電極鹽浴爐 通過金屬電極將低壓 (5.5~36伏)大電(dian)流交流電(dian)引入(ru)爐內，電(dian)流流過(guo)鹽(yan)液發熱(re)。鹽(yan)液既是發熱(re)體(ti)，又是對工(gong)件(jian)加熱(re)的介質。鹽(yan)液溫度依鹽(yan)液成分而不(bu)同，一(yi)般在150~1300℃之間。磁場的(de)作(zuo)(zuo)用(yong)(yong)能使鹽(yan)液循環(huan)翻動，有利于鹽(yan)液溫度均勻，又能提高工(gong)件(jian)的(de)加熱速度。電(dian)(dian)極(ji)鹽(yan)浴爐(lu)由電(dian)(dian)極(ji)、耐(nai)火爐(lu)襯、密封金屬爐(lu)罐、絕熱層和爐(lu)殼構成，由專(zhuan)用(yong)(yong)鹽(yan)浴爐(lu)變壓器供電(dian)(dian)。因(yin)固(gu)態鹽(yan)不導電(dian)(dian)，開爐(lu)時先向起(qi)動電(dian)(dian)極(ji)送電(dian)(dian)，利用(yong)(yong)起(qi)動電(dian)(dian)極(ji)的(de)電(dian)(dian)阻發熱使一部分鹽(yan)先熔(rong)化(hua)，然后接通主電(dian)(dian)極(ji)使電(dian)(dian)流通過熔(rong)鹽(yan)發熱工(gong)作(zuo)(zuo)。主電(dian)(dian)極(ji)有插(cha)入式(shi)和埋入式(shi)兩種結構形式(shi)。①插(cha)入式(shi)電(dian)(dian)極(ji):電(dian)極(ji)從(cong)爐口插入爐內。這(zhe)種(zhong)電(dian)極(ji)結(jie)構(gou)簡單(dan)，裝卸方便(bian)。②埋(mai)入式電(dian)極(ji):電(dian)極(ji)埋(mai)在鹽(yan)中，不接(jie)觸空氣，使用(yong)壽命較長。用(yong)這種電(dian)極(ji)的(de)爐膛容積利(li)用(yong)系數高，但(dan)電(dian)極(ji)拆卸較困難。兩(liang)種電(dian)極(ji)都可(ke)用(yong)碳鋼(gang)(gang)或耐熱鋼(gang)(gang)鍛成，也可(ke)鑄造。
