Offshore platforms and wind turbines are getting bigger and bigger. The use of steel makes it possible to install these huge structures at sea.

Extra strength is obtained by using round shapes in steel. This is where Kersten comes in. We have an extensive track record in the production of tubulars with customer-specific dimensions for offshore energy structures. Besides tubulars in standard materials such as S355, Kersten specialises in the production of tubulars in high-strength steels such as S460 and S690.
Kersten produces Tailor-made spudpiles, pinpiles, pile sleeves and parts of foundation legs and bracings.

Tubular factsheet


For the production of tubulars, Kersten has a special production line. Here, plates up to 150 mm thick are cut to size using plasma or oxyfuel cutting technology. Weld edges are applied in the same process. The plates are then rolled into cylinders. The longitudinal seams are welded according to the latest and strictest offshore standards, inspected and tested. The cylinders are assembled on the tubular production lines, where the circumferential seams are welded with multi-wire submerged arch welds.
If required, the tubulars are fitted with weld beads, grout seals, shims, reinforcement rings, brackets, cut-outs, etc.


  • Wall thicknesses up to 150 mm
  • Diameters up to 5.8 metres
  • Weights up to 100 tonnes (per section)
  • Lengths up to 40 metres (per section)
  • Materials: S355, S460, S690QL and more


  • Co-engineering
  • Cutting plates to size and welding edge preparation 
  • Rolling of steel plates into cylinders
  • Longitudinal seam welding
  • Circumferential seam welding
  • (3D) cutting to fixed lengths, machining and 3D finishing.
  • Production and assembly of attachments, such as cones, shims, reinforcement rings, etc.
  • Surface treatment
  • Delivery on site


  • SAW (121) (Twin)
  • MIG-MAG (135-136)
  • TIG/WIG (141)


  • EN 1090 EXC 4
  • EN-ISO 3834 - 2
  • DIN 18.800-7 class E (Grosser Eignungsnachweis)
  • Welding method qualifications according to ASME and EN 15614 -1, NORSOK, EMUA, DNV, etc.

Offshore track record