Shot blasting machine and sand blasting machine grading dust removal anti-explosion cooperative control method dynamically adaptive to working conditions

Abstract

The invention provides a shot blasting machine and sand blasting machine grading dust removal anti-explosion cooperative control method dynamically adaptive to working conditions. According to the method, working condition parameters such as material hardness and loading capacity of a workpiece are collected in real time, a mapping model is established, and parameters such as the air inlet angle of a cyclone dust collector and the atomization pressure of a Venturi wet dust collector of the grading dust removal system are dynamically adjusted. And after graded dust removal, explosion-proof cooperative control is realized through a sensor arranged at the air inlet end of the Venturi dust remover, and two-stage control logic is executed. Meanwhile, the air volume transmitter is used for dynamically distributing the air volume of multiple devices, and the air speed and negative pressure are stable. In addition, a parameter self-correction mechanism is provided. According to the method, the working condition adaptability is deeply optimized, and the dust removal efficiency and energy consumption are balanced; a dedusting-explosion-proof collaborative closed loop is realized, and the safety risk is reduced; the multi-device cooperation efficiency is improved, and the operation and maintenance cost is reduced; and the system stability is continuously optimized, and the problem of dust treatment in combined operation of the shot blasting machine and the sand blasting machine in the prior art is effectively solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of industrial dust treatment and explosion-proof safety control, and particularly relates to a dust treatment method in a combined operation scene of a shot blasting machine and a sand blasting machine, and is especially suitable for dynamically adjusting dust removal parameters according to workpiece materials, load and other working conditions, realizing intelligent control of deep cooperation of grading purification and explosion-proof measures. BACKGROUND

[0002] The metal dust such as aluminum alloy and cast iron generated in the operation of the shot blasting machine and the sand blasting machine not only needs to meet the GB16297-1996 emission standard, but also needs to prevent explosion risk (the lower limit of aluminum alloy dust explosion is about 40g / m³). The existing technology has the following limitations: 1. Fixed dust removal parameters, poor adaptability The parameters such as the inlet air angle of the cyclone dust collector and the atomization pressure of the wet dust collector are fixed, and cannot match the working condition difference: when processing high-hardness workpieces, the dust concentration is more than 2000mg / m³, the coarse dust pretreatment efficiency is less than 70%, and the wet dust removal load increases sharply; when processing thin-walled parts, fine dust (≤0.5μm) is not captured enough, and the outlet concentration often exceeds 20mg / m³.

[0003] 2. Dust removal and explosion prevention are disconnected, and safety lags behind Explosion prevention only relies on a single concentration threshold (such as triggering explosion relief when the concentration is greater than 10g / m³), and is not linked with the dust removal state. When the atomization pressure drops sharply and the dust removal fails, the dust concentration can rise from 500mg / m³ to 1500mg / m³ within 30 seconds, and the explosion prevention trigger lags behind the risk formation.

[0004] 3. Lack of multi-device cooperation, energy consumption and safety imbalance When the shot blasting machine and the sand blasting machine share the dust removal system, the air volume distribution is fixed, and the start and stop of a single device can easily cause negative pressure fluctuation (±800Pa) to cause dust to escape; when the load is low, the fan still operates at the maximum air volume, and the energy consumption waste is up to 40%, and when the air speed is less than 23m / s, the dust deposits and needs to be cleaned frequently by manual operation.

[0005] Therefore, a control method capable of dynamically adapting to the working condition and realizing deep cooperation of dust removal and explosion prevention is needed to solve the above problems. SUMMARY

[0006] In view of the shortcomings of the prior art, the present application provides a shot blasting machine and sand blasting machine grading dust removal and explosion-proof cooperative control method with dynamic adaptation to working conditions, which solves the problems of fixed dust removal parameters of shot blasting machine and sand blasting machine, disconnection of dust removal and explosion prevention, lack of multi-device cooperation, high energy consumption and safety risk.

[0007] A shot blasting machine and sand blasting machine grading dust removal and explosion-proof cooperative control method with dynamic adaptation to working conditions, characterized in that it comprises the following steps: (1) Working condition parameter collection: Real-time acquisition of workpiece material hardness (180-260 HB) and single batch loading capacity (80-120 kg) of the shot blasting machine and the sand blasting machine, and establishment of a working condition-dedusting parameter mapping model; (2) Dynamic adjustment of dedusting parameters: Based on the working condition data of step (1), automatically adjust the parameters of the staged dedusting system: ① Inlet tangential angle of cyclone dust collector: 30° for high hardness / high load working conditions (hardness > 220 HB or loading capacity > 100 kg), and 20° for low hardness / low load working conditions; ② Atomization pressure of Venturi wet dust collector: 0.5 MPa for high concentration dust (> 1500 mg / m³), and 0.3 MPa for low concentration dust (< 800 mg / m³); (3) Staged dedusting execution: Pre-treat coarse dust (particle size > 10 μm) through the cyclone dust collector, with a pre-treatment efficiency of ≥ 85%, and then purify fine dust (particle size ≤ 10 μm) through the Venturi wet dust collector, with an outlet concentration of ≤ 10 mg / m³; (4) Explosion-proof cooperative control: Set dust concentration sensors (0-1000 mg / m³) and temperature sensors (-10-100 ℃) at the inlet of the Venturi dust collector, and implement two-level control logic: ① First warning: When the concentration is 500-1000 mg / m³, increase the atomization pressure to 0.4 MPa and increase the fan frequency to 55 Hz; ② Second interlock: When the concentration is > 1000 mg / m³ or the temperature is > 70 ℃, simultaneously trigger the shot blasting / sand blasting equipment to stop, open the explosion relief piece, and reduce the fan frequency to 40 Hz; (5) Dynamic distribution of air volume of multiple devices: Set an air volume transmitter at the intersection of the main air pipe of the shot blasting machine and the branch air pipe of the sand blasting machine, adjust the opening degree of the air volume distribution valve in real time, and ensure that the total air speed is always > 23 m / s and the system negative pressure is stable at -5000 Pa ± 300 Pa.

[0008] Preferably, the working condition parameter collection of step (1) also includes workpiece surface treatment area (m² / h), and when the treatment area is > 50 m² / h, it is automatically determined as a high load working condition.

[0009] Preferably, the atomization pressure adjustment of step (2) adopts PID closed-loop control, with an adjustment accuracy of 0.01 MPa and a response time of ≤ 5 seconds.

[0010] Preferably, the second interlock of step (4) also includes monitoring of the water level of the circulating water pool: when the liquid level is < 600 L, open the water replenishment valve until the liquid level returns to 80% (720 L) of the effective volume.

[0011] Preferably, the air volume distribution valve of step (5) adopts an electric adjustment mode, and when the shot blasting machine is operated alone, the opening degree is 75% (3000 m³ / h), and when the sand blasting machine is operated in cooperation, the opening degree is 25% (supplementing 1000 m³ / h), and the adjustment response time is ≤3 seconds.

[0012] Preferably, the parameter self-correction step is further included: every 24 hours of operation, the actual dust outlet concentration is compared with the preset threshold value, the cyclone inlet angle is corrected by ±1°, and the correction amplitude is not more than 5% of the initial value.

[0013] Preferably, the explosion-proof control of step (4) further includes static electricity monitoring: when the flange grounding resistance of the air pipe is greater than 100Ω, the fan speed is automatically reduced to 20 m / s, and the static electricity eliminator is started at the same time until the resistance is restored to be less than 100Ω.

[0014] The beneficial effects of the present application are as follows: 1. Deep optimization of working condition adaptability, balance of dust removal efficiency and energy consumption Through working condition-parameter dynamic mapping, the inlet angle of the cyclone dust collector is adjusted to 30° under high hardness / high load working conditions, the pretreatment efficiency of coarse dust (>10μm) is improved from 70% to 85%, the generation amount of wet dust slurry is reduced by 30%, and the mud scraping period is extended from 8 hours to 12 hours; under low load working conditions, the system pressure loss is reduced by 20%, and the fan energy consumption is reduced by 40% (12 degrees of power saving per shift). The fine dust (≤0.5μm) capture efficiency is improved to 99% by adjusting the Venturi atomization pressure, and the outlet concentration is stably controlled at ≤10 mg / m³, which is better than the GB16297-1996 standard (30 mg / m³), and is suitable for processing requirements of aluminum alloy, cast iron and other materials.

[0015] 2. Dust removal-explosion-proof closed loop, safety risk significantly reduced The first level warning adjusts the atomization pressure and fan frequency dynamically, and can intervene when the dust concentration is 500-1000 mg / m³, avoiding the concentration rising to the explosion threshold, and the explosion-proof response time is shortened from 30 seconds to 5 seconds; the secondary interlocking realizes the linkage of multiple parameters such as concentration, temperature and water level, and the water replenishment valve of the circulating water pool is opened synchronously after the explosion relief is triggered, preventing dry burning risk, and the interlocking failure rate is reduced by 60%. The dynamic reduction of the wind speed when the grounding resistance is abnormal reduces the risk of aluminum dust electrostatic ignition by 75%, which meets the explosion-proof standard of AQ4273-2016.

[0016] 3. Multi-device cooperation efficiency is improved, and the operation and maintenance cost is greatly reduced The air volume dynamic distribution makes the system negative pressure fluctuation narrow from ±800 Pa to ±300 Pa when the shot blasting machine and the sand blasting machine are combined, the dust escape amount is reduced by 90%, the workshop dust concentration is reduced from 2.5 mg / m3 to 0.8 mg / m3. The electric air volume valve responds quickly in 3 seconds, the air speed is always kept >23 m / s when the single device starts and stops, the pipeline dust cleaning period is extended from 8 hours to 24 hours, and the annual labor maintenance cost is reduced by 50,000 yuan. The fan intelligently adjusts the frequency according to the load, saves about 4380 degrees of electricity per year, and reduces the comprehensive operation cost by 35%.

[0017] 4. Parameter self-correction mechanism, continuous optimization of system stability The cyclone inlet angle is automatically corrected every 24 hours (±1°), ensuring that the pretreatment efficiency is long-term stable at 85%±2%; the electrostatic eliminator and the grounding resistor are linked to adjust, so that when the resistance exceeds the standard, the time is shortened from an average of 15 minutes per day to 3 minutes, the system fault-free operation time is extended from 120 hours to 300 hours, and the device comprehensive efficiency (OEE) is improved by 25%. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0019] Figure 1 The working condition adaptation and staged dust removal flowchart.

[0020] Figure 2 The staged dust removal-explosion-proof collaborative control flowchart. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0022] The present application will be described in detail below in combination with the mixed production line scene of processing aluminum alloy die castings (hardness 180-220 HB) and cast iron parts (hardness 260 HB). This embodiment is based on a KiC-200 type shot blasting machine and a SB-150 type sand blasting machine combined operation system, matched with a cyclone+Venturi staged dust removal device (model XLP / A-7.0+WD-6) and a Siemens S7-1200 PLC control system, and the specific implementation steps are as follows: I. System initialization configuration (I) Hardware deployment 1. Operating condition acquisition module: A workpiece hardness sensor (model TH110, measurement range 100-300 HB) is installed at the inlet of the shot blasting machine, with a sampling frequency of 1 Hz; a load sensor (model YZC-526, range 0-200 kg) is installed at the bottom of the sandblasting machine hopper, which outputs the batch load in real time.

[0023] 2. Dust removal parameter adjustment module: A cyclone dust collector inlet angle adjustment device (electric actuator model SM-10, adjustment range 15-35°); a Venturi wet dust collector atomization pressure regulating valve (model VP542, adjustment range 0.2-0.6 MPa, accuracy ±0.01 MPa).

[0024] 3. Explosion-proof and monitoring module: A dust concentration sensor (GCG1000, range 0-1000 mg / m³) is installed at the inlet of the Venturi; a temperature sensor (WZPB-S, range -10-100°C) is deployed at the same location as the concentration sensor; an explosion relief plate (model DB-80, nominal diameter 80 mm) is installed radially on the main air pipe, with the opening facing upwards; an air volume transmitter (WS-200EX, range 0-30 m / s) is installed at the intersection of the Φ300 main air pipe of the shot blasting machine and the Φ150 branch air pipe of the sandblasting machine.

[0025] 4. Control center: PLC connects all sensors and actuators through PROFINET bus, response time ≤50 ms.

[0026] (II) Basic parameter preset Enter the operating condition-parameter mapping table in the PLC:

[0027] Explosion-proof threshold setting: First level warning: concentration 500-1000 mg / m³ or temperature 60-70°C; Second level interlock: concentration >1000 mg / m³ or temperature >70°C; System negative pressure target value: -5000 Pa, allowable fluctuation ±300 Pa.

[0028] II. Operating condition dynamic adaptation and graded dust removal execution (I) Low load-aluminum alloy part processing (8:00-10:00) 1. Operating condition acquisition: The hardness sensor detects a value of 200 HB, and the load sensor feedbacks 90 kg / batch, and the PLC determines it as a "low load-aluminum alloy" operating condition.

[0029] 2. Parameter adjustment: The cyclone inlet angle was automatically adjusted to 20°, and the pressure difference before and after pretreatment was monitored by a differential pressure transmitter (model 3051CD) to be 1800 Pa (pressure loss reduced by 20%); the Venturi atomization pressure was adjusted to 0.3 MPa, and the circulating water pump (GPS-G-31-40) flow was stabilized at 15 m³ / h.

[0030] 3. Dust removal effect: The dust concentration at the outlet of the cyclone dust collector was detected to be 350 mg / m³ (pretreatment efficiency of coarse dust 82%), and the concentration at the outlet of the Venturi was 6 mg / m³ (≤10 mg / m³), meeting the emission standard.

[0031] (B) High load - cast iron processing (10:00-12:00) 1. Working condition switching: The hardness sensor jumped to 260 HB, the loading capacity increased to 110 kg / batch, and the PLC completed the working condition determination within 3 seconds, triggering parameter switching.

[0032] 2. Dynamic parameter adjustment: The cyclone inlet angle was adjusted from 20° to 30° by an electric actuator (adjustment time 4 seconds), and the pretreatment pressure difference increased to 2200 Pa; the atomization pressure increased from 0.3 MPa to 0.5 MPa, and the PLC used PID control (proportion coefficient 0.8, integral time 50 s), with a pressure overshoot of <5%.

[0033] 3. Dust removal effect: The cyclone outlet concentration decreased to 280 mg / m³ (pretreatment efficiency 85%), the Venturi outlet concentration was 8 mg / m³, the coarse dust capture increased by 30%, and the wet dust removal slurry production did not increase significantly.

[0034] Three, explosion-proof collaborative control example (A) First level early warning trigger and processing (11:15) 1. Abnormal detection: In the later stage of cast iron processing, the concentration sensor suddenly jumped to 800 mg / m³ (in the 500-1000 mg / m³ interval), and the temperature stabilized at 55°C.

[0035] 2. Linkage adjustment: PLC automatically executes: The Venturi atomization pressure increased from 0.5 MPa to 0.55 MPa (over the early warning threshold of 0.4 MPa); The fan frequency increased from 55 Hz to 58 Hz, and the air volume increased from 6600 m³ / h to 7000 m³ / h; After 30 seconds, the concentration fell to 600 mg / m³, and the system automatically returned to the original parameters without shutdown.

[0036] (II) Secondary interlock triggering and handling (14:30) 1. Emergency: A sudden failure of the circulating water pump caused the water pressure to drop from 0.5 MPa to 0.2 MPa, the concentration to rise to 1200 mg / m³ within 30 seconds, and the temperature to rise to 72°C, triggering the secondary interlock.

[0037] 2. Interlock action: The shot blasting machine / sand blasting machine feed valve was immediately closed (solenoid valve response time 0.5 seconds), and the equipment was shut down; the explosion vent was blown (action pressure 0.1 MPa), releasing the pressure in the pipe; the fan frequency was reduced to 40 Hz (air volume 4800 m³ / h), and at the same time the water supply valve (LR8000) was opened, and the circulating water pool level was raised from 550L to 720L (effective volume 80%) within 3 minutes.

[0038] 3. Recovery process: After the pump was repaired, the PLC detected that the water pressure returned to 0.5 MPa, the concentration dropped to 8 mg / m³, and the temperature was 50°C, and the sequence of "fan preheating for 5 minutes → parameter initialization → no-load operation for 10 minutes" was restarted, with a total recovery time of 25 minutes.

[0039] Four, dynamic allocation of air volume for multiple devices When the shot blasting machine runs alone at 15:00 and the sand blasting machine starts to work together at 15:30: 1. Shot blasting machine alone: The air volume transmitter detects the main air pipe wind speed of 25 m / s, and the PLC controls the air volume distribution valve opening degree of 75%, meeting the demand of 3000 m³ / h, and the negative pressure is stable at-4800 Pa.

[0040] 2. Sand blasting machine running together: After the sand blasting machine starts signal triggers, the air volume valve adjusts the opening degree from 75% to 25% within 3 seconds, the branch air pipe supplements 1000 m³ / h air volume, the total wind speed is maintained at 24 m / s, the negative pressure fluctuates to-5100 Pa (±300 Pa range), and no dust escapes.

[0041] Five, parameter self-correction and effect verification (I) Self-correction execution The system automatically executes parameter correction at 23:00 every day: Comparing the actual outlet concentration (6-8 mg / m³) with the preset threshold value (≤10 mg / m³), the cyclone inlet wind angle is fine-tuned from 30° to 29.5° (correction amplitude 1.7%<5%); The electrostatic grounding resistance detection value is 120Ω (>100Ω), the fan speed is automatically reduced to 20 m / s, and the electrostatic eliminator is turned on, after 5 minutes the resistance is reduced to 80Ω, and the original wind speed is restored.

[0042] (II) Implementation effect After the operation of the embodiment for 30 days, the key indicators are as follows: Dust removal efficiency: coarse dust pretreatment efficiency is stable at 85%±2%, outlet concentration is ≤10mg / m³, and the compliance rate is 100%; Safety performance: the success rate of first-level early warning intervention is 100%, the secondary interlock is triggered twice without accidents, and the explosion hazard is reduced by 75%; Energy consumption and maintenance: fan power saving is 4200 degrees per year, pipeline cleaning cycle is extended to 24 hours, and maintenance cost is reduced by 50,000 yuan per year; Device stability: system fault-free operation time is extended from 120 hours to 300 hours, and OEE is increased by 25%.

[0043] The above embodiment can be adapted to other materials (such as stainless steel) by adjusting the working condition-parameter mapping table, the control logic remains the same, and the same technical effect can be achieved.

[0044] The preferred embodiments disclosed above are only used to help explain the present application. The preferred embodiments do not describe all the details and limit the application to the specific embodiments described. Obviously, according to the content of the specification, many modifications and changes can be made. The specification selects and describes these embodiments in order to better explain the principles and practical applications of the application, so that those skilled in the art can well understand and use the application. The application is limited by the claims and their entire scope and equivalents.

Claims

1. A method for coordinated control of graded dust removal and explosion prevention in shot blasting and sandblasting machines with dynamic adaptation to working conditions, characterized in that, Includes the following steps: (1) Acquisition of working condition parameters: Real-time acquisition of workpiece material hardness (180-260HB) and single batch loading (80-120kg) of shot blasting machine and sandblasting machine, and establishment of working condition-dust removal parameter mapping model; (2) Dynamic adjustment of dust removal parameters: Based on the operating data in step (1), the parameters of the graded dust removal system are automatically adjusted: ①Cyclone dust collector inlet tangential angle: Adjust to 30° for high hardness / high load conditions (hardness > 220HB or load > 100kg), and adjust to 20° for low hardness / low load conditions; ② Venturi wet dust collector atomization pressure: adjust to 0.5MPa for high concentration dust (>1500mg / m³) and 0.3MPa for low concentration dust (<800mg / m³); (3) Graded dust removal: Coarse dust (particle size > 10μm) is pre-treated by a cyclone dust collector with a pre-treatment efficiency of ≥ 85%, and then fine dust (particle size ≤ 10μm) is purified by a Venturi wet dust collector with an outlet concentration of ≤ 10mg / m³. (4) Explosion-proof coordinated control: A dust concentration sensor (0-1000mg / m³) and a temperature sensor (-10-100℃) are installed at the air inlet of the Venturi dust collector to execute two-level control logic: ① Level 1 warning: When the concentration is 500-1000 mg / m³, increase the atomization pressure to 0.4 MPa and increase the fan frequency to 55 Hz; ② Level 2 interlock: When the concentration is >1000mg / m³ or the temperature is >70℃, the shot blasting / sandblasting equipment will be shut down, the explosion relief valve will be opened, and the fan frequency will be reduced to 40Hz. (5) Dynamic distribution of air volume for multiple devices: An air volume transmitter is installed at the intersection of the main air duct of the shot blasting machine and the branch air duct of the sandblasting machine to adjust the opening of the air volume distribution valve in real time, ensuring that the total air velocity is always >23m / s and the negative pressure of the system is stable at -5000Pa±300Pa.

2. The method according to claim 1, characterized in that, The acquisition of working condition parameters in step (1) also includes the surface treatment area of ​​the workpiece (m² / h). When the treatment area is greater than 50m² / h, it is automatically determined to be a high-load working condition.

3. The method according to claim 1, characterized in that, The atomization pressure adjustment in step (2) adopts PID closed-loop control with an adjustment accuracy of 0.01MPa and a response time of ≤5 seconds.

4. The method according to claim 1, characterized in that, The secondary interlock in step (4) also includes monitoring the water level in the circulating water tank: when the liquid level is <600L, the water supply valve is opened in conjunction until the liquid level is restored to 80% of the effective volume (720L).

5. The method according to claim 1, characterized in that, The air volume distribution valve in step (5) is electrically adjustable. When the shot blasting machine is running alone, the opening is 75% (3000m³ / h), and when the sandblasting machine is running in conjunction, the opening is 25% (supplementary 1000m³ / h). The adjustment response time is ≤3 seconds.

6. The method according to claim 1, characterized in that, It also includes a parameter self-correction step: every 24 hours of operation, the actual dust outlet concentration is compared with the preset threshold, and the cyclone inlet angle is corrected by ±1°, with the correction range not exceeding 5% of the initial value.

7. The method according to claim 1, characterized in that, The explosion-proof control in step (4) also includes electrostatic monitoring: when the grounding resistance of the duct flange is >100Ω, the fan speed is automatically reduced to 20m / s, and the electrostatic eliminator is turned on until the resistance is restored to <100Ω.

Images