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Composition of polyurethane foam insulation steel pipe wholesale price

Polyurethane foam insulation pipe wholesale price from inside to outside pipeline insulation pipe three layer structure: seamless pipe is generally based on customer design and spiral welded pipe and longitudinal welded pipe surface requirements of advanced shot blasting rust treatment, steel pipe derusting grade reaches Sa2 level standard, R = 12.5 micron surface roughness can achieve the standard. Pipe insulation polyurethane insulation layer: high pressure foam machine is used to inject rigid polyurethane foam between the steel tube and the outer cavity. This is called tube foaming process. Its effect is waterproof, thermal insulation, and supporting the weight of the heat network. When the conveying medium temperature is selected: rigid polyurethane foam plastic as insulation layer. Pipeline insulation high density polyethylene protective layer: Prefabricated thickness of black (yellow) plastic. The function of the pipe is to protect the polyurethane insulation layer from mechanical hard damage and anti-corrosion and waterproof Thermal insulation materials can be used for thermal insulation, improve living comfort, and contribute to energy conservation and emission reduction. Do not underestimate the development goal of thermal insulation materials for energy conservation and emission reduction. The contribution rate of building energy conservation reaches 20%, that is to say, 120 million tons of standard coal is saved. Of course, all these need to be built on the premise of safety and reliability. Thermal insulation materials can be laid on the inner wall, but in practical application, the thermal insulation effect is not ideal, Insulation is usually placed inside the exterior wall The commercial exterior wall thermal insulation materials mainly include polystyrene board, extruded plate and polyurethane foam. The first two materials used earlier than polyurethane foam. Some buildings still use this material. Compared with polystyrene and extruded plate, polyurethane foam has good thermal insulation performance, good heat resistance, long service life, light weight, convenient transportation and construction, and good water resistance. The price is slightly higher. Polyurethane foam gradually takes the place of the preferred polyurethane insulation pipe in the pipe insulation material, which is much lower than that of other heat preservation pipe materials, and the insulation effect is increased by 4~9 times. The water absorption rate is very low of polyurethane foam insulation steel pipe wholesale price, about 0.2 kg / m2. The reason of low water absorption is that the closing rate of polyurethane foam is about 92%. High density polyethylene or glass fiber reinforced plastic protective shell with low thermal conductivity, low water absorption, good thermal insulation layer and good waterproof performance has changed the situation of the traditional cooking heat pipe laying "wet cotton padded jacket". The total heat loss has greatly reduced the heat loss of the heating pipe network to 2%. Less than 10% of the international standard