Induction furnace for high temperature operation
US6898232B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 3, 2004 |
| Grant date | May 24, 2005 |
| Priority date | — |
| Expiry date | Mar 3, 2024 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF27D2099/002
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
An induction furnace capable of operation at temperatures of over 3100° C. has a cooling assembly (60), which is selectively mounted to an upper end of the furnace wall (76). The cooling assembly includes a dome (62), which is actively cooled by cooling water coils (68). During the cool-down portion of a furnace run, cooling initially proceeds naturally, by conduction of heat away from the hot zone through a furnace insulation layer (58). Once the temperature within the furnace hot zone (20) reaches about 1500° C., a lifting mechanism (80), mounted to the dome, raises a cap (16) of the furnace slightly, allowing hot gases from the hot zone to mix with cooler gas in the dome. This speeds up cooling of the hot zone, reducing cool-down times significantly, without the need for encumbering the furnace itself with valves or other complex cooling mechanisms which have to be replaced periodically. The life of a graphite furnace susceptor (10) at the high operating temperature is increased by surrounding the susceptor with a barrier layer (40) of flexible graphite, which inhibits evaporation of the graphite. Additionally, witness disks (154), placed within the susceptor, provide an accurat…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.