GB /T 20330 - 2006 攻丝前钻孔用麻花钻直径

用于普通螺纹（按GB/T 193-2003) 的麻花钻直径 —— 粗牙系列

螺纹						麻花钻直径 mm
公称直径	螺距	下列等级的小径 (mm)
公称直径	螺距	5H 最大	6H 最大	7H 最大	5H、6H、7H 最小
1	0.25	0.785	/	/	0.729	0.75
1.1	0.25	0.885	/	/	0.829	0.85
1.2	0.25	0.985	/	/	0.929	0.95
1.4	0.3	1.142	1.16	/	1.075	1.1
1.6	0.35	1.301	1.321	/	1.221	1.25
1.8	0.35	1.501	1.521	/	1.421	1.45
2	0.4	1.657	1.679	/	1.567	1.6
2.2	0.45	1.813	1.838	/	1.713	1.75
2.5	0.45	2.113	2.138	/	2.013	2.05
3	0.5	2.571	2.599	2.639	2.459	2.5
3.5	0.6	2.975	3.01	3.05	2.85	2.9
4	0.7	3.382	3.422	3.466	3.242	3.3
4.5	0.75	3.838	3.878	3.924	3.688	3.7
5	0.8	4.294	4.334	4.384	4.134	4.2
6	1	5.107	5.153	5.217	4.917	5
7	1	6.107	6.153	6.217	5.917	6
8	1.25	6.859	6.912	6.982	6.647	6.8
9	1.25	7.859	7.912	7.982	7.647	7.8
10	1.5	8.612	8.676	8.751	8.376	8.5
11	1.5	9.612	9.676	9.751	9.376	9.5
12	1.75	10.371	10.441	10.531	10.106	10.2
14	2	12.135	12.21	12.31	11.835	12
16	2	14.135	14.21	14.31	13.835	14
18	2.5	15.649	15.744	15.854	15.294	15.5
20	2.5	17.649	17.744	17.854	17.294	17.5
22	2.5	19.649	19.744	19.854	19.294	19.5
24	3	21.152	21.252	21.382	20.752	21
27	3	24.152	24.252	24.382	23.752	24
30	3.5	26.661	26.771	26.921	26.211	26.5
33	3.5	29.661	29.771	29.921	29.211	29.5
36	4	32.145	32.27	32.42	31.67	32
39	4	35.145	35.27	35.42	34.67	35
42	4.5	37.659	37.779	37.979	37.129	37.5
45	4.5	40.659	40.779	40.979	40.129	40.5
48	5	43.147	43.297	43.487	42.587	43
52	5	47.147	47.297	47.487	46.587	47
56	5.5	50.646	50.796	50.996	50.046	50.5

用于普通螺纹（按GB/T 193-2003) 的麻花钻直径 —— 细牙系列

螺纹						麻花钻直径 mm
公称直径	螺距	下列等级的小径 (mm)
公称直径	螺距	5H 最大	6H 最大	7H 最大	5H、6H、7H 最小
2.5	0.35	2.201	2.221	/	2.121	2.15
3	0.35	2.701	2.721	/	2.621	2.65
3.5	0.35	3.201	3.221	/	3.121	3.15
4	0.5	3.571	3.599	3.639	3.459	3.5
4.5	0.5	4.071	4.099	4.139	3.959	4
5	0.5	4.571	4.599	4.639	4.459	4.5
5.5	0.5	5.071	5.099	5.139	4.959	5
6	0.75	5.338	5.378	5.424	5.188	5.2
7	0.75	6.338	6.378	6.424	6.188	6.2
8	0.75	7.338	7.378	7.424	7.188	7.2
9	0.75	8.338	8.378	8.424	8.188	8.2
10	0.75	9.338	9.378	9.424	9.188	9.2
11	0.75	10.338	10.378	10.424	10.188	10.2
8	1	7.107	7.153	7.217	6.917	7
9	1	8.107	8.153	8.217	7.917	8
10	1	9.107	9.153	9.217	8.917	9
11	1	10.107	10.153	10.217	9.917	10
12	1	11.107	11.153	11.217	10.917	11
14	1	13.107	13.153	13.217	12.917	13
15	1	14.107	14.153	14.217	13.917	14
16	1	15.107	15.153	15.217	14.917	15
17	1	16.107	16.153	16.217	15.917	16
18	1	17.107	17.153	17.217	16.917	17
20	1	19.107	19.153	19.217	18.917	19
22	1	21.107	21.153	21.217	20.917	21
24	1	23.107	23.153	23.217	22.917	23
25	1	24.107	24.153	24.217	23.917	24
27	1	26.107	26.153	26.217	25.917	26
28	1	27.107	27.153	27.217	26.917	27
30	1	29.107	29.153	29.217	28.917	29
10	1.25	8.859	8.912	8.982	8.647	8.8
12	1.25	10.859	10.912	10.982	10.647	10.8
14	1.25	12.859	12.912	12.982	12.647	12.8
12	1.5	10.612	10.676	10.751	10.376	10.5
14	1.5	12.612	12.676	12.751	12.376	12.5
15	1.5	13.612	13.676	13.751	13.376	13.5
16	1.5	14.612	14.676	14.751	14.376	14.5
17	1.5	15.612	15.676	15.751	15.376	15.5
18	1.5	16.612	16.676	16.751	16.376	16.5
20	1.5	18.612	18.676	18.751	18.376	18.5
22	1.5	20.612	20.676	20.751	20.376	20.5
24	1.5	22.612	22.676	22.751	22.376	22.5
25	1.5	23.612	23.676	23.751	23.376	23.5
26	1.5	24.612	24.676	24.751	24.376	24.5
27	1.5	25.612	25.676	25.751	25.376	25.5
28	1.5	26.612	26.676	26.751	26.376	26.5
30	1.5	28.612	28.676	28.751	28.376	28.5
32	1.5	30.612	30.676	30.751	30.376	30.5
33	1.5	31.612	31.676	31.751	31.376	31.5
35	1.5	33.612	33.676	33.751	33.376	33.5
36	1.5	34.612	34.676	34.751	34.376	34.5
38	1.5	35.612	36.676	36.751	36.376	36.5
39	1.5	37.612	37.676	37.751	37.376	37.5
40	1.5	38.612	38.676	38.751	38.376	38.5
42	1.5	40.612	40.676	40.751	40.376	40.5
45	1.5	43.612	43.676	43.751	43.376	43.5
48	1.5	46.612	46.676	46.751	46.376	46.5
50	1.5	48.612	48.676	48.751	48.376	48.5
52	1.5	50.612	50.676	50.751	50.376	50.5
18	2	16.135	16.21	16.31	15.835	16
20	2	18.135	18.21	18.31	17.835	18
22	2	20.135	20.21	20.31	19.835	20
24	2	22.135	22.21	22.31	21.835	22
25	2	23.135	23.21	23.31	22.835	23
27	2	25.135	25.21	25.31	24.835	25
28	2	26.135	26.21	26.31	25.835	26
30	2	28.135	28.21	28.31	27.835	28
32	2	30.135	30.21	30.31	29.835	30
33	2	31.135	31.21	31.31	30.835	31
36	2	34.135	34.21	34.31	33.835	34
39	2	37.135	37.21	37.31	36.835	37
40	2	38.135	38.21	38.31	37.835	38
42	2	40.135	40.21	40.31	39.835	40
45	2	43.135	43.21	43.31	42.835	43
48	2	46.135	46.21	46.31	45.835	46
50	2	48.135	48.21	48.31	47.835	48
52	2	50.135	50.21	50.31	49.835	50
30	3	27.152	27.252	27.382	26.752	27
33	3	30.152	30.252	30.382	29.752	30
36	3	33.152	33.252	33.382	32.752	33
39	3	36.152	36.252	36.382	35.752	36
40	3	37.152	37.252	37.382	36.752	37
42	3	39.152	39.252	39.382	38.752	39
45	3	42.152	42.252	42.382	41.752	42
48	3	45.152	46.252	45.382	44.752	45
50	3	47.152	47.252	47.382	46.752	47
52	3	49.152	49.252	49.382	48.752	49
42	4	38.145	38.27	38.42	37.67	38
45	4	41.145	41.27	41.42	40.67	41
48	4	44.145	44.27	44.42	43.67	44
52	4	48.145	48.27	48.42	47.67	48

用于英制螺纹（按ISO 263-1973）的麻花钻直径 —— 统一制粗牙螺纹（UNC）

* 除另有说明外尺寸单位都以毫米计
螺纹						麻花钻直径
公称直径 in	每吋牙数	螺距	下列等级的小径
公称直径 in	每吋牙数	螺距	2B^① 最大	3B 最大	2B和3B^① 最小
NO.1	64	0.397	1.582	1.582	1.425	1.55
NO.2	56	0.454	1.872	1.872	1.694	1.85
NO.3	48	0.529	2.146	2.146	1.941	2.1
NO.4	40	0.635	2.385	2.385	2.156	2.35
NO.5	40	0.635	2.697	2.697	2.487	2.65
NO.6	32	0.794	2.896	2.896	2.642	2.85
NO.8	32	0.794	3.531	3.528	3.302	3.5
NO.1O	24	1.058	3.962	3.95	3.683	3.9
NO.12	24	1.058	4.597	4.95	4.343	4.5
1/4	20	1.27	5.268	5.25	4.976	5.1
5/16	18	1.411	6.734	6.68	6.411	6.6
3/8	16	1.588	8.164	8.082	7.805	8
7/16	14	1.814	9.55	9.441	9.149	9.4
1/2	13	1.954	11.013	10.881	10.584	10.8
9/16	12	2.117	12.456	12.301	11.996	12.2
5/8	11	2.309	13.868	13.693	13.376	13.5
3/4	10	2.54	16.833	16.624	16.299	16.5
7/8	9	2.822	19.748	19.52	19.169	19.5
1	8	3.175	22.598	22.344	21.963	22.25
1-1/8	7	3.629	25.349	25.082	24.648	25
1-1/4	7	3.629	28.524	28.258	27.832	28
1-3/8	6	4.233	31.12	30.851	30.343	30.75
1-1/2	6	4.233	34.295	34.026	33.518	34
1-3/4	5	5.08	39.814	39.56	38.951	39.5
2	4-1/2	5.644	45.598	45.367	44.689	45
① 对分数直径包括1级。

用于英制螺纹（按ISO 263-1973）的麻花钻直径 —— 统一制细牙螺纹（UNF）

* 除另有说明外尺寸单位都以毫米计
螺纹						麻花钻直径
公称直径 in	每吋牙数	螺距	下列等级的小径
公称直径 in	每吋牙数	螺距	2B^① 最大	3B 最大	2B和3B^① 最小
NO.0	80	0.318	1.306	1.306	1.181	1.25
NO.1	72	0.353	1.613	1.613	1.473	1.55
NO.2	64	0.397	1.913	1.913	1.755	1.9
NO.3	56	0.454	2.197	2.197	2.024	2.15
NO.4	48	0.529	2.459	2.456	2.271	2.4
NO.5	44	0.577	2.741	2.741	2.55	2.7
NO.6	40	0.635	3.023	3.012	2.819	2.95
NO.8	36	0.706	3.607	3.597	3.404	3.5
NO.1O	32	0.794	4.166	4.168	3.962	4.1
NO.12	28	0.907	4.724	4.717	4.496	4.7
1/4	28	0.907	5.58	5.563	5.367	5.5
5/16	24	1.058	7.038	6.995	6.792	6.9
3/8	24	1.058	8.626	8.565	8.379	8.5
7/16	20	1.27	10.03	9.947	9.738	9.9
1/2	20	1.27	11.618	11.524	11.326	11.5
9/16	18	1.411	13.084	12.969	12.761	12.9
5/8	18	1.411	14.671	14.554	14.348	14.5
3/4	16	1.588	17.689	17.546	17.33	17.5
7/8	14	1.814	20.663	20.493	20.262	20.4
1	12	2.117	23.569	23.363	23.109	23.25
1-1/8	12	2.117	26.744	26.538	26.284	26.5
1-1/4	12	2.117	29.919	29.713	29.459	29.5
1-3/8	12	2.117	33.094	32.888	32.634	32.75
1-1/2	12	2.117	36.269	36.063	35.809	36
① 对分数直径包括1级。

用于不以螺纹作压力密封联接的场合（按GB/T 7307-2001）

* 除另有说明外尺寸单位都以毫米计
螺纹					麻花钻直径
公称直径 in	每吋牙数	螺距	小径
公称直径 in	每吋牙数	螺距	最大	最小
1/16	28	0.907	6.843	6.561	6.8^①
1/8	28	0.907	8.848	8.566	8.8
1/4	19	1.337	11.89	11.445	11.8
3/8	19	1.337	16.395	14.95	15.25
1/2	14	1.814	19.172	18.631	19
5/8	14	1.814	21.128	20.587	21
3/4	14	1.814	24.658	24.117	24.5
7/8	14	1.814	28.418	27.877	28.25
1	11	2.309	30.931	30.291	30.75
1-1/8	11	2.309	35.579	34.939	35.5^①
1-1/4	11	2.309	39.592	38.952	39.5
1-1/2	11	2.309	45.485	44.845	45
1-3/4	11	2.309	51.428	50.788	51
2	11	2.309	57.296	56.656	57
① 该数值近似于螺纹大径-螺距。

用于以螺纹作压力密封联接的场合（按GB/T 7306.1-2000）

* 除另有说明外尺寸单位都以毫米计
螺纹					麻花钻直径
公称直径 in	每吋牙数	螺距	小径
公称直径 in	每吋牙数	螺距	最大	最小
1/16	28	0.907	6.632	6.49	6.6^①
1/8	28	0.907	8.637	8.495	8.6
1/4	19	1.337	11.549	11.341	11.5
3/8	19	1.337	15.054	14.846	15
1/2	14	1.814	18.773	18.489	18.5
3/4	14	1.814	24.259	23.975	24
1	11	2.309	30.471	30.111	30.25
1-1/4	11	2.309	39.132	38.772	39
1-1/2	11	2.309	45.025	44.665	45
2	11	2.309	56.836	56.476	56.5
① 该数来源于 BSI 1157-75。