The use of mercury thermometer

The thermometer, it is the floorboard of the temperature measuring instrument, can accurate judgment and measuring temperature. Use of solid, liquid and gas is influenced by temperature and heat bilges cold shrink phenomenon such as the basis for design. With kerosene thermometer, alcohol thermometer, mercury thermometer, gas thermometer, resistance thermometer, thermocouple thermometer, radiation thermometer and light thermometer, bimetallic thermometer and so on and so on many kinds of types for us to choose, but must pay attention to the correct method of use, understand the characteristic of the thermometer, facilitate better use of it. Using mercury temperature time, first to see its range ( Measuring range), Minimum degree value, and then see it, that is, the value of the each represents a small grid. To select the appropriate thermometer to measure the temperature of the object to be tested. When measuring the vacuole of the thermometer should contact with fully object to be tested, and the glass bulb without touching the side or bottom of the object to be tested; Thermometer readings, don't leave the object under test, and the line of sight of the eyes should h flat with a thermometer. Before the use should check ( More than standard liquid temperature comparison method may be used for calibration or more advanced precision thermometer) 。 Not allowed to use the temperature more than the thermometer of the measured value of the largest scale value. Thermometer have thermal inertia, after should reach a steady state in thermometer readings. Reading should be in the highest temperature on convex curved surface tangent to read, looking directly at them. 4. Should not be used as a stir bar. Mercury thermometer should be measured working medium with vertical or inclined shaped the direction of flow. Cold repair method: put thermometer temperature bag into the dry ice and alcohol mixture ( Temperature shall not exceed - 38℃) Cold, all make the mercury in the capillary contraction at the temperature measurement in the package. Hot fix method: insert the thermometer slow temperature slightly higher than the upper limit in the constant temperature trough, the mercury broken part and the mercury column, and then slowly remove the thermometer and cooling to room temperature in the air.