* 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 | |||
2B① 最大 | 3B 最大 | 2B和3B① 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。 |
* 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 | |||
2B① 最大 | 3B 最大 | 2B和3B① 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。 |