螺丝头部标准 盘头螺钉(代码:P) JIS B1111 Pan head screws unit:mm螺纹公称直径d螺距P十字槽槽号dkKrf1rf2mq(1)rdaE(2)F(2)G基本尺寸偏差基本尺寸偏差约约参考maxminminmaxmaxmaxmaxM20.413.5-0.41.30.14.50.62.21.010.60.12.60.150.12(M2.2)0.4541.550.72.41.210.80.12.80.20.15M2.50.454.51.760.82.61.4210.13.10.20.15