Incoloy 800 Wing Nuts Specification

Incoloy 800 Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| N08800 | – | 1.4558 | X2nicralti32-20 | – | Ncf 800 |
Incoloy 800 Wing nuts are internally threaded fasteners that mate with bolts and studs to form clamped joints. TorqBolt manufactures Incoloy 800 Wing 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, Incoloy 800 Wing 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.
Incoloy 800 Wing 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 Incoloy 800 Wing 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.
Incoloy is the family of nickel-iron-chromium alloys positioned between stainless steels (low Ni) and Inconel superalloys (low Fe). Incoloy combines the high-temperature strength of nickel alloys with cost savings from iron substitution — the working-class superalloy.
Incoloy 800 (UNS N08800) and the modified Incoloy 800H / 800HT grades (controlled C, Al+Ti chemistry) are the most widely specified for heat-treating fixtures, ethylene-cracking furnace tubes, and steam-superheater bolting up to 1100°C. Incoloy 825 (N08825) adds Mo + Cu to deliver outstanding resistance to sulfuric, phosphoric, and reducing acids — the default for mineral-acid service and pickling-line fasteners. Incoloy 925 (N09925) is age-hardenable for high-strength sour-service applications, qualified to NACE MR0175.
Incoloy fasteners are supplied per ASTM B408 (rod/bar) and ASTM B564 (forged), with EN 10204 3.1 / 3.2 certification covering chemistry, mechanicals, intergranular corrosion (ASTM G28), and grain size. Welding uses matching filler (ENiCrMo-3 type for 800/825); post-weld solution-anneal at ~980°C restores corrosion resistance in heavy sections.