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ASME B18.2.2 Hex Coupling Nuts

ASME B18.2.2 Hex Coupling Nuts

Nominal Size Basic Major Diameter of Thread Width Across Flats, F Width Across Corners, G Length, H
Basic Min. Max. Min. Max. Basic Min. Max.
ASME B18.2.2 - #6 0.138 5⁄16 0.302 0.312 0.344 0.361 1⁄2 0.470 0.510
ASME B18.2.2 - #8 0.164 5⁄16 0.302 0.312 0.344 0.361 5⁄8 0.595 0.645
ASME B18.2.2 - #10 0.19 5⁄16 0.302 0.312 0.344 0.361 3⁄4 0.711 0.760
ASME B18.2.2 - 1⁄4 0.25 7⁄16 0.428 0.438 0.488 0.505 1 3⁄4 1.690 1.760
ASME B18.2.2 - 5⁄16 0.312 1⁄2 0.489 0.5 0.557 0.577 1 3⁄4 1.690 1.760
ASME B18.2.2 - 3⁄8 0.375 9⁄16 0.551 0.562 0.628 0.65 1 3⁄4 1.690 1.760
ASME B18.2.2 - 7⁄16 0.437 5⁄8 0.607 0.625 0.692 0.722 1 3⁄4 1.690 1.760
ASME B18.2.2 - 1⁄2 0.5 11⁄16 0.663 0.688 0.756 0.794 1 3⁄4 1.690 1.760
ASME B18.2.2 - 9 ⁄16 0.562 13⁄16 0.782 0.813 0.891 0.939 2 1⁄8 2.067 2.135
ASME B18.2.2 - 5⁄8 0.625 13⁄16 0.782 0.813 0.891 0.939 2 1⁄8 2.067 2.135
ASME B18.2.2 - 3⁄4 0.75 1 0.963 1 1.097 1.155 2 1⁄4 2.190 2.260
ASME B18.2.2 - 7⁄8 0.875 11⁄4 1.212 1.25 1.382 1.443 2 1⁄2 2.440 2.510
ASME B18.2.2 - 1 1 1 3⁄8 1.325 1.375 1.511 1.588 2 3⁄4 2.690 2.760
ASME B18.2.2 - 1 1⁄8 1.125 11⁄2 1.45 1.5 1.653 1.732 3 2.940 3.010
ASME B18.2.2 - 1 1⁄4 0.125 15⁄8 1.575 1.625 1.825 1.876 3 2.940 3.010
ASME B18.2.2 - 1 1⁄2 1.5 2 1.95 2 2.275 2.309 3 1⁄2 3.440 3.510
ASME B18.2.2 - 1 5⁄8 1.625 29⁄16 2.481 2.562 2.828 2.959 4 7⁄8 4.830 4.910
ASME B18.2.2 - 1 3⁄4 1.75 23⁄4 2.662 2.75 3.035 3.175 5 1⁄4 5.210 5.290
ASME B18.2.2 - 1 7⁄8 1.875 2 15⁄16 2.844 2.938 3.242 3.392 5 5⁄8 5.580 5.670
ASME B18.2.2 - 2 2 3 1⁄8 3.025 3.125 3.448 3.608 6 5.950 6.040
ASME B18.2.2 - 2 1⁄4 2.25 31⁄2 3.388 3.5 3.862 4.041 6 3⁄4 6.700 6.800
ASME B18.2.2 - 2 1⁄2 2.5 37⁄8 3.75 3.875 4.275 4.474 7 1⁄2 7.440 7.550
ASME B18.2.2 - 2 3⁄4 2.75 41⁄4 4.112 4.25 4.688 4.907 8 1⁄4 8.190 8.310
ASME B18.2.2 - 3 3 4 5⁄8 4.475 4.625 5.101 5.34 9 8.940 9.060
ASME B18.2.2 - 3 1⁄4 3.25 5 4.838 5 5.515 5.773 9 3⁄4 9.680 9.810
ASME B18.2.2 - 3 1⁄2 3.5 53⁄8 5.2 5.375 5.928 6.206 10 1⁄2 10.430 10.570
ASME B18.2.2 - 3 3⁄4 3.75 53⁄4 5.562 5.75 6.34 6.639 11 1⁄4 11.170 11.320
ASME B18.2.2 - 4 4 6 1⁄8 5.925 6.125 6.754 7.072 12 11.920 12.080
ASME B18.2.2 - 4 1⁄4 4.25 61⁄2 6.288 6.5 7.168 7.506 12 3⁄4 12.670 12.830
ASME B18.2.2 - 4 1⁄2 4.5 67⁄8 6.65 6.875 7.581 7.939 13 1⁄2 13.420 13.580
ASME B18.2.2 - 4 3⁄4 4.75 71⁄4 7.012 7.25 7.994 8.372 14 1⁄4 14.160 14.340
ASME B18.2.2 - 5 5 7 5⁄8 7.375 7.625 8.408 8.805 15 14.910 15.090
ASME B18.2.2 - 5 1⁄4 5.25 8 7.738 8 8.821 9.238 15 3⁄4 15.650 15.850
ASME B18.2.2 - 5 1⁄2 5.5 83⁄8 8.1 8.375 9.234 9.671 16 1⁄2 16.400 16.600
ASME B18.2.2 - 5 3⁄4 5.75 83⁄4 8.462 8.75 9.647 10.104 17 1⁄4 17.150 17.350
ASME B18.2.2 - 6 6 9 1⁄8 8.825 9.125 10.06 10.537 18 17.890 18.110
  • GENERAL NOTES:
    • (a) For additional requirements, refer to section 3, General Data.
    • (b) Concentricity of Tapped Hole. Axis of tapped hole shall be concentric with axis of nut body within a tolerance equal to 3% (6% FIM) of the maximum width across flats.
    • (c) Countersink. Tapped hole may be countersunk on both faces.
    • (d) When specified by the purchaser, different thread sizes or series shall be tapped into the nut from opposite ends with each thread extending to approximately 0.5H. All other nut dimensions shall comply with Table 13 unless otherwise agreed to by the supplier and purchaser.
    • (e) The dimensions in Table 13 are considered standard, but purchasers may specify across flats sizes and/or lengths that differ from this table.
    • (f) Hex coupling nuts must conform to the proof load requirements of ASTM A 563, Grade A for heavy hex nuts.
  • NOTE:
    • (1) Nuts shall be furnished without a hole, unless specially ordered by the purchaser. In some applications it may be desirable to assure that the threaded parts joined by a coupling nut are each engaged to approximately one-half nut thickness. As a visual inspection aid, a hole drilled through one side of the nut is recommended. The hole should be located at mid-nut thickness,and have a diameter of 0.2 to 0.4 times nominal nut size for sizes 21⁄2 in. and smaller, and 1 in. for sizes 2 3⁄4 in. and larger.