Helical two-step process

Back in 1986, we were the first manufacturer to use the helical two-step (HTS) process, and we have been continuously improving it ever since.

The big difference to conventional helical welding is the separation of the process into two steps:

Pipe shaping and continuous tack-welding

External and internal submerged-arc welding
on separate stands

The advantages of HTS technology

•  Production steps similar to longitudinally welded pipe production
  • Up to 100 % ultrasonic testing of the hot wide strip before pipe forming
  • Strip edges are trimmed and milled
  • Strip edge is crimped before pipe forming
• High process efficiency
  Pipe shaping and tack-welding at 15 m/min makes for high productivity
• Minimum defect rate
  No submerged-arc welding defects thanks to continuous pipe forming without start-stop interruptions.

In addition, there is no restriction to standard diameters, because the HTS welding process allows pipe inside and outside diameters to be tailored to individual requirements.