13 SEP 12
/ Battery Charging Systems / Welding Technology / Solar Electronics
Weld Process
Gas Flow
• The flow rate of the shielding gas is a critical aspect of 
the welding process.  Too high OR too low will have a 
serious impact on weld results.   
• Rule of thumb for the flow rate: 10 – 12 times the 
diameter in l/min of flow
- 1.2mm x 10 = 12 l/min      
- 1 l/min = 2.1 CFH      
- 12 l/min x 2.1 = 25 CFH
• Helium and Hydrogen require about 50% more flow 
than other gases due to their lighter weights.  
Correct flow rate
Excessive flow rate
Gas Pressure Sensor (4,100,343)
Manually set gas valve that reports a gas error to the weld 
system when flow is too low.  Only errors out for low flow 
and doesn’t report specific flow information.
Digital Gas Sensor (4,100,374)
The specific gas flow is set, regulated, and monitored 
using this device.  Not only is a low or high flow rate 
detected, but the system also reports back specific gas 
flow data.  
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Fronius Options
Typically, the weld system opens and closes the gas 
valve.  If flow monitoring is desired within the system, the 
following options are available.