Selection of vacuum pressure and vacuum implication
position during steel making through RH degasser for maximizing recirculation process

Abstract

Application of low carbon steel and ultra-low carbon (ULC) steel has been improved significantly in recent days in different field mostly in automobile industry for making the body parts of vehicle and also for making home appliances body. However, it is not so easy get steel at a level less than 20 ppm in ladle steel making, so many technologies are developed to get ULC steel from them like ladle vacuum degassing and Ruhrstahl Heraeus degassers are the most famous and popular amongst all of them. In RH degasser, by reducing the system pressure and by injecting inert gas into the up snorkel ,the liquid steel rises into the vacuum vessel where decarburization and other reactions takes place.Contionous recirculation of liquid steel inside the RH degasser reduces the percentage of carbon inside the steel and also removes the harmful gasses which are present inside the steel.Normally, in liquid steel gases like hydrogen, nitrogen are entrapped when these gases are realised after solidification cause cracking, porous holes in the steel structure. In modern steel industry, RH-OB are used. Where oxygen is blown into the vacuum vessel to get the ULC steels. In recent days,so many methods and models are used to make RH process more optimistic like increasing snorkel diameter, using magnetic field, application of multi snorkel etc. In present study, maximization of recirculation rate is improved by choosing proper vacuum pressure and location of implication vacuum pressure inside the vacuum chamber. So three different locations are choose for 3 different pressure each at one location flow path lines are analysed. By the use of fluent tool flow path lines are drawn where best location and pressure is choose.