What are the factors that affect the accuracy of CNC cylindrical grinding machines?


The CNC cylindrical grinder is composed of bed, worktab […]

The CNC cylindrical grinder is composed of bed, worktable, grinding wheel frame, head frame, tail frame and other parts. It is programmed in advance according to processing requirements, and the control system sends out numerical information instructions for processing. It is mainly used for grinding machines for grinding cylindrical and conical outer surfaces. Generally, it has the characteristics of generalization, high degree of modularization, high precision, high rigidity, high efficiency and high adaptability. Depending on the type, it is suitable for batch processing of related parts in industries such as automobiles, motorcycles, air compressors, bearings, military, aviation, and aerospace.
The layout of the CNC cylindrical grinder adopts the horizontal feed of the workpiece and the longitudinal reciprocating movement of the grinding wheel. The feed mechanism is arranged on the left of the operator. Due to the short stroke of the worktable, in order to facilitate and safe loading and unloading of workpieces, especially for measuring workpieces, under the control of a hydraulic control valve, the headstock can move quickly to the operator away from the grinding position. There is an interlocking relationship between this movement and the workbench. For machine tools with a grinding device installed on the top of the headbox, the end surface grinding is also performed at the position where the head moves to the operator, otherwise the end grinding device will collide with the inner wheel on the worktable when the end grinding device falls.
It is strictly forbidden for the operator to leave the grinder during the working process of the cylindrical grinder. If it is necessary to leave due to power failure or other reasons, the grinding wheel should be stopped after leaving the workpiece. When restarting, you should confirm that there are no abnormalities in all parts before driving. When working, pay attention to the status of each transmission part, such as whether the oil temperature and oil pressure are normal; whether the coolant is poured on the workpiece smoothly and accurately, whether the temperature of the rape and the motor is normal, whether there are abnormal noises, and whether the operating handles are in the correct position. Whether the fasteners are loosened and displaced.
Accuracy influencing factors:
1. The influence of the height of the grinding head, headstock and tailstock on the dimensional accuracy of the workpiece. The height error of the grinding head, headstock, and tailstock will cause the center line of the headstock and tailstock and the axis of the grinding wheel to shift in space. At this time, the surface of the workpiece will be a hyperboloid.
2. The influence of the parallelism error of the axis of the grinding head spindle in the horizontal plane by the connection between the center of the headstock and the tailstock on the dimensional accuracy of the workpiece. When this error occurs, the shape of the workpiece ground by the cylindrical grinder will be a cone, that is, the grinding wheel will be ground at an angle and the surface will have spiral grinding patterns.
3. The impact of the verticality error of the grinding head movement relative to the machine tool rail on the machining accuracy. The result of this error is that the axis of the main shaft is offset from the center of the headstock and tailstock. When grinding the end face of the shaft shoulder, it will cause an error in the perpendicularity between the end face of the shaft shoulder and the axis of the workpiece. When grinding the outer circle, it will affect the surface roughness and produce spiral grinding lines.