Actual Problems in Machine Building 2021 Vol.8 N3-4

Actual Problems in Machine Building. Vol. 8. N 3-4. 2021 Innovative Technologies in Mechanical Engineering ____________________________________________________________________ 74 LOSS OF ACCURACY DURING ELECTRIC DISCHARGE MACHINING AND METHODS OF ITS PREVENTION Popov A.Yu. , D.Sc. (Engineering), Professor, e-mail: popov_a_u@list.ru Rechenko D.S. , D.Sc. (Engineering), Professor, e-mail: rechenko-denis@mail.ru Savin A.V. , Postgraduate student, e-mail: oat@oat.ru Prokofev V.A. , Student, e-mail: vladimirprokofev1999@mail.ru Omsk State Technical University, 11 Mira ave., Omsk, 644050, Russian Federation Abstract In the process of electrical discharge machining of cylindrical holes in workpieces made of carbide materials, deviations from the specified dimensions occur. Through experimental research and theoretical calculations, it was argued that the electrode during electrical discharge machining deviates from its axis, including under the influence of pressure from the liquid washing out slags, and the greater the depth of processing, the greater the deviation. The use of a jig, as a guiding device, helps to align the required parameters of the hole being created. The behavior of the electrode inside the hole is similar to a throttle valve and a hydrostatic bearing, a protrusion forms inside the electrode, which can be interpreted as a needle throttle – all this allows to apply calculation formulas to obtain data on the pressure and forces on the electrode inside the hole. The Bernoulli equation, the calculation of the ring stiffness, the calculation of the moments of inertia of the electrode, and the calculation of the holding force in the axis were used as formulas. For the experiments, a high-speed electrical discharge machine for making small holes D720, steel, brass electrodes with an outer diameter of 3.019 mm were used. To analyze the results, a VMM 150 microscope was used. This paper allows understanding the reasons for the deviations of the parameters and what will contribute to its elimination. Keywords Super drill, EDM, electrode, bore precision, butterfly valve, hydrostatic bearing, needle choke, jig.