PWHT – Post Weld Heat Treatment
About PWHT
Post Weld Heat Treatment (PWHT) is a controlled thermal treatment carried out after the welding process. The welded component is heated, maintained at a specified temperature and then cooled under controlled conditions.
The primary purpose of PWHT is to relieve residual stresses generated during welding. It can also help improve ductility and toughness while reducing hardness in the welded area.
PWHT is commonly associated with critical industrial equipment such as boilers, pressure vessels and pipelines, where controlled post-weld heat treatment is important for the component’s performance.
PWHT Process
Applications
- Boilers : Applied to suitable welded boiler components.
- Pressure Vessels :Used for critical welded pressure-vessel applications.
- Pipelines : Applied to suitable pipeline welding applications.
Key Benefits
Why PWHT Matters
Residual Stress Relief
Helps relieve residual stresses created during welding.
Improved Ductility & Toughness
Can improve the ductility and toughness of the material.
Reduced Hardness
Helps reduce hardness in the treated welded area.
Technical Control
Controlled Temperature as a Function of Time
PWHT requires controlled temperature management throughout the heating, soaking and cooling stages. The temperature is monitored as a function of time to maintain the required heat-treatment cycle.
This controlled approach supports consistent execution of the PWHT process.
PWHT at LOHITHA Services
Professional Heat Treatment Solutions
LOHITHA Services provides heat treatment capabilities including Preheating, Post Heating and PWHT for industrial applications.
Our service approach focuses on quality, safety, accuracy and timely execution, supporting the requirements of critical industrial projects.
Recent Services
- Inspection & Consultancy
- Thickness Gauging
- Boroscopy Inspection
- Hardness Testing
- Positive Material Identification
- RT – Radiography Testing
- Post Heating
- Preheating
- DPT – Dye Penetrant Testing
- Vacuum Box Testing
- MPT – Magnetic Particle Testing
- UT – Ultrasonic Testing
- PAUT – Phased Array Ultrasonic Testing
Our Brochures
HOW CAN WE HELP ?
Are you interested in finding out more of this service.