ASME B 18.5 - 2012 (2017) Round Head Fin Neck Bolts,(Inch Series) [Table 5] (A307, SAE J429, F468, F593)

Unit:

Thread Size
d

10#

1/4

5/16

d
PP	UNC
d_s	max
	min
d_k	max
	min
k	max
	min
n	max
	min
n₁	max
	min
k₁	max
	min

0.1900	0.2500	0.3125
24	20	18
0.199	0.260	0.324
0.182	0.237	0.298
0.469	0.594	0.719
0.438	0.563	0.688
0.114	0.145	0.176
0.094	0.125	0.156
0.098	0.114	0.145
0.078	0.094	0.125
0.395	0.458	0.551
0.375	0.438	0.531
0.088	0.104	0.135
0.076	0.094	0.125

①,Minimum Thread Length: The minimum length of thread shall be equal to twice the basic bolt diameter plus 0.25 in. for nominal bolt lengths of 6 in. or shorter, and twice the basic bolt diameter plus 0.50 in. for longer nominal lengths. Bolts of nominal lengths too short to accommodate the minimum thread lengths shall be threaded full length. The length from the head or neck to the first complete (full form) thread shall not exceed the length of 2-1/2 threads for sizes up to and including 1 in., and 3-1/2 threads for sizes over 1 in.