A control method for automatic feeding of a sintering granulator bin

Abstract

This invention belongs to the field of sintering feed control technology, and particularly relates to a control method for automatic feeding of sintering pellet mill hoppers. The specific steps are as follows: Step S1: Set the total feed rate and the feeding ratio of each hopper; Step S2: Establish a correlation model between the rotational speed of the disc feeder and the actual feed rate; Step S3: Collect operating parameters in real time and calculate the actual feed rate of each hopper; Step S4: Implement closed-loop control based on a constant total feed rate; Step S5: Identify hopper faults based on the current of the feeding belt; Step S6: Perform dynamic parameter calibration and optimization. This method, by establishing a correlation model between the disc rotational speed and the feed rate, combined with closed-loop control logic, ensures a constant total feed rate and a stable feeding ratio in each hopper, effectively reducing the impact of feed rate fluctuations on pelleting quality. Based on the current changes of the feeding belt, combined with a time threshold, it achieves real-time identification and early warning of hopper faults and belt overload faults, preventing the escalation of faults and production interruptions.

Description

Technical Field

[0001] This invention belongs to the field of sintering feeding control technology, and particularly relates to a control method for automatic feeding of sintering granulator hopper. Background Technology

[0002] In the sintering production process of the steel industry, the pellet mill is the core equipment for the pretreatment of sintering raw materials. The stable operation of its feeding section directly affects the pelleting quality and the stability of subsequent sintering processes. Currently, when two pellet mills are running in the sintering area, their feeding sections are usually equipped with two small bins for buffering and distributing raw materials. The feeding of the two bins is switched back and forth by a reversible belt. Operators check the material level in the bins on-site, judge the material inventory in the bins, and manually unload the material to achieve alternating feeding between the two bins. The discharge from both bins is achieved by a frequency-controlled disc feeder. The feed rate is initially controlled by adjusting the disc speed. The disc feeder then transports the material to the pellet mill via a small belt. In existing design technologies, precise control and fault monitoring of silo feeding rely on physical detection instruments. Typically, level gauges (such as ultrasonic level gauges or radar level gauges) and weighing devices (such as load cells) are installed on the silo. The level gauges monitor the material level within the silo, and the weighing devices obtain the actual discharge volume to adjust the silo feed rate and prevent material shortages and overflows. Simultaneously, abnormal signals from the level gauges are used to determine if silo blockage (material clogging the silo outlet, preventing normal discharge) or other faults have occurred.

[0003] However, the sintering production site has a harsh environment with high levels of dust, steam, and vibration. Level gauges and weighing devices are exposed to this environment for extended periods, which can lead to large measurement errors, equipment damage, and high maintenance costs. Furthermore, some older sintering production lines lack interfaces for installing level gauges and weighing devices in their feeding silos, making retrofitting difficult and costly. In addition, the existing dual silos use reversible belts to switch between feeding and unloading, relying on manual checks of material levels. Manual judgment is susceptible to environmental influences, resulting in untimely unloading (material depletion or overflow) or premature unloading (material waste, frequent switching). Inappropriate unloading operations affect feeding continuity, granulation efficiency, and product quality, and can even cause production interruptions. Moreover, the working environment for operators is harsh, and the labor intensity is high. Summary of the Invention

[0004] The purpose of this invention is to provide a control method for automatic feeding of sintering granulator hopper, which solves the problems of existing technology relying on level gauges and weighing devices, manual judgment, and being susceptible to deviations due to environmental influences, as well as unreasonable material feeding operations.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A control method for automatic feeding of the sintering granulator hopper, the specific steps of which are as follows: Step S1: Set the total feed rate and the feed ratio for each compartment; Step S2: Establish a correlation model between the rotational speed of the disc feeder and the actual feeding rate; Step S3: Collect operating parameters in real time and calculate the actual feeding amount of each compartment; Step S4: Closed-loop control based on constant total feed rate; Step S5: Identify silo faults based on the current of the feed conveyor belt; Step S6: Dynamic calibration and optimization of parameters.

[0006] Preferably, the specific details of setting the total feed rate and the sub-compartment feed ratio in step S1 are as follows: According to the sintering production process requirements, the total feed rate Q (unit: t / h) of the feeding sections of the two pellet mills is set, and the feed ratios k1 and k2 of the first and second small bins are set according to the operating load of the two pellet mills, where k1+k2=1. The target feed rate Q1=Q×k1 of the first small bin and the target feed rate Q2=Q×k2 of the second small bin are determined. The input window for setting Q, k1, and k2 is edited on the computer operation screen.

[0007] Preferably, the specific details of step S2, establishing the correlation model between the rotational speed of the disc feeder and the actual feeding amount, are as follows: For each frequency converter-controlled disc feeder, a correlation model between the disc feeder's rotational speed and the actual feed rate was established through preliminary experimental calibration, as follows: Q n = C×r n Among them, Q n The actual feed rate of the disc feeder is expressed in t / h, and C is the calibration coefficient of the disc feeder, expressed in t / (h·r / min). C is determined by the structural parameters of the disc feeder (discharge port area, diameter at the midpoint of the discharge port on the disc surface, and speed ratio of the reducer) and the material characteristics (bulk density), i.e., C = A × γ × R × π × 60 / i, where A is the discharge port area of ​​the disc feeder, expressed in m². 2 γ is the bulk density of the material, in t / m³. 3 R is the diameter at the midpoint of the discharge port of the disc feeder, in meters; i is the speed ratio of the disc feeder reducer, which is fixed after preliminary testing and calibration; the rotational speed of the disc feeder is given by the main controller on the computer screen according to the sintering process. n The real-time rotational speed of the disc feeder is expressed in r / min.

[0008] Preferably, the specific details of step S3, which involves real-time acquisition of operating parameters and calculation of the actual feed rate of the compartments, are as follows: The following operating parameters are collected in real time by the control system, with a collection period of T (unit: s), and the value of T ranges from 1 to 5 s: (1) Real-time switching status of the reversible belt (corresponding to feeding the first small bin, feeding the second small bin, and stopping the machine); (2) The real-time rotational speed r1 of disc feeder #1 and the real-time rotational speed r2 of disc feeder #2; (3) Real-time operating current I1 of feed belt #1 and real-time operating current I2 of feed belt #2; Based on the correlation model established in step S2, the actual output of the first and second small bins is calculated respectively: Q1=C1×r1, Q2=C2×r2, where C1 is the calibration coefficient of the No.1 disc feeder and C2 is the calibration coefficient of the No.2 disc feeder. If the structural parameters and material characteristics of the two disc feeders are consistent, then C1=C2.

[0009] Preferably, the specific details of step S4, based on closed-loop control with a constant total feed rate, are as follows: (1) A control mode in which the rotation speed of two disc feeders is given on the computer screen, and the central control personnel set the frequency to feed according to the material consumption of the production process. The output amount is calculated according to the disc rotation speed in step S2. This mode is used when the sintering machine is first started. (2) In another control mode, when the total feed rate changes, in order to maintain the material balance in the two bins, the speed of the two disc feeders is adjusted, and the sum of the actual feed rates of the two bins, Q, is calculated. 实 =Q1+Q2, the actual total feed amount Q 实 With the set total feed rate Q 设 A comparison was conducted, and the rotational speeds of the two disc feeders were adjusted in a closed loop based on the comparison results to ensure a constant total feed rate. The specific control logic is as follows: If |Q 实 -Q 设 |≤ΔQ (ΔQ is the allowable deviation of the total feed rate. If the value range is 0.05~0.1t / h, then the rotation speed of the two disc feeders will remain unchanged.) If Q 实 -Q 设 If the value is greater than or equal to ΔQ, then according to the feeding ratio k, the speed of the two disc feeders is reduced simultaneously. The adjustment range Δr is proportional to the feeding deviation, i.e., Δr = β × (Q) 实 -Q 设 ), where β is the speed adjustment coefficient, in r / (min·t / h), until Q 实 Falling into [Q] 设 -ΔQ,Q 设 Within the range of +ΔQ; If Q 实 -Q 设 If the value is less than or equal to ΔQ, then the speeds of the two disc feeders are increased synchronously according to the feed ratio k, with an adjustment range Δr = β × (Q).实 -Q 设 ), where β is the speed adjustment coefficient, in r / (min·t / h), until Q 实 Falling into [Q] 设 -ΔQ, Q 设 Within the range of +ΔQ; At the same time, during the control process, ensure that the deviation between the actual feed rate and the target feed rate of a single hopper does not exceed ±5%, i.e., |Q 实 -Q 设 |≤0.05×Q 设 If the deviation of a single compartment exceeds the range, the speed of the corresponding disc feeder in that compartment should be adjusted first, and then the speed of the other compartment should be finely adjusted to ensure that the feeding ratio of each compartment is stable.

[0010] Preferably, the specific content of step S5, which identifies silo faults based on the current of the feeding conveyor belt, is as follows: By analyzing the real-time operating current of the feed conveyor belt and combining it with time parameters, the system can identify whether a hopper malfunction has occurred. The specific identification logic is as follows: (1) Through preliminary tests, the current range of each feed belt under normal feeding conditions was determined [I 小 I 大 ], where I 小 I is the minimum current during normal feeding. 大 The maximum current during normal feeding is set; simultaneously, a threshold t for the duration of abnormal current is set. 设 (Unit: s), t 设 The value range is 10~20s; (2) Monitor the current I1 of the first feeding belt and the current I2 of the second feeding belt in real time. If the current I of a certain feeding belt is... n 小 And the duration of this abnormal state is t n ≥t 设 If the feed conveyor belt corresponds to a bin with a malfunction (material blockage, unable to feed normally), then the actual feed rate Q of that bin is determined to be... 实 It approaches 0, resulting in a deviation from the calculated value; (3) If the current I of a certain feed belt is n >I 大 And the duration t n ≥t 设 If the feed belt is overloaded, accompanied by abnormal material feeding from the hopper (such as material clumping and uneven feeding), an early warning will be triggered simultaneously. ​(4) When a shed fault or overload fault is detected, the control system immediately issues an audible and visual alarm signal, and simultaneously records the time of the fault, the faulty shed number, current data, and disc rotation speed data to provide a basis for fault diagnosis; if the duration of the shed fault is t 棚 If the time exceeds 120 seconds, the corresponding disc feeder speed will be automatically reduced to the minimum value to prevent the equipment from running idle and causing damage. At the same time, the staff will be reminded to deal with the fault in time.

[0011] Preferably, the specific content of step S6, parameter dynamic calibration and optimization, is as follows: Every preset time t 预 , t 预 The value range is 2~4h. The calibration coefficients C1 and C2 of the disc feeder are dynamically calibrated. Specifically, under the premise of stable total feed rate, 10~15 minutes of data are collected on the disc rotation speed, feed belt current, and reversible belt switching status. Combined with minor changes in material characteristics, the calibration coefficient C is fine-tuned to ensure the accuracy of feed rate calculation. Simultaneously, based on changes in production load, the sub-compartment feeding ratios k1 and k2 are dynamically adjusted to ensure balanced load on the two pellet mills. Furthermore, combining historical feed rate data and reversible belt switching cycles, a "material consumption - remaining amount" calculation model is established to achieve fully automated control of the reversible belt automatic unloading process, as detailed below: (1) Preset basic parameters: Pre-enter the physical volume V1, V2 and the raw material bulk density ρ of the two small silos, and calculate the rated material quantity of the small silos: Rated material quantity = small silo volume × material bulk density, that is, the rated material quantity of the first small silo = V1 × ρ, and the rated material quantity of the second small silo = V2 × ρ. (2) Automatic material discharge threshold setting: Based on the rated material quantity of the small silo, the safety threshold for the remaining material quantity is set to 15%~20% of the rated volume, that is, the remaining material quantity threshold = (0.15~0.2) × the rated material quantity of the small silo, which is one of the trigger conditions for automatic feeding. If the material level of both small silos is lower than the safety threshold, the feeding of silo #1 is prioritized. The maximum threshold for the material quantity in the silo is set to 80%~90% of the rated volume, that is, the remaining material quantity threshold = (0.8~0.9) × the rated material quantity of the small silo, which is one of the trigger conditions for automatically stopping feeding and discharging material to the other small silo. The safety threshold and the maximum threshold are modified on the computer operation screen to meet the actual process requirements. (3) Setting the switching delay parameter: Set the switching delay t3. The value of t3 is 1~2s. It is dynamically fine-tuned according to the reversible belt model and material characteristics. It is used to eliminate the instantaneous deviation in the calculation of the remaining material amount, prevent accidental switching and sudden large current shutdown and motor burnout, and reserve time for reversible belt reversal and smooth material transition. (4) Automatic material feeding execution logic: The control system combines the real-time feeding amount of the current feeding bin (calculated by the disc rotation speed) and calculates the cumulative material consumption since the last feeding. It also calculates the remaining material amount in the bin in real time (remaining material amount = bin rated material amount - cumulative consumption). When the remaining material amount is lower than the preset threshold, the control system automatically triggers the reversible belt switching command. After stopping, it controls the reversible belt to change direction after a delay of t3, completes the automatic feeding and switches to another bin for feeding. If the cumulative amount in the feeding bin is greater than the bin's maximum threshold, the control system will also automatically trigger the reversible belt switching command to complete the feeding to another bin. No manual intervention is required throughout the process, avoiding untimely or premature feeding and ensuring a stable total feeding amount. The weight of the material in both bins is displayed on the computer screen, and the bins can be manually zeroed and the material amount can be entered.

[0012] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: (1) By establishing a correlation model between the disc rotation speed and the feed rate, and combining it with closed-loop control logic, the total feed rate is kept constant and the feed ratio of the compartments is kept stable, which effectively reduces the impact of feed rate fluctuations on granulation quality and improves the stability and consistency of sintering production. At the same time, the calibration coefficient is dynamically calibrated to adapt to the slight changes in material properties and further improve the accuracy of feed rate calculation. (2) Based on the current change of the feeding belt, combined with the time threshold, the real-time identification and early warning of shed faults and belt overload faults can be realized. It can detect abnormal feeding in time, avoid the fault from expanding and causing production interruption. At the same time, fault data is recorded to facilitate fault investigation. No additional detection probe is needed, which reduces the cost of fault detection. (3) No additional level gauge and weighing device are required. It is suitable for automatic material discharge of double small bin reversible belt. No manual operation is required. It utilizes the existing variable frequency disc feeder, feeding belt and reversible belt operating parameters, combined with the process logic of constant total feeding amount, to achieve precise control of feeding amount, real-time identification of bin failure and automatic material discharge of reversible belt, greatly reducing equipment investment and maintenance costs, while eliminating the operation deviation of manual material discharge. It is especially suitable for the transformation of old sintering production lines, solving the problems of traditional level gauge and weighing device being easily damaged and inaccurate in harsh environments, as well as low efficiency and large deviation of manual material discharge, avoiding complicated hardware transformation procedures. (4) The method has simple and reliable control logic, fast response speed, and is suitable for the harsh environment of sintering production site. It does not require complex algorithms and hardware support and is easy to promote and apply. At the same time, it supports manual adjustment and parameter optimization, taking into account the needs of automated control and manual intervention, and improving the flexibility and practicality of the system. Detailed Implementation

[0013] The technical solution of the present invention will be described in detail below with reference to the embodiments. Example 1

[0014] A control method for automatic feeding of the sintering granulator hopper, the specific steps of which are as follows: Step S1: Set the total feed rate and the feed ratio of each compartment. Based on the sintering production process requirements, the total feed rate Q of the two pellet mill feeding sections is set to 500 t / h. According to the operating load of the two pellet mills, the feed ratios k1 and k2 for the first and second small bins are set to 0.5 and 0.5 respectively, with k1 + k2 = 1. The target feed rate Q1 = Q × k1 for the first small bin and Q2 = Q × k2 for the second small bin are then determined. The input windows for Q, k1, and k2 are edited on the computer operation screen.

[0015] Step S2: Establish a correlation model between the rotational speed of the disc feeder and the actual feed rate. For each frequency converter-controlled disc feeder, a correlation model between the disc feeder's rotational speed and the actual feed rate was established through preliminary experimental calibration, as follows: Q n = C×r n Among them, Q n The actual feed rate of the disc feeder is expressed in t / h, and C is the calibration coefficient of the disc feeder, expressed in t / (h·r / min). C is determined by the structural parameters of the disc feeder (discharge port area, diameter at the midpoint of the discharge port on the disc surface, and speed ratio of the reducer) and the material characteristics (bulk density), i.e., C = A × γ × R × π × 60 / i, where A is the discharge port area of ​​the disc feeder, expressed in m². 2 γ is the bulk density of the material, in t / m³. 3 R is the diameter at the midpoint of the discharge port of the disc feeder, in meters (m); i is the speed ratio of the disc feeder reducer, which is fixed after preliminary testing and calibration. The rotational speed of the disc feeder is set by the main controller on the computer screen according to the sintering process. n The real-time rotational speed of the disc feeder is expressed in r / min.

[0016] Step S3: Collect operating parameters in real time and calculate the actual feed rate of each compartment. The following operating parameters are collected in real time by the control system, with a collection period of T (unit: s), and the value of T ranges from 1 s: (1) Real-time switching status of the reversible belt (corresponding to feeding the first small bin, feeding the second small bin, and stopping the machine); (2) The real-time rotational speed r1 of the No. 1 disc feeder is 10 r / min and the real-time rotational speed r2 of the No. 2 disc feeder is 10 r / min; (3) Real-time operating current I1 of feed belt #1 and real-time operating current I2 of feed belt #2; Based on the correlation model established in step S2, the actual output of the first and second small bins is calculated respectively. The structural parameters and material characteristics of the two disc feeders are consistent, so C1=C2. C1 is the calibration coefficient of disc feeder #1, with a value of 25t / (h·r / min), and C2 is the calibration coefficient of disc feeder #2, with a value of 25t / (h·r / min). Therefore, Q1=C1×r1=25×10=250t / h, and Q2=C2×r2=25×10=250t / h.

[0017] Step S4: Closed-loop control based on constant total feed rate (1) A control mode in which the rotation speed of two disc feeders is given on the computer screen, and the central control personnel set the frequency to feed according to the material consumption of the production process. The output amount is calculated according to the disc rotation speed in step S2. This mode is used when the sintering machine is first started. (2) In another control mode, when the total feed rate changes, in order to maintain the material balance in the two bins, the speed of the two disc feeders is adjusted, and the sum of the actual feed rates of the two bins, Q, is calculated. 实 =Q1+Q2=250+250=500t / h, the actual total feed rate Q 实 With the set total feed rate Q 设 A comparison was conducted, and the rotational speeds of the two disc feeders were adjusted in a closed loop based on the comparison results to ensure a constant total feed rate. The specific control logic is as follows: If |Q 实 -Q 设 If |≤ΔQ, where ΔQ is the allowable deviation of the total feed rate, and the value is 5t / h, then the rotation speed of the two disc feeders will remain unchanged. If Q 实 -Q 设 If the value is greater than or equal to ΔQ, then according to the feeding ratio k, the speed of the two disc feeders is reduced simultaneously. The adjustment range Δr is proportional to the feeding deviation, i.e., Δr = β × (Q) 实 -Q 设 ), where β is the speed adjustment coefficient, in r / (min·t / h), until Q 实 Falling into [Q] 设 -ΔQ,Q 设 Within the range of +ΔQ; If Q 实 -Q 设 If the value is less than or equal to ΔQ, then the speeds of the two disc feeders are increased synchronously according to the feed ratio k, with an adjustment range Δr = β × (Q). 实 -Q 设 ), where β is the speed adjustment coefficient, in r / (min·t / h), until Q 实 Falling into [Q] 设 -ΔQ, Q 设Within the range of +ΔQ; At the same time, during the control process, ensure that the deviation between the actual feed rate and the target feed rate of a single hopper does not exceed ±5%, i.e., |Q 实 -Q 设 |≤0.05×Q 设 If the deviation of a single compartment exceeds the range, the speed of the disc feeder corresponding to that compartment should be adjusted first, and then the speed of the other compartment should be finely adjusted to ensure the stable feeding ratio of the compartments. The computer operating screen can initialize the operating frequency of two given discs, and then automatically adjust it according to the feeding and discharging volume of the small hopper.

[0018] Step S5: Identify silo faults based on the current of the feed conveyor belt By analyzing the real-time operating current of the feed conveyor belt and combining it with time parameters, the system can identify whether a hopper malfunction has occurred. The specific identification logic is as follows: Through preliminary tests, the current range of each feed belt under normal feeding conditions was determined [I] 小 I 大 ], where I 小 The minimum current during normal feeding is set to 9A. 大 The maximum current during normal feeding is set to 18A, and a threshold value t for the duration of abnormal current is also set. 设 It lasts for 10 seconds. (2) Monitor the current I1 of the first feeding belt and the current I2 of the second feeding belt in real time. If the current I of a certain feeding belt is... n =8 小 And the duration of this abnormal state is t n =12≥t 设 If the feed conveyor belt corresponds to a bin with a malfunction (material blockage, unable to feed normally), then the actual feed rate Q of that bin is determined to be... 实 It approaches 0, resulting in a deviation from the calculated value; (3) If the current I of a certain feed belt is n =20>I 大 And the duration t n =11≥t 设 If the feed belt is overloaded, accompanied by abnormal material feeding from the hopper (such as material clumping and uneven feeding), an early warning will be triggered simultaneously. (4) When a shed fault or overload fault is detected, the control system immediately issues an audible and visual alarm signal, and simultaneously records the time of the fault, the faulty shed number, current data, and disc rotation speed data to provide a basis for fault diagnosis; if the duration of the shed fault is t 棚 If the time exceeds 60 seconds, the speed of the corresponding disc feeder will be automatically reduced to the minimum value to prevent the equipment from running idle and causing damage. At the same time, the staff will be reminded to deal with the fault in time.​

[0019] Step S6: Dynamic calibration and optimization of parameters Every preset time t 预 , t 预 The value is 2h. The calibration coefficients C1 and C2 of the disc feeder are dynamically calibrated. Specifically, under the premise of a stable total feed rate, 10-15 minutes of data are collected on the disc rotation speed, feed belt current, and reversible belt switching status. Combined with minor changes in material characteristics, the calibration coefficient C is fine-tuned to ensure the accuracy of the feed rate calculation. Simultaneously, the compartment feeding ratios k1 and k2 are dynamically adjusted according to changes in production load to ensure balanced load on the two pellet mills. Furthermore, based on historical feed rate data and the reversible belt switching cycle, a "material consumption - remaining amount" calculation model is established to achieve fully automated control of the reversible belt automatic unloading process, as detailed below: (1) Preset basic parameters: Pre-enter the physical volume of the two small compartments V1=16m 3 V2=16m 3 The specific gravity of the raw material pile is ρ = 1.9 tons / m³. 3 Calculate the rated material quantity of the small warehouse: Rated material quantity = warehouse volume × material bulk density, that is, the rated material quantity of the first small warehouse = V1 × ρ = 16 × 1.9 = 30 tons, and the rated material quantity of the second small warehouse = V2 × ρ = 16 × 1.9 = 30 tons. (2) Automatic material discharge threshold setting: Based on the rated material quantity of the small silo, the safety threshold for the remaining material quantity is set to 15% of the rated volume, that is, the remaining material quantity threshold = 0.15 × rated material quantity of the small silo = 0.15 × 30 = 4.5 tons, which is one of the trigger conditions for automatic feeding. If the material level of both small silos is lower than the safety threshold, the feeding of silo #1 is prioritized. The maximum threshold for the material quantity in the silo is set to 80% of the rated volume, that is, the maximum threshold = 0.8 × rated material quantity of the small silo = 0.8 × 30 = 24 tons, which is one of the trigger conditions for automatically stopping feeding and discharging material to the other small silo. The safety threshold and the maximum threshold are modified on the computer operation screen to meet the actual process requirements. (3) Setting the switching delay parameter: Set the switching delay t3, the value of t3 is 1s, and it is dynamically fine-tuned according to the reversible belt model and material characteristics. It is used to eliminate the instantaneous deviation in the calculation of the remaining material amount, prevent accidental switching and sudden large current shutdown and motor burnout, and reserve time for reversible belt reversal and smooth material transition. (4) Automatic material reloading logic: The control system combines the real-time feeding amount of the current feeding bin (calculated by the disc rotation speed) and calculates the cumulative material consumption since the last reloading. It also calculates the remaining material in the bin in real time (remaining material = bin rated material amount - cumulative consumption). When the remaining material in the first bin is 4.4 tons, which is lower than the preset threshold, the control system automatically triggers the reversible belt switching command. After stopping, it controls the reversible belt to change direction after a 1-second delay, completing the automatic reloading and switching to another bin for feeding. When the material in the first bin is 24.5 tons, which is greater than the bin's maximum threshold, the control system also automatically triggers the reversible belt switching command, completing the reloading to another bin. No manual intervention is required throughout the process, avoiding untimely or premature reloading and ensuring a stable total feeding amount. The weight of the material in both bins is displayed on the computer screen, and the bins can be manually zeroed and the material quantity can be entered manually.

[0020] After adopting this invention, the failure rate is reduced by 90%, the equipment investment cost is reduced by about 90,000 yuan, and there are no daily maintenance and spare parts costs, saving 20,000 yuan per year and reducing the annual labor cost by 180,000 yuan.

Claims

1. A control method for automatic feeding of the hopper in a sintering granulator, characterized in that, The specific steps are as follows: Step S1: Set the total feed rate and the feed ratio for each compartment; Step S2: Establish a correlation model between the rotational speed of the disc feeder and the actual feeding rate; Step S3: Collect operating parameters in real time and calculate the actual feeding amount of each compartment; Step S4: Closed-loop control based on constant total feed rate; Step S5: Identify silo faults based on the current of the feed conveyor belt; Step S6: Dynamic calibration and optimization of parameters.

2. The control method for automatic feeding of the sintering granulator hopper according to claim 1, characterized in that, The specific details of setting the total feed rate and the sub-compartment feed ratio in step S1 are as follows: According to the sintering production process requirements, the total feed rate Q (unit: t / h) of the feeding sections of the two pellet mills is set, and the feed ratios k1 and k2 of the first and second small bins are set according to the operating load of the two pellet mills, where k1+k2=1. The target feed rate Q1=Q×k1 of the first small bin and the target feed rate Q2=Q×k2 of the second small bin are determined. The input window for setting Q, k1, and k2 is edited on the computer operation screen.

3. The control method for automatic feeding of the sintering granulator hopper according to claim 2, characterized in that, The specific details of step S2, establishing the correlation model between the rotational speed of the disc feeder and the actual feeding amount, are as follows: For each frequency converter-controlled disc feeder, a correlation model between the disc feeder's rotational speed and the actual feed rate was established through preliminary experimental calibration, as follows: Q n = C×r n Among them, Q n The actual feed rate of the disc feeder is expressed in t / h, and C is the calibration coefficient of the disc feeder, expressed in t / (h·r / min). C is determined by the structural parameters of the disc feeder (discharge port area, diameter at the midpoint of the discharge port on the disc surface, and speed ratio of the reducer) and the material characteristics (bulk density), i.e., C = A × γ × R × π × 60 / i, where A is the discharge port area of ​​the disc feeder, expressed in m². 2 γ is the bulk density of the material, in t / m³. 3 R is the diameter at the midpoint of the discharge port of the disc feeder, in meters; i is the speed ratio of the disc feeder reducer, which is fixed after preliminary testing and calibration; the rotational speed of the disc feeder is given by the main controller on the computer screen according to the sintering process. n The real-time rotational speed of the disc feeder is expressed in r / min.

4. The control method for automatic feeding of the sintering granulator hopper according to claim 3, characterized in that, The specific details of step S3, which involves real-time acquisition of operating parameters and calculation of the actual feed rate of each compartment, are as follows: The following operating parameters are collected in real time by the control system, with a collection period of T (unit: s), and the value of T ranges from 1 to 5 s: (1) Real-time switching status of the reversible belt (corresponding to feeding the first small bin, feeding the second small bin, and stopping the machine); (2) The real-time rotational speed r1 of disc feeder #1 and the real-time rotational speed r2 of disc feeder #2; (3) Real-time operating current I1 of feed belt #1 and real-time operating current I2 of feed belt #2; Based on the correlation model established in step S2, the actual output of the first and second small bins is calculated respectively: Q1=C1×r1, Q2=C2×r2, where C1 is the calibration coefficient of the No.1 disc feeder and C2 is the calibration coefficient of the No.2 disc feeder. If the structural parameters and material characteristics of the two disc feeders are consistent, then C1=C2.

5. The control method for automatic feeding of the sintering granulator hopper according to claim 4, characterized in that, The specific details of step S4, based on closed-loop control with a constant total feed rate, are as follows: (1) A control mode in which the rotation speed of two disc feeders is given on the computer screen, and the central control personnel set the frequency to feed according to the material consumption of the production process. The output amount is calculated according to the disc rotation speed in step S2. This mode is used when the sintering machine is first started. (2) In another control mode, when the total feed rate changes, in order to maintain the material balance in the two bins, the speed of the two disc feeders is adjusted, and the sum of the actual feed rates of the two bins, Q, is calculated. 实 =Q1+Q2, the actual total feed amount Q 实 With the set total feed rate Q 设 A comparison was conducted, and the rotational speeds of the two disc feeders were adjusted in a closed loop based on the comparison results to ensure a constant total feed rate. The specific control logic is as follows: If |Q 实 -Q 设 If |≤ΔQ (ΔQ is the allowable deviation of the total feed rate, such as a value range of 0.05~0.1t / h), then the rotation speed of the two disc feeders will remain unchanged. If Q 实 -Q 设 If the value is greater than or equal to ΔQ, then according to the feeding ratio k, the speed of the two disc feeders is reduced simultaneously. The adjustment range Δr is proportional to the feeding deviation, i.e., Δr = β × (Q) 实 -Q 设 ), where β is the speed adjustment coefficient, in r / (min·t / h), until Q 实 Falling into [Q] 设 -ΔQ,Q 设 Within the range of +ΔQ; If Q 实 -Q 设 If the value is less than or equal to ΔQ, then the speeds of the two disc feeders are increased synchronously according to the feed ratio k, with an adjustment range Δr = β × (Q). 实 -Q 设 ), where β is the speed adjustment coefficient, in r / (min·t / h), until Q 实 Falling into [Q] 设 -ΔQ, Q 设 Within the range of +ΔQ; At the same time, during the control process, ensure that the deviation between the actual feed rate and the target feed rate of a single hopper does not exceed ±5%, i.e., |Q 实 -Q 设 |≤0.05×Q 设 If the deviation of a single compartment exceeds the range, the speed of the corresponding disc feeder in that compartment should be adjusted first, and then the speed of the other compartment should be finely adjusted to ensure that the feeding ratio of each compartment is stable.

6. The control method for automatic feeding of the sintering granulator hopper according to claim 5, characterized in that, The specific details of step S5, which identifies silo faults based on the current of the feeding conveyor belt, are as follows: By analyzing the real-time operating current of the feed conveyor belt and combining it with time parameters, the system can identify whether a hopper malfunction has occurred. The specific identification logic is as follows: (1) Through preliminary tests, the current range of each feed belt under normal feeding conditions was determined [I 小 I 大 ], where I 小 I is the minimum current during normal feeding. 大 The maximum current during normal feeding is set; simultaneously, a threshold t for the duration of abnormal current is set. 设 (Unit: s), t 设 The value range is 10~20s; (2) Monitor the current I1 of the first feeding belt and the current I2 of the second feeding belt in real time. If the current I of a certain feeding belt is... n 小 And the duration of this abnormal state is t n ≥t 设 If the feed conveyor belt corresponds to a bin with a malfunction (material blockage, unable to feed normally), then the actual feed rate Q of that bin is determined to be... 实 It approaches 0, resulting in a deviation from the calculated value;​ (3) If the current I of a certain feed belt is n >I 大 And the duration t n ≥t 设 If the feed belt is overloaded, accompanied by abnormal material feeding from the hopper (such as material clumping and uneven feeding), an early warning will be triggered simultaneously. (4) When a shed fault or overload fault is detected, the control system immediately issues an audible and visual alarm signal, and simultaneously records the time of the fault, the faulty shed number, current data, and disc rotation speed data to provide a basis for fault diagnosis; if the duration of the shed fault is t 棚 If the time exceeds 60 seconds, the speed of the corresponding disc feeder will be automatically reduced to the minimum value to prevent the equipment from running idle and causing damage. At the same time, the staff will be reminded to deal with the fault in time.

7. The control method for automatic feeding of the sintering granulator hopper according to claim 6, characterized in that, The specific details of step S6, parameter dynamic calibration and optimization, are as follows: Every preset time t 预 , t 预 The value range is 2~4h. The calibration coefficients C1 and C2 of the disc feeder are dynamically calibrated. Specifically, under the premise of stable total feed rate, 10~15 minutes of data are collected on the disc rotation speed, feed belt current, and reversible belt switching status. Combined with minor changes in material characteristics, the calibration coefficient C is fine-tuned to ensure the accuracy of feed rate calculation. Simultaneously, based on changes in production load, the sub-compartment feeding ratios k1 and k2 are dynamically adjusted to ensure balanced load on the two pellet mills. Furthermore, combining historical feed rate data and reversible belt switching cycles, a "material consumption - remaining amount" calculation model is established to achieve fully automated control of the reversible belt automatic unloading process, as detailed below: (1) Preset basic parameters: Pre-enter the physical volume V1, V2 and the raw material bulk density ρ of the two small silos, and calculate the rated material quantity of the small silos: Rated material quantity = small silo volume × material bulk density, that is, the rated material quantity of the first small silo = V1 × ρ, and the rated material quantity of the second small silo = V2 × ρ. (2) Automatic material discharge threshold setting: Based on the rated material quantity of the small silo, the safety threshold for the remaining material quantity is set to 15%~20% of the rated volume, that is, the remaining material quantity threshold = (0.15~0.2) × the rated material quantity of the small silo, which is one of the trigger conditions for automatic feeding. If the material level of both small silos is lower than the safety threshold, the feeding of silo #1 is prioritized. The maximum threshold for the material quantity in the silo is set to 80%~90% of the rated volume, that is, the remaining material quantity threshold = (0.8~0.9) × the rated material quantity of the small silo, which is one of the trigger conditions for automatically stopping feeding and discharging material to the other small silo. The safety threshold and the maximum threshold are modified on the computer operation screen to meet the actual process requirements. (3) Setting the switching delay parameter: Set the switching delay t3. The value of t3 is 1~2s. It is dynamically fine-tuned according to the reversible belt model and material characteristics. It is used to eliminate the instantaneous deviation in the calculation of the remaining material amount, prevent accidental switching and sudden large current shutdown and motor burnout, and reserve time for reversible belt reversal and smooth material transition. (4) Automatic material reloading execution logic: The control system combines the real-time feeding amount of the current feeding bin with the cumulative material consumption since the last reloading, and calculates the remaining material amount in the bin in real time. The remaining material amount = the rated material amount of the bin - the cumulative consumption. When the remaining material amount is lower than the preset threshold, the control system automatically triggers the reversible belt switching command, controls the reversible belt to change direction after a delay of t3, completes the automatic reloading and switches to another bin for feeding. If the cumulative amount in the feeding bin is greater than the maximum threshold of the bin, the control system will also automatically trigger the reversible belt switching command to complete the reloading to another bin. No manual intervention is required throughout the process, avoiding untimely or premature reloading, ensuring the stability of the total feeding amount, and displaying the material weight of the two bins on the computer screen. The bins can also be manually zeroed and the material amount can be entered manually.