Analysis of the causes of noise generated during the handling process of electric forklifts

1、 Wear and looseness of mechanical components

1. Door frame system issues

Excessive clearance between guide wheels and rollers: The clearance between the door frame guide wheels, rollers, and fork frames exceeds the standard, resulting in collision or friction sounds during movement.

Chain and sprocket wear: Excessive clearance between the chain and sprocket, or excessive clearance between the upper and lower pins of the fork and fork crossbeam, can cause vibration noise.

Loose fasteners: Parts such as car body guide wheels and rollers may experience wear and tear due to long-term use, resulting in increased gaps or loose fixing bolts, causing abnormal noise.

2. Bearing and gear issues

Bearing wear: Motor bearings, wheel hub bearings, etc. are worn due to insufficient lubrication or aging, resulting in mechanical friction noise.

Poor gear meshing: Excessive clearance or insufficient lubrication between the gearbox or drive gears can cause gear meshing noise.

2、 Hydraulic system issues

1. Hydraulic pump and valve noise

Hydraulic pump abnormality: Worn parts or poor oil suction inside the pump, resulting in fluid noise or mechanical vibration.

Poor sealing of control valve: Valve oil leakage or aging of seals, resulting in fluid impact sound.

2. Oil contamination

Hydraulic oil impurities: Metal particles or bubbles are mixed into the oil, causing the pump to have poor oil suction, resulting in vibration and noise.

Low oil level: Insufficient hydraulic oil causes the pump to empty, resulting in cavitation noise.

3、 Electrical system factors

1. Motor noise

Mechanical noise:

Bearing issue: Motor bearings are worn or poorly lubricated, resulting in periodic friction sounds.

Unbalanced rotor: Poor dynamic balance of the motor rotor leads to increased vibration during high-speed rotation.

Fan defect: The cooling fan blades are deformed or damaged, causing aerodynamic noise.

Electromagnetic noise:

Coil or magnetic circuit design issues: Electromagnetic vibration causes high-frequency whistling, especially noticeable when the load changes.

2. Controller and contactor

Poor contact: Electrical components (such as contactors and relays) have oxidized or aged contacts, resulting in arc noise.

Electromagnetic interference: Defects in the controller circuit design result in electromagnetic radiation, causing abnormal sounds.

4、 Friction between tires and the ground

1. Tire factors

Material matching with the ground: Solid tires make loud noise when rolling on rough ground, while inflatable tires increase friction when the air pressure is insufficient.

Foreign object jamming: foreign objects such as stones and metal fragments are stuck in the gaps of the tire, producing periodic impact sounds during movement.

2. Ground conditions

Uneven ground: When driving on bumpy or rough ground, the impact of tires on the ground produces noise.

Anti slip measures: Improper design of anti slip coating or texture on the ground increases friction noise.

5、 Improper operation and maintenance

1. Operational errors

Clutch semi linkage: Long term half stepping on the clutch causes friction plate wear and produces sharp noise.

Rapid acceleration/braking: Frequent sudden start and stop can cause mechanical component impact, resulting in abnormal noise.

2. Maintain deficiencies

Insufficient lubrication: Failure to regularly lubricate components such as chains and bearings leads to dry friction noise.

Gap not adjusted: The gaps between components such as door frames and chains were not adjusted in a timely manner, exacerbating wear and noise.

6、 Design defects

1. Structural resonance

Unreasonable component design: The natural frequencies of components such as door frames and frames coincide with the vibration frequency of the motor, causing resonance amplification noise.

Fan design defect: Improper shape and size of cooling fan blades, resulting in excessive aerodynamic noise.

2. Material selection

Low quality components: The use of low durability materials leads to rapid wear of components, such as plastic gears that are prone to aging and produce noise.

7、 Solution suggestions

Regular maintenance:

Check and adjust the clearance between the door frame and chain, lubricate the bearings, chains, and other components.

Replace worn guide wheels, rollers, or bearings, and tighten loose bolts.

Hydraulic system maintenance:

Regularly replace hydraulic oil, clean filter elements, and check the sealing of pumps and valves.

Electrical system optimization:

Check the motor bearings, replace the aging fan, and optimize the controller circuit design.

Tire and ground management:

Choose tires that are suitable for the ground, regularly clean the tires of foreign objects, and keep the ground flat.

Operation training:

Standardize operating procedures, avoid sudden acceleration/braking, and reduce clutch half engagement.

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