Method for reducing metal oxide formation on a continuous metal sheet in the hot dip coating thereof
US4183983A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 1978 |
| Grant date | Jan 15, 1980 |
| Priority date | — |
| Expiry date | Aug 17, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C2/0224
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Sealing means for preventing metal vapor, and in particular zinc vapor, evolution from the surface of a bath into a furnace is provided at the exit end of the heat processing industrial furnace through which a continuous metal sheet is advanced. Upon exiting the furnace the metal sheet is dipped into a bath for hot dip coating thereof. At the zone of the industrial furnace from which the continuous metal sheet exits the furnace and advances into the coating bath, there is provided therein an atmosphere having a low dew point and a relatively high hydrogen content to thereby reduce the oxidation of the metal vapor which may have migrated into the furnace. Furthermore, sealing means are provided between zones of the furnace to retain the integrity of this atmosphere, and thus isolating zones having different atmosphere compositions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.