Oxy-Fuel
Plasma
Laser
Sawing
Concentricity tolerances are held within 0.8 mm/m per ANSI/ASME B16.9. Tack welds are applied at 10 mm thickness using GTAW with matching filler wire, executed by AWS-certified welders. Spool geometry is validated with digital theodolites prior to full welding to prevent misalignment-induced stress concentrations.
Welding adheres strictly to WPS documentation. Root passes utilize GTAW with argon backing gas for full penetration. Subsequent fill/cap passes employ SMAW or FCAW, maintaining interpass temperatures at 150°–250°C. Critical spools undergo stress-relieving per ASTM E2935 when thickness exceeds 25 mm or for P-No. 1 materials under cyclic service.
