JJF (Mechanical) 048-2009 Abrasives Rockwell hardness tester calibrate specification is a calibrate standard for abrasives Rockwell hardness testers to ensure the measurement accuracy and reliability of hardness gauges. The specification details the scope, method, environmental conditions and required equipment of calibrate, which is suitable for new manufacturing, in use and after repair Rockwell hardness testers. The standard highlights key technical requirements in the calibrating process, including calibrate frequency, calibrate records and uncertainty assessment of results. Through the standardized calibrating process, the standard provides a scientific basis for the abrasive industry, promotes the standardized management and quality control of hardness gauges, and ensures the mass and safety of products. The standard was published in 2009 and has become an important reference in this field.