各种螺纹加工前的底孔尺寸

1、精选文档普通螺纹钻底孔的钻头尺寸表钻底孔钻头直径的计算公式:p1时 dTd-(1.04-1.08)p式中: p-螺距(mm) 【说明】普通螺纹代号为“M”,牙型角a为60, 一般连接 d-螺纹公称直径(mm) 多用粗牙.细牙用于薄壁零件,细牙的自锁性能较好, dT-攻螺纹前钻头直径(mm) 螺纹强度削弱少,但易滑扣. (mm)螺纹直径d螺距p螺纹内径推荐钻头直径dT螺 纹直径d螺距p螺纹内径推荐钻头直径dTMaxMinMaxMinM2粗0.41.6771.5671.6M27粗324.13223.75223.9细0.251.8091.7291.75细225.13524.83524.9M3粗0.5

2、2.5992.4592.51.525.62625.37625.5细0.352.7212.6212.65126.11825.91826.0M4粗0.73.4223.2423.3M30粗3.526.63126.21126.3细0.53.5993.4593.5细326.926.8826.7M5粗0.84.3344.1344.2228.13527.83527.9细0.54.5994.4594.51.528.62628.37628.5M6粗15.1184.9185.0129.11828.91829.0细0.755.3785.1185.2M33粗3.529.63129.21129.3M8粗1.256.88

3、76.6476.7细231.13530.83530.9细17.1186.9187.01.531.62631.37631.80.757.3787.1187.2M36粗432.1531.6731.8M10粗1.58.6268.3768.5细333.13232.75232.9细1.258.8678.6478.7234.13533.83533.919.1188.9189.01.534.62634.37634.50.759.3789.1189.2M39粗435.1534.6734.8M12粗1.7510.38610.10610.2细336.13235.75235.9细1.510.62610.37610.

4、5237.13536.83536.91.2510.86710.64710.71.537.62637.37637.5111.11810.91811.0M42粗4.537.67937.12937.3M16粗214.13513.83513.9细339.13238.75238.9细1.514.62614.37614.5240.13539.83539.9115.11814.91815.01.540.62640.37640.5M20粗2.517.63417.29417.4M45粗4.540.67940.12940.3细218.13517.83517.9细342.13241.13241.91.518.626

5、18.37618.5243.13542.83542.9119.11818.91819.01.543.62643.37643.5M24粗321.13220.75220.9M48粗543.11842.58842.7细222.13521.83521.9细345.13244.75244.81.522.62622.37622.5246.13545.83545.9123.11822.91823.01.546.62646.37646.5英寸制螺纹钻底孔的钻头尺寸表钻底孔钻头直径的计算公式:螺纹公称直径铸铁与青铜钢与黄铜3/16”5/8”dT=25(d-1/n)dT=25(d-1/n)+0.13/4”11/2

6、”dT=25(d-1/n)dT=25(d-1/n)+0.2注: dT-攻螺纹前钻头直径(mm) d-螺纹公称直径(寸) 【说明】英寸制螺纹牙型角a为55 n-每寸牙数公称直径d(寸)每寸牙数n钻头直径dT(mm)螺距P(mm)螺纹直径(mm)铸铁青铜钢黄铜大径dd中径d2小径d13/16243.73.71.0584.7624.0853.4081/4205.05.11.2706.3505.5374.7245/16186.46.51.4117.9387.0346.1313/8167.87.91.5889.5258.5097.4927/16149.19.31.81411.1129.9518.7891

7、/21210.410.52.11712.70011.3459.9895/81113.313.52.30915.87514.39712.9183/41016.316.42.54019.05017.42415.7987/8919.119.32.82222.22520.41818.6111821.922.03.17525.40023.36721.33411/8724.624.73.62928.57526.25223.92911/4727.827.93.62931.75029.42727.10411/2633.433.54.23338.10035.39032.67915/8535.735.85.080

8、41.27538.02234.77013/4538.939.05.08044.45041.19837.94517/841/241.441.55.64447.62544.01140.397241/244.644.75.64450.80047.18643.57221/4450.050.26.35057.15053.08449.01921/2456.356.56.35063.50059.43455.36923/431/261.661.87.25769.85065.20460.557331/267.968.17.25776.20071.55466.90731/431/473.673.87.81582.

9、55077.54672.54231/231/479.880.07.81588.90083.89678.89233/4385.485.68.46795.25089.82984.4094391.791.98.467101.60096.17990.759圆柱管螺纹钻底孔的钻头尺寸表【说明】非螺纹密封的圆柱管螺纹,代号为“G”,牙型角a为55.多用于压力为1.568Mpa(16kgf/cm2)以下的水,煤气管路,润滑和电线管路系统.公称直径d(寸)每寸牙数n钻头直 径dT(mm)螺距P(mm)螺纹直径(mm)大径dd中径d2小径d1G 1/8288.800.9079.7289.1478.566G 1/

10、41911.701.33713.15712.30111.445G 3/81915.2016.66215.80614.950G 1/21418.901.81420.95519.79318.631G 5/81420.8022.91121.74920.587G 3/41424.3026.44125.27924.117G 7/81428.1030.20129.03927.877G 11130.502.30933.24931.77030.291G 11/81135.2037.89736.41834.939G 11/41139.2041.91040.43138.952G 13/81141.6044.32542.84641.367G 11/21145.1047.80346.32444.845G 13/41151.0053.74652.26750.788G 21157.0059.61458.13556.656G 21/41163.0065.71064.23162.752G 21/21172.5075.18473.70572.226G 23/41178.5081.53480