Joint bearing preload to control during the installation process is mainly the angle contact ball bearing, the eccentric bearing, tapered roller bearing, tapered bore double row cylindrical roller and so on, in this final stage of several types of NSK bearing installation, is to accurately mediation clearance, which control the preload (load), especially the shafting strictly requirements for machine tool spindle on rotary precision, noise, temperature rise, not only in the initial installation should control the preload (load) mediating clearance, and also to mediate in use. Preload control methods more, here are some control preload mediation clearance.
The so-called joint bearing burn injury refers to: rolling wheel, a rolling body of the bearing and cage spinning rapidly heating until the discoloration, softening, melting and breakage.
The main causes of bearing burn is due to poor NSK bearing lubrication, may use the informal lubricant or lubricant, too much, too, is not correct. The second may be excessive load (preload is too large). Speed is too high. Clearance is too small. Water or other foreign bodies penetrated. If the deflection above two conditions are not so is shaft, bearing housing poor accuracy, the large shaft. See here, I think we all want to know the solution, first of all, to study the lubricant and lubrication method, selection of joint bearing lubricant, and its amount, but also to rectify the bearing selection. Research should cooperate, bearing clearance and preload, and improved sealing device. Check the shaft and bearing box accuracy.
Deformation of the preloaded spring, a spring load and deformation of the relationship, in order to control the deformation to adjust load preload.
The axial displacement of NSK bearings, bearings with a tapered bore in advance with the eccentric bearing axial load and axial displacement of the relationship, in order to control the axial displacement of the mediation preload.
Joint bearing end cover pad, will cause the end of the other end bearing tightening, not into the gasket, tighten the screws, when you can not free move that has no clearance, shaft, end cover and the end surface clearance bearing seat with feeler gauge equivalent, the space required to add this numerical value is the thickness of the gasket.
Detection of the eccentric bearing preload is relatively difficult, few detection with special instruments, mostly with dial indicator measuring shaft axial, radial displacement or starting friction torque to detect, some overseas bearing the company to preload is always the best value, recovery of special instruments and some layout host detection and mediation of pretension load, implementation of the preload can control.
Nut fastening torque, the nuts of a NSK bearing, fastening nut torque control to adjust preload.
Eccentric bearing the starting friction torque, a joint bearing the starting friction torque and axial load of the relationship, in order to control the starting friction moment to adjust the preload, commonly used in the axial pre installed in pairs of tapered roller bearings.