Welding Heat Input
Heat input in kJ/in and kJ/mm from volts, amps, travel speed, and arc efficiency, with WPS pass/fail.
Example
You enter
- Process SMAW
- Voltage (V) 25
- Current (A) 200
- Travel speed (in/min) 8
- Arc efficiency (0-1) 0.8
You get
- Arc energy 37500 J/in
- Heat input 30
Details, formula, and sources
Arc energy = (60 * V * I) / TS (J per unit length); heat input HI = arc energy * efficiency / 1000 (kJ per unit length). Arc efficiency defaults by process: 0.8 SMAW/GMAW/FCAW, 0.6 GTAW, 1.0 SAW (user-editable). kJ/in to kJ/mm via x 0.0394.
AWS D1.1 Structural Welding Code and ASME BPVC Section IX heat-input definition HI = (60*V*I)/TS, by name, with the arc-efficiency factor by process.
Free overviews at aws.org. The governing WPS/PQR ranges are user-supplied.
Estimate. Engineer of record governs the design and acceptance. Verify against the project structural drawings and the manufacturer's published capacity / chart.
Field names used by the API: process, voltage_V, current_A, travel_in_min, efficiency, arc_energy_j_in, heat_input_kj_in
- Arc efficiency process default 0.6 to 1.0, user-editableAWS/ASME process convention