Installation of explosion-proof thermocouple, should pay attention to accurate temperature measurement, safety examination and maintenance is convenient, and does not affect the equipment operation and production operations. To meet the above requirements, in the choice of the installation site of the thermocouple and insertion depth should pay attention to the following points: 1, explosion-proof thermocouple with a protection casing with heat transfer and heat loss, in order to reduce the measurement error, thermocouple and thermocouple should have enough: (insert depth 1) For measurement of pipeline fluid temperature explosion-proof thermocouple, generally should be measuring end is inserted into the pipe ( Vertical or inclined installation) 。 As the current body of pipe diameter is 200 mm, the thermocouple insertion depth should choose 100 mm; ( 2) For high temperature and high pressure and high velocity of temperature measurement, Such as main steam temperature) , in order to reduce cases of fluid resistance and prevent cases break under the action of a fluid, can take protecting tube shallow inserted way or use hot thermocouple. Shallow inserted type thermocouple protection tube, its depth into the steam pipe should be no less than 75 mm; Heat sets the standard of thermocouple insertion depth is 100 mm; ( 3) If is need to measure the temperature of flue gas, although the flue is 4 m in diameter, thermocouple insertion depth of 1 m. ( 4) When measuring the original insertion depth of more than 1 m, shall be installed vertically, as far as possible or add racks and protect casing. 2, in order to make the measurement end of the thermocouple, and had good heat exchange between the measured medium, should be a reasonable choice of observation, try to avoid the valve, elbow and thermocouple pipeline and equipment near the corner of installations. Explosion-proof explosion-proof thermocouple in petroleum and chemical industry enterprise is widely applied in automatic control system, through the temperature sensor to control the temperature of the object parameters into electrical signals, to the digital display, recorder or adjust instrument, testing, adjusting and controlling of system. At the scene of the production of petrochemical enterprise is often accompanied by various kinds of flammable, explosive chemical gases, such as steam, if use normal thermocouple is not safe, easy to environment caused by gas explosion. On these occasions, therefore, must use flameproof thermocouple as the temperature sensor. This company produces the flameproof products are applicable to the thermocouple and isolation level for d Ⅱ BT4 or d Ⅱ CT4 range with explosive gas temperature classes is the dangerous situation.