Polyurethane Insulated Steel Pipe

Unlike prefabricated direct-buried insulated pipes specifically designed for direct burial, polyurethane insulated steel pipes can use either HDPE or fiberglass for the outer sheath, allowing for underground, trench, and overhead installations with greater flexibility in adapting to different working conditions. The product is mainly used for conveying hot water, chilled water, and low-temperature industrial media below 120℃, making it a cost-effective choice for overseas civilian heating and cooling systems and small to medium-sized industrial pipelines.

Let's first discuss its core structural design. Each layer has a clear functional role, each performing its specific function and complementing the others. The inner layer is the working steel pipe, which is also the pressure-bearing core of the entire pipeline. We can select mainstream materials such as seamless steel pipe, spiral welded pipe, and straight seam welded pipe according to project conditions, fully adapting to different pressure and diameter conveying needs. Before leaving the factory, the steel pipes undergo professional shot blasting to achieve standard rust removal levels, ensuring a tight bond between the polyurethane foam layer and the steel pipe, preventing delamination.

The middle layer is a rigid polyurethane foam insulation layer, which is also the core of the product's energy-saving performance. It has an industry standard density ≥60kg/m³, a closed-cell rate of over 92%, and a thermal conductivity as low as 0.033W/(m·K). This parameter places it among the top tier of energy-saving performance in the global insulation materials industry, minimizing heat and cold losses during the transportation of hot water and cryogenic media. Notably, its compressive strength and waterproofing are excellent; even when buried underground for extended periods in contact with damp soil, it is not prone to moisture absorption, aging, or failure, making it perfectly suited for direct underground burial environments.

The outer protective layer primarily uses HDPE high-density polyethylene, also known as the black jacket. Its function is straightforward: to isolate it from soil acid and alkali corrosion and groundwater erosion, while resisting external soil pressure and minor external damage. For highly corrosive construction environments, we can also customize fiberglass outer jacket styles to adapt to more complex overseas conditions. Furthermore, high-end customized versions can be equipped with leakage alarm lines, allowing for rapid and accurate location of faults in case of internal leaks or damage, greatly reducing the difficulty of subsequent maintenance.