Title:
DEW FORMATION PREVENTING METHOD IN WATER-COOLED VACUUM HEAT TREATMENT FURNACE
Document Type and Number:
Japanese Patent JP3486921
Kind Code:
B2
Abstract:
PURPOSE: To prevent dew formation by a method wherein with cooling water to a cooler and a jacket stopped, a circulation fan remains operated before a furnace door is opened to keep the inner surface temperatures of a furnace main body and a furnace cover higher than the outside temperature.
CONSTITUTION: A work A is heated up to a specified temperature and then cooled down in a treatment chamber 22. Cooling is performed in such a manner that a cooling valve 61 is opened to introduce cooling gas, for example, nitrogen gas, into a furnace until the inside of the furnace reaches a specified pressure and a circulation fan 41 is operated. After the work A is cooled down, when the circulation fan 41 continues to operate with valves 62 and 63 closed so that the inside of the furnace is heated by heat generated. When the inner surface temperatures of a furnace main body 11 and a furnace door 12 become higher than the outside temperature, the fan 41 is stopped and the furnace door 12 is opened to take out the work A. Thereby, dew formation can be prevented by using heat generated by the rotation of the circulation fan 14 which is to cool down the work A originally.
Inventors:
Shinobu Inuzuka
Makoto Ogihara
Makoto Ogihara
Application Number:
JP19922593A
Publication Date:
January 13, 2004
Filing Date:
July 15, 1993
Export Citation:
Assignee:
Daido Steel Co., Ltd.
International Classes:
C21D1/773; F27B17/00; (IPC1-7): F27B17/00; C21D1/773
Domestic Patent References:
| JP6145587A |
Attorney, Agent or Firm:
Hiromasa Iriyama
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