# Shielding Gas Consumption and Cost Calculator > Source: https://netray.co/tools/shielding-gas-consumption-cost-calculator > Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems. > Section: Free Tools ## Short answer Estimate monthly shielding gas use, cost and cylinders from flow rate, arc-on time and purge time per weld. ## Category industry-templates ## Industry Welding & Fabrication ## Audience - Welding supervisor - Purchasing - Fabrication shop owner ## Tool **Kind:** calculator **Inputs:** #### Gas flow rate **Key:** flow **Type:** slider **Default:** 15 **Min:** 5 **Max:** 30 **Step:** 1 **Unit:** L/min #### Arc-on hours per month **Key:** arc_hours **Type:** number **Default:** 80 **Min:** 0 **Step:** 5 **Unit:** h #### Number of weld starts per month **Key:** welds **Type:** number **Default:** 3000 **Min:** 0 **Step:** 100 #### Pre-flow plus post-flow per weld **Key:** purge_s **Type:** number **Default:** 4 **Min:** 0 **Step:** 0.5 **Unit:** s #### Gas price **Key:** price **Type:** number **Default:** 12 **Min:** 0 **Step:** 0.5 **Unit:** per m3 #### Gas per cylinder **Key:** cyl **Type:** number **Default:** 10 **Min:** 0.1 **Step:** 0.5 **Unit:** m3 **Help:** A common 50 litre cylinder at 200 bar holds roughly 10 m3. #### Allowance for leaks and over-flow **Key:** leak **Type:** slider **Default:** 10 **Min:** 0 **Max:** 40 **Step:** 1 **Unit:** % **Outputs:** #### Gas used while welding **Key:** arc_m3 **Expr:** flow * 60 * arc_hours / 1000 **Format:** decimal **Description:** m3 per month. #### Gas used in pre/post flow **Key:** purge_m3 **Expr:** flow * purge_s * welds / 60 / 1000 **Format:** decimal **Description:** m3 per month. #### Total gas per month **Key:** total_m3 **Expr:** (arc_m3 + purge_m3) * (1 + leak / 100) **Format:** decimal **Primary:** true #### Gas cost per month **Key:** cost **Expr:** total_m3 * price **Format:** currency **Primary:** true #### Cylinders per month **Key:** cyls **Expr:** ceil(total_m3 / cyl) **Format:** integer #### Share spent on pre/post flow **Key:** purge_share **Expr:** if(gt(arc_m3 + purge_m3, 0), purge_m3 / (arc_m3 + purge_m3) * 100, 0) **Format:** percent **Description:** High values point to very short welds or long flow timers. **Chart:** #### Monthly gas cost vs flow rate **Type:** line **X:** flow **From:** 5 **To:** 30 **Steps:** 26 **Series:** - cost **Disclaimer:** Cylinder content depends on size, pressure and gas type. Use your supplier's delivered cubic metres per cylinder. ## Content **Intro:** Shielding gas is a quiet cost line: often bigger than people think and easy to cut. This calculator estimates monthly volume, cost and cylinder count from flow rate, arc time and the gas wasted in pre-flow and post-flow around every weld. **Sections:** #### How to use it **Body:** Enter the flow rate you actually set at the regulator, the arc-on hours per month from your production data, and the number of weld starts. Add the pre-flow and post-flow time per start and your delivered gas price. Add a leak allowance if hoses, fittings or torches are not regularly checked. The result gives gas used, monthly cost, cylinders to order and how much is lost in purge time rather than welding. #### The arithmetic **Body:** Gas while welding is flow in L/min times 60 times arc hours divided by 1000, in cubic metres. Purge gas is flow times purge seconds times weld starts, divided by 60 and 1000. The sum is increased by the allowance percentage. Multiply by price for cost, and divide by cylinder content to get cylinders. The numbers are simple on purpose so you can check them against your invoices. #### Where the savings are **Body:** Flow is the lever with the largest effect. Many shops run 18 to 20 L/min out of habit when 12 to 15 holds quality in still air. Drafts do the opposite, so fix drafts before raising flow. Short tack welds with long post-flow timers can burn a large share of the gas, which the purge share output shows. Check hoses and quick connectors for leaks, which are a common hidden loss. **Bullets:** - Verify flow at the torch with a flow meter - Shorten post-flow only as far as the weld stays bright - Use the supplier's delivered price per m3 #### Common mistakes **Body:** Confusing the flow meter reading with real flow at the nozzle is common, especially with long hoses and gas savers. Another mistake is quoting cylinders by their water volume rather than delivered cubic metres. Finally, do not cut flow without a trial: porosity rework costs far more than the gas saved. **Cta:** If gas usage per job is not tracked, Netray can help add consumption capture and variance reporting to your existing ERP or MES data. **Faq:** #### How long does a welding gas cylinder last? **Answer:** Divide the delivered gas in the cylinder by the flow rate. A 10 m3 cylinder at 15 L/min lasts about 11 hours of continuous flow, which is more than 11 hours of welding because the gas also runs during purge and idle. #### What flow rate should I use for MIG? **Answer:** A common starting range is 12 to 18 L/min in still air, depending on nozzle size, gas type and joint. Windy conditions or large nozzles need more, but excessive flow causes turbulence and can draw air in. #### Does pre-flow and post-flow matter that much? **Answer:** For long welds, no. For production with thousands of short welds, it can account for a significant share of gas. The purge share output shows whether your timers are worth tuning. #### Is argon or CO2 cheaper per hour? **Answer:** CO2 costs less per cubic metre but may lower travel speed and raise spatter. Compare cost per metre of finished weld, not cost per cubic metre of gas. ## Search terms shielding gas consumption calculator, argon gas consumption welding, mig gas flow rate cost, co2 gas consumption welding, how long does a gas cylinder last welding, gas cost per hour welding, pre flow post flow gas waste, welding gas cylinder calculator --- Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json