To prevent fatigue and damage of manual hoists used on ships, comprehensive measures need to be taken from five aspects: design selection, operation specifications, maintenance, environmental control, and personnel management, to ensure the long-term reliable operation of equipment under special working conditions of ships. The following are specific measures:

1、 Design selection optimization

Material Upgrade

Corrosion resistance: Stainless steel or hot-dip galvanized materials are selected to resist corrosion from seawater and salt spray, extending the life of components such as chains and hooks.

High strength alloy: Key components such as gears and shafts are made of high-strength alloy steel to enhance fatigue resistance and reduce the risk of fracture.

structural optimization

Lightweight design: Reduce equipment weight, lower operator labor intensity, and minimize fatigue damage caused by frequent operations while ensuring strength.

Anti winding chain: using a special chain link structure (such as a flat chain) to reduce the risk of chain winding in complex spaces.

Upgrade of protection level

Sealing design: The gearbox, brake and other components adopt a sealing structure to prevent seawater and dust from entering and prevent internal corrosion.

Waterproof handle: A waterproof sleeve is added to the handle to prevent seawater splashing in during operation, which may cause a short circuit in the circuit (electric auxiliary type) or rust on the handle.

2、 Strengthening operational standards

Load control

Strict load limit: Mark the rated load in a prominent position on the equipment and equip it with overload protection devices (such as mechanical limiters) to prohibit overloading.

Dynamic monitoring: Check the load weight before operation to avoid overloading caused by estimation errors; Real time observation of the force on the chain during the lifting process.

Standardized operating techniques

Uniform lifting and lowering: Avoid sudden pulling and releasing, reduce chain impact load, and lower the risk of fatigue fracture.

Vertical lifting: Keep the angle between the chain and the vertical direction ≤ 30 ° to prevent equipment from being damaged due to lateral tension caused by unbalanced load.

Prohibit diagonal pulling: When the diagonal pulling angle exceeds the allowable value, immediately adjust the lifting direction to avoid chain distortion or gear jamming.

Homework frequency management

Rotation operation: When working continuously for a long time, arrange for operators to rotate to avoid operational errors caused by single person fatigue.

Intermittent rest: Take a 5-10 minute break every 30 minutes to relieve muscle fatigue and maintain operational accuracy.

3、 Institutionalization of maintenance and upkeep

routine inspection

Pre use inspection: Before operation, check whether the chain, hook, gear and other components are intact, whether the brake is sensitive, and whether the lubricating oil is sufficient.

Cleaning after use: Rinse the surface salt of the equipment with fresh water, wipe dry and apply rust proof oil to prevent corrosion.

regular maintenance

Monthly inspection: Disassemble and inspect the wear of internal components such as gears and bearings, replace lubricating oil, and adjust the brake clearance.

Annual maintenance: Entrust professional institutions to conduct comprehensive testing, including non-destructive testing (such as magnetic particle testing of chains), braking performance testing, etc.

Replacement of vulnerable parts

Chain replacement: When the diameter of the chain link is worn down by 10% or cracks appear, immediately replace the entire chain, and local repairs are strictly prohibited.

Brake pad replacement: When the thickness of the brake pad wears down to 2/3 of its original size, replace it with a new one to ensure reliable braking.

4、 Environmental adaptability improvement

Anti corrosion measures

Coating protection: Spray anti-corrosion coating (such as epoxy resin) on the surface of the equipment to enhance salt spray resistance.

Cathodic protection: In severely corroded areas such as ship decks, sacrificial anodes are installed on metal components of manual hoists to slow down electrochemical corrosion.

temperature control

High temperature protection: When working in tropical waters, avoid prolonged exposure of equipment to sunlight to prevent lubricant deterioration or plastic component aging.

Low temperature start-up: Before sailing in cold regions, preheat the gearbox to prevent the lubricating oil from solidifying and causing operational delays.

Vibration isolation

Shock absorption installation: Install the manual hoist on the shock absorption bracket in the cabin with severe vibration to reduce the impact of vibration on the components.

Fixed reinforcement: Use bolts to fix the equipment base on the deck to prevent equipment displacement or overturning caused by ship shaking.

5、 Personnel training and management

professional training

Operation certification: All operators must undergo training on the operation of marine manual hoists, mastering equipment performance, safety regulations, and emergency response measures.

Case study: Regularly organize accident case analysis meetings to strengthen safety awareness and avoid repetitive errors.

health management

Physical fitness test: Conduct regular physical fitness tests on operators to ensure that they have the physical strength to operate manual hoists for a long time.

Labor protection: Provide personal protective equipment such as anti slip shoes, gloves, goggles, etc. to reduce the risk of injury during operation.

Emergency Response Plan

Fault handling process: Develop an emergency plan for sudden failures of manual hoists, including steps for handling scenarios such as jamming and breakage.

Rescue drill: Regularly organize emergency drills to ensure that operators can quickly cut off power (if any), fix loads, and evacuate in emergency situations.

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