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Non intrusive flow meter 1

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engineeringguy

Mechanical
Apr 11, 2007
25
I have an application where my client is looking to meter his gross production in a heavy oil field (API 13). Initially, he started with a Vortex meter but the rubbers from the Sucker Rod Pumps are coming down the line and plugging it up. When its plugged, it caused the stuffing boxes upstream of the meter to leak badly. If this type of failure were to occur in the winter time, the lines would be plugged with cold oil and would require quite a bit of work to restore the wells.

Because these will be mounted remotely, it is desired to have as little or no maintenance as possible. (Pipe dream, I know). Aside from looking at a Liquid Ultrasonic or Cidra Sonartrac, what other options am I left with?





"If experience was always the only factor, how would we get to the moon?"

 
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There are several brands of the strap-on ultrasonics, but that is pretty much the waterfront for flow measurement from outside the pipe.

David
 
Fixed (not external clamp-on) ultrasonic are a good deal for this application too.
 
That was I was thinking and afraid of. My experience has been Daniel LUSM which is expensive & was a pain to start-up. Is there such a thing as a cheap, reliable LUSM?



"If experience was always the only factor, how would we get to the moon?"

 
Other vendors include GE Sensors (Panametrics) and Controlotron (some major owns them too, perhaps Siemens).
 
May be a silly question, why can't you use something like a Y strainer or some other knockout device before the vortex meter to catch all the bits and pieces?
Roy
 
That was my first question as well. There is a very high concentration of H2S in the crude so they want to limit exposure as often as possible. Its an established field so they don't want to spend a lot of money on additional infrastructure like vessels and other equipment that might IMPROVE the quality of their measurement. Gotta love client constraints. . .



"If experience was always the only factor, how would we get to the moon?"

 
What accuracy do they require? Generally I do not rely on UltraSonic meters for accuracy better than 5%. For clean fluid path try a mass flow meter. Danfoss did a single tube version, so the rubbers problem should be solved!

Mark Hutton


 
Well then why not a coreolis, one of the straight tube variety.
You don't give the line size. They are expensive but very accurate.
Roy
 
Coreolis meters are also a good selection where commercially practical. My preference is to limit their size at NPS 2 but have bought several at NPS 4. The smaller Coreilis meters are price competitive with the ultrasonic meters. Have the Coreolis meter manufacturer provide a calculation of the pressure drop for their proposed meters. Some meters with large flanges have smaller but multiple tubes. The pressure drop calculations help to level the playing field.

I would have fewer concerns regarding high density and especially viscosity with the Coreolis meter than ultrasonic.

One nice thing about the ultrasonic meters - you can pay field service to test an existing line with a clamp-on meter to verify that it functions in that fluid. Accuracy for the fixed ultrasonic may be better than two percent. Accuracy for the Coreolis meter should be far better than for the ultrasonic meters.
 
The best possible solution is a strap on sonrtrac flowmeter.It has been tested on heavy oil service (oilsands). It is easier to install and no shutdowns are required. The only catch is that fluid velocity has to be greater than 3 ft/sec. We've been using them on our site and they are virtually maintenance free. You can get more information at
 
**Update**

I was looking at Cidra Sonartrac and sent an inquiry to Rosemount. I have a quote for the Sonartrac and a Magmeter with some super diodes that supposedly get coated in an emulsion service. I'm not going to hold my breath but since both vendors are willing to give me a demo to try, I'll give them a test right next to eachother.

Thanks for the help all!



"If experience was always the only factor, how would we get to the moon?"

 
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