multivariate control system.

[0083] In some embodiments, the mechanical dead zone compensation parameter is updated by the APC multivariate prediction model according to historical adjustment data, and the update period is synchronized with the quenching batch of workpieces.

[0084] After quenching of each workpiece is completed, the APC multivariable prediction model calculates the deviation of the actual opening pressure of the one-way valve from the theoretical value in the current adjustment process, and takes the average of the deviation as the dead zone compensation initial value for the next adjustment.

[0085] It should be noted that the quenching tank furnace pressure automatic dynamic balance control system provided by the embodiment of the present application is used to execute all process steps of the quenching tank furnace pressure automatic dynamic balance control system of the above-mentioned embodiment, and the working principles and beneficial effects of the two are one-to-one corresponding, thus it is not repeated.

[0086] In the description of the present application, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0087] In the above-mentioned embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0088] The embodiments, implementation manners and related technical features of the present application can be combined, replaced with each other without conflict.

[0089] The above is only the preferred embodiment of the present application, and does not limit the present application in any form, but any simple modification, equivalent change and modification made according to the technical essence of the present application to the above-mentioned embodiment without departing from the technical solution content of the present application, still belongs to the scope of the technical solution of the present application.

Claims

1. A quench tank furnace pressure automatic dynamic balancing control system, characterized by, The system comprises: a control system; a one-way valve mechanism; the one-way valve mechanism is connected to the quenching chamber; the one-way valve mechanism coarsely and finely adjusts the furnace pressure in the quenching chamber through a hierarchical regulation strategy; a pressure balance system; the pressure balance system is connected to the quenching chamber and is used to adjust the furnace pressure in the quenching chamber under normal working conditions; a pressure release system; the pressure release system is connected to the quenching chamber and is used to release the pressure in the quenching chamber when the mechanical one-way valve mechanism fails to regulate; a pressure sensor; the pressure sensor is arranged in the quenching chamber and is used to detect the furnace pressure in the quenching chamber and feed back the pressure detection data to the control system; an APC multivariable control system; the APC multivariable control system is provided with an APC multivariable prediction model; the APC multivariable control system receives the quenching information and the pressure detection data fed back by the control system; the APC multivariable prediction model adjusts the parameters of the prediction model based on the received quenching information and pressure detection data and sends the adjusted parameters to the APC multivariable control system; the APC multivariable control system outputs the control variables of the pressure balance system and the pressure release system to the control system based on the adjusted parameters; wherein the control system receives the control variables output by the APC multivariable control system and sends control instructions to the pressure balance system and the pressure release system.

2. The system of claim 1, wherein, The one-way valve mechanism comprises a pressure adjusting block, a one-way valve plate guide sleeve, a one-way valve guide rod and a one-way valve plate; wherein the one-way valve plate guide sleeve is fixedly arranged, the one-way valve guide rod is arranged in the one-way valve plate guide sleeve, the one-way valve plate is fixed to the one-way valve guide rod, and the one-way valve plate and the airflow medium passage of the quenching chamber form a sealing fitting surface through the self-weight of the one-way valve plate; The pressure adjusting block is arranged on the one-way valve guide rod and is used to cooperate to finely adjust the furnace pressure; When the fluctuation amplitude of the furnace pressure in the quenching chamber is greater than a first fluctuation amplitude, the airflow in the furnace pushes the one-way valve plate to open along the airflow medium passage, releases the pressure through the airflow medium passage, so as to coarsely adjust the furnace pressure; When the furnace pressure is in a steady state regulation stage after coarse adjustment, the pressure adjusting block changes the overall balance pressure of the one-way valve mechanism by adjusting the position on the one-way valve guide rod, so as to finely adjust the furnace pressure and maintain the steady state.

3. The system of claim 2, wherein, The APC multivariate prediction model adopts a hybrid self-learning, and a front feedback correction formula thereof is: ; wherein, is a time and duration parameter of this time opening; is a time and duration parameter of the previous 1 time opening; is a time and duration parameter of the previous 2 time openings; is a previous opening feedback coefficient; is a quenching tank pressure setting value; , is an average pressure deviation of the previous two times of opening and closing; and β is a filtering coefficient; is a dimension conversion coefficient for converting the pressure dimension into the time dimension; The APC multivariable prediction model corrects the output parameters based on the historical pressure detection data and quenching information through the forward feedback correction formula, so that the control variables of the pressure balance system and the pressure release system output by the APC multivariable control system adapt to the real-time furnace pressure fluctuation.

4. The system of claim 3, wherein, The system adopts a hybrid control mode of the one-way valve mechanism and the PID intelligent algorithm; the PID algorithm is configured in the control system; The APC multivariable prediction model optimizes the pressure control target value through hybrid self-learning based on the historical furnace pressure regulation data, the real-time furnace pressure data fed back by the pressure sensor and the workpiece quenching information, and transmits the pressure control target value to the control system through the APC multivariable control system. The control system receives the pressure control target value and generates an adjustment signal by a PID algorithm combined with the deviation of real-time furnace pressure data and the target value and the mechanical dead zone compensation parameter calculated and output by the APC multivariable prediction model, and acts on the furnace pressure adjustment through the pressure balance system; the mechanical dead zone compensation parameter is a one-way valve plate action pressure threshold deviation correction value.

5. The system of claim 4, wherein, The control system extracts furnace pressure cycle characteristics based on multiple sets of historical furnace pressure fluctuation data and real-time quenching process parameters to generate a parameter library containing peak cycle, micro-fluctuation cycle, peak intensity, and decay coefficient and store in the cache module of the control system; the control system also includes an intermittent adjustment execution unit; The APC multivariable prediction model processes the current furnace pressure data fed back by the pressure sensor, extracts real-time fluctuation cycle, instantaneous intensity, and trend decay characteristics, and compares them with historical characteristics in the cycle characteristic parameter library to calculate the cycle matching degree; The intermittent adjustment execution unit receives the cycle matching result of the APC multivariable prediction model and outputs a hierarchical instruction to the pressure balance system; wherein when the furnace pressure deviation is in the micro-fluctuation range and the duration exceeds the preset duration, the adjustment interval is extended; and the adjustment valve of the pressure balance system is controlled to be pre-opened to a preset proportion of the target opening degree a preset duration before the predicted peak value; The PID parameter dynamic adaptation unit has a built-in dynamic weight factor K, which is adjusted to reduce the PID proportional gain and extend the integral time when the furnace pressure deviation is less than the preset deviation threshold and the trend is stable; and the weight factor K is adjusted to increase the PID proportional gain and shorten the differential time when the furnace pressure deviation reaches or exceeds the preset deviation threshold or the APC multivariable prediction model predicts that a peak deviation will occur in the short term.

6. The system of claim 5, wherein, The front opening feedback coefficient K and the filter coefficient β in the front feedback correction formula are initialized according to the quenching process type.

7. The system of claim 6, wherein, The pressure balance system includes a plurality of parallelly arranged adjustment valves, each of which corresponds to a different adjustment flow rate level; The control system selects the corresponding level of adjustment valve to be opened according to the control variable output by the APC multivariable control system.

8. The system of claim 7, wherein, The mechanical dead zone compensation parameter is updated by the APC multivariable prediction model according to historical adjustment data, and the update cycle is synchronized with the workpiece quenching batch; After each workpiece quenching is completed, the APC multivariable prediction model calculates the deviation between the actual opening pressure of the one-way valve and the theoretical value in the current adjustment process, and takes the average deviation as the dead zone compensation initial value for the next adjustment.

Images