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Coriolis ELITE - Parameter check for any deposit on tube

Dear Coriolis Expert,

What parameter on coriolis (to be precise on 5700 transmitter) which indicate that there is deposit or plugging on tube?, are SMV and Zero Verification enough?,

need help with detail technical explanation on this.

Thank you in advance,

Faiz

3 Replies

  • Hi again Faiz - you are definitely on the right track.  The detection of coating or scale buildup inside a Coriolis sensor can be a challenge depending on how much buildup is actually present, how it's distributed, and how closely its density matches the surrounding fluid.  Detecting it under flowing conditions is the most challenging scenario. 

    Micro Motion's Smart Meter Verification (SMV) Basic, which is now included with most sensors at no charge, is designed to look for changes in the stiffness of the tubes caused by mechanical transformation (such as erosion or corrosion).  Unfortunately, many coating deposits, like paraffin wax, do not affect the overall tube stiffness and may go unnoticed by our basic SMV tests. 

    On the other hand, the optional SMV Professional package includes a "non-uniform" coating diagnostic.  It works by looking for a trending separation between the two pickoff signals due to repeatable tube imbalances – a plugged tube would be easy to detect this way.  The hard part is guessing whether your coating will be uniform.  Some coatings will build from one-side-in and be detectable almost immediately, whereas others will build slowly and steadily until the process is impacted before an alarm is raised.  Other variables to look at:

    • Zero – changing or drifting readings at no flow can be a sign of coating, especially if SMV passes.
    • Density – if the density of the coating is significantly higher or lower than the rest of the process fluid, a trend toward the density of the coating should indicate that more of it is present.
    • Air or Water Tube Frequency – the calibration coefficients on the meter tag indicate what the tube frequency should be when full or air (1/K1*1,000,000) or water (1/K2*1,000,000) at ambient conditions. If you blow the meter down with air, and the frequency is too low, or you fill it with clean water and the frequency does not match the cal sheet, you may have a coating issue.
    • Drive Gain – this is a measure of how much energy is required to drive the tube oscillations. More energy is required to drive a meter that is out-of-balance due to coating.  Under similar conditions, if the drive gain trends higher over time, you may have coating in the tubes.

    I hope this helps.  Feel free to reach out to Flow.Support@Emerson.com to receive a more specific diagnosis if you have process data you’d like to share.

  • In reply to Jared Drennen:

    Hi Jared,
    Thank you for the great explanation.

    So during flow condition, options that we have for deposit checking on tubes are: (cmiiw)
    1. SMV basic + monitor drive gain reading.
    Next step (during no flow) : zero verification and perform checking for air and water tube freq

    Or

    2. SMV Professional

    Another questions are:
    1. Can we look at also at left and right pickoff voltage value to indicate for any tube unbalance?
    2. We did the installation with vertical orientation, would it be reduced the possibility for any deposits on tube
    3. SMV Pro means the licensed on 5700, it's not the Prolink version . Is it right?
    4. If we have just SMV Basic. In order to be the professional version, would it be done by purchasing the license and upgrade 5700 firmware?

    Thank you in advance,
    Faiz

  • In reply to Faiz Faiz:

    Hi Faiz - one minor correction - SMV Basic does not detect coating.  To identify coating during flow, you can try to use density, drive gain, pickoff voltages, and possibly flow rate (if the tubes are actually being restricted).  During non-flow, check zero, density, and tube frequency under known fluid conditions.  As to your other questions:

    1. Yes, you can monitor the pickoff voltages yourself (map them to an external Modbus host for example), but since these values are automatically included in the built-in historian data, you could also review them after a known buildup or blockage to see how they responded leading up to the event.  
    2. Vertical flowing up is recommended for all liquid flow regimes - to ensure the tubes stay full, and prevent any bubbles or solids from collecting in the tubes.
    3. Yes, SMV Pro needs to be licensed in the transmitter in order to activate the coating detection monitoring and associated alarms.  However, Prolink is required to generate the associated reports (since the transmitter has no way of printing or creating a PDF).  It is recommended to run SMV Pro no less than once per week when coating is suspected (possibly more depending on deposition time).  It can be set to run automatically on a schedule, ideally when conditions will be calm (flow is okay, but too many bubbles or process noise may cause it to abort).
    4. Lastly, yes - the upgrade from SMV Basic to Pro is a simple license upgrade that can be done through the LOI or a connected USB laptop with Prolink.

    One thing I forgot to mention that is specific to paraffin detection is Temperature monitoring.  You can set an alarm to alert you if the temperature drops below a certain setpoint.  This is highly useful for detecting failed heaters or jacketing systems.