Gas flow Rate in welding
1.) Gas Flow:-
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The desirable rate of gas flow depends primarily – on weld geometry, speed, current, the type of gas, and the metal transfer mode being utilized.
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Welding flat surfaces requires – higher flow than welding grooved materials, since the gas is dispersed more quickly.
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Faster welding speeds mean – that more gas must be supplied to provide adequate coverage.
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Higher current requires – greater flow, and generally, more helium is required to provide adequate coverage than argon.
2.) Gas Flow Required:-
Metal Transfer Mode |
Gas Flow required |
| Short circuiting & Pulsed spray modes (small weld pools) | 10 L/min (20 ft³/h) |
| Globular transfer | 15 L/min (30 ft³/h) is preferred |
| Spray transfer (higher heat input, larger weld pool) | 20-25 L/min (40–50 ft³/h) |
3.) Plate Thickness V/S Gas Flow Rate:-Â
PLATETHICKNESS |
FOR BUTT JOINT IN FLAT POSITION |
FOR FILLET JOINT IN FLAT POSITION |
                                  GAS FLOW RATE (LPM) |
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| 1.6–2mm | 8–10 | 10 |
| 3mm | 8–10 | 10 |
| 6mm | 12 | 12 |
| 10mm | 12 | 12 |
| 12mm | 14 | 14 |
| 16mm | 14 | 16 |
| 20mm | 16 | 16 |
| 25mm | 16 | 18 |
| 32mm | 18 | 20 |
| 40mm | 18 | 20 |
