EVALUATION OF PARAMETERS DETERMINING PROCESS CAPABILITIES OF MANDRELS WITH SPLIT COLLETS

Abstract

In order to fasten blanks such as rings, bushings, cups and shells, especially thin-walled ones, the use is made of a great number of devices. The previous article contained the review of the devices used and the definition of their structure with split collets, which are highly precise and wide-range, i.e. the most preferable. The devices with split collets are selected as a study object and the task was set to expand a range of diameters of blanks fixed in them while maintaining the collet strength. Developed in this article is a deformation mechanism of the split collet at its unclamping by the shaft conical section. The developed mechanism, with account of the results from the earlier performed studies on determination of the split collet strain-stress behavior, was taken as a basis for the approximated method of calculation the devices with split collets. With the use of the mentioned calculation the analysis was made of the split collet parameters which make it possible to expand a range of diameters of blanks being fixed while maintaining the collet strength. Shape and sizes of a collet belong to such parameters. While considering the variants of the coupling external profile it is necessary to be guided by the process capabilities of a simple and inexpensive method of the mentioned profile manufacture. In order to evaluate the influence of different variants of the coupling external profile shape on process capabilities of the device it is necessary to carry out the comparative calculations by the finite element method. The obtained results of the comparative calculations and their analysis are supposed to be published in the next article.