螺纹底孔直径表

公制普通粗牙螺纹

钻头直径螺纹代号HSS硬质合金M2×0.41.61.65M3×0.52.52.55M4×0.73.33.4M5×0.84.24.3M6×1.05.05.1M8×1.256.86.9M10×1.58.58.7M12×1.7510.310.5M14×2.012.012.2M16×2.014.014.2M18×2.515.515.7M20×2.517.517.7M24×3.021.0……M30×3.526.5……M36×4.032.0……M42×4.537.5……M45×4.540.5……M48×5.043.0……螺纹代号M2×0.2M3×0.3M4×0.M5×0.M6×0.7M8×1.M8×0.7M10×1M10×1.M10×0.M12×1M12×1.M12×1M14×1M14×1M16×1M16×1M18×1M18×1M20×2M20×1M20×1M24×2M24×1M24×1M30×M30×M30×1M30×1M36×3M36×M36×1M42×M42×M42×M42×1M45×M45×M45×M45×1M48×M48×M48×M48×1

攻螺纹前底孔直径的确定

（1）普通螺纹攻螺纹前底孔的钻头直

（2）非螺纹密封的管螺纹攻螺纹前钻底孔的

螺纹公称直径（\"）每25.4mm内牙数钻头直径（mm） 1/8288.8 1/41911.7 3/8 1/21418.9 3/41915.21424.4（3）英制锥管螺纹和英制锥螺纹攻丝前钻底孔

英制锥管螺纹英制锥螺纹公称直径（\"） 1/8 1/4 3/8每25.4mm内牙数281919141411111111钻头直径（mm）8.411.214.718.323.629.738.344.155.8公称直径（\"） 1/8 1/4 3/8每25.4mm内牙数2718181414111/2111/2111/2111/2钻头直径（mm）8.611.114.517.923.229.237.943.956 1/2 3/4 1/2 3/411 1/41 1/2211 1/41 1/22公制细牙螺纹

纹代号2×0.253×0.354×0.55×0.56×0.758×1.08×0.7510×1.00×1.250×0.7512×1.52×1.2512×1.014×1.514×1.016×1.516×1.018×1.518×1.020×2.020×1.520×1.024×2.024×1.524×1.0M30×3钻头直径HSS1.752.73.54.56.377.398.89.310.510.81112.513.014.515.016.5171818.51922.022.523.027硬质合金1.752.73.554.556.357.17.359.18.99.3510.710.911.112.713.114.715.116.717.118.318.719.1……………………M30×230×1.530×1.536×3.0M36×236×1.5M42×4M42×3M42×242×1.5M45×4M45×3M45×245×1.5M48×4M48×3M48×248×1.52828.52933.034.034.538394040.541424343.544.045.046.046.5………………………………………………………………………………………………的确定

钻头直径

底孔的钻头直径

11130.61 1/41139.21 3/81141.31 1/21145.1钻底孔的钻头直径