The application of polymer materials in the machinery industry is becoming more and more extensive. “To replace steel with plastic” and “plastic iron” have become the hot and important focus of current material science research. This type of research broadens the range of materials used to make mechanical products shift from traditional safety, bulkiness, and high consumption to safety, lightness, durability, and economy. For example, polyurethane elastomers have a high wear resistance, and in some organic solvents such as kerosene and mortar mixtures, the wear is lower than other materials. Polyurethane elastomer can be made into flotation machine impeller and cover plate, which is widely used in flotation machinery with abrasive conditions. Another example is polyoxymethylene, which has outstanding wear resistance. The wear resistance of metal is smaller than that of nylon. It is modified with PTFE, engine oil, disulfide, chemical lubrication, etc., and its friction coefficient and wear amount are smaller. Due to its good mechanical properties and wear resistance, POM is widely used in the manufacture of structural components such as gears, bearings, cams, nuts, various pump bodies and guide rails. A large number of non-ferrous metals such as zinc, copper and aluminum have been replaced in the automotive industry, which can replace cast iron and steel stampings.