Preloading of lead screw, wire rail and bearing

1. The understanding of preloading of lead screw, wire rail and bearing is high-speed low load light preloading and low-speed heavy load high preloading. The preloading of the screw rod shall be 0.1 times of the dynamic load (according to THK), and the preloading of the rail shall be 0.13 times of the dynamic load (according to SCHNEEBERGER). The light, medium and heavy preloading of the bearing have detailed data on different samples (but the value is small). Moreover, for the lead screw, wire rail and bearing, generally speaking, when the load (axial load for the lead screw) exceeds three times of the preload, the preload fails.

2. Preload of lead screw, wire rail and bearing is mainly to improve structural rigidity and system accuracy retention.

3. Without preload, the best working condition cannot be reached.

4. Generally, functional components will give some parameters, but most of these parameters are recommended reference coefficients. The actual application depends on your specific structure, required accuracy and use status.

5. The calculation of structural stiffness is a very complicated process, and the preload is mostly felt by experienced assembly workers, just as it is said upstairs that it is difficult to measure itself.

6. For example, for the main shaft bearing (cylindrical roller), the general assembly method is to pre tighten it until the shaft stands up, and the outer ring will not fall off. Even if it can rotate freely, no one can say how large it is.