INE E8018-B2 H4 – Low Hydrogen Cr-Mo Alloy Steel Electrode (3.2mm) Product Overview The INE E8018-B2 H4 3.2MM is a premium low-hydrogen, iron powder coated electrode engineered for welding chromium-molybdenum (Cr-Mo) alloy steels used in high-temperature, high-pressure service applications. Classified under AWS A5.5 / ASME SFA-5.5 as E8018-B2, this electrode delivers a weld deposit with a nominal composition of 1.25% Chromium and 0.5% Molybdenum, making it ideal for petrochemical, power generation, and refinery piping systems that operate under elevated temperatures. The "H4" designation indicates a controlled diffusible hydrogen level of 4 mL/100g of deposited weld metal or less, ensuring superior resistance to hydrogen-induced cracking (HIC) — a critical requirement for thick-section and crack-sensitive alloy steel welding. Key Specifications Attribute Detail AWS Classification E8018-B2 Hydrogen Level H4 (=4 mL/100g) Diameter 3.2mm (1/8") Coating Type Low Hydrogen, Iron Powder Current Type AC / DC+ (Reverse Polarity) Alloy Content 1.25% Cr, 0.5% Mo Tensile Strength = 80,000 psi (552 MPa) Application Cr-Mo steel, high-temp/high-pressure piping Key Features & Benefits Low Hydrogen H4 Rated – Minimizes risk of underbead and hydrogen-assisted cracking, ideal for thick, restrained, or high-carbon-equivalent joints. Excellent Creep Resistance – The 1.25Cr-0.5Mo deposit maintains strength and structural integrity at elevated service temperatures (commonly up to 550°C / 1000°F). Smooth, Stable Arc Characteristics – Iron powder coating improves deposition rate, arc stability, and reduces spatter for a cleaner weld bead. Excellent Weld Bead Appearance – Produces a smooth, uniform bead with easy slag removal and minimal post-weld cleanup. X-ray Quality Welds – Suitable for critical, code-required applications demanding radiographic-quality soundness. Versatile Positional Welding – Typically suited for flat and horizontal position welding (verify manufacturer datasheet for full positional capability). Common Applications Power plant boiler tubes, headers, and steam piping Petrochemical and refinery process piping Pressure vessels operating at elevated temperatures Cr-Mo alloy steel pipe and fitting fabrication Oil & gas high-temperature service equipment Recommended Welding Parameters (3.2mm) Typical amperage range: 90–140 Amps (verify against manufacturer's technical data sheet for exact settings, polarity, and preheat/interpass temperature recommendations, as these vary based on base metal thickness and joint design). Handling & Storage Recommendation As a low-hydrogen electrode, proper storage is essential to maintain the H4 rating. Store in a holding oven at 100–150°C (212–300°F) after opening, and re-bake per manufacturer guidelines (typically 350–400°C) if exposure to ambient humidity exceeds the recommended limit.
