1. Elastic force balance method
Measured based on the elastic deformation characteristics of the elastic element. The elastic element is deformed by the measured pressure, and the elastic force generated by the elastic deformation is balanced with the measured pressure. The elastic force can be measured by measuring the displacement of the deformation of the elastic element. Such pressure gauges include spring tube pressure gauges, bellows pressure gauges, and membrane pressure gauges.
2. Gravity balance method
There are mainly piston type and liquid column type. Piston pressure gauge converts the measured pressure into the mass of the balance weight added to the piston for measurement. It has high measurement accuracy, wide measurement range, stable and reliable performance, and is generally used as a standard pressure detection instrument to verify other types. Pressure gauge. The liquid column pressure gauge is based on the principle of hydrostatics, which converts the measured pressure into the height of the liquid column for measurement. The most typical is the U-shaped pipe pressure gauge, which has a simple structure and intuitive reading.
3. Mechanical force balance method
The principle is to transform the measured pressure into a concentrated force, balance it with external force, and obtain the measured pressure by measuring the external force at equilibrium. The mechanical force balance method is more used in pressure or differential pressure transmitters, with higher accuracy, but complicated structure.
4. Physical property measurement method
Based on the principle that some physical characteristics of the pressure measuring element change under pressure, such as electrical pressure gauge, vibration frequency pressure gauge, optical fiber pressure gauge, integrated pressure gauge, etc.