Methods of Pipes Manufacture

The pipe is manufactured by one of the following processes:

• Seamless (SMLS) pipe is made by a process that does not involve welding at any stage of production.

  
  

• Welded (WLD) pipe is made using an automatic welding process with no addition of filler during the welding process.

  
  

• Heavily cold-worked (HCW) pipe is made by applying cold working of not less than 35% reduction in thickness of both wall and weld to a welded pipe prior to the final annealing. No filler is used in making the weld.