Nozzle for oxygen-injection lances used in the decarburisation of pig iron, in particular chromium pig iron

摘要

The new nozzle which is the subject of the invention relates to the decarburization of liquid cast irons by means of an oxygen jet coming from a lance equipped with such a nozzle. The nozzle according to the invention is characterized by a diverging portion which comprises, beyond the neck, a frustoconical part with an angle at the apex between 60 and 70 ° and preferably between 62 and 66 °. The angle of 65 ° is close to the optimum. The nozzle according to the invention applies in particular to the decarburization of chromium cast irons and allows very high yields of chromium and iron to be obtained.