The wheel connection pair is an extremely important component in vehicle applications, and its function is to reliably connect the wheel and the hub to ensure the safe driving of the vehicle. The failure of the wheel connection pair will lead to serious consequences, which will not only cause damage to vehicle parts, but also cause heavy economic losses and casualties.
The failure of the wheel connection pair is mainly due to the loose connection pair and the breakage of the bolt, and the direct result is that the wheel will fly out and cause an accident. Through the analysis of multiple wheel bolt fracture failures, the loosening of the bolt pair before the fracture causes the pre-tightening force to drop, causing the relative movement between the wheel and the hub, and causing the bolt to be subjected to the shear force of the wheel mounting hole to cause fatigue fracture is the main reason. Therefore, stable preload is an important factor to ensure the normal connection of the wheels.
Share the influence of different surface treatment methods on the friction coefficient of wheel nuts to improve the reliability of wheel tightening.
1) Through the analysis and calculation of wheel bolt torque and preload force, it is concluded that the size of the preload force in constant torque assembly depends on the friction coefficient of the thread surface and the friction coefficient of the contact surface, and the slight change of the friction coefficient has an effect on the preload force. great impact.
2) Through the measurement of friction coefficient, the friction coefficient of the contact surface of the wheel connecting pair is much larger than that of the thread, and the friction coefficient of the contact surface has a great influence on the comprehensive friction coefficient.
3) It can be seen from the test data that white zinc plating and yellow zinc plating have little effect on the friction coefficient of the contact surface, thread friction coefficient and comprehensive friction coefficient. In the absence of external friction coefficient sealant, the thread friction coefficient is relatively stable. It shows that the thread processing and surface treatment process of this batch of nuts are consistent, but the friction coefficient of the contact surface fluctuates greatly. Because of the anti-rust oil, the friction coefficient of the contact surface is very stable.
4) Through the test and detection of wheel nuts with different surface treatment forms in normal supply state, it is concluded that the nut with phosphating treatment method can provide a very stable comprehensive friction coefficient without using friction coefficient sealant, that is, it can Provide a stable and controllable preload to ensure reliable connection of the connecting pair.
zj-junyue.com