What errors will occur in cnc machining?
cnc machining is the use of computer digitization and information digitization technology to control the movement and processing of machine tools. The device is a high-speed, reliable, multi-functional, intelligent and open intelligent universal pneumatic numerical control system. Cnc processing is also an important indicator to measure a country's scientific and technological development level and comprehensive national strength, as well as the modernization of information technology. It plays an immeasurable role in high-tech industries such as aviation, biology and medicine, and is a concentrated reflection of national strength. Therefore, improving the technical level is an important way to improve the comprehensive national strength and national status. So, what errors will occur in cnc machining? Let's take a look:
The principle error of cnc machining is mainly due to the approximate machining motion or tool profile. Why is it called machining principle error? It is because there are mistakes in principle. This method is feasible under the condition that the principle error does not exceed the allowable range. In the process of use, manufacturing error, installation error and wear directly affect the machining accuracy of the workpiece. These errors include the rotary motion of the machine tool spindle, the linear motion of the machine tool guide rail and the error of the machine tool transmission chain.
The manufacturing error, installation error and wear of cnc machine tools have a great impact on the machining accuracy of the workpiece. In the cutting process, the cutting edge, cutting surface, workpiece and chip have strong friction, which leads to tool wear. When the tool wear reaches a certain value, the workpiece surface roughness increases, the chip color and shape change, and accompanied by vibration. Tool wear directly affects cutting productivity, machining quality and cost. Cnc machining fixture error mainly includes positioning error, clamping error, fixture installation error and tool installation error. The error is mainly related to the machining and assembly accuracy of the fixture.
The positioning error in cnc machining mainly includes the error in the error reference and the manufacturing of the error positioning pair. When machining the workpiece, several geometric feature points on the workpiece shall be selected as the positioning reference to determine the machining position. If the selected positioning datum is inconsistent with the design datum, the datum uncorrected error will occur. The positioning surface and the fixture positioning element form a positioning pair. In the process of machining, due to the inaccurate machining of the positioning pair and the fit clearance between the positioning pairs, the position of the workpiece changes greatly, which is the machining error of the positioning pair. When using the adjustment method, the manufacturing error of the positioning pair only appears in the adjustment method, not in the trial cutting process.
