Installation issues with clamp-type electromagnetic flowmeters
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Hello everyone, I have a question. When installing a clamp-on electromagnetic flowmeter, the flanges at both ends are welded together; due to differences in the wall thickness of the flange areas compared to that of the pipeline itself, steps are formed inside, and these steps are located quite close to the flowmeter. Will this have a significant impact on the accuracy of the flowmeter? Moreover, the upstream and downstream pipes are not at the same level when no flow meter is installed; there is a difference of about 2 cm between their axes. Will this cause damage to the flow meter after it is installed? E+H’s H300 series flowmeter, with a DN50 specification. Thank you first!
My understanding is that as long as the pipeline has a slope, it doesn’t cause any problem.
Uh, yes. The installation itself has a slope; as long as the inlet of the instrument is lower than the outlet, the usage conditions are met. I mainly want to ask if the internal wall steps will affect precision ； And whether the pipes before and after installation being at different levels could cause damage to the instruments or to the pipes themselves. Thank you as well for your reply.
A difference in diameter between the pipeline and the flow meter is a common issue, usually caused by incomplete information regarding flange standards and pipeline parameters at the time of ordering. I have seen metering systems for coal slurry flow; to protect the lining, a protective ring with a diameter smaller than that of the pipe is installed at the inlet of the flow meter, and no significant inaccuracies were observed during use. In addition, it’s better to ask E+H about this situation, as they are responsible for the measurement results. As for the height difference between the front and rear pipes, it is sufficient to add a support on each side of the process pipe.
Well, I asked the engineers at E+H, and they said that the issue with the steps would have an impact, but it wouldn’t be very significant. I just think it’s a shame that such precise instruments have pipes made in this way. . . Thank you for your answer! I’ve learned something!