Preheating machine improves the qualification rate of machining precision

The factory USES precision CNC machine tools (machining center, electric spark, slow moving wire, etc.) for high-precision machining. Do you have such experience that the machining precision of the first piece is often not good enough when you start the machine every morning? After a long holiday boot processing of the first parts are often very unstable accuracy, high failure probability in high-precision processing, especially the position accuracy.

Factories without experience in precision machining often attribute the instability of precision to equipment quality problems. Factories with experience in precision machining pay great attention to the thermal balance between ambient temperature and machine tools. They are well aware that even highly sophisticated machine tools can achieve stable machining accuracy only in a stable temperature environment and thermal balance. In the case of high precision machining, preheating the machine is the most basic common sense of precision machining.

Why do we need to preheat the machine?

The thermal characteristics of CNC machine tools have an important influence on the machining accuracy, accounting for almost half of the machining accuracy. The spindle of the machine tool, XYZ moving shaft parts used by the guide rail, screw and other components will be in motion due to the load and friction and deformation, but the thermal deformation error chain ultimately affects the machining accuracy of the spindle and XYZ moving shaft parts relative to the displacement of the table.

Machine for a long time to stop running state and thermal equilibrium under the condition of the machining accuracy differences, investigate its reason, because of nc machine tool spindle and the movement of the shaft after running for a period of time, the temperature relative to maintain at a constant level, and as the change of processing time, thermal steady state precision CNC machine tools, it is show the spindle and the moving parts of processing before preheating is necessary.

However, the "warm-up exercise" of machine tools is neglected or unknown by many factories.

How to preheat the machine?

If the machine is in use for more than a few days, it is recommended to preheat the machine for more than 30 minutes before high-precision machining. If the shelving state is only for a few hours, it is recommended to preheat for 5-10 minutes before high precision machining.

The process of preheating is to let the machine participate in the repeated movement of the machining axis. It is better to carry out multi-axis linkage, such as let the XYZ axis move from the lower left corner of the coordinate system to the upper right corner and repeatedly walk the diagonal.

When the execution can be written on the machine tool a macro program, let the machine repeatedly perform the action of preheating.

After the machine is fully preheated, the dynamic machine can be put into high precision machining production, and you will achieve stable and consistent machining accuracy.