Bauman Moscow State Technical University (National Research University), Kaluga Branch, Kaluga, Russia

A. G. Vyatkin, Cand. Eng., Associate Prof., Dept. MK1 of Mechanical Engineering Technologies
A. A. Vyatkin, Senior Lecturer, Dept. MK4 of Engineering Graphics, e-mail: a-vyatkin@bmstu.ru

The calculation and analytical method for determining the error in the height of forgings during upsetting on a hydraulic press without a stop and with the use of a stop is considered. To calculate the expected error, the theory of parametric sensitivity is used, which allows using the sensitivity function, which shows how the initial errors are transformed into the error in the height of forgings. The obtained sensitivity functions allow us to determine that during upsetting on a hydraulic press with the use of a stop, it is possible to ensure the accuracy of the forging height of successive upsetting, exerted on a crank press. The different nature of the influence of forging rigidity, characterized by the ratio of diameter to height, on the accuracy of forging height is determined. When upsetting without a stop, with an increase in forging rigidity, the height error decreases, while when upsetting with a stop, it increases. This article is devoted to the calculation and analytical method for determining the expected error in forging height when upsetting on a hydraulic press using a rigid stop.

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