Vacuum Circulation Process (RH)

The RH (Ruhrstahl Hereaus) Process is carried out in a refractory lined vessel equipped with two snorkels which are immersed in the steel bath. By reducing the system pressure and by injecting inert gas into the upleg snorkel the melt rises into the vacuum vessel where decarburization and other reactions take place. The RH Plant is the best suitable system for the production of Ultra Low Carbon Steel grades.

 

 

 

Metallurgical and operational tasks:

  • Fast decarburization down to 15 ppm
  • Hydrogen and Nitrogen degassing
  • Operation possible with varying initial carbon contents (with top oxygen blowing)
  • Flexibility to use lower cost HC alloying materials
  • Chemical heating of killed and unkilled heats
  • Improved steel cleanliness with regard to nonmetallic inclusions
  • Exact compositional values within narrow tolerances of liquid steel