The thermocouple thermoelectric emfs growth over the course of measuring the temperature, the size of the thermoelectric potential and thermocouple temperature difference on both ends of the conductor material and, only has nothing to do with hot electrode length and diameter. By welding on both ends of the two different ingredients of conductor, form a loop, directly measuring WenDuan call work side, the terminal end is called the cold end, also known as the reference. When work end and reference end there is temperature difference, will produce thermal current in the circuit, connected to display instrument, the instrument will indicate the thermocouple thermoelectric emf generated by the corresponding temperature value. Thermocouple generally can measure 0 ~ 1300 ℃ within the scope of the gas, liquid and solid surface or internal temperature and steam. Thermocouple can form a complete set of digital instrument and record adjusting instruments, PLC and data terminal or computer use, as a new generation of temperature sensor, it can be widely used in metallurgy, petroleum, chemical, power, light industry, textile, food, national defense and scientific research and other departments. The structure principle of thermocouple is made up of a conductor, high insulation magnesium oxide, coat 1 cr18ni9ti stainless steel protecting tube, after many integrated control. Thermocouple products are mainly composed of terminal block, terminal and thermocouple basic structure, and with various mounting device. Thermocouple insulation type and hull type two kinds. Can bend, high pressure resistance, heat fast response time and strong and durable many advantages, such as it and industrial use, as measure temperature sensor, and usually display meter, recording meter and electronic regulator, at the same time, also can be used as a temperature sensing element. It can directly measure all kinds of production process from 0 ℃ ~ 800 ℃ in the scope of liquid, steam and gas medium, as well as the surface temperature of the solid. And compared to the thermocouple is flexible, high pressure resistance, thermal response time is short and strong and durable, etc. Thermocouple temperature measurement principle is based on thermoelectric effect. Connect the two different conductor or semiconductor into closed loops, when the two contacts in temperature is not at the same time, the circuit will produce thermoelectric potential, this kind of phenomenon called the thermoelectric effect, also known as the seebeck effect. Thermocouple as the temperature measurement sensor, usually with temperature transmitter, controller and display instrument, such as process control system, to directly measure or control in the production of a variety of 0 Fluid over a range of 1800 ℃, steam and gas medium and solid surface temperature. Thermocouple can bend, high pressure resistance, heat fast response time and strong and durable many advantages, such as it and industrial prefabricated thermocouple, as measure temperature sensor, and digital display meter, recording meter and electronic regulator usually used. Thermocouple calibration method of metallic melts fast thermocouple calibration method and device. The device is mainly composed of a can accommodate two measured accidentally the flat heated quartz tube end of coil, two with her being measured thermocouple and the corresponding temperature control of the same shape according to the output device. Calibration verification method: first use two thermocouple find the two calibration in this flat heating coil accidentally thermoelectric potential of the same point, replacing one of the calibration with checked accidentally accidentally, in the case of other conditions unchanged, after being checked my reading stability compared with the calibration my reading can be accidentally quantities are accurate. Characteristics: a, the device is composed of a flat heating coil, a pair of calibration of thermocouple and display output of temperature control device. B and verification method is to first two calibration thermocouple from relative insert on both ends of the heating coil, the hot end of thermocouple, thermocouple location in the heating coil made by changing the calibration two calibration of the thermocouple thermoelectric power, the same measured fast thermocouple to replace one of the calibration of thermocouple, read the thermoelectric potential value of measurement under the steady state and compare the calibration thermocouple thermoelectric potential can be measured quickly the accuracy of the thermocouple.