Ensuring precision characteristics of equipment for rotary extrusion in the production of special technical products

Abstract

Background. The level of development of mechanical engineering significantly affects the economic potential and defense capability of the state. One of the main areas of mechanical engineering is the manufacture of products for aerospace technology. Thus, for the manufacture of liquid rocket engines, an important element is the nozzle part of the combustion chamber. It is a package of equidistant ogival shells, with increased requirements for the thickness variation of the resulting workpiece and deviation from the profile. The objective of the work is to produce competitively and economically viable products. Materials and methods. The most promising method for obtaining ogival shells is the method of rotational extrusion. Thus, to produce ogival thick-walled shells, Design bureau of chemical automation uses the KhTRV-2500 mill. Long-term operation and lack of modernization led to frequent failures in the control system and loss of accuracy and performance characteristics. Results. Thus, to increase the efficiency and reduce the energy intensity of the equipment, the electromechanical part of the mill was modernized by replacing the main two-motor thyristor direct current drive of the mandrel rotation with one asynchronous servomotor, while maintaining the sum of the motor torques. All feed servomotors have been replaced with asynchronous servomotors of lower power and torque. The element base has been completely updated and the outdated control system has been replaced. As a result of the modernization, the accuracy of the rolling rollers has been increased, as well as the speed of their approach and retraction, while ensuring an accurate change in the ratio of the feed speeds of the rollers and the rotation of the workpiece. Conclusions. The modernization of the unique specialized equipment allowed to ensure stable production of complex large-size ogival-shaped parts for special equipment products with increased accuracy and technological characteristics.

Keywords

• shell
• engine
• extrusion
• rotary drawing
• rolling mill
• modernization