Migration of double-flange differential pressure transmitters
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Once the double-flange differential pressure transmitter (with silicone oil-filled capillaries) is installed on the equipment, can it be relocated? How exactly should this be done using 475? There are two types: one where the transmitter is below the lower flange, and another where it is between the lower and upper flanges. I would appreciate some guidance from those with more experience; thank you.
In the case of a double-flange level gauge, it is independent of the installation location of the transmitter. The simplest approach is to, after the gauge is installed, open the manual valves on the upper and lower flanges if the tank is empty, and check what value is displayed on the transmitter’s gauge. If the displayed value is -A and the range of liquid level variation is B, then the range you should set is from -A to B-A
If you’re an amateur, then don’t work with instruments. Those on the second and third floors are also amateurs; how can transmitters not have specific requirements regarding their placement? Transmitters should generally be installed under double flanges; other locations can be considered incorrect.
Many of our company’s double-flange level gauge transmitters are installed in intermediate positions! It’s been in use for many years!
What was said on the second floor is generally correct. However, the installation location of the gauge head has nothing to do with the medium inside the tank, but it is related to the pressure within the tank. If it is positive pressure, it is recommended to install the gauge head between the upper and lower flanges； If there is a high negative pressure inside the tank, the gauge must be installed below the lower flange; otherwise, it will cause significant errors in the instrument readings and may damage the differential pressure transmitter.
Generally, positive pressure is installed between flanges, while high negative pressure is usually installed below the lower flange.
The calculation results for the two positions are the same; EJA explicitly requires that it be below the high-pressure side, while Honeywell’s version allows it to be at a lower level in the middle – the main consideration is the direction of the force acting on the diaphragm box
I’m a new student; I want to learn some new things!
Say such things and first slap yourself twice – one slap shows a lack of manners, and the second slap is for not understanding something yet still blaming others. Do you think a double-flange level gauge is some kind of pressure transfer tube? How embarrassing