Polyurethane insulation pipe, also known as directly buried insulation pipe, is composed of working pipe, insulation layer, and polyethylene sheath. The working pipe of polyurethane insulation pipe can be seamless, straight seam, or spiral steel pipe. The medium conveyed inside is high-temperature water, and the insulation temperature is maintained at 150 ℃. Because polyurethane will carbonize when exposed to a working environment exceeding 150 ℃ for a long time, it will affect the insulation effect and the service life of the working pipe. The insulation layer of polyurethane insulation pipe is a rigid polyurethane foam insulation layer. Polyethylene leather covers come in three colors: black, yellow, and red. Yellow is the basic color, while black is the color after adding a mixture and solidifying. Polyurethane insulation pipes are more commonly buried, with a insulation temperature difference of 400 ℃ from steel sleeves.
Foamed polyurethane insulation pipe is composed of two components, A component is polyol, and B component is isocyanate. During construction, the two components are mixed into a prepolymer in the foaming machine, and then water, catalyst, surfactant, and other additives are added to the prepolymer. The final product of foaming is mixed under high-speed stirring, forming a mist shape and foaming solidification in one minute. Fast hardening speed after foaming, firm and aging resistant after hardening; After molding, it achieves good insulation, waterproofing, and bonding performance, and is currently widely used. Small thermal conductivity coefficient of polyurethane: the thermal conductivity coefficient of polyurethane foam in thermal insulation materials is relatively low, which can lower the heat loss of materials, and prevent corrosion, water and aging. Because the closed cell rate of polyurethane foam has reached more than 92%, the foamed polyurethane insulation pipe can effectively prevent water and play the role of heat preservation and insulation. The infiltration of moisture and other corrosive liquids and gases can prevent the growth and development of microorganisms.
