The drum liquid level fluctuates severely; how can this be addressed from an instrumentation perspective?
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The drum liquid level fluctuates severely; how can this be addressed from an instrumentation perspective? It has been adjusted manually; can this problem be solved by replacing the gauge? 2206
This post was last edited by tiger2010 on 2022-12-7 07:00. In the video, what is used for transmitting the liquid level signal from the float level gauge – a reed switch or a magnetostrictive sensor? There are two liquid level transmitters in the video; which one corresponds to the liquid level trend shown in the image?
At the site, one is magnetostrictive and the other is differential pressure; the fluctuation trends of the two level gauges are the same
For the three-interaction control of the steam drum, attention must first be paid to water feed, liquid level, and steam production rates; manual control will certainly lag behind three-interaction control. Additionally, when selecting a water supply valve, its linearity must also be taken into account, as well as whether the valve diameter is sufficient to meet the water supply requirements and to enable stable level control.
Oh, if you just want to reduce the fluctuations, you can turn down the valve for the liquid phase to the 1/3–1/2 position and increase the damping of the instruments slightly to see the effect
This is clearly due to fluctuations in the water level inside the drum; stabilize the water inflow and reduce the opening degree of the magnetic flap root valve
Since you asked from the perspective of the instruments, I’ll give some suggestions: reduce the water valve at the bottom of the magnetic flap by one-half, and set the filtering time on the DCS control panel to 2 seconds. One of the magnetic flap differential pressure level gauges has been replaced, with the damping time increased slightly.
If it is indeed fluctuations in the water level inside the drum, doing this only provides a temporary solution rather than addressing the root cause.
The performance of the instruments reflects the real-time changes in operating conditions quite well. In my opinion, it is not very safe to use closing valves as a way to address these fluctuations, as there may be delays in the changes in liquid level
It’s better to have a genuine reaction! What about safety?