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    A286 12-Point Fasteners

    A286 12-Point Fasteners, TorqBolt 12-point fastener with tB ligature and alloy grade marking

    A286 (UNS S66286) is a precipitation-hardening iron-nickel-chromium superalloy that is widely used in aerospace jet-engine fasteners, gas-turbine bolting, and nuclear reactor internals because it holds its 160 ksi tensile strength up to about 700 °C while remaining tough and corrosion-resistant. The 12-point head is the standard drive geometry on A286 aerospace bolts under MS21250, NAS1351, AS3216, NAS6303 through NAS6320 and AMS 5731 / AMS 5737 / AMS 5853 because it allows higher applied torque without camming the wrench off the head.

    TorqBolt manufactures the full 12-point geometry range in A286 (flange, head, cap-screw, stud) to AS9100D Rev D and ISO 9001:2015 quality systems, with NORSOK M-630 and NACE MR0175 / ISO 15156 qualifications for sour-service offshore applications. Each bolt head carries the struck tB manufacturer ligature plus the A286 grade marking, and every lot ships with a mill test report (MTC 3.1 standard, MTC 3.2 critical with third-party witness inspection).

    For deep A286 metallurgy, chemistry, heat treatment, and equivalent grades see alloya286.com.

    Specifications We Produce

    Typical Applications

    • Aerospace engine + structural bolting
    • Motorsport head studs, rod bolts, main cap bolts
    • Diesel-truck performance head studs
    • Industrial high-temperature bolting

    When to specify this alloy over alternatives

    Alloy choice in 12-point bolting is set by the combination of tensile target, service temperature, corrosion environment, and traceability requirement. The default for a generic 160 ksi aerospace bolt is A286 because the supply chain is mature, the AMS specs (5731 / 5732 / 5737) are well documented, and oxidation resistance is good to 700 deg C.

    Step up to Inconel 718 when service temperature exceeds 700 deg C or when the joint sees aggressive cyclic stress in jet-engine duty. Step up to MP35N when tensile target is 220+ ksi and the environment is sour-service or saline. Use Ti-6Al-4V when the 56 percent weight savings vs steel matters more than tensile (race-engine main caps, aerospace airframe pylon clip-ups). Use 17-4 PH H1025 when corrosion resistance and 180 ksi tensile both matter and budget rules out cobalt-nickel.

    Certification pack with each lot

    Mill test report MTC 3.1 ships with every lot at no additional cost: chemistry per the alloy spec, mechanical properties (tensile, yield, elongation at fracture, hardness), microstructure note, and heat-treatment cycle. MTC 3.2 adds third-party witness inspector signature on every test event from raw-bar receiving through final lot acceptance and is required by most aerospace primes for tier-1 critical-service joints. Add MTC 3.2 in the RFQ if your drawing or PO calls for it.

    Request a Quote

    RFQ to info@torqbolt.com or call +91-22-66157017. Mill test report (MTC 3.1 or 3.2 critical) ships with every lot.