Polyurethane Foam District Heating Steel Pipe


Standards: EN/DIN 253, EN 448, EN 489;

Inner pipe Material: API 5L Gr. B X42 X46 X52 X56 X60.

ASTM A106/53 Gr. A /Gr. B / Gr. C

APL 5CT J55, K55, N80, L80, C90, T95, P110

Polyurethane foam insulated steel pipe also referred to as urethane foam pre-insulated piping, PU district heating pipes is the insulation pipe with rigid polyurethane foam plastic as its insulation material, made of inner carrier steel pipes, middle rigid polyurethane foam insulation layer and outer protective layer. It offers high-performance systems capable of carrying liquids at controlled temperatures ranging from -350° F to +250° F with urethane foam uniformly fills the space between the carrier pipe and jacket, are used to transport of liquids and gases with temperatures ranging from -200°C to 250°C.

Insulation materials layer

Rigid polyurethane foam is injected into the cavity between the steel tube and the outer layer by a high-pressure foaming machine. Polyurethane foam has good mechanical and adiabatic properties and can withstand high temperatures to 120℃. It can withstand 180℃ through modification or combination with other heat insulation materials. The material can be: For keeping cold(-200℃∼120℃) Polyurethane foam; For keeping warm (120 ℃∼300℃) Polyurethane foam+ Silica (mineral wool)

Outer casing pipe

Prefabricated black or yellow polyethylene plastic pipe can protect the polyurethane insulation layer from mechanical damage, anti-corrosion, waterproof. The material can be HDPE pipe (for underground/ above ground) or Glass fiber reinforced plastics pipe.


  • EN/DIN 253
  • EN 448
  • EN 489

Pipe Specifications

Size ERW/LSAW:Ф25-Ф630mm,length: 6m.

SSAW:Ф219mm-Ф3620mm, length:12m.

SMLS : 10.3-1020mm * 2mm-40mm(1/4”- 40”)

WT: 1.24mm – 60mm (SCH10-SCH160)

Length: 5.8M; 6M; 11.8 M, 12M or as customer’s requirement

Inner pipe Material API 5L Gr. B X42 X46 X52 X56 X60.

ASTM A106/53 Gr. A /Gr. B / Gr. C

APL 5CT:J55, K55, N80, L80, C90, T95, P110

Coating Thickness The outer 2.0-4.0 mm, and the inner 0.35-0.5 mm

As one of the leading suppliers and manufacturers of coating carbon steel pipe in China, WLD steel supply and manufacture high-quality pre-insulated steel pipes in accordance with EN/DIN 253 standards, specified delivery conditions and final customer specifications for industrial and commercial applications. Special sizes of steel pipes and delivery issues can be further negotiated and we provide a wide range of solutions for purchasing departments to select alternative grades without specifying product specifications. With the partnership of the major steel mills in China, comprehensive advanced coating measures are provided for your pipe needs.