Gas permeable stopper rod
US4791978A · kind A · utility
13Cited by
6References
24Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 25, 1987 |
| Grant date | Dec 20, 1988 |
| Priority date | — |
| Expiry date | Nov 25, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22D41/186
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A one-piece carbon-bonded graphite refractory stopper rod for use in continuous casting of molten metal includes a copressed body portion with an integral porous nose section. Through a gap grain sizing technique, the mean pore size of the nose is controlled to preferably about 10 microns to permit an inert gas introduced into the rod to permeate therethrough as a fine dispersion of bubbles in the melt while preventing reverse permeation of molten metal in the event of depressurization of the gas supply. Improved erosion resistance of the nose and lower alumina deposition in the casting nozzle are also achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.