开槽凹端紧定螺钉 (摘自GB 74-85)
螺纹规格为M1.6～M12的开槽凹端紧定螺钉。
标记示例：
螺纹规格d=M5、公称长度l=12mm、性能等级为14H级、表面氧化的开槽凹端紧定螺钉的标记：
螺钉 GB 74 M5×12
螺纹规格为M1.6～M12的开槽凹端紧定螺钉：
螺纹规格
d
|
P
|
df≈
|
dz
|
n
|
t
|
l
|
min
|
max
|
公称
|
min
|
max
|
min
|
max
|
M1.6
|
0.35
|
1.6
|
0.55
|
0.8
|
0.25
|
0.31
|
0.45
|
0.56
|
0.74
|
2～8
|
M2
|
0.4
|
2
|
0.75
|
1
|
0.25
|
0.31
|
0.45
|
0.64
|
0.84
|
2.5～10
|
M2.5
|
0.45
|
2.5
|
0.95
|
1.2
|
0.4
|
0.46
|
0.6
|
0.72
|
0.95
|
3～12
|
M3
|
0.5
|
3
|
1.15
|
1.4
|
0.4
|
0.46
|
0.6
|
0.8
|
1.05
|
3～16
|
M4
|
0.7
|
4
|
1.75
|
2
|
0.6
|
0.66
|
0.8
|
1.12
|
1.42
|
4～20
|
M5
|
0.8
|
5
|
2.25
|
2.5
|
0.8
|
0.86
|
1
|
1.28
|
1.63
|
5～25
|
M6
|
1
|
6
|
2.75
|
3
|
1
|
1.06
|
1.2
|
1.6
|
2
|
6～30
|
M8
|
1.25
|
8
|
4.7
|
5
|
1.2
|
1.26
|
1.51
|
2
|
2.5
|
8～40
|
M10
|
1.5
|
10
|
5.7
|
6
|
1.6
|
1.66
|
1.91
|
2.4
|
3
|
10～50
|
M12
|
1.75
|
12
|
7.7
|
8
|
2
|
2.06
|
2.31
|
2.8
|
3.6
|
12～60
|
l的范围：
公称
|
2
|
2.5
|
3
|
4
|
5
|
6
|
8
|
10
|
12
|
(14)
|
16
|
20
|
25
|
30
|
35
|
40
|
45
|
50
|
(55)
|
60
|
min
|
1.8
|
2.3
|
2.8
|
3.7
|
4.7
|
5.7
|
7.7
|
9.7
|
11.6
|
13.6
|
15.6
|
19.6
|
24.6
|
29.6
|
34.5
|
39.5
|
44.5
|
49.5
|
54.4
|
59.4
|
max
|
2.2
|
2.7
|
3.2
|
4.3
|
5.3
|
6.3
|
8.3
|
10.3
|
12.4
|
14.4
|
16.4
|
20.4
|
25.4
|
30.4
|
35.5
|
40.5
|
45.5
|
50.5
|
55.6
|
60.6
|
