The technical cleanliness of components is crucial to their performance in finished products. As such, the assessment of the level of cleanliness of components is applicable in a wide range of industries, e.g. any involving the manufacture of mechanical devices such as the automotive industry. A typical example of such a component is ball bearings which are at the heart of almost every product with a rotating shaft.
The manufacture of bearings is a very precise process with, in some cases, very low tolerances being required. It is entirely possible for a particle of 5 microns or less to cause a precision bearing to fail; very small particles have the potential to cause major damage. Even if such particles are not the immediate cause of failure, they can decrease a bearing’s smooth running qualities and low torque values and impact on its lifetime. Therefore it is important that a high degree of cleanliness is maintained during the manufacture of precision bearings. As a result, an assessment of cleanliness as part of quality control is crucial to ensuring consistent bearing performance. Residual particles may originate from the manufacturing or assembly processes or be introduced from the environment. In order to know if particle levels are within acceptable limits and in order to attempt to identify the source of particles, it is important to know both their composition and morphology so that the manufacturing processes can be monitored and optimised.