Orifice meter - wrong installation
Orifice meter - wrong installation
(OP)
We have an gas orifice meter that was wrongly installed, with the conical opening facing the wrong way. Unfortunately there are was external indication of flow direction, and assurances had been given that it was correctly installed - something that could probably justify a separate thread on QA, but I'll pass on that subject for now. 
Anyway, when the orifice plate was repositioned, measured flowrates increased by about 10-15 percent (flow is unfortunately not constant, so a direct comparison is not possible), and I was wondering if there is any way to recalculate the old (erroneous) readings that we have?
Anyway, when the orifice plate was repositioned, measured flowrates increased by about 10-15 percent (flow is unfortunately not constant, so a direct comparison is not possible), and I was wondering if there is any way to recalculate the old (erroneous) readings that we have?





RE: Orifice meter - wrong installation
http://www.eng-tips.com/viewthread.cfm?qid=250966
RE: Orifice meter - wrong installation
RE: Orifice meter - wrong installation
RE: Orifice meter - wrong installation
When I was operating a gathering system we had a couple of big wells get backwards plates. I applied a 26% factor to the data and my system material balance went from +5% to +2% (there were other problems in the system at that time as well). The problem with that technique is that it is rare to have the ability to do a material balance because someone else usually operates the aggregation meter.
David
RE: Orifice meter - wrong installation
It is (unfortunately) a fiscal meter, although the measurement is only for injection gas, for which the company is obliged (and previously seemed to fail) to provide a minimum amount of throughput per day.
Indications are that measurement has been off by about 15-20%, but it appears that making an accurate calcualtion of what amount has been underreported is rather difficult.
Appreciate the leads given above, though - at least it gives me something to work with.