Plasma transferred arc produces the induced electromagnetic field that makes liquid metal convect in molten pool in the surface metallurgical course.

表面冶过程中束产生感生磁场,使熔池内液态属产生对流运动。

The indicator light is lit, the switch of fan shall be turned on as soon as the instrument is warm, so that the heat produced can be forced to convect through the air channel.

指示灯亮，仪器加温后即应打开风机开关，使其热量往风道强制对流。