Coriolis Mass Flow Meter Working Principle




The operation of a Coriolis flow meter is based on the mechanics of motion. The Coriolis force happens when a mass moves in a rotating inertial frame. The rotation is created by vibrating two opposing tubes on the flow meter. When a fluid flows through the opposed vibrating tubes, the tubes twist due to the Coriolis force. The twisting alternates with the vibration and creates two phase-shifted sinusoidal wave forms on coils mounted to the tubes. The amount of shift is proportional to the mass flow rate. In addition, the frequency of vibration is proportional to the fluid density. The signal shift and the frequency of vibration can be precisely measured, which makes the Coriolis meter one of the most accurate types of flow meters.

As this principle measures mass flow independent of what is within the tube, it can be directly applied to any fluid flowing through it – LIQUID or GAS – whereas thermal mass flow meters are dependent of the physical properties of the fluid.  Furthermore, in parallel with the phase shift in frequency between inlet and outlet, it is also possible to measure the actual change in natural frequency. This change in frequency is in direct proportion to the density of the fluid – and a further signal output can be derived. Having measured both the mass flow rate and the density it is possible to derive the volume flow rate.




Coriolis meter main Features

  • A Coriolis meter can be applied for variety of applications ranging from adhesives and coatings to liquid nitrogen.
  • Typical rangeability of curved tube designed Coriolis meters vary from 100:1 to 200:1 whereas for straight-tube meters its rangeability is limited i.e. about 30:1 to 50:1. Besides, accuracy of straight tube meters is low.
  • In case of Coriolis meters, no compensation is needed for temperature and pressure variations. Also mass measurement is insensitive to changes in viscosity and density.
  • They are particularly helpful for handling liquids whose viscosity changes according to velocity while temperature and pressure remains constant.
  • These are called universal meters, since they are capable enough to measure nearly all liquids, slurries and gases. They can measure all liquid flows such as Newtonian, non-Newtonian and moderately dense gases as well.
  • They can be employed to measure liquid density also.
  • No Reynolds number restrictions are allied with Coriolis flow meters.
  • They are also not affected by deformations in velocity profile







Coriolis meter Technical specification

Sizes :-

1 / 25 to 10 in. (1 to 250 mm)

Fluids Liquids:-

slurries, gases (compressed, low-pressure, etc.), liquefied gases; not gas-liquid mixtures

Flow Range  :-

0 to 63,000 lb /min (0 to 28,300 kg/min)

Operating  Pressure :-

Depends on tube size and flange rating: 1400 PSIG (100 bar) typical standard rating;5000 PSIG (345 bars) typical high-pressure rating.

Operating  Temperature: –

 Depends on design:  − 60 to 400 ° F ( − 50 to 200 ° C) typical standard; 32 to 800 ° F(0 to 426 ° C) high-temperature, special versions also used for cryogenic applications.

Measured Variables :

Mass flow, volume flow, density and temperature

Pressure Drop :-

Function of flow, viscosity, and design, varying from very low (<0.1 PSIG, 10 mbar) to moderately high (22 PSIG approximately 1.5 bar) 

Price :- 

Depends on size and design: 1 / 25 in. (1 mm), $5000; typical 1-in. (25-mm) meter, $7000; 6-in. (150-mm), $27,500.

Coriolis flow meter advantages and disadvantages




Advantage of Coriolis flow meter :-

  • Coriolis flow meter is capable of measuring a wide range of fluids that are often incompatible with other flow measurement devices. The operation of the flow meter is independent of Reynolds number; therefore, extremely vicious fluids can also be measured. A Coriolis flow meter can measure the flow rate of Newtonian fluids, all types’ non-Newtonian fluids, and slurries. Compressed gases and cryogenic liquids can also be measured by some designs.
  • Coriolis flow meters provide a direct mass flow measurement without the addition of external measurement instruments. While the volumetric flow rate of the fluid will vary with changes in density, the mass flow rate of fluid is independent of density changes.
  • Coriolis flow meters have outstanding accuracy. The base accuracy is commonly on the order of 0.2%. In addition, the flow meters are linear over their entire flow range.
  • The rangeability of flow meters is usually on the order of 20:1 or greater. Coriolis flow meters have been successfully applied at flow rates 100 times lower than their full scale flow rate.
  • A Coriolis flow meter is capable of measuring mass flow rate, volumetric flow rate, fluid density and temperature — all from one instrument.
  • The operation of the flow meter is independent flow characteristics such as turbulence and profile. Therefore, upstream and downstream straight run requirement and flow conditioning are not necessary. They can also be used in installations that have pulsating flow.
  • Coriolis flow meters do not have internal obstructions witch can be damaged or plugged by slurries or other types of particulate matter in the flow stream. Entrained gas or slugs of gas in the liquid will not damage the flow meter. There are no moving parts witch will wear out require replacement. These design features reduces the need for routine maintenance.
  • The flow meter can be configured to measure flow in either the forward or the reverse direction. In revere flow there will still be a time or phase difference between the flow detector, but the relative difference between the two detector signals will be reversed.
  • Coriolis flow meter designs are available witch allow for use in sanitary applications, and for the measurement of shear sensitive fluids. Materials are available to permit the measurement of corrosive fluids.






Disadvantage of Coriolis flow meter  :-

  • Coriolis flow meters are not available for large pipelines. The largest Coriolis flow meter that is currently available has a maximum flow rating of 25,000 lb/min (11,340 kg/min), and is equipped with 6 in. (15 cm) flanges. When larger flow rates must be measured, two or more flow meters mounted in parallel are required.
  • Some flow meter designs require extremely high fluid velocities in order to achieve a significant amount of time or phase difference between the flow detector signals. This can result in extremely high pressure drops across the flow meter.
  • Coriolis flow meters are expensive. However, the cost of a Coriolis meter is often comparable to (or below) the cost of a volumetric meter plus densitometer used together to determine the mass flow rate.
  • Coriolis flow meters have difficulty measuring the flow rate of low- pressure gas. Application with pressure less than 150 psig are marginal with the flow meter designs that are currently available. Low-pressure gases have low density, and their mass flow rate is usually very low. In order to generate enough mass flow rates to provide sufficient Coriolis force to be measured, the gas velocity must be extremely high. This in turn may lead to prohibitively high pressure drops across the meter.




Technical Specification of  Coriolis flow meter

Sl. No.ParameterMinimum Requirements
1Line size1.5”/ 2”/3”/4” NB
2Service

MS/SKO/HSD/ATF/ETHANOL/BIO                  DIESEL

(Volumetric Flow)

3Flow Min/ Operating/MaxFor 2”/1.5” line : 30/300/ 500 LPM
For 3” Line    : 200/1200/ 1500 LPM
For 4” Line    : 200/2000/2400 LPM
4Operating Pressure1 to 8 Kg/cm2
5Operating tempRefer Site Data
6Operating density

MS   :  0.70-0.75 gm/cc

SKO : 0.75-0.80 gm/cc HSD :  0.80-0.90 gm/cc

7Viscosity @ 38 deg C

MS   :  1.1 CST

SKO :  1.2 CST

HSD : 2.54 – 4.0 CST

8

Allowable Pressure Drop across

MFM

Maximum 0.5 Kg/cm2 @ Maximum flow rate
9Relative humidity limit95% non-condensing
10TypeMicroprocessor based Coriolis mass flow meter
11Transmitter typeRemote / Integral
12Sensor TubeSS 316 / SS 904L or better
13Wetted partsSS 316 /SS 904L or better
14Flow directionBi directional flow
15Tube size (sensor)To be sized by vendor




16Transmitter Body MaterialSS 304 / Die cast aluminum
17Process connection

1.5”/2”/3” / 4”RF, ANSI # 150 B16.5 (As per line

size)

18End connection MaterialSS 316/ SS 316L
19Mounting accessoriesRequired (As Applicable)
20Accuracy(For flow range 10%-100% of Maximum Flow rate)
iMass+/- 0.05%
iiVolume+/- 0.05%
iiiDensity+/- 0.0002 gm/cc
21Repeatability

Mass/ Volume : +/- 0.025%

Density : +/- 0.0001 gm/cc

22Batch Accuracy± 0.05% over full range
23

Minimum Data to be displayed

on Local Display

·   Mass/Volume flow rate (Selectable)

·   Mass/Volume totaliser (Selectable)

·   Online Temperature

·   Online Density

  • Totaliser Mass/Vol.(Selectable)

Other parameters at MFM/ Flow computer

  • Corrected Volume @ 15oC/29.5oC (Selectable)
  • Density@ 15oC/29.5oC (Selectable).
    • Volume and Density conversion at 15oC/29.5oC are to be done using inbuilt ASTM table loaded in MFM/ Flow
    • Conversion using mathematical formula shall not be
    • At one of the above mentioned parameters shall be displayed at a time with a provision of Auto Scrolling (configurable)for viewing

other parameters




24Electrical Connection

Suitable Cable entries with FLP double compression

(Ni-Plated) Cable Gland to be provided as per design Engineering.

 

Cable entry size shall be suitable for following cable type

a.    Power cable : 3Cx2.5 sq.mm Armoured Cu FRLS

b.    Signal cable : 2 pair x 1.5 sq.mm Armoured Cu FRLS (as applicable)

c.    Cat 6 cable

25Power supply230 VAC, 50 Hz +/- 5%
26Power consumptionVendor to specify
27Signal Input /Output

Ø  Frequency

Ø  4-20 mA / HART

Ø  Modbus TCP IP

Following parameters shall be available as minimum over Modbus TCP/IP to TAS:

·   Mass and Volume flow rate

·   Mass and Volume totalizer

·   Online Temperature

·   Online Density

·   Meter-factor

·   Corrected Volume @ 15oC/29.5oC (Selectable)

·   Density@ 15oC/29.5oC (Selectable)

·   Critical Diagnostic data of MFM

Ø  Volume and Density conversion at 15oC/29.5oC are to be done using inbuilt ASTM table loaded in MFM/ Flow Computer.

Ø  Conversion using mathematical formula or ASTM table loaded in TAS shall not be accepted.

28

Reset counter and cumulative

totalizer

The    Flow    Transmitter/Display    Unit    shall    be

equipped   with   minimum   8   Digits   Cumulative

Totalizer    &    5     Digit    Reset    Counter     with

programmable decimal.




29Surge Protection

The   MFM   shall   be   protected   against  surges,

transients induced either by switching of heavy electrical loads or lightning. Compatible surge protectors recommended by OEM for signal and power supply, with necessary mounting accessories shall be included in the offer. The surge protector shall be designed and tested as per the requirements  of  BS  EN  62305  /IEEEC62.41  /IEC

61643-21

30W&M Lock

Yes, Software and Hardware lock for sealing to be

provided

31Connectivity

Ø The frequency/ pulse output of the MFM to be connected to BCU for Mass/ Volume flow

rate.The signal shall be linearly proportional to the volume / Mass flow rate which shall be read by the batch controller. Number of pulses generated for a unit Volume/Mass transferred, shall be user configurable.

Ø Temperature Transmitter output to be connected to MFM/ Flow Computer for Temperature reading and compensation.

Ø TCP IP output to be connected to TAS from MFM for remote display of all the above mentioned parameters in TAS including compensated Volume and Density at 15 Deg/ 29.5 Deg C.

32Area classificationZone 1, Group II A& B T3
33Housing ProtectionWeather proof to IP65 or better & Explosion proof
34Approval

·         CCOE / PESO

·         CMRI/ ATEX

·         Type / Model approval from Indian Legal Metrology.

·         PTB/NMI – OIML R117 for Custody transfer

35Calibration

Master MFMs shall be calibrated at FCRI Palakkad before dispatch.

All other MFMs needs to be calibrated at respective OEM’s laboratory or at any NABL accredited Laboratory or at FCRI Palakkad before despatch in addition to proving and W&M stamping at site.




Mass Flow Meter Inspection and Test Plan 

This content provides you a sample mass flow meter inspection and test plan. This is a draft mass flow meter ITP and you need to modify it to meet your specifications.

Mass Flow Meter Inspection and Test Plan TaskVendorTPI InspectionClient
Mass Flow Meter Mill test reportsHRR
Mass Flow Meter Pressure testHWR
Mass Flow Meter Performance test including calibration and hysteresis testsHWR
Mass Flow Meter Insulation resistance testHWR
Mass Flow Meter Final visual / Dimension InspectionHHR
Mass Flow Meter Documentation review prior to release(Final activity of Technical Inspection)HHR
Mass Flow Meter Pre-shipment InspectionHHR





H: Hold Point implies that relevant production activities shall not proceed until the continuation of work is permitted by Purchaser. (Notification req’d)

W: Witness point implies that Purchaser intends to witness the designated inspection feature. If Purchaser decides not to witness the relevant feature, production can proceed without permission of Purchaser. (Notification req’d)

S: Witness, but spot check basis. Initial operation will be witness point and subsequent operation will be witnessed at discretion of Purchaser considering the results of previous inspection. (Notification not req’d : Randam Inspection)

R: Review inspection & test records (Notification not req’d)

 

General Note :

1) Mass Flow Meter Witness/hold point by Code Inspector, when applied by Code /Local Regulation, is to comply with its requirements and to specify in Vendor’s ITP.

2) Type of Inspection by Mass Flow Meter Purchaser may be changed according to equipment criticality and vendor QC evaluation at job stage.

3) When requested in the requisition, detailed Mass Flow Meter ITP shall be submitted by Vendor.

4) Monitoring/Observation of Mass Flow Meter Vendor shop daily routine works (i.e.Storage of materials, Adherence to approved procedures, Testing tool calibration check, workmanship,cleanliness and etc.) shall be done by Purchaser during inspection visit.

5) 100%  Mass Flow Meter inspection which is covered by the combination of witness / spot check / record review inspection & tests listed above and vendor’s original QC activity shall be confirmed by Purchaser’s inspector prior to shipment.

6) Unless otherwise specified in REQ., the Mass Flow Meter sampling Q’ty of ” S (Spot Witness Check) ” shall be as follows:

3 to 20→3Pcs(all if total 2 and less) , 21 to 50→5Pcs, 51 to 100→10Pcs,101 to 200→20Pcs, 201 to 300→30Pcs, 301 to 500→50Pcs

Minimum 25 pcs or more of the commodity shall be arranged for H/W/S inspection and test at one time inspector’s visit as much as practical.

7) Final Mass Flow Meter Visual Inspection/Documentation Review/Pre-Shipment Inspection may Pre be combined within one time visit.



Coriolis flow meter connections 




Coriolis Flow Meter Calibration Procedure :

Coriolis Flow Meter Calibration Procedure | Helloinstru




Top five Coriolis flowmeter Manufacturer




Coriolis Mass Flow meter Manufacturers / VendorsCountryWebsitePhone No.
ABB AGGERMANYwww.abb.de+49 62143810
ABB LIMITEDUKwww.abb.com+44 1925741111
BOPP & REUTHER MESSTECHNIK GMBHGERMANYwww.burmt.de+49 6232657508
DANIELUKwww.daniel.com+44 1786433400
EMERSONUKwww.frco.com+44 1162822822
ENDRESS & HAUSERGERMANYwww.endress.com+49 71562090
HONEYWELLBELGIUMwww.honeywell.be+32 27282386
JORDAN KENT(ALDERLEY)UK +44 1454294556
KOBOLD MESSRING GMBHGERMANYwww.kobold.com+49 61922990
KROHNE MESSTECHNIK GMBH & Co. KGGERMANYwww.krohne.de+49 2033010
MECI S.A.SFRANCEwww.meci.fr+33 254039949
OVAL CORPORATIONJAPANwww.oval.co.jp+81 333605121
SIEMENSGERMANYwww.powergeneration.siemens.com+49 9131180
SMITH METER (FMC)GERMANYwww.fmcmeasurementsolutions.com+49 41013040
YOKOGAWA ELECTRIC CORPU.A.E +973 17358100

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