Pipe-in-Pipe bonded system

The LOGSTOR Pipe-in-Pipe offshore hot applications solution consist of steel inner pipe, steel outer pipe (with corrosion protection), and PUR foam injected between the two pipes.
A bonded pipe insulation system for subsea applications.


A: Steel pipe (inner)
B: PUR foam
C: Steel pipe (outer)
D: AC coating

Product description

  • Steel inner pipe
  • Steel outer pipe with AC Coating (FBE, 3LPE, 3LPP)
  • Foam Density 100 kg/m³ (+20 / -10 kg/m³)
  • Lambda value of 0.032 W/mK
  • Operation temperature max. 140 °C
  • Achievable U-value at 0.4 – 1.5 W/m²K referenced to inner steel pipe OD

Application process

1 Steel pipe pre-heated

Steel pipe pre-heated

2 Insertion of steel pipe in the mold

Insertion of steel pipe in the mold

3 Centering and installing end tools

Centering and installing end tools

4 Injection of insulation

Injection of insulation

5 Remove end tools

Remove end tools

6 Pipe inspection ready for dispatch

Pipe inspection ready for dispatch

System main features

  • The pipes can be installed using S-lay, tow-out or J-lay methods. Standard length of each pipe is 12.2 m, can also be supplied as double-joint, or as specified by client.
  • The fieldjoints are made with steel halfshells, and backing strips are installed to ensure easy installation. This method ensures a uniform load transfer throughout the length of the pipeline.
  • Design Life is 30 years.

Plant capabilities

  • Pipe lengths typical 12 m, possibility up to 24 m
  • Pipe weight up to 20 tons
  • The range of inner steel pipe sizes is 6 – 24”
  • The outer steel pipe is 10 – 32”, depending on U-value requirements