Hastelloy B-2 (ERNiMo-7) Welding Wire Guide

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What is Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

Hastelloy B-2 (AWS ERNiMo-7) is a nickel-molybdenum welding wire for welding Hastelloy B-2 and B-3 alloys. Provides excellent resistance to hydrochloric acid at all concentrations and temperatures. Low carbon and iron content minimizes carbide precipitation.

What welding parameters are recommended for Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

Parameter	GTAW	GMAW
Shielding Gas	Argon (99.995%)	Ar + 2% He or Ar + 2% CO2
Gas Flow Rate	8-15 L/min	15-25 L/min
Wire Diameter	1.6-3.2 mm	0.8-1.6 mm
Current Type	DCEN	DCEP
Welding Position	All positions	Flat / Horizontal

Where is Hastelloy B-2 (ERNiMo-7) Welding Wire Guide used?

Hastelloy B-2 welding wire is used in a wide range of demanding applications:

• HCl Service: Welding of equipment handling hydrochloric acid.
• Chemical Processing: Welding of B-2/B-3 process equipment and piping.
• Reducing Environments: Welding for environments with reducing acids.
• Vacuum Furnaces: Welding of vacuum furnace components.
• Pharmaceutical: Welding of high-purity process equipment.

Which product forms are available for Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

Hangbo Alloy Group supplies Hastelloy B-2 welding wire in the following forms:

• TIG Wire: Straight lengths 1000 mm, diameters 1.6 mm, 2.0 mm, 2.4 mm, 3.2 mm.
• MIG Wire: Precision-wound spools (D200, D300), diameters 0.8 mm, 1.0 mm, 1.2 mm, 1.6 mm.
• SAW Wire: Coils for submerged arc welding, diameters 2.4 mm, 3.2 mm, 4.0 mm.

Which standards cover Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

Standard	Description
AWS A5.14	ERNiMo-7
ISO 18274	S Ni 1066
EN ISO 18274	S Ni 1066
DIN 1736	SG-NiMo28

General references: Nickel Institute · AMPP · SAE International · ASTM International

Chemical Composition of ERNiMo-7 Welding Wire (wt%)

Element	Content (%)
Nickel (Ni)	Balance
Molybdenum (Mo)	26.0 – 30.0
Iron (Fe)	2.0 max
Chromium (Cr)	1.0 max
Manganese (Mn)	1.0 max
Carbon (C)	0.02 max

What are the mechanical properties of Hastelloy B-2 (ERNiMo-7) Welding Wire Guide deposited metal?

Property	Typical Value
Tensile Strength	760 MPa (110 ksi) min
Yield Strength (0.2%)	400 MPa (58 ksi) min
Elongation	30% min
Service Temperature	up to 1040°C (1900°F)

Values above are typical for as-welded Hastelloy B-2 (ERNiMo-7) deposited metal under AWS A5.14 classification requirements. Actual results vary with welding process, heat input and shielding gas.

Why Choose Hastelloy B-2 Welding Wire

• Exceptional resistance to hydrochloric acid at all concentrations and temperatures — the benchmark alloy for HCl duty.
• Very low carbon and silicon minimise grain-boundary precipitation during welding.
• Resists sulphuric, acetic and phosphoric acid in reducing environments.
• Proven in catalyst recovery, acetic acid plant and pickle-line equipment.

What are the best practices for welding Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

Follow these practical guidelines to obtain sound, corrosion-resistant welds with this filler metal:

• Do NOT use in oxidising media or acids containing ferric or cupric salts — the alloy lacks sufficient chromium.
• Keep interpass temperature below 120°C (250°F) and avoid prolonged exposure to 550–850°C.
• Use argon shielding with generous coverage; molybdenum-rich weld metal oxidises readily when hot.
• Clean rigorously — sulphur, lead and phosphorus contamination causes weld cracking.

How do you select the right filler wire for Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

Hastelloy B-2 (ERNiMo-7) is the matching filler for its base alloy and is specified for joints where its particular corrosion or high-temperature performance is required. Match the wire form and diameter to the welding process and section thickness:

• GTAW (TIG): 1.6 mm or 2.0 mm wire for thin-wall pipe and root passes; 2.4 mm and 3.2 mm suit thicker sections and multi-pass filling.
• GMAW (MIG): 0.8-1.2 mm spooled wire gives high deposition for vessel and tank fabrication; 1.6 mm is better for heavy plate.
• SAW: 2.4-4.0 mm coils are preferred for long, straight welds on thick hydrochloric-acid vessels.

Restrict B-2 wire to reducing environments such as hydrochloric acid. For oxidising or mixed-acid duties, choose a chromium-bearing filler instead — compare Hastelloy B-3 for the most thermally stable option in the B-series.

Which base metals are compatible with Hastelloy B-2 (ERNiMo-7) Welding Wire Guide?

ERNiMo-7 is the matching consumable for Hastelloy B-2 and B-3 base metals, and it is also used to join nickel-molybdenum alloys to themselves and, with a suitable nickel buttering layer, to carbon steel. Because the weld metal is essentially chromium-free, it must be limited to reducing environments — hydrochloric, sulphuric and phosphoric acids — and kept away from oxidising media containing ferric or cupric ions.

How should Hastelloy B-2 (ERNiMo-7) Welding Wire Guide be stored, handled and certified?

Nickel-alloy filler metals are sensitive to moisture, surface contamination and trace impurities, so proper storage and handling are essential to weld integrity:

• Store spools and cut lengths in a clean, dry area and keep original packaging sealed until use to avoid condensation and humidity pickup.
• Remove oil, grease, sulphur, lead and phosphorus before welding — these impurities can cause hot cracking or embrittlement in nickel weld metal.
• Use dedicated stainless-steel wire brushes and tools reserved for nickel alloys only, to prevent iron contamination.
• For GTAW, keep the filler within the argon shield and maintain a short arc to prevent oxidation of the hot, molybdenum-rich weld pool.

Hangbo Alloy Group supplies Hastelloy B-2 (ERNiMo-7) welding wire with full EN 10204 3.1 material certificates, cast/lot traceability and chemical and mechanical test reports. Contact our sales team for batch-specific certification or technical support.

Frequently Asked Questions

Contact Us for Hastelloy B-2

Hangbo Alloy Group supplies Hastelloy B-2 (ERNiMo-7) welding wire with full material certifications. We ensure consistent wire quality with precise diameter control, clean surface finish, and uniform feeding performance.

For quotations, material certifications, or technical consultation, contact our sales team or call +86 13611656360.