Rigid Polyurethane Foam is a professional cryogenic insulation material. It is mainly made from polyether polyols plus isocyanate added with flame retardant, foaming agent and stabilizing agent and it changes into foaming body through chemical reaction after mixed and stirred. It has high rate of closed cells and low water absorption. As a result, it is usually used as cold insulation and heat preservation at low temperatures. Consequently, it is widely used in industries of petroleum, chemical engineering, ethylene, refrigerated warehouse, food storage, partition wall and wallboard in family refrigerator and architecture industry. It can be prefabricated into slab or pipe, or be foamed on site