Can Flow be measured accurately by Pressure Transmitter
Can Flow be measured accurately by Pressure Transmitter
(OP)
Helow
Please advise, if a discharge Pressure transmitter (not differential) downstream a Centrifugal pump can be used to measure an accurate corresponding flow? Is this normally acceptable in Industry?
Thanks, Niss
Please advise, if a discharge Pressure transmitter (not differential) downstream a Centrifugal pump can be used to measure an accurate corresponding flow? Is this normally acceptable in Industry?
Thanks, Niss





RE: Can Flow be measured accurately by Pressure Transmitter
It is by no means an accurate measure of the flow.
RE: Can Flow be measured accurately by Pressure Transmitter
RE: Can Flow be measured accurately by Pressure Transmitter
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Can Flow be measured accurately by Pressure Transmitter
RE: Can Flow be measured accurately by Pressure Transmitter
Is it acceptable? As with anything, it depends on how you are using the information. Differential pressure along with motor amps can get you a pretty good idea, again for a new pump with a steep curve.
RE: Can Flow be measured accurately by Pressure Transmitter
Flow is on the X axis. Head and horsepower are on they Y. If you mark the head (based on measured differential pressure) and the horsepower (based on measured motor amps) and draw vertical lines, they should be very close to each other and you can determine an approximate flow.
Let's assume the pump is a little less efficient than when it was new. This means your power is higher, and your pressure is lower, for a given flowrate. All that does is put the two lines farther apart, but the actual flow is still somewhere in between.
RE: Can Flow be measured accurately by Pressure Transmitter
RE: Can Flow be measured accurately by Pressure Transmitter
ITT Goulds does offer a VFD (PumpSmart) that will achieve flow control to a claimed accuracy of +/- 5% using the measured power. Obviously this would require neither a pressure sensor or a flowmeter. The main drawback is that it won't work in applications that handle different densities of fluid.
The link for it is below
https://www.ittproservices.com/ittgp/medialibrary/ITTPROServices/website/Literature/Brochures/PRO%20Services/PSmartbulletin.pdf?ext=.pdf
RE: Can Flow be measured accurately by Pressure Transmitter
Thank you for feed back.
Best Regards
Niss