heat-forging

Post Weld Heat Treatment

Harchris Heat Treatment specializes in performing post weld heat treatment for the steel and metal fabrication industries in South Africa, including the construction of pressure vessels, pressure piping, storage tanks, buildings, bridges, offshore platforms, power plants, etc.

There is often a mandatory requirement for post welding heat treatment due to compliance with welding codes and specifications on certain materials including but not limited to carbon steels, stainless/high alloy steels and work hardened steels. There may also be post weld heat treatment requirements based on the wall thickness of the arts being welded together.

Post weld heat treatment reduces or redistributes the residual stress introduced by the welding process with a technique that involves heating, soaking and cooling the weldment/machined surface to controlled temperatures. This improves the properties of the weldment surface.

Benefits of post weld heat treatment:

  • Improved ductility of the material
  • Improved or reduced hardness
  • Reduced risk of brittle fracture
  • Relaxed thermal stress
  • Tempered metal
  • Removal of diffusible hydrogen
  • Improved metallurgical structure