Common Faults and Solutions of Pallet Truck

Pallet truck are important equipment in the logistics and warehousing fields. Their stable operation is crucial for work efficiency. However, during use, the equipment may encounter faults due to hydraulic systems, mechanical components, or improper operation.

I. Hydraulic System Faults

1. Forks cannot be raised or lowered

(1) Unable to press down/insufficient rise

Reasons:

Insufficient hydraulic oil or impure oil quality.

Incorrect position of adjusting bolts (such as the valve body always being in an open state).

Air in the hydraulic cylinder.

Solution:

Replenish hydraulic oil to the specified level and replace with clean hydraulic oil.

Adjust the position of the adjusting bolts to ensure the valve body closes properly.

Remove air from the cylinder (by repeatedly operating the handle to exhaust).

(2) Unable to lower

Reasons:

The pressure relief valve is not adjusted properly.

The piston rod of the cylinder is misaligned or deformed due to overloading.

Component damage (such as valve body, spring breakage).

Solution:

Adjust the pressure relief valve to the appropriate pressure.

Replace the deformed piston rod or cylinder, repair or replace damaged parts.

2. Abnormal lifting speed

(1) Slow rise speed

Reasons:

Hydraulic oil contains impurities or moisture.

The pressure relief valve is not adjusted properly, resulting in insufficient pressure.

Air in the oil pump.

Solution:

Replace with clean hydraulic oil and regularly clean the oil filter.

Adjust the pressure relief valve pressure and remove air from the oil pump.

(2) Slow ascent or crawling

Reasons:

Severe leakage in the hydraulic system, aging or damaged sealing rings.

Air mixed in the cylinder.

Solution:

Tighten the oil drain screw and replace the aged sealing rings.

Remove the air from the system (by repeatedly operating the handle to ascend and descend).

3. Forks automatically descend

Reasons:

Hydraulic oil contains air or impurities.

The pressure relief valve is not adjusted properly, or the sealing parts are damaged.

Solution:

Remove the air from the cylinder, replace with clean hydraulic oil.

Adjust the pressure relief valve pressure and replace the damaged sealing parts.

II. Mechanical Component Faults

1. Leakage problem

Reasons:

Sealing parts (such as oil seals, O-rings) are worn or damaged.

Components crack or connections are loose.

Solution:

Replace with new sealing parts, check and tighten connections.

Weld or replace cracked components.

2. Insufficient lifting capacity

Reasons:

Hydraulic oil contains impurities causing the one-way valve to fail.

Overloading damages hydraulic components.

Solution:

Replace with pure hydraulic oil, clean the impurities in the one-way valve.

Avoid overloading and follow the rated load of the equipment.

3. Crawling when unloaded

Reasons:

Frame deformation leads to increased friction.

Air in the cylinder.

Solution:

Correct the frame deformation, adjust the adjustable screws of the roller shaft.

Adjust the nut on the upper part of the cylinder, loosen the overly tight sealing ring.

III. Other Common Problems

1. Hydraulic pump failure

Reasons:

Hydraulic oil impurities cause internal wear of the pump.

Pump shaft is bent or blades are broken.

Solution:

Clean or replace the hydraulic oil, repair internal parts of the pump.

Replace the bent pump shaft or broken blades.

2. Valve problems

Reasons:

Safety valve set pressure is too low or the valve core is stuck.

Electromagnetic valve coil is burned out (for electric handling vehicles).

Solution:

Adjust the safety valve pressure, clean or replace the valve core.

Replace the electromagnetic valve coil, check the wiring of the electronic control components.

3. Overloading or improper operation

Reasons:

Overloading of goods causes the hydraulic system to overload.

Worn or damaged wheels affect movement.

Solution:

Strictly follow the rated load, place goods evenly.

Check and repair the wheels, remove foreign objects that are stuck.

Before maintenance, turn off the power supply to ensure complete pressure relief of the equipment.

Preventive maintenance:

Establish equipment files to record maintenance times and replaced components.

Provide professional training for operators to standardize operation procedures.

By implementing these measures, the failure rate of hydraulic handling vehicles can be effectively reduced, the service life of the equipment can be extended, and the efficiency of warehousing and logistics can be guaranteed.