| 摘要 |
PURPOSE:To perform forced-convection cooling with a small amt. of a gaseous refrigerant by introducing and replenishing the gaseous refrigerant to a heat- treating furnace while keeping prescribed pressure, carrying out forced-convection cooling, stopping the additional replenishment of the gaseous refrigerant after the temp. reaches a prescribed value, and continuing the cooling. CONSTITUTION:When heat treatment such as hardening is carried out in a vacuum heat treating furnace, etc., a gaseous refrigerant is introduced into the heat- treating furnace to keep the pressure at a prescribed value, and forced-convection cooling of a material to be heat-treated in the furnace is carried out. During said cooling, the gaseous refrigerant is appropriately replenished to keep the pressure at said specified value. When the temp. of the material to be heat-treated reaches a specified value by said cooling, the additional supply of the gaseous refrigerant is stopped, and the cooling is performed only by the gaseous refrigerant remaining in the furnace. |
