Detailed explanation of operation and maintenance precautions for explosion-proof chain hoist

1、 Pre operation inspection: Ensure dual safety of equipment and environment

Equipment integrity check

Appearance inspection: Confirm that the shell has no cracks or deformations, and that the sealing gasket has not aged or fallen off, to prevent explosive gases or dust from entering the interior.

Component Tightness: Check whether all bolts and nuts are tightened to avoid component detachment or friction sparks caused by looseness.

Chain status: Check if the lifting chain is suspended vertically, without twisted links, and if the hook frame under the double row chain is not flipped. If the wear of the chain exceeds 10% of the original diameter, it needs to be replaced immediately.

Brake performance: Test whether the friction surface of the brake is clean and whether the braking is reliable. If the brake fails, it may cause heavy objects to fall off and lead to accidents.

Environmental adaptability check

Explosive area verification: Confirm the explosive gas/dust zoning of the workplace (such as Zone 1, Zone 2 or Zone 21, Zone 22), and select the corresponding explosion-proof level hoist (such as Ex d IIB T4).

Temperature group matching: Select the temperature group of the gourd based on the highest environmental temperature (such as T4 indicating surface temperature ≤ 135 ℃) to avoid explosions caused by high temperatures.

Corrosion protection: If the environment contains corrosive gases (such as hydrogen sulfide) or liquids, stainless steel shells or galvanized hoists should be selected, and anti rust oil should be regularly applied.

Load limit confirmation

Rated load identification: The gourd shell should be clearly marked with the rated load (such as 3 tons), and overloading is strictly prohibited. Overloading may cause chain breakage or shell deformation, damaging the explosion-proof structure.

Dynamic load test: Newly installed or repaired hoists must undergo a no-load test to confirm normal operation and reliable braking before they can be put into use.

2、 Standard operation: avoid risks caused by human errors

Control of lifting angle

Vertical lifting: Keep the chain suspended vertically to avoid a diagonal angle exceeding 5 °. Diagonal pulling may cause chain jamming, brake failure, and even rollover.

Zipper direction: When pulling the bracelet strip, the zipper direction should be in the same plane as the hand zipper wheel. It is strictly prohibited to pull the zipper diagonally to prevent chain jamming.

Operation force control

Uniform force: When pulling the bracelet, the force should be even and gentle, avoiding excessive force that may cause the bracelet to bounce or get stuck.

Exception handling: If the hand tension is found to be greater than the normal tension, the use should be stopped immediately, and the chain should be checked for jamming or overloading.

Personnel safety protection

Prohibited work below: During the lifting process, personnel are strictly prohibited from doing any work or walking under heavy objects to prevent them from falling and injuring people.

Operation position: The operator should stand in the same plane as the hand chain wheel and pull the hand chain to ensure smooth operation.

3、 Maintenance and upkeep: Extend equipment lifespan and ensure explosion-proof performance

Daily cleaning and lubrication

Cleaning requirements: After use, the gourd should be wiped clean to remove dust and stains, and to avoid residual corrosive substances.

Lubrication treatment: Regularly apply explosion-proof grease (such as lithium based grease) to components such as chains and bearings to reduce wear and delay rusting. During low temperatures in winter, it is necessary to heat the lubricating grease to ensure its fluidity.

Key component inspection

Friction pad inspection: Check the brake friction pads weekly. If oil stains or insufficient thickness are found, they should be replaced in a timely manner to prevent unstable braking.

Spring inspection: Regularly check the spring on the pawl. If the spring fails, it will cause the brake to malfunction and needs to be replaced immediately.

Rope inspection: During shift handover, check whether the ropes are worn, tangled, or twisted, whether the surface is clean, and whether the lubricating oil is sufficient.

Professional maintenance and scrapping

Regular maintenance: Conduct comprehensive maintenance at least once a year, including explosion-proof performance testing, load testing, etc., to ensure that the equipment meets the GB 3836 series standards.

Scrap condition: If the shell cracks, the chain wears out beyond the limit, or the brake fails and cannot be repaired, the equipment must be immediately scrapped.

4、 Personnel training and emergency response: enhancing safety awareness and skills

Operation training

Explosion proof knowledge: Operators need to understand the dangers of explosive environments, the explosion-proof principles and applicable scenarios of explosion-proof hoists.

Practical assessment: Regularly organize practical assessments to ensure that personnel master skills such as load calculation, lifting angle control, and braking testing, with a pass rate of 100%.

emergency drill

Fault simulation: Simulate scenarios such as chain breakage and brake failure, train personnel on how to emergency brake, evacuate personnel, and report.

Tool equipment: equipped with explosion-proof intercoms, emergency lighting and other devices to ensure the authenticity of the drill.

Warning signs and records

Identification requirements: Mark the explosion-proof level, rated load, and usage environment requirements in a prominent position on the gourd shell, and set up warning signs such as "No Overloading" and "No Striking".

Archive records: Establish inspection archives to record inspection dates, results, and repair contents for easy traceability and management.

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