COMPARATIVE STUDY OF THE PROCESS OF STITCHING OF DRILLED AND SOLID WORKPIECE

Abstract

In the process of producing seamless pipes, one of the main operations is the flashing operation on the dia-per mills. In this process, not all steel grades can be stitched into the sleeve without the appearance of defects on the inner surface. Such steel grades include corrosion-resistant and low-plastic steel grades. Hollow blanks are used for the production of pipes from such steel grades. However, the question remains open about the advisability of using hollow blanks, what diameter the hole should be, etc. In this regard, the article presents the results of computer modeling of the firmware of a drilled and solid blank, in order to conduct their comparative study. To do this, the foci of deformation of the flashing process, the stress-strain state, speed and temperature parameters were analyzed. The calculation of the plasticity resource based on the criterion of V.L. Kolmogorov for various points in the radius and length of the workpiece was carried out. It is established that the presence of a hole in the workpiece has practically no effect on the geometric parameters of the sleeve and is comparable to the geometric parameters of the sleeve obtained from a solid blank. It was revealed that the presence of a hole has a beneficial effect on the quality of the inner surface of the sleeve.