Digital Temperature Gauges

The Gas Filled Dial Thermometer consists of a stem, capillary, and bourdon tube in a case. These parts are connected to form a unit. The complete measuring system is filled with an inert gas such as nitrogen, as standard,under pressure. A temperature change causes the internal pressure and volume in the stem to change. The deflection of the bourdon tube thus caused is transmitted to the pointer by a movement. A bimetallic element is fitted in between the movement and bourdon tube to compensate for fluctuations of ambient temperature at the case.