UNEF美制特細螺紋絲攻VS鑽頭下孔徑表

型號 : UNEF美制特細螺紋

○UNEF美制特細螺紋

美制特細螺紋和8UN系列及12UN系列螺紋 Unified extra fine thread & constant-pitch series with 8 & with 12 threads

標稱 Nominal size	鉆頭徑 Drill dia	2B級下孔徑 ANSI Class 2B drill hole dia	D1內螺紋內徑 ANSI Class 2B internal thread minor dia		標稱 Nominal size	鉆頭徑 Drill dia	2B級下孔徑 ANSI Class 2B drill hole dia	D1內螺紋內徑 ANSI Class 2B internal thread minor dia
標稱 Nominal size	鉆頭徑 Drill dia	2B級下孔徑 ANSI Class 2B drill hole dia	最小尺寸 Min	最大尺寸 Max	標稱 Nominal size	鉆頭徑 Drill dia	2B級下孔徑 ANSI Class 2B drill hole dia	最小尺寸 Min	最大尺寸 Max
No.12-32UNEF	4.7	4.7(90%)	4.623	4.826	1 1/4-18 UNEF	30.3	30.4(90%)	30.226	30.556
1/4-32UNEF	5.6	5.6(85%)	5.486	5.690	1 1/4-8 UN	28.5	28.7(90%)	28.321	28.956
5/16-32UNEF	7.1	7.2(85%)	7.087	7.264	1 3/8-18 UNEF	33.5	33.6(85%)	33.401	33.731
3/8-32UNEF	8.7	8.8(85%)	8.651	8.865	1 3/8-8 UN	31.8	31.8(90%)	31.496	32.131
7/16-28UNEF	10.2	10.25(85%)	10.135	10.338	1 1/2-18 UNEF	36.6	36.7(90%)	36.576	36.881
1/2-28UNEF	11.8	11.8(90%)	11.709	11.938	1 1/2-8 UN	35.0	35.0(90%)	34.671	35.306
9/16-24UNEF	13.2	13.3(85%)	13.132	13.386	1 5/8-18 UNEF	39.8	39.9(90%)	39.751	40.081
5/8-24UNEF	14.8	14.9(85%)	14.732	14.986	1 5/8-8 UN	38.2	38.2(90%)	37.846	38.481
3/4-20UNEF	17.8	17.8(90%)	17.678	17.958	1 5/8-12 UN	39.2	39.2(90%)	38.989	39.446
7/8-20UNEF	21.0	21.0(90%)	20.853	21.133	1 3/4-8 UN	41.3	41.3(90%)	41.021	41.656
1-20UNEF	24.1	24.2(85%)	24.028	24.308	1 3/4-12 UN	42.3	41.4(90%)	42.164	42.621
1 1/8-18UNEF	27.2	27.2(90%)	27.051	27.381	2-8 UN	47.8	47.8(85%)	47.371	48.006
1 1/8-8UN	25.5	25.5(90%)	25.146	25.781	2-12 UN	48.6	48.7(90%)	48.514	48.971