Monel 400 Nuts manufactured at TorqBolt are corrosion resistant,high temperature resistant with ultimate tensile strength.
Dimensional standards as per ANSI B18.2.2 in imperial and ANSI B18.2.4.6M in metric are provided.
The raw material of these fasteners is renowned as registered trademarks like monel alloy 400. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. Monel 400 Nuts are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
Monel Alloy 400 Is A Nickel-copper Alloy That Has High Strength And Extreme Corrosion Resistance In A Range Of Media, Including Sea Water, Hydrofluoric Acid, Sulphuric Acid, Sulphuric Acid And Alkalis And Hence It Has Variety Of Industrial Applications. Used For Marine Engineering, Chemical And Hydrocarbon Processing Equipment, Valves, Pumps, Shafts, Fittings, Fasteners And Heat Exchangers.
Monel 400 nuts are internally threaded fasteners that mate with bolts and studs to form clamped joints. TorqBolt manufactures Monel 400 nuts per ASME B18.2.2, ISO 4032/4033/4034, DIN 934/EN 24032, and DIN 6915 (heavy hex), in sizes M6–M100 and 1/4"–4".
Nut Height Categories
Standard / regular hex nut — ~0.875×D height, ASME B18.2.2 Type 1
Heavy hex nut — ~D height, full strength matched to bolt grade (A194 2H pattern)
Jam / thin nut — 0.5×D height, used as locknut against a primary nut
Coupling nut — long-form for joining two threaded rods
Cap / acorn nut — closed-end, decorative + thread protection
Locking Variants
For vibration-loaded joints, Monel 400 nuts are available as nyloc (polymer insert), all-metal prevailing-torque (DIN 980, distorted-thread style), flange-serrated (DIN 6923, integral washer face with anti-back-off teeth), and castle / slotted (DIN 935, cotter-pin retention). Each locking style trades reusability against prevailing-torque retention.
Thread & Mechanical
Monel 400 nut threads are gauged per ASME B1.1 / ISO 965 to Class 2B / 6H by default; high-strength variants use 3B / 4H6H. Proof-load testing per ASTM F606 verifies the nut can develop the bolt's full strength without thread strip; hardness range is controlled to prevent stress-corrosion susceptibility (HV 250–353 typical for high-grade nuts). Each lot is EN 10204 3.1 / 3.2 certified.
Special Patterns
TorqBolt also produces Monel 400 nuts in weld-nut, T-nut, square-nut, knurled thumb-nut, and rivet-nut patterns. NACE MR0175 / ISO 15156 sour-service certification available; NORSOK M-650 qualified mills supplying high-temperature service grades.
Monel — Nickel-Copper Alloys
Monel alloys are 67% Ni / 33% Cu solid-solution alloys distinguished by uniform corrosion resistance in seawater, hydrofluoric acid, alkalis, and salt brines — environments where stainless steels fail by chloride pitting or copper-bearing alloys fail to alkalis. Monel was the first commercial nickel alloy and remains the default for offshore + chemical-processing fasteners requiring HF resistance.
Monel 400 (UNS N04400) is the base composition supplied in the as-annealed or hot-finished temper. Yield strength is moderate (~240 MPa min) but toughness extends to cryogenic service. Monel K-500 (N05500) adds Al + Ti for γ' precipitation hardening, raising yield to ~620 MPa after age hardening per AMS 4676 — the standard for high-strength shafting and fasteners in seawater. Monel R-405 is a free-machining variant.
Monel fasteners are produced per ASTM B164 (rod/bar) and supplied with EN 10204 3.1 / 3.2 certificates including stress-corrosion testing. Galvanic compatibility with copper-nickel piping makes Monel the natural mate for naval, desalination, and salt-evaporator service. NACE MR0175 sour-service compliance maintained when stress is below the SSC threshold for the specific heat-treat condition.
