材质 
M6
1
11.05
10.29
9.71
10
9.78
M8
1.25
14.38
12.35
11.65
13
12.73
M10
1.5
17.77
16.35
15.65
16
15.73
M12
1.75
20.03
20.42
19.58
18
17.73
M16
2
26.75
25.42
24.58
24
23.67
M20
2.5
32.95
32.5
31.5
30
29.16
M24
3
39.85
38.5
37.5
36
35
M30
3.5
50.85
48.5
47.5
46
45
M36
4
60.79
55.6
54.4
55
53.8
M42
4.5
72.09
65.6
64.4
65
63.8
M48
5
82.6
75.6
74.4
75
73.1