Effect of temperature on preload of space precision bearing 2018-09-28 16:24:38

Effect of temperature on preload of space precision bearing

Angular contact ball bearings are one of the core mechanical components commonly used in space precision shafting. Axial preloading of bearings is a key
Technology. The space precision shafting system adopts back-to-back or face-to-face positioning pre-tightening, and changes the length difference of the inner and outer spacers.
Change the preload. Reasonable pre-tightening force can reduce vibration and noise while prolonging the service life while ensuring the stiffness and rotation accuracy of the shafting.
Life. If the pre-tightening force is too large, the friction torque, power consumption and temperature rise of the bearing will increase, and the fatigue life will be reduced. If the pre-tightening force is too small, the rigidity will be low.
Easy to slip, which increases wear and reduces life. With the gradual improvement of the accuracy and performance requirements of space products in recent years, especially the application of ceramic ball hybrid bearings, the change of ambient temperature and the temperature gradient inside the bearing on the performance of the product
The influence is more and more prominent, and the root cause lies in the change of the pre-tightening force caused by thermal expansion. Introduced the use of bearings to start friction torque, shaft
Friction and spacer friction 3 kinds of bearing pre-tightening force test principle and method; analysis of temperature change to interference or clearance
Influence, derivation of the relationship between bearing clearance and preload, and verification; analysis of centrifugal force, working temperature and surface
The effect of roughness on the effective interference, and the calculation and verification of the preload
From the perspective of bearing axial clearance and stiffness, the working temperature and ladder are analyzed for all-steel bearing and ceramic ball hybrid bearings respectively.
The degree of influence on its preload, as well as the impact of back-to-back and face-to-face two different installation methods, clear quantitative estimation methods.
The pre-tightening force on-line test method based on the strain-measuring principle is used to measure the pre-tightening force of two kinds of bearings at different temperatures.

Effect of temperature on bearing contact angle and axial clearance
The shafting system is often assembled at room temperature. Due to the temperature difference between the working environment temperature and the normal temperature, and the temperature rise due to the operation,
The parts that make up the bearing will inevitably undergo thermal deformatio