Dear All,
We are using Barton turbine flowmeters(Model:7304) for Water injection flow measurement in oil field. As per manufactures data this model has linear flow range between minimum 12Cum/Hr and maximum 284Cum/Hr only.
My question is

1)Is it possible to measure& get linear flow measurement in low flow (i.e)from 1 Cum/Hr to 10Cum/Hr by using this flow meter?

2)Or we go for some other flow meter for low flow range?

Expecting good suggestion and thanks in advance

 

It sounds to me that you are quoting the meters conventional performance i.e. the linear range as the range over which the meter factor is assumed to be a constant. This is a reflection of the early signal processing which usually relied on applying a single meter factor (pulses per unit volume). Hence, for a 1" meter, you might have a 10:1 linear range over which, with a constant meter factor, you would get 0.25% of reading or for a 20:1 range, 0.5% of reading.
The figures you quote are for a 4" meter? and if so, the range of 12 to 284 cmh is probably therefore the single meter factor range.
Modern signal processing allows the meter to be multi-point calibrated and for curve fitting to be used. That is, the meter is calibrated at a range of different flow rates and the meter factor varied with flow rate so the meter could be 0.25% accurate over a much wider range. The limiting factor is the minimum repeatable flow rate. You may find that Barton quote a minimum repeatable value for the meter and this may come close to the min flow you need.

If not you may find that installing a smaller second meter in a bypass is as cost effective as sourcing a meter that has a much wider linear flow rate range though mag meters, for example, can yield 1000:1 ranges and mass meters better than 100:1.

The first step is to ask Barton about a multi-point calibration or simply about the minimum repeatable flow (you might find this on the meter data sheet or you should have a calibration certificate somewhere that may tell you more).

 

I see ACCELABAR from Veris, Inc. USA as a good choice for water injection flow metering. The advantage is that it is a DP Flow Technology, doesn't require straight lenght to produce an accuracy of +/-0.75% of reading, the turn down is 65:1.

-Rohit Chandak

 

If you want a mostly maintenance free meter for this application, and the water has a minimum conductivity of 5 uS, a magnetic flowmeter will give you better accuracy, better turndown, and essentially better maintenance free operation than any Differential Pressure flow meter. And I'd like to see just once a multiport pitot tube meter with an honest 65:1 turndown. Never happen. See the _Consumer Guide to Differential Pressure Flow Transmitters_ by Spitzer and Boyes for honest comparisons...

Walt Boyes
Editor in Chief
Control magazine
www.controlglobal.com
blog:Sound OFF!! http://www.controlglobal.com/soundoff
_________________

Putman Media Inc.
555 W. Pierce Rd. Suite 301
Itasca, IL 60143
630-467-1301 x368
[email protected]

 

ACCELABAR is a combination of two DP technologies, Venturi & Averaging Pitot Tube, wherein Venturi is being used as a flow conditioning device & not as a measuring device. Nozzle accelerates, linearizes & stabilizes the velocity profile. VERABAR located in the nozzle accurately measures & significantly increases the DP output. The data from testing confirms the turndown of 65:1.

It would be my pleasure to send you testing data which will confirm the turn down as well as accuracy without the need of long straight length.

You can also visit http://www.veris-inc.com to have more information.

-Rohit Chandak

 

Please do. I'd be very happy to see it. Did you send it to us when we solicited it for the book? No.

Walt Boyes
Editor in Chief
Control magazine
www.controlglobal.com
blog:Sound OFF!! http://www.controlglobal.com/soundoff
_________________

Putman Media Inc.
555 W. Pierce Rd. Suite 301
Itasca, IL 60143
630-467-1301 x368
[email protected]

 

Please send it to me too, [email protected]

dennis

 

And to me as well.

Tomnelson @ racinefed. com

 

Dear Mr. JMW,

Your information is very useful to us, and this may help to improve existing system. Meanwhile we are trying to contact Barton peoples. Thanks for your suggestion.