Arc and TIG electrodes

[MedicineEng]

Dear All:
I would like to have your oppinion regartding one issue:
Today it happened that I saw one of my guys in the workshop taking out the outer shield of a electrode for arc welding. I got curious and I ask him why. His answer was that he needed to weld TIG and since there were no more TIG electrodes, he removed the outer shield of a arc electrode, with the justification that the core of a electric arc electrode is the same of a TIG electrode. I never heard anything similar, but since the guy is so experienced, I trusted him. But I wanted to confirm with you guys if it is true that the core of the electric arc electrodde is similar or equal to the TIG electrode and what are the risks of such practice.

Thanks a lot

PR

 

[metengr]

PR;
This is a practice that should not be continued. First off, filler metals for arc welding are specially formulated and require the use of the flux coating to meet the intended mechanical property requirements for the weldment. Stripping the flux coating and simply melting the rod into the base metal using the GTAW process will result in a weldment that has unpredictable properties and performance.

 

[GRoberts]

I agree with Metengr. Many stick electrodes have alloying ingredients added to the weld through the coating. Once the coating is gone, you do not know what you weld will end up being (chemistry wise). Tig rod also has deoxidizers that may or may not be in the core wire of a stick electrode to keep porosity away and proven too much free oxygen (and nitrogen), which can cause embrittlement in the weld..

 

[MedicineEng]

Guys:
Thanks a lot for your feedback. I will stop this practice immediatelly.
PR