The temperature gauge is one of the most widely used equipment for measuring the temperature of fluids, which is installed and operated on pipelines or tanks. The value taken by the temperature gauge or thermometer can be displayed locally.
What is temperature?
Temperature is a sign of the average speed of the molecules that make up a body. ( Temperature gauge ) In fact, it can be said that temperature is a quantity that, due to the difference between two objects connected to each other or two points of the same object, causes the spontaneous transfer of heat from the object with higher temperature to the object with lower temperature.
In simpler terms, it can be defined as temperature is a measure of hotness or coldness of objects. When we give heat to a body, its molecular movement and internal kinetic energy increase, which is manifested as an increase in temperature.
On the contrary, taking heat from the body causes the speed of molecules and the temperature of the body to decrease. According to the molecular kinetic theory, if the energy of an object continues to decrease to zero, the molecular movement stops completely and its temperature reaches absolute zero, i.e. -273.15 degrees.
Temperature measurement in the industry is one of the most important measurement parameters. Because in industrial processes, the temperature of fluids flowing in pipelines and tanks must be continuously and permanently measured and controlled.
Types of temperature gauges
Dial thermometers or temperature gauges are analog displays of the temperature of a specific point in the process, which are divided into the following two categories in terms of performance:
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Non-metal thermometers
The function of this thermometer is based on the reduction or increase in the length of a metal due to temperature changes. 2 metals that have different longitudinal expansion coefficients are welded to each other and connected to a fixed point. Temperature changes cause changes in the length of this metal. One of the metals responds better to the increase in temperature and takes the other metal with it, and the second metal responds better to the decrease in temperature and takes the first metal with it.
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GAS ACTUATED thermometers
This type of thermometer works by using the change in gas pressure caused by the temperature change, that is, the change in the temperature of the thermal sensor causes the change in the pressure of the filled gas, and thus the temperature is displayed by a needle pressure gauge that is calibrated based on the temperature. It will be given.
The filled gas must be an inert gas such as nitrogen or helium. The most important use of filled thermometers is when the temperature probe is more than 1 meter away from the hand display and access to the heat source is far away or inaccessible. This model of temperature gauges is called a capillary temperature gauge or trailing temperature gauge, which can be between 1 and 5 meters long.
Temperature gauge manufacturers
Various manufacturers in the world produce temperature gauges or thermometers, the most important of which are Vika, Ashcroft, Pickens, Chela, etc.