Nimonic 80a Nylon Lock Nuts Specification

NIMONIC 80A Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| N07080 | – | 2.4631 | – | – | – |
Nimonic 80a Nylon Lock nuts are internally threaded fasteners that mate with bolts and studs to form clamped joints. TorqBolt manufactures Nimonic 80a Nylon Lock 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".
For vibration-loaded joints, Nimonic 80a Nylon Lock 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.
Nimonic 80a Nylon Lock 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.
TorqBolt also produces Nimonic 80a Nylon Lock 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 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.