Polyurethane Insulation Pipe, full name: High-Density Polyethylene Plastic Outer Sheath Pre-fabricated Direct Burial Insulation Pipe with Polyurethane Foam Insulation Layer, which is sequentially combined outwardly from the working steel pipe conveying the medium, the polyurethane insulation layer, and the polyethylene plastic outer sheath.

National standard polyurethane-insulated steel pipes have a three-layer structure from the inside out.

Layer 1: Working钢管Layer - Generally, seamless pipes (GB8163-87), spiral-welded pipes (GB9711-88; SY/T5038-92), and straight seam welded pipes (GB3092-93) are selected according to design and customer requirements. After being processed by advanced shot blasting rust removal technology, the surface of the steel pipes can reach Sa2 grade of GB8923-1988 standard, and the surface roughness can reach R=12.5 micrometers according to GB6060.5-88 standard.

Second Layer: Insulation made of polyurethane foam, which is a solid polyurethane foam plastic raw material, injected once into the cavity between the steel pipe and the outer sheath using a high-pressure foaming machine. This is commonly referred to as the "pipe-in-pipe foaming process." Its functions include: 1) waterproofing, 2) thermal insulation, and 3) supporting the weight of the heat network. For conveying media temperatures ranging from -50℃ to 120℃, use rigid polyurethane foam plastic as the insulation layer.

Three Layers: High-density polyethylene protective layer, pre-made black (yellow) plastic pipes with specified wall thickness. Its functions are: 1. To protect the polyurethane insulation layer from damage by mechanical hard objects, and 2. To prevent corrosion and water damage.

Product Structure: The prefabricated buried steam insulation pipe consists of a core tube (working steel pipe), a reducing layer, an insulating layer, a reflective layer, a fastening steel strip, a sliding bracket, an air layer, an outer steel pipe, sprayed polyurethane, and wrapped glass fiber reinforced plastic.

Features:

The outer protective layer made of steel pipes offers high strength and is not easily damaged, capable of withstanding significant upper loads. To ensure a long lifespan, anti-corrosion treatment is required for the steel jacket pipe.

The rolling support structure design is rational, featuring minimal rolling friction, reduced load on the fixed support, and a simple mechanical analysis principle, significantly enhancing the stability and safety of the pipeline.

The vacuum layer completely eliminates thermal conduction and convection through air layers, reducing heat loss. Compared to an air layer structure, it can lower the outer wall temperature by 8-13°C under the same insulation thickness.

The vacuum-packing device completely resolves the problem of corrosion to the inner wall of the outer steel casing from hot and humid air, significantly enhancing the service life of directly buried steam pipelines. The product lifespan is extended to 30 years.