PU Insulated Pipe

Polyurethane (PU) insulated pipe, also known as pre-insulated pipe or PU foam pipe insulation, is a composite system designed to minimize heat loss or gain during fluid transportation. By combining a steel carrier pipe, high-performance polyurethane foam insulation, and a protective outer jacket, it achieves excellent thermal efficiency, corrosion resistance, and mechanical durability. PU insulated pipes are extensively used in district heating & cooling networks, oil & gas pipelines, and industrial process systems, where energy saving and long-term service life are critical.

A typical PU insulated pipeline consists of three integral layers:

• Carrier Pipe: Usually carbon steel, stainless steel, or ductile iron, built to withstand internal pressure and fluid transport requirements.
• Polyurethane Foam Insulation: A rigid, closed-cell foa
• Outer Jacket / Casing: High-density polyethylene (HDPE), galvanized steel, or fiberglass-reinforced plastic (FRP) to protect against mechanical impact, corrosion, UV exposure, and moisture ingress.

This layered structure ensures pipelines retain fluid temperature while remaining mechanically robust and resistant to harsh installation or environmental conditions.

• Pipe Preparation: Carrier pipe cleaned, blasted, or primed to ensure proper bonding.
• Assembly: Outer jacket positioned concentrically around the steel pipe with spacers.
• Foam Injection: Polyol and isocyanate mixed under high pressure and injected into the annular gap.
• Expansion & Curing: PU foam expands to fill the void, adheres firmly to steel and jacket, then hardens into a rigid insulation layer.
• Quality Control: Insulation density test, adhesion checks, thermal conductivity measurement, cutback finishing, hydrostatic test, and dimensional inspection.

• High Thermal Efficiency: Very low heat transfer coefficient; reduces energy loss by up to 40–60% compared with bare steel pipe.
• Durability: Long service life (≥30 years) thanks to rigid foam in
• Corrosion Protection: Outer casing shields against soil moisture, chemicals, and UV exposure.
• Mechanical Strength: Withstands soil loads, han
• Versatile Applications: Suitable for direct-buried, aboveground, and underwater pipeline systems.
• Cost Saving: Reduced heat loss translates to significant long-term operational energy savings.

• Foam Density: 60–80 kg/m³
• Thermal Conductivity: ≤0.030 W/m·K
• Operating Temperature: -50°C to +140°C (short-term up to 150°C)
• Outer Jacket: HDPE / Steel / FRP
• Pipe Sizes: DN 25 – DN 1200 (1″ – 48″), custom available
• Service Life: ≥30 years

• District heating and cooling pipelines
• Oil & gas transportation requiring thermal stability
• Chemical & process plant piping
• Cold climate water distribution networks
• Industrial HVAC and refrigeration systems

• Advanced foaming technology for uniform insulation density.
• Flexible jacket options 
• International standard compliance for carrier pipe and insulation.
• Complete QA/QC documentation including thermal and mechanical performance data.
• Proven project record in heating networks, offshore oil pipelines, and industrial projects.

• System: Steel pipe + PU foam + outer jacket
• Foam Density: 60–80 kg/m³
• Thermal Conductivity: ≤0.030 W/m·K
• Operating Temp: -50°C to +140°C
• Size Range: DN25–DN1200
• Applications: District heating/cooling, oil & gas, industrial, refrigeration

Certifications

 

CE Certificate

ISO 9001 Certificate

API Q1 Certificate

ABS Certificate

AP-5L Certificate

API-5CT Certificate

 

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