OK 68.55

OK 68.55 is a stainless steel MMA stick electrode designed for welding austenitic‑ferritic “Superduplex” steels such as SAF 2507 and Zeron 100.

Key Features

• Basic coating for demanding applications
• Vacuum‑packed (VacPac) to protect from moisture
• Available in multiple diameters and lengths
• High ferrite content (FN 35‑50) for corrosion resistance

Specifications

• Classifications: EN ISO 3581‑A : E 25 9 4 N L B 4 2, SFA/AWS A5.4 : E2594‑15, Werkstoffnummer (1.4410)
• Approvals: DNV‑GL Duplex
• Welding Current: DC+
• Ferrite Content: FN 35‑50
• Alloy Type: Austenitic CrNiMo
• Coating Type: Basic
• Tensile Yield Strength (As Welded): 700 MPa
• Tensile Strength (As Welded): 900 MPa
• Elongation (As Welded): 28 %
• Charpy Impact (As Welded, 20 °C): 90 J; -20 °C: 70 J; -40 °C: 55 J; -60 °C: 45 J
• Typical Weld Metal Analysis (%): C 0.03, Mn 0.9, Si 0.6, Ni 10.4, Cr 25.2, Mo 4.3, N 0.23, FN WRC‑92 45
• Deposition Data:
  • 2.5 × 300 mm → 50‑80 A, 23 V, 62 % efficiency, 0.8 kg/h
  • 3.2 × 350 mm → 60‑100 A, 23 V, 63 % efficiency, 1.1 kg/h
  • 4.0 × 350 mm → 100‑140 A, 23 V, 62 % efficiency, 1.6 kg/h

Applications

• Welding of Superduplex stainless steels
• Projects requiring high corrosion resistance and strength
• Situations where electrode flexibility is essential