Classification and positioning benchmarks for large-scale machining

Large-scale machining is mainly composed of several surfaces in the process of making. To study the relative relationship of the surface of the parts, a datum must be determined. The datum is the point on the part used to determine the position of other points, lines, and surfaces. Line surface. According to the different functions of benchmarks, benchmarks can be divided into design benchmarks and process benchmarks.
Classification of large-scale machining
Design datum for large-scale machining: the datum used to determine other points, lines, surfaces and positions on the part drawing is called the design datum. The process datum: the datum used in the processing and assembly of the part. Called process benchmark. Process benchmarks are divided into assembly benchmarks, measurement benchmarks and positioning benchmarks according to different uses.
Assembly datum for large-scale machining: the datum used to determine the position of the part in the component or product during assembly is called the assembly datum.
Measurement datum for large-scale machining: the datum used to inspect the size and position of the machined surface is called the measurement datum.
The positioning datum of large-scale machining: the datum used for positioning the workpiece during processing is called the positioning datum. The surface (or line, point) used as the positioning reference can only be selected from the unprocessed surface of the blank in the process. This positioning surface is called the rough reference. In the subsequent processes, the processed surface can be used as the positioning reference. This kind of positioning surface is called a fine datum.
Precise and ultra-precision machining is an important part of modern machining and manufacturing technology. When used, it is mainly one of the important indicators to measure the level of a high-tech manufacturing industry. With the development of computer and information technology Development has put forward higher requirements on manufacturing technology, not only requiring extremely high size and shape and position accuracy, but also requiring extremely high surface quality. It is precisely under this market demand that ultra-precision processing technology has been rapidly developed, and various processes and new methods have been emerging.