Common Fault Analysis and Improvement Suggestions for Electric Winch

1、 Motor starting fault

Fault phenomenon: After pressing the start button, the motor does not respond.

Root cause analysis:

Power supply issues: power outage, phase failure, line grounding, or low voltage (below 85% of rated voltage).

Control circuit failure: Stop button not reset, internal components of starter damaged (such as contactor coil burned out), operation cable disconnected.

Motor body failure: winding burnout or insulation aging.

Improvement suggestions:

Power supply inspection: Use a multimeter to check the power supply voltage and confirm if there is a phase loss or grounding. If other devices cannot start, contact the power supply department to restore power supply.

Control circuit troubleshooting: Check if the stop button is stuck, use a megohmmeter to check the insulation of the operating cable, and replace damaged starter components.

Motor maintenance: Use a multimeter to measure the winding resistance. If a short circuit or open circuit is found, the motor needs to be replaced or the coil needs to be rewound.

2、 Motor single-phase operation fault

Fault phenomenon: The motor makes a "buzzing" sound when starting, and the rotor swings but cannot rotate; During operation, the speed decreases and the current abnormally increases.

Root cause analysis:

Power phase loss: blown fuse, broken circuit, or poor contact of contactor contacts.

Internal fault of the motor: One phase of the stator winding is broken (star wiring has a more serious impact).

Improvement suggestions:

Power side inspection: Use a multimeter to check the three-phase voltage, confirm whether the fuse is blown, repair the broken wire or replace the contactor.

Motor side treatment: If the stator winding is broken, the original winding parameters (form, number of turns, wire gauge) need to be recorded and rewound to avoid arbitrary changes that may cause performance degradation.

3、 Brake system malfunction

Fault symptoms: Brake brake overheating, weak braking or inability to release.

Root cause analysis:

Improper operation: using the brake too early, too much, or too forcefully.

Brake wear: Excessive wear of brake shoes, loose bolts, or insufficient contact area.

Hydraulic system failure: blockage of overflow valve, oil leakage of electro-hydraulic pressure regulating device, or disconnection of action coil.

Improvement suggestions:

Operating standards: Strictly control the traction load to avoid the motor not delivering power and releasing the switch when the load is lowered.

Brake maintenance: Regularly check the wear of brake shoes, adjust the tightness of bolts, and ensure that the contact area between brake wheels and brake shoes is ≥ 75%.

Hydraulic system repair: Clean the overflow valve orifice, replace the seal or electro-hydraulic pressure regulating device, and weld the broken part of the action coil.

4、 Wire rope arrangement malfunction

Fault phenomenon: The steel wire rope is tangled haphazardly on the drum, causing increased wear or slipping out of the drum.

Root cause analysis:

Installation issue: Improper arrangement of winch, excessive deviation angle of lifting wire rope.

Maintenance deficiency: lack of oil in the pulley, failure or improper operation of the rope arrangement device.

Improvement suggestions:

Installation adjustment: Re calibrate the winch position to ensure that the center of the drum is aligned with the track and the deviation angle meets the equipment requirements.

Maintenance enhancement: Regularly lubricate the pulley, check the function of the rope arrangement device, and maintain tight winding during operation.

Emergency response: If the height of the pile exceeds the edge of the drum, immediately stop the vehicle for repair to avoid accidents such as broken ropes and racing cars.

5、 Abnormal noise and vibration of reducer

Fault phenomenon: The reducer produces abnormal noise and the body vibrates during operation.

Root cause analysis:

Gear meshing problem: too tight or too loose clearance.

Bearing malfunction: excessive clearance or damage.

Loose bolts: The reducer or bearing bolts are not tightened.

Foreign object intrusion: Metal debris falls into the reducer.

Improvement suggestions:

Gear adjustment: Use a feeler gauge to measure the meshing clearance and adjust it to 0.2-0.4mm (according to the equipment manual).

Bearing replacement: If the radial clearance exceeds 0.1mm (checked with a dial gauge), replace the bearing and lubricate it.

Bolt tightening: Regularly check and tighten all connecting bolts.

Cleaning the interior: Disassemble the reducer after stopping the machine, remove foreign objects, and replace the lubricating oil.

6、 Control system malfunction

Fault phenomenon: Inability to start, inaccurate stop, or signal failure.

Root cause analysis:

Operation button malfunction: water ingress or contact oxidation inside the button.

Line fault: Short circuit of operating wire, grounding or burnt contact of magnetic starter.

Intermediate relay malfunction: Contact adhesion or continuous disconnection.

Improvement suggestions:

Button replacement: Disassemble the button, clean the contacts with alcohol, and replace the sealing ring.

Line detection: Use a megohmmeter to measure insulation resistance, repair short circuits or grounding points.

Relay repair: Replace burnt magnetic starter contacts or intermediate relays.

7、 Lubrication system malfunction

Fault symptoms: Overheating of bearings, increased noise, or jamming of transmission components.

Root cause analysis:

Insufficient lubrication: Failure to regularly replenish lubricating grease.

Lubrication deterioration: Oil mixed with water or impurities.

Improvement suggestions:

Regular lubrication: Add ZL-3 lithium grease every 5000 hours of operation, with the filling amount controlled at 1/2 (2-pole motor) or 2/3 (4/6/8-pole motor) of the bearing cavity.

Oil replacement: If the lubricating grease turns black or has water stains, immediately clean the bearing and replace it with new grease.

8、 Installation and environmental issues

Fault phenomenon: The winch operates unstably and components are damaged prematurely.

Root cause analysis:

Improper installation position: The winch is close to the coal wall or the slope exceeds the standard.

Adverse environment: moisture, corrosive gases or dust intrusion.

Improvement suggestions:

Reinstall: Ensure that the center of the winch drum is aligned with the track and the slope meets the equipment requirements (usually ≤ 15 °).

Environmental improvement: Install dehumidifiers in the winch room, regularly clean dust, and apply anti rust paint to exposed parts.

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