For the installation of bimetallic thermometers, attention should be paid to ensuring accurate temperature measurement, safety, ease of maintenance, and not affecting equipment operation and production. To meet the above requirements, the following points should be noted when selecting the installation location and insertion depth of the thermistor:

(1) In order to ensure sufficient heat exchange between the measuring end of the thermistor and the measured medium, the position of the measuring point should be selected reasonably, and the installation of the thermistor near the dead corners of valves, elbows, pipelines, and equipment should be avoided as much as possible. (2) Thermistors with protective sleeves suffer from heat transfer and dissipation losses. To reduce measurement errors, thermocouples and thermistors should have sufficient insertion depth:

a、 For measuring the temperature of the fluid at the center of the pipeline, the measuring end of the thermistor should generally be inserted into the center of the pipeline (vertically or obliquely installed). If the diameter of the tested fluid pipeline is 200 millimeters, the insertion depth of the thermistor should be selected as 100 millimeters;

b、 For temperature measurement of high temperature, high pressure, and high-speed fluids (such as main steam temperature), in order to reduce the resistance of the protective sleeve to the fluid and prevent the protective sleeve from breaking under the action of the fluid, shallow insertion of the protective tube or the use of a hot sleeve thermistor can be adopted. The shallow insertion type thermal resistance protective sleeve should be inserted into the main steam pipeline at a depth of not less than 75mm; the standard insertion depth for hot sleeve thermal resistance is 100mm;

c、 If it is necessary to measure the temperature of the flue gas in the flue, although the diameter of the flue is 4m, the insertion depth of the thermistor is 1m;

d、 When the insertion depth of the measuring element exceeds 1m, it should be installed vertically as much as possible, or support frames and protective sleeves should be added.