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  5. ASME B18.2.3.3m Heavy Hex Screws

ASME B18.2.3.3m Heavy Hex Screws

ASME B18.2.3.3m Heavy Hex Screws

Nominal Screw Dia., D , and Thread Pitch Body Diameter.,D s Width Across Flats,S Width Across Corners, E Head Height, K Wrenching Height, K 1 Washer Face Thickness,C Washer FaceDia.,D w
Max Min Max Min Max Min Max Min Min Max Min Min
ANSI B18.2.3.3M - M12 × 1.75 12 11.73 21 20.67 24.25 23.35 7.76 7.24 5.2 0.6 0.3 19.6
ANSI B18.2.3.3M - M14 × 2 14 13.73 24 23.67 27.71 26.75 9.09 8.51 6.2 0.6 0.3 22.5
ANSI B18.2.3.3M - M16 × 2 16 15.73 27 26.67 31.18 30.14 10.32 9.68 7 0.8 0.4 25.3
ANSI B18.2.3.3M - M20 × 2.5 20 19.67 34 33 39.26 37.29 12.88 12.12 8.8 0.8 0.4 31.4
ANSI B18.2.3.3M - M24 × 3 24 23.67 41 40 47.34 45.2 15.44 14.56 10.5 0.8 0.4 38
ANSI B18.2.3.3M - M30 × 3.5 30 29.67 50 49 57.74 55.37 19.48 17.92 13.1 0.8 0.4 46.6
ANSI B18.2.3.3M - M36 × 4 36 35.61 60 58.8 69.28 66.44 23.38 21.72 15.8 0.8 0.4 55.9
  • All dimensions are in millimeters.
  • Basic thread lengths, B, are the same as given in .
  • Transition thread length, X, includes the length of incomplete threads and tolerances on grip gaging
  • length and body length. It is intended for calculation purposes.
  • For additional manufacturing and acceptance specifications, reference should be made to the Standard.