1、螺螺纹纹底底孔孔直直径径 公公制制普普通通粗粗牙牙螺螺纹纹 公公制制细细牙牙螺螺纹纹 螺纹代号钻头直径螺纹代号钻头直径螺纹代号钻头直径HSS硬质合金HSS硬质合金HSS硬质合金M20.41.61.65M20.251.751.75M242.022.0M30.52.52.55M30.352.72.7M241.522.5M40.73.33.4M40.53.53.55M241.023.0M50.84.24.3M50.54.54.55M30327M61.05.05.1M60.756.36.35M30228M81.256.86.9M81.077.1M301.528.5M101.58.58.7M80.757
2、.37.35M301.529M121.7510.310.5M101.099.1M363.033.0M142.012.012.2M101.258.88.9M36234.0M162.014.014.2M100.759.39.35M361.534.5M182.515.515.7M121.510.510.7M42438M202.517.517.7M121.2510.810.9M42339M243.021.0M121.01111.1M42240M303.526.5M141.512.512.7M421.540.5M364.032.0M141.013.013.1M45441M424.537.5M161.51
3、4.514.7M45342M454.540.5M161.015.015.1M45243M485.043.0M181.516.516.7M451.543.5M181.01717.1M48444.0M202.01818.3M48345.0M201.518.518.7M48246.0M201.01919.1M481.546.5攻攻螺螺纹纹前前底底孔孔直直径径的的确确定定攻攻米米制制螺螺纹纹P P1mm1mm do=d-Pdo=d-P式式中中P-P-螺螺距距(mmmm)P P1mm1mmdo=d-do=d-(1.041.041.061.06)P Pdo-do-钻钻头头直直径径(mmmm)攻攻不不通通孔
4、孔螺螺纹纹钻钻孔孔深深度度=所所需需螺螺孔孔深深度度+0.7d+0.7dd-d-螺螺纹纹公公称称直直径径(mm)mm)(1)普通螺纹攻螺纹前底孔的钻头直径(2)非螺纹密封的管螺纹攻螺纹前钻底孔的钻头直径螺纹公称直径()1/8 1/4 3/8 1/2 3/41 1 1/41 3/81 1/2每25.4mm内牙数281919141411111111钻头直径(mm)8.811.715.218.924.430.639.241.345.1(3)英制锥管螺纹和英制锥螺纹攻丝前钻底孔的钻头直径英制锥管螺纹英制锥螺纹公称直径每25.4mm钻头直径公称直径每25.4mm钻头直径()内牙数(mm)()内牙数(mm)1/8288.4 1/8278.6 1/41911.2 1/41811.1 3/81914.7 3/81814.5 1/21418.3 1/21417.9 3/41423.6 3/41423.21 1129.71 111/229.21 1/41138.31 1/4111/237.91 1/21144.11 1/2111/243.92 1155.82 111/256