Electrothermic tube

The utility model relates to an electric heating tube, which comprises an outer shell and a heater which is composed of a fine quartz tube and a resistance wire. The outer shell is a quartz tube, and an opening is arranged on one end of the outer shell. The resistance wire winds around the outer wall of the fine quartz tube after the resistance wire penetrates through the quartz tube. The outer shell is sheathed on the heater. After magnesite is filled in the fine quartz tube and between the fine quartz tube and the outer shell, the open end of the outer shell is sealed by silicon adhesive. Both ends of the resistance wire respectively extend out of a silicon adhesive layer. The utility model is suitable for the installation in various heating devices, with the advantaged of corrosion resistance property, no electric leakage, and long service life.