The technology of the shell case rolling into the rough pipe on an automatic mill of the pipe-rolling plant PRP 220 was considered. In case of the pipe rear end stability losing for a special thin-walled assortment of rolling products the theoretical research was carried out based on the FEM. As the result of the research the nature of such flaw as a “fin” on the end of the pipe was investigated, the evaluation of the loading on the automatic mill for the PRP 220 was obtained for different process parameters.

Deformation of shafts and seamless tubes are carried out by a radial forging machine in order to achieve the required dimensions and improve the mechanical parameters of the material. Hence, the study of improving the performance of the radial machine leads to an increase in the quality of the forged tube, while the machine equipment in the process of radial forging will have the least erosion. In this process, the workpiece is surrounded by four tools and during the repeated blows of the die, the desired dimensions of the workpiece are obtained. with regards to the contact surface of the die with the workpiece, the most common tool that faces the highest erosion is the die. Therefore, the improvement of die geometry in order to minimize wear has been investigated in this article. Also, the distribution of die temperature and analysis of die stress during the process has been implemented. Accordingly, three types of die geometries: Flat, Concave and Convex are considered to measure the depth of wear and determine the maximum erosion through 3D finite element simulation and experimental estimates. Therefore, according to the comparison between numerical and analytical results in the case of wear analysis with experimental results, the validation of simulation was confirmed.

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The article addresses to distribution of loading between working and backup rolls of sheet levelling machines taking into account presence of initial gaps between them and heating that occurs during the straightening process, which is especially important in case of the high-temperature straightening. For levelling machines with a single row of backup rolls calculated dependencies were obtained to evaluate loads suffered by backup roll taking into account factors under this study and the analysis of results for the 9-roll straightening machine were carried out. The analysis showed a significant overload suffered by backup rolls.

This experimental study was conducted on the equipment of pipe-rolling plant-140 with an automatic mill in order to give a qualitative and quantitative evaluation of the parameters which define the pipe wall sizing process in reeling mills. During investigation values of the power parameters of the process were recorded for different sizing routes. Conclusions about the special features of the wall sizing process and feasibility of extension of the reeling mill process capabilities were formulated.