Polyurethane (PU) Insulation Material is a rigid foam produce by the reaction of isocyanate and polyol, serving as the core component of prefabricated directly buried insulated pipes. It features extremely low thermal conductivity, minimizing heat loss or gain in pipeline systems. The material is inject between the central steel pipe and the outer polyethylene casing in the factory, where it foams to form a continuous, seamless, and tightly bonded insulation layer. It offers excellent thermal performance, high mechanical strength, and good waterproofing. It is the ideal choice for district heating & cooling networks and insulated oil pipelines.