Precision machinery parts machining flow
Rough machining stage. Cutting off most of the machining allowances of each machining surface, and machining a fine benchmark, the main consideration is to increase productivity as much as possible.
Precision machining is a process in which the shape or performance of the workpiece is changed by machining machinery. According to the temperature state of the workpiece to be processed, it is divided into cold machining and hot machining. Generally machining at room temperature, and does not cause chemical or phase changes of the workpiece, it is called cold machining. Generally, machining at higher or lower than normal temperature will cause the chemical or phase change of the workpiece, which is called thermal machining. Cold machining can be divided into cutting machining and pressure machining according to the difference in machining methods. Thermal machining commonly includes heat treatment, forging, casting and welding.
(1) Rough machining stage. Cutting off most of the machining allowances of each machining surface, and machining a fine benchmark, the main consideration is to increase productivity as much as possible.
(2) Semi-finishing stage. Cut off the defects that may occur after rough machining, prepare for the surface finishing, require a certain machining accuracy, ensure an appropriate finishing allowance, and complete the machining of the secondary surface.
(3) Finishing stage. At this stage, a large cutting speed, small feed rate and cutting depth are used to remove the finishing allowance left by the previous process, so that the surface of the part can meet the technical requirements of the pattern.
(4) Finishing machining stage. It is mainly used to reduce the surface roughness value or strengthen the processed surface, and is mainly used for surface machining with high surface roughness requirements (ra≤0.32μm).
(5) Ultra-precision machining stage. The machining accuracy is 0.1-0.01μm, and the surface roughness value ra is less than or equal to 0.001μm in the machining stage. The main machining methods are: precision cutting, precision mirror grinding, precision grinding and polishing.