Welding Technical Reference
All constants, parameters, and formulas used by WeldWise to estimate filler material, shielding gas, passes, equipment, and welding time.
Welding Processes
| Process | Name | Base deposition rate (kg/hr) | Process efficiency |
|---|
| GMAW | MIG (GMAW) | 3.5 | 95% |
| GTAW | TIG (GTAW) | 1.0 | 98% |
| SMAW | Stick (SMAW) | 1.5 | 65% |
| FCAW | Flux-Cored (FCAW) | 4.0 | 85% |
The base deposition rate applies at the smallest listed electrode diameter. Diameter comparisons scale this rate for informational estimates.
Material Properties
| ID | Material | Density (g/cm³) |
|---|
| Steel | Carbon Steel | 7.85 |
| Stainless | Stainless Steel | 8.00 |
| Aluminum | Aluminum | 2.70 |
Calculation Formulas
Calculations use the following geometry, filler, time, gas, and pass formulas.
| Calculation | Formula or rule |
|---|
| Groove joint area (single-sided) | depth² × tan(prepAngle ÷ 2) + (rootGap × depth) |
| Groove joint area (double-sided) | side 1 area + side 2 area, calculated independently with each side's depth and angle |
| Fillet joint area | 0.5 × legSize² |
| Area overhead | joint area × 1.10 |
| Back-gouge depth | clamp(thickness × 0.18, min=min(3, thickness × 0.5), max=min(10, thickness)) |
| Back-gouge area | 0.5 × π × gougeDepth² × (0.5 for double-sided joints; otherwise 1.0) |
| Back-gouging time (minutes) | 5 × max(0.5, thickness ÷ 10) × weldLength(m) |
| Volume (cm³) | area(mm²) × weldLength(m) × 1000 ÷ 1000 |
| Deposited filler weight (kg) | volume × materialDensity ÷ 1000 |
| Purchase filler weight | deposited filler weight ÷ fillerEfficiency |
| Arc time (hours) | fillerWeight ÷ (baseDepositionRate × processEfficiency × environmentFactor × positionFactor) |
| Diameter-adjusted deposition rate | baseDepositionRate × (diameter ÷ referenceDiameter) |
| Setup time (minutes) | round(arcTime × setupPercentage) |
| Total weld time (minutes) | round((arcTime + setupTime) ÷ welderCount) |
| Shielding gas volume (litres) | (arcTime − backGougingTime) × 15 L/min |
| Area per pass | baseAreaPerPass × (selectedWireDiameter ÷ referenceDiameter)² |
| Number of passes | ceil(jointArea ÷ areaPerPass) |
Back-gouging time is excluded from shielding-gas consumption. The selected wire diameter affects pass count; diameter-based arc-time comparisons are supplemental and do not replace the primary estimate.
Environment and Productivity Factors
| Factor | Environment | Setup time |
|---|
| 1.0 | Workshop (Ideal) | 15% of arc time |
| 0.8 | Outdoor (Exposed) | 50% of arc time |
| 0.6 | Restricted Space | 75% of arc time |
| 0.4 | Highly Restricted | 100% of arc time |
Weld Position Factors
| Position | Name | Factor |
|---|
| 1F | Flat (1F/1G) | 1.00 |
| 2F | Horizontal (2F/2G) | 0.88 |
| 3F | Vertical (3F/3G) | 0.70 |
| 4F | Overhead (4F/4G) | 0.60 |
Environment and position factors multiply into the arc-time calculation; a lower factor represents slower production.
Multi-Welder Comparison
| Welders | Individual efficiency | Combined factor |
|---|
| 1 | 100% | 100% |
| 2 | 90% | 180% |
| 3 | 80% | 240% |
| 4 | 70% | 280% |
| 5 | 60% | 300% |
This coordination-efficiency curve is used only in the supplemental multi-welder comparison. The primary total-time estimate divides arc time plus setup time by welder count.
Wire and Electrode Diameters
| Process | Available diameters (mm) | Reference diameter (mm) | Base area per pass (mm²) |
|---|
| GMAW | 1.2, 1.4, 1.6 | 1.2 | 40 |
| FCAW | 1.2, 1.4, 1.6 | 1.2 | 50 |
| SMAW | 2.5, 3.2, 4.0, 5.0 | 3.2 | 30 |
| GTAW | 1.6, 2.4, 3.2 | 2.4 | 18 |
Filler Efficiency and Package Sizes
| Process | Default filler efficiency |
|---|
| GMAW | 92% |
| GTAW | 98% |
| SMAW | 65% |
| FCAW | 88% |
| Process | Package | Weight | Allocation rule |
|---|
| GMAW | 5kg Spool | 5 kg | Minimum one per welder |
| GMAW | 15kg Spool | 15 kg | Minimum one per welder |
| GMAW | 250kg Drum | 250 kg | Shareable |
| GTAW | 5kg Box | 5 kg | Minimum one per welder |
| GTAW | 10kg Box | 10 kg | Minimum one per welder |
| SMAW | 5kg Can | 5 kg | Minimum one per welder |
| SMAW | 20kg Can | 20 kg | Minimum one per welder |
| FCAW | 5kg Spool | 5 kg | Minimum one per welder |
| FCAW | 15kg Spool | 15 kg | Minimum one per welder |
| FCAW | 250kg Drum | 250 kg | Shareable |
Purchase quantity equals deposited weight divided by filler efficiency. Packages below 250 kg require at least one per welder; drums of 250 kg or more can be shared.
Shielding Gas Cylinder Sizes
| Process | Cylinder | Volume (L) | Allocation rule |
|---|
| GMAW | G-Size (50L) | 10,600 | Minimum one per welder |
| GMAW | E-Size (20L) | 4,200 | Minimum one per welder |
| GMAW | D-Size (10L) | 2,100 | Minimum one per welder |
| GTAW | G-Size (50L) | 10,600 | Minimum one per welder |
| GTAW | E-Size (20L) | 4,200 | Minimum one per welder |
| GTAW | D-Size (10L) | 2,100 | Minimum one per welder |
| SMAW | No shielding gas required | — | Not applicable |
| FCAW | G-Size (50L) | 10,600 | Minimum one per welder |
| FCAW | E-Size (20L) | 4,200 | Minimum one per welder |
Gas-shielded processes use a flow rate of 15 L/min during pure arc time. SMAW requires no shielding gas.
Equipment Requirements
| Equipment | Processes | Quantity |
|---|
| Power source | All processes | One per welder |
| Wire feeder | GMAW and FCAW | One per welder |
Per-welder minimum rule: required quantity = max(material-based quantity, welderCount).
Joint Types
| Joint ID | Description | Classification |
|---|
| Butt-V | Butt Joint (Single V-Groove) | Groove |
| Butt-DV | Butt Joint (Double V-Groove) | Groove, Double-sided |
| Butt-Bevel | Butt Joint (Single Bevel) | Groove |
| Butt-DBevel | Butt Joint (Double Bevel) | Groove, Double-sided |
| Tee-Bevel | Tee-Butt (Single Bevel) | Groove |
| Tee-DBevel | Tee-Butt (Double Bevel) | Groove, Double-sided |
| Tee-V | Tee-Butt (Single V-Groove) | Groove |
| Tee-DV | Tee-Butt (Double V-Groove) | Groove, Double-sided |
| Fillet | Fillet Joint | Fillet |
| Lap | Lap Joint | Lap |
Double-sided joints accept separate preparation angles and depths for each side. Their back-gouge area is reduced by 50% because the second side is already prepared.