Method and apparatus for producing carbon dioxide pellets
US5301509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1992 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | Jul 8, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B32/55
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
There is provided a method and apparatus for practicing carbon dioxide particle blasting utilizing dense carbon dioxide pellets which have been formed by converting the solid carbon dioxide into liquid, flowing that liquid within a plurality of die openings, and transforming the liquid back into the solid phase while still within the die opening. This method includes the formation of a carbon dioxide cake within a snow barrel, urging the carbon dioxide cake against an upstream surface of a die plate having a plurality of die openings with such pressure such that the carbon dioxide becomes liquified within or adjacent the entrance of the die opening due to the pressure, responding as a super viscous liquid, and flowing within a portion of the respective die openings as a liquid. Along the length of the die openings, the liquid changes phase back to the solid state, while the die openings maintain compression (accompanying the back pressure) on the CO.sub.2 to create pellets having a high density. The pellets are thereafter transported to an application nozzle and directed against a workpiece.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.