A286 Stainless Steel Nuts manufactured at TorqBolt are high temperature and high strength iron based with high oxidation resistance.
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 classified as High temperature Austenitic Stainless Steel. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. A286 Stainless Steel Nuts are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
A286 stainless steel Fasteners are referred as high temperature bolting with co-efficient expansion similar to Austenitic Stainless Steel. A286 material specification is achieved by producing A286 steel in Argon oxygen decarburization (AOD) or vacuum Induction Melting Process that is further refined by Vacuum Arc Refining (VAR) or Electro Slag Refining (ESR) used for high nickel alloys like incoloy alloys. Comparable to incoloy, A286 can be age hardened with both oil quench and liquid quench conditions. Unlike other precipitation hardening steels, this A286 Steel requires Stress Rupture Testing with 100 hours minimum time to rupture. High temperature and low stress applications, good corrosion resistance at high temperatures are some of the most A286 Stainless Steel Properties. A286 steel is available in both solution treated condition and age hardened conditions.
A286 Stainless Steel nuts are internally threaded fasteners that mate with bolts and studs to form clamped joints. TorqBolt manufactures A286 Stainless Steel 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, A286 Stainless Steel 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
A286 Stainless Steel 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 A286 Stainless Steel 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.
A286 — Iron-Nickel-Chromium Superalloy
A-286 (UNS S66286, AISI 660) is an iron-nickel-chromium age-hardenable superalloy positioned between austenitic stainless steels and Inconel for high-temperature bolting at 700-1300°F (370-700°C). Approximately 26% Ni + 15% Cr + 1.25% Mo with Ti-Al precipitation hardening, A-286 retains tensile strength and oxidation resistance well beyond the limits of standard 316 SS while being substantially more economical than full nickel superalloys.
A-286 is the standard high-temperature stud and bolt material for steam turbines, gas-turbine combustor cases, exhaust systems, jet-engine shafts, and superheater bolting. The alloy responds to a two-step heat treatment: solution anneal at 980°C (water quench) followed by ageing at 720°C for ~16 hours, yielding tensile ~895 MPa and yield ~585 MPa with elongation >15%.
A-286 fasteners are supplied per ASTM A453 grade 660 (with class A/B/C/D heat-treat conditions) and AMS 5731 / 5732 / 5734 / 5737. EN 10204 3.1 / 3.2 certification covers chemistry, mechanicals at room temperature + elevated test temperatures, hardness (HRC 24-35), and stress-rupture testing. NACE MR0175 / ISO 15156 sour-service compliance is achievable in specific heat-treat conditions; A-286 is widely qualified for downhole + wellhead bolting.
