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ASME B18.2.2 Hex Coupling Nuts

ASME B18.2.2 Hex Coupling Nuts

ASME B18.2.2 Hex Coupling Nuts Dimensions (mm)

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 3.505 7.938 7.671 7.925 8.738 9.169 12.700 11.938 12.954
ASME B18.2.2 - #8 4.166 7.938 7.671 7.925 8.738 9.169 15.875 15.113 16.383
ASME B18.2.2 - #10 4.826 7.938 7.671 7.925 8.738 9.169 19.050 18.059 19.304
ASME B18.2.2 - 1⁄4 6.350 11.113 10.871 11.125 12.395 12.827 44.450 42.926 44.704
ASME B18.2.2 - 5⁄16 7.925 12.700 12.421 12.700 14.148 14.656 44.450 42.926 44.704
ASME B18.2.2 - 3⁄8 9.525 14.288 13.995 14.275 15.951 16.510 44.450 42.926 44.704
ASME B18.2.2 - 7⁄16 11.100 15.875 15.418 15.875 17.577 18.339 44.450 42.926 44.704
ASME B18.2.2 - 1⁄2 12.700 17.463 16.840 17.475 19.202 20.168 44.450 42.926 44.704
ASME B18.2.2 - 9 ⁄16 14.275 20.638 19.863 20.650 22.631 23.851 53.975 52.502 54.229
ASME B18.2.2 - 5⁄8 15.875 20.638 19.863 20.650 22.631 23.851 53.975 52.502 54.229
ASME B18.2.2 - 3⁄4 19.050 25.400 24.460 25.400 27.864 29.337 57.150 55.626 57.404
ASME B18.2.2 - 7⁄8 22.225 31.750 30.785 31.750 35.103 36.652 63.500 61.976 63.754
ASME B18.2.2 - 1 25.400 34.925 33.655 34.925 38.379 40.335 69.850 68.326 70.104
ASME B18.2.2 - 1 1⁄8 28.575 38.100 36.830 38.100 41.986 43.993 76.200 74.676 76.454
ASME B18.2.2 - 1 1⁄4 31.750 41.275 40.005 41.275 46.355 47.650 76.200 74.676 76.454
ASME B18.2.2 - 1 1⁄2 38.100 50.800 49.530 50.800 57.785 58.649 88.900 87.376 89.154
ASME B18.2.2 - 1 5⁄8 41.275 65.088 63.017 65.075 71.831 75.159 123.825 122.682 124.714
ASME B18.2.2 - 1 3⁄4 44.450 69.850 67.615 69.850 77.089 80.645 133.350 132.334 134.366
ASME B18.2.2 - 1 7⁄8 47.625 74.613 72.238 74.625 82.347 86.157 142.875 141.732 144.018
ASME B18.2.2 - 2 50.800 79.375 76.835 79.375 87.579 91.643 152.400 151.130 153.416
ASME B18.2.2 - 2 1⁄4 57.150 88.900 86.055 88.900 98.095 102.641 171.450 170.180 172.720
ASME B18.2.2 - 2 1⁄2 63.500 98.425 95.250 98.425 108.585 113.640 190.500 188.976 191.770
ASME B18.2.2 - 2 3⁄4 69.850 107.950 104.445 107.950 119.075 124.638 209.550 208.026 211.074
ASME B18.2.2 - 3 76.200 117.475 113.665 117.475 129.565 135.636 228.600 227.076 230.124
ASME B18.2.2 - 3 1⁄4 82.550 127.000 122.885 127.000 140.081 146.634 247.650 245.872 249.174
ASME B18.2.2 - 3 1⁄2 88.900 136.525 132.080 136.525 150.571 157.632 266.700 264.922 268.478
ASME B18.2.2 - 3 3⁄4 95.250 146.050 141.275 146.050 161.036 168.631 285.750 283.718 287.528
ASME B18.2.2 - 4 101.600 155.575 150.495 155.575 171.552 179.629 304.800 302.768 306.832
ASME B18.2.2 - 4 1⁄4 107.950 165.100 159.715 165.100 182.067 190.652 323.850 321.818 325.882
ASME B18.2.2 - 4 1⁄2 114.300 174.625 168.910 174.625 192.557 201.651 342.900 340.868 344.932
ASME B18.2.2 - 4 3⁄4 120.650 184.150 178.105 184.150 203.048 212.649 361.950 359.664 364.236
ASME B18.2.2 - 5 127.000 193.675 187.325 193.675 213.563 223.647 381.000 378.714 383.286
ASME B18.2.2 - 5 1⁄4 133.350 203.200 196.545 203.200 224.053 234.645 400.050 397.510 402.590
ASME B18.2.2 - 5 1⁄2 139.700 212.725 205.740 212.725 234.544 245.643 419.100 416.560 421.640
ASME B18.2.2 - 5 3⁄4 146.050 222.250 214.935 222.250 245.034 256.642 438.150 435.610 440.690
ASME B18.2.2 - 6 152.400 231.775 224.155 231.775 255.524 267.640 457.200 454.406 459.994
  • 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 2 1⁄2 in. and smaller, and 1 in. for sizes 2 3⁄4 in. and larger.

ASME B18.2.2 Hex Coupling Nuts Dimensions (Inch)

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.