螺纹规格及攻丝底孔对照表螺纹规格钻头直径Φ1.25M2X0.4Φ1.6Φ2.05M3X0.5Φ2.5Φ2.9M4X0.7Φ3.3M5X0.8Φ4.2M6X1Φ5M8X1.25Φ6.8M8X1Φ7M10X1.5Φ8.5M10X1.25Φ8.8M12X1.75Φ10.2M12X1.50Φ10.5M12X1.25Φ10.8M14X2Φ12M14X1.5Φ12.5M16X2Φ14M16X1.5Φ14.5M18X2.5Φ15.5M18X1.5Φ16.5M20X2.5Φ17.5M20X1.5Φ18.5M22X2.5Φ19.5M22X1.5Φ20.5M24X3Φ21M24X2Φ22M27X3Φ24M27X2Φ25M30X3.5Φ26.5M33X3.5Φ29.3M36X4Φ31.8M39X4Φ34.8M42X4.5Φ37.3螺纹底孔直径公制粗牙螺纹螺纹代号钻头直径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……细牙螺纹螺纹代号钻头直径铝硬质合金M2×0.251.751.75M3×0.352.72.7M4×0.53.53.55M5×0.54.54.55M6×0.756.36.35M8×1.077.1M8×0.757.37.35M10×1.099.1M10×1.258.88.9M10×0.759.39.35M12×1.510.510.7M12×1.2510.810.9M12×1.01111.1M14×1.512.512.7M14×1.013.013.1M16×1.514.514.7M16×1.015.015.1M18×1.516.516.7M18×1.01717.1M20×2.01818.3M20×1.518.518.7M20×1.01919.1M24×2.022.0M24×1.522.5M24×1.023.0M30×327M30×228M30×1.528.5M30×1.529M36×3.033.0M36×234.0M36×1.534.5M42×438M42×339M42×240M42×1.540.5M45×441M45×342M45×243M45×1.543.5螺纹粗牙细牙M10.250.2M1.10.250.2M1.60.350.2M20.40.25M2.50.450.35M30.50.35M40.70.5M50.80.5M610.75,(0.5)M81.251,0.75,(0.5)M101.51.25,1,0.75,(0.5)M121.751.5,1.25,1,(0.75),(0.5)(M14)21.5,1.25,1,(0.75),(0.5)M1621.5,1.25,1,(0.75),(0.5)(M18)2.52,1.5,1.25,1,(0.75),(0.5)M202.52,1.5,1.25,1,(0.75),(0.5)(M22)2.52,1.5,1.25,1,(0.75),(0.5)M2432,1.5,1,(0.75)(M27)32,1.5,1,(0.75)M303.53,2,1.5,1,(0.75)(M33)3.5(3),2,1.5,1,(0.75)M3643,2,1.5,(1)(M39)43,2,1.5,(1)M424.5(4),3,2,1.5,(1)(M45)4.5(4),3,2,1.5,(1)M485(4),3,2,1.5,(1)(M52)5(4),3,2,1.5,(1)M565.54,3,2,1.5,(1)(M60)5.54,3,2,1.5,(1)M6464,3,2,1.5,(1)(M68)64,3,2,1.5,(1)M7264,3,2,1.5,(1)(M76)64,3,2,1.5,(1)M8064,3,2,1.5,(1)螺纹螺距（粗牙、细牙）对照表