ASME B18.5 Round Head Bolts

ASME B18.5 Round Head Bolts

Dimensions of ASME B18.5 Round Head Bolts

Nominal Size or Basic Bolt Diameter Body Diameter, E Head Diameter, A Head Height, H Maximum Fillet Radius, R
Max Min Max Min Max Min
No. 10 0.19 0.199 0.182 0.469 0.438 0.114 0.094 0.031
1/4 0.25 0.260 0.237 0.594 0.563 0.145 0.125 0.031
5/16 0.3125 0.324 0.298 0.719 0.688 0.176 0.156 0.031
3/8 0.375 0.388 0.360 0.844 0.782 0.208 0.188 0.031
7/16 0.4375 0.452 0.421 0.969 0.907 0.239 0.219 0.031
1/2 0.5 0.515 0.483 1.094 1.032 0.270 0.250 0.031
5/8 0.625 0.642 0.605 1.344 1.219 0.344 0.313 0.062
3/4 0.75 0.768 0.729 1.594 1.469 0.406 0.375 0.062
7/8 0.875 0.895 0.852 1.844 1.719 0.469 0.438 0.062
1 1 1.022 0.976 2.094 1.969 0.531 0.500 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.