Shanghai Automation pressure gauge selection requirements

The selection of pressure gauge of Shanghai Automation mainly includes instrument type, range, accuracy and sensitivity, size and whether it also needs to be transmitted and other functions, such as indicating, recording, vibration alarm, control, etc. The selection basis is as follows:

(1) Must meet the requirements of the process production process, including range and accuracy;

(2) must consider the nature of the measured medium, such as temperature, pressure, viscosity, corrosion, inflammable and explosive degree;

(3) It is necessary to pay attention to the on-site environmental conditions when the instrument is installed and used, such as ambient temperature, electromagnetic field, vibration, etc.

In the selection of the range, it should be noted that the normal pressure should be at the upper limit of the scale for stable conditions; For pulsating pressure, the normal pressure should be at the upper limit of the scale; For high pressure, the normal pressure shall be below the upper limit of the scale.

From the properties of the tested medium, the corrosion resistant diaphragm pressure gauge is selected for the strong corrosive medium or the contact part of the medium with corrosion resistant materials; Diaphragm pressure gauge is used for viscous, crystalline and easily blocked media. According to the classification of explosive dangerous medium choose pressure-proof explosion-proof or intrinsically safe explosion-proof grid; Measuring oxygen, ammonia, hydrogen, acetylene, hydrogen sulfide and other media should choose a special pressure instrument.

From the point of view of the output signal requirements of the instrument, for only the need to observe the pressure change, can choose the spring tube or u-shaped liquid column as a direct indication of the instrument; For the need to use the instrument environment, for the temperature is particularly high or low environment, should choose the temperature coefficient of small sensitive elements; For explosive environment, in the use of electrical sensors, capacitive pressure sensors, etc. For the case of detecting rapidly changing pressure signals, electrical = test pressure detection instruments, such as diffused silicon pressure sensors, should be selected. From the use of the instrument environment, for particularly high or low temperature environment, should choose the temperature coefficient of small sensitive elements; For explosive environment, in the use of electrical pressure gauges have their own characteristics and scope of adaptation. After the pressure gauge is selected, it should be installed correctly to avoid measurement errors caused by improper installation. When installing the pressure gauge, you should choose the safety explosion-proof pressure gauge.

Each pressure gauge has its own characteristics and scope of adaptation. After the pressure gauge is selected, it should be installed correctly to avoid measurement errors caused by improper installation. The installation of the pressure gauge must be carried out in strict accordance with the operation manual of the pressure gauge.