The GB/T 3141-1994 standard specifies the ISO viscosity classification method for industrial liquid lubricants, which is applicable to the production, selection and use of industrial lubricants. The standard divides lubricants into a series of viscosity grades based on kinematic viscosity at 40 ° C, and specifies the viscosity range and nominal value of each grade. This classification method provides a scientific basis for the uniform specification of lubricants, which is convenient for Manufacturers and users to choose the appropriate lubricant under different industrial equipment and working conditions, and ensures the Stability and efficiency of equipment operation. The implementation of the standard helps to improve the interchangeability of lubricants and promote the standardization and standardization of the industry.