Heat Treatment Services
Post Weld Heat Treatment (PWHT) services to relieve residual stresses, improve mechanical properties, and ensure compliance with code and project requirements.
Professional PWHT for Critical Applications
JST Group provides professional heat treatment services for industrial and construction applications throughout Thailand and Southeast Asia. Our experienced heat treatment engineers and technicians are equipped with the latest multi-channel data logging technology and certified equipment to deliver safe, precise, and reliable results on every project.
Post Weld Heat Treatment is critical in the fabrication and maintenance of pressure vessels, pipelines, and structural components. PWHT relieves residual stresses introduced during welding, improves ductility in the heat-affected zone, and ensures the finished weld meets mandatory code requirements for service.
Code Compliant
ASME, AWS D1.1, BS EN ISO 17663
Precise Temperature Control
Multi-zone electrical resistance heating
Data Monitoring & Reporting
Digital loggers with full time-temp charts
Quality Assurance
Certified procedures, third-party verification
Why PWHT Matters
Post Weld Heat Treatment is not optional — it is a mandatory code requirement for many welded joints. Done correctly, it protects both safety and asset longevity.
Stress Relief
Relieves residual stresses from welding, reducing the risk of stress corrosion cracking and hydrogen-induced failures in service.
Improved Mechanical Properties
Restores ductility and toughness in the heat-affected zone (HAZ) — critical for pressure-retaining components.
Code Compliance
Meets mandatory PWHT requirements under ASME Section VIII, AWS D1.1, PCC-2, and project-specific welding specifications.
Extended Service Life
Protects long-term integrity of pressure vessels, piping systems, and structural welds against premature failure.
Industry Applications
Oil & Gas Pipelines
Field girth welds, tie-ins, and repair welds on cross-country and subsea pipeline systems.
Refineries & Petrochemical
Pressure vessels, heat exchangers, columns, and piping within operating and turnaround environments.
Power Generation
Boiler tubes, steam piping, turbine casings, and high-energy piping systems.
Structural & Fabrication
Heavy steel fabrication, offshore structural nodes, and modular construction welds.
Full-Scope Heat Treatment
From pre-heat through PWHT to hydrogen bake-out — our teams handle the full scope of field and shop heat treatment services with modern equipment and code-compliant procedures.
- Post Weld Heat Treatment (PWHT)
- Pre-heat treatment for welding operations
- Stress relieving of fabricated components
- Local PWHT for in-situ repairs and tie-ins
- Electrical resistance heating systems
- Exothermic heating for field applications
- Heat treatment of pressure vessels and piping
- Hydrogen bake-out procedures
- Hardness testing and verification reporting
- Compliance with ASME, AWS, BS EN ISO, and NACE standards
System Overview
Related Services
- Coating Services PWHT often precedes protective coating application
- Survey & Inspections Hardness testing and NDE verification after PWHT
- Corrosion Control Heat treatment as part of corrosion management programs
Service Delivery Process
From procedure development to final documentation — a controlled, code-compliant process on every project.
Procedure Development
Review of WPS, material certificates, and code requirements to define heat treatment parameters — heating rate, hold temperature, hold time, and cooling rate.
Equipment Setup
Installation of electrical resistance heating elements, thermocouples, and insulation — with multi-channel data loggers connected and verified.
Heat Treatment Execution
Controlled heating, soaking, and cooling per approved procedure with real-time monitoring and operator supervision throughout the cycle.
Reporting & Documentation
Comprehensive records including time-temperature charts, thermocouple location diagrams, hardness results, and compliance certificates.
Need Heat Treatment for Your Project?
Our PWHT engineers are ready to discuss your requirements — from single weld joints to full pipeline stress relief programs.