丝锥攻螺纹选用钻头及尺寸螺纹内径螺纹公称直径（d）螺距（P）最大最小推荐钻头直径（d0）备 注粗0.84.3344.1344.20M5 细0.54.5994.4594.50粗15.1184.9185.00M6 细0.755.3785.1185.20M20×2粗1.256.8876.6476.70M8细10.757.1187.3786.9187.1187.007.20M24×2粗1.58.6268.3768.50M10细1.2510.758.8679.1189.3788.6478.9189.1188.709.009.20粗1.7510.38610.10610.20M12细1.51.25110.62610.86711.11810.37610.64710.91810.5010.7011.00粗214.13513.83513.90M16细1.51.014.62615.11814.37614.91814.5015.00粗2.517.63417.29417.40M20细21.5118.13518.62619.11817.83518.37618.91817.9018.5019.00丝锥攻螺纹选用钻头及尺寸螺纹内径螺纹公称直径（d）螺距（P）最大最小推荐钻头直径（d0）M5粗0.84.3344.1344.20M6粗15.1184.9185.00M8粗1.256.8876.6476.70M10粗1.58.6268.3768.50M12粗1.7510.38610.10610.20M16粗214.13513.83514.00M20粗2.517.63417.29417.50。