The Spray Winding Insulation Pipe Equipment is an automatic production line designed for manufacturing "polyurethane spraying + polyethylene winding" insulation pipes. This advanced system specializes in producing large-diameter, high-density, and high-performance prefabricated direct-buried insulation pipes, widely utilized in long-distance thermal power, chemical industry, and municipal heating projects.
The polyurethane spraying system operates with precision: the steel pipe rotates and moves forward at a constant speed while the spray gun uniformly applies liquid polyurethane (PU) to the outer wall. The material foams and solidifies instantly, forming a consistent insulation layer.
Surface preparation through shot blasting or sand blasting removes rust and ensures a clean surface free of oil and impurities. Preheating follows to optimize polyurethane adhesion during foaming.
High-pressure foaming machine mixes polyurethane raw materials and sprays them evenly onto the preheated steel pipe surface, where they rapidly foam to form the insulation layer.
Polyethylene (PE) material is wrapped around the polyurethane insulation layer to form the outer protective sheath. Cooling and shaping ensure tight bonding between layers.
Insulation pipes are cut to required lengths according to customer specifications. End trimming ensures flat surfaces for subsequent installation and connection.
Jacketed Pipe Insulation Pipe (commonly known as "pipe-in-pipe") represents the traditional approach: first extruding the PE outer protective pipe, then sleeving it over the steel pipe, and finally pouring PU foam into the middle cavity to create the three-layer "steel pipe + PU + PE" structure.
Qingdao Huashida Machinery Co., Ltd., established in 2003, has specialized in plastic pipe production lines, 3LPE anti-corrosion processing lines, and joints for plastic pipes & 2PE/3PE pipes for over 15 years. As private high-tech enterprises integrated by R&D, manufacturing, sales, service, and trading, we maintain strong collaborations with Tsinghua University, Beijing University of Chemical Technology, South China University of Technology, and other research institutions. By absorbing advanced domestic and international technologies, we have become one of China's top manufacturers of plastic extrusion machines, particularly renowned for PE insulation jacket pipe extrusion lines, 3PE anti-corrosion processing lines, and PE hollow wall spiral pipe production lines.