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  4. ASME B18.5 114 Degree Countersunk Square Neck Bolts

ASME B18.5 114 Degree Countersunk Square Neck Bolts

ASME B18.5 114 Degree Countersunk Square Neck Bolts

Nominal Size Body Dia., E Corner Rad. on Square, Q Width of Square, O Depth of Square, P Dia. of Head, A Flat on Head, F Height of Head, H
Max. Min. Max. Min. Min. Max. Min. Max. Min. Min. Max. Min.
ASME B18.5 - No. 10 0.199 0.182 0.031 0.199 0.185 0.125 0.094 0.548 0.5 0.015 0.131 0.112
ASME B18.5 - 1⁄4 0.26 0.237 0.031 0.26 0.245 0.156 0.125 0.682 0.625 0.018 0.154 0.135
ASME B18.5 - 5⁄16 0.324 0.298 0.031 0.324 0.307 0.219 0.188 0.821 0.75 0.023 0.184 0.159
ASME B18.5 - 3⁄8 0.388 0.36 0.047 0.388 0.368 0.25 0.219 0.96 0.875 0.027 0.212 0.183
ASME B18.5 - 7⁄16 0.452 0.421 0.047 0.452 0.431 0.281 0.25 1.093 1 0.03 0.235 0.205
ASME B18.5 - 1⁄2 0.515 0.483 0.047 0.515 0.492 0.312 0.281 1.233 1.125 0.035 0.265 0.229
ASME B18.5 - 5⁄8a 0.642 0.605 0.078 0.642 0.616 0.406 0.375 1.495 1.375 0.038 0.316 0.272
ASME B18.5 - 3⁄4a 0.768 0.729 0.078 0.768 0.741 0.5 0.469 10.754 1.625 0.041 0.368 0.314
  • a These sizes pertain to 114 degree countersunk square neck bolts only. Dimensions given in last seven columns to the right are for these bolts only.
  • All dimensions are in inches unless otherwise specified.
  • Threads are Unified Standard, Class 2A, UNC Series, in accordance with ANSI B1.1. For threads with additive finish, the maximum diameters of Class 2A shall
  • apply before plating or coating, whereas the basic diameters (Class 2A maximum diameters plus the allowance) shall apply to a bolt after plating or coating.
  • Bolts are designated in the sequence shown: nominal size (number, fraction or decimal equivalent); threads per inch; nominal length (fraction or decimal equivalent); product name; material; and protective finish, if required.
  • For example 1⁄2 - 13 × 3 Round Head Square Neck Bolt, Steel .375-16 × 2.50 Step Bolt, Steel, Zinc Plated