When the bicycle bearing ball is operated, it mainly refers to the total distance that a certain ferrule can move in a certain direction with respect to the other ferrule. According to the direction of movement, it can be divided into radial clearance and axial clearance. The internal clearance of the bearing before installation must be distinguished from the internal clearance (running clearance) of the bearing when the operating temperature is reached after installation. The original internal clearance (before installation) is usually larger than the running clearance. This is due to the difference in the degree of fit involved in the mounting fit. The difference in thermal expansion between the inner and outer rings of the bearing and the related components causes the inner and outer rings to expand or reduce the internal clearance of the bearing and the specified value. of.
The size of the internal clearance of the bicycle bearing ball during operation has a great influence on the bearing performance such as fatigue life, vibration, noise, and temperature rise during operation. Therefore, the choice of bearing internal clearance is an important research project for bearings that determine the size of the structure. Generally, to obtain a stable test value, the test load specified by the bearing is given, and then the play is tested. Therefore, the measured clearance value is larger than the theoretical clearance (in the radial clearance, also called the geometric clearance), that is, one more elastic deformation due to the test load (called the test clearance). Show the difference).
The clearance before the installation of the bicycle bearing ball is defined by the theoretical internal clearance.
(1) The cooperation of the bearing with the shaft and the outer casing causes a change in the play.
(2) The change of the play is caused by the temperature difference between the inner and outer rings when the bearing is working.
(3) The material used for the shaft and the casing affects the change of the bearing clearance due to the difference in expansion coefficient.www.wxjnsteelball.com