Nimonic 90 U Bolts Specification

NIMONIC 90 Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| N07090 | – | 2.4632 | – | – | – |
Nimonic 90 U bolts are externally threaded fasteners with an integral head, manufactured per ASME B18.2.1, ISO 4014/4017, and DIN 933/931. TorqBolt produces Nimonic 90 U bolts in metric (M6–M100) and imperial (1/4"–4") diameters with custom lengths from 10 mm up to 3000 mm.
Nimonic 90 U bolts are supplied with full or partial threading. Full-thread (UNC, UNF, ISO metric coarse/fine) for tension-only joints; partial-thread shank for shear loads where the unthreaded grip carries the load. Thread fits per ASME B1.1 (Class 2A) or ISO 965 (6g) by default; tighter Class 3A / 4h6h fits available on request. Engagement length follows the 1.5×D rule for tapped holes; 1.0×D minimum on through-bolting.
Nimonic 90 U bolts achieve characteristic tensile strength, yield, and elongation per the source-material spec, with proof-load testing and hardness verification per ASTM F606 / ISO 898-1. Torque-tension calibration is published per ASME PCC-1 for critical joints. Each lot ships with EN 10204 3.1 (or 3.2 on request) certificates listing chemistry, mechanicals, hardness, and dimensional inspection.
TorqBolt can produce Nimonic 90 U bolts to drawing, with non-standard heads, drilled-shank variants, double-end, captive, or matched-set configurations. Coatings include zinc, PTFE, Xylan, hot-dip galvanized, and electroless nickel. NACE MR0175 / ISO 15156 sour-service certification on request.
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.