Preheating and Post-Weld Heat Treatment (PWHT) Services
At High Technology Nondestructive Testing Service Co., Ltd, we understand that high-quality welding is about more than just a clean bead—it is about managing the internal stresses and metallurgy of the metal. Our specialized Heat Treatment services ensure that your welded components achieve maximum strength and durability while minimizing the risk of cracking.
Our Thermal Processing Capabilities
1. Preheating Services
We provide controlled preheating to reduce the cooling rate of the weld zone, preventing the formation of brittle microstructures and hydrogen-induced cracking (HIC).
-
Uniform Heat Distribution: Utilizing advanced electrical resistance heating or induction methods.
-
Precision Monitoring: Real-time temperature tracking using calibrated thermocouples to ensure compliance with WPS requirements.
2. Post-Weld Heat Treatment (PWHT)
For heavy-wall pressure vessels, piping, and structural steel, PWHT is critical to “relax” the residual stresses locked in during the welding process.
-
Stress Relieving: Reducing internal tension to prevent premature fatigue or stress corrosion cracking.
-
Hardness Reduction: Improving the ductility and toughness of the Heat Affected Zone (HAZ).
-
On-Site Execution: Our mobile heat treatment units are equipped to handle complex geometries and large-scale projects directly at your facility or construction site.
Technical Compliance & Equipment
-
Code Adherence: All heat treatment cycles are performed in strict accordance with ASME Section VIII, ASME B31.3, AWS D1.1, and other international standards.
-
Digital Documentation: We provide clients with detailed Time-Temperature Charts, offering full traceability and proof of compliance for audit purposes.
-
Safety & Efficiency: Our technicians are trained to manage high-temperature environments safely, utilizing high-grade insulation and automated control systems to optimize energy use and project timelines.
The “Total Quality” Advantage
By combining our Heat Treatment services with our NDT expertise, HTNDT offers a seamless workflow. We can preheat, supervise the weld, perform PWHT, and conduct final NDT inspections—providing a single point of accountability for your project’s mechanical integrity.
