What is the advantage of different types of thermocouple _ instrument

Type thermocouple temperature measurement principle is measured the change in temperature is directly measured by thermocouple resistance change, therefore, the wires of a thermocouple body such as a variety of wire resistance change will affect temperature measurement. Thermocouple is by the thermal components, wire, insulation materials, stainless steel casing combination solid body, its diameter is commonly phi - 2 Phi is 8 mm, achieve more xiaoke phi is 0. 25mm。 It has the following advantages: small volume, no internal air gap and thermal inertia, small measuring hysteresis; Good mechanical properties, resistance to vibration and impact resistant; Can bend, easy to install and use life is long. End thermocouple temperature sensing element resistance wire winding by special processing, close to the face in the thermometer. Compared with general axial thermocouple, it can reflect more correctly and quickly end face of the actual temperature being measured, is suitable for measuring temperature bearing and other parts of the face. Junction box flameproof thermocouple with special structure, its shell internal explosive mixed gas by sparks or electric arc affected explosion limit within the junction box, that wouldn't make production field explosion. Flameproof thermocouple can be used in the bla B3c level zone with explosion danger place temperature measurement. Anti-corrosion thermocouple using ptfe anti-corrosion material, as a whole case or two casing, also can be directly on the protecting tube for the anti-corrosion material handling, spraying, sintering and casing sealed three forms. Applicable to measure in alkali corrosive medium, the heat resistance of 250 ℃, fixed installation situation also can adopt the same ptfe material fixed screw, fixed flange ( Contact interface mass surface) Or set of thread, etc. A variety of installations, a variety of diameter, arbitrary choice. Heat set of thermocouple supporting special thermometer for coal-fired power units table. The use of international popular separate protection tube structure. Elastic pressure measuring element, add the maximum temperature of 650 ℃ high temperature platinum resistance. Commonly used in low temperature zone thermocouple is a kind of temperature detector. Thermocouple temperature measurement is based on the metal conductor resistance value increases with the increase of the temperature of the properties for temperature measurement. Its main characteristic is high accuracy, stable performance. The platinum thermocouple measuring accuracy is high, it is not only widely used in industrial temperature measurement, and is made into standard benchmark instrument. Thermocouples are mostly made of pure metal materials, the application is a lot of platinum and copper, in addition, now began to use the materials such as nickel, manganese and rhodium thermocouple. Metal thermocouple commonly used thermal material sort is more, the commonly used is a platinum wire. Industrial measurement with metal material in addition to the platinum wire, thermocouple as well as copper, nickel, iron, iron - Nickel, etc.