Download Tech Paper PDF : See 7 Customers With Start Quality Improvements
The first 15 years of my career were in welding R&D with the leading Industrial Gas/Welding company at the time (Linde renamed Praxair, now German Linde.) While managing the company’s filler metals and shielding gases R&D Lab, we understood the shielding gas surge at a weld start was excessive, caused turbulent flow and inferior weld starts. But, we never took the time to quantify the extent of the problem or methods to improve. Since forming WA Technology in 2000, from fabricator visits and our research, we have found the starting gas surge not only causes inferior weld start quality it is also a major cause of shielding gas waste
Fabricator Testimonial.
When testing our patented Gas Saver System (GSS) at American SpiralWeld Pipe with the objective of reducing costs, the welding engineer and I were surprised when the welder immediately said he could see the difference! Not the gas savings but the improved weld starts. The tests showed a 40+% gas savings but more important to the welder, the improved weld starts! When his repair welds were completed they required Ultrasonic Testing before the repaired part could continue in production. They were finding a significant amount of subsurface weld start porosity. They used flux cored wire and CO2 shielding for the repair welds. The welder said he knew the starting gas surge was the cause. He would cut the wire back to the tip and hold the torch well above the work when he triggered the MIG gun to minimize the peak surge effect.
(Our LAB tests showed that was no help as the turbulent surge was a 3+ second problem!) With the GSS he immediately saw the gas surge was significantly reduced!
The following is a graph showing the starting flow test data from the welding station making repair welds with and without the GSS.
With a standard gas delivery system, the surge flow rate is very turbulent and mixes air into the shielding gas stream causing excess spatter and internal porosity. Note with their standard gas delivery system the flow exceeded 100 CFH for 2 ½ seconds. With the GSS peak flow was under 100 CFH and quickly returned to the preset 35 CFH. After using the GSS for 6 months, the welder said he had very few rejects compared to previously a common occurrence!
With a standard gas delivery system, the surge flow rate is very turbulent and mixes air into the shielding gas stream causing excess spatter and internal porosity. Note with their standard gas delivery system the flow exceeded 100 CFH for 2 ½ seconds. With the GSS peak flow was under 100 CFH and quickly returned to the preset 35 CFH. After using the GSS for 6 months, the welder said he had very few rejects compared to previously a common occurrence!
2nd Testimonial (Large Fabricator) :
Recently discussed weld quality with the Maintenance Manager of one of our largest customers, Chart Industries at a plant in Louisiana. He has worked there for over 20 years and had an interesting perspective on all the benefits of our GSS .
They manufacture liquid natural gas production equipment and storage tanks. Their welds are all nondestructive tested. We discussed shielding gas savings as they have well over 500 GSS systems. I mentioned some folks have difficulty understanding how we save gas. His comment was: “It’s so obvious when you look at the small ID versus the typical hose.” Then I remembered they deal with pressurized gases and understood the excess pressure in the gas delivery hose at each weld start causes the gas blast, high initial flow rate and waste.
He said additionally a major cost benefit is the reduced weld start defects and they observed using our GSS.
This facility also found that our heavy wall GSS hose, with its unique construction, significantly reduced hose moisture permeation, eliminating hydrogen weld defects.
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