Deformations Arising During Air-Knife Stripping in the Galvanisation of Steel
During sheet steel production, the steel surface is usually coated with metal alloy for corrosion protection. This can be done by passing the steel through a bath of the molten metal coating, and controlling thickness with a pair of air knives on either side of the ascending steel strip. Surface quality problems have arisen with recent developments in production. The process was considered at the 2009 Mathematics-and-Statistics-in-Industry Study Group in Wollongong (MISG09) and in subsequent investigations. Previous analyses are extended by the addition of shear terms and by exploring the effect of increased air-jet speeds. A first-order partial differential equation governs the system. This may be used to determine the steady-state coating shape and to study the evolution of any defects that may form.
KeywordsCoating Thickness Corrosion Protection Capillary Number Steel Strip Surface Shear Stress
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