螺丝粗螺纹攻牙钻孔径和滚造径对照表公制粗螺纹美制粗螺纹规格标准径2级牙钻孔径规格（UNC）标准径2级牙钻孔径最大最小最大最小M1.0×0.250.750.7850.729NO.1-64(1.854)1.551.5821.425M1.1×0.250.850.8850.829NO.2-56(2.184)1.801.8711.695M1.2×0.250.950.9850.985NO.3-48(2.515)2.102.1461.941M1.4×0.31.101.1421.075NO.4-40(2.845)2.302.3852.157M1.6×0.351.251.3211.221NO.5-40(3.175)2.602.6972.487M1.7×0.351.351.4211.321NO.6-32(3.505)2.802.8952.642M1.8×0.351.451.5211.421NO8-32(4.166)3.403.533.302M2.0×0.41.601.6791.567NO.10-24(4.826)3.903.9623.683M2.2×0.451.751.8381.713NO.12-24(5.486)4.504.5974.344M2.3×0.41.901.9791.8671/4-205.105.2574.979M2.5×0.452.102.1382.0135/16-186.606.7316.401M2.6×0.452.202.2382.1133/8-168.008.1537.798M3.0×0.52.502.5992.4597/16-149.409.559.144M3.0×0.62.402.4402.2801/2-1310.8011.02310.592M3.5×0.62.903.0102.8509/16-1212.2012.44611.989M4.0×0.73.303.4223.2425/8-1113.6012.86813.386M4.0×0.753.253.3263.1063/4-1016.5018.84016.307M4.5×0.753.803.8783.6887/8-919.5019.76119.177M5.0×0.84.204.3344.134122.2022.60621.971M5.0×0.94.104.1703.9301-1/8-725.0025.34924.638M6.0×1.05.005.1534.9171-1/4-728.2028.52427.813M7.0×1.06.006.1535.9171-3/8-630.8031.11530.353M8.0×1.256.806.9126.6471-1/2-634.0034.29033.528M9.0×1.257.807.9127.6471-3/4-539.5039.82738.964M10×1.58.508.6768.3762-4-1/245.2045.59344.679M11×1.59.509.6769.376　　　　M12×1.7510.3010.44110.106　　　　M14×2.012.0012.21011.835　　　　M16×2.014.0014.21013.835　　　　M18×2.515.5015.74415.294　　　　M20×2.517.5017.74417.294　　　　M22×2.519.5019.74419.294　　　　M24×3.021.0021.25220.752　　　　M27×3.024.0024.25223.752　　　　M30×3.526.5026.77126.211