The clamping accuracy of Spring collet varies for workpieces of different diameters.
From the working principle of Spring collet, it relies on its own elastic deformation to clamp the workpiece. When the diameter of the workpiece changes, the degree of elastic deformation of the chuck will also change. For workpieces close to the nominal clamping diameter of Spring collet, the chuck can fit the workpiece surface better, and the clamping accuracy is relatively high at this time. Because in this case, the elastic deformation of the chuck is moderate, it can provide a uniform and stable clamping force, so that the workpiece can maintain good concentricity and verticality during processing.
However, when the workpiece diameter is much different from the nominal diameter of the chuck, the situation will be different. If the workpiece diameter is much smaller than the nominal diameter of the chuck, the elastic deformation of the chuck is not enough to fit the workpiece surface tightly when clamping. This may cause the workpiece to loosen or shake in the chuck, thereby affecting the clamping accuracy. For example, when performing high-precision turning, this looseness may reduce the machining accuracy of the workpiece, resulting in roundness error or cylindricity error.
On the contrary, when the workpiece diameter is larger than the nominal diameter of the chuck to a certain extent, the chuck needs to be over-deformed in order to clamp the workpiece. This may cause uneven stress distribution inside the chuck. On the one hand, it may cause excessive extrusion on the workpiece surface, leaving indentations on the workpiece surface, affecting the surface quality of the workpiece; on the other hand, uneven stress may also cause the chuck itself to deform, which may be local or overall, thereby affecting its positioning accuracy on the workpiece. For example, during milling, inaccurate positioning of the workpiece may cause deviations in the processing size.
In order to reduce the clamping accuracy problem caused by changes in workpiece diameter, some advanced Spring collets are designed with adjustable structures. By adjusting the internal structure of the chuck or the external auxiliary device, it can adapt to workpieces of different diameters within a certain range and maintain good clamping accuracy. At the same time, during use, selecting a Spring collet of appropriate specifications according to the actual diameter of the workpiece is also an important measure to ensure clamping accuracy. In addition, regular precision inspection and maintenance of the Spring collet, timely detection and repair of the problem of reduced precision caused by long-term use, also help to maintain high precision when clamping workpieces of different diameters.
