| 摘要 |
<p>The measurement is based on pulse transit times, and uses a meter located above, and aimed at, the melt. The pref. meter uses a laser as the source of the measuring pulses, or alternatively, a source of ultrasonic energy. The pref. appts. consists of a laser meter located on the top end of a vertical, cooled lance which has its lower end in a converter; and gas, esp. oxygen, is blown through the lance, e.g. in the refining of steel. The lance can be adjusted vertically, and the laser beam travels through the bore of the lance. A control circuit is pref. used to measure and adjust the distance of the lance outlet from the surface of the melt. The signals from the laser meter can be used in the automatic control of the melting process.</p> |
