2021 №04 (02) DOI of Article
2021 №04 (04)

Automatic Welding 2021 #04
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
1E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
2Institute 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 coating masses

Received: 22.03.2021


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