Bent Orifice Plates
Bent Orifice Plates
(OP)
Is there a correlation that can determine the error in an orifice plate reading after it has warped? For example, if I use an orifice plate to measure steam, then syrup (or heavy crude) and the viscosity of the syrup warps the plate, is there a method to determine that the flow rate is within some sort of window? (E.g. +/- 50%)
"If experience was always the only factor, how would we get to the moon?"
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RE: Bent Orifice Plates
RE: Bent Orifice Plates
Patricia Lougheed
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RE: Bent Orifice Plates
There are too many variables in a distorted plate (how bowed is it?, is the distortion symmetrical about both the vertical and horizontal axes?, did the event that damaged it also nick the leading edge?, etc.) that I've never seen an estimate of the amount of bias it creates.
If you need the bias to create an adjustment, then you need a point of reference. The reference point can be the sum of the upstream meters or the sum of the downstream meters, or a portable prover, or a strap on Ultrasonic.
David
RE: Bent Orifice Plates
The plate controls a steam flow control valve for injection. Despite having pressures where they need to be, the valve isn't opening enough to get the desired flow rate through. Either the valve isn't sized properly or the its not being controlled properly. After review, the valve is sized properly. Next step is to replace with a known good plate and try to replicate the problem.
"If experience was always the only factor, how would we get to the moon?"
http://www.piping-designer.com
RE: Bent Orifice Plates
It kind of sounds like you have a table in your algorithm that says for 15% open I will get "x" flow and for 40% open I will get "y" flow. If that is the case, then good luck. That is more reliance on the lineararity of a valve than I've ever been able to accept.
David
RE: Bent Orifice Plates
Guidelines For Measurement Errors Caused By Buckled Orifice Plates http:/
RE: Bent Orifice Plates
what dimensional atandard for the plates are you using, and what range of delta-P?
RE: Bent Orifice Plates
The end result isn't something to the accuracy of a University study or development of a set of equations but being able to go to the client and say (with reasonable certainty) "Yep, the problem's here; now here's how we're going to fix it" Thanks for the help
"If experience was always the only factor, how would we get to the moon?"
http://www.piping-designer.com
RE: Bent Orifice Plates
this is not a service for the traditional 1/8" plate
RE: Bent Orifice Plates