Welding Heat Input
Arc energy from volts, amps, and travel speed (the ASME IX / AWS D1.1 heat input) with a WPS pass/fail on it.
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 (ASME IX / AWS D1.1 heat input) 37500 J/in
- EN 1011-1 heat input (k-factor) 30
Checked against published worked examples from: AWS D1.1 / ASME BPVC Section IX (by name).
Details, formula, and sources
ScopeArc energy from volts, amps, and travel speed (the ASME IX / AWS D1.1 heat input) with a WPS pass/fail on it, plus the EN 1011-1 heat input in kJ/in and kJ/mm with the process arc efficiency.
Formula or tableArc energy = (60 * V * I) / TS (J per unit length), the ASME IX QW-409.1 / AWS D1.1 heat input; the WPS range is checked against arc energy / 1000 (kJ per unit length). EN 1011-1 heat input = arc energy * k / 1000, with k by process: 0.8 SMAW/GMAW/FCAW, 0.6 GTAW, 1.0 SAW (user-editable), reported separately. kJ/in to kJ/mm via x 0.0394.
Source and editionAWS D1.1 Structural Welding Code and ASME BPVC Section IX QW-409.1 heat-input definition HI = (60*V*I)/TS with no efficiency factor, by name; the per-process arc-efficiency (k) factors are EN 1011-1 / ISO/TR 17671 and apply only to the EN 1011-1 figure.
Free accessFree overviews at aws.org. The governing WPS/PQR ranges are user-supplied.
What governsEstimate. Engineer of record governs the design and acceptance. Verify against the project structural drawings and the manufacturer's published capacity / chart.
API field namesprocess, 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-editable; EN 1011-1 figure only, not the WPS checkEN 1011-1 / ISO/TR 17671 k-factors