GOST 21249 (-1) – 1996 – Bu lông đầu vuông
Thread Size | 8 | 10 | 12 | 16 | 20 | 24 | 27 | 30 | 36 | 42 | ||
d | ||||||||||||
dc | max=nominal size | 12 | 14 | 18 | 23 | 29 | 35 | 41 | 44 | 48 | 56 | |
min | 11.57 | 13.57 | 17.57 | 22.48 | 28.48 | 34.38 | 40.38 | 43.38 | 47.38 | 55.26 | ||
dk | max=nominal size | 10 | 16 | 16 | 22 | 22 | 28 | 30 | 35 | 42 | 55 | |
min | 9.64 | 15.57 | 15.57 | 21.48 | 21.48 | 27.48 | 29.48 | 34.38 | 41.38 | 54.26 | ||
d1 | max=nominal size | 6 | 7 | 9 | 11 | 13 | 15 | 17 | 19 | 23 | 27 | |
min | 5.7 | 6.64 | 8.64 | 10.57 | 12.57 | 14.57 | 16.57 | 18.48 | 22.48 | 26.48 | ||
ds | max=nominal size | 6 | 8 | 9 | 13 | 16 | 19 | 22 | 25 | 30 | 36 | |
min | 5.7 | 7.64 | 8.64 | 12.57 | 15.57 | 18.48 | 21.48 | 24.48 | 29.48 | 35.38 | ||
h | 4 | 4 | 6 | 7 | 11 | 14 | 18 | 18 | 20 | 24 | ||
k | 6 | 10 | 10 | 14 | 14 | 19 | 22 | 22 | 25 | 30 | ||
m | 1 | 1 | 2 | 2 | 3 | 4 | 5 | 5 | 5 | 6 | ||
n | 2 | 2 | 4 | 4 | 4 | 5 | 5 | 5 | 5 | 6 | ||
s | 8 | 13 | 13 | 17 | 17 | 22 | 24 | 27 | 32 | 41 | ||
Weight of per 1000 steel products(≈kg) | – | – | – | – | – | – | – | – | – | – | ||
Length of Thread b | – | – | – | – | – | – | – | – | – | – |