What do Boilermakers, Pipefitters, and Aerospace welders have in common?
Passing a TIG welding certification test is usually required in order to be considered a qualified welder or to even be hired for the job in the first place.
For boilermakers and pipefitters a pipe or tube welding test is usually required and can be anywhere from 3/8″ to 12 inches in diameter and depending on the job, the material welded is usually carbon steel or stainless steel, or carbon steel welded with ER309 filler metal. (occasionally other alloys are welded but carbon and stainless make up the bulk of welding tests given)
Aerospace welders on the other hand might be required to weld practically any metal:
- carbon steel / low alloy steel – 4130, 4140, 4340, 8630
- stainless steel – 321, 347, 13-8, 15-7, 17-7, a286
- nickel alloys – hastelloy x, inconel 718
- aluminum – A355,356,357 castings, 6061, 2219
- magnesium – az31b,
- titanium – 6AL4V, CP
- cobalt – L605, haynes 188
- refractory alloys like columbium
Aerospace tig welding certifications tests are generally straightforward groove welds or fillet welds unless the special application provision of the American Welding Society D17.1 is used. Sometimes a simple groove or fillet weld test does not accurately represent the scope of welding performed.
In that case there is a provision for the welder to be certified using a scrap part, live part, or mock up test that represents the weld done in production. It is a more limited certification but it helps to certify a welder on tasks that adequately test the skill set required to do the job.
For Boilermakers and pipefitters, a tig welding certification test on tube or pipe pretty much represents the same joint done in the field.
Tips for passing any tig welding test:
- purge…give lots of attention to getting a perfect purge by making sure ends are taped neatly and securely with a vent hole at the top for gas to escape.
- Clean the metal…Whether welding a pipe joint or sheet metal butt weld, if you don’t clean the metal right, you will probably fail. Metals like aluminum and titanium are prone to porosity and filing the edge removes crud that will cause porosity…Some test inspectors will fail you on the spot just for not cleaning the metal.
- For aerospace tig welding tests, make sure to file the sheared edge of the metal
- Degrease with acetone or other approved solvent…give the rod a wipe too.
- Follow instructions…Whether written or from you test supervisor, pay attention, read, and follow instructions.