Thermocouple and thermal resistance installation requirements
The installation of thermal resistance and thermocouple should pay attention to the accuracy of temperature measurement; safe and reliable and easy maintenance, and does not affect the equipment operation and production operations. To meet the following requirements, in the choice of thermocouple and thermal resistance of the installation site and insert the depth should pay attention to the following 2 points:
1, with protective sleeve thermocouple and thermal resistance with heat transfer and heat loss, in order to reduce the measurement error, thermocouple and thermal resistance should have sufficient insertion depth.
(1) When measuring the original insertion depth of more than 1m, should be installed as far as possible vertical, or the installation of support and protective sleeve.
(2) If you need to measure the temperature of the flue gas flue, although the flue diameter of 1000mm, thermocouple or thermal resistance can be inserted into the depth of 500mm.
(3) For thermocouples that measure the temperature of the center of the pipe, it is generally necessary to insert the measuring end into the center of the pipe (vertical or tilted). If the pipe diameter of the fluid to be measured is 100 mm, the thermocouple or thermal resistance Insertion depth should be selected 50 to 100 mm (should take into account the size of the mounting base or flange).
(4) For high temperature and high pressure and high temperature fluid temperature measurement (such as the main steam temperature), in order to reduce the resistance of the casing to the fluid and prevent the protection of the casing under the action of fluid fracture, Thermocouple thermocouple. The plug-in thermocouple protection sleeve, which is inserted into the main steam pipe depth should not be less than 75mm; thermocouple thermocouple standard insertion depth of 100mm.
2, in order to thermocouple and thermal resistance of the measuring end and the measured medium between the full heat exchange, should choose a reasonable measuring point position, try to avoid the valve, elbow and pipe and equipment near the dead end of the installation of thermocouple or Thermal resistance.
