Problems with differential pressure level gauges
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The drum differential pressure level gauge has three indicators; currently, two of them show 76%, while the third shows 86%. At first, it was thought that the pressure transfer tubes were blocked, but nothing changed after clearing the blockages. Water was then added to the isolation tank, and the gauge still indicated around 76%; thereafter, its reading increased at a rate of 0.01% per second, but it ultimately stayed at 86%. No reason can be found; solve it.
Has this problem been around all along, or did it appear recently? Has the transmitter zero point been checked? Will it then stay constant at 86%?
There seems to be some zero drift; just perform an atmospheric zeroing. If that doesn’t work, refill the liquid
First, shut down the transmitter and check the zero point； If the zero point is correct and it can be disassembled, calibrate the transmitter ； There’s still no problem; it’s probably an issue with the balance container or the piping.
Open the balance valve and check the zero point first. Problems with differential pressure are usually due to zero drift, but I think in your case someone must have done something to the pressure guiding tubes or isolation valves
With three identical watches, the substitution method can be used to try out different options, and it’s easy to determine where the problem lies
The density differences at various points differ from the design values! We’ve encountered this problem too; it seems like this reason is quite plausible! After all, it is a differential pressure level gauge……
The gas-phase pressure guiding tube is leaking. Check it carefully; it’s not due to drifting nor any density issue.
It seems I still need to remove the insulation material; it’s quite troublesome.
I think it’s caused by the density; otherwise, why would the indicator be normal right after the isolation fluid was poured in?
1. If the inspection of the transmitter and parameter settings shows no issues (and it’s likely there are none), fully open the pressure tap valve on the steam drum to see if this improves the situation. Has the pressure tap valve been used for plugging leaks under pressure? What material is the gasket made of? 2. Turn off the pressure tap valve of the drum, and test the balance of the container separately at 50% and 100% capacity; maintain the system at each setting for a certain period of time, such as 1 hour, to check whether the liquid level is within the acceptable range and whether it remains stable. As for how to achieve and determine whether the water column is at 50%, figure it out yourself. 3. If there are still issues with the aforementioned test, it is recommended to replace the pressure valve with a gate valve.