In the paper there was made an attemp to develop an experimental method of phisi-cal (flash point of the lubricant, T) and subjective (forgings' quality) parameters coupling for isothermal hot forging operation. The quality forgings can be manufactured both by high and low flash point. The increase of Tf value follows to the increase of the released heat amount by the lubricant, because it needs more initial activation energy amount from the external source to initialize transformation of the material from one agregate state into another (from liquid or solid into gaseous or sol-like). This can prevent the temperature decrease on the punch contact surface at the beginning of the punch stroke due to strong convective heat transfer with the environment. On the other side it can cause the defect building on the forgings, which could not be eliminated during washing operation before mechanical treatment. From the obtained diagrams for the normal distribution of the middle temperature values on the punch contact surface the authors of the paper have concluded that the quality forgings can be produced if the temperatures are inside or even outside of the trusted area of 2s.

Рассматривается методика проведения поиска зависимости между физической (температура вспышки смазочного вещества) и субъективной (качество детали) величиной, представленные для процесса горячей изотермической штамповки. Полученные диаграммы нормального распределения средних значений температур показывают, что и при температурах, входящих в интервал 2s, можно получить как качественные, так и бракованные поковки.