Melt Flow Index Tester is a special equipment for determining the melt flow rate of thermoplastics under certain conditions, and can indirectly determine the molecular weight of polymers. The melt flow rate (melt index) of thermoplastic refers to the molten mass or molten volume of the melt passing through the standard mouth mold every 10 minutes under a certain temperature and load of the plastic, expressed by MFR (MI) or MVR value, which distinguishes the viscous flow characteristics of thermoplastic in the molten state. It is applicable to engineering plastics such as polycarbonate, polyarylsulfone, fluoroplastics, nylon and other engineering plastics with high melting temperature, and also applicable to plastics with low melting temperature such as polyethylene (PE), polystyrene (PS), polypropylene (PP), ABS resins, polyoxymethylene (POM), polycarbonate (PC) resins and other plastics test, which is of great significance for the quality assurance of raw materials, products and other products made from thermoplastic plastics and chemical fibers.