High speed CNC machining can change the shape and size of products, which plays a very important role.
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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