Question regarding the pressure measurement location for gases
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This post was last edited by A Entropy on 2021-11-25 at 09:44. Standard SH/T 3104-2013 provides instructions regarding the orientation for taking pressure readings of gases, as shown in Figures 1 and 2. As can be seen from Figure 1, when measuring gas, it is done within a 45° range on both the left and right sides above the pipeline. Figure 2 shows that the gas flows into the pressure transmitter after being drawn out; the pressure transmitter itself is located above the pipeline. In actual operations, situations like those shown in Figure 3 may occur. The pipeline is more than 2 meters above the 2nd-floor platform. There is a point on this pipeline where gas pressure is measured. In the diagram, the pressure measurement point is located on a horizontal line to the side of the pipeline; a pressure conduit runs downward from there, and the pressure transmitter is installed below this measurement point. In the approach shown in Figure 3, the location of the pressure tapping port and the installation position of the pressure transmitter are both different from those specified in the standards. The question is that this approach shown in the diagram differs from the standards, but whether it is also feasible in practice. Additionally, if it is necessary to follow the standard requirements, in cases where the height of the pipeline as shown in the diagram is relatively high above the platform or ground, and according to the standards it needs to be fixed above the pressure measurement point, how should it be fixed? Use a 3-meter-high support?
As can be seen from the diagram, it is best to place the pressure sensor for gases at the top, as there is a risk that condensation or other impurities in the liquid could affect the measurements; therefore, when it is installed at a lower position, there must be a drain outlet.
The second floor is the correct choice; it can also be installed below, and regular drainage is sufficient. If it tends to produce a large amount of condensate and is installed at the bottom, then carry out a relocation.
The specifications refer to pressure tapping points; you need to consider why he said that – it’s because he is concerned about impurities in the pipeline. If you place the pressure tapping point at the bottom, these impurities can easily enter the pressure conduit and then reach the instrument, affecting the measurement results. The transmitter can be placed on top or at the bottom; neither of these is a problem. If condensation occurs, insulation or heating can be used to prevent it. Another option is to use a condensate tank filled with water, which prevents condensation from forming and ensures that errors are not caused by it. Once the tank is filled with water, there will be no issues. The installation of instruments should be done in the most convenient way possible; ease of maintenance is what matters most.
Thank you for your guidance, senior.:handshake
The pressure guide tube also has a variable diameter; it’s amazing
It was processed this way to prevent deformation during transportation from the Yangtze River Delta to Karamay