Some key words related with reference datum （基准,Reference datum (基准） Design reference (设计基准） Process reference (工艺基准） Location element (定位元件) Location datum(定位基准) Datum Superposition (基准重合) Non-superposition (不重合) Operational datum (工序基准) Operational draft (工序图,reference,Design reference,Process reference,Defined as those points, lines or surfaces which act as references to determine other Points,lines or surfaces,The reference in design drawing,Used to locate the position of the workpiece in ma
