Cathodic or anodic protection system and method for independently protecting different regions of a structure
US4437957A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 3, 1982 |
| Grant date | Mar 20, 1984 |
| Priority date | — |
| Expiry date | May 3, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23F13/04
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
To protect a structure immersed in an electrolyte, at least two protection units are located adjacent to different regions of the protected structure. In a preferred embodiment, each of these protection units includes a circuit for applying rectified alternating current voltage between the structure and electrodes immersed in the electrolyte adjacent to the different regions of the structure. Also, each of the protection units includes reference cells to produce direct current voltage between the reference cells and the structure, a measuring circuit coupled to the reference cells for measuring the potential between the reference cells and the structure, and a control circuit for controlling the level of the rectified alternating current voltage at the different regions of the structure in accordance with the measured potential levels. The first and second protection units are arranged to be independent of one another so that the level of alternating current voltage applied between the different regions of the structure and the first and second protection units will be independently established. In alternative embodiments, constant current or constant voltage can be applied by the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.