Schlumberger Engineer Guide (MWD/LWD)

MWD / LWD Engineer Guide (Grade 9)

Tatiana A. Silva

Schlumberger

Engineer Guide (Grade 9)

Dez - 2006

INDEX

1.

DRILLING FLUIDS............................................................................................................................5 1.1. 1.2. 1.3. 1.4.

2.

PORE PRESSURE ..............................................................................................................................6 2.1. 2.2.

3.

FUNCTIONS................................................................................................................................... 5 PROPERTIES .................................................................................................................................. 5 PRESSURE LOSS............................................................................................................................ 5 SOLID CONTROL EQUIPMENT ....................................................................................................... 5

SURFACE INDICATION OF OVERPRESSURE .................................................................................... 6 HYDROSTATIC PRESSURE ............................................................................................................. 6

DRILL STRING ..................................................................................................................................7 3.1. DRILL BITS ................................................................................................................................... 7 3.2. BHA - BOTTOM HOLE ASSEMBLY ............................................................................................... 7 3.2.1. Drill Collar ............................................................................................................................. 7 3.2.2. Heavy-weight Drill Pipe ......................................................................................................... 7 3.2.3. Stabilizers ............................................................................................................................... 7 3.2.4. Roller Reamers ....................................................................................................................... 8 3.2.5. Bit Sub .................................................................................................................................... 8 3.2.6. UBHO Subs ............................................................................................................................ 8 3.2.7. Pony / Short Drill Collars....................................................................................................... 8 3.2.8. MWD / LWD Tools ................................................................................................................. 8 3.2.9. Jars ......................................................................................................................................... 8 3.2.10. Circulation Subs ................................................................................................................ 8 3.2.11. Hole Openers ..................................................................................................................... 8 3.3. DRILL PIPE ................................................................................................................................... 8 3.4. NEUTRAL POINT ........................................................................................................................... 9 3.5. BUOYANCY FACTOR .................................................................................................................... 9 3.6. CONNECTIONS .............................................................................................................................. 9

4.

SENSORS ...........................................................................................................................................10

5.

ETHERNET .......................................................................................................................................11 5.1. 5.2.

6.

TROUBLESHOOTING ....................................................................................................................12 6.1. 6.2. 6.3.

7.

TOPOLOGIES ............................................................................................................................... 11 SETTING NAME CONFIGURATION ................................................................................................ 11

PROBLEMS.................................................................................................................................. 12 STEPS ......................................................................................................................................... 12 PSAM / ASAP ........................................................................................................................... 12

D&I .....................................................................................................................................................13 7.1. WELL PROFILES ......................................................................................................................... 13 7.2. UTM GRID SYSTEM ................................................................................................................... 14 7.3. WELL PLOTS .............................................................................................................................. 15 7.4. SURVEYS .................................................................................................................................... 15 7.4.1. Components .......................................................................................................................... 15 7.4.2. Surveying Tools .................................................................................................................... 15 7.5. INCLINATION .............................................................................................................................. 16 7.6. AZIMUTH.................................................................................................................................... 16 7.7. TOOL-FACE ................................................................................................................................ 17 7.8. D&I DATA USAGE ...................................................................................................................... 17 7.9. FE RESPONSIBILITIES ................................................................................................................. 18

Tatiana A. Silva

2


Dez - 2006

7.9.1. Pre-Run................................................................................................................................. 18 7.9.2. BHA P/up.............................................................................................................................. 18 7.9.3. IDEAL................................................................................................................................... 18 7.9.4. Job Execution ....................................................................................................................... 18 7.10. TAKING A SURVEYS ................................................................................................................... 19 7.10.1. Procedures ....................................................................................................................... 19 7.10.2. Field Acceptance Criteria – FAC .................................................................................... 19 7.10.3. Roll Test ........................................................................................................................... 19 7.11. SURVEY OUT OF FAC ................................................................................................................. 20 7.11.1. G out of FAC.................................................................................................................... 20 7.11.2. H or Dip Out of FAC ....................................................................................................... 20 7.11.3. 5-Axis Correction............................................................................................................. 20 7.11.4. D-Mag.............................................................................................................................. 20 7.12. DRILLSTRING MAGNETIC INTERFERENCE................................................................................... 21 8.

MWD TELEMETRY ........................................................................................................................22 8.1. SIGNAL GENERATION ................................................................................................................. 22 8.2. MODULATORS ............................................................................................................................ 22 8.3. SIGNAL STRENGTH ..................................................................................................................... 22 8.4. DATA ENCODING........................................................................................................................ 23 8.5. SPT’S ......................................................................................................................................... 23 8.6. DATA MODULATION/DEMODULATION ....................................................................................... 24 8.7. BANDWIDTH ............................................................................................................................... 25 8.8. SIGNAL PROBLEMS ..................................................................................................................... 26 8.8.1. Attenuation ........................................................................................................................... 26 8.8.2. Pump Noise........................................................................................................................... 26 8.8.3. Downhole Noise.................................................................................................................... 27 8.8.4. Electrical Noise .................................................................................................................... 28 8.8.5. Echoes and Reflections ......................................................................................................... 28 8.9. HSPM ........................................................................................................................................ 29 8.9.1. Pump Noise........................................................................................................................... 29 8.9.2. Drilling Noise ....................................................................................................................... 30 8.9.3. Motor Stalls .......................................................................................................................... 30 8.9.4. Downhole Noise.................................................................................................................... 31 8.9.5. Electrical Noise .................................................................................................................... 31 8.9.6. Echoes and Reflections ......................................................................................................... 32 8.9.7. MWD Failure........................................................................................................................ 32 8.10. NO SIGNAL ................................................................................................................................. 33 8.10.1. Dark Blue spectrogram.................................................................................................... 33 8.10.2. Pump noise but no tool signal in the telemetry band ....................................................... 33 8.10.3. Tool at a different mode................................................................................................... 33 8.10.4. Low Signal on only 1 SPT................................................................................................ 33 8.10.5. Low Signal on both SPT................................................................................................... 33 8.10.6. SPT-B............................................................................................................................... 33

9.

MWD TOOLS ....................................................................................................................................34 9.1. ALL TOOLS................................................................................................................................. 34 9.2. POWERPULSE ............................................................................................................................. 35 9.2.1. Components .......................................................................................................................... 35 9.2.2. MMA Considerations............................................................................................................ 35 9.2.3. MEA Sub Components .......................................................................................................... 36 9.2.4. MGR – Gamma Ray.............................................................................................................. 36 9.2.5. MTA Considerations............................................................................................................. 37 9.2.6. MDC Considerations ............................................................................................................ 37 9.2.7. IWOB / MVC......................................................................................................................... 37 9.2.8. Some Specifications .............................................................................................................. 38

Tatiana A. Silva

3


Dez - 2006

9.2.9. PPL Jamming ....................................................................................................................... 38 9.2.10. IWOB Calibration............................................................................................................ 39 9.3. TELESCOPE ................................................................................................................................ 39 9.4. DOWNLINK ................................................................................................................................. 40 9.4.1. Legacy................................................................................................................................... 41 9.4.2. Manual Fast.......................................................................................................................... 41 10.

LWD TOOLS .....................................................................................................................................42

10.1. ARC........................................................................................................................................... 42 10.1.1. Some specifications.......................................................................................................... 43 10.1.2. Rt measurement................................................................................................................ 43 10.1.3. Gamma Ray measurement ............................................................................................... 47 10.1.4. ARC 6/7/8 Checklist......................................................................................................... 48 10.1.5. Resistivity Interpretation.................................................................................................. 51 10.1.6. APWD .............................................................................................................................. 52 11.

BIBLIOGRAPHY..............................................................................................................................58

Tatiana A. Silva

4


Dez - 2006

1. Drilling Fluids Water based Mud Oil Based Mud Synthetic based Mud Pneumatic based Mud

WBM OBM SBM PBM

Water or brine as base fluid Crude oil, diesel as base fluid Pseudo oil as base fluid Air, Foam or natural gas as base fluid

1.1. Functions • • • • • •

Control Formation Pressure Hole Cleaning Suspend Solids. Lubrication and cooling of drill string Gathering information Provide Buoyancy

• Transmit power • Prevent corrosion • Stabilization of the exposed rock formation • Minimize formation damage • Isolate fluid from formation

1.2. Properties • • • •

Density (ppg, g/cc, psi/ft) Rheology: Viscosity and Gel Strength Fluid Loss (Filtration) Inhibition

1.3. Pressure Loss

PStdpipe = PSurf.Eq + PDrill String + PMWD/Motor + PBit + PAnnulus 1.4. Solid Control Equipment • • • • •

Shale Shaker Degasser Desander Desilter Mud Cleaner

Tatiana A. Silva

5


Dez - 2006

2. Pore Pressure 2.1. Surface Indication of Overpressure • • • • • •

Increase in background and connection gas. Gas Ratio C2/C3. Increase in ROP. Presence of splintered cavings at the shakers. Increase in torque and Drag. Reduction in return mud weight.

2.2. Hydrostatic Pressure Hydrostatic Pressure = 0.052 x Mud Weight (ppg) x TVD (ft)

Tatiana A. Silva

6


Dez - 2006

3. Drill String 3.1. Drill Bits Drill Bits

Roller Cone Bits

By Cutting Structure

Milled Tooth Bits

Fixed Cutter Bits

By Bearing System

Insert Bits

Roller Bearing

Milled Tooth

Journal Bearing

Insert

PDC bits

Natural Diamond

PDC

Diamond Bits

TSP

Impregnated Bits

Natural Diamond

3.2. BHA - Bottom Hole Assembly 3.2.1. Drill Collar • Provide weight • Slick Collars / Spiral Drill Collar 3.2.2. Heavy-weight Drill Pipe • Standard / Spiral 3.2.3. Stabilizers • Integral Blade • Sleeve and Mandrel

Tatiana A. Silva

• Welded Blade • Clamp-On

7


Dez - 2006

• Straight blades or spiral blades • String(box / pin) or Near Bit (box / box) types 3.2.4. Roller Reamers • Substitute for Stabilizers • ONLY run in the BHA between Drill Collars 3.2.5. Bit Sub • It is used when a Near Bit Stabilizer is not required • It can be used to contain one of the following: Float Valve Survey Baffle / Totco Ring 3.2.6. UBHO Subs 3.2.7. Pony / Short Drill Collars 3.2.8. MWD / LWD Tools 3.2.9. Jars 3.2.10.

Circulation Subs

3.2.11.

Hole Openers

HOLE SIZE 36” – 22” 16” – 17 ½” 12 ¼” – 12” 9 7/8” – 8” 6 ¼” – 5 7/8” 5 ½” – 4”

COLLAR SIZE 14 “ – 9 ½” 9 ½” – 8” 8 ¼” – 7 ¾” 6 ¾” – 6 ½” 4 ¾” 3 ½”

TOOL SIZE 11” 9 ½” 8 ¼” 6 ¾” 4 ¾” -

3.3. Drill Pipe

Tatiana A. Silva

8


Dez - 2006

3.4. Neutral Point • Tension = 0 • Stress = 0 3.5. Buoyancy Factor BuoyancyFactor = 1 −

MudWeight ( ppg ) 65.5

BuoyancyWeight = BuoyancyFactor × AirWeight AvaibleWeight = BuoyancyWeight × Cos (θ )

3.6. Connections • For Collars we simply call it a “Connection” • For Drill Pipe it is called a “Tool Joint” Making a Connection: • • • • • •

Keep it dry / clean Apply Dope Stab Tong Placement Screw in Torque

Tatiana A. Silva

9


Dez - 2006

4. Sensors SENSORS Hookload Pump pressure SPT-FA

INPUT

OUTPUT

PSAM

ASAP

WIRES

24 V

4 – 20 mA

2 – 10 V

1–5V

V S+

Torque

24 V

0–3V

0–6V

0–3V

SPT-BE

24 V

6V

6V

6V

SPT-HA

24 V

7V

7V

7V

Depth Encoder

12 V

5V

5V

5V

Pump Stroke

12 V

12 V

5V

5V

V S+ Gnd V S+ SGnd V S+ SGnd Spare V S+ SGnd V S+

Calibration:

Tatiana A. Silva

10


Dez - 2006

5. Ethernet 5.1. Topologies • Bus (serially) • Star (IEH – IDEAL Ethernet Hub) 5.2. Setting name configuration Start → Ideal Utilities → W2KNetConfig Name IDEAL1 IDEAL2 HSPM1 HSPM2 IRCT ICPC

Tatiana A. Silva

Node ASLAV1 ASLAV2 ASLAS1 ASLAS2 ASLAX1 ASLAX2

IP Address 163.185.21.30 163.185.21.31 163.185.21.32 163.185.21.33 163.185.21.34 163.185.21.35

11


Dez - 2006

6. Troubleshooting 6.1. Problems • • • • •

Sensor related Junction Box Related Cabling related PSAM / ASAP related HSPM related

6.2. Steps • • • •

Stop. Assess the situation. Make a plan Do not leave the unit (assuming the cables are connected) Focus your attention on the PSAM / ASAP Trace the problem one step at a time

6.3. PSAM / ASAP • • • • •

Check for correct wiring Check Jumper settings Check fuses Check barriers Check voltages

Tatiana A. Silva

12


Dez - 2006

7. D&I 7.1. Well Profiles

Straight Well (Vertical)

S-Type Well

Slant Well (J-Type)

Horizontal Well

Tatiana A. Silva

13


Dez - 2006

7.2. UTM Grid System • Divides world into 60 equal longitudinal zones (6 deg wide each) • UTM Grid Reference include: Zone Number + Hemisphere (N/S) • Range of Eastings are: ~200,000m → ~800,000

3°

Tatiana A. Silva

3°

14


Dez - 2006

7.3. Well Plots

Displacement East/West

Plane of Proposal

Target Section Horizontal Displacement (HD)

Displacement North/South Plane of Proposal Angle

Closure Angle

Surface Reference Point

7.4. Surveys 7.4.1. Components • Measured Depth • Inclination • Azimuth 7.4.2. Surveying Tools • Inclination only (TOTCO and AnderDrift) • Inclination & Azimuth • MN Referenced (Single Shot, Multi Shot and MWD) • TN Referenced (Gyro)

Tatiana A. Silva

15


Dez - 2006

7.5. Inclination • • • •

It is the angle of deviation from vector g Tri-Axial Accelerometers 1000 “counts” = 1g Tg is stable (Roll Test)

Tg = Gy 2 + Gz 2

7.6. Azimuth • It is the angle between North Reference and a horizontal projection of wellbore • Tri-Axial Magnetometers • 1 Tool H = 50 Gammas / 1 NanoTesla = 1 Gamma • Magnetic Dip Angle = Cos-1 (HC/H) (HC = horizontal component) • DIP ≅ 90° → Close to Poles / DIP ≅ 0° → Close to Equator • Th is stable (Roll Test)

Th = Hy 2 + Hz 2

• Magnetic declination is the angle between TN and MN measured from TN Final Azimuth = Mag. Az. + Mag. Declination – Grig Conv.

Tatiana A. Silva

16


Dez - 2006

7.7. Tool-Face • Orientate a motor high-side • Low inclination → magnetometers → Magnetic Tool-Face (MTF) • High inclination → accelerometers → Gravity Tool-Face (GTF)

Regular MTF/GTF Switch Low MTF/GTF Switch

MTF Drift < 5° Drift < 2.5 °

GTF Drift > 8° Drift > 3.5 °

Previous 5°< Drift < 8° 2.5 ° < Drift < 3.5°

7.8. D&I Data usage Data

Use

GFH

QA

All G

HFH

QA

All H

DIP

QA

All G, all H

Inclination

Wellpath

All G

Azimuth

Wellpath

All G, all H

MTF

Steering

Gy, Gz, Hy, Hz

GTF

Steering

Gy, Gz

Cont_inc

Steering

Rgx

Gy, Gz

Cont_azi

Steering

Rgx, Rhx

Gy, Gz, Hy, Hz

Tatiana A. Silva

Real-time

Last Survey

Gx, Hx

17


Dez - 2006

7.9. FE Responsibilities 7.9.1. Pre-Run • • • •

Check Calibration of MWD Tool (D&I calibration – 6 months) Check requirements (TN or GN?) Calculate EDI (< 0.5) Program the Tool 7.9.2. BHA P/up

• Measure the Tool-face correction (from ROP to motor scribe line, clockwise, looking downhole) TFC =

ARC × 360 Circ

7.9.3. IDEAL • D&I Inits – Geomag o Inputs: Long, Lat, Date and Elevation o Outputs: Loc G, Loc H, Mag. Dec. and Mag. Dip Angle • Tie In Point • Platform Reference • BHA • DLIS SAVE 7.9.4. Job Execution • SHT o o o o o

Gx ≈ 1000 counts Gy and Gz ≈ 0 Tool G ≈ Loc G Inc ≈ 0 Pay attention: flow rate, standpipe pressure and tur_rpm

• Surveys

Tatiana A. Silva

18


7.10.

Taking a Surveys

7.10.1. • • • • • • • •

Procedures

Off Bottom Stop Rotating Work pipe (to remove trapped torque), last movement up. Stop ALL movement, chain down break. Drop pumps below min flow rate until you see signal loss. Bring pumps up above minimum flow. No pipe movement before the pre-cursor. Complete a written survey record 7.10.2.

• • • •

Dez - 2006

Field Acceptance Criteria – FAC

G = Reference ± 2.5 mg (2.5 counts) H = Reference ± 6 counts (300 nT) Mag Dip = Reference ± 0.45o Inc, Az and DLS are based on the previous surveys 7.10.3.

Roll Test

• 4 rotation surveys taken at the same depth (± 1 meter) • Tg must be constant

Tatiana A. Silva

19


7.11.

Survey out of FAC

7.11.1.

G out of FAC

Possible causes Pipe Movement (erratic G and H) Failed Sensor (accelerometers: 0 or stuck values) Incorrect MWD Calibration 7.11.2. • • • •

Dez - 2006

What should I do Watch the Driller Repeat the survey Roll Test Checkshot or Benchmark Checkshot or Benchmark

H or Dip Out of FAC

Drillstring Magnetism External source Failed Sensor (magnetometers: erratic values) Incorrect MWD Calibration 7.11.3.

5-Axis Correction

• This method can be used in a sensor failure • It is not recommended: o Gy or Gz in vertical holes, o Gx in horizontal holes, o Hy or Hz when drilling North or South with inclination close to magnetic dip angle. o Hx when perpendicular to magnetic dip angle 7.11.4.

D-Mag

• Only Drill string magnetism can be corrected • It is necessary around 10 “good” surveys

Tatiana A. Silva

20


7.12.

Dez - 2006

Drillstring Magnetic Interference

• Acts along the X axis of the tool (effects Hx) • It depends on: • Inclination Horizontal Component (HC) error = Drillstring error * Sin (inclination) • Mag Dip Angle Horizontal Component (HC) = H * Cos (Magnetic Dip Angle) • Direction Error increases when drilling in an east/west direction • BHA

Tatiana A. Silva

21


Dez - 2006

8. MWD Telemetry 8.1. Signal Generation 1) Modulator in open position → mud flows through 2) Modulator in closed position → mud flow is blocked 3) Kinetic energy → pressure 4) Varying the speed of rotation → the frequency changes 5) Slowing down or speeding up for a short period → original frequency → the phase changes 8.2. Modulators PowerPulse

SlimPulse

8.3. Signal Strength • Signal power = (signal strength)2 • Signal energy is signal power x time

Tatiana A. Silva

22


Dez - 2006

Signal Strength

GAP

Erosion GAP

Flow Rate LCM Depth Mud Viscosity Mud Solids * Increased mud weight has the same effect as increased flow rate - they both increase signal strength.

8.4. Data Encoding • Binary Phase Shift Keying • Quadrature Phase shift Keying • Minimum Shift Keying

QPSK MSK SymbolRate = 2(Fa-Fb)

180o 1

No shift 0

BPSQ 0 00

90 01 fc-fb/4 * 0

180 11

270 10 fc+fb/4 * 1

* Where fc is the carrier frequency and fb is the bit rate

• • • •

PowerPulse IMPulse TeleScope SlimPulse

QPSK, BPSK, MSK QPSK, BPSK, MSK QPSK, MSK MSK

12/6 bps 6 bps 48/24 bps 1/0.5 bps

8.5. SPT’s • SPT-H / dynamic output → frequencies from 0.5 to 24Hz • SPT-H / static output → frequencies from 0 to 2 Hz

Tatiana A. Silva

23


Dez - 2006

8.6. Data Modulation/Demodulation Signal → SPT → USP board (ASAP/PSAM) → digital → filters → receiver → binary → frame decoder → data → IDEAL • Data from the MWD tool is sent from downhole as a stream of binary bits. 1’s and 0’s. • A group of 1’s and 0’s is called a WORD. • A WORD can vary in size (typically 2 to 12 bits). • A group of WORDS is called a FRAME. • A Frame is always preceded by a Frame Sync Word and Frame Identification number (FID). Precursor

Survey Frame

Utility Frame

Repeating Frame

Repeating Frame

Precursor: 1 1 1 1 ... 1111 Repeating Pattern

001101011...10 Special Precursor

Survey Frame: Frame Sync

FID

Data

CRC

Utility Frame: Frame Sync

FID

Data

Repeating Frame: Frame Sync

FID

Data

* The survey is taken during the precursor!

Tatiana A. Silva

24


Dez - 2006

8.7. Bandwidth

Bandwidth

Bandpass = Fc ± (0.75 x symbol rate) = Fc ± (0.75 x bit rate / bit/symbol) Fc = Carrier FrequencySignal-to-Noise Ratio

Bit Rate (bps) = Symbol Rate x bits/symbol • If the average SNR is > 15 dB then it is safe to double the bit rate • If the bit rate is doubled then the SNR will drop by at least 3 dB • If the SNR drops below 10 dB → reduce the bit rate

Tatiana A. Silva

25


Dez - 2006

8.8. Signal Problems 8.8.1. Attenuation Factors Mud Viscosity (Max. = 65 cp)

Survey quality

Gas in the Mud Depth Frequency Radiation Loss Flow Rate Pipe ID • The mud viscosity decreases with increasing temperature • Changes in Pipe ID can cause reflex! • WBM – better surveys/SBM – very compressible/OBM – bad surveys 8.8.2. Pump Noise Harmonic =

SPM 60

Information: Flow Rate = FR gpm, the number of pumps is P and a pump gives V gps So… Flow Rate @ each piston =

FR P

SPM = FR @ piston V

Tatiana A. Silva

26


Dez - 2006

SOLUTIONS: • Check the mud conditions (viscosity, gas) • Change the Stroke R • Stagger the pumps (increase the strokes in one and decrease in the other one) • Check the pulsation dampeners (1/3 to ½ of standpipe pressure) • Use Dif. Filter (SPT1 and SPT2 → spacing = ¼ wavelength apart at the carrier frequency) • Pump Noise Canceller • Force retraining • Change band pass • Use notch filter • Try a downlink (telemetry / frequency / bps / FSL) IMPORTANT: If the SPTs are located between 1/8 and 3/8 of a wavelength apart the telemetry waves at each SPT will interfere constructively and result in increased signal strength. Separations of <1/8 wavelength or >3/8 wavelength will cause a reduction in signal strength. c = f × λ (c = speed of sound, f = carrier frequency, λ = wavelength) 8.8.3. Downhole Noise • Bit/Drilling Noise • Rotary Noise • Motor Noise SOLUTIONS: • Change Flow Rate (motor RPM) • Change WOB • Change the motor

Tatiana A. Silva

27


Dez - 2006

8.8.4. Electrical Noise • • • • •

Loose electrical connection Faulty SPT’s Moisture in the AJB Sensor cable near by a power source/cable Ground problems 8.8.5. Echoes and Reflections

• Changes in Pipe ID SOLUTIONS: • Try the Adaptive Equalizer (HSPM) • Use a stronger SPT • Change the SPT position

Tatiana A. Silva

28


Dez - 2006

8.9. HSPM 8.9.1. Pump Noise

Tatiana A. Silva

29


Dez - 2006

8.9.2. Drilling Noise

8.9.3. Motor Stalls

Tatiana A. Silva

30


Dez - 2006

8.9.4. Downhole Noise

8.9.5. Electrical Noise

Tatiana A. Silva

31


Dez - 2006

8.9.6. Echoes and Reflections

Null in telemetry band

8.9.7. MWD Failure

Tool shuts off temporarily

Tatiana A. Silva

32


8.10.

Dez - 2006

No Signal

8.10.1.

Dark Blue spectrogram

• Dead sensor. • Bad connection. • Bad wiring 8.10.2.

• Bad PSAM/ASAP • Bad USP board (Check with loop back connector)

Pump noise but no tool signal in the telemetry band

• Tool Dead 8.10.3.

Tool at a different mode

• Bad configuration • Accidental downlink 8.10.4.

Low Signal on only 1 SPT

• Sensor plugged with dry mud • Bad sensor • Bad position 8.10.5. • • • • • •

Low Signal on both SPT

Washout Tool erosion Mud property changes Flow change Air/gas trapped in mud. Changes of ID in pipes 8.10.6.

• SPT on wrong standpipe (dual standpipe rigs) • Sensors should be on the main flow line • Open or leaking valve in surface piping • Tool with a bypass valve above the MWD tool

SPT-B

• Offset: -150 to 150 psi (DSPScope) • Offset = -250 → non connected SPT-B

Tatiana A. Silva

33


Dez - 2006

9. MWD Tools 9.1. All Tools SlimPulse

IMPulse

PowerPulse

TeleScope

Retrievable

Collar-Based

Collar-Based

Collar-Based

1-3/4” OD

4-3/4” OD

6-3/4”– 9-1/2”OD 6-3/4”– 9-1/2”OD

Battery Powered

Turbine

Turbine

Turbine

35 – 1200 gpm

100 – 400 gpm

225 – 2000 gpm

275 – 2000 gpm

0.1875 – 0.625 Hz 0.25 – 12 Hz

0.75 – 24 Hz

0.75 – 24 Hz

0.5 bps max.

6 bps max.

12 bps max.

48 bps max.

LCM < 50 ppb

LCM < 50 ppb

LCM < 50 ppb

LCM < 50 ppb

Bits Sent

Risk Level

PowerPulse

IMPulse

SlimPulse

1.

2.

Shk>50 G’s

Shk>50 G’s

Shk>50 G’s

0

No Risk

cps < 1

cps < 1

cps < 2

1

Med Risk

1 < cps < 5

1 < cps < 5

2 < cps < 30

2

High Risk

5 < cps < 10

5 < cps < 10

30 < cps < 100

3

Tool Failure Imminent

cps > 10

cps > 10

cps > 100

Tatiana A. Silva

34


Dez - 2006

9.2. PowerPulse • The PowerPulse can measure inclination, azimuth, GTF, MTF, transverse shocks and tool temperature. Formation gamma ray, DWOB, DTOR, MVC and APWD are optional • It has downlinking capabilities to change the bit rate, frequency, FSL and telemetry mode • There isn’t power supply for the up-extender in MTF 9.2.1. Components

MMA - M10 Modulator Assembly MEA - M10 Electronics Assembly MTA - M10 Turbine Assembly MDC - M10 Drill Collar MGR - M10 Gamma Ray MDI - M10 D&I MGD - M10 Gamma Ray Dummy MVC - M10 Vibration Chassis MTK_A - M10 Kit MSSX - Saver Subs

9.2.2. MMA Considerations • Rotor/Stator Gap • Zero gap = 0.08” • Oil Level • Reservoir → 360 cc • Oil leak → 0.5 cc • Status flag → 30 cc • Hours remaining → 60 hrs • Flow Configuration • 225 – 2000

Tatiana A. Silva

35


Dez - 2006

• LCM • < 50 ppb • well mixed • pumped w/ toll turned off • Failure • Open position → small drop in the standpipe pressure • Closed position → large increase in the standpipe pressure • Cold Start PPL/ BPSK/ 1Hz/ 0.5bps/ low temp/ jamming at pump up → restart the tool 9.2.3. MEA Sub Components • MEC - M10 Electronics Chassis • LTB → 24 V • ROP → 12 V • MDI - M10 Direction & Inclination Package • D&I is 7.71 ft / 2.35 m from ROP • MGR/D - M10 Gamma Ray/Dummy Package • MVC - M10 Vibration Chassis • MEH - M10 Electronic Housing 9.2.4. MGR – Gamma Ray • Sources of natural gamma ray: thorium, potassium, and uranium • The effect of the potassium (mud) on the MGR cannot be corrected • Plateau type scintillation detector GR→ NaI (thallium)→ light flash→ photocathode→ electron→ photomultiplier→ many electrons→ discriminator circuit • GRHV → at a certain range of high voltages the number of counts registered by the device does not change as the voltage increases (the readings plateau). A value in the middle of this range is then picked as the GRHV for the tool • Corrections: mud weight, collar size (tool size) and bit size • Real time sample rate → 11 sec • The PP averages the GR measurement every 30sec

Tatiana A. Silva

36


Dez - 2006

9.2.5. MTA Considerations • Oil Level • Reservoir → 850 cc • Oil leak → 1.5 cc • Status flag → 50 cc • Hours remaining → 33 hrs • Turbine configuration X flow range • 300 - 600 gpm (standard) • 400 - 800 gpm (standard) • 600 - 1200 gpm (standard) 9.2.6. MDC Considerations • • • •

Connection integrity (do not exceed the DLS limits) Connection torque ROP/IWOB port integrity Extender preparation (clean / dry / DC111) • Go / No Go • Resistance ~ MΩ • Fishing diagram 9.2.7. IWOB / MVC

Tatiana A. Silva

37


Dez - 2006

9.2.8. Some Specifications Collar Size Pressure Drop Const.*

6.75 16000

8.25 NF 16000 HF 29000

9 / 9.5 29000

* PDROP = GPM 2 × MW ( ppg ) C

9.2.9. PPL Jamming • • • • • • • •

Cycle pumps Rotate, if possible Work the drill string, if possible Vary flow rate Drill ahead for a while Reduce LCM content in mud Change shaker screens Pump the water pill (low-viscosity sweep basically)

Tatiana A. Silva

38


9.2.10.

Dez - 2006

IWOB Calibration

• IDEAL → MWD Init • DWOB • Tool 3 ft of the bottom • Pumping and rotating • Wait for the DWOB reading be stabilized • Zero DWOB → YES • DTOR • Stop rotating • Work the drillstring • Tool 3 ft of the bottom • Pumping • Wait for the DTOR reading be stabilized • Zero DTOR → YES 9.3. TeleScope Benefits: • Accurate well Placement • Large power generation capacity • 2 Mb memory Considerations: • IDEAL ≥ 10 • HSPM ≥ 10 • TSIM2 • Can support 80 dpoints • Clock battery must be replaced each 3 months Collar size DLS_rotating DLS_sliding Pressure (Kpsi) Pressure drop const

Tatiana A. Silva

675 4.5 15 25 16000

825 4 12 25 16000

29000

900 3.5 10 25 29000

39


Dez - 2006

9.4. Downlink PowerPulse SlimPulse

TeleScope

IMPulse

Legacy

Manual Fast

*

*

* IMPulse requires V8.1_B06 or higher software * PowerPulse requires V8.0_B93 or higher software

PowerPulse SlimPulse

TeleScope

IMPulse

Telemetry

Frequency

Baud Rate

FSL

Record Rate

*

*

Auto DLK Bit Time

VPWD Power

* Only using Manual Fast Downlink

Baud

PowerUP telemetry bit rate (bps): 1=0.5 | 2=0.75 | 3=1 | 4=1.5 | 5=2 | 6=3 | 7=6 | 8=12 | 9=16 Modfreq PowerUP modulator carrier frequency (Hz): 3=0.625 | 4=0.75 | 5=1 | 6=2 | 7=10.5 | 8=12 | 9=13.5 |10=16 | 11=21 | 12=24 Telemod PowerUP telemetry mode: 2=QPSK | 3=MSK

Tatiana A. Silva

40


Dez - 2006

9.4.1. Legacy • Minimum Drop for Downlink 500 Turbine RPM • Low Motor Inhibit Level: 1200 Turbine RPM after the tool is turned ON 1500 Turbine RPM before the tool is turned ON • High Motor Inhibit Level: 4300 to 4700 Turbine RPM (electronics controlled) • Downlink frame 12Hz, 1.5 bps, BPSK 9.4.2. Manual Fast • High state Flow near to your drilling flow rate ~ 500 GPM • Low state Flow of 10% less ~ 450 GPM • Stay in high state for a minimum of 15 seconds before sending a command

Tatiana A. Silva

41


Dez - 2006

10. LWD Tools Measurements: • Resistivity • Density • Porosity • Gamma ray • Annular pressure / temperature 10.1.

ARC • • • •

• • • • • •

• •

Tatiana A. Silva

Electromagnetic propagation tool Collar sizes 3 1/8”, 4 ¾”, 6 ¾”, 8 ¼” & 9” 5 transmitters and 2 receivers Transmitter spacing: Arc312/475: 10, 16, 22, 28, 34 in. Arc6/8/9: 16, 22, 28, 34, 40 in. Dual frequency: 2 MHz and 400 KHz (except older Arc475 tools) 52 MB memory with Motorola chips Annular Pressure While Drilling (APWD) (except Arc475 tools) – 20 Kpsi / 25 Kpsi AIM receiver antenna 30 restivities (2 MHz/ 400 KHz/ Blended) Resistivity Scan-rate: Old → min = 5 sec – used ≥ 6 sec W/MR06 → min = 2 sec – used ≥ 3 sec (MR06 – Low noise tools) Resistivity Record-rate = Scan-rate GR Update-rate = 28 sec

42


10.1.1.

Some specifications

Collar size DLS_rotating DLS_sliding Pressure (Kpsi) Pressure drop const 10.1.2. • • • • • • •

Dez - 2006

675 8 16 20/25 121000

825 7 14 16/25 970000

900 4 12 16/25 970000

Rt measurement

Locate hydrocarb. (w/ GR and density porosity) Estimate the volume of hidrocarb. Correlate logs Invasion determination Anisotropy determination Fracture determination Geosteering

Tatiana A. Silva

43


Dez - 2006

Measurements: • Attenuation → better depth of investigation Att = 20Log 

A1   dB  A2 

• Phase Shift → better vertical resolution PS = P2-P1

Phase

Rm Rmc Rxo

→ mud → mudcake → flushed zone

Tatiana A. Silva

Attenuation

Rt Rmf Rw

→ uninvaded zone → mud filtrate → formation water

44


Dez - 2006

Environment: • Resistors in parallel 1 Rmeasered

=

1 1 + Rxo Rt

• Ideal environment Rm > 10 Rt (resistive mud – OBM) Dielectric Constant: • Important at high resistivities ε=

108.5 εr + 5 Rt 0.35

Limitations due dielectric effects: Transmitter Spacing (inches) Resistivity in Ohm.m 16 22 28 34 40 Phase 0.2-200 0.2-200 0.2-200 0.2-200 0.2-200 Attenuation 0.2- 20 0.2- 30 0.2-50 0.2-50 0.2-50 Conductive formation: • More ions to absorb the energy of the wave • ↓ Depth of investigation • ↑ Vertical resolution Resistive formation: • ↑ Depth of investigation • ↓ Vertical resolution

Tatiana A. Silva

45


Dez - 2006

10.1.2.1. Depth of Investigation • • • • • •

It is defined as 50% of IRGF (integrated radial geom. factor) Deeper DOI → less mud effect Long space better than short space transmitters 400 KHz better than 2MHz Att better than PS Resistive better than conductive formation 10.1.2.2. Vertical resolution

• It is defined as the 50% point of the vertical response function • Higher vertical resolution → smaller formation beds / more accurately • Qualitative: the bed can be detected • Correlate logs • Must be corrected before formation evaluation • Quantitative: the toll read at least 90% of the Rt • Correlate logs • Formation evaluation • No transmitting space effect • 2 MHz better than 400 KHz • PS better than Att • Conductive better than resistive formation 10.1.2.3. 400Khz Advantages • • • •

Depth of investigation Less noise signal Less eccentricity effect More sensible to bad calibration 10.1.2.4. Borehole Compensation (rugosity) RT1 (16) RT2 (22) RT3 (28) RT4 (34) RT5 (40)

Tatiana A. Silva

→ → → → →

T1 T1 T2 T3 T3

T2 T2 T3 T4 T4

T3 T3 T4 T5 T5

46


Dez - 2006

10.1.2.5. Borehole Corrections • Bit size • Mud resistivity (at bottom hole temperature) 10.1.3.

Gamma Ray measurement

• Sources of natural gamma ray: thorium, potassium, and uranium • Real-time curves ARC_GR_UNC_RT [GAPI]: Calibrated GR ARC_GR_RT [GAPI]: Calibrated and environmentally corrected GR • Recorded-mode curves GR_ARC_RAW[CPS]: Uncalibrated GR_ARC_CAL[GAPI]: Calibrated GR_ARC_FILT [GAPI]: Calibrated and filtered (averaged) GR_ARC [GAPI]: Calibrated, filtered and environmentally corrected • GR GAIN factor: 0.8 – 1.2 Environmental Corrections: • • • • •

Bit size Tool size Mud weigh Potassium % Barite (ON/OFF)

Tatiana A. Silva

47


10.1.4.

Dez - 2006

ARC 6/7/8 Checklist

PRE-RUN 1) 2) 3) 4) 5) 6) 7) 8)

Visual inspection Check connections Torque in the sub Torque on the extender Go-no-go Resistance ROP voltages Fishing Diagram

BATTERIES 1) Check the jam nut o-ring 2) Grease 3) Depassivation • Resistors – 4 W / 100 Ohms • OCV → ≥ 21 V • LV → ≥ 19 V PROGRAMMING 1) Test communication 2) Edit job file 3) Load cal record a. Read from tool i. Max Temp = 150 ii. Max Pressure = 20 iii. GRHV and GR Gain → OST iv. No-APWD → POFF = 0 v. APWD 1. APRS ~ 14 psi 2. RPRS ~ 117 psi 3. POFF = RPRS – APRS b. D:\TOOLDATA\Run\ARC → ARC#SN#RUN.CAL 4) Edit configuration – Rates a. System → 5 b. Resis → 6 Tatiana A. Silva

48


Dez - 2006

i. System → you can put 60 ii. Raw_@2M → 6 iii. Raw_@400K → 6 iv. Res_Misc → you can put 60 v. Blend_Res → you can put 0 vi. Others → 0 c. Gamma → 6 i. Gamma → n x 6 ii. CGamma → 0 d. IAB i. No-APWD → 0 ii. APWD → 12 1. Pres_IAB → 12 2. Con_Pres → 12 3. IAB_Frame → 0 5) Edit configuration – Coefficients a. GammaRay → PGR_Rate GR_Rate =

3600 2(dp / ft ) × ROP ( ft / h)

b. DefFreqSel → 1 / 1 6) Edit job profile a. Add b. Forever c. Enter mem. size 7) Initialize the tool 8) F9 9) Status words → F7 10) Check calibration 11) Diagnostic → Recorded mem. → Summary 12) Diagnostic → Snapshot (STATE.DAT)

Tatiana A. Silva

49


TLSW ABAM ABBM ABAT ISBS ALTB ARVP ARVN TIMP SCNT ACCL DERR RESS AMC2 AMC4 GRHV PGRA PGRP GRAP APRS ATMP RPRS

Dez - 2006

Tool status word Batteries current (mA) Battery voltage Internal serial bus status error LTB voltage Power supply (V) Temperature Shock count Accelerometer voltage (shock) Data error on ISB bus Resistivity error from res sub-system Amplitude control @ 2 M: T5|T4|T3|T2|T1 Amplitude control @ 400 K: T5|T4|T3|T2|T1 GR high voltage GR_Raw (API) GR_Avarage (cps) GR_Avarage_Real_Time Annular pressure (w/offset) Annular temp. Annular pressure (w/out offset)

0 300 – 400 ~ 10 ≥ 18 V 0 0 10 ± 0.2 -10 ± 0.2 Amb. 0 10 0 0 77777 77777 OST ± 10

~ 14 psi Amb. ~ POFF + 14 psi

POST-RUN 1) Process → Process now 2) Utilities → ASCII Time Frame → Non wave form 3) Utilities → Tech Log ABAM / ABBM / TEMP / ABAT / ALTB / ARCSTAT / SHKLV 4) Check: a. STATE.DAT → compare pre and post run b. DUMP.DAT → elapsed PC time = elapsed tool time c. RESET.DAT → number of resets (must be empty)

Tatiana A. Silva

50


10.1.5.

Dez - 2006

Resistivity Interpretation

POLARIZATION HORN

BED BOUNDARIES

• High relative dip angles ( ≥ 50 deg) • High contrast in resistivity • Rps > Rad (spikes) • Long > Short ANISOTROPY

• Thin beds • Rps and Rad will cross • In the middle, Rps will spike • 2MHz is more sensible DIELECTRIC EFFECT

• High relative dip angles ( ≥ 60 deg) • Anisotropic formation • Rps > Rad • Long > Short RESISTIVE INVASION

CONDUCTIVE INVASION

• Sand • Usually OBM (Rmf > Rt) • Rps > Rad • Short > Long BAD CALIBRATION

• Sand • WBM (Rmf < Rt) • Rad > Rps • Long > Short ECCENTRICITY

• Curve separation in Rps (all log) • Long > Short FRACTURING • • • •

OBM Shale Rps > Rad Short > Long

Tatiana A. Silva

• Resistive formations • Rad > Rps • Short > Long

• • • • •

OBM Wet rock Big hole / small tool Only 2MHz is affected (spikes) Mitigation: blended resistivity

51


10.1.6.

Dez - 2006

APWD

The Annular Pressure While Drilling (APWD) measures the hydrostatic pressure of the mud column in the annular space and this value may be used to compute circulating and static mud densities Important Information:

Principal Functions: • Monitoring hole cleaning • Monitoring the pressure/fracture gradient w/ ECD • Kick/influx detection Some Concepts: • • • •

Pore pressure (fluid pressure) Fracture pressure (breakdown pressure) Hydrostatic pressure (column of drilling fluid pressure) Leak-off pressure (Maximum Allowable Annular Surface Pressure) o It is defined as the difference between fracture and hydrostatic pressures at the casing shoe • Differential pressure o Difference in pressure the hydrostatic head of the mud column and the formation pore pressure • Surge Viscous mud + BHA going in → mud is forced into the formation • Swab Viscous mud + BHA going out → formation fluid influx to the well

Tatiana A. Silva

52


Dez - 2006

Factors that affect APWD: • • • • • • • •

Mud weight Hole depth (true vertical depth) Cutting load in mud Mud temperature Mud viscosity and gel strength Drillstring speed and rotation rate Pump pressure Mud flow rate and flow regime (Laminar or turbulent flow)

D-points in the utility frame: • To provide ESD during connections o PMAX o PMIN o PESD • To provide a LOT or a FIT o PMAT o PMAX o PMIT o PMIN o ESDT o PESD

Tatiana A. Silva

53


Dez - 2006

EQUIVALENT STATIC DENSITY (ESD) • Pumps turned off ESD =

Annular _ Pr essure [g × (TVD − EHED )]

EQUIVALENT CIRCULATING DENSITY (ECD) • Pumps turned on • It is corrected for friction pressure losses in the annulus ECD =

Annular _ Pr essure + Annular _ Pr essure _ Loss [g × (TVD − EHED )]

Annular _ Pr essure _ Loss =

APL [g × (TVD − EHED )]

RETURN TO SEA FLOOR ESD =

ECD =

Tatiana A. Silva

(P

annulus

(P

annulus

− Psea _ water )

g × [TVD − (WD + Air _ gap )]

− Psea _ water )

g × [TVD − (WD + Air _ gap )]

+ Annular _ Pr essure _ Loss

54


Dez - 2006

ESD AND MEASUREMENT

Tatiana A. Silva

55


Dez - 2006

LEAK OFF TEST PTD = SPPA x Gain + Offset Gain =

PMAX − PESD SPPMAX − SPPSTATIC

Offset = PESD − (SPPSTATIC × Gain )

• FIT → Formation Integrity Test • LOT → Leak-off Test • ELOT → Extended Leak-off Test

Tatiana A. Silva

56


Dez - 2006

INTERPRETATION GUIDE

Tatiana A. Silva

57


Dez - 2006

11. Bibliography 1. ENG 1 Presentations; United Kingdom Training Centre, 2006 2. PowerPulse Operations Reference Manual; Barry Cross & Kuatrinnus Wijaya, 2004 3. TeleScope Operations Reference Manual; Kuatrinnus Wijaya, 2005 4. ARC 6/8/9 Uniform Operating Procedures; Schlumberger, 2000 5. APWD Self-Learning Package; Schlumberger, 2001 6. InTouch3866229 –Extended Leak Off Test procedures; Randy Green, 2006

Tatiana A. Silva

58

Schlumberger Engineer Guide (MWD/LWD)

Recommend Documents