ISSN (print) 1995-2732
ISSN (online) 2412-9003

 

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Abstract

The purpose of the work is to study the effect of the electrolyte feed rate on the quality of coating.

There is SMS Cheltec in Chelyabinsk, a joint Russian and German company which does protective coatings for copper plates used in continuous casting crystallizers. A nickel-cobalt coating is one of the coating types used. An uneven hardness defect is typical of this coating which can go across the whole area of the plate. To look into what causes the defect and how it develops hardness measurements were taken and aggregated in a chart.

Through the study of specialist literature it has been determined that the defect can possibly be caused by a poorly blended electrolyte in the contact area with the plate. To verify this hypothesis mathematical modelling of the working fluid dynamics was done. The Solid Works software was used for the modelling which produced a chart showing electrolyte flow rates in the contact area. Comparison of the test data with the plate hardness chart confirmed that the assumption was correct.

In order to eliminate the defect it was suggested that the feed pump discharge rate should be changed. Based on the available standard model a mathematical experi-ment was conducted when the electrolyte feed rate was changed with the rest of the process parameters remain-ing unchanged. The increased pumping rate produced a positive effect on the working fluid recirculation rate in the contact area. Reduction of the feed rate produced the opposite effect.

The mathematical modelling done at different feed rates has demonstrated that the fluid feed rate does have an effect on the nickel-cobalt plating process.

Keywords

CC machine, crystallizer, uneven hardness defect, electrolyte feed rate.

 

Sherkunov Viktor Georgievich – D.Sc. (Eng.), Professor, South Urals State University, Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

Rednikov Sergey Nikolaevich – Ph.D. (Eng.), Assistant Professor, South Urals State University, Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

Vlasov Aleksandr Evgen'evich – Postgraduate Student, South Urals State University, Chelyabinsk, Russia. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

Pino Tese – Associate Professor, Executive Vice President of SMS Siemag AG, Germany. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

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