WELL COMPLETION PROGRAM

The purpose of well completion is to provide communication between the reservoir and the surface production facilities.

TYPICAL WELL COMPLETION CONFIGURATION

Why well completion is so important ?To effectively drain out the reservoir fluids to surface. Proper completion design is crucial in maximizing recovery. To provide subsurface and surface flow control and safety. Several zones could be produced selectively or commingle it.

Isolate gas and water zones. To support wellbore and avoid excessive sand production.

The well completion provides :

Pressure controlA replaceable conduit for produced fluidsSelectivity of produced intervalsSimple well killing facilitiesPotential for the exclusion of solids

Well Completion Design Consideration2134567

1. Design Data RequirementWell Testing Data

Production rateProductivity Index, Skin and AOFBasic Sediment and WaterReservoir Pressure, PrBottom Hole Flowing Pressure, Pwf TemperatureGas Oil Ratio (GOR), Gas Lliquid Ratio (GLR) and Watercut (WC)Type of fluid (oil, gas or water)Degree APIViscosityDensityH2S, CO2 contentFluid composition

1. Design Data Requirement ( cont..)

Reservoir Rock Properties

DepthThicknessPorosity and PermeabilityCapillary pressureRock strength (Brinell Hardness Number and compressive strength)StressesYoung ModulusPoissons ratioFormation grain size (sieve analysis)

IPR with various Water Cut and GORsensitivity

10% WC40% WC> 60% WCIncreasing water cutPressure, PsiProduction Rate, QHigh GOR scf/stbGOR 400 scf/stbGOR 100 scf/stbIncreasing GORPressure, PsiProduction Rate, QIPCTPCNotes: IPR Inflow Performance Relationship; TPC Tubing Performance Curve; GOR- Gas Oil Ratio 2. Design Process Tubing Selection

IPR with THP and Pr SensitivityIncreasing THPTHP 500 psiTHP 100 psiTHP 200Pressure, PsiProduction Rate, QInitial PrDepleted PrPressure, PsiProduction Rate, QNote: Pr Reservoir Pressure

Completion Tubing Sizes

TUBING SIZE SENSITIVITY

Typical Casing Program

Completion Accessories

3. Special Study Requirement

PVT Core Analysis Metallurgy

Formation Water/Crude Analysis

Production rate /Inflow performane Formation strengthFluid type (corrosion, scale and wax/asphaltene)Reservoir permeabilityReservoir pressure No. of reservoirsReservoir management4. Reservoir Considerations

There are various types of well completion :5. Types of Well CompletionSingle string / selective singleDual stringGravelpackslim well monoborehorizontalmultilateraltwin well / triple wellY Block completionsmart / intelligent well

Selective ZoneSelective ZoneGravel PackedGravel PackedCased HoleWell Completion: Single String TypesWith and without gravel packedCased HoleCased HoleCased Hole

Well Completion Dual Strings TypesWith & Without Gravel PackedCased Hole No Gravel PackedShort String Selective/Non SelectiveCased Hole With All Gravel Packed/Only Shallower Reservoirs Gravel Packed

Slim WellDrilling small hole sizes and completing with smaller casing scheme.

This will enable faster drilling with less casing tubular, cement and associated drilling materials hence lower cost.

MonoboreBig bore Monobore(e.g. 3 1/2 tubing with 3 1/2 liner)4-7 tubular

DUAL SLIMHOLE MONOBORE

Horizontal Well

Twin well - HorizontalRequires special wellheadand x-mas tree arrangementTwo wells in one conductor

TAML (Technology Advancement MultiLateral)

EW-117Level 6 Multilateral

The Triple Wellhead is now a proven technology

It will make a marginal field economical to be developed

It has the potential also to enhance project economics with installation of smaller platforms to drill the same number of wellsTriple Well Head

Three wells drilled and completed from one shared conductor

It provides 6 production strings

Triple well

Y Block CompletionWithout Y Block, selectivity on short string is not possible (for gravelpack completion).Typical Dual string Completion

SMART2 SMART VALVES Under Balanced Drilling SMART Commingling Expandable Sand Screen Triple Gauge Interval Control Valve Lubricator Valve150 ftah (50 ft tvd)8 1/2 hole, TD at 8113 ft (3890 ftss, 69 deg)9 5/8 csg @ 7864 ftah (3630 ftss, 69 deg) 13 3/8 csg at 4000 ftah (2461 ftss, 69 deg)26 conductor @ 600 ftah7 Tbg L80 CS3 1/2 Tbg L80 CS3.1/2 SSD3.1/2 Ball Valvewith P/T gauges18 5/8 surface casing @ 1600 ftah (1445 ft.tvd, 37 deg)H1L1L2SSD

6. Methods of Well CompletionCased holeOpen hole

METHOD OF WELL COMPLETIONConventional Single/dual

Slimhole-monobore 2613-3/89-5/8724 / 20x 13-3/89-5/83-1/2 tbg2 x 72 x 3-1/2SlimholeSingle3-1/2726TD = 5450-8000 ft4-1/2

Sequence of Completion Operations :Well cleanoutPerforateKill well (Sand exclusion - if required)Run and set completion stringInstall X-mas treeFlowline Tie-in Unloading wellHandover to production

reservoirreservoirWell Preparation And Cleaning

reservoirreservoirWell Perforating

reservoirreservoirRunning Completion

Install Christmas Treewell

Production Flow Line Tie-InProduction headerToProduction systemwell

reservoirreservoirUnloading Well and Handover To Production Operations

SafetySimplicity/ReliabilityWell Surveillance/Monitoring Requirement Tubing Stress and MovementFuture Slick/E-line Intervention TechnologyFuture Work-over and Abandonment.7. Mechanical Considerations

There are different ways of completing wells with different types of artificial liftTypes of artificial lift :Gas lift Sucker rod (Bean Pump)Progressing Cavity Pump (PCP)Electrical Submersible Pump (ESP)Subsurface Hydraulic Jet Pump (SHJP)Plunger Lift

Artificial lift Gaslifting Well

Gaslift SystemSide Pocket Mandrel with Gas-Lift ValveArtificial Lift

Sucker rod (Bean Pump)Artificial Lift

Artificial LiftSucker Rod Pump (SRP)

Progressing Cavity Pump (PCP)Artificial Lift

Artificial LiftProgressive Cavity Pump (PCP)PCP Down Hole Equipment PCP Surface Facilities

Artificial LiftProgressive Cavity Pump (PCP)

Artificial LiftElectrical Submersible Pump (ESP)

Electrical Submersible Pump (ESP)Artificial Lift

Artificial LiftHydraulic Jet Pump (HJP)

Artificial Lift

Hydraulic Jet Pump (HJP)

Plunger LiftArtificial Lift

THANK YOU

PCSB's well completion reviewMost of PCSB's wells are cased hole either single or dual completion. However, there are a few wells completed opened hole (slotted liner).Tubing size used range from 2-3/8" to 5-1/2 OD.PCSB has completed horizontal wells, multilateral wells, wells with gravel packing completion, slim well and one twin well. Completion with 1 packer to 6 packers, completing from 1 to 5 zones in a single wellbore.

*The diagram showing a complete production system from reservoir to sales point. Well completion start from the sand face or wellbore up to the well head (in circle).This is a critical part of oil & gas production system, without this we cannot bring hydrocarbon to surface.*These are typical well completion commonly used in our operations.Mostly in our operations, single or dual string completion, conventional/deviated wellsSingle completion horizontal well and dual strings multi-lateral completion (level 6)

*Proper completion design is crucial in maximizing recovery and It is so important toProvide flow control through zones isolation i.e. SSD/packers/cement/casing, Choke, Christmas tree valves (master valve, choke valve, wing valve, crown valve, gaslift injection valve)Safety : Subsurface safety valve (SCSSV), surface shutdown valve, *The well completion also provides the following.*In designing well completion, these 7 elements must be considered thoroughly.

*These are data required for production technologist or well completion engineer to design well completion.*Reservoir data required for borehole stability study and to decide wellbore completion requirement i.e. sand screen, gravel-pack, frack & pack, etc.*Some example of tubing size sensitivity analysis to water cut and GOR.*And also sensitivity to reservoir pressure and tubing head pressure (back pressure).*These are various size of tubing production from the smallest 2.3/8 up to 5.1/2Some area or gas well uses casing as production tubular, i.e. 7 tp 95/8 *This is an example of tubing size sensitivity analysis using one of nodal analysis program (PCSB normally use EPS Wellflo to select optimum tubing used).To analyze at worse conditions i.e. high GOR or high water cut or low pressure, what is the optimum size to maximise production.

*This is normally the typical casing program after drilling and ready for cased hole production well completion.In case of open hole completion the production casing/liner will not be installed. However in case of hole stability become an issue slotted liner will be installed.

*Other special study required for tubing type or material selection, size of sand screen (if needed)*Reservoirs data and reservoir management strategy that need to be considered for well completion.*Various types of well completion based on requirement or problem of each well in order to maximize oil recovery or may be the most optimum selection that could be driven by production and cost.

*These are various types of single string completion, with and without gravel-packed*Why we need slim well? Is to reduce drilling cost.If only one reservoir/zone to complete.*Monobore well completion: Producing casing OD 7 9.5/8 with single string completion*This is dual well head with slim hole and monobore well completion.*This is a simple horizontal well - single string cased hole with liner completion*This completion requires twin wellhead or splitter wellhead in one conductor.

*These are multi-lateral from level 1 to level 6*This Level 6 multi-lateral completion installed in Erb West Field, Sabah Operation.*The worlds first tripple wellhead was installed in Bokor field, Sarawak Operations.Suitable for small offshore structure i.e. for jacket, tri-legged, light structure etc.*Each well completed in its own production casing with dual strings completion.Provides 6 producing strings in one single big conductor

*With Y Block completion, more zones could be produced through short string selectively for gravelpack completion*By installing down hole gauges and inflow control data pressure, temperature and flow down hole could be acquired and monitored.*This is another type of smart well completion to commingle production from 2 zones to avoid cross-flow.*Based on the data discussed, then we decide to go for open hole or cased hole completionSingle or dual strings completion naormally based on number of layers or producing zones.The requirement of SPM depend on fluid properties, reservoir pressure and production strategy *These are types of casing scheme for conventional, slim hole and monobore well completion*This is a list and sequence of completion operations*Any accessories required down hole must consider the following requirement.Safety: To flow the well in safety manner and follow production guidelines i.e. not to produce with high GOR -> leds to venting/flaring & RMP violation. Must have two barriers (SCSSV & AutoCon Valve) Simple & reliable: Easy to RIH & install casing/tubing/packers, Well surveillance: Wireline GL valve changes, BHP & BHT surveysTubing size selection to consider tubing stress, dented, bend, twisted during RIH or after installedSlick/E-line technology i.e. Caliper survey, downhole video/camera, thru TCP gun, logging, etc*This a list of artificial lift except gaslift, normally installed at the later stage of well life.*Gas produced with high-high pressure well injected into low pressure well annulus (behind tubing) to help lift-up liquid in the tubing.Normally most of our process platform, LP gas compressor used to recycle the injected gas which produced with liquid (water + crude) as LP gas, compressed to HHP gas for gaslift.

*The gas go into tubing through gaslift valves at the side pocket mandrel (SPM) mix with the liquid in the tubing, lighten the liquid column, reduce back pressure to allow reservoir pressure to push the liquid in the tubing up.*Sucker rod or bean pumping normally for onshore well.For high water cut well above 90% water cut.*Schematic of sucker rod pump surface and subsurface facilities.*PCP is a positive displacement pump. Drive head use to rotate rotor down hole.There a few types of drive head for PCP, normally installed onshore. Driven by electric motor or hydraulic power (drive by gas or diesel engine) Cheaper to use lorry and crane to install it on land.Recently it was re-design i.e. insert PCP to be able to install offshore using portable Hydraulic Workover unit (HWU)

*Schematic of PCP well : Surface & subsurface accessories (housing, elastomer & rotor)*It can be installed in both conventional and horizontal wells.Sucker rods use to connect drive head at surface to downhole assembly (rotor)*ESP motor, pump and BHA installed down hole attached to tubing. Electric cable attached behind the tubing from surface down to motor to sup[ly power.Require rig to retrieve tubing if motor malfunction and for service.*These a few type of ESP Assembly down hole. Conventional versus coiled tubing ESP assembly.CT-ESP could be retrieved using CTU. Using stinger and Polish Bore receptacle to connect with down hole parmenant packer.*Hydraulic jet pump is an alternative to gaslift system. Instead of inject gas SHJP uses formation water or mix with crude as a fluid lift to lift crude up to surface with high pressure jet.*In Malaysia Operations, it was installed in Tembungo field (PCSB Sabah Operations) and Siwa Field (PCSB Sarawak Operations) *Plunger lift is also a positive displacment pump. Using plunger travel up and down to lift crude up to surface. Using high gas to push up and down the plunger in the tubing.Never use in Malaysia risk plunger stuck in tubing.