| 摘要 |
<p>1477119 Rapidly cooling annealed material FRIED KRUPP HUTTENWERKE AG 22 Dec 1975 [30 Dec 1974] 52405/75 Heading C7N Annealed material is allowed to cool to an intermediate temperature and is then cooled rapidly by introduction of a liquefied inert gas into the furnace. Preferably the intermediate temperature is one-third to one-fifth of the annealing temperature, measured in ‹C and the liquid is introduced as a whirling jet to directly contact the material; the liquid may be CO 2 , which is initially vented from the furnace until its purity reaches 99À7%, when it is recycled. In a particular embodiment liquid gas is supplied through line L, to a battery of furnaces O each of which is provided with a gas analyzer Q. When the initially impure gas has been vented valve P is closed, and pure gas recycled through heat exchanger H to gasometer G or recondensing unit V and liquid storage tank S.</p> |
