Generalized and analyzed are the results of investigations carried at the E.O. Paton Electric Welding Institute on technological properties of electrode compounds, promoting thickness difference of electrode coatings. The investigations were carried out using capillary viscosimeter of fixed flow-rheometer with electric drive, which can be used for simulation of the conditions of compound extrusion application over the electrode rods, typical for commercial electric extrusion presses. Thus, specific pressure on compound under condition of stationary flow achieves 60-75 MPa, average gradient of shear rate is gradually regulated in the ranges from 1 to 5⋅10 3 s-1 , and it makes to 65⋅10 3 s-1 for separate types of compound. The compounds for rutile, low-hydrogen and cellulose electrodes, differing by wide range of consistency indices, were investigated. In addition to shear and longitudinal viscosity, the investigations were carried out on a range of change of their modulus of shear elasticity, period of relaxation, criterion of Reynolds elastic turbulence, elastic potential and reversible (elastic) deformation. The results received were analyzed from point of view of existing phenomenological theory of elastic turbulence of polymer materials, combining viscosity and elasticity properties. It is successfully used in the course of many years in rheology of melts and solutions of high-molecular compounds for solving of technological problems of their extrusion processing. Variants of elastic turbulence, detected in capillary and pre-capillary zones, were analyzed. Quality relation of this phenomenon to appearance and nature of coating thickness difference in course of real extrusion application of compound over the electrode rods was shown. 24 Ref., 4 Tables, 9 Figures.

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This issue of journal contains scientific-technical papers and papers dedicated to industrial points, prepared by the specialists in the field of development, production and application of welding and surfacing consumables. Among the authors are the apprentices and followers of Prof. I.K. Pokhodnya, heads and specialists of a series of enterprises manufacturing welding consumables. Readers of the journal will also be able to familiarize with current market of welding consumables in Ukraine, examples of successful organization of production and realization of the products, recommendations on increase the competitiveness of domestic welding consumables. Editorial note EffEct of bindEr typE on manufacturability and propErtiEs of E-08Kh20n9G2b typE coatEd ElEctrodEs K.a. yusHcHEnKo, a.V. bulat, n.V. sKorina, a.E. marcHEnKo, V.i. samoJlEnKo and n.yu. KaKHoVsKy E.

It is determined in course of investigation of compound of low-hydrogen electrodes UONI-13/55, carried out with the help of capillary viscosimeter, that their rheological indices and structure under flow pressure condition significantly depend on grain composition of coating materials. Charge should contain 50 % of fine fraction from point of view of minimizing of energy consumption, necessary for extrusion application of compounds on rods. Deviation of its portion in one or another side from indicated optimum significantly rises energy consumption on electrode extrusion. The compounds with fine-or coarse-grain filler are not similar to each other on structure. It confirms nature of change of level of compound dissipative heating, value of natural convergence angle in entrance zone (to capillary) as well as shape of deformation (extrusion) curves at increase of flow velocity. Profile of flow of compounds with coarse-grain filler expands at rise of pressure jet rate. It remains virtually of the same narrow shape as at creep flow velocities for flow of compounds with fine-grain filler. The results of analysis of form of extrusion curves P = f(t) indicate that pressure flow of compound with coarse-grain filler is realized on viscosity mechanism. The compounds with excessive content of fine-grain filler are more structured, since liquid glass binder in these cases in addition to filling of intergrain voids should cover significantly more developed grain surface. Rise is observed in their molecular interaction and strength of structure formed by them, which is fractured in deformation and accompanied by specific phenomena of unsteady flow. 8 Ref., 2 Tables, 8 Figures. K e y w o r d s : low-hydrogen welding electrodes, coating thickness difference, rheology of compounds, viscosity and elasticity indices of compounds

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