Impact of pin hardness and hole tolerance

The shaft hole tolerance of the coupling generally follows the mechanical department standards H7 and H9, which can also be referred to as interference fit and transition fit for short.Among them, the interference fit means the positive tolerance, plus the tolerance of 10-20 wire, the holeSmall size minus shaftLThe difference in size isLInterference Ymax is the fit of hole and shaftTight state.Interference fit means that it can only be small but not large within the specified tolerance range. Excessive fit means that there is no oil. The specified tolerance can be large or small. Generally, if the shaft hole needs interference fit, it can be marked in the processing drawing. Or you can follow the principle of thermal expansion and contraction, and the shaft hole that needs to be hot-fitted can be interference fit, one is to facilitate the operation and installation of the worker, and the other is the coupling of the coupling tension sleeve.

For processing couplings, the data is still based on the standards of the Ministry of Machinery. If the coupling is designed without authorization, the torque is too large or the torque is too small, it will affect the use of the coupling.Because if the torque does not meet the rated use requirements, the torque or speed of the coupling will not meet the use requirements, which will cause the coupling to twist and break during operation.If the torque of the coupling designed by the designer is too large, it may not have much impact on the coupling itself, but it will cause the motor end shaft or the reducer end shaft to be used normally because of the excessive torque, so that it will not be protected. The role of the shaft.

The elastic pin is used on the TL-type elastic sleeve pin coupling, which is mainly used to drive the two half couplings to fix and transmit.And whether the hardness of the pin will change the torque of the coupling, the researchers have shown through experiments that for the standard data, the fixed number, size and material of the backrest pin will not change the torque too much, and if the number is increased If the size of the pin of the coupling becomes larger, or the material of the pin becomes harder, the torque of the coupling will change greatly.