In this paper the authors present an unusual method for bottom forming applicable for various industrial purposes including the manufacture of water heaters or pressure equipment. This method allows for the fabrication of the bottom of a given piece of stainless steel into a pre-determined shape conforming to the DIN standard which determines the most advantageous dimensions for the bottom cross section in terms of working pressure loading. The authors checked the validity of the method in a numerical and experimental way generating a tool designed to produce bottoms of specified geometry. Many problems are encountered during the design and production of parts, especially excessive sheet wrinkling over a large area of the part. The experiment showed that a lack of experience and numerical analysis in the design of such elements would result in the production of highly wrinkled parts. This defect would render the parts impossible to assemble with the cylindrical part. Many tool shops employ a method for drawing elements with a spherical surface which involves additional spinning, stamping, and grading operations, which greatly increases the cost of parts production. The authors present and compare two forming methods for spherical and parabolic objects, and experimentally confirm the validity of the sheet reversing method with adequate pressure force. The applied method produces parts in one drawing operation and in a following operation that is based on laser or water cutting to obtain a round blank. This reduces the costs of tooling manufacturing by requiring just one tool which can be placed on any hydraulic press with a minimum force of 2 000 kN.
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