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    ASTM F467/F467M Grade N10276 Alloy 276 Nuts Specification

    Corrosion-resistant nickel alloy nuts for chemical and marine industries.

    ASTM F467/F467M Grade N10276 Alloy 276 Nuts provide outstanding resistance against pitting, crevice corrosion, and harsh chemical exposure in critical industrial applications.

    ASTM F467/F467M Chemical Composition

    ASTM F467/F467M Nickel and Nickel-Base Alloys

    UNS Designation Number Alloy General Name Al C, max Cr Cu A Fe, max Mn, max Ni A P, max Si, max Ti Co, max Mo S, max V W Cb
    ASTM F467/F467M Grade N10276 276 Ni-Mo-Cr . . . 0.02 14.5- 16.5 . . . 4.0- 7.0 1.00 balance 0.040 0.08 . . . 2.50 15.0- 17.0 0.030 0.35 max 3.0- 4.5 . . .
    • (A) Elements shown as balance shall be arithmetically computed by deducting the sum of the other named elements from 100.
    • (B) Cobalt is to be counted as nickel.

    ASTM F467/F467M Mechanical Requirements

    ASTM F467/F467M Mechanical Requirements (Inch)

    Alloy Mechanical Property Marking Hardness, min A Proof Stress, Hex Nut min, ksi Proof Stress, Heavy Hex Nut min, ksi B
    ASTM F467 Alloy Ni 276 F 467T 20 HRC 110 119
    • (B) Proof stress values for heavy hex nuts are based on 1.08 times the value for corresponding regular hex nuts.

    ASTM F467M Mechanical Requirements (Metric)

    Alloy Mechanical Property Marking Hardness, min A Proof Stress, Mpa
    ASTM F467M Ni 276 F467MT 20 HRC 760

    ASTM F467/F467M Tensile Stress Areas and Threads per Inch

    Nominal Size, in. Coarse Threads-UNC Fine Threads-UNF 8 Thread Series-8UN
    Threads/in. Stress Area A, in 2 Threads/in. Stress Area A, in 2 Threads/in. Stress Area A, in 2
    1/ 4 20 0.0318 28 0.0364 . . . . . .
    5/ 16 18 0.0524 24 0.0580 . . . . . .
    3/ 8 16 0.0775 24 0.0878 . . . . . .
    7/ 16 14 0.1063 20 0.1187 . . . . . .
    1/ 2 13 0.1419 20 0.1599 . . . . . .
    9/ 16 12 0.1820 18 0.2030 . . . . . .
    5/ 8 11 0.2260 18 0.2560 . . . . . .
    3/ 4 10 0.3340 16 0.3730 . . . . . .
    7/ 8 9 0.4620 14 0.5090 . . . . . .
    1 8 0.6060 12 0.6630 . . . . . .
    1 1/ 8 7 0.7630 12 0.8560 8 0.790
    1 1/ 4 7 0.9690 12 1.0730 8 1.000
    1 3/ 8 6 1.1550 12 1.3150 8 1.233
    1 1/ 2 6 1.4050 12 1.5810 8 1.492
    • (A) Tensile stress areas are computed using the following formula:
    • A s = 0.7854 [ D - 0.9743/n ]
      • where:
      • As = tensile stress area, in. 2 ,
      • D = nominal size (basic major diameter), in., and
      • n = number of threads per inch.

    ASTM F467/F467M Tensile Stress Areas and Threads per Metric

    Nominal Nut Diameter and Thread Pitch Stress Area, Amm 2 Nominal Nut Diameter and Thread Pitch Stress Area, Amm 2
    M6 × 1 20.1 M16 × 2 157
    M8 × 1.25 36.6 M20 × 2.5 245
    M10 × 1.5 58.0 M24 × 3 353
    M12 × 1.75 84.3 M30 × 3.5 561
    M14 × 2 115 M36 × 4 817
    • (A) Tensile stress areas are computed using the following formula:
    • As = 0.7854 (D − 0.9382P) 2
      • where:
      • As = tensile stress area, mm. 2 ,
      • D = nominal size (basic major diameter), mm., and
      • n = number of threads per mm.

    ASTM F467/F467M Heat Treatment

    Alloy Condition
    Copper (all alloys) As formed or stress relieved at manufacturer's option
    Nickel alloys 400 and 405 As formed or stress relieved at manufacturer's option
    Nickel alloy 500 Solution annealed and aged
    Aluminum alloy 2024-T4 Solution treated and naturally aged
    Aluminum alloy 6061-T6 Solution treated and artificially aged
    Aluminum alloy 6262-T9 Solution treated, artificially aged, and cold worked
    Titanium 625 Annealed

    Frequently Asked Questions

    What is Hastelloy C-276 (N10276)?

    Hastelloy C-276 is a Ni-Cr-Mo-W alloy (~57 Ni, 15.5 Cr, 16 Mo, 3.7 W) and the workhorse high-performance corrosion-resistant alloy for mixed oxidizing + reducing chemistry, chloride pitting + crevice corrosion, FGD scrubbers, and pharmaceutical / agrochemical reactors. Per ASTM F467 across the full nut dimensional range.

    Is Hastelloy C-276 NACE MR0175 acceptable for sour service?

    Yes. N10276 is one of the most widely-specified NACE MR0175 / ISO 15156-listed nickel alloys for downhole and surface nut in severe H2S + chloride sour service.

    How does C-276 perform vs duplex stainless in seawater?

    Super-duplex (S32750, S32760) reaches PREN ~42; C-276 PREN equivalent is ~70. For aggressive chloride pitting service (warm sea water with crevices, FGD scrubber service, etc.), C-276 dominates. For routine clean seawater, super-duplex is the lower-cost choice. F467 covers C-276 only; super-duplex nut goes through ASTM A1082.

    Where is Hastelloy C-276 most often specified in F467 nut applications?

    Subsea oilfield equipment, FGD scrubber internals, pharmaceutical reactor manholes, chlorine + bleach plant bolting, geothermal power generation. Available in all ASME B16 and B18 dimensional patterns per F467.

    References & Standards

    • ASTM F467 / F467M - Standard Specification for Nonferrous Nuts for General Use
    • ASTM F468 / F468M - Companion specification for Nonferrous Bolts, Hex Cap Screws, and Studs (mate with F467 nuts for matched-alloy assemblies)
    • ASTM F436 / F436M - Hardened steel washers (ferrous washer companion when nonferrous washers are not specified)
    • NACE MR0175 / ISO 15156 - Sour-service hardness limits for petroleum and natural gas industries
    • ASME B18.2.2 / B18.2.4.1M / B18.2.4.6M and ISO 4032 / 4033 / 4035 - Dimensional standards referenced by F467
    • DIN 934 / 439 / 6330 - Metric hex nut dimensional standards