| 摘要 |
<p>A hot meal object is quenched after heat treatment. A hot gas stream comprising at least 20 % by volume of hydrogen is taken from for example a carburising chamber (4) of a furnace (2). The gas is cooled by passage through a heat exchanger (16), and is compressed in a compressor (18). The compressor (18) has an aftercooler (not shown) to remove heat of compression from the gas. The cooled, compressed gas flows through nozzles (26) into a quenching chamber (6). The gas leaves the nozzles (26) at a velocity of at least 50 m/s and impinges upon the hot metal object so as to effect its quenching.</p> |
