History of TIG (GTAW) Welding

Invention and Development

Meredith Invents TIG:

Like MIG welding, there are a number of references sighting "inventors” of TIG  welding.  However Russell Meredith, working for Northrop Aircraft, was the first to produce a system that was a true production tool applying for a patent in January 1941 (US Patent # 2,274,631, Figure 1 left.)  He was concerned about meeting a critical national need of welding light weight aircraft materials.  In the first line of the patent it states; “My invention relates to welding magnesium and its alloys - - so relatively low melting point materials may be efficiently welded by an electric arc.”  He goes on to say that airplanes are being made of lighter materials and a more efficient method of joining these materials is needed.

Although Meredith's work was done with Helium shielding gas and a tungsten electrode his 4 patent claims are very broad only mentioning an "inert gas" and “refractory” welding electrode.  Validating that this was the first workable system and Meredith was the inventor of TIG; there is no prior art sited against his patent by himself or the US Patent Office.

Similar to the 1st MIG Welding Patent emphasizing the need for Laminar shielding gas flow,  Meredith states that the shape of the end of his TIG torch is designed to prevent oxygen (referring to air intrusion) from being drawn into the arc by the Helium outflow.  From a review of other devices shown in prior patents it is obvious the inventors did not understand the importance of shielding quality and what was required to produce Laminar flow.  Note: I encourage reviewing these patents, which is a reason the numbers are provided.  There is a great deal of useful information available - and they are Free! (Unfortunately some of today's welding professionals  do not understand that excess gas flow  creates  turbulence that pulls air into the shielding stream. Depending the nozzle size, the flow rate causing turbulence is only somewhat higher than that used when welding! ) 

Linde Buys Patents and Heliarc Name:

Meredith and Northrop Aircraft called the welding process Heliarc^R and sold the patent and trademark rights to the Linde Division of UCC.  Linde, unlike Northrop,  had the incentive to spend the needed funds and manpower to develop the process since  their business was manufacturing and marketing inert (and other industrial) gases.  They developed a whole series of Heliarc brand torches.  Frank Pilia who worked in the Linde Labs invented and patented a water cooled TIG torch (# 2,468,806  filed May, 1946;  figure left.)  Pete Scheller also worked for Linde and filed a patent in May 1951, # 2,685,631, for a torch where the head could be bent as needed for access to difficult to reach areas such as pipe welding (figure lower right.)

In addition to numerous torch patents, Linde developed systems to improve shielding and allow the tungsten electrode to protrude further from the gas cup for better visibility while still providing the needed excellent shielding.  Another colleague, Gene Gorman,  invented the first “gas lens” as it was referred to in his patent filed April 1960, US 3,053,968.   Item # 56 (upper left figure) shown in patent figure  upper left is referred to as a “baffle” with a varying number of holes.  As Gorman notes in the patent teaching, very small holes produced a longer coherent gas stream substantially without Turbulence.  One material mentioned was a 200 mesh screen. This produced much better shielding than the porous bronze type materials he evaluated.  When Gorman tested porous bronze materials he found the gas leaving this type of materials exited in various directions creating a more Turbulent gas stream! 

[Some companies are trying to sell porous material designs for a gas lens-it is no doubt much easier to make!  Wonder if they ran the Schlieren gas flow tests and made sufficient welds in various materials to validate its effectiveness, as did Gorman?  See Gas Lens Tests Below.  I shared an office with Gene when I started at the Linde Labs.  Gene was developing a three electrode TIG system for high speed welding of stainless steel in tube mills.  I was developing a three wire Submerged Arc System that welded large diameter UOE steel pipe for oil and natural gas transmission, which welded with 3000 amps!]

Gorman shows the resulting gas outflow in one of the patent figures (above left) and quantifies his finding in a graph.  The graph (above right) shows an improvement in the length of the coherent gas stream of 6 fold with a device he called a gas lens. 

Another Linde engineer, Cliff Hill, defined an improved method of making a gas lens in his patent filed in 1961, # 3,180,967.  Cliff’s design (patent figure left) used multiple fine size screens stacked to provide the Laminar flow needed and as defined in the Gorman patent.  He found these very fine screens could be combined with a coarser, more ridged screen on the outside to improve the durability of the assembly.  This construction did not alter the ability to produce the desired long coherent gas stream.  This design is still used today to produce the best quality shielding gas lens..

Cliff Hill was a very dedicated engineer with many patents in the TIG torch area.  He was a very creative person and a man of few words. I recall a comment made by Cliff after a lengthy meeting we were having with engineering.  He said, "perhaps we should remove all the chairs in this conference room and the meetings won't last as long!"

Gas Lens Test

Engineers at ESAB recently tested several TIG gas lens designs after reviewing problems encountered by a major shipyard.   One type was a single piece made of a porous material and the other had multiple screens similar the genuine Heliarc design that ESAB markets but with fewer and coarser screens.

The most definitive test results were observed after carefully making welds with AC power in aluminum and noting the quality of the cleaning action.  The amount and consistency of cleaning with the porous, single piece material and the one with coarse screens was not much better than welds made with a standard non-gas lens collet.  The genuine Heliarc Gas lens with fine internal screens and a coarser cover screen, as originally patented by Hill (see above,) gave excellent uniform cleaning, much better than the other two types.

Gorman in his tests in the early 1960's reported in his initial patent (see above) explaining why he found porous materials did not work - the gas exits in various directions.  He discovered stacked fine screens provided the  desired long, laminar gas stream.

Pressed porous materials and the use of fewer, lower cost, coarse screens are no-doubt much easier to produce and lower in cost than the properly assembled, more expensive fine screen design.  However the weld results showed this was false economy!

Side Bar

Of interest, 50 foot long  (and sometimes longer) cable systems are sold for TIG Torches.  The gas hose used for these long cable systems has a small inside diameter (ID.)  It is the same size ID as our much heavier wall thickness, custom extruded, hose utilized for our Gas Saver System (GSS ^TM.)  Some folks question if our GSS can flow a sufficient quantity of gas - the answer is easily!  The reason is MIG and TIG gas flows are quite low compared to the flow rate of oxygen, for example, in oxyacetylene welding and cutting.  Also, many companies copy the original Heliarc Torches, Collets, Collet Bodies and Hose Assemblies and even use the original part numbers.  They also continue to copy the somewhat unusual 12 ½ foot length of the shorter length torches.  I wonder how many of these copiers know why this unusual 12 ½ foot length was selected?  Having worked with the developers of Heliarc TIG products - I do!  It is a similar intriguing reason as why most TIG and MIG gas delivery hoses from gas supply to power source (or wire feeder)  are a shielding gas "wasteful" 1/4 inch ID!  Email TechSupport@NetWelding.com if you'd  like to know! 

See how our patented "Gas Saver System" can benefit TIG welding.

The gas lens allows the tungsten to be placed well outside the gas cup to increase visibility (the actual gas flow with and without a gas lens is shown left).

TIG Hot Wire

The TIG welding process saw a major advancement when an engineer at the Linde Labs invented TIG “Hot Wire.”  Gus Manz filed patent, 3,122,629 in February 1962.  It provided TIG quality with MIG deposition rates.  It was mostly (and still is) used for automatic installations.

Instead of slowing adding cold wire to the TIG weld puddle, the “Hot Wire” is heated just below the melting point and reacts just like squirting toothpaste into the puddle!  The wire exits the contact tip cold (T in the above schematic) and is heated by a power source (H) as it passes from the tip to the weld puddle with just enough power to make it "mushy" as it enters!  MIG metal deposition rates are achievable.  A subtle but important advantage is the heated wire burns off all volatile wire surface residuals before it enters the puddle making it an extremely low hydrogen process.

Another colleague, Fritz Saenger, in patent 3,588,464 filed in April 1969, defined a potentially very useful product, a manual TIG hot wire torch.  This torch design made it easy for a welder to add the “Hot Wire.”  It takes this integrated approach to achieve a system that will work in production better than simple add-on approaches.

Other TIG Innovations:

There were other innovations such as very high frequency power that constricts the arc and multi-electrode systems that increased speeds in production such as welding on stainless tube mills.  Flexible and silicon covered TIG torches were also introduced.  Today’s microprocessor controlled inverter power systems also make TIG welding easier to use and more controllable. 

Note: Heliarc is a registered trademark of ESAB Welding & Cutting

See History of Other Welding Processes:

MIG (GMAW)

Sub Arc

Electroslag

Friction Stir Welding

Excessive heat is a common complaint of welders.  This helmet helps solve the excess heat problem by providing cooled, clean, breathable air. Note patent covers a number of configurations including typical welding PAPR construction and possible use of a backpack arrangement. With the new very low allowed manganese fume levels (4 times lower than Phosgene, the WW I poison Gas!) this patented helmet design is even more important! Welders will like wearing it versus a conventional PAPR or quality respirator since it also helps their hot working environment! CLICK To See Web Page Discussing Fume Details.

We are searching for a company to license these designs, including  large fabricators  employing a number of welders who would benefit from the reduced heat and better environment. Contact Jerry_Uttrachi@NetWelding.com if interested.

Of interest some NASCAR teams are currently using a thermoelectric device to cool hot drivers! Their light weight compact device does not even use our patented idea that reduces power requirements by 50% or more.

Have a MIG Welder?  

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Note: Our Patented GSS is Not Available in "Stores"

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A home shop fabricator in Georgia with a Miller ^TM 175 amp welder purchased a 50 foot Gas Saver System ( GSS ^TM ) so he could use a larger cylinder and mount it on the wall of his shop.  He wrote:

"The system works great.  Thanks for the professional service and a great product."   Click To See His Home Shop

A Professional Street Rod Builder Had This to Say:

With their standard MIG welder gas delivery hose the peak shielding flow at weld start was measured at 150 CFH. That caused air to be sucked into the gas stream causing poor weld starts.  With the  replacing their existing hose, the peak flow surge at the weld start was about 50 CFH.  Total gas use was cut in half.

Kyle Bond, President, quickly saw the improvement achieved in weld start quality as a significant advantage!   Kyle, an excellent automotive painter, was well aware of the effects of gas surge caused by pressure buildup in the delivery hose when stopped.  He has to deal with the visible effects in the air hose lines on the spray gun in his paint booth!  The paint surge is visible and creates defects unless the gun is triggered off the part being painted!  We can’t do that with our MIG gun!

GAS SAVER SYSTEM (GSS ^TM) PURCHASE INFORMATION

GSS Customer Testimonial: PDF Download

See YouTube Videos

Including Our Patented MIG Shielding

"Gas Saver System" (GSS)

Science of MIG Shielding Gas Flow Control

Why MIG Gas Waste

Detailed Review of GSS

Short Overview of GSS-90 Seconds

What User Say About GSS

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