Improper operation, insufficient maintenance, or harsh environment during the operation of electric winches can easily cause equipment damage. The following are three common situations that can easily cause damage to electric winches and their specific analysis:

1、 Overloaded operation or frequent start stop

overload operation

Phenomenon: The winch continues to operate beyond its rated load, resulting in motor overheating, brake system failure, or wire rope breakage.

Reason:

The motor design has a fixed power, but when overloaded, the current surges rapidly, the winding temperature rises rapidly, accelerating insulation aging, and even burning out the motor.

The braking system (such as disc brakes) has insufficient friction when overloaded, which prevents effective braking and leads to equipment loss of control.

The steel wire rope bears a tensile force exceeding its breaking force, causing a rope breakage accident.

Case: When using an electric winch to lift building materials at a construction site, overloading occurred due to incorrect load estimation. After running for 5 minutes, the motor emitted smoke, the brake failed, the steel wire rope broke, and the equipment was scrapped.

Preventive measures:

Strictly use according to the rated load and prohibit overloading.

Install overload protection devices (such as current relays) that automatically shut down when the current exceeds the rated value.

Regularly test the performance of the braking system to ensure that the braking torque meets the requirements.

Frequent start stop

Phenomenon: The motor starts and stops multiple times in a short period of time, causing damage to the winding insulation or erosion of the contactor contacts.

Reason:

When the motor starts, the current is 4-7 times the rated current. Frequent starting and stopping will cause the motor winding to withstand repeated impacts and accelerate insulation aging.

Contactor contacts are prone to arcing during frequent on-off processes, leading to contact melting or erosion, which affects the reliability of control circuits.

Case: Due to frequent adjustment of load position by operators, the electric winch at a certain port caused the motor to start and stop hundreds of times a day. Three months later, the motor winding short circuited and the contactor contacts were severely eroded.

Preventive measures:

Optimize the operation process and reduce unnecessary start stop times.

Choose heavy-duty contactors to improve contact capacity and arc resistance.

Install a soft starter to reduce the impact of starting current.

2、 Insufficient lubrication or contamination of lubricating oil

Insufficient lubrication

Phenomenon: Excessive wear of components such as gearboxes and bearings due to lack of lubrication can lead to increased equipment noise, intensified vibration, and even jamming.

Reason:

Insufficient or untimely replenishment of lubricating oil can cause direct contact between friction pairs (such as gears and bearings), resulting in high temperatures and wear.

Improper selection of lubricant viscosity (such as using low viscosity oil in high-temperature environments) cannot form an effective oil film.

Case: Due to long-term lack of lubricating oil, the gearbox gear of an electric winch in a certain mine suffered severe wear. After running for 2 years, the gear tooth surface peeled off, and the equipment was shut down for maintenance.

Preventive measures:

Regularly check the oil level and replenish lubricating oil according to the instructions (such as using winter gear oil or saturated cylinder oil for the gearbox).

Choose lubricating oil with appropriate viscosity based on the ambient temperature (such as using high viscosity oil in high-temperature environments).

Install an oil level alarm device that automatically shuts down when the oil level is low.

Lubricating oil pollution

Phenomenon: Metal particles, moisture, or impurities are mixed into the lubricating oil, leading to accelerated wear of the friction pair or lubrication failure.

Reason:

The equipment is poorly sealed, and external dust and moisture enter the lubrication system.

Failure to replace lubricating oil in a timely manner leads to aging and deterioration of the oil, resulting in sedimentation.

Case: An electric winch at a construction site suffered from damage to the gearbox seal, which led to rainwater entering the lubrication system and causing rusting and corrosion of the gears. After one year of operation, the gears broke.

Preventive measures:

Regularly replace the lubricating oil (such as replacing the gearbox once a year) and clean the oil tank and filter screen.

Strengthen equipment sealing maintenance and replace damaged seals in a timely manner.

Install oil detection sensors to monitor oil quality (such as moisture and particle size) in real-time.

3、 Brake system failure or improper maintenance

Brake system failure

Phenomenon: The winch cannot brake normally during operation, resulting in equipment loss of control or pulley accidents.

Reason:

The brake friction plate is severely worn and the braking torque is insufficient.

Brake cylinder or hydraulic system leakage, insufficient pressure.

Fatigue or fracture of the brake spring leads to a decrease in braking force.

Case: During the lifting of heavy objects, the brake of an electric winch in a power plant suddenly malfunctioned, causing the equipment to be damaged by the falling object. Fortunately, no casualties were caused.

Preventive measures:

Regularly check the thickness of the brake friction plate and replace it in a timely manner when the wear exceeds the limit.

Test the sealing of the brake cylinder or hydraulic system and repair any leaks.

Verify the elasticity of the brake spring to ensure it meets the design requirements.

Improper maintenance of the braking system

Phenomenon: The brake action is not responsive, the braking time is too long, or the braking distance exceeds the standard.

Reason:

Improper adjustment of the brake (such as excessive clearance between the brake shoe and the brake wheel) can result in insufficient braking force.

The brake system has poor lubrication and the action is stuck.

The brake signal device is malfunctioning and unable to trigger the brake in a timely manner.

Case: A logistics company's electric winch experienced a delay in braking time due to loose brake adjustment screws and excessive clearance between brake shoes and brake wheels, resulting in cargo slipping during transportation.

Preventive measures:

Regularly adjust the brake clearance (such as when releasing the brake, the clearance between the brake shoe and the brake wheel should be ≤ 0.7-0.8mm).

Lubricate and maintain the transmission components of the braking system, such as levers and connecting rods.

Test the brake signal device (such as deceleration alarm bell, over roll protection switch) to ensure that the action is sensitive and reliable.

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