Get PWHT INSTRUCTION SHEET

PWHT is required where there is a risk of environmentally-assisted cracking. PWHT of C-Mn steels is typically carried out at approximately 600°C, for one hour per 25mm of thickness.

Post Weld Heat Treatment (PWHT), or stress relief as it is sometimes known, is a method for reducing and redistributing the residual stresses in the material that have been introduced by welding.

1) AB: Rate of heating: In WPS it is mentioned as a maximum value. In the graph the rate of heating is the slope of the curve AB. So the value of the slope should not be more than the value in WPS. slope = 80 / (1/2) = 160DegC/hr ; So in this graph the rate of heating is 160DegC/hr.

PWHT is required where there is a risk of environmentally-assisted cracking. PWHT of C-Mn steels is typically carried out at approximately 600°C, for one hour per 25mm of thickness.

Post weld heat treatment (PWHT) is a controlled process in which a material that has been welded is reheated to a temperature below its lower critical transformation temperature, and then it is held at that temperature for a specified amount of time.

Post-heating is done to avoid delayed cracking in the weld. PWHT that is known as a post weld heat treatment is performed on the completed weld to relieve the stress from the weld joint. This will soften the heat affected zone and reduce the hardness of the weld.

In order to ensure the material strength of a part is retained after welding, a process known as Post Weld Heat Treatment (PWHT) is regularly performed. PWHT can be used to reduce residual stresses, as a method of hardness control, or even to enhance material strength.

Post Weld Heat Treatment (PWHT), or stress relief as it is sometimes known, is a method for reducing and redistributing the residual stresses in the material that have been introduced by welding.