ASME B18.3.1M Metric Socket Hex Cap Screws
ASME B18.3.1M Metric Socket Hex Cap Screws
Dimensions of ASME B18.3.1M Metric Socket Hex Cap Screws
| Nominal Size and Thread Pitch | Body Diameter, D | Head Diameter, A | Head Height, H | Chamfer or Radius, S, Max | Hexagon Socket Size, J, Nom. | Spline Socket Size, M, Nom. | Key Engagement, T, Min | Transition Diameter, Ba, Max | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Max | Min | Max | Min | Max | Min | ||||||
| M1.6 x 0.35 | 1.60 | 1.46 | 3.00 | 2.87 | 1.60 | 1.52 | 0.16 | 1.5 | 1.829 | 0.80 | 2.0 |
| M2 0.4 | 2.00 | 1.86 | 3.80 | 3.65 | 2.00 | 1.91 | 0.20 | 1.5 | 1.829 | 1.00 | 2.6 |
| M2.5 x 0.45 | 2.50 | 2.36 | 4.50 | 4.33 | 2.50 | 2.40 | 0.25 | 2.0 | 2.438 | 1.25 | 3.1 |
| M3 x 0.5 | 3.00 | 2.86 | 5.50 | 5.32 | 3.00 | 2.89 | 0.30 | 2.5 | 2.819 | 1.50 | 3.6 |
| M4 x 0.7 | 4.00 | 3.82 | 7.00 | 6.80 | 4.00 | 3.88 | 0.40 | 3.0 | 3.378 | 2.00 | 4.7 |
| M5 x 0.8 | 5.00 | 4.82 | 8.50 | 8.27 | 5.00 | 4.86 | 0.50 | 4.0 | 4.648 | 2.50 | 5.7 |
| M6 x 1 | 6.00 | 5.82 | 10.00 | 9.74 | 6.00 | 5.85 | 0.60 | 5.0 | 5.486 | 3.00 | 6.8 |
| M8 x 1.25 | 8.00 | 7.78 | 13.00 | 12.70 | 8.00 | 7.83 | 0.80 | 6.0 | 7.391 | 4.00 | 9.2 |
| M10 x 1.5 | 10.00 | 9.78 | 16.00 | 15.67 | 10.00 | 9.81 | 1.00 | 8.0 | -- | 5.00 | 11.2 |
| M12 x 1.75 | 12.00 | 11.73 | 18.00 | 17.63 | 12.00 | 11.79 | 1.20 | 10.0 | -- | 6.00 | 14.2 |
| M14 x 2b | 14.00 | 13.73 | 21.00 | 20.60 | 14.00 | 13.77 | 1.40 | 12.0 | -- | 7.00 | 16.2 |
| M16 x 2 | 16.00 | 15.73 | 24.00 | 23.58 | 16.00 | 15.76 | 1.60 | 14.0 | -- | 8.00 | 18.2 |
| M20 x 2.5 | 20.00 | 19.67 | 30.00 | 29.53 | 20.00 | 19.73 | 2.00 | 17.0 | -- | 10.00 | 22.4 |
| M24 x 3 | 24.00 | 23.67 | 36.00 | 35.48 | 24.00 | 23.70 | 2.40 | 19.0 | -- | 12.00 | 26.4 |
| M30 x 3.5 | 30.00 | 29.67 | 45.00 | 44.42 | 30.00 | 29.67 | 3.00 | 22.0 | -- | 15.00 | 33.4 |
| M36 x 4 | 36.00 | 35.61 | 54.00 | 43.37 | 36.00 | 35.64 | 3.60 | 27.0 | -- | 18.00 | 39.4 |
| M42 x 4.5 | 42.00 | 41.61 | 63.00 | 62.31 | 42.00 | 41.61 | 4.20 | 32.0 | -- | 21.00 | 45.6 |
| M48 x 5 | 48.00 | 47.61 | 72.00 | 71.27 | 48.00 | 47.58 | 4.80 | 36.0 | -- | 24.00 | 52.6 |
1.bThe M14X2 size is not recommended for use in new designs.
2.All dimensions are in millimeters
3.LG is a grip length and LB is body length.
4.For additional manufacturing and acceptance specificatons, see ASME B18.3.1M-1986.
