Quality and productivity improvement of electric busbars epoxy coating process by fluidized bed system

Fluidization-bed columns are widely used in the electrical industry, particularly in the insulation of busbars by epoxy coating. Control of the hydrodynamic parameters of the fluidized bed and the loading rate and distribution of solid particles are essential factors in the coating processes of the busbars. Successful control of the fluidized bed hydrodynamic parameters and solid particles loading rate reduces the waste in the manufacturing of the busbars. The objective of the present work is to investigate and improve the effect of solid loading and the properties, of both single and binary mixtures, on the hydrodynamic parameters of the fluidized bed to standardize the epoxy coating process of the busbars. All data acquisition and measurements have been carried out at the production facility of a leading busduct manufacturer. The investigation included compressed air holdup and bubble dynamics of a fluidized–bed bubble column and its influence on the coating performance of the busbars with different compositions of solid particles. The methodology of the study is based on experimental investigation, measurement of the hydrodynamic parameters and analysis of the quality of coating of the manufactured busbars. It was observed that for specified operating conditions, there is a proportional relationship between gas holdup, superficial gas velocity and solid particle diameter, while an inverse relationship exists between the gas holdup and solid concentration versus particles density. Bubble mean diameter and bubble rise velocity are directly proportional to solid concentration and particle diameter.