The thermometer is bimetallic. Main characteristics

Many heating systems and household and industrial installations use a bimetallic thermometer that shows the temperature change in a gaseous or liquid medium. It is a universal device. It can be installed in confined spaces, both indoors and outdoors. It is used in nuclear power plants, oil refineries, military ships, etc.

The bimetallic thermometer operates on the basis of the following physical law: "Different metals change or contract differently as the temperature of their environment changes." The sensitive element of the thermometer is a bimetallic spring (or plate), consisting of two different metals, pressed together. Since they have a different expansion coefficient, as the temperature of the medium rises or falls, they deform. The deformation of the metals causes the arrow of the thermometer to rotate and show the temperature on the scale.

The bimetallic thermometer consists of a chrome-plated steel body, a sensitive bimetallic element (spring or plate), enclosed in a brass thermo-balloon, dial and kinematic mechanism with an arrow. The dial and the arrow cover the glass. A conventional thermometer can show a temperature in the range of -70 ° C to + 600 ° C.

All bimetallic thermometers, depending on the mounting of the dial axis, are divided into two groups: basic and radial. The axis of the dial of the axial bimetallic thermometer is parallel to the axis of the thermoball. The radial bimetal thermometer differs from the axial thermometer in that its axis is located at the angle of 90 ° to the axis of the thermoball.

Classify the types of bimetallic thermometers can also be used for the purpose of the device, in the place of its work. Depending on the purpose, the thermometers are tubular and needle. Pipe thermometer bimetallic measures the temperature of the pipe in the heating system from its surface. Needle-shaped bimetallic thermometers measure temperature with a special probe-needle, immersed in the medium.

Depending on the place of use, the devices are divided into household and industrial bimetallic thermometers. The range of temperature measurement by household devices is much less than that of industrial bimetallic thermometers. When making household options, they take into account the conditions in which they will work.

Industrial bimetallic thermometers are manufactured both with highly specialized capabilities and with universal ones. They can work in any phase state and in a very wide temperature range.

A bimetallic thermometer is an excellent alternative to a liquid. Its disadvantages consist only in the fact that it is more expensive to manufacture and the duration of temperature measurement is more.

When purchasing a bimetallic thermometer, it is necessary to pay attention to the availability of a certificate of conformity and a passport. When working with the device, it is necessary to observe the temperature range specified in the thermometer's passport.