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PE insulated pipe is composed of outer HDPE high-density polyethylene pipe, intermediate polyurethane foam insulation layer and inner PE pipe.

Part 1: Outer layer (outer protective tube)

The outer protective tube is the outer layer of the insulation layer to prevent damage and influence from external forces and the environment on the insulation material. The outer protective pipe of high-density polyethylene (HDPE) is made of HDPE and manufactured using advanced equipment and processes. The product quality complies with GB/T13663-2000 and GB/T29047 standards. Polyethylene outer protective pipes have the characteristics of high mechanical strength, impact resistance, environmental stress cracking resistance, corrosion resistance, low temperature resistance, simple structure, and leak free sealing. The service life is 50 years.

Part 2: Intermediate layer (polyurethane insulation)

The insulation layer is located between the working pipe and the outer pipe, and is an insulation material layer that maintains the temperature of the medium transported by the pipeline. The insulation layer is made of rigid polyurethane foam, which can fully fill the gap between the PE-RT-II pipe and the sleeve, and has a certain bonding strength to prepare heat-resistant polyethylene. (PE) forms a whole between the pipe, shell, and insulator. Polyurethane directly buried thermal insulation foam has good mechanical properties and thermal insulation properties. In general, it can withstand a temperature of 120 degrees Celsius, and can also be modified or combined with other insulation materials to withstand a temperature of 180 degrees Celsius.

Part 3: Inner layer (working pipe PE pipe):

A work pipe is a pipe used to transport media in insulated composite plastic pipes. It should comply with the provisions of GB/T28799.2-2012. PE pipe is a heat-resistant polyethylene pipe from France. PE-RT-II pipes made of high-density polyethylene and hexene copolymers have excellent long-term hydrostatic strength without crosslinking. Connections and all welding methods can be used. PE pipes not only have corrosion resistance that cannot be compared to steel pipes, but also have the advantages of easy connection, good interface sealing, and long service life.