NIMONIC 90 Coupling Nuts manufactured at TorqBolt are corrosion resistant,high temperature resistant with ultimate tensile strength.
Dimensional standards as per DIN 439B,DIN 6334,ISO 898-2,DIN 3871,DIN 8434-117 are provided.
The raw material of these fasteners is further classified as Super Nickel Alloys. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. NIMONIC 90 Coupling Nuts are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
Nimonic 90 Coupling nuts are internally threaded fasteners that mate with bolts and studs to form clamped joints. TorqBolt manufactures Nimonic 90 Coupling 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, Nimonic 90 Coupling 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
Nimonic 90 Coupling 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 Nimonic 90 Coupling 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.
Nimonic — Nickel-Chromium Wrought Superalloys
Nimonic is a family of wrought nickel-chromium superalloys originally developed for jet-engine turbine blade and bolting service, where steady-state operating temperatures exceed 700°C under high cyclic stress. Composition centers on ~50-75% Ni, 15-22% Cr, 0-20% Co with Ti+Al additions for γ' precipitation hardening. Nimonic alloys retain creep strength well beyond the limits of conventional Fe-Ni-Cr superalloys.
Nimonic 75 (UNS N06075) is the simplest grade: solid-solution Ni-Cr without precipitation hardening, used for furnace fixtures and mild-temperature bolting to 760°C. Nimonic 80A (N07080) adds Ti+Al for age-hardening — tensile ~1100 MPa, the workhorse of steam-turbine and exhaust-valve bolting per ASTM B637 / AMS 5662. Nimonic 90 (N07090) adds 16-20% Co for service to 920°C with stress-rupture life suitable for gas-turbine combustor bolts.
Nimonic fasteners ship per ASTM B637 / B564 with EN 10204 3.1 / 3.2 certs covering chemistry, hardness (HRC 30-42), tensile at room + elevated temperature, and stress-rupture acceptance per the heat-treat condition. NACE MR0175 sour-service compliance available in solution-annealed condition.
