Shanxi Provincial Bureau of Quality Supervision sampled 50 batches of bearings with a pass rate of only 46%

Not long ago, Shanxi Provincial Bureau of Quality Supervision carried out supervision and spot checks on the quality of 50 batches of bearings in Taiyuan and Jinzhong districts, and qualified 23 batches. The sampling pass rate was 46%. Unqualified 27 batches were produced by other provinces and cities.

In this spot check, the hardness of some of the bearings did not meet the standard requirements. In the course of use, it was easy to cause wear, cracks and other failures, affecting the normal operation of machinery and equipment. Bearings in the continuous operation process, should meet the running accuracy and friction torque and other requirements, but this spot check some companies in the chamfer limit deviation does not meet the requirements, making the bearing assembly is not accurate, affect the bearing's running accuracy, easy to generate spallation To reduce the service life.

The main reasons for these problems are as follows: First, the production process is not strictly controlled in the production process, and the heat treatment of materials is not closed. Second, a few enterprises have insufficient understanding of the standards and cannot strictly organize production according to the standards. In this random inspection, the 6309 type ZGLY-SP brand bearings produced by the nominal Luoyang Shuangping Bearing Co., Ltd. distributed by the Jinshi Materials Sales Office of Taiyuan City all failed to meet the standards for hardness, dimensional accuracy, width deviation and variation.