Standard specifies requirements for gases used in fusion welding and allied processes. Covers tungsten arc, gas-shielded metal arc, plasma arc welding and laser welding. Gas purities and mixing tolerances specified by supplier, not at point of use
First patented in 1935, requires continuous feed of consumable electrode. Molten weld protected by granular fusible flux blanket. Current ranges from 300 to 2000 A, up to 5000 A with multiple arcs
Heat input is critical parameter for consistent weld quality. Calculation uses current, voltage and travel speed. European system includes thermal efficiency parameter. Heat input typically given in kJ/mm, converted to J/mm by dividing by 1000
PQR is a record of welding variables used during qualification test. Includes destructive testing to validate mechanical properties. Used to write WPS after passing testing requirements
Studs must be designed for automatic timed welding with arc shields. Arc shields and flux required for studs 5/16" diameter or larger. Stud bases must pass qualification test according to Annex IX. Studs must be made from cold-drawn bar stock conforming to ASTM A 108
Carbon equivalent (CE) measures material weldability based on chemical composition. Common formulas include IIW-CE and PCM-CE based on various alloying elements. Calculation considers carbon, manganese, silicon, chromium, molybdenum, and nickel