In one of our projects we are using Electromagnetic (EM) flowmeters in high pressure subsea water injection lines. The pressure in the line is very high, API 10000 ( i.e. approx. 500 bar). Line size is 12". We are feeling little bit uneasy about the application since EM flowmeters are not normally used for such high pressure applications. For vendors this is normally not in their regular product line and will be customised for us.
I will be glad to know if any of our friends in this forum have any experience of using EM flowmeters in high pressure applications. Any insight gained through real life experience on this matter will be extremely beneficial for us.
I have never used anything close to that. The highest our usual suspect list is 2500#. Is it balanced by being submersed i.e. pressure on the outside close to what's on the inside?
Otherwise could you measure the flow before the pump?
12" at 500 bar? Not your stock magmeter.
This sounds like an application for a clamp-on flowmeter (that doesn't care about the pressure because it doesn't 'see' the pipe pressure), but I have no idea whether GE/Siemens/Flexim models are suitable for subsea service.
I am giving some more information about this application. There are 2x100% water injection pumps. Pump discharge goes to a common header and from the header 3 pipelines goes to the oil wells under the sea. Pumps and flowmeters are above the sea on the topside module. Yes this is a special application. Most of the regular vendors have denied such a product. One well known vendor has confirmed to make such a flowmeter. However, this is not in their regular product range as well.
We are looking for alternative flowmeters also. Clamp-on, Orifice and Venturi are also alternative choices. I know at least in one project (Tullow offshore) Emerson has used Venturi in 500 bar gas injection pipeline successfully. To make our life measurable Process has defined another two criteria - rangeability 16:1 and accuracy +/- 3%. Clamp on may be a viable alternative, but careful consideration is required to achieve such accuracy. We are still exploring!
We have used McCrometer V-Cone differential head flowmeters in our oil field. Because of the design the upstream requirement 0-3 diameters and 0-1 downstream, accuracy is +/- 0.5% of rate, repeatability +/- 0.1% , Pressure range 20,000 PSI (1380 bar), line sizes 0.5" - 120", End connections can be custom our meters were API 5K. Materials are custom. Our pipeline was API 5L Grade X65 which was expensive. We actually sent the manufacture a section of our pipe and flanges from our stores to fabricate the meter. This saved a large amount of money because McCrometer would have had to pay a premium for this material.
See this website location https://www.mccrometer.com/v-cone-flow-meter/product-details?id=52003823651
Thanks for sharing your experience. Yes, we have also contacted McCrometer and they have confirmed such applications. Only problem we see here is the rangeability. 10:1 is easily possible by V-cone, but for 1 tag process is asking for 24:1 rangeability. Anyway, definitely this is a viable option.
Thanks for your note on pipeline material and supply to McCrometer a section of the pipe to reduce cost.
Just one question, how did you make sure of 0.5% accuracy? A wet calibration was done?