用螺纹密封的管螺纹基本牙型和基本尺寸(GB/T7306-1987) (mm)
d2=D2=d-0.640 327P d1=D1=d-1.280 654P
|
尺寸代号
|
每25.4mm
内的牙数
n
|
螺距P
|
牙高h
|
圆弧半径
r≈
|
基面上的基本直径
|
基准距离
|
有效螺
纹长度
|
装配余量
|
大径
(基准直径)
d=D
|
中径
d2=D2
|
小径
d1=D1
|
余量
|
圈数
|
1/16
|
28
|
0.907
|
0.581
|
0.125
|
7.723
|
7.142
|
6.561
|
4.0
|
6.5
|
2.5
|
|
1/8
|
28
|
0.907
|
0.581
|
0.125
|
9.728
|
9.147
|
8.566
|
4.0
|
6.5
|
2.5
|
|
1/4
|
19
|
1.337
|
0.856
|
0.184
|
13.157
|
12.301
|
11.445
|
6.0
|
9.7
|
3.7
|
|
3/8
|
19
|
1.337
|
0.856
|
0.184
|
16.662
|
15.806
|
14.950
|
6.4
|
10.1
|
3.7
|
|
1/2
|
14
|
1.814
|
1.162
|
0.249
|
20.955
|
19.793
|
18.631
|
8.2
|
13.2
|
5.0
|
|
3/4
|
14
|
1.814
|
1.162
|
0.249
|
26.441
|
25.279
|
24.117
|
9.5
|
14.5
|
5.0
|
|
1
|
11
|
2.309
|
1.479
|
0.317
|
33.249
|
31.770
|
30.291
|
10.4
|
16.8
|
6.4
|
|
|
11
|
2.309
|
1.479
|
0.317
|
41.910
|
40.431
|
38.952
|
12.7
|
19.1
|
6.4
|
|
|
11
|
2.309
|
1.479
|
0.317
|
47.803
|
46.324
|
44.845
|
12.7
|
19.1
|
6.4
|
|
2
|
11
|
2.309
|
1.479
|
0.317
|
59.614
|
58.135
|
56.656
|
15.9
|
23.4
|
7.5
|
|
|
11
|
2.309
|
1.479
|
0.317
|
75.184
|
73.705
|
72.226
|
17.5
|
26.7
|
9.2
|
4
|
3
|
11
|
2.309
|
1.479
|
0.317
|
87.884
|
86.405
|
84.926
|
20.6
|
29.8
|
9.2
|
4
|
4
|
11
|
2.309
|
1.479
|
0.317
|
113.030
|
111.551
|
110.072
|
25.4
|
35.8
|
10.4
|
|
5
|
11
|
2.309
|
1.479
|
0.317
|
138.430
|
136.951
|
135.472
|
28.6
|
40.1
|
11.5
|
5
|
6
|
11
|
2.309
|
1.479
|
0.317
|
163.830
|
162.351
|
160.872
|
28.6
|
40.1
|
11.5
|
5
|
注: 1.本表包括圆锥内螺纹与圆锥外螺纹,圆柱内螺纹与圆锥外螺纹两种联接形式。
2.本表适用于管子、管接头、旋塞、阀门和其他螺纹联接的附件。