The bearing housing introduced here is a key part in the antenna base of a certain product. This bearing housing is a precision thin annular part with extremely high accuracy requirements, making it difficult to machine and prone to defects, while also having a long production cycle. This critical part, the bearing housing, has become a bottleneck in precision production processing.
2. Challenges in machining the bearing housing
The drawing of the bearing housing part is shown in Figure 1. The material for this part is GCr15 bearing steel, hardened to HRC ≥ 61. Furthermore, as can be seen from the figure, the form and position tolerance requirements are very high, with concentricity and total runout both at 0.015, and cylindricity at 0.002. After precision grinding, the part must ensure these form and position tolerances, which imposes strict requirements on the parallelism of the two end faces used for positioning during clamping in precision grinding. Therefore, in the process design, the process requirement is to improve the parallelism of the A and B end faces to 0.001. In previous machining, high-precision surface grinding was used for this part, but the achieved parallelism could only reach 0.005～0.008. Subsequent processes required a significant amount of flat lapping work to improve the parallelism of the part to 0.001, which took a long production cycle to meet the process requirements.