Coil Tubing Intervention in MultiLateral Wells from a Semi-submersible

Transcription

1 Coil Tubing Intervention in MultiLateral Wells from a Semi-submersible Ragan Stonier (Lead CE, AusBU) 5 th March 2009

2 Agenda Overview Where, what, why??? Preparation Rig challenges, interfaces Engineering Intervention tools, modeling Execution Result, Lessons Learned NanHai VI Slide 2

3 Where is the Vincent field located? Slide 3

4 What s the Development look like? VINCENT OIL FIELD PHASED DEVELOPMENT WELLS WA-28-L VN-G1 18m Oil Column VN-G1PH V 1 V 3 GOC N OWC 1330m TVDSS 30m Oil Column VNB-H2-PH VNA-A2 Manifold B V 2 FPSO VNA-A2-L2 OUT 12.4m Oil Column Vincent-2 Manifold A Development Program PHASE 1A PHASE 1B PHASE 2 YEAR Scale 0 1km Slide 4

5 What s the Vincent Completion look like? Upper Completion Safety Valve Gauge Production Packer TriLateral Intermediate Completion Isolation Packer Isolation Valve ML Junction Template Connector Anchor Motherbore Lower Completion Isolation Valve Liner hanger 5.5 ICD Screens w/ Swell Packers Lateral Lower Completion PBR 5.5 ICD Screens w/ Swell Packers Slide 5

6 Why use Coil Tubing Intervention on Vincent? History: 6 BiLateral wells brought online at RFSU in September 2 wells underperforming, suspected due to mud type in completion Well 7 (TriLateral) was in progress with amended practices Coil Tubing was available as contingency to access the wells Why: Cleanout the ID and treat annulus of two underperforming BiLaterals Conduct MPLT to obtain lateral inflow profile Utilise coil to bring on well 7 underbalance (to avoid losses) When: Intervention conducted from December thru January 2009 (xmas/cyclone) Slide 6

7 What was the Problem (parallel study)? Formation Sand Mud in annulus Oil and gas Slide 7

8 What was the proposed Program / Sequence? Run Tree/EDP/LRP/Riser for B4 Open MFIV s on B4 underbalance Unlatch, kedge over B1 to B1 Motherbore clean out to FPSO with Tornado Motherbore treatment (Shut-in) Dummy Deflector drift Install Deflector to access Lateral Lateral clean out to FPSO with Tornado Lateral treatment (Shut-in) Lateral MPLT while flowing to FPSO Recover Deflector Unlatch, kedge over & repeat for B2 Slide 8

9 Preparation Key Rig Challenges Variable Deck Load (VDL) Left BOP on next well Crane capacity Coil rig up / Welding Fluid handling (Rig / FPSO) Limited Pits Extra boat Man riding Cement Unit Stimulation Riser/EDP/LRP running No fluids return to rig Environmental Cyclones / Sea state Wave rider buoy Stevshark anchors Coil rig up / Welding Slide 9

10 Preparation NanHai 6 Deck Plan Slide 10

11 Preparation Rig up INJECTOR HEAD 25 bbls Tote tanks Out let in sack room Cement / Injection Unit Annulus Circulation Manifold ACMCU c/v Cement Line Lo Torques 2`` 5k hose Moonpool CT-BOP Check Valve SPDV To Drain Rig Floor Stuffing Box Seal Ram Shear Ram Slip Ram Tube Ram SPKV SPSV SPWV SPMV SFT 3`` Coflex hose 2`` adjustable Choke V-1 Transfer Pump Vent Line V-2 80 bbls Surge Tank 45 psi Relief Valve 3`` 602 Hard Pipe ACMDV ACMNU ACMUR c/v ACMBD ACM Annulus Reeler EDP AIV LRP ACV ROV Operable UXOV PIV SSR MIV 2`` 1502 Hard Pipe coil bleed point ASV Subsea Tree PSV MIV PWV Choke 50% Open FPSO XOV P/T Sensor AMV P/T Sensors PMV Flow line Connector PIV 01 ROV Operable DCB DCA Production Packer Flowbase DRIMS TRSV # CT in ML Wells Mar-2009 Production Line Slide 11 Intervention Line

12 Preparation ICON Skid / Jack system Slide 12

13 Preparation BJ Coil Tubing Welding Slide 13

14 Preparation BJ Coil Tubing Slide 14

15 Preparation BJ Coil Tubing Slide 15

16 Preparation Pipe Deck Slide 16

17 Preparation Subsea Tree / EDP / LRP Slide 17

18 Engineering Key Intervention Challenges Lateral access, Deflector Junction / Packer access Sand plugging & Clean out Stimulation (ICD) / Leak off MPLT damage Contingency (Fishing/Tomahawk) Reaching target (ERD, friction) Assumptions: Estimated 10% solids Estimated 0.24 Fc Max reach ~3900m (90+%) Max circ 4500psi Limit tool dp to 1500psi Max 3.5bpm rate Coil weld vs Connector Depth correlation Pump capability Production impact (Flowlines) Techniques: Bullhead squeeze (Rig/CT) Swab cups / Inflate packers Slide 18

19 Engineering Modeling Friction of the Coil RIH Result Comparison in B1 MB Estimated Depth Reached (mdrt) 3000 Surface Weight (Lbs) is TD 4350 is TD is TD Depth (mdrt) 19 B1 B2 Slide 19

20 Engineering Modeling Injection into ICD s 3 bpm NetTool was inadequate in modeling skin and pipe friction with CT in hole 1.5 bpm Rate in the C.T back side = 0 as all the rate goes into the lateral Rate profile in the M.B at different skin/ pressure drop across the perforations 1.5 bpm Rate in the C.T back side Perforated Liner 1950 psi R.P Y bpm 3 bpm X bpm Slide 20

21 Engineering Model of Stimulation Sequence CoilCADE* Wellbore Simulator - Formation Pressure History Flowing BHP with WHP of psi and keep max circulating at 4500 psi Shut in, RIH to max depth, pump 2 bpm diesel 15 m/min Formation Top Press Formation Bottom Press Pressure Below CT Liquid Interface(s) CT Depth Liquid Interface(s) 5000 Pressure - psi Displace with CT to Diesel (With SafeSurf) While RIH Coiled Tubing Measured Depth - m Toe Heel RIH Pump 0.5 bpm, Pull test 20 m each 300 m, Pump 3 bpm each 300 m penetration Base Oil +/ bbls POOH to the heel Displace CT to Diesel Treatment Time - min Shut in, POOH to the heel, pump 3 bpm, 80:20 mix 10 m/min Diesel +/ bbls 1000 Still Shut in, POOH to surface 0 Surface Slide 21 *Mark of Schlumberger

22 Engineering Actual Sequence (~4000bbls) Slide 22

23 Engineering Intervention Tool Strings Nozzle Tornado 5 GS Slide 23

24 Engineering Tornado Tool (cleanout / treat) Slide 24

25 Engineering ML Junction Intervention Tools Deflector Isolator Slide 25

26 Engineering MPLT Tools & Strategy Tool Damage on the ArrowDrill PKR Configure MPLT bullnose to stand up off casing Tool Damage on ML Junction Log only Lateral once Deflector in place Deflector LIH affects production Porting of 1 in deflector Deflector releases with 12klbs A Slide 26

27 Engineering Lateral Access (Contingency) 1. FIV Ball Valve Isolation / no-go 2. Agitator Increase reach in lateral 3. Inflatable Centraliser lifting fishing tools 4. Tomahawk / Tornado Lateral access Slide 27

28 Engineering Downhole CT Tool Strings Slide 28

29 Execution What did we actually do? Planned Sequence: Latch EDP/LRP/Riser to B1 Motherbore clean out & treat Dummy Deflector/Drift Set Deflector Lateral clean out & treat Lateral MPLT Recover Deflector Unlatch, Kedge over B2 Repeat sequence for B2 *** MPLT on TriLateral B4 Actual Sequence: Latch EDP/LRP/Riser to B1 Motherbore clean out & treat Cyclone Billy, jacked CT clear Unlatch, Kedge over B2 Motherbore clean out & treat Ran Agitator to target depth Close MFIV & Run Tomahawk Lateral clean out and treat Open MFIV Motherbore MPLT on B2 Repeat sequence for B1 Slide 29

30 What s the Vincent Completion look like? Upper Completion Safety Valve Gauge Production Packer TriLateral Intermediate Completion Isolation Packer Isolation Valve ML Junction Template Connector Anchor Motherbore Lower Completion Isolation Valve Liner hanger 5.5 ICD Screens w/ Swell Packers Lateral Lower Completion PBR 5.5 ICD Screens w/ Swell Packers Slide 30

31 Execution What did we achieve (result)? 1. Brought on 7 th well underbalance in solids free with good PI 2. Verified inflow from the logged well bore length 3. Proved up coil tubing re-entry into MultiLaterals (on a semi) 1 st 10-3/4 RapidX intervention 1 st Tornado/Tomahawk intervention 4. Obtained limited rate and PI improvement from damaged wells 5. Confirmed viable downhole tool choices 6. Achieved predicted reach into horizontal section 7. Implemented a CT skidding system (leak/cyclone) 8. No spill with ~10,000bbls base oil / diesel to FPSO 9. On budget within 4% of AFE Slide 31

32 Execution What did we learn? 1. Arrowdrill packer replacement required 2. Safety hazard engineering can be improved (1 x TRCF) 3. HUD is improved by the Agitator 4. Deflector is not robust with current geometry 5. Tomahawk is a good solution with the MFIV as no-go 6. Limited ability to treat annulus of ICD/screen 7. Varied MPLT tools on the market, look around 8. On the limit with CT kit (30days, 23runs, pin hole, spooler?) Slide 32

33 My personal take on this effort It s not rocket science, but... Time frame very very short Variety of technical hurdles Strong team ethic from day one Quality vendor support Maintained flexibility Demonstrated capability Achieved the unachievable...the ride was second to none! Slide 33