The noise generated by the reducer of the lever chain crane is mainly due to problems in the design, manufacturing, installation, and maintenance of components such as gears, bearings, and casings. The specific reasons and analysis are as follows:

1、 Gear related issues

Insufficient gear machining accuracy

Tooth profile error: Deviation in gear tooth profile shape can cause impact and vibration during meshing, resulting in high-frequency impact sound.

Base deviation: affects the starting position of gear meshing, resulting in poor contact and noise generation.

Tooth orientation error: causes uneven contact between gears in the tooth length direction, resulting in excessive local force and causing vibration and noise.

Radial runout of gear ring: When the gear rotates, it swings radially, causing periodic changes in meshing clearance and generating low-frequency noise.

Unreasonable gear design parameters

Insufficient tooth width: As the unit load increases, the bending deformation of the gear teeth intensifies, and the noise increases.

Excessive tooth pitch: The number of teeth meshing simultaneously decreases, the force on a single gear increases, and the noise increases.

Improper selection of pressure angle: If the pressure angle is too small, it will reduce the contact strength of the gear, while if it is too large, it will increase friction and noise.

Unreasonable displacement coefficient: Failure to optimize the displacement coefficient may result in excessive gear root cutting or backlash, causing noise.

Poor surface quality of gears

Excessive roughness of tooth surface: Rough tooth surface will intensify friction and wear, producing high-frequency noise.

Insufficient tooth surface hardness: Hard tooth surface gears need to be carburized and hardened to improve their load-bearing capacity, but if the heat treatment deformation is not corrected, it will lead to increased noise.

2、 Bearing related issues

Insufficient bearing accuracy

When there are spots, grooves, peeling or rust on the inner or outer ring or rolling elements of the bearing, a sharp whistle or impact sound will be emitted.

Improper installation of bearings

Improper tapping or collision during installation can cause bearing damage or excessive clearance, resulting in noise.

Insufficient or excessive pre tightening force of the bearing affects the smooth operation of the shaft, causing vibration and noise.

Poor lubrication of bearings

Insufficient lubricating oil, deteriorated oil quality, or incorrect model can cause the bearing to fail to form an effective oil film, resulting in a "squeaking" sound when metal directly rubs against it.

3、 Box and assembly issues

Insufficient precision in box processing

Insufficient precision of box holes (such as aperture, center distance error, parallelism and inclination of each hole centerline) can affect the assembly accuracy of bearings and gears, resulting in noise.

Unreasonable box structure (such as non cylindrical box) or insufficient rigidity can easily cause resonance and amplify noise.

Insufficient assembly accuracy

Abnormal gear transmission at all levels, excessive or insufficient meshing backlash, poor tooth surface meshing, resulting in vibration and noise.

Misalignment of component installation and excessive deviation of shaft alignment result in additional vibration and noise.

Loose components (such as bearing pre tensioning mechanism, shaft positioning mechanism, etc.) can cause inaccurate system positioning, abnormal position engagement, and generate noise.

4、 Usage and maintenance issues

Lubrication failure

Lubricating oil containing impurities, insufficient oil quantity, or aging can exacerbate friction and wear, producing metallic friction sounds.

Load overload

If the load exceeds the rated capacity of the gearbox, it will cause excessive force on the gears and bearings, resulting in abnormal noise.

Improper operation

Frequent start stop, sudden reverse operation, or unreasonable speed setting can cause impact torque and increase noise.

Insufficient maintenance

Long term failure to replace lubricating oil, clean internal debris, or replace worn parts in a timely manner can lead to a gradual increase in noise.

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