我所的25kW单相中温盐浴炉，1978年将其电极由插入式改成侧理式后，升温时间由原来的4h缩短到2h，节能约30％左右。但该炉炉膛当时是用高铝耐火砖所砌，电极是侧理式，在长期的生产使用过程中，由于炉膛的耐火砖与金属电极的膨胀系数不同，在升温或冷却过程中内外热胀冷缩不一 My 25kW single-phase medium-temperature salt bath furnace, in 1978 the electrode changed from plug-type side conditioning, the heating time from the original 4h shortened to 2h, about 30% energy saving. However, the furnace was built with high alumina refractory bricks at the time, the electrodes are side-type, in the long-term production and use process, due to the furnace refractory bricks and metal electrodes of different expansion coefficient, heating or cooling during internal and external thermal expansion Cold shrink different