I would like advice on selecting the pipeline pressure rating and the range of the local pressure gauge
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For the pump outlet pipe, the pressure inside the pipe is 1.23, the pressure rating of the pipe is PN16, and the temperature ranges from 50 to 60. An on-site pressure gauge should be used, and its range should be selected according to the specifications – it should be between 1/3 and 1/2. Therefore, a range of 0–2.5 is acceptable. The flange for the pressure gauge should then be of PN25 grade. However, this presents a problem, as the pressure rating of the pipe is only PN16; isn’t the flange grade too high? Alternatively, the range of the pressure gauge could be set at 0–1.6
The range of the pressure gauge should allow selection from 0 to 1.6
This post was last edited by ylb913 on 2016-8-24 at 13:44. It’s normal for instrument accessories to have a high pressure rating; take the GZ1/2 nozzles for example – those I’ve seen have a pressure rating of at least 160 kg/cm2. The needle valve in front of the pressure gauge is also………
The range depends on the process; it’s completely fine to use flanges of the PN25 grade. There are many instruments that use both PN25 and PN16, so it doesn’t matter. In your case, if the pressure fluctuations in the pipeline are not significant, a range of 0-1.6 is sufficient.
In my opinion, the range should be chosen based on the process parameters, while the flange class should be selected according to the pipeline class. Choosing a range of 0–2.5 ensures that the gauge pointer falls between 1/3 and 1/2 of its scale, which helps maintain accuracy in measuring pulsating pressures. For flange connections, PN16 is sufficient, as not only the pressure gauge but also other flanges on the pipes are of PN16 standard; this ensures that the flange of the pressure gauge is less likely to experience problems first.
For the pump outlet, a range of 0-2.5 is definitely more suitable. It’s also necessary to fill it with oil to reduce vibration; a flange of PN16 will work fine. Gauge manufacturers produce such instruments~
2.5, is it even necessary to ask? Choose a vibration-resistant pressure gauge; if the medium is clean, do not opt for one with flanges.
This post was last edited by hfrs on 2016-8-25 at 23:39. Additionally, choosing PN16 for your pipeline pressure is also a problem; the maximum allowable operating pressure is 13.4 bar, which is too low. If I had to make a choice, I would opt for at least PN25. Are you sure it’s 1.26 MPa, not KG/CM2?
Seismic resistance is a must; the pressure rating can be chosen based on your preferences – either one will work. A higher pressure rating makes the instrument more durable, while a lower one provides greater accuracy
:):):):):):):)
The operating pressure is within the PN16 range, and the pipe grade should also be PN16; therefore, it’s fine to choose a flange of PN16. A range of 2.5 represents the maximum value, and sometimes fluctuations in pressure occur during the initial testing phase, but such fluctuations do not cause the pressure gauge to exceed its range.