The manufacturing process of 3PE Coated Steel Pipe, first inspect the Anti-corrosion Steel Pipe under various conditions so as to conform to the conditions of making the heat preservation steel pipe. Check and remove the rust on the steel tube. Secondly, make the corrosion pipe sleeve in the polyethylene sleeve, through the pipe forming. However, through the head repair, polyurethane foam is injected into it, and the voids are fully filled to make it fully filled. Inspection of anti-corrosion steel pipe, inspection of finished steel pipe insulation products.