TUBE HEATER DEVICE

PROBLEM TO BE SOLVED: To provide a tube heater device capable of sharply reducing the manufacturing cost with extremely simple constitution, easy in maintenance and control and improving reliability in pinhole detecting accuracy. SOLUTION: This tube heater device arranged in a chemical tank 10 together with a tube by arranging a heat source 14 heated being connected to a power source 24 in a sealed tube 16, is composed of a conductive sensor 30 arranged in the sealed tube 16 in a state of opening a part of a closed circuit, a switch 26 arranged between the power source 24 and the heat source 14 in the sealed tube 16 and a controller 32 for opening the switch 26 by receiving an electrically continuing signal of the conductive sensor 30 by chemicals 12 flowing in the sealing tube 16. By arranging the conductive sensor in the tube to be electrically conducted with the chemicals flowing in the sealed tube as a medium, the detecting accuracy is improved, and the constitution is simplified, and the manufacturing cost is kept low.