A Trailer Body Builders magazine article quotes a representative from a leading producer and marketer of shielding gases, Praxair, indicating their market survey findings show the average fabricator using MIG welding consumes 6 times the amount of shielding gas theoretically needed.  Stated as a percentage, 83% of the shielding gas used is wasted! (Reference 1 Below)

Another article in The Fabricator magazine confirmed this finding of up to 6 times the needed shielding gas  being used in fabrication shops. This article discuses and quantifies a major reason for gas waste being the high gas flow surge at the weld start. (Reference 2 Below)

First Reason for Gas Waste: GAS SURGE

The surge of excess shielding gas occurring at every weld start is a major contributor to the gas waste.  (Note: by disconnecting the wire feed and depressing the torch trigger the high velocity gas surge can easily be heard exiting the torch nozzle.)  Each time the torch switch is pulled, up to 6 times the physical gas hose volume (from gas supply to the wire feeder or welder) is wasted.  In addition to the gas waste this gas surge creates a turbulent  shield that pulls air into the weld zone.  This moisture laden air causes inferior quality weld starts with internal weld porosity and excess weld  start spatter.

THE SOLUTION: The use of our recently patented Gas Saver System (GSS ^TM )  reduces this excess gas surge by 80%. One fabricator purchased our GSS and tested the amount of gas waste reduction. Their tests were made using shielding gas from cylinders for accurate measurement. With the normal gas hose and welding machine settings they welded 236 identical parts with a full cylinder.  They installed our GSS replacing their gas delivery hose and with no other changes they welded 632 of the same parts with a full cylinder!  All gas savings were from the reduced gas surge at the weld start.  See Why the Gas Surge Exists and How the GSS  Works.

Have Questions about our Gas Saver System.  Click for some Q&A that may help or

Second Reason for Gas Waste: EXCESS FLOW SETTINGS

We have often found gas flowmeters with the ball pinned to the top of the flow tube.  Our tests show this can be a 150 Cubic Feet per Hour (CFH) gas flow rate.

This excess is not only wasteful but causes poor weld quality.  The following is a quote from a recent article published in Practical Welding Today by Kevin Lyttle, Manager Welding R&D for Praxair which states;  “In many instances production site surveys (of fabricators using MIG and Cored Wire) determine that shielding gas flow rates typically are set in excess of 50 CFH.  This can contribute to poor weld quality as atmospheric gases are drawn into the arc zone because of excess gas turbulence.  Optimized flow enhances quality and reduces shielding gas usage.” (Reference 3 Below)

Another article by The Welding Institute in Cambridge England qualified the maximum flow rates in a MIG torch before excess turbulence was created.  For the most common 5/8 inch ID MIG torch nozzle, 48 CFH is the maximum flow rate before turbulence is encountered.  For those using low current MIG welders employing the typical ½ inch ID MIG torch nozzle (used by most small shops and home users) will allow only a 37 CFH maximum flow before encountering turbulence. (Reference 4 Below)

Research performed to see if increased flow could improve weld quality in a 5 MPH wind environment yielded interesting results.  This unpublished work showed that with a standard 5/8 inch ID MIG torch nozzle, a 45 CFH shielding gas flow rate produced less internal porosity than 65 CFH!  This validates that turbulence created by the 65 CFH flow rate causes moisture laden air to be sucked into the shielding gas stream and is counter productive.  Unfortunately many welders and other folks involved in welding think "if some shielding gas is good more must be better."

We find a number of  people generally knowledgeable about welding:

1. Don't understand the excess gas flow problem;

2. Don't understand that the high start gas surge is a key  reason for shielding gas waste and weld problems or if they do;

3. Don't communicate the problem to welders;

4. Believe reducing system gas pressure helps, not understanding that this approach creates more problems by eliminating Automatic Flow Compensation built into MIG gas delivery systems since the process was invented! 

When discussing our GSS with an engineer at a plant making highway trailers he said his gas supplier just checked their flow rates and the 100 CFH set by flow control orifices at their pipeline gas drops was fine! 

Their gas supplier should have read the article published by the Manager of Welding R&D for the largest Shielding Gas Producer, Praxair!  CLICK to see why he says in excess of 50 CFH GAS FLOW  causes weld quality problems!

THE SOLUTION: If  you’re using flowmeters on cylinders or on a pipeline gas supply a patented lock (photo right) is available that allows the maximum flow rate to be set and locked.  See Details.

Third Reason for Gas Waste: LEAKS.  We have found leaks are often subjectively viewed as the cause of all gas waste.  That is an easy excuse for a gas supplier to make when purchasing finds gas use is far more than calculations show should be used (Click to See A Way to Determine How Much Gas You Should Use.)  We have also found leaks are frequently not as significant a cause of waste as initial gas surge and excess flow settings.  However leaks are easy to detect and fix and should not be tolerated.  Another reason to fix leaks is their effect on weld quality.  When gas is leaking out of a pipeline, hose or fitting; moisture laden air is leaking back through the passage that caused the leak! 

THE SOLUTION:  Click to see our home study training programs that define  problems related to leaks and how to correct them.  It also identifies ways to have lead welders, welding foreman etc, measure and plot gas versus wire use that will help detect leaks.  Also discussed is the reason moisture and air  flow back through a hole where gas is leaking out!

REFERENCES:

1. Weber, R., How to Save 20% on Welding Costs. Trailer/Body Builders, Volume 44, Number 3, January 2003
2. Standifer, L. R., Shielding Gas Consumption Efficiency. The Fabricator, Volume 30, Number 6, June 2000.
3. Lyttle, K. and Stapon, G., Simplifying Shielding Gas Selection. Practical Welding Today, Vol. 9, No. 1, Jan/Feb 2005.
4. Wilkinson, M. E., Direct Gas Shield Analysis to Determine Shielding Efficiency. Report of The Welding Institute, Cambridge, England, December 1974

Free Technical Paper, "MIG SHIELDING GAS CONTROL"

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