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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
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Non Radioactive Densitometer NRDTable of Contents Operators
& Maintenance Manual
2 Revision ABSchlumberger
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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
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SchlumbergerDowell
NON RADIOACTIVE DENSITOMETERNRD
OPERATORS & MAINTENANCEMANUAL
PN 962095000 AB
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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
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Section One Non Radioactive Densitometer NRDPrinciple Operators
& Maintenance Manual
4 Revision ABSchlumberger
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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
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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.
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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
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Section Two Non Radioactive Densitometer NRDPerformances
Operators & Maintenance Manual
8 Revision ABSchlumberger
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Non Radioactive Densitometer NRD Section ThreeOperators &
Maintenance Manual Mounting and Mechanical Connections
Revision AB 9Schlumberger
Dowell
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.
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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.
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Non Radioactive Densitometer NRD Section ThreeOperators &
Maintenance Manual Mounting and Mechanical Connections
Revision AB 11Schlumberger
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Figure 4: NRD Mounting In Flag Position
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Section Three Non Radioactive Densitometer NRDMounting and
Mechanical Connections Operators & Maintenance Manual
12 Revision ABSchlumberger
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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
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Non Radioactive Densitometer NRD Section ThreeOperators &
Maintenance Manual Mounting and Mechanical Connections
Revision AB 13Schlumberger
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Figure 6: Flushing the NRD Mounted On A Horizontal Piping
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Section Three Non Radioactive Densitometer NRDMounting and
Mechanical Connections Operators & Maintenance Manual
14 Revision ABSchlumberger
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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.
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Section Four Non Radioactive Densitometer NRDElectrical
Connection Operators & Maintenance Manual
16 Revision ABSchlumberger
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Figure 7: Wiring Connections Sensor to RFT 9712
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Non Radioactive Densitometer NRD Section FourOperators &
Maintenance Manual Electrical Connections
Revision AB 17Schlumberger
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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.
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Section Four Non Radioactive Densitometer NRDElectrical
Connection Operators & Maintenance Manual
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Non Radioactive Densitometer NRD Section FiveOperators &
Maintenance Manual Start Up
Revision AB 19Schlumberger
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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.
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Section Five Non Radioactive Densitometer NRDStart Up Operators
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Figure 9: RFT 9712 Terminal Compartment
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Non Radioactive Densitometer NRD Section FiveOperators &
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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).
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Section Five Non Radioactive Densitometer NRDStart Up Operators
& Maintenance Manual
22 Revision ABSchlumberger
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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
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Non Radioactive Densitometer NRD Section FiveOperators &
Maintenance Manual Start Up
Revision AB 23Schlumberger
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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.
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Section Five Non Radioactive Densitometer NRDStart Up Operators
& Maintenance Manual
24 Revision ABSchlumberger
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Figure 11: Pumping Configuration
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Non Radioactive Densitometer NRD Section SixOperators &
Maintenance Manual Calibration
Revision AB 25Schlumberger
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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.
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Section Six Non Radioactive Densitometer NRDCalibration
Operators & Maintenance Manual
26 Revision ABSchlumberger
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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.
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Non Radioactive Densitometer NRD Section SixOperators &
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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.
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Section Six Non Radioactive Densitometer NRDCalibration
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28 Revision ABSchlumberger
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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.
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Non Radioactive Densitometer NRD Section SixOperators &
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Revision AB 29Schlumberger
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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.
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Section Six Non Radioactive Densitometer NRDCalibration
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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