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1. Convenient construction, the steel pipe anti-corrosion layer is made of cast-in-place tanks or prefabrication methods, and the polyurethane pipe insulation layer is used. The method is simple and fast.

2. Low thermal conductivity, the thermal conductivity of polyurethane insulation material is the lowest among insulation materials, and it minimizes the heat loss of the material.

Because the polyurethane rigid foam insulation layer is closely combined with the outer surface of the steel pipe, it can isolate the penetration of air and water, thereby achieving a good anti-corrosion effect. At the same time, the foam pores are closed and the water absorption rate is small. High-density polyethylene casing and FRP casing have good corrosion resistance, insulation and mechanical properties. Therefore, the outer surface of the working steel pipe is almost free from corrosion by outside air and water. Generally, as long as the internal water quality of the pipeline is well treated, the service life can reach more than 50 years, which is 3-4 times that of traditional trenching and overhead laying.

Polyurethane is a high-grade insulation material with excellent performance. Generally, when polyurethane materials are used, all aspects are very strict. Because of the high price, many people use it for residential buildings.

1. Construction of ground mortar

2. Requires 160g/m2 of glass fiber mesh, and on-site inspection and functional testing of exterior wall insulation materials.

3. Polyurethane exterior wall insulation corner fixation

The insulation board should start from the wall base or a solid bracket, with an aluminum alloy bracket at the bottom. The bracket is installed horizontally from bottom to top, checking the wire and obtaining the verticality of the lead. The vertical joints between positive and negative angles should be staggered. When installing, the glue layer should be squeezed so that the insulation board has a strong bond on the outer wall. During the installation of the insulation board and within 24 hours after installation, the air temperature and surface temperature of the outer wall shall not be lower than 5°C, and the insulation board shall be arranged in the corner.