Propulsion cleaning system
US5720824A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1996 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | Aug 1, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23G1/106
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method is provided for removing metal oxide debris from various types of surfaces, both metallic and nonmetallic. Specifically, the surface to be cleaned is treated (preferably by immersion) with a preheated solution of 65 to 71 wt % (55.3 to 62.0 vol %) nitric acid, which is roughly equivalent to reagent grade nitric acid. The temperature of the solution is within the range of about 160.degree. to 175.degree. F. (71.degree. to 79.degree. C.). The preheated solution dissolves any metal oxide debris present on the surface, which may then be rinsed away following treatment. The method effects the removal of metal oxide residue from surfaces without further degrading the surfaces being cleaned. Further, the method is capable of cleaning internal surfaces of components without requiring disassembly of sealed or welded components, since all that is needed to effect cleaning is contact between the surface to be cleaned and the preheated solution. Finally, the method is easily implemented since it involves only the simple steps of contacting the component with a single preheated component that is widely available, namely reagent grade nitric acid, followed by rinsing and drying.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.