Work out welding gas consumption instantly with clear inputs, formula shown and shareable results.
Shielding gas use is flow rate times arc time, plus an allowance for pre-flow, post-flow and line purging that is easily 10 percent of the total. Comparing the result with cylinder content shows how many cylinders a job needs, which is often the constraint on site work.
Gas consumed
Litres = flow L/min x arc minutes x (1 + purge allowance)
Cylinders
Cylinders = litres used / cylinder content
Litres = flow L/min x arc minutes x (1 + purge allowance). Shielding gas use is flow rate times arc time, plus an allowance for pre-flow, post-flow and line purging that is easily 10 percent of the total.
Only up to a point. Excessive flow becomes turbulent and draws air into the arc, so porosity often gets worse above roughly 20 L/min on a standard MIG nozzle.
This calculator takes 4 inputs: Shielding gas flow rate, Arc time, Cylinder gas content, Purge and pre-flow allowance. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.