Seek expert help to resolve difficulties with V-cone flow meters.
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This post was last edited by Muya_NZGR on 2018-10-15 10:08: V-cone flow meter, medium saturated steam. After one day, it is necessary to bleed off the vapor; once that is done, the flow rate returns to normal. If no bleeding is performed, the flow rate remains abnormal, and the reading displayed by the EJA differential pressure transmitter gradually decreases, dropping to 0.1%. It’s much lower than the actual traffic volume. How to solve this kind of problem?
Where does the exhaust gas come from? Is there air in the flowmeter pipeline or in the pressure guide tube? If it is inside the pipeline, it is likely that there is condensation at the flow meter, which causes the differential pressure of the instrument to decrease. If it is the air from the pressure guiding tube, it is due to inconsistent condensation amounts on the positive and negative pressure sides, which results in a low differential pressure.
It’s necessary to go to the site to take a panoramic photo or draw a schematic diagram, clearly describing the spatial relationships among all the components related to pressure measurement. Only then can the dog figure out what’s going on. The dog’s eyes were very bright. .
How to solve the problem with condensate?
It is recommended that the original poster clarify the question further; the issues raised by the people above are all related to fault diagnosis.
What is the steam temperature? How are the transmitter and V-cone installed? Is the transmitter located at the top or bottom of the pipeline? It’s likely a fault caused by improper installation, which led to an imbalance between the vapor and liquid phases
It seems you need to thoroughly overhaul the sampling pipeline: ensure that the condensate level remains constant at all times
This post was last edited by MuYa_NZGR on 2018-10-17 at 13:50. The maximum temperature is 192 degrees; the transmitter is located at the bottom of the pipeline, so there should be no issues with this installation, as I installed it according to the drawings. I think it might be related to the boiler burning intermittently, as it only runs for two hours at fixed times throughout the day, then stops, and starts again the next day.
Could resetting the zero point of the differential pressure transmitter also solve the problem?
It’s best not to do this. Of course, when it’s difficult to resolve the issue, an appropriate value can be adjusted; by checking the situation with and without flow as well as changes in flow, it can be determined whether a final stable state exists. In other words, even if the liquid levels of the condensate on both sides are not identical, the difference between those levels eventually stabilizes. It is indeed possible to make measurements using such adjustments, but the accuracy needs to be analyzed and assessed; with good luck, the results can be comparable to those obtained under normal conditions.