Machining accuracy refers to the degree of conformity between the actual value and the ideal value of the geometric parameters (size, geometry and mutual position) of the parts after machining. The deviation between the actual value and the ideal value is the machining error. The machining error reflects the machining accuracy.
THE MACHINING ACCURACY OF PARTS INCLUDES THREE ASPECTS:
Mutual position accuracy
There is a connection between these three factors.
In machining, the formation of the size, geometry and relative position between the surfaces of the parts mainly depends on the mutual position relationship between the workpiece and the tool in the process of cutting movement. The workpiece and cutter are installed on the fixture and machine tool, and are constrained by the fixture and machine tool.
In machining, machine tool, fixture, cutter and workpiece constitute a complete system, which is called process system. The problem of machining accuracy of parts is essentially the accuracy of the whole process system.
Therefore, the designer should reasonably specify the machining parts precision accuracy according to their usage. According to the design requirements and production conditions, the technologists should adopt appropriate process methods to improve the productivity and reduce the cost as much as possible on the premise of ensuring the processing accuracy.