Union Al 99,7 is an aluminium solid wire. It welds aluminium and its alloys on aluminium structures, tanks, vehicle parts and shipbuilding products.
It is used on grades such as EN AW-1200, fed continuously from the feeder and welded under shielding gas. The wire works on frames, tanks, housings and light structures, by hand with a semiautomatic torch and on mechanised stations.
- Classification EN ISO: 18273 S Al 1070 (Al99.7)
- AWS classification: A5.10 / SFA-5.10 ER1070
- Shielding gas: I1, I3
Remove the oxide layer with a stainless steel brush right before welding, aluminium oxide melts far higher than the metal itself. Set the gas flow so the pool is covered over the whole length of the bead, and shield the station when you work in wind. Check the contact tip, a worn bore upsets the wire feed and causes burnback. A change of shielding mixture changes the character of the arc, so it is worth a test piece before production.
