Daily maintenance and maintenance methods of rotary automatic sandblasting machine

Guide to daily maintenance and maintenance of rotary automatic sandblasting machine

The stable operation of rotary automatic sandblasting machine depends on standard daily maintenance. Scientific maintenance can effectively prolong the service life of equipment, reduce the failure rate, ensure the stability of sandblasting process, and reduce energy consumption and consumables consumption. Following is a detailed description of the maintenance methods and matters needing attention from the daily, weekly, monthly and quarterly maintenance dimensions in combination with the practical standards of industrial surface treatment industry:

1. Daily maintenance (1 time before startup/1 time after shutdown, focusing on checking operation status and basic cleaning)

(1) Pre-startup inspection

Appearance and connection inspection: observe whether the equipment main body, rotary table, sandblasting gun group, pipeline and other parts are deformed or damaged; Check whether the anchor bolts and connecting bolts of components are loose, and focus on fastening bolts of key parts such as sandblasting gun rack, rotary table flange and dust collector base.

Electrical system inspection: open the electrical control cabinet, and check whether the indicator light and instrument display are normal, whether the cable terminal is loose and hot, and whether the inverter, contactor and other components are abnormal; Test whether the emergency stop button and safety interlock device are sensitive and reliable (the equipment cannot be started when the protective door is not closed).

Pneumatic system inspection: start the air source, confirm that the air pressure is stable at 0.6-0.8MPa, and check that there is no air leakage at the joints of the trachea, solenoid valve and cylinder; Observe the liquid level of the oil-water separator, timely discharge accumulated water and oil pollution, and ensure that the compressed air is dry and clean.

Inspection of sand material system: check the material level of the sand bin to ensure that the sand material is sufficient (not less than 1/3 of the bin volume), and check that the sand material is free of caking and large-particle impurities; Start the sand circulation system and observe whether the sand transportation is smooth and there is no pipe blockage.

Safety device inspection: confirm that the protective door is tightly closed and the dust detection alarm device and sound insulation facilities are normal; Wear personal protective equipment (PPE), including dust mask, protective glasses, sand control gloves and impact shoes.

(2) Maintenance after shutdown

Cleaning and arrangement: turn off the power supply and air supply, clean up the sand scattered on the surface and around the equipment, and use compressed air to purge the interior of the sandblasting room, the rotary table and the nozzle of the sandblasting gun to remove the residual sand and dust; Clean the dust hopper of the dust collector and transport the collected dust to the designated position in time (to avoid secondary dust).

Inspection and maintenance of parts: check the abrasion of the nozzle of the sandblasting gun, and replace it immediately if the abrasion exceeds 10% of the aperture (for example, the aperture of φ5mm nozzle is ≥5.5mm after abrasion) or cracks appear; Check whether the sandblasting pipe is damaged or aged, and whether the interface clamp is loose, and tighten or replace it if necessary.

Sand material treatment: screen the sand material in the sand bin, remove caking, large-particle impurities and metal chips, and replenish new sand to the specified material level (keep the grain size of sand material uniform); If the moisture content of sand is too high (> 2%), it needs to be dried or replaced with new sand.

Environmental maintenance: clean up the accumulated water and oil stains on the site and keep the ground flat and dry; Close the access door of sand bin and dust collector to prevent sundries from entering the equipment.

Second, the weekly maintenance (focus on checking the wearing parts and the running accuracy of the system)

Maintenance of slewing mechanism: rotate the slewing table manually, and check the flexibility of rotation, without jamming and abnormal sound; Remove the end cover of the workbench, add grease (choose lithium-based grease), and lubricate the meshing part between the bearing and the gear to ensure adequate lubrication; Check the sensitivity of the limit switch, adjust the limit stroke, and avoid the over-travel operation of the workbench.

Maintenance of sandblasting system: check the fixation of sandblasting gun group and adjust the angle and distance of sandblasting gun (keep an included angle of 30-60 and a distance of 100-200mm from the workpiece surface); Clean the sand separator, check whether the separation screen is blocked, and remove and clean it if necessary; Check the sensitivity of the sand replenishment device and the material level gauge to ensure that the alarm can be given in time when there is a shortage of sand.

Maintenance of the dust collector: disassemble the filter bag of the dust collector and use compressed air to reversely purge the dust on the surface of the filter bag (the pressure is controlled at 0.3-0.5MPa to avoid damaging the filter bag); Check whether the filter bag is damaged or aging, and replace it in time if there is a hole or the permeability decreases; Clean the pulse dust cleaning system of the dust collector, check whether the electromagnetic valve and the blowpipe work normally, and adjust the dust cleaning frequency (the dust is cleaned once every 30 minutes, which can be adjusted according to the dust concentration).

Deep maintenance of pneumatic system: remove oil-water separator and pressure reducing valve, clean internal filter element and valve body to remove oil and impurities; Check whether the cylinder seal is aging and leaking, and replace the sealing ring if necessary; Fill the pneumatic valve and solenoid valve with special lubricating oil to ensure smooth operation.

Electrical system maintenance: wipe the dust inside the electrical control cabinet with a dry rag, check whether the wiring terminals of electrical components are oxidized, and polish them with sandpaper and re-fasten them if necessary; Test the insulation of the motor (measured by megger, insulation resistance ≥1MΩ) to ensure that there is no short circuit risk.

Third, monthly maintenance (focusing on system calibration and component maintenance)

Equipment accuracy calibration: re-test the vertical and horizontal levelness of the equipment base with a level instrument, with an error of ≤0.2mm/m; if the deviation exceeds the standard, adjust the anchor bolt or shock absorber; Calibrate the rotating speed of the rotary table, and adjust it to the required rotating speed (5-20r/min) by frequency converter, with the rotating speed error ≤ 5%; Test the stability of sandblasting pressure and adjust the pressure reducing valve to ensure that the working pressure does not fluctuate within the range of 0.4-0.6MPa.

Comprehensive inspection of wearing parts: replace wearing parts such as sandblasting pipes, nozzles and sealing rings; Check whether the inner wall of sand silo and conveying pipeline is worn and corroded, and repair or replace it in time if the wall thickness becomes thinner or sand leaks; Check the bearing wear of the rotary table. If there is excessive clearance or abnormal sound, remove and replace the bearing.

Maintenance of sand circulation system: dismantle sand separator and screw conveyor, and clean up internal sand and impurities; Check the separation efficiency of the separator to ensure that unqualified sand (particle size > ＞1.2mm or < ＜0.1mm) can be effectively separated; Check the abrasion of the blades of the sand feed pump and replace the blades if necessary.

Maintenance of safety and environmental protection equipment: calibrate the dust concentration sensor to ensure accurate detection data, and give an alarm in time when the dust concentration exceeds 10 mg/m; Check the noise value of the equipment. If it exceeds 85dB, check whether the damping pad is aging and the equipment is loose, and install a sound insulation cover if necessary. Clean the drainage pipeline of the equipment to ensure the smooth discharge of sand blasting wastewater without blockage.

Maintenance of lubrication system: Fill all lubrication points of equipment (such as slewing mechanism, pump bearing and cylinder piston rod) with corresponding type of grease or lubricating oil; Check the oil level of lubricating oil. If it is lower than the specified scale, replenish it in time to ensure adequate lubrication of all moving parts.

Four, quarterly maintenance (focusing on in-depth maintenance and system optimization)

Disassembly inspection of equipment: Dismantle the sandblasting chamber door, rotary table, sandblasting gun group and other components, and thoroughly clean up the internal sand, dust and oil pollution; Check the abrasion of the abrasion-resistant lining board on the inner wall of sandblasting room, and replace it in time if the lining board becomes thinner (< 5 mm) or damaged; Check the gear and chain wear of the slewing mechanism. If the tooth surface is seriously worn or the chain is slack, replace or tighten it.

Deep overhaul of electrical system: check whether the output voltage and current of frequency converter are stable, and reset key parameters (such as upper limit of speed and overload protection threshold); Check the running temperature of the motor. If the motor casing temperature exceeds 75℃, check the bearing lubrication or the insulation of the motor winding, and repair the motor if necessary. Replace the aging cables and sensors to ensure the stability and reliability of the electrical system.

Comprehensive maintenance of pneumatic system: replace oil-water separator filter element and pressure reducing valve seal; Check the compressed air pipeline for aging and corrosion, and replace the pipeline if necessary; Test the running speed and stroke accuracy of the cylinder, and adjust the throttle valve to ensure the coordination of pneumatic components.

Process parameter optimization: according to the quarterly production data, analyze the sandblasting effect and equipment operation efficiency, and optimize the process parameters (such as sandblasting pressure, workbench speed and sandblasting time); Check the consumption of sand. If the consumption is too fast, check whether there is sand leakage or low separation efficiency, and adjust it in time.

Overall evaluation of equipment: summarize and analyze the running status of equipment, replacement records of wearing parts and fault handling, and formulate the maintenance plan for the next quarter; Check the equipment foundation for settlement and cracking. If there is any abnormality, reinforce the foundation in time.

V. Matters needing attention in maintenance

Safety operation specification: before maintenance, the power supply and gas supply of the equipment must be cut off, and the warning sign "Maintenance is under way, no starting" should be hung; Wear an anti-static bracelet when removing electrical components to avoid electrostatic damage to electronic components; Aerial work (such as repairing the top of the dust collector) needs to wear a safety belt to ensure the safety of the work.

Consumables and accessories management: choose the original factory or wearing parts that meet the equipment specifications (such as nozzles, filter bags and sealing rings) to avoid equipment failure caused by the use of non-standard accessories; Sand blasting media should be dry sand (such as quartz sand and brown corundum) with specified particle size, and it is forbidden to use sand containing metal impurities or moisture to avoid wearing equipment or affecting sand blasting effect.

Lubrication management: choose lubricating grease models (such as lithium-based grease and machine oil) strictly according to the requirements of the equipment manual, and avoid mixing different types of grease; Proper amount of grease should be added, too much will easily lead to overheating of parts, and too little will not play a lubricating role.

Recording and archiving: establish equipment maintenance ledger, and record the maintenance date, maintenance items, names and specifications of replacement parts, adjustment of process parameters, fault treatment results and other information in detail, so as to trace back the equipment operation status and maintenance history.

Personnel training requirements: maintenance personnel should receive professional training and be familiar with the equipment structure, working principle and maintenance process, and it is forbidden for unlicensed personnel to disassemble and repair the equipment without authorization; Regularly organize maintenance personnel to learn new technologies and methods of equipment maintenance, so as to improve the maintenance level.

By implementing the above hierarchical maintenance scheme, the failure rate of rotary automatic sandblasting machine can be effectively reduced, the service life of equipment core components (such as nozzles, bearings, motors, etc.) can be prolonged, the equipment can be kept in an efficient and stable running state for a long time, and reliable guarantee can be provided for industrial surface treatment technology.