Rotary plasma spray method and apparatus for applying a coating utilizing particle kinetics
US6986471B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2002 |
| Grant date | Jan 17, 2006 |
| Priority date | — |
| Expiry date | May 15, 2023 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05D1/007
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of operation of a plasma torch and the plasma apparatus to produce a hot gas jet stream directed towards a workpiece to be coated by first injecting a cold high pressure carrier gas containing a powder material into a cold main high pressure gas flow and then directing this combined high pressure gas flow coaxially around a plasma exiting from an operating plasma generator and converging directly into the hot plasma effluent, thereby mixing with the hot plasma effluent to form a gas stream with a net temperature based on the enthalpy of the plasma stream and the temperature and volume of the cold high pressure converging gas, establishing a net temperature of the gas stream at a temperature such that the powdered material will not melt or soften, and projecting the powder particles at high velocity onto a workpiece surface. The improvement resides in mixing a cold high pressure carrier gas with powder material entrained in it, with a cold high pressure gas flow of gas prior to mixing this combined gas flow with the plasma effluent which is utilized to heat the combined gas flow to an elevated temperature limited to not exceeding the softening point or melting point of the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.