The correct choice of the pressure gauge
The correct selection of pressure gauges including pressure gauge type, range, accuracy and sensitivity, size and the need for transmission and other functions, such as indicating, recording, control, alarm and so on.
The main basis for selection of pressure gauges:
1. The requirements for measurement of process production, including range and accuracy. In the case of a static test (or slow change), the maximum value of the pressure measured is two thirds of the full scale of the pressure gauge. In the case of fluctuating pressure, the maximum value of pressure measured is one half of the full scale.
The accuracy rating of commonly used pressure gauges is 0.05, 0.1, 0.25, 0.4, 1.0, 1.5 and 2.5, and it should be selected from the accuracy of production process and economic angle. The maximum permissible error of the meter is the product of the range of the pressure gauge and the percentage of accuracy. If the error value exceeds the accuracy of the process requirement, the pressure gauge with a high degree of accuracy will be replaced.
2. The properties of the measured medium, such as state (gas, liquid), temperature, viscosity, corrosion, degree of pollution, flammability and explosive degree and so on. For example, oxygen table and acetylene watch, with the "oil - forbidden" sign, the corrosion pressure gauge for special medium, high temperature pressure gauge, diaphragm pressure gauge and so on.
3. Environmental conditions, such as ambient temperature, corrosion, vibration, humidity and so on. Such as shockproof pressure gauges for vibration environment condition.
4. Suitable for observation. According to the location and illumination of the instrument, the instrument with different diameter (shape, size) is selected.