Successful Gas Tungsten Arc Welding

Tungsten is a rare metallic element used for manufacturing gas tungsten arc welding (GTAW) electrodes. Tungsten electrodes are available in a range of sizes and lengths and are made up of either pure tungsten or an alloy of tungsten and other rare-earth elements and oxides. Choosing an electrode depends on the base material type and thickness and whether you weld with alternating current (AC) or direct current (DC). Each electrode is color-coded at the tip to eliminate confusion over its type. Unlike the red-tipped thoriated tungsten electrode that contains two percent thoria, blue-tipped MultiStrike® tungsten electrodes from Huntingdon Fusion Techniques HFT® are available in the U.S. from COB Industries Inc. (Melbourne, FL) and contain a mix of non-radioactive rare earth elements, eliminating the risk to health posed by thoriated tungsten electrodes.

“We have tested these electrodes under production conditions where we need to make short lengths welds using the TIG process,” said one customer. “On a batch of 50 components, only two light regrinds were required compared to seven heavy regrinds when using thoriated electrodes. Even when the welder occasionally touched the work with the electrode, there was no material change in performance that we would normally expect to have to regrind. Better weld quality and finish was observed. We were particularly impressed with the health and safety aspects, and have decided to remove all thoriated electrodes from our site.” MultiStrikes can be used for welding aluminum with the AC process, as well as steels and alloys with the DC process, which allows the welder to have just one type of tungsten electrode to weld all materials and reduce the amount of stocks and purchasing requisitions.

Other tungsten electrodes work at higher temperatures so their oxide additions (mostly radioactive) burn out, or evaporate much faster than those non-radioactive ingredients in MultiStrike, so much so that they give at least ten times more arc striking capacity of other tungsten electrodes, when tested under the same conditions. With most tungsten electrodes in use still containing radioactive and carcinogenic two percent thorium oxide, MultiStrike provides the TIG and plasma welder with a safe and superior alternative. Each packet comes with a traceability number to ensure that shops with a quality control procedure have traceability over another aspect of their joining processes.

COB Industries Inc., 6909 Vickie Circle, Melbourne, FL 32904, 321-723-3200, [email protected], www.cob-industries.com.