The accuracy of angular contact ball bearing seems not too high. Is there any way to improve it? The accuracy of rolling bearings can be improved. The following are four common methods to improve the accuracy of rolling bearings.

1. The quantity of rolling load generated during excitation. When a load-bearing radial load is applied, the rolling quantity will change slightly during operation, including: 2-3-2-3 This causes an offset in the direction of the load. The resulting vibration is inevitable, but can be preloaded to reduce axial loading of all rolling elements.

2. Local damage

During operation, rolling across the damaged bearing components will produce a specific vibration frequency. Frequency analysis can identify damaged bearing components. This principle has been used in condition monitoring equipment to detect bearing damage. The temperature will rise sharply, resulting in abnormal high temperature. The reasons are too much lubricant, too small bearing clearance, poor installation, excessive friction of sealing device, etc. In the case of high-speed rotation, the wrong selection of bearing structure and lubrication mode is also the reason.

3. Accuracy of relevant parts

In case of close contact with the shape of the bearing collar, it is compatible with the shape of the bearing collar. If there is distortion during operation, vibration may occur. Therefore, the tolerance required for the machining of bearings and shafts is very important.

4. Pollutants

If you operate in a polluted environment, impurities may enter the rolling of the bearing. Vibration depends on the number, scale and composition of rolling impurity particles. Although the frequency does not produce a typical form, the reasons are poor lubrication, poor accuracy of shaft or bearing seat, bearing damage, foreign matter intrusion, etc., you can hear an annoying noise.

Measure the size of the shaft and bearing seat hole to determine the matching accuracy of the bearing. The matching requirements are as follows: the inner ring and the shaft adopt interference fit, and the interference amount is 0 ~ + 4 μ M (0 under light load and high precision); Clearance fit is adopted between the outer ring and the bearing seat hole, and the clearance is 0 ~ + 6 μ M (but when the angular contact ball bearing is used for the bearing at the free end, the clearance can also be increased); The roundness error between shaft and seat hole surface is 2 μ M below, the end face parallelism of the spacer used for the bearing is 2 μ M below, the runout of the inner end face and outer end face of the shaft shoulder is 2 μ Below m; The runout of the shoulder of the bearing seat hole to the axis is within 4 μ Below m; The runout of the inner end of the front cover of the main shaft facing the axis is within 4 μ Below M.

Installation of fixed end front bearing on the shaft: thoroughly clean the bearing with clean cleaning kerosene. For grease lubrication, first inject the organic solvent containing 3% ~ 5% grease into the bearing for degreasing and cleaning, and then fill the quantitative grease into the bearing with an oil gun (accounting for 10% ~ 15% of the bearing space volume); Heat the bearing to raise the temperature by 20 ~ 30 ℃, and install the angular contact ball bearing into the shaft end with an oil press; Press the set sleeve on the shaft and press the bearing end face with appropriate pressure to make it axially positioned; Roll the belt of the spring scale on the outer ring of the bearing and check whether the specified preload changes greatly by measuring the starting torque (even if the bearing is correct, the preload may also change due to the deformation of the fit or cage).