Precautions for the Use of Digital Pressure Gauges and Vacuum Pressure Gauges

Ⅰ. What are the precautions for the use of digital pressure gauges?

Pressure gauges are commonly used measuring instruments and are widely used in various fields. It can intuitively display the pressure changes in each process link, gain insight into the formation of product or medium process conditions, monitor the safety trend during production and operation, and establish a fast and reliable safety guarantee through automatic chains or sensing devices, which plays an important role in preventing accidents and ensuring personal and property safety.

1. The range of the digital pressure gauge installed on the boiler and pressure vessel should be compatible with the working pressure of the equipment. The range of the digital pressure gauge is generally 1-3 times the working pressure of the equipment, take 2 times.

2. The accuracy of the working digital pressure gauge is expressed as a percentage of the allowable error of the limit value of the dial. Accuracy is usually marked on a dial. When choosing a digital pressure gauge, its accuracy should be determined according to the pressure level of the equipment and the actual work needs.

3. Dial diameter In order for the operator to see the pressure value accurately, the dial diameter of the digital pressure gauge should not be too small. If the digital pressure gauge is installed higher or farther from the column, the dial diameter should be increased.

4. If the medium measured by the digital pressure gauge is corrosive, different elastic element materials must be selected according to the specific temperature, concentration and other parameters of the corrosive medium, otherwise the expected purpose will not be achieved.

Ⅱ. Precautions when using vacuum pressure gauges

1. The meter must be vertical: use a 17mm wrench to tighten it during installation, and the case should not be twisted; collisions should be avoided during transportation;

2. The instrument should be used in the ambient temperature of -25~55℃;

3. The vibration frequency of the working environment is less than 25Hz, and the amplitude is not more than 1mm;

4. In use, due to the high ambient temperature, the indication value of the instrument does not return to zero or the indication value is out of tolerance, the sealing rubber plug on the upper part of the case can be cut off to make the inner cavity of the instrument communicate with the atmosphere;

5. The use range of the vacuum pressure gauge should be between 1/3 and 2/3 of the upper limit;

6. When measuring corrosive media, media that may crystallize, and media with high viscosity, an isolation device should be added;

7. The instrument should be checked frequently (at least once every three months), and if any fault is found, it should be repaired in time;

8. Instruments for measuring corrosive media should be used, and the requirements should be specified when ordering.

The vacuum pressure gauge is an indispensable test instrument when repairing refrigeration equipment. It can measure high pressure of 1.5MPa and vacuum degree of -0.1MPa. The commonly used vacuum pressure gauge has a total of two circles of numerical scales on the dial from the inside to the outside, indicating the pressure value.