Selection of Pressure Gauges for Electric Heating Thermal Oil Furnaces
Classification of pressure gauges, selection of pressure gauges, and installation and daily maintenance of pressure gauges.
1 Classification of Pressure Gauges
According to different conversion principles, pressure gauges can be roughly divided into four categories:
The first type is the liquid column manometer:
Based on the principle of hydrostatics, the measured pressure is expressed by the height of the liquid column. There are different structural forms, so they can be divided into U-tube manometers, single-tube manometers, etc. This type of manometer has a simple structure and is very convenient to use. However, due to factors such as the capillary action of the working fluid, density, and parallax, its accuracy can be greatly affected. Because its measurement range is relatively narrow, it is generally used to measure low pressure, pressure difference, or vacuum.
The second type is the elastic pressure gauge:
It converts the measured pressure through the displacement of the elastic element deformation, such as spring tube pressure gauges, diaphragm pressure gauges, and spring tube pressure gauges.
The third type is the electrical pressure gauge:
It converts the measured pressure into electrical quantities (such as voltage, current, frequency, etc.) of mechanical and electrical components for measurement, such as various pressure transmitters and pressure sensors.
The fourth type is the piston pressure gauge:
Based on the principle of hydraulic pressure balance, the measured pressure is balanced by the weight of the piston and the weight, and the pressure value is obtained. It is often used as a standard pressure measuring instrument for calibrating other pressure gauges, such as a piston pressure gauge.
