Maintenance and upkeep guide for Explosion Proof Electric Hoist in explosive environments

To ensure the safe operation and extend the service life of electric hoists in explosive environments, a systematic maintenance and upkeep plan needs to be developed. The following provides detailed explanations from four aspects: daily inspection, regular maintenance, troubleshooting, and safety management:

1、 Daily inspection and operation standards

Pre operation inspection

Appearance inspection: Confirm that the shell is not deformed, cracked, or corroded, and that the fasteners are not loose.

Electrical system: Check whether the cables, plugs, and sockets are intact, without damage or aging.

Mechanical components: Confirm that the chain and wire rope are not worn, broken or deformed, the hook is not cracked or deformed, and the rotation is flexible.

Safety device: Test whether the limit switch, emergency stop button, and overload protection device are working properly.

Lubrication condition: Check whether the lubricating oil in the reducer, bearings and other parts is sufficient and there is no leakage.

Operating specifications

Load limit: Overloading is strictly prohibited to ensure that the load does not exceed the rated lifting capacity.

Smooth operation: Avoid sudden starts and stops, reduce mechanical impact.

Environmental monitoring: Confirm that the concentration of explosive gases or dust in the environment is within a safe range before operation.

Personnel protection: Operators are required to wear anti-static work clothes, safety helmets, protective gloves, etc.

2、 Regular maintenance and upkeep

Monthly maintenance

Cleaning: Remove dust and oil stains from the surface of the equipment, especially from electrical components and heat dissipation areas.

Tightening: Check and tighten all bolts and nuts to prevent loosening.

Lubrication: Lubricate the chain, wire rope, bearings, and other parts using lubricants that meet explosion-proof requirements.

Electrical testing: Use a megohmmeter to test the insulation resistance of the motor and control box, ensuring that it is not lower than the specified value (such as 0.5M Ω).

Quarterly maintenance

Comprehensive inspection: Disassemble some of the casing and check whether the internal electrical components and wiring terminals are loose or oxidized.

Functional testing: Simulate overload, limit and other faults to test the reliability of safety devices.

Chain/wire rope inspection: Measure the wear amount, and replace if it exceeds the specified value (such as chain wear reaching 10% of the original diameter).

Brake adjustment: Check the braking torque of the brake to ensure reliable braking.

Annual Maintenance

Overhaul: Disassemble equipment, clean and inspect all components, and replace severely worn parts.

Explosion proof performance testing: Entrust a professional organization to conduct explosion-proof performance testing to ensure compliance with standards (such as GB 3836).

Load test: Conduct a full load test in a safe environment to check the operation of the equipment.

Record archiving: Organize and maintain records, establish equipment archives, and provide a basis for subsequent maintenance.

3、 Common faults and troubleshooting methods

Possible causes and solutions for fault phenomena

Motor cannot start due to power failure, control circuit failure, or motor damage. Check the power and control circuits and replace damaged components

Suddenly stopping overload protection action during operation, triggering limit switch, reducing load due to electrical faults, resetting limit switch, checking electrical system

Brake failure, brake wear, improper adjustment, electrical malfunction. Replace brake pads, adjust brakes, and check electrical connections

Chain/wire rope breakage, overloading, severe wear, improper maintenance. Replace the chain/wire rope and strengthen daily inspections

Damage to explosion-proof casing caused by external impact, corrosion, aging, repair or replacement of casing, strengthening protective measures

4、 Safety management measures

staff training

Operators need to undergo professional training, familiarize themselves with equipment performance, operating procedures, and emergency response measures.

Regularly organize safety drills to improve emergency response capabilities.

Environmental management

Keep the work area clean and avoid the accumulation of explosive substances.

Install combustible gas/dust concentration monitoring devices to monitor environmental safety in real-time.

Spare parts Management

Reserve commonly used spare parts (such as chains, wire ropes, brake pads, etc.) to ensure timely replacement.

Spare parts must meet explosion-proof requirements and undergo regular quality checks.

Record and Trace

Establish a maintenance ledger to record the time, content, and replaced parts of each maintenance.

Conduct statistical analysis on equipment failures, identify high-frequency fault points, and take targeted measures.

5、 Precautions

Unauthorized modification is strictly prohibited: Do not change the electrical or mechanical structure of the equipment at will to avoid affecting its explosion-proof performance.

Use explosion-proof tools: During maintenance, explosion-proof tools should be used to avoid sparks.

Regular calibration: Regularly calibrate safety devices such as limit switches and overload protection devices to ensure their sensitivity and reliability.

Moisture and dust prevention: In damp or dusty environments, protective measures should be taken to prevent equipment from getting damp or accumulating dust.

The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist，Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment