ANSI ASME B18.3

Hexagon socket head cap screws

tech-ansi-asme-b18-3-p310




Size 0# 1# 2#
d Screw Diameter 0.06 0.073 0.086
PP UNC - 64 56
UNF 80 72 64
UNEF - - -
ds max=nominal size 0.06 0.073 0.086
min 0.0568 0.0695 0.0822
dk max 0.096 0.118 0.14
min 0.091 0.112 0.134
k max 0.06 0.073 0.086
min 0.057 0.07 0.083
s Nominal Size 0.05 0.062 0.078
t min 0.025 0.031 0.038
b min 0.5 0.62 0.62

Size 3# 4# 5#
d Screw Diameter 0.099 0.112 0.125
PP UNC 48 40 40
UNF 56 48 44
UNEF - - -
ds max=nominal size 0.099 0.112 0.125
min 0.0949 0.1075 0.1202
dk max 0.161 0.183 0.205
min 0.154 0.176 0.198
k max 0.099 0.112 0.125
min 0.095 0.108 0.121
s Nominal Size 0.078 0.094 0.094
t min 0.044 0.051 0.057
b min 0.62 0.75 0.75

Size 6# 8# 10#
d Screw Diameter 0.138 0.164 0.19
PP UNC 32 32 24
UNF 40 36 32
UNEF - - -
ds max=nominal size 0.138 0.164 0.19
min 0.1329 0.1585 0.184
dk max 0.226 0.27 0.312
min 0.218 0.262 0.303
k max 0.138 0.164 0.19
min 0.134 0.159 0.185
s Nominal Size 0.109 0.141 0.156
t min 0.064 0.077 0.09
b min 0.75 0.88 0.88

Size 1/4 5/16 3/8
d Screw Diameter 0.25 0.3125 0.375
PP UNC 20 18 16
UNF 28 24 24
UNEF 32 32 32
ds max=nominal size 0.25 0.3125 0.375
min 0.2435 0.3053 0.3678
dk max 0.375 0.469 0.562
min 0.365 0.457 0.55
k max 0.25 0.312 0.375
min 0.244 0.306 0.368
s Nominal Size 0.188 0.25 0.312
t min 0.12 0.151 0.182
b min 1 1.12 1.25

Size 7/16 1/2 5/8
d Screw Diameter 0.4375 0.5 0.625
PP UNC 14 13 11
UNF 20 20 18
UNEF 28 28 24
ds max=nominal size 0.4375 0.5 0.625
min 0.4294 0.4919 0.6163
dk max 0.656 0.75 0.938
min 0.642 0.735 0.921
k max 0.438 0.5 0.625
min 0.43 0.492 0.616
s Nominal Size 0.375 0.375 0.5
t min 0.213 0.245 0.307
b min 1.38 1.5 1.75

Size 3/4 7/8 1
d Screw Diameter 0.75 0.875 1
PP UNC 10 9 8
UNF 16 14 12
UNEF 20 20 20
ds max=nominal size 0.75 0.875 1
min 0.7406 0.8647 0.9886
dk max 1.125 1.312 1.5
min 1.107 1.293 1.479
k max 0.75 0.875 1
min 0.74 0.864 0.988
s Nominal Size 0.625 0.75 0.75
t min 0.37 0.432 0.495
b min 2 2.25 2.5

Size 1-1/8 1-1/4 1-3/8
d Screw Diameter 1.125 1.25 1.375
PP UNC 7 7 6
UNF 12 12 12
UNEF 18 18 18
ds max=nominal size 1.125 1.25 1.375
min 1.1086 1.2336 1.3568
dk max 1.688 1.875 2.062
min 1.665 1.852 2.038
k max 1.125 1.25 1.375
min 1.111 1.236 1.36
s Nominal Size 0.875 0.875 1
t min 0.557 0.62 0.682
b min 2.81 3.12 3.44

Size 1-1/2 1-3/4 2
d Screw Diameter 1.5 1.75 2
PP UNC 6 5 4.5
UNF 12 - -
UNEF 18 - -
ds max=nominal size 1.5 1.75 2
min 1.4818 1.7295 1.978
dk max 2.25 2.625 3
min 2.224 2.597 2.97
k max 1.5 1.75 2
min 1.485 1.734 1.983
s Nominal Size 1 1.25 1.5
t min 0.745 0.87 0.995
b min 3.75 4.38 5

Size 2-1/4 2-1/2 2-3/4
d Screw Diameter 2.25 2.5 2.75
PP UNC 4.5 4 4
UNF - - -
UNEF - - -
ds max=nominal size 2.25 2.5 2.75
min 2.228 2.4762 2.7262
dk max 3.375 3.75 4.125
min 3.344 3.717 4.09
k max 2.25 2.5 2.75
min 2.232 2.481 2.73
s Nominal Size 1.75 1.75 2
t min 1.12 1.245 1.37
b min 5.62 6.25 6.88

Size 3 3-1/4 3-1/2
d Screw Diameter 3 3.25 3.5
PP UNC 4 4 4
UNF - - -
UNEF - - -
ds max=nominal size 3 3.25 3.5
min 2.9762 3.2262 3.4762
dk max 4.5 4.875 5.25
min 4.464 4.837 5.211
k max 3 3.25 3.5
min 2.979 3.228 3.478
s Nominal Size 2.25 2.25 2.75
t min 1.495 1.62 1.745
b min 7.5 8.12 8.75

Size 3-3/4 4
d Screw Diameter 3.75 4
PP UNC 4 4
UNF - -
UNEF - -
ds max=nominal size 3.75 4
min 3.7262 3.9762
dk max 5.625 6
min 5.584 5.958
k max 3.75 4
min 3.727 3.976
s Nominal Size 2.75 3
t min 1.87 1.995
b min 9.38 10



All information is strictly informative