タップ下穴表 【技術資料】

一般タップ用　ねじ下穴径表

ISOメートル並目ねじ (一般的に最も広く使用)

呼び	下穴径(mm)	最小寸法(mm)	最大寸法(mm)
M1×0.25	0.75	0.729	0.785
M1.1×0.25	0.85	0.829	0.885
M1.2×0.25	0.95	0.929	0.985
M1.4×0.3	1.10	1.075	1.142
M1.6×0.35	1.25	1.221	1.321
M1.8×0.35	1.45	1.421	1.521
M2×0.4	1.60	1.567	1.679
M2.2×0.45	1.75	1.713	1.838
M2.5×0.45	2.05	2.013	2.138
M3×0.5	2.50	2.459	2.599
M3.5×0.6	2.90	2.850	3.010
M4×0.7	3.30	3.242	3.422
M4.5×0.75	3.70	3.688	3.878
M5×0.8	4.20	4.134	4.334
M6×1	5.00	4.917	5.153
M7×1	6.00	5.917	6.153
M8×1.25	6.80	6.647	6.912
M9×1.25	7.80	7.647	7.912
M10×1.5	8.50	8.376	8.676
M11×1.5	9.50	9.376	9.676
M12×1.75	10.20	10.106	10.441
M14×2	12.00	11.835	12.210
M16×2	14.00	13.835	14.210
M18×2.5	15.50	15.294	15.744
M20×2.5	17.50	17.294	17.744
M22×2.5	19.50	19.294	19.744
M24×3	21.00	20.752	21.252
M27×3	24.00	23.752	24.252
M30×3.5	26.50	26.211	26.771
M33×3.5	29.50	29.211	29.771
M36×4	32.00	31.670	32.270
M39×4	35.00	34.670	35.270
M42×4.5	37.50	37.129	37.799
M45×4.5	40.50	40.129	40.799
M48×5	43.00	42.587	43.297
M52×5	47.00	46.587	47.297
M56×5.5	50.50	50.046	50.796

ISOメートル細目ねじ

呼び	下穴径(mm)	最小寸法(mm)	最大寸法(mm)
M2.5×0.35	2.15	2.121	2.221
M3×0.35	2.65	2.621	2.721
M3.5×0.35	3.15	3.121	3.221
M4×0.5	3.50	3.459	3.599
M4.5×0.5	4.00	3.959	4.099
M5×0.5	4.50	4.459	4.599
M5.5×0.5	5.00	4.959	5.099
M6×0.75	5.20	5.188	5.378
M7×0.75	6.20	6.188	6.378
M8×0.75	7.20	7.188	7.378
M8×1	7.00	6.917	7.153
M9×0.75	8.20	8.188	8.378
M9×1	8.00	7.917	8.153
M10×0.75	9.20	9.188	9.378
M10×1	9.00	8.917	9.153
M10×1.25	8.80	8.647	8.912
M11×0.75	10.20	10.188	10.378
M11×1	10.00	9.917	10.153
M12×1	11.00	10.917	11.153
M12×1.25	10.80	10.647	10.912
M12×1.5	10.50	10.376	10.676
M14×1	13.00	12.917	13.153
M14×1.25	12.80	12.647	12.912
M14×1.5	12.50	12.376	12.676
M15×1	14.00	13.917	14.153
M15×1.5	13.50	13.376	13.676
M16×1	15.00	14.917	15.153
M16×1.5	14.50	14.376	14.676
M17×1	16.00	15.917	16.153
M17×1.5	15.50	15.376	15.676
M18×1	17.00	16.917	17.153
M18×1.5	16.50	16.376	16.676
M18×2	16.00	15.835	16.210
M20×1	19.00	18.917	19.153
M20×1.5	18.50	18.376	18.676
M20×2	18.00	17.835	18.210
M22×1	21.00	20.917	21.153
M22×1.5	20.50	20.376	20.676
M22×2	20.00	19.835	20.210
M24×1	23.00	22.917	23.153
M24×1.5	22.50	22.376	22.676
M24×2	22.00	21.835	22.210
M25×1	24.00	23.917	24.153
M25×1.5	23.50	23.376	23.676
M25×2	23.00	23.835	23.210
M27×1	26.00	25.917	26.153
M27×1.5	25.50	25.376	25.676
M27×2	25.00	24.835	25.210
M28×1	27.00	26.917	27.153
M28×1.5	26.50	26.376	26.676
M28×2	26.00	25.835	26.210
M30×1	29.00	28.917	29.153
M30×1.5	28.50	28.376	28.676
M30×2	28.00	27.835	28.210
M30×3	27.00	26.752	27.252
M32×1.5	30.50	30.376	30.676
M32×2	30.00	29.835	30.210
M33×1.5	31.50	31.376	31.676
M33×2	31.00	30.835	31.210
M33×3	30.00	29.752	30.252
M35×1.5	33.50	33.376	33.676
M36×1.5	34.50	34.376	34.676

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ユニファイ並目ねじ

呼び	下穴径(mm)	最小寸法(mm)	最大寸法(mm)
No.1 -64	1.55	1.425	1.580
No.2 -56	1.85	1.694	1.872
No.3 -48	2.10	1.941	2.146
No.4 -40	2.35	2.157	2.385
No.5 -40	2.65	2.487	2.698
No.6 -32	2.85	2.642	2.896
No.8 -32	3.50	3.302	3.531
No.10 -24	3.90	3.683	3.937
No.12 -24	4.50	4.343	4.597
1/4 -20	5.10	4.978	5.258
5/16 -18	6.60	6.401	6.731
3/8 -16	8.00	7.798	8.153
7/16 -14	9.40	9.144	9.550
1/2 -13	10.80	10.592	11.024
9/16 -12	12.20	11.989	12.446
5/8 -11	13.50	13.386	13.868
3/4 -10	16.50	16.307	16.840
7/8 -9	19.50	19.177	19.761
1 -8	22.25	21.971	22.606
1 1/8 -7	25.00	24.638	25.349
1 1/4 -7	28.00	27.813	28.524
1 3/8 -6	30.75	30.353	31.115
1 1/2 -6	34.00	33.528	34.290
1 3/4 -5	39.50	38.938	39.802
2 -4.5	45.00	44.679	45.593

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転造タップ用　ねじ下穴径表

ISOメートル並目ねじ (一般的に最も広く使用)

呼び	下穴径(mm)
M1×0.25	0.90
M1.1×0.25	1.00
M1.2×0.25	1.10
M1.4×0.3	1.28
M1.6×0.35	1.46
M1.7×0.35	1.56
M1.8×0.35	1.66
M2×0.4	1.85
M2.2×0.45	2.00
M2.3×0.4	2.11
M2.5×0.45	2.30
M2.6×0.45	2.40
M3×0.5	2.80
M3.5×0.6	3.25
M4×0.7	3.70
M4.5×0.75	4.20
M5×0.8	4.65
M6×1	5.55
M7×1	6.55
M8×1.25	7.40
M9×1.25	8.40
M10×1.5	9.30
M11×1.5	10.30
M12×1.75	11.20
M14×2	13.10
M16×2	15.10
M18×2.5	16.90
M20×2.5	18.90

ISOメートル細目ねじ

呼び	下穴径(mm)
M5×0.5	4.80
M5.5×0.5	5.30
M6×0.75	5.65
M7×0.75	6.65
M8×0.75	7.65
M8×1	7.55
M9×0.75	8.65
M9×1	8.55
M10×0.75	9.65
M10×1	9.55
M10×1.25	9.40
M11×0.75	10.65
M11×1	10.55
M12×1	11.55
M12×1.25	11.40
M12×1.5	11.30
M14×1	13.55
M14×1.25	13.40
M14×1.5	13.30
M15×1	14.55
M15×1.5	14.30
M16×1	15.55
M16×1.5	15.30
M17×1	16.55
M17×1.5	16.30
M18×1	17.55
M18×1.5	17.30
M18×2	17.10
M20×1	19.55