Avtomaticheskaya Svarka (Automatic Welding), #4, 2021, pp.
Influence of liquid glass characteristics on quality of coating formation of welding electrodes
A.E. Marchenko1, I.O. Glot2, М.V. Skoryna1
E.O. Paton Electric Welding Institute of the NAS of Ukraine.
11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: email@example.com
Institute of Continuous Media Mechanics of the Ural Branch of the RAS, 1, Academician Korolyov Str., 614018, Perm, Russia
The viscosity of 6% dispersions of Na-CMC in liquid Na- and K-glasses depending on temperature, as well as viscosity of pure
liquid Na, K- and NaK-glasses depending on excess pressure and temperature was studied. Each of them represents a consistent
medium of real electrode coating masses. Using the obtained results, by mathematical methods the functioning of the model of the
joint effect of overpressure and dissipative heating on viscosity, velocity profile and stability of pressure flow of electrode coatings
in the step channel under the conditions of coating formation by extrusion deposition on steel bars was verified. Although two
competing sources of change in shear viscosity of the coating mass (temperature and pressure) are available, the calculations did
not reveal situations with unstable (pulsating) flow modes through a suddenly narrowing channel, which could cause instability
of the coating mass flow, and therefore electrode coatings with a thickness variation. At least, they were revealed in the studied
range of capillary L/Rk <10 sizes and pressures, at which the electrodes are actually pressed. 10 Ref., 1 Tabl. , 8 Fig.
Keywords: arc welding, coated electrodes, production technology, coating thickness variation, rheology, viscoelasticity of
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