Liner Hanger Selection

Liner Hanger Selection

A Guide for Drilling and Completion Engineers

Disclaimer This document has been developed to help drilling and completion engineers identify the liner hanger equipment best suited for their applications. All information, ratings, and recommendations are based on assumptions that may not apply to your specific objectives or well conditions; therefore, Weatherford recommends that you use this document only as a starting point for communications with Weatherford about your liner needs. Then contact the authorized Weatherford representative for liner systems in your area to design the system that is best for your application: www.weatherford.com. This document does not cover all of Weatherford's liner hanger equipment; it covers the most readily available equipment that is suited for conventional liner applications. Your area's Weatherford liner systems representative may recommend other equipment that is better suited to the region or the application.

Contents

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Liner Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Intermediate (Drilling) Liners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Production Liners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Drill-Down Liners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Extended-Reach Liners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Components of a Liner Hanger System . . . . . . . . . . . . . . . . . . . . . . . . . . Liner-Top Packers/Liner Setting Sleeves and Tie-Back PBRs . . . . . . . . Liner-Top Packers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Liner Setting Sleeves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Liner Hangers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Liner Hangers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic Liner Hangers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cement Displacement Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cementing Packoffs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Liner Wiper Plugs, Drillpipe Darts and Landing Collars . . . . . . . . . . Liner Accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Holddown Subs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Centralizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multi-Stage Cementing Accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . ACP™ Annulus Casing Packers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Float Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Reamer Shoes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DrillShoe™ Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Liner Tie-Backs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tie-Back Seal Stems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tie-Back Packers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Liner Hanger Selection Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Introduction

Introduction Designing a liner hanger installation can be complex because it involves many variables; but the following selection criteria are essential: — Size, weight, grade, and setting depth of casing — Size, weight, grade, connections, and length of liner — Setting depth of liner hanger — Inclination of liner hanger — Proposed trajectory of liner wellbore — Size and weight of drillpipe — Liner application — Completion/stimulation operations after the liner is installed — Loads applied to the liner hanger from the liner weight and from hydraulic operations — Completion and/or wellbore fluids to which the liner may be exposed — Pressures and temperatures to which liner equipment may be exposed All of these considerations must go into the design of a liner system that will meet your needs while remaining within the operational capabilities of the equipment.

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Liner Applications

Liner Applications Liners have many applications and are run for various reasons. For example, they may be the best technical or operational alternative; they may be a cost- or time-saving alternative to casing; or they may help mitigate risk to the well or the environment.

Intermediate (Drilling) Liners Intermediate liners (also called drilling liners) hang or support an intermediate casing string. The liner shoe is meant to be drilled out so that another liner or casing string can be conveyed through it. Because intermediate liners are drilled through, it is possible for them to have a drilling tie-back seal stem stabbed into them. The effective flow area at the liner top changes drastically, without a drilling tie-back seal stem, which will cause inefficient removal of the cuttings; using a tie-back seal stem aids removal of cuttings. These liners are almost always cemented to isolate formations behind them from wellbore fluids. Most are run with a liner-top packer to improve the isolation. Changing wellbore fluids may generate additional load on this type of liner; depending on how the production casing, liner, and tubing are deployed, it is possible that these may see additional forces during completion operations.

Production Liners Production liners are used to hang production casing. Depending on the final well configuration and any completion or stimulation requirements, production liners will probably be exposed to more loads and for longer periods than any other type of liner. Production liners must be compatible with completion products such as completion packers. They must be able to withstand additional loads imposed by completion/production enhancement operations (frac jobs or temperature cycles). They must also be compatible with all fluids and gases to which they will be exposed, including kill fluids, acid, hydrogen sulfide (H2S), and carbon dioxide (CO2). Production liners may be cemented, or they may carry pre-perforated pipe or screens. These liners are usually (but not always) run with a liner-top packer, depending on the completion and the type of well.

Drill-Down Liners Drill-down liners are used to drill some of the hole in which they are deployed. They are run with a DrillShoe™ drilling assembly rather than a guide shoe or float shoe. In addition to hanging capacity and loads applied to the system, considerable torque is applied to the running tool, liner-top packer/liner setting sleeve, and liner hanger with liner in compression.

Extended-Reach Liners Extended-reach liners are extremely long production liners. The biggest challenge they pose is deployment. In many cases limiting factors will be the rig, the pressure to which you can expose the formation, and the pressure piston effect and collapse pressure of the liner.

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Components of a Liner Hanger System

Components of a Liner Hanger System A typical liner hanger system consists of the following components: — Liner-top polished bore receptacle (PBR), also known as a tie-back sleeve or tie-back extension — Liner-top packer or liner setting sleeve — Liner hanger — Cement displacement system consisting of cementing packoff, wiper plug, drillpipe dart, and landing collar — Float collar — Float shoe Running tools are also required for running the liner hanger to bottom, setting it, executing a cement job, and setting the liner-top packer (if applicable). A typical liner running-tool string will consist of the following: — Debris protection system — Packer setting tool — Liner running tool — Retrievable cementing packoff — Plug adaptor — Wiper plug

Liner-Top Packers/Liner Setting Sleeves and Tie-Back PBRs All liners consist of either a liner-top packer or a liner setting sleeve, which connects the liner to the running tool. All liner-top packers and most setting sleeves also are used in conjunction with a tie-back polished bore receptacle (PBR).

Liner-Top Packers For many reasons liner-top packers are used to isolate the liner top after the hanger is set and cementing operations are completed: — Isolation of formation pressure below the liner-top from the casing ID above — Isolation of treating pressures below the liner-top during fracture or acid work — Isolation of formation fluids while the cement sets, helping to stop gas migration — Isolation of lost-circulation zones — The only isolation above the production zone in uncemented liners The liner-top packer can also be used as a tie-back completion or production packer.

Liner Setting Sleeves A liner setting sleeve is used as an alternative to a liner-top packer and provides the means by which the running tool deploys the liner. A PBR is attached for tying back the liner either to surface, with a tie-back packer, or with a scab liner. 6

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Liner Hanger Selection 1st ed. May 2006

Components of a Liner Hanger System

Weatherford Liner-Top Packers Weatherford has three types of liner-top packers: TSP4 Liner-Top Packer The TSP4 liner-top packer is a premium packer that is suited for most applications. The packer features holddown slips and an element that is rated to 7,500 psi (48.3 MPa) at 300°F (149°C) in most sizes. The packer is set by setting down weight through the tie-back PBR. The PBR also supplies a means for liner tie-back operations. It is available with a profile for either the R or the HNG running tool. It is also available with a high-pressure packing element with a differential pressure rating that exceeds 7,500 psi (51.7 MPa). TSP5 Liner-Top Packer The TSP5 liner-top packer is identical to the TSP4 except that it is lock-wired to the PBR; that is, the PBR cannot be backed off even if the liner is rotated aggressively down to depth. This packer is ideal for drilldown or extended-reach applications. WCTSP4 Liner-Top Packer The WCTSP4 liner-top packer is set by setting down weight on the PBR in the same manner as with the TSP4 and TSP5 liner-top packers. The WCTSP4 is available with or without holddown slips and with profiles for either the R or the HNG running tool. The element is rated for 5,000 psi (34.5 MPa) at 300°F (149°C) and is ideal for any application that does not exceed this differential

WCTSP4 liner-top packer with HNG running tool profile

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Components of a Liner Hanger System

Liner Hangers Most liner hangers can be categorized by their setting mechanism, which is either hydraulic or mechanical. Hangers can be further defined by other features or abilities, such as the number of cones and the ability to rotate after the hanger has been set. Cones. In general, a greater number of cones means increased hanging capacity, but it also means longer and more expensive assemblies. Liner system design takes into account more parameters than hanging capacity such as additional loads applied to the liner hanger. A 7-in. liner hanger that can accommodate an 800,000-lbf (3,559-kN) load in 9 5/8-in., 47-lb/ft N-80 casing may carry 7-in., 29-lb/ft L-80 pipe that is only good for 676,000-lbf (3,007-kN). The additional hanging capacity may be required to prevent the hanger from failing should pressure be applied to the liner top. Weatherford's liner hangers are designed to maximize hanging capacity to carry long liners while supporting pressure-induced loads. Rotating versus non-rotating liner hangers. Rotating-style hangers feature a bearing that allows the liner hanger body to rotate independently of the slips and cone. This capability allows rotation of the liner after the slips have been set into the host casing. Rotation of the liner during cementation significantly improves the quality of the cement bond. Rotatable versus non-rotatable liner hangers. Rotatable liner hangers can be rotated to bottom, depending on the liner hanger design and the type of running tool used—not on the liner hanger itself. Conventional mechanical liner hangers that rely on drag springs for setting are non-rotatable, as rotation before setting the hanger can damage the drag springs. Protected slips. Protected slips are slips that are protected inside recesses in the liner hanger. This design shields them from damage even if the liner is worked vigorously to reach setting depth. Protected slips are preferred for drilldown or ream-down applications, where damage to the slips is more likely.

Mechanical Liner Hangers A mechanical liner hanger is set by string manipulation. The simplest mechanical liner hanger setting feature is a J mechanism. This design is easy to operate and reliably sets the hanger: It is picked up and rotated in the setting direction (usually right); then weight is slacked down on the hanger to set it. The main advantage of mechanical liner hangers over hydraulic models is the absence of a port in the body to transmit setting pressure. The main disadvantage of mechanical liner hangers is that deploying them to bottom and in deviated and/or extremely deep wells can be difficult. With mechanical liner hangers, manipulating the liner with the drillpipe through tight spots and setting it are difficult tasks. Rotation while running in hole can be problematic and can damage the setting mechanism (drag spring). In addition, setting mechanical liner hangers is difficult—if not impossible—should the liner become stuck.

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Liner Hanger Selection 1st ed. May 2006

Components of a Liner Hanger System

Weatherford Mechanical Liner Hangers Weatherford’s four main mechanical liner hangers are the CSM, CTM, CRM, and PMR. CSM Liner Hanger The C-series single-cone mechanical (CSM) liner hanger features a single cone and a right-hand setting mechanism. It is easy to operate and has adequate hanging capacity for medium to long liners. CTM Liner Hanger The C-series tandem-cone mechanical (CTM) liner hanger features tandem cones and a right-hand setting mechanism. It functions identically to the CSM liner hanger but provides twice the hanging capacity, which is ideal for all but the longest liners. CRM Liner Hanger The C-series rotating mechanical (CRM) liner hanger features a single cone, a right-hand setting mechanism, and a bearing. The bearing allows for rotation of the liner after the hanger is set. The CRM functions identically to the CSM and has the same hanging capacity, but it also allows rotation of the liner after the hanger is set. PMR Liner Hanger The premium mechanical rotating (PMR) liner hanger features tandem cones, protected slips, and a heavy-duty bearing. It is Weatherford's top-of-the-line mechanical liner hanger. The PMR functions identically to the other mechanical liner hangers but has greater hanging capacity, a heavy-duty bearing, and protected slips.

C-series rotating mechanical (CRM) liner hanger

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Components of a Liner Hanger System

Hydraulic Liner Hangers A hydraulic liner hanger is set by differential pressure across the hydraulic cylinder in the liner hanger. To prevent the hanger from pre-setting during deployment, the hydraulic cylinder is shear-pinned in place. Usually the maximum circulating pressure before the hanger is set is 50 percent of this setting pressure. A typical setting procedure for a hydraulic liner hanger requires dropping a ball, landing the ball on seat, pressuring up against it to activate the liner hanger, and then slacking down weight on the liner hanger. The main advantage of hydraulic liner hangers over mechanical models is that they can be set in high-angle and/or extremely deep wells because drillstring or liner manipulation is not required to activate them. Unlike mechanical models, hydraulic liner hangers do not feature drag springs; therefore, they can be rotated and reciprocated to bottom with the correct running tools.

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Components of a Liner Hanger System

Weatherford Hydraulic Liner Hangers Weatherford’s five main hydraulic liner hangers are the PHR, PHS, CSH, CTH, and CRH. PHR Liner Hanger The premium hydraulic rotating (PHR) liner hanger is Weatherford's top-of-the-range liner hanger. It features protected slips, a heavy-duty bearing, and tandem cones. It has the highest hanging capacity of all Weatherford liner hangers and can be deployed in even the most challenging wells. The hanger can be rotated after the slips is set and is typically run in conjunction with a rotating running tool, which allows vigorous rotation of the liner to bottom. The PHR liner hanger is ideal for drilldown and extended-reach liners. PHS Liner Hanger The premium hydraulic static (PHS) liner hanger is almost identical to the PHR; however, it does not feature a bearing and does not allow rotation of the liner after the hanger is set. CSH Liner Hanger Weatherford's C-series single-cone hydraulic (CSH) liner hanger has a single cone and is suitable for medium to long liners. It can be rotated during deployment; but, with its unprotected slips, the CSH liner hanger is not ideal for drilldown or ream-down applications. CTH Liner Hanger Weatherford's C-series tandem-cone hydraulic (CTH) liner hanger has tandem cones and is suitable for all but the longest liners. It can be rotated during deployment; but, with its unprotected slips, the CTH liner hanger is not ideal for drilldown or ream-down applications. CRH Liner Hanger Weatherford's C-series rotating-cone hydraulic (CRH) liner hanger has a single cone and a bearing. It allows rotation of the liner after the hanger has been set and is suitable for medium to long liners. The CRH liner hanger can be rotated during deployment; but, with its unprotected slips, the CRH liner hanger is not suitable for drilldown or ream-down applications.

C-series single-cone hydraulic (CSH) liner hanger

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Components of a Liner Hanger System

Cement Displacement Systems A liner cement displacement system consists of a cementing packoff, a liner wiper plug, a drillpipe dart, and a landing collar. Each component aids the cementing operation.

Cementing Packoffs A retrievable cementing packoff is used to provide a seal between the liner ID and the running string OD. The seal ensures that cement passes through the liner shoe and also allows for use of pressure to set hydraulic hangers. The main advantage of a retrievable cementing packoff over a drillable one is time savings: No drill-out is necessary. Weatherford's three retrievable cementing packoffs are the RSM, the RKC, and the PBR.

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Components of a Liner Hanger System

Weatherford Cementing Heads Weatherford has three types of cementing heads that it uses to cement liners, including two top-drive cementing heads (the TDH and the RC-TDH) and one rotary rig-type cementing head (the LW). Top-Drive Cementing Head (TDH) The TDH is one of the premium cementing heads on the market. It features two dart valves (so that two darts can be launched), a ball releaser, and a flag indicator sub. It also features a premium swivel so that, as the head is being rotated by the top drive, the connected cement line remains static. The TDH has been DNV certified, and the certification process for current models is under way. The ball releaser and dart valves are all hand operated with wheels on the outside of the cementing head. Remote-Control Top-Drive Cementing Head (RC-TDH) The RC-TDH is the market leader. It has all features of the TDH, but the ball release, dart valves, and indicator sub are all actuated by remote control to significantly enhance safety. The RC-TDH also saves time because rotation can continue as balls and darts are released and the indicator sub is re-set. Lightweight (LW) Cementing Head The LW cementing head is designed for use with rotary-based rigs; therefore it features a swivel assembly beneath all of its primary components. The LW also features a single dart valve and ball releaser and can be fitted with a separate indicator sub. The ball releaser and dart valve are hand operated with wheels on the outside of the cementing head.

Remote-control top-drive cementing head (RC-TDH)

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Components of a Liner Hanger System

Liner Wiper Plugs, Drillpipe Darts and Landing Collars A liner wiper plug is used as a mechanical barrier between the cement and the displacement fluid. It displaces the cement and also wipes the liner ID, removing any cement or debris that may be clinging to it. A drillpipe dart acts nearly identically to a wiper plug except that it displaces the cement in the drillpipe and wipes the drillpipe ID. The drillpipe dart lands in the liner wiper plug and is used to launch it from the bottom of the running tools. The drillpipe dart features an anti-rotation ring, which locks it in position when it latches into the wiper plug. A landing collar is used to stop the wiper plug before it reaches the float equipment. All sizes and models of landing collars feature an anti-rotation mechanism; most sizes and models also feature a latch-down design that provides a positive seal in both directions.

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Liner Hanger Selection 1st ed. May 2006

Components of a Liner Hanger System

Weatherford Liner Wiper Plugs, Drillpipe Darts* and Landing Collars SWP Single Wiper Plug with Ball Seat, Drillpipe Dart and Landing Collar Lite Weatherford's SWP with ball seat is the premium single liner wiper plug. The ball seat in the wiper plug helps land the ball on seat even in the most deviated liner applications. DWP Dual Wiper Plug with Ball Seat, Drillpipe Dart and Landing Collar Lite Liner wiper plug (LWP)

The DWP with ball seat is Weatherford's premium dual liner wiper plug system. It consists of a plug that is launched in front of the cement and a plug that is launched behind the cement. The ball seat in the plug helps land the ball on seat. LWP Liner Wiper Plug, Drillpipe Dart and HLC Landing Collar The LWP is a single liner wiper plug without ball seat. It is used in conjunction with an HLC landing collar, which typically has a ball seat that is used to activate hydraulic liner hangers and running tools. The LWP is applicable for wells without excessive deviation. FLWP Liner Wiper Plug and FLWP Landing Collar The FLWP wiper plug is a full-length wiper plug (or drillpipe dart) that wipes the ID of the liner and the drillpipe. It typically is run as a dual plug system but can also be run as a single plug. The landing collar comes complete with a catcher tube and ball seat. Sub-Surface ReleaseTM Wiper Plugs, Drillpipe Darts and 507P Landing Collar Sub-Surface Release plugs are the best plugs for displacing cement in liners larger than 8-5/8 in. They come in various designs, and both single and dual liner wiper plug models are available. These plugs typically are used with the 507P landing collar. *Weatherford’s drillpipe darts should only be used in strings that meet the following criteria: 1) any ID transition of 1 in. or more must be 30° or less; and 2) any ID transition of less than 1 in. must be 45° or less.

Single wiper plug (SWP) with ball seat

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Liner Accessories

Liner Accessories Weatherford produces numerous liner accessories, the most common being holddown subs, float equipment, and centralizers; but multi-stage cement accessories and ACP™ annulus casing packers are also frequently used.

Holddown Subs A holddown sub is used to prevent the liner from being unset and pushed up the well by hydrostatic or frictional forces. It also can be used to give additional indication of release of the running tool. The main applications are light liners and liners run in conjunction with an inner string.

Centralizers A centralizer is used to help centralize the string during cementing to ensure good cementation and help prevent differential sticking. Weatherford manufactures several kinds of centralizers—from the SpiraGlider® model to solid-body and conventional bow-spring versions. Centralizer placement can be designed and optimized using Weatherford's proprietary CentraPro Plus® software.

Multi-Stage Cementing Accessories These accessories are used for unconventional cementation process and include hydraulically actuated stage collars and mechanically actuated port collars. They are usually used to cement above an ACP packer and prevent the cement from traveling below it. A hydraulic stage collar decreases operating time but also requires drill-out (It is closed by a plug) and allows for only one stage collar to be used. A mechanical port collar does not require drill-out but requires a more complex operation, which includes an inner string.

ACP™ Annulus Casing Packers An annulus casing packer can be used as a mid-string packer and is inflated with either mud or cement, depending on the application. In some formations hydrostatic pressure from the cement can fracture very long cemented liners; but the annulus casing packer provides a reliable seal to protect the liner. An annulus casing packer can also be used for added isolation of problem formations or water-producing formations.

SHE holddown sub

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Liner Hanger Selection 1st ed. May 2006

Liner Accessories

Float Equipment Weatherford produces numerous types of float equipment, including Model 402 float collars and Model 323/329 float shoes, which are ideal for liner applications. These float equipment items include the Sure-Seal 3™ valve, which meets API requirement RP10Fs for float equipment. Weatherford also manufactures auto-fill, differential-fill, and surge-reducing float equipment. These types of equipment can be used to reduce running time, as liner and drillpipe joints do not have to be filled. These types of equipment can also be used to protect the formation from damage induced by surge forces.

Reamer Shoes Model 402 float collar with Sure-Seal 3 valve

Weatherford produces the Diamondback™ reamer shoe, which can be used to ream the liner through difficult sections, such as swelling shale formations. The reamer shoe can feature up to two Sure-Seal 3 valves and comes complete with carbide cutting structures to help open tight spots in the well. If getting the liner to bottom is a concern, Weatherford highly recommends that a Diamondback reamer shoe be run in conjunction with either a Weatherford PHR or PHS liner hanger.

DrillShoe™ Tools A Weatherford DrillShoe assembly can be used in conjunction with a liner to drill additional hole, the length of which depends on the DrillShoe model and the type of formation.

Weatherford’s DrillShoe II drilling assembly

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Liner Accessories

Liner Tie-Backs Sometimes it is necessary to tie a liner back into an existing liner. Weatherford offers several liner tie-back products.

Tie-Back Seal Stems A tie-back seal stem is fitted with molyglass seals and creates an effective seal with the liner-top PBR. Applications for tie-back seal stems include temporary tie-back liners (drilling tie-backs), scab liners, cemented tie-back liners, and tie-back packers that use top-set liner-top packers. Some seal stems feature cementing ports between two of the seal stacks so that the tieback string can be cemented in place.

Tie-Back Packers A tie-back packer features a seal stem, a packing element, holddown slips, and a liner-top PBR. It is run as a second-trip packer when a liner that was run with a setting sleeve requires liner-top isolation. It is also run as a backup in case the original liner-top packer leaks. In most cases a tie-back packer is a reliable and cost-effective alternative to an expensive liner-top squeeze.

Weatherford Tie-Back Packers Weatherford runs two types of tie-back packers: those consisting of a seal stem with a standard liner-top packer and those consisting of a bottom-set tie-back packer run in conjunction with a setting sleeve and liner-top PBR. Weatherford's BSP is a premium tie-back packer that is set by slacking down weight on the running tool and through the setting sleeve. The weight pushes the external components of the BSP against the liner-top PBR, setting the packing element and holddown slips. BSP tie-back packer

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Liner Hanger Selection 1st ed. May 2006

Liner Hanger Selection Process

Liner Hanger Selection Process While liner hanger system design is complex, with numerous variables, the following guidelines should help you understand the issues to consider for your liner applications. The guidelines are based on assumptions that include host casing size and weight, liner size and weight, and buoyancy factors; but many pressure and temperature factors have not been taken into consideration. An authorized Weatherford liner hanger representative will help finalize the design that is right for your well. Hydraulic or mechanical liner hanger. Ease of setting and lowest risk are the determining factors in the selection of a hydraulic or mechanical liner hanger. If the hanger is to be set extremely deep (more than 10,000 ft, or 3,048 m), or if the hanger is to be set in or below a moderately deviated section (more than 30°), a hydraulic liner hanger is recommended. Setting a mechanical liner hanger under these conditions would be difficult. In addition, if a liner must be worked down to depth, a conventional mechanical hanger should be ruled out. For all other applications, either a hydraulic or a mechanical liner hanger can be used. Single- or tandem-cone liner hanger. If the liner weight plus additional loads that may be applied to the hanger exceeds the hanging capacity of a single-cone hanger, a tandem-cone model may be required. If the total load applied exceeds the capacity of a tandem-cone hanger, a premium hanger (such as the PHR, PHS, or PMR hanger) is needed. Working down the liner. If the liner must be reamed, drilled down, or worked through difficult formations, a PHR or a PHS hanger is the best choice. Ball seat location. If any part of the liner is in a highly deviated section (more than 60°), Weatherford recommends locating the ball seat in the wiper plug or in the running tools (achievable with the MX mechanically expanded ball seat). SWP or DWP wiper plugs are recommended for this type of application. For most other applications a ball seat in the landing collar will suffice; however, for larger liners, where the liner ID is greater than three times the ball OD, a ball seat in the landing collar may be difficult. Other factors. Most other factors for selecting a liner hanger and related components are driven more by the client than by any property of the liner. These factors are beyond the scope of this document. The flow charts that follow capture the process of liner hanger selection.

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Liner Hanger Selection Process

4 1/2- x 7-in., 5 1/2- x 7 5/8-in., 7- x 9 5/8-in., and 7 5/8- x 9 5/8-in. Hydraulic-Set Liner Hangers Is the liner longer than the single-cone critical length?

Yes Tandem cone

No Single cone

Would rotation of the LH improve the cement bond?

Yes Premium hydraulic rotating (PHR) LH

No Tandem-cone non-rotating LH

Would rotation of the LH improve the cement bond?

Does the liner have to be worked or reamed down vigorously, or is the liner longer than the tandem-cone critical length?

Yes Premium hydraulic static (PHS) LH

No Casing-bodied, tandem-cone hydraulic (CTH) LH

No Casing-bodied single-cone hydraulic (CSH) LH

Yes Rotating LH

Does the liner have to be worked or reamed down vigorously?

Yes Premium hydraulic rotating (PHR) LH

No Casing-bodied, rotating hydraulic (CRH) LH

Liner Hanger Critical Lengths Size (in.) Single-Cone (ft/m ) Tandem-Cone (ft/m )

4-1/2 x 7 5x7 5,905 1,800 11,811 3,600

5-1/2 x 7-5/8 3,609 1,100 7,218 2,200

7 x 9-5/8 3,117 950 6,234 1,900

7-5/8 x 9-5/8 3,281 1,000 6,562 2,000

Note: Weatherford liner hangers can, in some cases, support significantly longer strings of casing than indicated. The values shown were calculated based on extremely challenging parameters.

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© 2006-2010 Weatherford. All rights reserved.

Liner Hanger Selection 1st ed. May 2006

Liner Hanger Selection Process

9 5/8- x 13 3/8-in. and 13 3/8- x 16-in. Large-Bore Hydraulic-Set Liner Hangers Would rotation of the LH improve the cement bond?

Yes Premium hydraulic rotating (PHR) LH

No Premium hydraulic static (PHS) LH

9 5/8- x 11 3/4-in., 11 3/4- x 13 3/8-in., and 16- x 20-in. Large-Bore Hydraulic-Set Liner Hangers

Premium hydraulic static (PHS) LH

Premium hydraulic static (PHS) liner hanger

Liner Hanger Selection 1st ed. May 2006

© 2006-2010 Weatherford. All rights reserved.

21

Liner Hanger Selection

515 Post Oak Blvd., Suite 600 Houston, Texas 77027 USA Tel: 713-693-4000 www.weatherford.com

Weatherford products and services are subject to the Company’s standard terms and conditions, available on request or at www.weatherford.com. For more information contact an authorized Weatherford representative. Unless noted otherwise, trademarks and service marks herein are the property of Weatherford. Specifications are subject to change without notice. © 2006-2010 Weatherford. All rights reserved.

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