Heat treatment

Automazione Veneto, with its qualified personnel, carries out heat treatments, both in production and repair, on industrial piping and the related welds performed on them, as well as on structural steelwork subjected to significant stress and fatigue.

The PWHT process (Post Weld Heat Treatment – commonly known as “stress relief heat treatment”) is used in sectors such as oil & gas, petrochemical, power generation, and structural construction, to improve mechanical properties and reduce residual stresses in the “weld joint.” It involves heating the component in the area where welds have been made to a specific temperature, holding it at that temperature for a certain period of time, and finally subjecting it to a controlled cooling process.

The purpose of PWHT is to relieve residual stresses introduced during welding due to the high heat input required for fusion of the welded parts, which can cause distortions or cracks in the component. It also helps to refine the microstructure of the weld area, improving toughness and reducing susceptibility to brittle fracture (increasing resilience).

The specific temperature and duration of PWHT depend on factors such as the type of material, thickness, welding process used, and the desired mechanical properties. The process is generally carried out after welding is completed but before any final machining or surface treatment is applied.