常用公制螺纹钻孔底径表
M12×1.75 M12×1.5 M12×1.25 M12×1 M14×2 M14×1.5 M16×2 M16×1.5 M18×2.5 M18×1.5 M20×2.5 M20×1.5 M22×2.5 M24×3 M27×3 M30×3.5 M36×4
φ10.3 φ10.5 φ10.8 φ11 φ12 φ12.5 φ14 φ14.5 φ15.5 φ16.5 φ17.5 φ18.5 φ19.5 φ21 φ24 φ26.5 φ32
10.106~10.441 10.376~10.676 10.647~10.912 10.917~11.153 11.835~12.210 12.376~12.676 13.835~14.210 14.376~14.676 15.294~15.744 16.376~16.676 17.294~17.744 18.376~18.676 19.294~19.744 20.752~21.252 23.752~24.252 26.211~26.771 31.670~32.270
φ11.01~11.08 φ11.16~11.22 φ11.31~11.38 φ11.46~11.52 φ12.83~12.95 φ13.16~13.22 φ14.87~14.95 φ15.16~15.22 φ16.57~16.67 φ17.17~17.23 φ18.57~18.67 φ19.17~19.23
φ11.05~φ11.15 φ11.18~φ11.28 φ11.34~φ11.41 φ11.48~φ11.57 φ12.92~φ13.04 φ13.21~φ13.30 φ14.92~φ15.04 φ15.21~φ15.30 φ16.63~φ16.78 φ17.22~φ17.31 φ18.63~φ18.78 φ19.22~φ19.31
一. 切削丝锥攻牙螺纹底径简易计算公式:
外径-(牙距×0.85~0.95)=螺纹底径; 例M6×1.0
M6-(1.0×0.85)=5.15 (最大孔径)
M6-(1.0×0.95)=5.05 (最小孔径) 二. 挤牙丝锥螺纹攻牙底径简易计算公式:
外径-(牙距×0.45~0.475)=螺纹底径; 例M6×1.0
M6-(1.0×0.425)=5.575 (最大孔径)
M6-(1.0×0.475)=5.525 (最小孔径)
M42×4.5 M45×4.5 M48×5
φ37.5 φ40.5 φ43
37.129~37.799 40.129~40.799 42.587~43.297
三. 切削速度简易计算公式: 切削回转速=[(S+L)×500] D×π
例:螺纹丝攻为HSS,被切削材料为低碳钢.切削速度为S,8m/min~L,14m/min EX-SFT M6×1.0 切削速度=
(8+14)×500 = 6×3.1416
18.85
=583RPM