What are the general failure manifestations of the drum tooth coupling? What is the reason?

Drum tooth coupling is a more common kind of coupling, but the precision instrument accessories will fail with continuous use. What are the general failure manifestations of the drum tooth coupling? What is the reason?

wear

Wear is a common defect of the coupling. The connected shaft has relative slide to the coupling during operation, which is a prerequisite for wear. There are many other reasons leading to wear of the coupling, and the main reasons can be divided into 4 kinds.

Manufacturing process

The profile error between the teeth of the internal and external teeth of the coupling with good processing technology is small, the rotating torque transmitted on the coupling can be averaged to each tooth, and the coupling teeth with poor processing technology will be stressed unevenly, resulting in excessive force on individual teeth, resulting in serious wear will occur when the tooth loss.

Improper material application or poor surface heat treatment process,

If the material hardness of the internal and external teeth of the coupling is low, the wear resistance between the contact surface of the internal and external teeth is poor, it will also cause the wear of the coupling, the tooth surface of the drum tooth coupling is generally quenched or nitrided to improve its surface hardness and increase its wear resistance, but due to the improper heat treatment process, it will lead to insufficient tooth surface hardness.

Poor lubrication

Because the two rotating parts connected to the drum gear coupling move axially when rotating, it is ensured that the coupling has good lubrication. Poor lubrication effect or loss of lubrication will increase the friction between the coupling and the connected shaft, and lead to wear of the coupling for a long time.

Installation error

When the unit is installed, the center of the end face of the drive shaft and the driven shaft will be deviated. When the deviation exceeds the range allowed by the drum tooth coupling, the main oil pump will make a conical movement with the turbine rotor, resulting in the wear of the main oil pump bearing shell, the thrust tile and even the load swing of the hydraulic regulation system.

Lose a tooth

It is mostly due to the uneven force of the teeth of the coupling, such as the deviation of the tooth shape during processing, or the entry of hard objects into the local teeth during operation, resulting in the force of individual teeth, and the deviation during installation will make the local teeth stressed. Another reason for tooth loss is that the heat treatment process of the coupling is improper, and there are residual stresses and even cracks in individual teeth, which will cause this phenomenon.

During the maintenance, the inspection of the main oil pump coupling should be strengthened, especially when the abnormal wear of the main oil pump thrust tile is found, attention should be paid to it. When the coupling surface is found to be worn, the coupling should be replaced in time and the cause should be found, so as to avoid unsafe events caused by sticking during operation.