Regarding the installation location of the pressure transmitter.
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Measure the pressure in the flue gas duct of the rotary kiln; the flue gas is dry. The pipeline is at a height of about ten meters above the ground. I want to connect the pressure transmitter to the ground via pressure tapping pipes; will this cause measurement errors?
No, air has no significant impact; go ahead and deal with him
Okay, thank you. Then I’ll deal with it.
SH/T 3104-2013 Code for Installation and Design of Instrumentation in Petrochemical Industries: Pressure guiding pipes should be as short as possible; the length of Pipe-type pressure guiding pipes should not exceed 15 m, while the length of Tube-type pressure guiding pipes should not exceed 12 m. Note: The medium under test is a gas; when the pressure remains constant, the pressure at the gauge point is the same as that at the pressure sampling point. When pressure changes, due to the compressibility of gas, the gauge pressure does not change immediately; its change is determined by the volume of gas in the pressure guiding tube. The larger the volume of gas in the pressure guide tube, the slower the change in the gauge pressure. In short, as long as the manufacturing process is acceptable and one doesn’t take any responsibility, it’s fine no matter what.
The rotary kiln should be under slight negative pressure; since you are far away, it will be difficult to make measurements, and the response speed will not be sufficient.
In this case, use a direct installation and keep the pressure introduction pipe as short as possible. There is still construction material left, and little maintenance will be needed in the future. By making it this long, dust might get into the pressure introduction tube and cause blockages, which would be difficult to deal with
It is recommended to keep it as close as possible to avoid signal transmission delays! Furthermore, due to the long transmission distance, it is highly affected by external temperatures; especially during cold seasons, this can result in a lower pressure reading
It’s over 10 meters tall; there’s no need to lower it – just install it directly, and the signal can be sent to the control room. Installing pressure tap pipes requires tubes, which also need to be secured, and it can lead to signal latency. The error increases. There’s no reason to do that.
Connect a purge air line to the pressure tap, use reverse blowing; if the gauge gives inaccurate readings, turn it on and blow to clear it