OPT series high temperature furnaces use double shell structure and intelligent temperature control of phase-shifted control. The furnaces consists of high purity alumina polycrystalline fiber brick. Its double layer between the furnace shell is equipped with air cooling system, which makes temperature cool and rise quickly. Unique touch screen system make the control more accurate and graphic interface more convenient. This series muffle furnace can be widely used in universities, research institutes, industrial and mining enterprises for high temperature sintering , materials sintering, composition analysis，quality testing and related heating treatment work.