圆柱管螺纹切削前孔径 2015/9/23 作者:未知 来源:网络文摘 阅读：617 螺纹代号 每英寸牙数 钻头直径 镗孔 内径公称尺寸 G1/8 28 n 8.84 8.566 G1/4 19 11.8 11.85 11.445 G3/8 19 15.25 15.3 14.95 G1/2 14 19 19.1 18.631 G5/8 14 21 21.1 20.588 G3/4 14 24.25 24.5 24.117 G7/8 14 28.25 28.3 27.877 G1 11 30.5 30.7 30.291 G1 1/8 11 35.5 35.5 34.939 G1 1/4 11 39.5 39.5 38.952 G1 3/8 11 41.6 41.6 41.367 G1 1/2 11 45 45.2 44.845 G1 3/4 11 51 51.2 50.788 G2 11 57 57.1 56.656 G2 1/4 11 63.2 62.752 G2 1/2 11 72.6 72.226 G3 11 85.4 84.926 G4 11 110.5 110.072 G5 11 136 135.472 G6 11 161.4 160.872
