Method and apparatus for PCVD internal coating a metallic pipe by means of a microwave plasma
US4897285A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 13, 1989 |
| Grant date | Jan 30, 1990 |
| Priority date | — |
| Expiry date | Jun 13, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32678
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A microwave plasma method/of depositing a coating of a prescribed material on the internal surface of a pipe by means of a reaction of a vapor phase providing a prescribed material in which: PA0 (a) an atmosphere at a pressure less than atmospheric pressure containing the vapor phase is introduced into the pipe, PA0 (b) microwave energy is beamed into the pipe which is propagated along the length of the inside of the pipe, PA0 (c) a magnetic field is generated in a localized area of the pipe in which electron cyclotron resonance occurs for the the frequency of the microwaves, and in which, pressure, field strength of the magnetic field and the power of the high-frequency field are selected that a low-pressure gas discharge results in the area of the magnetic field to trigger the reaction furnishing the prescribed material, and PA0 (d) in which the magnetic field and thus the plasma are transposed along the length of the pipe.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.