ISO 12474

Hexagon socket head cap screws

metric fine pitch thread

tech-iso12474




Thread Size
d		 M8 M10 M12
P Thread Pitch Fine thread 1 1 1 1.5
Fine thread 2 / 1.25 1.25
dk max For plain heads 13 16 18
For knurled heads 13.27 16.27 18.27
min 12.73 15.73 17.73
ds max 8 10 12
min 7.78 9.78 11.73
k max 8 10 12
min 7.64 9.64 11.57
s max 6.14 8.175 10.175
min 6.02 8.025 10.025
t min 4 5 6
Length of Thread b 28 32 36

Thread Size
d		 M14 M16 M20
P Thread Pitch Fine thread 1 / 1.5 2
Fine thread 2 1.5 / 1.5
dk max For plain heads 21 24 30
For knurled heads 21.33 24.33 30.33
min 20.67 23.67 29.67
ds max 14 16 20
min 13.73 15.73 19.67
k max 14 16 20
min 13.57 15.57 19.48
s max 12.212 14.212 17.23
min 12.032 14.032 17.05
t min 7 8 10
Length of Thread b 40 44 52

Thread Size
d		 M24 M30 M36
P Thread Pitch Fine thread 1 2 2 3
Fine thread 2 / / /
dk max For plain heads 36 45 54
For knurled heads 36.39 45.39 54.46
min 35.61 44.61 53.54
ds max 24 30 36
min 23.67 29.67 35.61
k max 24 30 36
min 23.48 29.48 35.38
s max 19.275 22.275 27.275
min 19.065 22.065 27.065
t min 12 15.5 19
Length of Thread b 60 72 84



*not standardized, reference values


All information is strictly informative