Stress Relief Heat Treatment

Massive Post-Weld Heat Treatment (PWHT)

Heavy welding introduces intense, localized thermal energy into steel structures. As the weld cools and contracts, it locks enormous residual stresses into the assembly. If left untreated, these stresses cause extreme distortion during CNC machining, promote stress-corrosion cracking, and severely compromise the fatigue life of the equipment.

Openex mitigates this using world-class Thermal Stress Relief and Post-Weld Heat Treatment (PWHT). Utilizing our massive on-site car-bottom furnaces, we successfully heat treat single assemblies weighing up to 250 tons in one continuous cycle, ensuring the entire structure relaxes evenly into a perfectly stable state.

Thermal Engineering Advantages

Colossal Car-Bottom Furnaces

Splicing components because they don't fit in the oven compromises structural integrity. Our flagship natural gas car-bottom furnace measures approximately 20m (L) x 8m (W) x 6m (H). It is easily capable of taking an entire massive rotary kiln section or towering press frame, supporting load weights exceeding 200 tons.

Computerized Multi-Zone Charting

In heat treatment, ramp rate and holding times are dictated by strict ASME engineering codes based on plate thickness. Our furnaces utilize fully computerized, multi-zone atmospheric control. We attach dozens of calibrated thermocouples directly to the workpiece, mapping and charting the specific metal temperature across the entire part to prevent warping or micro-fractures during cooling.

Guaranteed Pre-Machining Stability

Machining "raw" weldments creates spring-back—the geometry shifts mid-cut as internal tension is released, destroying tolerances. Because Openex handles PWHT entirely in-house directly prior to hitting our massive gantry mills, we ensure a "dead-soft", uniform grain structure, allowing us to machine massive flanges and beds to nanometer tolerances without distortion.

Thermal Treatment Capabilities

We process a wide array of steel structures under strict global code compliances, supported by verifiable documentation generated natively during every heating cycle.