Composite polyurethane materials, mould and pouring and coating technologies are analyzed for the defects existing in the preproduction of composite polyurethane-based insulation coating for pipeline, such as bubble, unwanted pattern, coating thickness deviation, unacceptable caking property, improper processing method of glass hollow microsphere, etc. Solutions are given to make an acceptable pipe. Moreover, a better process flow of composite polyurethane-based insulation pipe is obtained, and the process parameters are optimized.
