Polyurethane insulation pipe

Published:2025-06-16 | Last Updated: 2025-06-16    Views: 5

I. What is polyurethane insulation pipe?

Directly buried polyurethane insulation steel pipes are core components of modern heating systems, achieving high-efficiency insulation through a three-layer composite structure. The steel pipe layer bears pressure and prevents corrosion, the polyurethane foam layer locks in heat, and the HDPE shell resists environmental corrosion.

This design reduces heat loss to as low as 0.03W/m·K, achieving energy savings of more than 40% compared to traditional pipes.

II. Technical parameters of polyurethane insulation pipes

III. Why choose polyurethane foam insulated steel pipes?

Polyurethane has a closed cell rate of over 90%, forming a vacuum-level insulation layer. The high-density polyurethane foam steel pipe insulation structure (density 60 kg/m³) remains stable in extreme environments ranging from -50°C to 150°C, making it particularly suitable for district heating and oil transportation.

IV. What are the advantages of direct burial installation?

Direct burial polyurethane insulated steel pipes can be directly laid underground without the need to construct a pipe gallery:  

Compressive strength ≥ 200 kPa, capable of withstanding 3 meters of soil pressure.

HDPE outer shell resistant to acid and alkali corrosion, with a service life of up to 30 years.

Reduces construction time and earthwork costs by 50%.

V. How is the quality of insulated steel pipes tested?

Three key quality control measures:

① Polyurethane foam insulation pipe density testing (≥60 kg/m³).

② Vacuum sealing test (-0.08 MPa pressure maintained for 30 minutes).

③ 3D laser scanning of insulation layer uniformity (tolerance ±2 mm).

VI. What media is it suitable for?

Insulated steel pipes are perfectly suited for a variety of fluids:

(1) High-temperature steam (up to 150°C).

(2) Frozen brine (-30°C).

(3) Chemical media (corrosion resistant to pH values of 3-11).

(4) Crude oil/natural gas (anti-static design).

VII. Polyurethane insulation pipe production process:

VIII. Core Technology Highlights

High density polyurethane foam steel pipe insulation utilize a “three-proof” process:  

Waterproof: HDPE outer shell with 0.03% water absorption rate.

Heat loss prevention: λ value of 0.033 W/m·K (exceeds national standards).

Displacement prevention: 100% shear-resistant bonding between polyurethane and steel pipe.

IX. Maintenance and Lifespan

Directly buried polyurethane insulated steel pipes achieve “zero maintenance” operation:  

Cathodic protection + epoxy coating dual corrosion protection.

Expected service life of 50 years (EN 253 certified).

Vacuum integrity testing required only once every 5 years.

X. Industry Application Scenarios

Insulated steel pipes have been adopted across four major sectors:

XI. Purchasing Guide

Look for three international certifications:

Polyurethane foam insulated steel pipes must be tested for foam stability in accordance with ISO 21877.

Directly buried polyurethane insulated steel pipes must pass EN 253 weather resistance testing.

High-density polyurethane foam insulated steel pipes must be accompanied by an ASTM C177 thermal conductivity report.

More than 500,000 kilometers of insulated steel pipes are laid globally each year, with Chinese manufacturing accounting for 68% of the total.