"DIN 53017-1993 viscosity measurement, Velocity Index Determination of Viscosity" is a standard issued by the German Institute for Standardization (DIN), which specifies the measurement method of the velocity index (temperature coefficient) of liquid viscosity with temperature. The standard is applicable to a variety of liquid materials, and the rate at which the viscosity changes with temperature is calculated by measuring the viscosity of liquids at different temperatures. The velocity index is an important parameter for evaluating the flowability and stability of liquids under different temperature conditions. It is widely used in quality control and Product Research & Development in the fields of lubricating oils, coatings, chemical raw materials, etc. The standard provides a scientific basis for the performance evaluation of liquid materials in industrial production.