Minimizing Zinc Coating Section Downtime of Continuous Galvanizing Line in Steel Industry

Abstract

Galvanizing is a technique of smearing a protective Zinc coating on Steel or iron, to avert its rusting. The usual practice to produce galvanized steel is through hot dip galvanizing method. It is a continuous line where annealed sheet is immersed into molten Zn bath with Sink roll assembly guiding the sheet and air knife system maintaining proper coating of Zn onto the sheet. Due to high vibration sink roll bushes get wear frequently and scratches are formed on sheets, as a quality defect. The vibration causing element is to be identify and resolving it reduces the sink roll changing frequency and increases Zn coating section availability time, also minimizes the scratch formation on sheet during coating. The data were collected, analyzed and implemented to increase the availability time of Zn coating section, and thus the productivity.

Keywords: Corrector and Stabilizer roll , Cause and effect analysis ,Dross formation, Hot dip galvanizing,  Pareto analysis , Sink roll assembly vibration, Zinc coating,