Polyurethane drum coating has the following advantages: hydrolysis stability, anti-aging, acid and alkali resistance and other chemicals have excellent functions; it is not easy to burn, and its flame retardancy is satisfactory to national security. The density is high, and the density can be adjusted at 200-500kg/cubic meter according to different application occasions, and the tightening strength can reach 4-20MPa. The thermal conductivity is 0.052, with low thermal conductivity, low moisture permeability, low water absorption, and satisfactory for cold preservation.