Union S 2 Ni 2,5 is a low-alloy, cryogenic submerged arc (SAW) wire for low-temperature nickel steels. It works on LNG tanks, cryogenic installations and pipework operating below zero.
The wire works as a set with a matched flux, which decides the mechanical properties of the weld, and its copper coated surface improves current pick-up in the contact tip. The deposit keeps its impact toughness in the cryogenic range, so it reaches tanks for liquefied gases.
- Classification EN ISO: 14171-A S2Ni2
- AWS classification: A5.23 / SFA-5.23 ENi2
- Shielding: flux matched to the wire, no shielding gas
- Diameters: 2.4 / 2.5 / 3.0 / 4.0 mm
Run narrow beads without wide weaving, so the weld keeps its fine grained structure. Watch the wire stick-out and the position of the head against the weld centre line, under a flux you cannot see the pool and a mistake shows only after the slag is chipped off. Match the flux to this wire and check how dry it is, drying the flux decides the hydrogen level in the weld.
