High density polyethylene polyurethane foam insulation tubes: a certain corrosion resistance, and has good insulation properties. Selection of second degree inorganic zinc primer (temperature ≥400 ℃) anti-corrosion coatings, pipes port selection polyethylene film or three PE cold sealing tapes, insulation material multi-layer bandaging wrong seam, effectively reducing the heat loss, while using Coat surface controls heating pipe insulation, so that the temperature control jacket coating is guaranteed. It features: low heat loss and save energy. Corrosion, good insulation properties, long service life. All kinds of pipe insulation has a particularly outstanding advantages: 1, good insulation properties of polyurethane insulation pipe black pipe insulation, heat loss is only 25% of the traditional pipe, long run can save a lot of energy air-conditioning pipe insulation, significantly reduce energy costs. 2, polyurethane insulation also has a strong waterproof and corrosion resistance, without attached trench can be directly buried in the ground or water, construction easily and quickly, and lower total cost. Polyurethane foam casting: 1.05 → measurement equipment flow → Set pouring time (feeding amount / flow): 1 adjustment foaming machine mixing ratio. HDPE pipe is completed in the middle wearing armor tube plugging the pipe ends are on location open after pouring hole → The foam machine mixing head of the nozzle is inserted into the pouring hole → casting → empty plug sealing material pouring hole → aging → disassemble card Head → test → Correct feeding amount → finished.