为基孔制,过渡配合
查公差表得IT 7级为25um=0.025mm,则孔的公差为：Φ30+0.025 / -0
查轴的公差带表得K级为+2um=0.002mm
查公差表得IT 6级为16um=0.016mm
则轴的公差为：Φ30+0.018 / +0.002