Thermanit 25/14 E-309L Si is a solid MIG/MAG wire for welding stainless and acid-resistant steels. It works on pressure vessels, process piping and austenitic structures where corrosion resistance counts.
The parent material is S500N. The wire runs under shielding gas, fed continuously from a semiautomatic torch, by hand and on mechanised stations.
- Classification EN ISO: G 23 12 L Si
- AWS classification: ER309LSi
- Diameters: 0.8 / 1.0 / 1.2 mm
Use brushes and discs kept only for stainless steel, carbon steel particles cause rust staining on the face. Match the drive rolls to the wire diameter and check the liner, wire slip shows up at once in an unstable arc. Watch the wire stick-out from the contact tip, too long a one lowers the arc voltage and worsens the fusion. Thinner diameters suit root runs and thin sheet, thicker ones the fill passes.
