How to reduce the thermal deformation of CNC cutting machine
發(fā)布時間 : 2018-10-11 瀏覽次數(shù) : 13 次
In general, we talk about the thermal deformation of CNC cutting machine, many people will focus on the scale deformation of cutting materials and other issues, but CNC cutting machine itself as a hot cutting processing equipment, in the frequent use of processing, may also cause structural deformation because of temperature changes. Although as a production and processing equipment, CNC cutting machine will adopt a series of processes to minimize the impact of thermal deformation in the production process, but as a user, in the ordinary use process, or should know more about this knowledge, standardize the operation procedures, reduce the possible impact of thermal deformation.
1. Reduce fever.
The main heat source which produces thermal deformation when the machine tool is heated should be separated from the main engine as far as possible.
2. Control temperature rise.
After a series of measures to reduce heat sources, the thermal deformation will be improved. But it is usually very difficult or even impossible to completely eliminate the internal and external heat sources of machine tools. So we must control the temperature rise through good heat dissipation and cooling to reduce the influence of heat source. One of the more effective method is to force cooling in the heating part of the machine tool, but also in the low temperature part of the machine tool through heating method, so that the temperature of each point of the machine tool tends to be consistent, which can reduce the warpage caused by the temperature difference.
3. Improve machine tool organization.
Under the same heating conditions, the machine tool mechanism also has a great influence on the thermal deformation. For example, the single column mechanism used in CNC machine tools may be replaced by double column mechanism. Because of the symmetry between left and right, the deformation of the main axis of the double-column mechanism is very small except for the translation in the vertical direction, which can be easily compensated by the correction of one coordinate.
The thermal deformation of the shaft occurs in the vertical direction of the cutting tool. This can minimize the influence of the thermal deformation of the spindle on the machining diameter. In structure, the distance between the center of the spindle and the ground of the spindle should be reduced as far as possible to reduce the total amount of thermal deformation. At the same time, the temperature rise of the spindle box should be consistent with that of the spindle box, so as to avoid the tilt of the spindle after deformation.
The ball screw in the numerical control machine tool usually works under the condition of large expected load, high speed and poor heat dissipation, so the ball screw is easy to heat up. The consequence of hot production of ball screw is serious, especially in open-loop system, it will make the feed system lose positioning accuracy. At present, some machine tools use the pre drawing method to reduce the thermal deformation of the lead screw. For the thermal deformation which can not be eliminated by the above measures, the compensation pulse can be corrected according to the measurement results.
