Pressure transmitters are instruments used for pressure measurement of various media. The accuracy of pressure measurement depends to a large extent on the correct installation of the transmitter, measuring tube and pressure-taking parts. For flammable and explosive occasions, pneumatic and electric pressure transmitters with corresponding explosion-proof grades should be selected. For the measured medium that is easy to block, viscous, corrosive, and has a low vaporization point, a flanged pressure transmitter can be selected. Intelligent pressure transmitters should be selected when the measurement accuracy is high and the environmental conditions are harsh.
In some occasions, the electric pressure transmitter can be directly installed on the process pipeline without additional support. The condition for direct installation on the process pipeline is that the process temperature and the ambient temperature should meet the operating conditions of the transmitter. However, when installing pressure transmitters in some special places, the following requirements must be paid attention to:
- When measuring gas pressure, the pressure point should be in the upper half of the process pipeline.
- When measuring the liquid pressure, the pressure point should be within the range of 0°C~45°C between the lower half of the process pipeline and the horizontal centerline of the process pipeline.
- When measuring the steam pressure, take the pressure point within the range of 0°~45° between the upper and lower half of the process pipeline and the horizontal centerline of the process pipeline.
- The installation position of the pressure source component should be selected in the pipe section with stable flow of process medium.
- When the pressure source part and the temperature source part are on the same pipeline, the pressure source part should be installed on the upstream side of the temperature source part, and the end of the pressure source part should not exceed the inner wall of the process equipment and process pipeline.
- For the medium to be measured is high temperature, a condenser must be installed. The length of the condenser is determined according to the temperature and medium, and it is cooled to the acceptable range of the sensor.
- When measuring the pressure of turbid media with dust, solid particles or sediments on the vertical process pipeline, the source part should be installed inclined upward, and the angle with the horizontal line should be greater than 30 degrees, and the horizontal process pipeline should flow downstream The beam is installed at an acute angle.
- The installation location of the pressure transmitter should be well-lit, easy to operate and maintain, and should not be installed in places with vibration, humidity, high temperature, corrosiveness and strong magnetic field interference, otherwise it will seriously affect the measurement results and the life of the transmitter.
- The pressure transmitter should be installed as close as possible to the source part. The installation height of the transmitter for measuring low pressure should be consistent with the height of the pressure point, especially for measuring liquid media and condensable gas media.
- When measuring the pressure of gas medium, the installation position of the transmitter should be higher than the pressure point. When measuring the pressure of liquid or steam, the installation position of the transmitter should be lower than the pressure point. The purpose is to reduce the additional facilities for exhaust and liquid drainage. In addition to the installation method of the pressure transmitter directly on the process pipeline, it is usually a separate installation method. The column bracket can be made on site, and the U-shaped bolt can be used for clamping, or the wall plate bracket installation method can be adopted. No matter what kind of installation In this way, the pressure transmitter should be installed vertically, and the cable entry of the instrument junction box should not face upwards.