Is it necessary to warm up the CNC machine every morning when it is turned on?

Factories without precision machining experience often blame the quality of the equipment for the unstable precision. And factories with experience in precision machining will attach great importance to the thermal balance between the ambient temperature and the machine tool. They are very clear that even high-precision machine tools can only obtain stable machining accuracy under a stable temperature environment and thermal equilibrium. Preheating the machine tool is the most basic common sense of precision machining when it is necessary to invest in high-precision machining after the machine is turned on.
1. Why should the machine tool be preheated? aluminum cnc machining part
The thermal characteristics of CNC machine tools have an important impact on the machining accuracy, accounting for more than half of the machining accuracy.
The spindle of the machine tool, the guide rails, lead screws and other components used in the XYZ motion shaft will heat up and deform due to load and friction during movement, but the thermal deformation error chain that ultimately affects the machining accuracy is the spindle and the XYZ motion shaft. The displacement of the table.
The machining accuracy of the machine tool in the state of long-term stop operation and the state of thermal equilibrium is quite different. The reason is that the temperature of the spindle and each motion axis of the CNC machine tool is relatively maintained at a certain level after running for a period of time, and With the change of processing time, the thermal accuracy of CNC machine tools tends to be stable, which indicates that it is very necessary to preheat the spindle and moving parts before processing.
However, the "warm-up exercise" of the machine tool is ignored or unknown by many factories.
2. How to preheat the machine tool?
If the machine tool is put on hold for more than a few days, it is recommended to preheat for more than 30 minutes before high-precision machining; if the machine is put on hold for only a few hours, it is recommended to preheat for 5-10 minutes before high-precision machining.
The preheating process is to let the machine tool participate in the repeated movement of the machining axis. It is best to perform multi-axis linkage. For example, let the XYZ axis move from the lower left corner of the coordinate system to the upper right corner, and repeat the diagonal line.  cnc machining part
When executing, you can write a macro program on the machine tool to let the machine tool repeatedly perform the preheating action. For example, when the CNC machine tool stops running for a long time or before processing high-precision parts, according to the mathematical 3D ellipse parameter curve and the preheated machine tool space range, t is used as the independent variable, and the coordinates of the three motion axes of XYZ are used as parameters. With a certain incremental step distance, the maximum range of the specified XYZ motion axis is used as the boundary condition of the parameter curve, and the spindle speed and the XYZ motion axis feed rate are associated with the independent variable t, so that it changes continuously within the specified range, generating The numerical control program that can be recognized by the numerical control machine tool is used to drive the motion axes of the machine tool to generate synchronous no-load motion, and is accompanied by the control transformation of the spindle speed and feed rate during the motion.
After the machine is fully warmed up, the dynamic machine can be put into high-precision machining production, and you will get stable and consistent machining accuracy.