OK 67.50

OK 67.50 is an acid‑rutile coated stick electrode designed for welding austenitic‑ferritic duplex stainless steels (CrNiMoN 22‑5‑3 and CrNiN 23‑4). It delivers high strength, good ductility, and excellent pitting corrosion resistance while being resistant to stress corrosion cracking.

Key Features

• Acid rutile coating for easy arc starting and stable weld pool
• Duplex CrNiMoN alloy for high strength and good ductility
• Wide welding current range (DC+, AC) with good deposition efficiency
• VacPac hermetically sealed packaging to prevent moisture absorption

Specifications

• Coating Type: Acid Rutile
• Alloy Type: Duplex CrNiMoN
• Welding Current: DC+, AC
• Ferrite Content: FN 35‑50
• Minimum AC Open Circuit Voltage: 60 V
• Yield Strength (As Welded, ISO): 691 MPa
• Tensile Strength (As Welded, ISO): 857 MPa
• Elongation (As Welded, ISO): 25 %
• Charpy Impact (20 °C, As Welded, ISO): 50 J
• Charpy Impact (‑30 °C, As Welded, ISO): 41 J
• Typical Weld Metal Composition (wt %): C 0.03, Mn 0.8, Si 0.8, Ni 8.8, Cr 23.2, Mo 3.2, N 0.16, FN 42
• Deposition Data (example 4.0 mm × 350 mm): 90‑160 A, 29 V, 58 % efficiency, 59 s/fusion, 1.9 kg/h

Applications

• Welding of duplex stainless steel structures
• Offshore and chemical plant fabrication
• High‑corrosion‑resistant weldments
• Situations requiring flexibility of SMAW process