Calculate welding travel speed from target heat input or target deposition rate, with support for current, voltage, arc efficiency, weld area and material density.
Travel speed is the speed at which the welding torch, electrode or welding head moves along the joint. It has a direct effect on heat input per unit length.
For a DC welding calculation, electrical power is approximately the product of arc voltage and welding current.
When arc efficiency is included, the approximate effective heat delivered to the workpiece is used to determine heat input per unit length.
Rearranging the equation gives the travel speed:
Use this mode when a welding procedure specifies a target heat-input range or when you want to calculate a travel speed that corresponds to a chosen heat input.
For example, using 25 V, 250 A, 80% arc efficiency and a target heat input of 1.20 kJ/mm:
The result is approximately 250 mm/min, or 15 m/h.
If current and voltage remain unchanged, moving faster reduces heat input per unit length. Moving slower increases heat input per unit length.
Deposition rate describes the amount of weld metal deposited over time. Deposition rate alone does not uniquely determine travel speed because the required deposited weld-metal cross-sectional area must also be known.
The calculator uses the deposited weld-metal area in mm² and material density to determine the mass of weld metal deposited per metre.
For example, with a 3 kg/h deposition rate, a 10 mm² deposited area and steel density of 7.85 g/cm³, the calculated travel speed is approximately 63.7 mm/min.
Travel speed is one of the important variables controlling weld geometry and heat input. It should be considered together with welding current, voltage, electrode or wire size, shielding gas, joint geometry and material thickness.
A travel speed that is too slow can increase heat input and may produce excessive penetration, a wide weld pool or excessive heat-affected-zone effects.
A travel speed that is too fast can reduce heat input and may result in insufficient fusion, inadequate penetration or an undersized weld.
The appropriate speed therefore depends on the qualified welding procedure rather than a universal speed value.
Not all electrical energy supplied to the welding arc becomes useful heat transferred to the workpiece. Arc efficiency accounts approximately for the fraction of electrical energy contributing to effective workpiece heating.
The value varies with welding process and operating conditions.
| Process | Typical Efficiency Range | Important Note |
|---|---|---|
| SMAW / Stick | Approximately 65–80% | Actual efficiency varies with electrode and operating conditions. |
| GMAW / MIG / MAG | Approximately 75–90% | Transfer mode and process conditions affect the value. |
| GTAW / TIG | Approximately 50–70% | Often lower than several wire-fed processes. |
| FCAW | Approximately 70–90% | Varies with wire and shielding arrangement. |
Deposition rate and travel speed are closely related, but they describe different things.
| Unit | Conversion |
|---|---|
| mm/min | Primary unit used by this calculator. |
| m/min | mm/min ÷ 1000. |
| m/h | mm/min × 0.06. |
| in/min | mm/min ÷ 25.4. |
At constant voltage and current, heat input changes inversely with travel speed.
For example, if all other parameters remain unchanged and travel speed is doubled, the calculated heat input per unit length is approximately halved.
This relationship is useful when establishing welding parameters within a specified heat-input range.
This calculator provides an engineering estimate. It does not determine the complete welding procedure.
A calculated travel speed should be checked against the allowable current range, voltage range, deposition rate, joint geometry, material thickness and qualified welding procedure.
How do I calculate welding travel speed from heat input? Use voltage, current, arc efficiency and target heat input. Travel speed is V × A × 60 × efficiency divided by 1000 × target heat input.
What happens if I increase welding travel speed? At the same current and voltage, increasing travel speed reduces heat input per unit length.
What happens if I slow down the welding travel speed? Slower travel increases the heat input delivered per unit length when current and voltage remain unchanged.
Can deposition rate determine travel speed? Yes, provided the deposited weld-metal cross-sectional area and material density are known.
Why is weld cross-sectional area needed for deposition calculations? A deposition rate tells you how much metal is deposited per unit time, while travel speed tells you how much joint length is covered per unit time. Weld area connects the deposited mass to the length.
What is a good welding travel speed? There is no universal value. The appropriate speed depends on the process, current, voltage, material, joint, electrode or wire and required weld characteristics.
Does arc efficiency affect calculated travel speed? Yes. A higher assumed arc efficiency means more of the electrical energy is treated as effective workpiece heat, changing the travel speed corresponding to a target heat input.
Is travel speed the same as wire feed speed? No. Wire feed speed is the rate at which filler wire enters the arc, while travel speed is the movement of the torch or welding head along the joint.
Can this calculator be used for TIG? Yes. The heat-input calculation can be used as an estimate for TIG when an appropriate arc-efficiency value is selected.
Can this calculator determine a complete welding procedure? No. It calculates travel speed from selected target parameters. Welding procedures require additional variables and qualification where applicable.