The Following is a Summary of the Article in the 
    AWS Journal
    
    "GMAW 
    SHIELDING GAS FLOW CONTROL SYSTEMS"
    
    An article was published in the American 
    Welding Society's (AWS) April Welding Journal (page 22) with the above 
    title.
    
    It defined what
    
     "Automatic 
    Gas Flow Control was all about.  As stated, the pressure upstream of 
    the flow control must be a minimum of 25 psi to have this feature.  
    That is why MIG welding gas supply systems have been set at this pressure or 
    higher from the inception of MIG welding.  Recently some "low pressure" 
    devices have been introduced in attempt to solve shielding gas waste due to 
    starting surge.  These systems do not maintain flow.  As stated in 
    the article variations in flow of up to 65% were measured with such systems.  
    It also suggests ways are available to retain "Automatic Flow Control" while 
    reducing shielding gas waste.
"Automatic 
    Gas Flow Control was all about.  As stated, the pressure upstream of 
    the flow control must be a minimum of 25 psi to have this feature.  
    That is why MIG welding gas supply systems have been set at this pressure or 
    higher from the inception of MIG welding.  Recently some "low pressure" 
    devices have been introduced in attempt to solve shielding gas waste due to 
    starting surge.  These systems do not maintain flow.  As stated in 
    the article variations in flow of up to 65% were measured with such systems.  
    It also suggests ways are available to retain "Automatic Flow Control" while 
    reducing shielding gas waste.
    
    Click on the photo above for a Link to 
    the AWS article.
    
    
    CLICK HERE 
    to see the actual flow test results of standard systems compared to a 
    commercially sold "low pressure system that mounts at the feeder.