Packers and Liner Hangers - George E King Petroleum Engineering
Transcription
Packers and Liner Hangers - George E King Petroleum Engineering
Packers and Liner Hangers • Basic Overview • Applications and Selections of Packers • Setting Criteria and procedures What is a Packer? • A packer is a tool used to form an annular seal between two concentric strings of pipe or between the pipe and the wall of the open hole. • A packer is usually set just above the producing zone to isolate the producing interval from the casing annulus or from producing zones elsewhere in the wellbore. • Separates fluid types (or ownership), protects against pressures and corrosion. Why are packers used? • Tubing and packer used to isolate zone of interest - can be removed for repair. • Packers act as downhole valve for press control. • Packer can be a temporary plug to seal off the zone while work is done up the hole. • Subsurface safety valves used with packers for downhole shut-in. • Focus flow • Isolate between zones Packer Cutaway Drawing As the packer sets, the inner mandrel moves up, driving the cone underneath the slips, pushing them into the casing wall. The sealing element is compressed & extruded to the casing wall. Lock Ring and Mandrel Slips Cone Seal Inner Mandrel Ability to effectively set a packer depends on having a clean, non corroded set point and reaching the set point without fouling the slips or failing other components. Packers and Liner Hangers Mechanical isolation methods Two examples: 1. An external casing packer (ECP) set to seal the annulus between the surface or protection string and the inner, production string 2. A conventional packer set near the end of the tubing, that isolates the inner annulus from the tubing. Packer Considerations • Force on an area Remember, it’s a force balance. Area down = casing ID - tube OD Area up = tube x-section + casing ID - tube OD Packer Types & Selection Production Packers Retrievable Permanent Wireline Set Sealbore Hydraulic Set Hydraulic Set Hydrostatic Set Single Differential Set Dual Wireline Set Hydraulic Mechanical Single Grip Double Grip Multiport RMC Mech. Slips Hyd. Slips ESP Schlumberger Specific Packer Examples • Packer Examples – – – – Retrievables Seal bores Inflatables Wash Tools Retrievable Packers • • • • Expected to be retrieved More prone to leaks Need an equalizing port Release mechanism must be possible with well design Retrievable Packers Tension Set - Economical packer used in production, injection, zone isolation applications • Compact • Simple J slot control for set and release • Shear ring secondary release • Right-hand safety joint emergency release • Rocker type slips • Can be set shallow Weatherford Retrievable Production Packers Mechanical - Used in production, injection, fracturing, zone isolation and remedial applicatuions • Rotation set and release • Can be set with tension or compression • Tubing can be landed in tension, compression or neutral • Models rated up to 10,000 psi • Pressure equalization needed prior to upper slip release • Secondary shear release required Weatherford Retrievable Production Packers Mechanical Used in production, stimulation and testing • Compression set • RH rotation required to set, (LH option usually available) • Available with or without Hydraulic hold down buttons for differential pressure from below • By-pass needed for equalization of pressure, and for running and retrieval without surging/swabbing the well. Weatherford Retrievable Packers Wireline set - Used in production, injection, fracturing, zone isolation and remedial applications where wireline setting is preferred • • • • • • • • • Weatherford Can act as a bridge plug prior to production Connect to tubing via On/Off Tool with blanking plug Tubing can be landed in tension, compression or neutral Slips above and below the elements Triple element pack off system Pressures to 10,000 psi Fluid bypass needed for pressure equalization Retrieved on tubing Secondary shear release needed Seal Bore Packers • Allow tubing movement; however: – Too much contraction can pull seals out of PBR – Seals can “bond” to the seal bore over long time at higher temperatures – Debris on top of packer can stick assembly Unprotected seals below the packer may allow seal swelling by gas and fluids, causing seals to roll off if the stinger is pulled out. Deep Completions • Most typical is permanent packer with a PBR (arrangement depends on personal preferences, individual well configurations and intended operations). • Seal assembly length dependent not only on normal operations, but also fracturing, kill and expected workovers. Seal Bore Packers • High pressure & temperature ratings available • Multiple packing elements available • Short units are desirable for use in tight doglegs (>5o) and high (>8o/100ft) departure angles • Ability to set on wireline or with a hydraulic setting tool • Rotationally locked units needed for mill-ability • Share Seal Assemblies with permanent seal bore packers • Critical metallurgical and seals (O-rings, etc) should be isolated from wellbore fluids by main elements. Weatherford Retrievable Seal Bore Packer One-trip applications • Hydraulic set version retrievable seal bore packer available for one-trip installations • Seal assembly is run in place for one trip installation • Available with large upper seal bore to maximize ID • Rotationally locked components Weatherford Permanent Seal Bore Packers Used in one trip production applications • Seals run in place for one trip setting • A metal back-up system can be specified to casing ID to prevent element extrusion • Elastomer and materials available for hostile environments Weatherford Packer Considerations • Select seals for full range of expected temperatures, pressures, and fluids. • A back-up system is need around the main seal to prevent seal extrusion at high temps and pressure. • Examine slip design to help avoid premature setting during movement through viscous fluids, doglegs and rough treatment Seal Bore Packers Nitrile Seal or Viton Seal Steel spacer MOLDED SEAL SINGLE UNIT Molded Seals: • Recommended in medium pressure applications where seal movement out of the seal bore is anticipated. Chevron Seals: Used for higher pressure and temperature applications. CHEVRON SEAL SINGLE UNIT Weatherford End spacer Seal spacer Middle spacer Nitrile Seal or Viton Seal Seal Bore Packer Accessories • Tubing Anchor and Locator Assemblies • Seal Units and Spacer Tubes • Seal Bore and Mill-Out Extensions • Packer Couplings and Bottoms • Pump-out, Screw-out, and Knock-out Bottoms Weatherford Inflatable Packers and Plugs • Reasons to run and inflatable. – – – – – Need to set beneath a restriction. Need to set in open hole. In non-standard casing. Setting in multiple sizes of pipe on same run. Where larger run-in and retrieval clearances are needed. – Large diameter applications. Inflatable Setting Considerations The inflatable packer offers a way to set a seal in a larger area below a restriction. Holding ability of the inflatable is always suspect since it does not have conventional slips. The quality of the seal depends on how much the packer must expand over initial diameter, the length of the slide (placement run), the differential pressure it must hold, what fluid is used for inflation and the conditions in the area in which it is set. When deflating an inflatable packer, allow time (1 hr?) for relaxation of the elements. The elements never shrink back to initial diameter – allow about 30% increase in diameter for retrieval. Inflatables rely on expansion of an inner rubber bag that pushes steel cables or slats against the wall of the pipe or the open hole. The only gripping ability is generated by the friction of the steel against the pipe or open hole. This is critically dependent on the inflation pressure and the exterior slat or cable design. For a permanent seal, place several bailers of cement on top of the inflatable. Baker Perforation Wash Tool Used for selective acidizing of perforated intervals • Heavy Duty reinforced casing cups • Spacing between cups adjustable from 12” to any length by addition of standard tubing pup joints • Large internal bypass • Cup wear from casing burrs can be significant and may reduce seal, especially in long zones. Weatherford • The number of successful resets depends on casing conditions, pressures, slide length (running), temperature and deviation. Successful resets run from about 5 to over 20. Packer Seals Packer Slips Lawrence Ramnath - Trinidad A hydraulic set packer. Note the lower slips set by movement of the mandrel and upper slips set by piston action. Slips – Liner hanger J-Slot on a liner hanger. Packer Comparisons - from Weatherford Packer Type Weatherford Completion Systems (Bold Items are Preferred Products) HES Halliburton Solid head, Tension Set, Mechanical, Single Grip Compression Set, Mechanical, Single Grip PAD-1, PADL-1 Compression Set, Double Grip Packer Neutral Set, Double Grip Packer Schlumberger (Camco) Baker Guiberson AD-1 AL R-3 Single Grip Model G RB R-4 PR-3 R-3 Double Grip Hydraulic Set Retrievable QDG, QDH, Arrowset I-X (&10K), UltraLok, Double Grip HRP, Hydrow-I, PFH Dual Hydraulic Set Retrievable Hydrow IIA Wireline Set Permanent Arrowdrill B Lockset, Max J-Lok, MS FH, FHL, FHS Hydra-Pak HS, HS-S A-5 T-2 GT Model D F-1 MHS MH-2 WPL Perma-Lach RH PHL AHR RDH BHD Wireline Set Permanent Double Bore Hydraulic Set Permanent Arrowdrill DB Arrowdrill BH DA, DAB FA, FAB SB-3 Hydraulic Set Permanent Double Bore Retrievable Seal Bore Arrowdrill DBH SAB-3 MHR Arrow-Pak VTL (Versa-Trieve) Hydraulic Set Retrievable Seal Bore HPHT Hydraulic Set Retrievable Hydrow-Pak Retrieva-D, DB WS, WSB SC-1, SC-2 SC-2PAH G-1, GT-1 H-1, HT-1 PG PH PG-1 PH-1 G-10 VHR (Versa-Trieve) RSB Compression Set Service Packer CST, C5, H/D, MSG HP-1AH, SC-2PAH HP/HT EA Retrievamatic HPHT (Versa-Trieve Retrievable) RTTS Champ III, IV Compression Set Storm Packer Tension Set Service Packer CSTH, DLT 32A, Fullbore Tension C Fullbore BV Tension Packer Tubing Set Retrievable Bridge Plug Wireline Set Retrievable Bridge Plugs Permanent Bridge Plugs/Cement Retainer QDH w/ EQV, TSU G Lock-Set 3L RBP-VI P-1 Mercury N, K-1 EZSV, EZ Drill EZ Drill SVB Fas-Drill, HCS Type A Quik-Drill PR-3 Single Grip Hydrow-Pak R-4 AWB BWB AWS AWR MHR Uni-Packer I Uni-Packer IV Uni-Packer II G-4 Uni-Packer V SA-3 T Series SR-2 U-3 CA-3, C Series SR-1 Uni-Packer VI G-6, G-16 Uni-Packer VII G-77 RHS Uni-XXVII RHD SOT-1 KH Hydro-5 HRP G, GT H, HT Model S HDCH-V Hydro-10 HSD Model HS Model HSB M Omegatrieve Quantum Omegamatic R-104 WRP, CE, CE2 PCR, Plugwell, PBP Packer specifics from Baker Casing Design Options – think about running and setting packers. Mixed weights, same grade Small diameters at the top of the well may prevent entry by some packers. Mixed grades and weights Monobore: mixed grades, same weight Production Packers • Purposes – – – – Casing protection from fluids or pressures Separation of zones Subsurface pressure and fluid control Artificial lift support equipment Packer Considerations • Seal stability – pressure, temperature, fluid reaction • Force balance and direction – slip direction • resists upward motion, downward or both ways) • tension, compression, mechanical or hydraulic set Allowing Tubular Movement • Usually incorporate a PBR - polished bore receptacle, for a “stinger” or seal assembly to slide through. • Shoulder out on the PBR - if it can move, it will eventually leak. • Seals must match operating extremes as well as general conditions. Seal Bore Packer to Tubing Connections Seal Bore Extensions (SBE) Polished Bore Receptacle (PBR) Tubing Sealbore Receptacle (TSR) Seal Assembly Locator Types Locator Anchor Latch Snap Latch A “stinger” or seal assembly that is run on the end of tubing and “stings” into the polished bore receptacle (PBR) of the packer. Stinger Seal Materials • Single or mixture of elastomers • seal design variance • seals usually protect the slips from corrosive fluids. Tubing Seal Stability Seal Material Butyl Rubber Flurocarbon Nitrile Fluro-silicone oil 4 1 1 2 brine 1 1 1 1 H2S 1 4 4 3 CO2 2 2 1 2 1=good, 2=fair, 3=doubtful, 4= unsatisfactory Much larger data base available online. Halliburton Energy Services General Guidelines For Seals PEEK(2), (4) Compound Ryton(2), (4) Fluorel(3) Filled Aflas(3) Unfilled Chemraz(3) Unfilled 350 (177) 350 (177) 450 (232) 350 (177) 15,000 (103) 10,000 (68.9) 15,000 (103) Service °F (°C) (2), (4) Pressure psi (MPa) Viton(3) Filled Unfilled (1) Neoprene(3) Filled Nitrile(3) Filled Kalrez(3) Filled Teflon(3) Filled Unfilled 325 (163) 300 (149) 275 (135) 450 (232) 400 (204) 325 (163) Above 5000 (34.4) Below 5000 (34.4) 5000 (34.4) 3000 (20.7) 15,000 (103) 15,000 (103) 5000 (34.4) Environments H2S A A A A A B B NR NR A A A CO2 A A B B A B B C A A A A CH4 (Methane) A A A A A A A B B A A A (Sweet Crude) A A A A A A A A A A A Xylene A A A C A A A NR NR A A A Alcohols A A C B A C C B A A A A Zinc Bromide A A A A A A A NR NR A A A Inhibitors A A NR A A NR NR NR B A A A Salt Water A A A A A A A C A B A A Steam A A NR A A NR NR NR NR NR B B Diesel A A A NR A A A B B A A A Hydrocarbons A-Satisfactory NOTE: (1) B - Little or no effect C - Swells D - Attacks B C NR - Not recommended NT - Not tested This information provides general guidelines for the selection of seal materials and is provided for informational purposes only. Seal Specialists with Halliburton Energy Services should be consulted for the actual selection of seals for use in specific applications. Halliburton Energy Services will not be liable for any damage resulting from the use of this information without consultation with Halliburton Seal Specialists. (2) Contact Technical Services at Halliburton Energy Services - Dallas for service temperature and pressure. (3) Back-Up Rings must be used. (4) There could be a slight variation in both temperature and pressure rating depending on specific equipment and seal designs. Halliburton Energy Services General Guidelines For V-Packing (1) Halliburton Energy Services General Guidelines For V-Packing (1) (1) Packer Element Selection Chart N START STEAM/THERMAL APPLICATION W/NO HYDROCARBON FLUIDS Y N Y PERMANENT PACKER DESIGN N N PACKER IN OIL BASE MUD OVER 24 HOURS BEFORE SET? Y PACKER IN BROMIDE N Y TEMP 40°F TO 325°F COMPLETION FLUIDS MORE THAN 36 HOURS BEFORE SET? Y NITRILE ELEMENTS W/STANDARD METAL BACKUPS N Y TEMP 40°F TO 400°F NITRILE ELEMENTS W/TEFLON AND METAL BACKUPS N Y TEMP 100°F TO 400°F AFLAS ELEMENTS W/STANDARD METAL BACKUPS N Y TEMP 100°F TO 450°F AFLAS ELEMENTS W/TEFLON AND GRAFOIL WIREMESH AND METAL BACKUPS N TEMP GREATER THAN 450°F Y N TEMP 40°F TO 275°F PACKER EXPOSED TO BROMIDES? RETRIEVABLE PACKER DESIGN CHECK WITH YOUR HALLIBURTON REPRESENTIVE FOR SPECIAL APPLICATIONS NITRILE ELEMENTS W/BONDED GARTER SPRINGS N Y Y PACKER ELEMENTS EXPOSED TO AMINE CORROSION INHIBITORS? N Y TEMP 40°F TO 400°F FLUOREL ELEMENTS W/BONDED GARTER SPRINGS N Y N TEMP 100°F TO 400°F AFLAS ELEMENTS W/BONDED GARTER SPRINGS TEMP GREATER THAN 400°F CHECK WITH YOUR HALLIBURTON REPRESENTIVE FOR SPECIAL APPLICATIONS Y NOTE: (1) This information provides general guidelines for the selection of seal materials and is provided for informational purposes only. Seal Specialists with Halliburton Energy Services should be consulted for the actual selection of seals for use in specific applications. Halliburton Energy Services will not be liable for any damage resulting from the use of this information without consultation with Halliburton Seal Specialists. TEMP LESS THAN 550°F EPDM ELEMENTS WITH BACKUPS TEMP GREATER THAN 550°F CHECK WITH YOUR HALLIBURTON REPRESENTIVE FOR SPECIAL APPLICATIONS N Forces and Length Changes • Temperature: • Piston Effect: • Ballooning • Buckling: A tubing movement calculator is the best method, but the difficulty is in knowing accurate temperature changes and pressure changes. Is it Force or Length Change? • No packer - tube suspended and not touching well bottom - length change • Tube landed on packer - incr. force with increasing temp, shortening possible with cooling after downward force absorbed. • Latched tubing - no movement, only forces • Tube stung through - length changes unless locator is shouldered • If tube set in tension or compression, effects of temp depends on initial force and DT Temperature, length change DL = CLDT Where: DL = length change C = expansion coeff. for steel = 6.9x10-6/oF L = length of tubing DT = average temp change, oF Temperature, Force change • F = 207 DTa As • Where: F = temperature induced force DTa = change in average temp of tubing, oF As = cross sectional area of tubing What Temperature is Average? • If no circulation - assume all tubing is same as injected fluid temperature. (worst case) • If circulation is allowed, all but top few joints will be unaffected by injected fluid temp. - no temp change. (v. slight effect) • Injected fluid temp? - source dependent! • In dual packer - treat each packer as a separate calculation. Bottom string first. Temperatures in the Well? Circulating or High Rate Injection? 30 40 50 60 70 80 90 100 110 120 130 0 30 40 50 60 70 80 90 100 110 Tubing 130 Undisturbed Tbg Fluid 2000 Tbg Fluid 2000 Casing 1 Tubing Undisturbed Casing 1 4000 4000 6000 6000 8000 8000 10000 10000 BHST= 122*F 12000 BHST= 125*F 12000 14000 14000 BHTT= 86*F BHCT= 98*F 16000 16000 Frac job pump rate = 35-BPM Circulation pump rate = 8-BPM 18000 120 0 18000 Problem • Temperature Effect Only – Is a 6 ft seal assembly (effective seal length) enough to keep the tubing from unseating when the average temperature falls from 210oF to 100oF during a Frac job? L = 8000 ft. – Assume locator is shouldered but no downward force is applied. Problem • Temperature Effect Only DL = 6.9 x 10-6 x 8000 x 110 DL = 6.1 ft unseats! What if 15,000 lb downward force were applied to the tubing before the temperature change? How much temperature increase is spent lifting the 15,000 lb? • F = 207 x DT2 x 2.59 in2 DT2 = 15000 / (207 x 2.59) = 28oF Then: 110 - 28 = 82oF DL = 6.9 x 10-6 x 8000 x 82 = 4.52 ft What about those other factors? • Buckling, Piston, Ballooning - Use a computer program - better yet, use a couple of them (different assumptions). Temperature Extremes • The extremes of temperature change (higher than normal) are usually seen in operations involving cyclic thermal processes. • Lower than normal temperatures may be seen in permafrost, sea floor penetrating and CO2 operations. Setting the Packer • Chances of setting packers go up sharply when a casing scraper is run. (Remember the burrs on the perforations?) • The quantity of debris turned loose from the casing wall is often severe! (Tens of pounds worth!) Watch the formation damage. Packer Set Point Requirements • • • • • • Avoid setting packer in the same joint where previous packers have been set. Avoid doglegs, fault locations or high earth stress zones Adequate cement and bond required behind pipe at packer set point Caliper casing above and through the packer set point Clearance between packer and casing at set point is within rated range of packer Avoid zones of high corrosion, either internal or external. • • • • • • Remove burrs from pipe above packer set point Remove debris (dope, mill scale, mud, cement, etc.) on casing wall (fills slip teeth) Well pressures are within range of packer at set point Pipe alloy compatible with setting slips (hardness of casing relative to packer slips) Slip design & contact area acceptable for slip holding Weight applied to packer can be transferred to formation Information Required Before Setting Packer or Plug • • • • Wellbore drawing with all diameters Last TD tag – rerun? Doglegs and deviations Viscosity of fluid in wellbore – Calculate running speed vs. surge/swab. • • • • Copy of reference logs Where have other packers been set (avoid that joint) Set point requirements How can it be equalized if it has to be pulled? Job Checks • Measurements from CCL to a packer reference point. • Run in hole at about 100 fpm, slowing at ID restrictions. • Using CCL/GR, log up and correlate depths • Set packer – look for line weight reduction • Disconnect and log up a few collars (may be slightly off depth after disconnecting). Job Checks • Drop back and gently tag packer with setting tool to confirm depth. • Log back up a few collars. Packer Setting Guidelines • Drift • Scraping • Casing Support Drift the Casing • Casing ID requirements above the set point • Casing ID requirements below the set point • Check the drift to deepest point with drift of diameter and length of packer. Clean/Scrape The Casing? • Removal of perforation burrs minimizes elastomer seal damage • Removal of cement, mud, pipe dope and mill scale minimize debris that can fill the slips. • Scraping casing can increase packer setting success • Scraping casing can also produce some severe formation damage if perforations are not protected. Casing Scraper – Designed to knock off perforation burrs, lips in tubing pins, cement and mud sheaths, scale, etc. It cleans the pipe before setting a packer or plug. The debris it turns loose from the pipe may damage the formation unless the pay is protected by a LCM or plug. One very detrimental action was running a scraper prior to packer setting. The scraping and surging drives debris into unprotected perfs. Effect of Scraping or Milling Adjacent to Open Perforations 20 % Change in PI 10 Perfs not protected by LCM prior to scraping 0 -10 1 Perfs protected by 2 LCM -20 -30 -40 Short Term PI Change Long Term PI Change -50 -60 SPE 26042 Typical Completions • Single and Dual Zone Completion Types Single Zone Completion (Mechanical Packer) Packer isolates casing from production • Provides means of well control • Protects casing above packer from corrosion • Anchors tubing string On-Off Sealing Connector Retrievable Packer Weatherford • • • • Tension Set Compression set Wireline Set Large Variety of accessories available Single Zone Completion (Hydraulic Set Packer) • Permits Packer setting without tubing manipulation –Common in offshore applications where SCSSV control lines prevent tubing rotation Flow Coupling • Allows one-trip installation Flow Coupling • With sliding sleeve, allows packer fluid changeHydrostatic Retrievable Packer out after wellhead is flanged (sliding sleeve not recommended in every case). Flow Coupling Seating Nipple • Requires tubing plugging device to set packer Spacer Tube Sliding Sleeve Ball Activated Pressure Sub Perforated Spacer Tube No-Go Seating Nipple Wireline Re-Entry Guide Weatherford –Wireline plug - preferred –Drop Ball Seat – debris problem? Single Zone Completion (Seal Bore Packers) Annulus Activated, Block and Kill Valve Sliding Sleeve Seal Bore Packer Mill-Out Extension Crossover Sub Flow Coupling Seating Nipple Spacer Tube Flow Coupling No-Go Seating Nipple Perforated Spacer Tube Crossover Sub Seating Nipple Wireline Re-Entry Guide Weatherford • • • • • Dependable Low failure frequency Generally permit larger flow ID’s Available as Permanent or Retrievable Production string may be anchored or floating, depending on tubing movement requirements (anchored or shouldered is highly recommended) • Packer may be plugged, can be used as temporary or permanent bridge plug • Permanent packers removed by milling operations • Retrievable Seal Bore Packers are removed in separate trip with retrieval tool – provided seals will release. Single Zone Completion (Seal Bore Packers w/Locator Seal Assy.) Sliding Sleeve Flow Coupling Locator Seal Assembly Seal Bore Packer Seal Spacer Tube Seal Bore Extension Tubing Seal Nipples Production Tube Spacer Tube Flow Coupling Seating Nipple Perforated Spacer Tube No-Go Seating Nipple Weatherford • Locator unit atop Seal Bore Extension allows tubing movement from press and temp changes: – Frac or Acid Stimulation – Production extremes and shut-in • Seals available to match environment: – Temperature Range – Pressure Conditions – Fluid Environment • Works well with tubing conveyed perforating (TCP) Single Zone Completion (Polished Bore Receptacle (PBR)) Locator Seal Assembly • Seal Bore Packer with large upper bore permits maximum flow area. • PBR above packer accommodates tubing trip/movement Retrievable Packer Bore Receptacle Anchor Tubing Seal Nipple Hydraulic Set Seal Bore Packer Mill-Out Extension Crossover Sub Shear-Out Ball Seat Sub Weatherford – Shear release locator allows one-trip installation with Hydraulic set packer – Large ID suitable for Thru-Tubing perforating Single Zone Completion (Stacked Selective Completion) Flow Coupling Sliding Sleeve Seal Bore Packer Seal Bore Extension • Permanent packers are stacked for multiple zone completion Tubing Seal Nipples – Zones are selective flowed or shut-in by sliding sleeves or ported profiles and plugs Flow Coupling Seating Nipple – Tubing may be anchored or floating Blast Joint Polished Nipple – Blast joints are placed across production interval to reduce flow-cutting of production lines Flow Coupling Sliding Sleeve Seal Bore Packer Seal Bore Extension Seal Spacer Tube Tubing Seal Nipples Spacer Tube • This type of completion design often has severe problems with leaking sleeves and corroded/eroded tubing in the straddled zone. No-Go Seating Nipple Production Tube Weatherford Single Zone Completion (Standard Dual Completion) Flow Couplings Seating Nipples Flow Couplings Flow Coupling Sliding Sleeve Short String Seal Nipple Dual Hydraulic Retrievable Packer Flow Coupling Seating Nipple Flow Coupling Ball Activated Pressure Sub Perforated Spacer Tube No-Go Seating Nipple Pinned Collar Seating Nipple Blast Joint Polished Nipple Sliding Sleeve Hydraulic Retrievable Packer Seating Nipple Ball Activated Pressure Sub Perforated Spacer Tube No-Go Seating Nipple Wireline Re-Entry Guide Weatherford • Permits independent production of each zone • Flanged-up completion for safety • Fully retrievable completion (both packers) for remedial access • Or, the bottom packer may be a permanent packer which serves as a locator for spacing out the completion