ASME B18.5 Round Head Square Neck Bolts

ASME B18.5 Round Head Square Neck Bolts

Dimensions of ASME B18.5 Round Head Square Neck Bolts

Nominal Size or Basic Bolt Diameter Body Diameter, E Head Diameter, A Head Height, H Square Width, O Square Depth, P Corner Radius on Square, Q Fillet Radius, R
Max Min Max Min Max Min Max Min Max Min Max Max2
No. 10 0.1900 0.199 0.182 0.469 0.436 0.114 0.094 0.199 0.185 0.125 0.094 0.031 0.031
1/4 0.2500 0.260 0.237 0.594 0.563 0.145 0.125 0.260 0.245 0.156 0.125 0.031 0.031
5/16 0.3125 0.324 0.298 0.719 0.688 0.176 0.156 0.324 0.307 0.187 0.156 0.031 0.031
3/8 0.3750 0.388 0.360 0.844 0.782 0.208 0.188 0.388 0.368 0.219 0.188 0.047 0.031
7/16 0.4375 0.452 0.421 0.969 0.907 0.239 0.219 0.452 0.431 0.250 0.219 0.047 0.031
1/2 0.5000 0.515 0.483 1.094 1.032 0.270 0.250 0.515 0.492 0.281 0.250 0.047 0.031
5/8 0.6250 0.642 0.605 1.344 1.219 0.344 0.313 0.642 0.616 0.344 0.313 0.078 0.062
3/4 0.7500 0.768 0.729 1.594 1.469 0.406 0.375 0.768 0.741 0.406 0.375 0.078 0.062
7/8 0.8750 0.895 0.852 1.844 1.719 0.459 0.438 0.895 0.865 0.469 0.438 0.094 0.062
1 1.0000 1.022 0.976 2.094 1.969 0.531 0.500 1.022 0.990 0.531 0.500 0.094 0.062

Note :

  • Where specifying nominal size in decimals, zeros preceding decimal and in the fourth decimal place shall be omitted.
  • The minimum radius is one half of the value shown.