材质 
M5
0.8
11.8
8.79
6.2
5.7
8
7.78
1
M6
1
14.2
11.05
7.3
6.8
10
9.78
1.1
M8
1.25
17.9
14.38
9.4
8.74
13
12.73
1.25
M10
1.5
21.8
16.64
11.4
10.34
15
14.73
1.5
M12
1.75
26
20.03
13.8
12.57
18
17.73
1.8
M14
2
29.9
23.36
15.9
14.8
21
20.67
2.1
M16
2
34.5
26.75
18.3
17.2
24
23.67
2.4
M20
2.5
42.8
32.95
22.4
20.3
30
29.16
3