CNC precision machining process needs to pay attention to things


(1) Part clamping method and fixture selection
Nc machine tool processing is processed parts of the clamping method should also be a reasonable choice of positioning benchmark and clamping scheme, in the choice of precision benchmark, generally to follow the "unified benchmark" and "benchmark coincidence" the two principles, in addition to these two principles, we also consider:
A. Try to finish all the surface processing in one positioning clamping. Therefore, select positioning methods that are convenient for each surface to be processed.
B. When the workpiece is clamped once, it should be able to finish machining all the surfaces of the workpiece.
C. When determining the position of the workpiece on the worktable, it shall take into account the influence of the machining at all stations, the length of the tool and the rigidity of the tool on the machining quality.
D. For the jigs used in control processing, the jigs assembled by common components and adjustable should be selected as far as possible to shorten the production preparation period.
(2) Arrangement of processing sequence
When arranging the processing sequence, the basic principles must be followed, including "first surface, then hole", "first coarse and then fine", etc. In addition to these basic principles, we should also follow the following principles:
A. The cutter is processed in a centralized procedure to avoid repeated use of the same cutter and reduce the frequency and time of tool change.
B. For hole systems with high coaxiality, the processing of the hole systems at other coordinate positions should be completed after the first positioning, so as to eliminate the errors caused by repeated positioning and improve the coaxiality of the hole systems.
C. Select and determine the knife point and change the knife point, once determined, should not be replaced.