Technological Design of Methods for Manufacturing U-Shaped Helical Surfaces of Transport Pipes

The process of technological design and manufacturing of special screw blanks is accompanied by a number of technical and production problems that require systematic analysis and comprehensive solutions. One of the main problems is the difficulty of ensuring high accuracy of the geometric parameters of screw surfaces, especially in conditions of single or small-scale production. Such surfaces have a complex spatial shape, which requires the use of specialized tools, high-precision equipment and modern control methods. Another important challenge is the choice of the optimal method of forming the workpiece depending on the material, design requirements and operating conditions. In this case, it is necessary to take into account not only technical characteristics, but also the economic feasibility of production, equipment costs, and energy intensity of the process. Another problem is achieving the required mechanical properties of the product (strength, wear resistance, fatigue endurance), which often requires the implementation of additional technological operations, in particular heat treatment or surface hardening. All these factors complicate technological planning, increase the risks of defects and increase the cost of production. Thus, the main problem is to develop rational and technically efficient technological methods that are capable of ensuring the manufacture of special screw blanks with the required characteristics at minimal production costs. Modern scientific works in this area of research highlight a wide range of approaches to obtaining special screw blanks, including methods of winding, rolling, stamping, pressing, etc., each of which has its own advantages and limitations depending on the type of material, spiral geometry, and operating conditions of the product. Particular attention is paid to increasing the manufacturability of special equipment designs, in particular by improving design solutions, reducing energy consumption and material consumption in the manufacturing process, as well as developing specialized technological tools. Recent research in the field of technological design and manufacturing of special screw blanks covers a wide range of innovative approaches aimed at increasing production efficiency, reducing energy consumption, and improving product quality. In particular, such approaches as multi-level classification of screw and auger billet designs were proposed; morphological analysis for the synthesis of new methods of winding screw billets; optimization of technological processes for manufacturing screw billets, in particular, by unifying designs and implementing modern design methods. The work substantiates four new methods for manufacturing U-shaped helical surfaces of transport pipes using frames and forming rollers. The developed methods can be implemented in different ways. In particular, by indenting U-shaped ridges on the finished pipe, or by simultaneously winding and U-shaped indenting a rectangular-section strip onto a frame with a U-shaped spiral protrusion, followed by fastening the protrusions of the wound strip with a weld. In general, the developed methods for manufacturing U-shaped helical surfaces of transport pipes can be conditionally divided into two types - with the possibility of changing the height of the U-shaped ridge by changing the diameter of the spring bar, and without such a possibility, in which frames with a constant height of the U-shaped ridge are used. The work also defines and characterizes the structural materials for the manufacture of helical transport pipes. As starting materials, it is advisable to use seamless cold- and hot-rolled pipes, cast pipes, and cold-rolled strip products. For both types of methods, rational structural and technological parameters for their implementation are defined and presented.