惠式螺纹（旧英制牙）山数节距换算表规格钻头径A例B例山数(25.4)节数*W18-402.652.61000.254*W532-323.253.28800.3175*w3116-243.753.77720.3518W14-205.1640.3969W516-186.65600.4233W38-1686.5560.4536W7八16-149.47.9480.5292W12-1210.79.310.5440.5773W9%16-1212.312400.635W58-1113.713.5360.7056W34-1016.716.5320.7938W7八8-919.519.3280.9071W1-822.422241.0583W18-72524.8201.27W11428.328181.4111W138-630.530.3161.5875W112633.833.5141.8143W1518-53635.7131.9538W134-539.239122.1167W118-541.841.5112.3091W2-4124544.7102.54牙套螺纹攻用92.8222规格钻头径下孔径3.175上限下限73.6286M3*0.53.13.23.1264.2333M4*0.74.24.34.175.08M5*0.85.25.335.164125.6444M6*16.36.426.2546.35M8*1.258.48.528.313127.2571M10*1.510.510.6210.373127.8154M10*1.2510.410.5210.3138.4667M10*110.310.4210.2527八88.8348M12*1.7512.512.7312.432349.2364M12*1.512.512.6212.3725189.6762M12*1.2512.512.5212.3121210.16M14*214.514.8314349M14*1.514.514.6214.37M16*216.516.8316.49M16*1.516.516.6216.37M18*2.51919.0418.58M18*1.518.518.6218.37M20*2.52121.0420.58M20*L.520.520.6220.37