Study of the integrated process of cutting and longitudinal upsetting of high-precision workpieces using the energy of elastic unloading of the press
摘要
This paper investigates an integrated blank separation process combining cutting and plastic deformation (longitudinal upsetting) to ensure high volumetric and geometric accuracy. The relevance of the study stems from the need to produce high-quality blanks for cold forging and extrusion, where simple blanks made from long rolled products often exhibit unacceptable dimensional deviations. Based on 3D finite element modeling in DEFORM software and experimental studies, an optimal two-support cutting scheme was determined. Unlike cantilever (single-support) cutting, this scheme creates oppositely directed inclination angles at the ends of the blank, minimizing their axial displacement and preventing loss of stability during subsequent upsetting. A key feature of the proposed method is the use of elastic press unloading energy, which is typically considered «detrimental» due to the vibrations and impact loads it imposes on the equipment. The authors demonstrated that this energy can be redirected to perform useful work during plastic forming. Calculations and experiments showed that the work required for double-sided cutting is approximately 53% of that required for longitudinal upsetting. This energy is sufficient to correct the shape of the workpiece; however, achieving high accuracy requires the use of additional energy sources in modernized presses with combined dies. As a result of the research, a die design was developed and proposed that implements an integrated cutting and longitudinal upsetting process. This design ensures high geometric accuracy of workpieces, increased process productivity, and improved operational reliability of the pressing equipment.