densitometer non-radioactive nrd op & maint toc

31
Non Radioactive Densitometer NRD Operators & Maintenance Manual Table of Contents Revision AB 1 Schlumberger Dowell SECTION SUBJECT PAGE 1.0 PRINCIPLE ................................ ................................ ................................ ....................... 3 1.1 NRD Density Measurement Principle ................................ ................................ ................ 4 1.2 NRD Flow Rate Measurement Principle ................................ ................................ ............ 5 2.0 PERFORMANCES ................................ ................................ ................................ ............ 7 2.1 Performance Specification ................................ ................................ ................................ 7 2.2 Accuracy ................................ ................................ ................................ ........................... 7 3.0 MOUNTING AND MECHANICAL CONNECTIONS ................................ ......................... 9 3.1 Mounting ................................ ................................ ................................ ........................... 9 3.2 Mechanical Connections ................................ ................................ ................................ ... 9 3.3 Orientation ................................ ................................ ................................ ....................... 10 3.4 NRD For Acidizing Mounting ................................ ................................ ........................... 10 4.0 ELECTRICAL CONNECTIONS ................................ ................................ ...................... 15 4.1 Sensor To The RFT 9712 ................................ ................................ ................................ 15 4.2 Electronic RFT 9712 to the J-BOX (PACR) ................................ ................................ .... 17 4.3 RFT 9712 To The ECM Of The VIP Mixer™ ................................ ................................ ... 17 5.0 START UP ................................ ................................ ................................ ....................... 19 5.1 Power On ................................ ................................ ................................ ......................... 19 5.2 Meter Zero ................................ ................................ ................................ ....................... 19 5.3 Flow Totalizer ................................ ................................ ................................ .................. 21 5.4 PACR And PPR Configurations ................................ ................................ ...................... 21 5.5 Valves Configuration During Density Build Up and Pumping ................................ .......... 23 6.0 CALIBRATION ................................ ................................ ................................ ................ 25 6.1 Density Calibration Factor Determination ................................ ................................ ........ 25 6.2 Flow Calibration Factor Determination ................................ ................................ ............ 28 7.0 TROUBLE SHOOTING ................................ ................................ ................................ ... 31 7.1 LED Fault Indications ................................ ................................ ................................ ...... 31 7.2 Failure Symptoms and Trouble Shooting Procedure ................................ ...................... 32 7.2.1 Power Failure: ................................ ................................ ................................ .......... 32 7.2.2 Density Offset: ................................ ................................ ................................ .......... 32 7.2.3 Major Failure: ................................ ................................ ................................ ........... 34 8.0 USING THE SMART COMMUNICATION INTERFACE MODEL 268 ............................ 41 8.1 268 Connections ................................ ................................ ................................ .............. 41 8.2 Operation Diagram ................................ ................................ ................................ .......... 41 8.3 PC Based Programmer ................................ ................................ ................................ ... 43 9.0 SPARE PARTS LIST ................................ ................................ ................................ ....... 45

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  • Non Radioactive Densitometer NRDOperators & Maintenance Manual Table of Contents

    Revision AB 1Schlumberger

    Dowell

    SECTION SUBJECT PAGE

    1.0 PRINCIPLE ................................ ................................ ................................ ....................... 31.1 NRD Density Measurement Principle ................................ ................................ ................ 41.2 NRD Flow Rate Measurement Principle ................................ ................................ ............ 5

    2.0 PERFORMANCES ................................ ................................ ................................ ............ 72.1 Performance Specification ................................ ................................ ................................ 72.2 Accuracy ................................ ................................ ................................ ........................... 7

    3.0 MOUNTING AND MECHANICAL CONNECTIONS ................................ ......................... 93.1 Mounting ................................ ................................ ................................ ........................... 93.2 Mechanical Connections ................................ ................................ ................................ ... 93.3 Orientation ................................ ................................ ................................ ....................... 103.4 NRD For Acidizing Mounting ................................ ................................ ........................... 10

    4.0 ELECTRICAL CONNECTIONS ................................ ................................ ...................... 154.1 Sensor To The RFT 9712 ................................ ................................ ................................ 154.2 Electronic RFT 9712 to the J-BOX (PACR) ................................ ................................ .... 174.3 RFT 9712 To The ECM Of The VIP Mixer ................................ ................................ ... 17

    5.0 START UP ................................ ................................ ................................ ....................... 195.1 Power On................................ ................................ ................................ ......................... 195.2 Meter Zero ................................ ................................ ................................ ....................... 195.3 Flow Totalizer ................................ ................................ ................................ .................. 215.4 PACR And PPR Configurations ................................ ................................ ...................... 215.5 Valves Configuration During Density Build Up and Pumping ................................ .......... 23

    6.0 CALIBRATION ................................ ................................ ................................ ................ 256.1 Density Calibration Factor Determination ................................ ................................ ........ 256.2 Flow Calibration Factor Determination ................................ ................................ ............ 28

    7.0 TROUBLE SHOOTING ................................ ................................ ................................ ... 317.1 LED Fault Indications ................................ ................................ ................................ ...... 317.2 Failure Symptoms and Trouble Shooting Procedure ................................ ...................... 32

    7.2.1 Power Failure: ................................ ................................ ................................ .......... 327.2.2 Density Offset: ................................ ................................ ................................ .......... 327.2.3 Major Failure: ................................ ................................ ................................ ........... 34

    8.0 USING THE SMART COMMUNICATION INTERFACE MODEL 268 ............................ 418.1 268 Connections ................................ ................................ ................................ .............. 418.2 Operation Diagram ................................ ................................ ................................ .......... 418.3 PC Based Programmer ................................ ................................ ................................ ... 43

    9.0 SPARE PARTS LIST ................................ ................................ ................................ ....... 45

  • Non Radioactive Densitometer NRDTable of Contents Operators & Maintenance Manual

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    Appendix 1: Exploded Drawing Of The RFT 9712 ................................ ............................... 47Appendix 2: Temperature and Density of Water ................................ ................................ .. 49Appendix 3: 268 Interface Operation Diagram ................................ ................................ ..... 51Appendix 4: RFT 9712 Configuration Record ................................ ................................ ...... 53Appendix 5: NRD Failure Report ................................ ................................ .......................... 55Appendix 6: RFT 9712 to Sensor Cable Preparation Instruction ................................ ......... 57Appendix 7: DS300S Dimensions ................................ ................................ ........................ 61Appendix 8: Equipment Selection Form ................................ ................................ ............... 63

  • SchlumbergerDowell

    NON RADIOACTIVE DENSITOMETERNRD

    OPERATORS & MAINTENANCEMANUAL

    PN 962095000 AB

  • Non Radioactive Densitometer NRD Section OneOperators & Maintenance Manual Principle

    Revision AB 3Schlumberger

    Dowell

    1.0 PRINCIPLE

    The Micro-Motion Mass Flowmeter DS300S with its electronic RFT 9712 has beenqualified as the Non Radioactive Densitometer NRD for Dowell SCHLUMBERGERcementing applications (cement slurries, oil/water based muds).

    It is a 3 inch double tube upstream densitometer and flowmeter with a maximummass flow rate of 190 tonnes/hour. It corresponds to 20 BPM with water and 10 BPMwith cement at 16.7 ppg (2 sgu) density. The maximum pressure is 725 psi (50 bars).

    Figure 1: NRD Flow Tubes

  • Section One Non Radioactive Densitometer NRDPrinciple Operators & Maintenance Manual

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    1.1 NRD Density Measurement Principle

    The density measurement is based on a mechanical principle. The vibrating tubesprinciple where the resonant frequency is directly proportional to the density of theflowing fluid. Therefore the density measurement is independent of the chemicalcomposition of the cement slurry and no selection curve or special calibration isrequired to provide an accurate density measurement.

    The theory of operation can be modeled as a spring and mass assembly (Figure 2).Once placed into motion, the spring and mass assembly will vibrate at its resonantfrequency. The Coriolis sensor is also vibrating at its resonant frequency that isdirectly related to fluid density.

    Spring & Mass Assembly

    fKM

    == 12pp

    rrpp

    == --K

    Vf

    MtubeV4 2 2

    Where f = Resonant Frequency

    K = spring constant

    M = mass (Fluid + tube)

    Mtube = mass of the empty tube

    V = volume of the tubes

    r = density of the fluid

    Figure 2: NRD Density Measurement Principle

  • Non Radioactive Densitometer NRD Section OneOperators & Maintenance Manual Principle

    Revision AB 5Schlumberger

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    1.2 NRD Flow Rate Measurement Principle

    More than a densitometer, the NRD is also a flowmeter. The mass flowmeasurement is based on the Coriolis effect. The flowing fluid into the vibrating tubescreates a Coriolis force F that is perpendicular to the flow direction (Figure 3). Thiscauses the tube to twist. The Coriolis force and therefore the twist is measured bythe two Pick-Off Coils (Figure 1) and is directly proportional to the mass flow rate M n.

    F Mwxv= -2where: F is the Coriolis Force

    M is the mass of the Fluidw is the vibration angular velocityv is the Flow velocity

    Figure 3: NRD Flow Measurement Principle

    The density and mass flowrate are two direct and independent measurements. Thevolumetric flowrate is the mass flowrate divided by the density of the fluid.

    A resistance temperature device (RTD) welded on the flow tubes compensates thetemperature effect on flowtube properties (i.e., Stiffness) for both density and flowmeasurements. It also measures the temperature of the fluid.

    Three measurements are therefore provided by the NRD: Density, Flow (rate & total)and Temperature.

  • Section One Non Radioactive Densitometer NRDPrinciple Operators & Maintenance Manual

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  • Non Radioactive Densitometer NRD Section TwoOperators & Maintenance Manual Performances

    Revision AB 7Schlumberger

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    2.0 PERFORMANCES

    2.1 Performance Specification

    Density rate: 5 to 25 ppg (0.6 sgu to 3 sgu)

    Flow Rate: 0 to 190 tonnes/hou r (420 000 lbs/hour)0 to 20 BPM with water0 to 10 BPM with cement at 16. 7 ppg (2 sgu) density

    Temperature: -25 C to + 75C (- 13F to + 167F) for the DS 300S Sensor andthe RFT 9712 Electronic

    2.2 Accuracy

    Density: 0.06 +/- 0.06 ppg (0.008 +/- 0.008 sgu) relative to the MudBalance0.04 +/- 0.03 ppg (0.005 +/- 0.004 sgu) relative to the LaboratoryMeasurement

    Flow: +/- 0.5 % of the reading value

    Temperature: +/- 1 deg C

  • Section Two Non Radioactive Densitometer NRDPerformances Operators & Maintenance Manual

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  • Non Radioactive Densitometer NRD Section ThreeOperators & Maintenance Manual Mounting and Mechanical Connections

    Revision AB 9Schlumberger

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    3.0 MOUNTING AND MECHANICAL CONNECTIONS

    3.1 Mounting

    The NRD will replace the Upstream Radioactive Densitometer manufactured byRONAN. Engineering files have been designed for the NRD retrofit on the CPS 361& 362, CBS 062 (VIP Mixer), CPT 311 and CPT 371.

    CPS 361 & 362 PN 919411000CPT 311 PN 538856000CPT 371 PN 538857000CBS 062 PN 960658000

    For mounting the NRD on other units, the following rules should be respected for thebest results: The NRD is a low pressure sensor (51 bars, 740 psi) and therefore should be

    installed in-line on the low pressure piping. It should always be positionedon the suction side of the TRIPLEX pump.

    The NRD needs a minimum downstream pressure (i.e., 15 psi) to operate. The

    correct positions are at the discharge of the VIP Mixer or the 5X6 centrifugalpump and before the discharge valve of the pump (Figure 4).

    Flow Measurement: The NRD should be positioned between the 5x6 centrifugal

    pump and the suction of the Triplex pump with no intermediate batch tank (Figure4).

    3.2 Mechanical Connections

    Minimizing pipe stress and external vibration on the sensor is critical. The followinginstructions should be applied carefully:

    Align the piping and install the sensor in-line using proper connection face to facedimensions.

    The piping should be attached or clamped to a stable structure at two locations:

    one upstream and one downstream from the sensor (Figures 4 and 5). The 4"STAUF connections (PN 962084000) are recommended because they minimizethe vibrations from the chassis.

    If the piping exhibits high vibrations, use flex connections or expander as those

    manufactured by Proco (PN 556565000-3 in. and 556566000-4 in.) to minimizevibration transmission into the sensor.

  • Section Three Non Radioactive Densitometer NRDMounting and Mechanical Connections Operators & Maintenance Manual

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    3.3 Orientation

    Although the sensor orientation does not affect operation, the sensor should bemounted in a vertical line as a flag (Figure 4). This position will ensure a selfflushing of the flowtubes when the piping is purged and, therefore, avoidthe risk of cement setting inside the sensor tubes. This also should preventslug of air from being trapped in the sensor tubes, creating an inaccurate flow rateand density reading.

    3.4 NRD For Acidizing Mounting

    According to Dowells specification, NRD for acidizing (PN 550072000), NRD (stdNRD PN 550070000 or NRD zone 2, PN 550077000) is now delivered with two 1/2NPT nipples welded on the sensor case and a Swagelok relief valve rated to 10 psi(model SS-8CP2-10). While used for acidizing, the NRD must be equipped with thisrelief valve screwed on the nipple. It is located on the ground side of the sensorcase, with the sensor in flag position and the flow through the sensor going from thebottom to the top. This valve is located close to the sensor inlet. It must be extendedby a flexible hose directed towards the ground to prevent fluid projections.

    If for any reason the sensor cannot be installed in flag position (reverse or horizontal),the relief valve will be screwed on the nipple located at the lowest point of the sensorcase. This will allow draining the fluid that could be present inside the sensor case.In all cases, a flexible hose must be screwed on the relief valve outlet. Ensure thelength of this hose is long enough to have the hose outlet close to the ground and in asafe area.

    This relief valve provided with the NRD is intended to prevent acid projection in casesof corroded flow tubes leading to fluid invasion and potential overpressurization of thesensor case (refer to safety warning sent by FES and dated November 16, 1993).

    While removing plugs or relief valve from the sensor case, dirt, moisture, rust or othercontaminants can be introduced into the sensor case. Repurging with dry inert gas(30 minutes purging time at 40 cft/hr of dry inert gas - Argon or Nitrogen) should beperformed to protect internal components from corrosion. This is according to theRepurging a Micro Motion Sensor case Micromotion procedure given in theappendix.

  • Non Radioactive Densitometer NRD Section ThreeOperators & Maintenance Manual Mounting and Mechanical Connections

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    Figure 4: NRD Mounting In Flag Position

  • Section Three Non Radioactive Densitometer NRDMounting and Mechanical Connections Operators & Maintenance Manual

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    When the flag position is not possible, the sensor should be installed caseupward (Figure 5) and BOTH the upstream and downstream valves must be openedto purge the sensor tubes as shown in Figure 6.

    DDNOTE

    AFTER EACH JOB, DON'T FORGET TO FLUSH THE SENSOR TUBEWITH CLEAN WATER AND TO PURGE IT. ANY CEMENT SETTING ORWATER FREEZING WOULD DAMAGE THE SENSOR.

    Figure 5: NRD Mounting On A Horizontal Piping

  • Non Radioactive Densitometer NRD Section ThreeOperators & Maintenance Manual Mounting and Mechanical Connections

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    Figure 6: Flushing the NRD Mounted On A Horizontal Piping

  • Section Three Non Radioactive Densitometer NRDMounting and Mechanical Connections Operators & Maintenance Manual

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  • Non Radioactive Densitometer NRD Section FourOperators & Maintenance Manual Electrical Connections

    Revision AB 15Schlumberger

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    4.0 ELECTRICAL CONNECTIONS

    4.1 Sensor To The RFT 9712

    Wiring connections from the sensor to the RFT are made within the supplied bluejunction box. This is not attached to the sensor when shipped.

    Attach and position the blue junction box on the sensor manifold as desired.

    Unscrew the junction box cover to access the 9 positions terminal strip. Wiringinstructions are shown on Figure 7.

    Refer to these directions when making connections to the transmitter RFT 9712.

    DDWARNING

    Make sure power is off during connection of power supply wiring. Power supply voltage must be between 12 and 30 VDC, 6.5 watts is

    typical, and 14 watts maximum. If power supply drops below 11VDC, the sensor will not be working.

    The minimum start up current should be 1 Amp.

    DDNOTE

    The blue cable between the Sensor and the electronics RFT 9712 should beprepared according to the Instructions shown in the Appendix 6.

  • Section Four Non Radioactive Densitometer NRDElectrical Connection Operators & Maintenance Manual

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    Figure 7: Wiring Connections Sensor to RFT 9712

  • Non Radioactive Densitometer NRD Section FourOperators & Maintenance Manual Electrical Connections

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    4.2 Electronic RFT 9712 to the J-BOX (PACR)

    Figure 8: Wiring Connections RFT 9712 to J-BOX (PACR)

    4.3 RFT 9712 To The ECM Of The VIP Mixer

    The NRD wiring connection are described in the VIP Maintenance Manual PN016632000.

  • Section Four Non Radioactive Densitometer NRDElectrical Connection Operators & Maintenance Manual

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  • Non Radioactive Densitometer NRD Section FiveOperators & Maintenance Manual Start Up

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    5.0 START UP

    5.1 Power On

    After the sensor and transmitter have been correctly connected, power can beapplied. Let the water run through the sensor for about 5 minutes to stabilize fluidand sensor temperature. The LED indicator flashes at a rate of 1 Hz (on 25% of thetime, off 75% of the time) to indicate normal operation. The star on the display of theRFT 9712 interface flashes at the inverse duty cycle (on 75% of the time, off 25% ofthe time to indicate normal operation).

    5.2 Meter Zero

    This procedure should be done after the first NRD installation on the unit in order tocompensate a small twist on the sensor tubes. This twist is due to the stress on theflanges during the mounting. This small twist, without flow, induces an error at lowflowrate.

    After the first installation, zeroing the meter needs to be done. Perform this with theflowtubes full of water, under no flow conditions.

    Procedure

    Close the discharge valve downstream of the sensor and continue pumping water toensure that the sensor is completely filled with water. The RFT should display thedensity of water, 8.33 ppg (0.9982 g/cm3).

    DDWARNING

    Fluid flow through the sensor must be completely stopped or the zeroflow setting will be incorrect. Problems setting zero flow occasionallyoccur because of leakage through valves

    The RFT 9712 can be zeroed in three ways: 1) with the internal set zero switch, 2)with a remote set zero switch wired across terminal 14 and 15 (Figure 9), and 3) withan auto zero command from the 268 interface.

    The LED in the terminal compartment (Figure 9) turns on after 2 seconds of zeroswitch closure and remains on continuously during calibration of zero flow.

    Zeroing takes between 45 and 80 seconds depending on the fluid density present inthe flow tube during this procedure. Be sure this procedure is completed beforestarting flow to avoid miscalibration, wrong density and flowrate measurements. Afterthe zeroing procedure has been completed, the LED will flash at a rate of 1 Hz.

  • Section Five Non Radioactive Densitometer NRDStart Up Operators & Maintenance Manual

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    Figure 9: RFT 9712 Terminal Compartment

  • Non Radioactive Densitometer NRD Section FiveOperators & Maintenance Manual Start Up

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    If auto zeroing fails, the LED will flash at a rate of 4 Hz to indicate an error condition.An auto zero error condition could signify that:

    An excessive fluid is still flowing. The sensor tubes are not completely full (density lower than 8.1 ppg or 0.97 g/cm3

    with water). The sensor is improperly mounted.

    To clear an auto zero error, perform another auto zero after correcting theproblem or turn power off, then on again.

    5.3 Flow Totalizer

    The totalizer reset button (only on the RFT equipped with local display) resets theinternal flow totalizer of the RFT 9712 as well as the total flow shown on the display.

    Operation:

    Push the button less than 2 seconds to stop the totalization. Push the button less than 2 seconds to restart the totalization. Push the button more than 2 seconds to reset the total flow.

    5.4 PACR And PPR Configurations

    The RFT 9712 has been configured when shipped as following:

    Density (lb/gal) 4 mA = 5 lb/gal = 0.6 g/cm320 mA = 25 lb/gal = 3 g/cm3

    Flow Rate (gal/mn) 0 Hz = 0 gal/mn = 0 l/mn1000 Hz = 840 gal/mn = 3180 l/mn

    The Density/Current Output equation when density unit is Ib/gal:

    Density (lb/gal) = A x Current (mA) + B

    In this configuration A = 1.25 and B = 0

    If the job design is at 16.2 lb/gal density and the operator wants to check if the PACRor PPR reading is correct, send 12.96 mA to the PACR or PPR with the 268 interfaceusing successively the keys Test, Loop Test, Output, Others (see Appendix 3).

  • Section Five Non Radioactive Densitometer NRDStart Up Operators & Maintenance Manual

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    The Density/Current Output equation when density unit is g/cm3:

    Density (g/cm3) = A x Current (mA) + B

    In this configuration A = 0.15 and B = 0

    If the job design is at density 2 g/cm3 and the operator wants to check if the PACR orPPR reading is correct, send 13.33 mA to the PACR or PPR with the 268 interfaceusing successively the keys Test, Loop Test, Output, Others (see Appendix 3).

    The Flow K Factor equation when Flow Unit is gal/mn

    K (mBL/pulse)= (3785 x Maximum Flow Rate in gal/mn)(Frequency in Hz x 159 x 60)

    The Flow K Factor equation when Flow Unit is l/mn

    K (mBL/pulse)= Maximum Flow Rate (in gal/mn)(Frequency in Hz x 159 x 60)

    With the previous RFT 9712 configuration, the PACR or PPR should be configured asfollows:

    Density (lb/gal) 2 Volts = 5 lb/gal and 10 Volts = 25 lb/gal or0 Volts = 0 lb/gal and 10 Volts = 25 lb/gal

    Flow K factor (mBL/pulse) = 0.333

  • Non Radioactive Densitometer NRD Section FiveOperators & Maintenance Manual Start Up

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    5.5 Valves Configuration During Density Build Up and Pumping

    The NRD is a mass flowmeter and therefore the sensor measures continuously theflow and the density of the process fluid. The NRD is always mounted on aconfiguration that allows the Density measurement during the build-up, density andflow rate during pumping operation.

    Figure 10: Density Build-Up Configuration

    In this configuration (Figure 10) the NRD measures the density during the build-up.When the density design is reached and the operator is ready to pump, the valvesshould be switched to the following positions (Figure 11). This will enablemeasurement of both density and flowrate during pumping operation.

  • Section Five Non Radioactive Densitometer NRDStart Up Operators & Maintenance Manual

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    Figure 11: Pumping Configuration

  • Non Radioactive Densitometer NRD Section SixOperators & Maintenance Manual Calibration

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    6.0 CALIBRATION

    The NRD density and flow measurement principles, as shown in Part 1, areindependent of slurry composition. Therefore no pre-job calibration is required. Inorder to compensate the erosion inside the sensor tubes, the density and flowcalibration needs to be done when the accuracy does not meet the specification(approximately each 200 hours of operation).

    The density and flow calibration should be performed by an electronictechnician with the Smart Communication Interface 268 or Prolink PCInterface (PN 550076000 (110 VAC) or PN 560707000 (220 VAC)).

    The initial density and initial flow calibration factors inside the RFT memoryshould match those on the data tag attached to the sensor.

    DDNOTE

    The 268 or Prolink PC is a Smart Communication Interface which allows theuser to change the flow and density calibration factors when the RFT 9712is used with another sensor or when the sensor needs recalibration.

    See the instruction manual entitled Using the SMART FAMILY Interface268 with the Micro Motion Remote Flow Transmitter, Section 3.10 forinformation on use the 268 Interface/Prolink PC Interface for changing flowand density calibration factors. A load resistance of 250 to 1000 Ohmsmust be present on the 4-20 mA output loop to enable use of 268Interface/Prolink PC Interface.

    6.1 Density Calibration Factor Determination

    The density calibration factor contains three terms (see below). The first term is thenatural period of the sensor tube when filled with air (sensor empty) at 0C. Thesecond term (shown in bold face type) is the natural period of the sensor tube whenfilled with water at 0C. The third term is the temperature coefficient of the modulus ofelasticity of the sensor and is therefore dependent on the sensor material. For 316Lstainless steel sensors, this value is 4.44%/100C. For Hastelloy-C, this value is2.75%/100C.

    11483124634. 44

    The RFT can automatically determine terms one and two through its operatingsoftware using the following procedure. Jumper locations on the microprocessorboard (Figure 12), in conjunction with the SET ZERO switch, allow detection of tubeperiod using air and tube period using water, adjusting them mathematically using thesensed temperature.

  • Section Six Non Radioactive Densitometer NRDCalibration Operators & Maintenance Manual

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    DDNOTE

    If the density offset is lower than 0.3 lb/gal or 0.04 g/cm3, then only the 268Interface is necessary to correct the density calibration factor as describedin STEP 3.

    Procedure

    STEP 1: The sensor tubes should be dry and only air is present in the tubesbefore starting the Air Calibration. If the pipe is not clean rinse with water andblow out the sensor with air so that only air is present in the tubes. Install the jumperas shown below:

    Figure 12: Jumper Orientation

    With the meter operating, press the SET ZERO switch and hold it down until the LEDindicator stays on. When the LED starts to flash again, the natural period using airhas been recorded and stored in the transmitter memory. Remove the Jumper.

  • Non Radioactive Densitometer NRD Section SixOperators & Maintenance Manual Calibration

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    STEP 2: Fill the sensor flow tube with room temperature water making sure that thetube is completely filled. Wait 10 minutes in order to reach thermal equilibriumbetween the sensor tubes and the water. Install the Jumpers as shown below:

    With the meter operating, press the SET ZERO switch and hold it down until the LEDindicator stays on. When the LED starts to flash again, the natural period using waterhas been recorded and stored in the transmitter memory. Remove the jumpers.

    STEP 3: At this step, the density calibration factor can be fine tuned. The naturalperiod of the tube, which has been recorded at 0 C, should be corrected at roomtemperature. Attach the 268 Interface/Prolink PC Interface and turn it on. If it isalready attached, restart the 268 Interface/Prolink PC Interface to read in the newvalue for the density calibration factor. Use the Process Variable Function to read thewater density and the temperature. Appendix 2 gives the water density versustemperature. Correct the water period (shown in bold face type) of the densitycalibration factor to match the water density value at room temperature given inAppendix 2.

  • Section Six Non Radioactive Densitometer NRDCalibration Operators & Maintenance Manual

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    Example:

    11483124634. 44

    A NRD with a density calibration factor of 11483 124634. 44 is being recalibrated.The sensor is full of water and the thermal equilibrium between the tube and waterhas been reached.

    The density displayed by the RFT 9712 is 0.9945 g/cm3 and the water temperatureis 26C. The Appendix 2 shows a water density of 0.9966 g/cm3 at 26C. Thewater period (shown in bold face type) of the density calibration factor should bechanged with the 268 Interface/Prolink PC Interface to 12461 instead of 12463. Thedisplay shows the correct water density of 0.9966 g/cm3 at 26 C.

    The density displayed by the RFT 9712 is 0.9985 g/cm3 and the water temperatureis 26C. Appendix 2 shows a water density of 0.9966 g/cm3 at 26C. The waterperiod (shown in bold face type) of the density calibration factor should be changedwith the 268 interface to 12465 instead of 12463. The display shows the correctwater density of 0.9966 g/cm3 at 26 C.

    6.2 Flow Calibration Factor Determination

    The flow calibration factor contains two terms. The first term is the sensitivity,expressed in grams/sec, mass flow rate necessary to produce 1 microsecond of deltatime from the sensor at 0 C. The second term (shown in bold face type) of the flowcalibration factor, is the temperature coefficient of the modulus of rigidity of the sensortube material and is therefore dependent on the tube material. For 316L stainlesssteel sensors, this value is 5.13%/100 C. For Hastelloy C, this value is 3.15%/100 C.The complete flow calibration factor is expressed as follows:

    467.275.13

    Where 467.27 = the sensitivity and 5.13 = temperature coefficient.

    The flow calibration factor can be fine tuned using a reference electromagneticflowmeter or a batch tank.

  • Non Radioactive Densitometer NRD Section SixOperators & Maintenance Manual Calibration

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    Procedure

    After zeroing the meter, a batch should be run with water near the maximum flowrate. The reference value should be compared to the RFT 9712 total display ortotalized frequency output. The flow calibration factor should be adjusted either up ordown using the following equation:

    New Flow calibration factor = Old Flow calibration factor x TOTAL referenceTOTAL meter

    Example:

    An NRD model DS300S sensor having a flow calibration factor of 467.275.13 is beingrecalibrated. The results of the batch run is 5050 kg or litres of water and the flowtotalizer reads 5000 kg or litres.

    New Flow calibration factor = 467.27 x 5050 = 471. 94 5000

    New Flow calibration factor = 471.94 5.13

    Only the first five digits are recalculated. The last three digits are the temperaturecoefficient and should not be modified.

  • Section Six Non Radioactive Densitometer NRDCalibration Operators & Maintenance Manual

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    DENSITOMETER NON-RADIOACTIVE NRD OP & MAINT TABLE OF CONTENTS1.0 PRINCIPLE1.1 NRD Density Measurement Principle1.2 NRD Flow Rate Measurement Principle2.0 PERFORMANCES2.1 Performance Specification2.2 Accuracy

    3.0 MOUNTING AND MECHANICAL CONNECTIONS3.1 Mounting3.2 Mechanical Connections3.3 Orientation3.4 NRD For Acidizing Mounting

    4.0 ELECTRICAL CONNECTIONS4.1 Sensor To The RFT 97124.2 Electronic RFT 9712 to the J-Box (PACR)4.3 RFT 9712 To The ECM Of The VIP Mixer

    5.0 START UP5.1 Power On5.2 Meter Zero5.3 Flow Totalizer5.4 PACR And PPR Configurations5.5 Valves Configuration During Density Build Up and Pumping

    6.0 CALIBRATION6.1 Density Calibration Factor Determination6.2 Flow Calibration Factor Determination

    7.0 TROUBLE SHOOTING7.1 LED Fault Indications7.2 Failure Symptoms and Trouble Shooting Procedure7.2.1 Power Failure:7.2.2 Density Offset:7.2.3 Major Failure:

    8.0 USING THE SMART COMMUNICATION INTERFACE MODEL 2688.1 268 Connections8.2 Operation Diagram8.3 PC Based Programmer

    9.0 SPARE PARTS LISTNON RADIOACTIVE DENSITOMETER NRD OPERATORS & MAINTENANCE MANUAL Appendix 1: Exploded DrawingAppendix 2: Temperature and Density of WaterAppendix 3: 268 Interface Operation DiagramAppendix 4: RFT 9712 Configuration RecordAppendix 5: NRD Failure ReportAppendix 6: RFT 9712 to Sensor cable Preparation InstructionAppendix 7: DS300S DimensionsAppendix 8: Equipment Selection Form