The DCS reading for the differential pressure (saturated) steam flow meter is at its maximum when there are no users
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The differential pressure (saturated) steam flow meter shows the highest reading. Close all valves (including primary valves, secondary valves, and balance valves), and observe for one week; the DCS readings will always be zero ； After the gauge is properly adjusted, the DCS reading is 0; however, after 30–50 minutes the DCS shows a maximum value, and when the balance valve is opened, the phenomenon is the same as before. Checked: No leaks (tested with soapy water), no blockages (drainage has been performed). The balance valve has been replaced, and one EJA differential pressure transmitter has also been replaced; however, the problem persists. Note: The installation method for differential pressure flow meters is as follows: the pressure tapping ports are located above the flow meter (in this project, there are 12 such steam flow meters, and all of them display normal readings); the condensation tank is placed at the very top of the flow meter. The primary pressure tube enters from the outside of the condensation tank, while the secondary pressure tube exits from the bottom of the condensation tank and leads to the differential pressure transmitter located below it. Additionally: The primary valve on the positive pressure side is leaking, at about one drop per second. I believe it will not affect the measurement, because once the condensation tank is filled with water, a leak in the one-way valve will not impact the water level of the condensate in the tank. Dear sea friends, please analyze what could be the reason for the flow meter to show the maximum value! Thank you so much!
Given that the transmitter is confirmed to be correct, this situation occurs because the positive and negative pressure difference exceeds the transmitter’s range. In my opinion, there is still some obstruction; the pressure conduit isn’t completely blocked. It is likely that the actual flow rate is quite high. When the actual flow rate decreases, it is probable that the maximum value will no longer be displayed, and it may even show the minimum value instead.
Hey everyone, this flow meter operates at its maximum capacity even when there are no users – I really can’t figure it out! ! ! I hope all the friends here can help! ! !
"\"A new EJA differential pressure transmitter has been installed.\" Was the range of the transmitter modified?
The range has not been modified. Could it be a range issue? The differential pressure value is calculated by the flow meter manufacturer, and the operating conditions observed are essentially the same as those in the design
I seek advice from the experts! ! ! ! ! ! ! !
I agree with the view from the second floor. If there’s no smooth flow, then there should be no users; the traffic volume display should show the minimum value in that case. But when there are no users, it still shows the maximum value, which doesn’t make sense. Has the pipeline been checked to confirm that no steam is passing through it?
Has the water in the condensation tank been checked? Is it full? If this happens in summer, remove the insulation material. We encountered this issue in winter; we suspected that the heating strip was too hot. After removing the insulation, the heating strip was still powered on, and then everything worked normally. In summer, if the tank has just been emptied of waste, check whether the condensation tank is full, and also check whether there are any leaks in the root valve
Indeed, there are no users. Thank you for the guidance!
Yes, it’s possible that the liquid levels in the two condensation tanks are different. Another question: Under normal conditions, does leakage from the primary valve on the positive pressure side affect the measurements?
It will certainly affect the measurements, but in a situation like yours, it is likely not related much to the leakage measured under positive pressure. Under normal measurement conditions, the leakage flow rate measured under positive pressure will show as lower