Issues regarding the liquid level adjustment of liquid ammonia storage tanks
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The liquid level in the liquid ammonia storage tank is measured using a magnetic flap level gauge and a differential pressure transmitter with a capillary. During today’s individual testing, water was poured into the tank, and it was found that there was a discrepancy between the reading shown by the magnetic flap level gauge and that shown by the transmitter. For example: the magnetic flap level indicator shows 1.3 m, while the differential pressure transmitter shows 1.1 m – why is there a difference of 200 mm? I’m completely puzzled and seek advice from those who are more knowledgeable.
It’s useless telling this to a layperson. Based on the differential pressure transmitter.
The magnetic flap also has an installation height; adjusting it will do
What does the installation height of the magnetic flap mean? The center distances between the upper and lower flanges of the differential pressure transmitter and the magnetic flap level gauge are the same
It’s related to density, right? ? The reply is too short; adding a word to meet the length requirement: dizzy:
This post was last edited by ylb913 on 2015-11-8 07:56. At 25 degrees, the specific gravity of liquid ammonia is 0.6. The specific gravity of water is 1; for your magnetic flap, it is 1.3 meters. For a double flange design, it should be 1.3*0.6=0.78 meters. Of course, the degree to which the float of the magnetic flip switch is lifted in liquids of different densities also varies; the higher the density of the medium, the higher the position indicated by the magnetic flip switch, but this variation is minimal as long as it can remain afloat. Because yours hasn’t settled yet.
I’m running a trial run now; I’m just adding water, not liquid ammonia. Why is it 1.3*0.6?
The density of water is greater than that of liquid ammonia; the float in your magnetic flip switch is designed for use with liquid ammonia. When the float is in water, the part of it that is above the surface becomes longer, which results in a higher reading on the magnetic flip switch
The differential pressure transmitter is also set according to the density of water; although the magnetic flap is calibrated based on the density of liquid ammonia, when water is present, the float inside rises and falls accordingly according to the density of water. Logically speaking, the liquid level corresponding to the differential pressure transmitter and the magnetic flap gauge should not differ significantly on-site; a difference of 200 mm is quite substantial.
For the same medium, when the liquid level is low, for example at 1 meter, adjust the double flanges so that they are aligned with the flip plate, then continue to add water and check whether other points can also be aligned.
I’m not sure about this; there’s a liquid level gauge with remote transmission available for magnetic flip-type devices – I wonder if it’s the same thing