“Ligth Metals” Ltd., Krasnoyarsk, Russia:
Yu. N. Popov, Deputy International Relations Director, e-mail: popov@lmltd.ru

Siberian Federal University, Krasnoyarsk, Russia:

A. V. Mishurov, Senior Lecturer

M. G. Shamsutdinova, Post-Graduate Student

LLC “RUSAL ETC”, Krasnoyarsk, Russia:
A. V. Zavadyak, Head of a Project

apply it for recognizing of anode tendency to technological disturbances formation, such as “spikes” during the aluminium electrolysis. “Spikes” formation has a negative effect on the reduction cell performance, especially on high amperage cells, because it leads to short circuit and performance indicators reduction. In the article different causes of “spikes” formation are considered, while the necessity of anode quality inspection is indicated, because anode defects lead to non-uniform current distribution and increased local anode consumption. Authors describe the destructive method of anode quality control, which is applied widely at production; and its technological scheme is shown. However, the ineffectiveness of the method is demonstrated because it demands more anodes for inspection which leads to increasing the cost of production. Apart from the traditional way of anode quality control by destructive method, the methods of non-destructive control are considered; their reliability and possibility of using at the in-line mass production are estimated. The following non-destructive methods are described: X-Ray tomography; methods based on Ohm’s law; acoustic methods of natural frequency and forced oscillations; acoustic techniques of ultrasound; methods of electrical resistance control using electromagnetic induction. These methods are compared taking into account the maximum size of investigated sample, resolution of devices (minimum size of defined defect), time and performance of measure, cost of equipment. The methods which can be recommended for estimation of anodes quality at the plants were determined on the basis of the article results.
The scientific investigations used the results of works, carried out within the project “Development of superpower, energy-efficient technology of obtaining of aluminium РА-550” (agreement with Ministry of Education and Science of Russian Federation No.02.G25.31.0181 on 01.12.2015).

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