The differential pressure level gauge is inaccurate; help!
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Both the mechanical level gauge and the electronic transmitter level gauge at this site are giving inaccurate readings, and the levels indicated by both are quite similar to each other; they are far lower than the actual level! Now, the situation of a liquid level of 0 occurs frequently! When there is no accurate measurement, the value is always lower than the actual one. I would like to ask whether a differential pressure transmitter requires a balance valve? On this site, the balance valve is installed on the mechanical watch and is for common use. Now, if I want to cut off the mechanical level gauge and only activate the circuit for the transmitter, then it will no longer be possible to use the balance valve! The function of a balance valve is to prevent the sensitive components inside from being subjected to excessive pressure spikes. I would like to ask whether an electronic differential pressure transmitter also requires a balance valve? ? ? Many potential leak points were checked and none showed any problems. The data obtained from both detectors was inaccurate, and the same was true for the liquid level readings. Could there be other issues causing this? ? ? ? One of the abnormal situations is that when the liquid level is at 0, as long as unloading to equalize pressure begins, the liquid level will gradually rise again once the pressure in the storage tank drops.
How can one determine that the liquid level display is lower than the actual value, and can it be confirmed that there are no issues with the internal piping? Ensure that there are no leaks in the external pipelines, and that the balance valve has no internal leaks. Any issues with the pipelines related to the level gauge will be reflected on the gauge, giving the customer the impression that the gauge is broken. If it’s the level gauge that’s broken, then it’s easy to fix; it’s these uncertain factors that are really frustrating.
I sell mechanical ones, but differential pressure transmitters probably also require a balance valve for zero-point calibration. What is the capacity of this tank, and what liquid is it used to hold?
Hello, the pipeline connections outside have been checked numerous times already. . . There is no leakage issue, unless there is a leak inside the components. Basically, we create a liquid level schedule; when the liquid level reaches around 10 tons, it shows as 0. Both gauges read 0 at that point. After the tank truck has unloaded its load (19.5 tons), the displayed liquid level still does not exceed 20 tons. The tank has a capacity of 60 cubic meters. Yesterday, while cleaning the pipeline of the level gauge, it was found that the pressure gauge at the other end was leaking oil. . . The pressure gauge on the storage tank is an oil-proof gauge, while the one on the LNG skid is a shock-absorbing gauge. . . It seems like there’s quite a serious leak in the pipeline. It has now been replaced with an oil prohibition gauge, and the oil has been purged. I would like to ask whether an internal oil leak is causing the inaccuracies in the level gauge I’ve been wondering: if two level gauges are both inaccurate, and the amount of inaccuracy is the same in both cases, can we rule out a problem with the level gauges themselves? Could the issue lie in the piping, or perhaps in the oil leakage problem that was detected yesterday? Thank you
Was the level gauge on your tank like this from the beginning, or did the problem arise after some time? The situation is too complicated, and I don’t have any good suggestions either. I hope you can figure out the reason and share it with me so that I can learn from it as well.
It has been operating stably for over a year, but it stopped working this year! The error values are getting larger and larger. Additionally, the pipeline that carries the gas phase from our storage tank to the pump skid is quite long; could exposure to sunlight affect changes in internal pressure? In mechanical level gauges, the outlet for the gas-liquid mixture in the storage tank is about half a meter away, while the electronic pressure transmitter is approximately ten meters away (referring to the length of the pipeline). The total two-phase outlet of the pipeline is shared and interactive; considering how hot it is in summer, does sunlight have an effect on the pressure inside? Can this situation occur when both pressures are equal due to exposure to the sun? I’m at a loss now; I’ve considered every possible scenario that came to mind. . . . . . . .
Lighting should not have such a significant impact, and it shouldn’t affect both tanks at the same time. Have you contacted the manufacturer who sold you the storage tanks? What do they say?
If the issues with the instrument itself are ruled out, then it’s likely that the medium density parameter provided by the process engineering team to the instrumentation department was incorrect; it’s necessary to check whether there is any difference between the density of the medium indicated in the selection table and the actual density of the medium in use on site
The pressure gauge on the other end was purged; it was that pressure gauge which was leaking oil before, and now the readings are normal! I just can’t figure it out: with the two weather tubes separated from each other, if there’s oil leakage in the lower one, how could that affect the level gauge on the storage tank? Oil cannot fly upward against gravity. . . . .