In the production of CNC lathe, precision control has an important influence on the product quality. The machining accuracy depends on the mechanical accuracy, programming accuracy, servo accuracy and error compensation value accuracy. In order to improve the machining accuracy of CNC lathe, the machining accuracy of CNC lathe can be effectively improved in the design stage through CAD design and computer simulation technology. Strengthening the maintenance of the machine in use can effectively guarantee the high precision state of the CNC lathe.
1. Analysis of machining accuracy of CNC lathe
At present, the classification of CNC lathe is mainly set precision, position precision and machining precision. Different brands of CNC lathes have different material rigidity (the quality of CNC lathe equipment), and the working temperature will have a variety of effects on the machining accuracy of CNC lathes. The geometric accuracy of CNC lathe can be further subdivided into spindle geometric accuracy and linear motion accuracy.
In the machining operation of CNC lathe, the relative position between the main shaft and the rotating shaft remains relatively fixed. In actual production and theoretical knowledge, the relative spatial position between the two shafts does not have to be relatively fixed. This is because the bearing elements that make up the spindle may have different degrees of errors in the production plant where the lathe equipment is manufactured, and will be affected by the temperature, working strength, lubrication and other conditions during the use process. Due to the bearing accuracy of the main shaft, the manual assembly quality of the main shaft box is different, the mechanical vibration of the main shaft and rotating parts in the process of processing causes the runout, the roundness of the bearing journal of the central shaft is unstable in the manufacturing process, the concentricity before and after has certain error, and the thermal deformation may occur in the working process of the main shaft. All these factors affect the spindle geometric accuracy of CNC lathe.
In addition to the geometric accuracy error caused by the spindle in CNC lathe machining, the orbit may also affect the position accuracy of the machine due to the friction and the inertia matching of the servo motor used in CNC lathe machining. Some parts of CNC lathe that need to work continuously, such as cylinder pump, motor, hydraulic machine, etc., need to work continuously for a long time (even 24 hours). In the process of working, friction causes the specific internal parts. Because of the thermal expansion and deformation of the processing heat, the actual production size of the parts deviates from the designed predetermined size. Because of the role of internal heat, the asymmetry of the components of CNC lathe equipment results in the deformation of the production and processing parts. Therefore, the thermal deformation of the components of CNC lathe equipment will have a great impact on the position accuracy of the machine The effect of the key.
The machining accuracy of CNC lathe is closely related to the geometric accuracy of the whole CNC lathe, not only to the position accuracy, but also to the transmission system failure of CNC lathe machining, the inspection of fault compensation system, the friction of machine structural parts, the position error of cutting tools, etc., as well as to whether the program editing of CNC lathe machining is correct and the production process is reasonable. Therefore, in the actual production, in order to improve the machining accuracy of CNC lathe, we must improve the geometric accuracy and position accuracy of CNC lathe machining.
