Precautions For Connecting Flat Keys

According to usage requirements, the fit of flat key connections can be divided into three types:
1. Loose: The fit code for the hub and key is D10/h8, and the fit code for the shaft and key is H9/h8; Used in situations where the hub can slide axially on the shaft.
2. General: The matching code for the wheel hub and key is JS9/h8, and the matching code for the shaft and key is N9/h8; Used in situations where the load is not large, there is no need to eliminate the backlash, and the hub does not need to slide axially on the shaft.
3. Impact: The matching codes for the hub and key, as well as the shaft and key, are P9/h8; Used in situations where the load is large or there is an impact load, the return clearance needs to be eliminated, and the hub does not need to slide along the axial direction on the shaft.