The machining center is an efficient and high-precision CNC machine tool. The workpiece can be processed in multiple processes in one clamping. At the same time, it is equipped with tool library and automatic tool change function. The rich functions of machining center determine the complexity of programming.
The machining center can realize the linkage control of three or more axes, so as to ensure the machining of complex surface. In addition to linear interpolation and circular interpolation, the machining center also has various functions, such as processing fixed cycle, automatic compensation of tool radius, automatic compensation of tool length, graphic display of machining process, man-machine dialogue, automatic fault diagnosis, off-line programming, etc.
Machining center is developed from CNC milling machine. The biggest difference between CNC milling machine and machining center is that the machining center has the ability to exchange machining tools automatically. By installing different tools on the tool magazine, the machining tools on the spindle can be changed through the automatic tool changing device in one clamping, and a variety of machining functions can be realized.
The broad meaning of benchmark is “basis”. The datum in mechanical manufacturing refers to the points, lines and surfaces used to determine the geometric relationship between the geometric elements on the production object. According to different functions and applications, datum can be divided into design datum and process datum, and process datum can be divided into process datum, positioning datum, measurement datum and assembly datum.
The technology of high-speed CNC machining is the premise to ensure the production of high-quality parts.
On lathe, the shape and size of the blank can be changed by the rotary motion of the workpiece and the linear or curvilinear motion of the cutter, and it can be processed to meet the requirements of the drawing.
Ordinary machine tools are more and more difficult to meet the needs of processing precision parts. At the same time, due to the improvement of production level, the price of CNC machine tools is falling from time to time. CNC precision parts processing mainly includes ultra precision turning, mirror grinding and grinding.
The primary premise of CNC precision parts processing is the accuracy of process datum. Datum on mechanical drawings are represented by capital letters a, B, C, D, etc. with a specific reference symbol with circle. When the reference symbol is aligned with the surface and its extension line or the dimension limit of the surface, the surface is taken as the datum. When the datum mark is aligned with the dimension line, it means that the solid center line of the dimension is taken as the datum. It is a more general statement that the process is accurate.
Assembly benchmark refers to the precision used to determine the position of parts in components or products during assembly. Measurement datum refers to the specification for the size and position of the machined surface to be measured during the inspection of parts. Positioning datum refers to the datum used for positioning the workpiece in the machine tool or fixture during machining.
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