The Study On Oxide Scale Defects Reduction Of Hull Structural Steel

It has higher requirements on surface quality of hull structural steel. Inthe processing of hull structural steel, due to various reasons, the surfaceoxidation of steel cannot be effectively removed. Once the oxide scale ispressed into the surface of the plate, it had not been removed byhigh-pressure descaling water, it will eventually form the primary scale.Secondary oxide scale formed on the surface of hot rolled steel duringfinishing and the subsequent cooling processes. With the increasingly fiercemarket competition, improving the surface quality of plate, especially toreduce the defects of scale become the wide and heavy plate manufacturersneed to face the problem.In this paper,,the author analyzed the factors of chemical composition,heating system, descaling equipment and system, and others things howto influence the scales based on the actual situation of the production line.By experiments and simulations, the oxide scales can be reduced thoughreduce the content of Si and the heating temperature; tested by experimentand simulations, the deficiencies of the nozzles currently in used had showedto us and a reasonable model of nozzle had been determined by simulations; in order to strengthen the effects on descaling, extension the descaling timewas also being uesd; the new reasonable rolling process was also beingdetermined by contrasting different process researchers.It showed that the reduction of the oxidation scale defects was obviouslyafter the improvements finished mentioned above.It recognized by theforeign shipbuilding enterprises.