Excessive noise when using lift hoists how to do?

Windlass great many causes excessive noise, but the essence is the result of shock and vibration, generally due to the poor quality of the gear meshing, movement is not smooth in motion produces instantaneous acceleration caused. , Here you explain too much noise when using  Hoist equipment  how to do?
Design and manufacture of chassis caused by the presence of noise may: ① chassis with box-shaped structure, not all welds are continuous welding, various chassis weld length, height different positions, there is a big individual differences in chassis rigidity, while others resonate effect, if any one o'clock machine vibration noise is amplified; ② by a steel plate welded into the chassis, do not have the shock absorption silencer function if its natural frequency and the gear mesh frequency is close to the individual machines may cause weak due to vibration caused by the larger gear total shock, cause noise value rises.
Bearing clearance who believe that since the noise is accompanied by drum assembly and transmission parts, then it may be due to the roll bearing large gap caused.

Workaround:
1, we focused on the possibilities were tested, but through three experiments found that the noise level and chassis structure, stiffness, frequency and other factors were weakly correlated noise is strongly related to the size of moving parts, so constructed chassis design, manufacturing quality is not excessive noise causes.
2, we choose the roll parts with the gap, the gap to ensure compliance with the spindle bearing bore drawings,chain block test after assembly. Test using frequency motor speed, observe speed on the noise.
Large number of experimental results show that the speed of the noise impact is the first one, the higher the speed the noise roll larger the value the more intense vibration machine; gap in the second, the spindle and sleeve gap the greater the greater the noise; while the chassis minimal impact on noise. If the machine is already very low noise, the speed level, the spindle gap size changes will not produce excessive noise, which shows that excessive noise nor by the bearing clearance.