The maximum working temperature is up to 2000 ℃, and the unique heating wire design inside ensures that the crucible is heated evenly, and the steam source itself has more prominent service stability and life. The heat insulation design of multi-layer line contact tantalum cylinder greatly reduces the proportion of thermal radiation and increases the utilization rate of heat, which is the key guarantee to obtain extremely high temperature. The temperature of the crucible can be accurately measured by the improvement of the fixed mode of the thermocouple. The temperature stability can be increased to 0.1 ℃ by PID temperature control power supply