The arrangement of the processing sequence should be considered according to the structure of the part and the condition of the blank, as well as the need for positioning and clamping. The important point is that the rigidity of the workpiece is not destroyed. The order should generally be carried out according to the following principles:
(1) The processing of the previous process cannot affect the positioning and clamping of the next process, and the general machine tool processing processes should also be considered comprehensively.
(2) Carry out the inner cavity processing procedure first, and then carry out the contour processing procedure.
(3) The processes of machining with the same positioning, clamping method or the same tool are better connected to reduce the number of repeated positioning, tool change times and the number of times of moving the platen.
(4) For the multiple processes carried out in the same installation, the process should first be arranged with less rigid damage to the workpiece.
Attention should be paid when determining the positioning reference and clamping plan:
(1) Strive to unify the design, process, and programming calculation benchmarks.
(2) Minimize the number of clamping times, and try to achieve all the surfaces to be processed after one positioning.
(3) Avoid using manual adjustment schemes.
(4) The fixture should be opened smoothly, and its positioning and clamping mechanism should not affect the cutting during processing (such as collision). In such a situation, use a vise or add a bottom plate to draw a screw.