Electromagnetic flowmeter lining issues
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The medium under measurement is a solid-liquid two-phase mixture at normal temperature and pressure; considering that steam will be used to purge the pipes, we have employed a PFA lining. However, the PFA starts to bulge within less than a year. Teachers, do you have any good suggestions?:P
There are corrosive vapors; electromagnetic flowmeters made of PFA can handle up to 180 degrees. If money isn’t a concern, try using ceramic materials instead
Cologne has a PFA lining with an internally woven stainless steel mesh; it’s not expensive and might be more effective
Personally, I think it’s a problem with the lining. Due to frequent steam purging (likely used in production or filling lines for food, pharmaceuticals, biochemistry, dairy products, etc.), the lining is subjected to large temperature differences as the medium and steam pass through it alternately; as a result of thermal expansion and contraction, PFA separates from or even peels away from the inner wall of the measurement tube. The temperature resistance of PFA is not related to its thermal expansion and contraction when exposed to alternating hot and cold conditions, but rather to the process of stress accumulation and release resulting from such alternating temperatures in the lining material itself. It is recommended to use an electromagnetic flowmeter with a ceramic lining, or to switch to a Coriolis mass flowmeter that has no dead zones.