Patent · US Expired

Method for molten metal treatment

US5462580A · kind A · utility

15Cited by
4References
21Claims
0Family size

Inventor

Key dates

Filing dateOct 3, 1994
Grant dateOct 31, 1995
Priority date
Expiry dateOct 3, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/25
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Disclosed is an improved method for dispersing a treatment media in a body of molten metal using an impeller, nozzles, and other mixing means to disperse the media in the body of molten metal, the method producing increased shear forces in the body of molten metal and preferably reducing vortex formation. In one embodiment, the method comprises the steps of providing a body of molten metal and an impeller on a shaft in the body. A treatment media is added to the body and dispersed by rotating said impeller in one direction and thereafter reversing the direction of rotation of the impeller to a counter direction. The direction of rotation of the impeller is reversed periodically to substantially reduce formation of a vortex around the shaft of the impeller and to provide increased shear forces in the body for purposes of improving treatment of the molten metal by improved dispersion of the media therein. Further, the reversal of direction of the impeller increases the radial velocity gradient of the molten metal thereby increasing shear forces. This creates numerous subsurface streams which has the effect of dispersing small gas bubbles throughout the melt. This substantially improv…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.