When operating manual hoists (including manual hydraulic balance weight single arm cranes, etc.), common faults can be divided into four categories: hydraulic system faults, mechanical component faults, electrical system faults, and operational faults. The following are specific analysis and improvement suggestions:

1、 Hydraulic system malfunction

Insufficient pressure

Reason: Wear of hydraulic pump, malfunction of relief valve, stuck reversing valve, leakage in hydraulic cylinder, blockage of damping hole or stuck valve core of balance valve, presence of air in the system.

Improvement suggestions:

Disassemble the hydraulic pump, inspect the gears, blades, and other parts, and replace those with severe wear.

Clean the overflow valve, remove internal impurities, and readjust the set pressure.

Clean and properly grind and repair the valve core, or replace the electromagnet.

Check the piston seal and replace it promptly if it is damaged.

Clean and inspect the balance valve to ensure smooth damping holes and flexible valve core movement.

Open the exhaust valve and make each mechanism reciprocate multiple times to exhaust the air.

Wear or looseness of hydraulic pump

Reason: Long term use of the hydraulic pump may cause wear or loose installation.

Improvement suggestions:

Check the installation of the hydraulic pump and tighten any loose parts.

If the hydraulic pump is worn, replace the worn parts or replace the hydraulic pump as a whole.

Wear of hydraulic rod piston oil seal

Reason: Excessive wear of the oil seal leads to poor sealing and internal leakage.

Improvement suggestion: Disassemble the hydraulic cylinder and replace the piston oil seal.

2、 Mechanical component failure

The balance valve is not tightly sealed

Reason: Internal leakage of the balance valve caused the boom to sink.

Improvement suggestion: Disassemble and inspect the balance valve, and replace it if necessary.

Wear and damage of mechanical components

Reason: Long term use may cause wear or damage to mechanical components.

Improvement suggestions:

Check whether the tires and brakes are working properly, and replace damaged parts in a timely manner.

For weak rotation or motor failure, repair or replace the motor.

Check the gearbox for faults that may affect power transmission, and carefully inspect and adjust it accordingly.

3、 Electrical system malfunction

Circuit fuse open circuit or short circuit

Reason: Circuit malfunction caused damage to the fuse.

Improvement suggestion: Check the circuit fuse and replace damaged fuses.

Abnormal pilot pressure

Reason: Unstable or improperly regulated pilot system pressure.

Improvement suggestion: Check the pilot pressure and adjust it to the normal range.

Servo control valve - servo piston stuck

Reason: Internal jamming of servo control valve or servo piston.

Improvement suggestion: Clean and inspect the servo control valve and servo piston to ensure flexible operation.

4、 Operational faults

Improper operation leading to equipment damage

Reason: The operator did not follow the standard operation, such as overloading, diagonal pulling, frequent starting, etc.

Improvement suggestions:

Strengthen operator training to ensure familiarity with equipment performance and operating standards.

Strictly follow the operating procedures and prohibit dangerous operations such as overloading, diagonal pulling, and frequent starting.

When the load stays in the air for a long time without braking

Reason: Negligence or failure of operators to operate according to specifications.

Improvement suggestions:

When heavy objects need to stay in the air for a long time, the drum should be braked and the driver is not allowed to leave the control room.

Strengthen safety awareness training for operators to ensure compliance with safety regulations.

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