Electric heating – Inductive heating – With heat exchange
Reexamination Certificate
2000-06-02
2003-10-28
Van, Quang T. (Department: 3742)
Electric heating
Inductive heating
With heat exchange
C118S724000, C219S494000
Reexamination Certificate
active
06639196
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to method and an apparatus for cooling a furnace configured for processing refractory composites. More specifically, the invention is directed to method and apparatus for cooling a furnace more rapidly than known prior art methods.
Processing of refractory composites takes place at elevated temperatures. Such processing includes CVI/CVD deposition of a binding matrix within a fibrous preform structure, and heat treating refractory composites. According to conventional practice, the furnace is allowed to cool statically under vacuum or it is back-filled with an inert gas such as nitrogen. Cooling the furnace to a low enough temperature wherein the furnace may be opened can take days according to this method. In addition, cooling the furnace too rapidly or introducing a reactive gas, such as oxygen, can cause damage to the furnace itself or the refractory composites being processed in the furnace. Therefore, a method and apparatus is designed whereby the furnace and the refractory composites are cooled more rapidly and at a controlled pace than conventional known methods without causing damage to the composites.
BRIEF SUMMARY OF THE INVENTION
According to an aspect of the invention, a method is provided for cooling a furnace configured to process refractory composites, comprising the steps of: flowing a cooling gas in a closed circuit through the furnace, over the refractory composites disposed within the furnace, and over a cooling element disposed within the furnace. The method according to the invention may further comprise the step of flowing the cooling gas by natural convection. The method according to the invention may also further comprise the step of flowing the cooling gas by forced flow.
According to a further aspect of the invention, a furnace configured to process refractory composites and a cooling system therefor is provided, comprising: a furnace shell that defines a furnace volume; a heater disposed within the furnace shell; a cooling element disposed within the furnace shell; an inlet conduit connected to the furnace shell in fluid communication with the furnace volume; an outlet conduit connected to the furnace shell in fluid communication with the furnace volume; a cooling gas supply configured to selectively introduce a cooling gas into the furnace volume; and, a blower connected to the inlet conduit and the outlet conduit in fluid communication therewith, wherein activation of the blower causes cooling gas introduced into the furnace volume to flow through the blower, through the inlet conduit, over the cooling element, through the outlet conduit, and back to the blower in a closed circuit.
The invention includes various other aspects as presented by the detailed description that follows.
REFERENCES:
patent: 1933461 (1933-10-01), Toll
patent: 3470624 (1969-10-01), Plotkowiak
patent: 3850417 (1974-11-01), Elorza
patent: 3884793 (1975-05-01), Penfold et al.
patent: 3995187 (1976-11-01), Penfold et al.
patent: 4030996 (1977-06-01), Penfold et al.
patent: 4031424 (1977-06-01), Penfold et al.
patent: 4422407 (1983-12-01), Bessot et al.
patent: 4490108 (1984-12-01), Petzi
patent: 4573431 (1986-03-01), Sarkozy
patent: 4582301 (1986-04-01), Wunning
patent: 4606650 (1986-08-01), Harris
patent: 4794220 (1988-12-01), Sekiya
patent: 4802441 (1989-02-01), Waugh
patent: 4846675 (1989-07-01), Soliman
patent: 4854266 (1989-08-01), Simson et al.
patent: 4979896 (1990-12-01), Kinoshita
patent: 5073241 (1991-12-01), Watanabe
patent: 5127827 (1992-07-01), Hoetzl et al.
patent: 5377297 (1994-12-01), Nuutinen
patent: 5470452 (1995-11-01), Dickey et al.
patent: 5480678 (1996-01-01), Rudolph et al.
patent: 5589421 (1996-12-01), Miyashita et al.
patent: 5616264 (1997-04-01), Nishi et al.
patent: 5625170 (1997-04-01), Poris
patent: 5702531 (1997-12-01), Mikata
patent: 5725746 (1998-03-01), Dickey et al.
patent: 5748666 (1998-05-01), Andersson et al.
patent: 5853485 (1998-12-01), Rudolph et al.
patent: 5900297 (1999-05-01), Rudolph et al.
patent: 5910006 (1999-06-01), Conroy et al.
patent: 6162298 (2000-12-01), Rudolph
patent: 0 410 442 (1991-01-01), None
patent: 0 832 863 (1998-01-01), None
patent: 0 846 787 (1998-06-01), None
patent: 0 995 960 (2000-04-01), None
W.V. Kotlensky,Deposition of Pyrolytic Carbon in Porous Solids, 8 Chemistry and Physics of Carbon, 173, 190-203 (1973).
W.J. Lackey,Review, Status, and Future of the Chemical Vapor Infiltration Proces for Fabrication of Fiber-Reinforced Ceramic Composites, Ceram. Eng. Sci. Proc. 10[7-8] 577-81 (1989).
J. Linke et al.,Behavior of Boron Doped Graphites, Plasma Sprayed B4C, and a —C/B:H as Plasma Facing Material, Fus. Tech. 20, 228-231, (9/91).
Ponnekanti et al.,Failure mechanisms of anodized aluminum parts used in CVD chambers, J. Vac. Sci. Tech. A14(3), (5/96).
Fiala Robert
Garn Dennis T.
Lee Jerry S.
Rudolph James W.
Brinks Hofer Gilson & Lione
Goodrich Corporation
Van Quang T.
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