Tula State University (Tula, Russia):

S. N. Larin, Dr. Eng., Prof., Dept. “Mechanics of Plastic Shaping”, e-mail: mpf-tula@rambler.ru
V. I. Platonov, Cand. Eng., Associate Prof.
P. V. Romanov, Student

Scientific and Production Union “Splav” named after A. N. Ganichev (Tula, Russia):

A. N. Isaeva, Engineer

The issue of increasing the efficiency of metal forming processes by combining the operations of drawing with thinning of the wall and extrusion in the manufacture of cylindrical articles having a thick bottom and thin wall. The ratio of height to diameter can vary from 1 to 10 and more. These are various connectins, adapters, unions, elements of cases, sleeves and other articles with a wall thickness less, than thickness of a bottom. Rolled sheet metal made of various grades of steel, brass, aluminum, titanium and other materials can be used as workpiece materials. The combination of drawing operations with wall thinning and extrusion at one working position allows to significantly expand the technological capabilities of metal forming, reduce the number of steps, improve the quality of articles. Compared to backward extrusion, the proposed technology provides a lower level of stress in the tool and workpiece, enabling to use less powerful hydraulic press equipment and significantly increase the durability of stamping equipment. When using blanks with planar anisotropy, this technology allows not only to eliminate earing on the edge surface of the semi-finished product and get a smooth face end of the product, but also to form any other profile of the edge of the part. The formation of articles without earing eliminates the operation of trimming the end face of the semi-finished product, which significantly increases the utilization of the material and reduces the cost of finished articles. The method for calculation of geometrical parameters of stamping equipment to obtain defect-free articles is given. Theoretical studies of the combination of drawing operations with thinning and extrusion of the cylindrical workpiece were carried out by the finite element modeling method using the QFORM software package. The scheme of universal experimental stamping equipment is shown.

The work was performed under the grant NSh-2601.2020.8.

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