CEMENTING & FLOAT EQUIPMENT
Through our Davis-Lynch™ branded downhole well construction and completion tools business, we supply products used in the construction of oil and gas wells. Davis-Lynch’s history dates back to 1947 when they began as a manufacturer of float equipment. Today, the Davis-Lynch product line has expanded to include a full line of Centralizers and primary cementing aids, Multi-Purpose Float Collars, Stage Cementing tools, Inner-String Cementing tools, Inflatable Packers, Flotation Collars, and Cementing Plugs.
EnerQuip represents Forum Energy Technologies Downhole Division in Pakistan. Forum Energy Technologies Downhole division is amongst the top 3 well construction equipment manufacturer of the world and is renowned worldwide for top quality equipment supplied.
In July 2011, Forum acquired Davis-Lynch, LLC to expand its product line in Completion & Cementing. When quality and satisfaction are what you demand, Forum does its utmost to bring you the Davis-Lynch products that you require and deserve.
EnerQuip represents Forum Energy Technologies Downhole Division in Pakistan. Forum Energy Technologies Downhole division is amongst the top 3 well construction equipment manufacturer of the world and is renowned worldwide for top quality equipment supplied.
EnerQuip is successfully supplying FET’s equipment & providing allied well services support to run the equipment supplied through its engineers.
Products offered by EnerQuip/FET include.
- Stage Collars
Continuing our commitment to innovation, Forum’s new Davis-Lynch™ Composite Stage Collar offers improved drill-out performance and superior sealing capabilities for 2 or 3-stage cementing solutions. Utilizing the proven design of our mechanical stage collars, our Composite Stage Collar is a highly-reliable stage tool featuring a high-strength composite opening seat and improved drillability.
Forum Composite Stage Cementing Collar features include:
- Proven stage collar design Davis-Lynch™ has been running since 1993, with new high-strength composite opening seat comprised of material identical to that used in Forum Frac Plugs.
- Over 10% decrease in drill-out time on average.
- Composite opening seat locks against-rotation during drill-out.
- No continuous composite rings left after drill-out to hang up on PDC drill bits.
- Convolute-Tube composite material maximizes burst, collapse and shear strength.
- No continuous filament-wound material in opening seat or opening device, that hinders the PDC bit penetration rate.
- Dimensionally stable composite material with maximum temperature rating to 350°F.
While now established as a field proven tool, this tool continues to be the subject of research and development to find new materials for faster drill-out time, greater PDC bit drillability and better metal-to- metal sealing.
Features of the 778 MC Stage Cementing Collar include:
- Tools can be made from material grades up to 150,000 psi minimum yield, including material suitable for sour gas service.
- All parts are custom fitted and subjected to extensive quality control standards for maximum performance downhole.
- The connection that adjoins the stage collar body and the bottom sub affects a metal-to-metal seal and engages a back-up elastomer seal, the two of which are designed to provide gas-tight pressure integrity.
- No welds are used on any portion of the tool. The reduced length of the tool minimizes the effect of bending stresses.
- The seals providing internal and external pressure integrity are housed in the stage collar body and remain stationary throughout operation, minimizing chances of their being damaged.
- The pressure-relief design prevents fluid trapping and compression between the opening device and the closing plug during the closing phase of the tool’s operation.
- The closing sleeve is held in the closed position by an internal lock ring.
- Both the opening and closing sleeves lock against rotation for easy drill-out.
- A minimum amount of aluminum and rubber are the only materials encountered during drill-out. Plug sets for four different cementing applications are available.
- Effective differential area on the opening sleeve that generates a high opening force while requiring only optimal pressure to do so.
- The ability to open immediately upon the completion of first-stage cement displacement.
- Opening pressure values that can be adjusted at the time of assembly to assure that all inflatable packers or other hydraulic tools present in the casing string will be triggered at the correct juncture.
Forum Energy Technologies’ Davis-Lynch packer stage cementing collar (PSC) helps ensure proper placement of competent cement in the intermediate casing string, while expanding the operating envelope. By combining an inflatable packer and a stage cementing collar, the PSC reduces NPT and well construction costs, while complying with regulatory requirements and minimizing HSE risks.
Reduce Costs
Through packer stage collar or PSC, our clients are able to reduce their construction and NPT costs. On top of cutting costs, PSC also allows you to mitigate HSE risks and comply with standard regulatory requirements. With a packer stage cementing collar, you can ensure cement keeps falling around slotted or pre-drilled liners.
Isolate Zones
PSC can also help you isolate the second stage cement hydrostatic head from the first cement stage. Similarly, you can isolate from pressurized zones and choose a cement placement across interested zones. Through packer stage collar, you can avoid gas migration that might impact primary cement-based jobs and create annular gas issues on the surface.
PSC: One Tool, Diverse Use Cases
The use cases of the packer stage collar are diverse but it serves as a singular tool. For instance, one person can service a PSC and cut out the added costs of another person who would have to purchase a stage collar and inflatable packer from two different companies.
Mechanics of Packer Stage Collar
PSC tool comes with an inner tube that is protected through mechanically end-anchored and spring steel reinforced strips. Both are encased in an outer oil-resistance rubber. The expansion comes into play when you inject fluid straight into the inner tube.
As a result, the injection leads to partial unleafing of all steel strips that stretches to the outer rubber. This, in turn, has a direct impact on a full-length seal which is either cased or has an open hole. In layman’s terms, once the packer continues to expand, the element’s bottom end stretches on top of a ratchet-style mechanism. It is an added feature of the element that mechanically expands in order to provide full support in the event of a hydraulic failure.
Extended Benefits of Packer Stage Collar
Reduces HSE Risk
Another benefit of the packer stage collar is that it reduces and mitigates HSE risk related to trouble zones and misplaced cement jobs.
Zone Isolation
One of the perks of using a packer stage collar is that it allows zonal isolation. It means you can work out trouble zones with just one simple tool.
Reduce Potential Chances of Remedial Cementing
With a packer stage collar, you can minimize the chances of remedial squeeze cementing. You can also cut out the need to enhance cementing plug in the first stage.
Eliminate Flat Time
One of the most advantageous aspects of using the packer stage collar tool is that it cuts out flat time.
Features of Packer Stage Collar
PSC comes with added features that make it more appealing to a diverse range of clients. Packer stage collar runs in a specific sequence, can pump cement for second-stage in an instant, is compatible with water and oil muds, combines two dedicated tools into a single solution, and supports plugs for the first and second stage.
Contact us to learn more about packer stage collar.
- Float Equipment
Forum’s standard design float shoes and float collars are manufactured with the PVTS valve. This valve is a spring-actuated, plunger-type, one-way check valve. It is designed to withstand high temperatures and large volumes of fluids pumped at high flow rates. It also provides an effective seal under both high- and low-pressure conditions when casing is run and cemented in either the vertical or horizontal position.
The valve housing and closure element are made with a phenolic material. High strength concrete is the compound that molds the valve in the machined housing to form a strong singular unit. Despite the high compressive strength of the concrete, and the shear strength of the valve, Forum float shoes and collars are easily drilled with conventional or PDC bits.
Because of its proven performance qualities, the PVTS valve is used in all manual-fill float equipment including double-valve shoes and collars, and all inner-string cementing equipment including the tag-in, screw-in, and latch-in designs.
Since Forum float shoes and float collars are usually manufactured from steel that has a greater wall thickness than the pipe body of the casing string they are run in, they normally have burst and collapse resistance greater than the casing string.
The Davis-Lynch PDQ Shoe Track™ system combines the shoe track into a 6’ single-piece unit with only one casing thread connection needed. Designed to improve open toe cementing and frac completion well designs, the PDQ system is comprised of a 15K back pressure rated four (4) valve system, latch-down wiper plug profile, guide nose options of rounded or eccentric design type made of composite or aluminum materials. Additional options of reamer blades or jetted profiles are also available. The one-piece external case body is designed with a lifting neck profile for ease of safe handling and installation on the rig floor.
FEATURES
- Designed and manufactured in the USA, ensuring premium quality and timely delivery
- Industry proven 15K pressure rated dual double PVTS valve configuration
- Built-in latch-down plug landing receptacle profile for use with FDL latch down wiper plug systems with multiple landing seats for use with multiple size dissolvable balls
- Choice of many high-performance float shoe nose designs in aluminum and composite materials
- Reamer shoe and jetted Nose configuration options also available
- Available in PDC drillable Davis-Lynch PVTS aluminum valves or severe service cast iron valves for extreme well bore conditions, for use with heavy mud weights and high BHST well temperatures
BENEFITS
- Reduction in cost of threaded connections ($1200 – $4000 minimum savings)
- Provides optimal reduced length shoe track integrity (6’ +/-)
- For use with anticipated high differential pressures when running casing and at the end of primary cementing displacement
- Increases usable pay zone length
Improves shoe joint integrity and reduces leak points in the casing string - Four (4) reliable top fill float check valves that provide well control while running casing
- Eliminates need for separate landing collar for latchdown wiper plugs
- Compatible with all mud types (WBM, OBM, and SBM)
- Provides well test set-up options for completion operations
DESIGN HIGHLIGHTS
- A one-piece design with only 1 (one) casing thread make-up connection
- The design includes an OD profile to provide a lifting neck to allow for easy rig handling and casing string make-up on the rig floor
- Designs can match most casing grade materials and casing threads
- Dual Double 15K psi high back pressure float valve design (4 valves) ensures positive sealing in vertical, horizontal, and deviated wells with a mechanically retained viton coated poppet valve and protected valve spring
- Built from field proven Davis-Lynch PVTS Float Valves that have been tested to API 10F Test rating of D24-R10-T400-P15
- The PDQ design covers casing sizes of 4-1/2”, 5”, 5-1/2” and 6”, with larger casing sizes available by request and further design
- Exceptional quality built with full traceability of component materials starting from the mill material certificates to well site delivery
The FET Davis-Lynch new FlowSure™ Float Equipment is designed to maximize reduction of surge pressure when running close-tolerance casing or liners (small annulus). The valve features a large inside diameter to maximize conversion drop ball size. The larger ID allows for longer circulation with harsher fluids at greater pump rates. The larger ID is also less likely to bridge off during run in hole. Precise conversion pressures are factory adjustable from 300psi to 3,000psi, although most prefer a low conversion pressure of 600-900psi. All this with most components made from an easily drilled composite (glass-reinforced epoxy resin) material.
RECOMMENDED CONFIGURATIONS
The recommended configuration for FlowSure™ float equipment is a doublevalve float collar run in conjunction with a guide shoe. This configuration allows for a one or two joint casing shoe track and is more tolerant of large amounts of cuttings or debris entering the casing string. The guide shoe can be configured with angled jets to aid in cement distribution; eccentric noses are available as required. The guide shoe has a composite rod across it’s bore to prevent the piston or tube of the float collar from possibly blocking the flow.
This equipment can be ordered in a Multi-Purpose Float Collar (Type 713-MP) and we suggest it be run with a Cement-nosed Guide Shoe (Type 601 down-jet or Type 602 up-jet) configuration. It is available in sizes 4-1/2” and larger. For extremely heavy weights of casing, please consult engineering to confirm that normal valve/ball/seat configurations can be used.
The valve is roughly 90% composite (plastic) material and 10% cast-aluminum by weight. The only aluminum components remaining are the flappers, the top portion of the piston, the ball seat, and the ring which holds the shear pins.
APPLICATIONS
- Conventional cement jobs onshore and offshore
BENEFITS
- PDC drillable
- PVTS check valve withstands long circulation time
- High back-pressure rating at temperature
FEATURES
- Rounded cement nose
- High quality PVTS plunger style check valve
- Manual-fill
OPTIONS
- Double valve
- Eccentric nose
- Needle nose
- Lug nose
- Up-jets
- Auto-fill
The Davis-Lynch™ 500RM ReamMaster Reamer Shoe features PVTS check valves, milled angled ribs, and an eccentric round nose. Downjet ports improve circulation, turbulence and even distribution for well cementing applications even in challenging conditions. Since Forum’s purchase of Davis-Lynch over 500 Reamer Shoes have been run.
APPLICATIONS
- Onshore and offshore wells with unstable formations
BENEFITS
- Rotation and reciprocation capable, but not required
- Provides superior performance to get casing down through unstable formations
- Not a drill-shoe and will not make a new hole
- PDC drillable
FEATURES
- Eccentric round nose
- Non-aggressive milled ribs with hard-banding
- Manual-fill
OPTIONS
- No valve – guide shoe
- Double valve Composite nose
- Auto-fill
The Davis-Lynch™ 501 float shoe features PVTS check valves and standard cement noses and non-standard noses. Down-jet ports to improve circulation, turbulence and even distribution of fluid for well cementing applications even in challenging conditions. Since Forum’s purchase of Davis-Lynch over 7,750 501 series float shoes have been run.
APPLICATIONS
- Conventional cement jobs onshore and offshore
BENEFITS
- Boosts turbulence for cementing
- Improves circulation for trouble spots
- Helps wash casing to the bottom
- Reduces risk of casing plugging
- PDC drillable
FEATURES
- Rounded cement nose
- Multiple down-jet ports
- Manual-fill
OPTIONS
- Double valve
- Eccentric nose
- Needle nose
- Lug nose
- Up-jets
- Auto-fill
The Davis-Lynch™ 501DV float shoe features PVTS check valves and standard and non-standard cement noses. Down-jet ports improve circulation, turbulence and even distribution of fluid for well cementing applications even in challenging conditions. Since Forum’s purchase of Davis-Lynch over 5,000 501DV float shoes have been run.
APPLICATIONS
- Conventional cement jobs onshore and offshore
BENEFITS
- Provides more security than single valve options
- Boosts turbulence for cementing
- Improves circulation for trouble spots
- Washes casing to the bottom
- PDC drillable
FEATURES
- Rounded cement nose
- Multiple down-jet ports
- Double valve design to maximize protection
- Manual-fill
OPTIONS
- Eccentric nose
- Needle nose
- Lug nose
- Up-jets
- Auto-fill
The Davis-Lynch™ 700 series float collar features PVTS check valves and is equipped with a flat cement surface for landing and sealing cement plugs. Since Forum’s purchase of Davis-Lynch over 24,000 700 series float collars have been run.
APPLICATIONS
- Conventional cement jobs onshore and offshore
BENEFITS
- Superior cement plug sealing surface
- PVTS check valve increases circulation time
- High back-pressure rating at temperature
- PDC drillable
FEATURES
- Load distributor plate for landing and sealing cement plugs
- Box and pin connections standard
- Manual-fill
OPTIONS
- Double valve
- Auto-fill
For subsurface launch applications, Forum has partnered with Schlumberger to provide the 700X – DSEH (Deep Sea EXPRES* Head) Profile Float Collar. It features an engineered cement sheath that can house both a bottom and top DSEH plug that, once in place, prevents rotation during drill-out. Since Forum’s purchase of Davis-Lynch over 1,400 700X series float collars have been run.
APPLICATIONS
- Subsurface Schlumberger DSEH plug launch applications
BENEFITS
- Provides anti-rotation for DSEH plugs
- Faster drill-out times
- PVTS check valve increases circulation time
- High back-pressure rating at temperature
- PDC drillable
FEATURES
- Cement Sheath for DSEH plugs
- PVTS check valve
- Manual-fill
OPTIONS
- Double valve
- Auto-fill capable
- Cement Plug
Available for surface launch applications, Forum offers the Type LAPN (Lockdown Anti-Rotation Profile New Style) plug system. This system incorporates our latest generation of mechanism to prevent plug rotation while drilling out.
APPLICATIONS
- Onshore and offshore surface plug launch applications
BENEFITS
- Easy engagement between plug and collar, as well as between plugs
- Forum’s unique angled tooth design provides a superior lock to standard tooth designs
- Prevents plugs from becoming disengaged by pressure acting on the plugs from below, or being disengaged during the drillout process
- Faster drill-outs with both PDC and conventional drill bits
FEATURES
- Bottom cementing plug with heavy duty inserts incorporated on top and bottom
- Top plug with a heavy duty insert incorporated on bottom
- Heavy duty angled tooth design
- Five-wiper premium quality plugs provide efficient casing wiping
Forum’s Davis-Lynch product line offers 10ksi, 5.500″ Special Clearance latch down cementing plugs that have the ability to pass through restrictions as small as 3.650″ with only 200psi of pump pressure while still effectively wiping the primary casing ID. The “SC” plug delivers the performance of its predecessor while utilizing the patented ratchet latching system made from high strength aluminum that provides sure engagement and anti-rotation. The dual O-ring nose profile delivers a sure seal when engaged in the catch collar or in the receptacle of the bottom plug.
The “SC” latch down plugs are designed to be run in pairs with the bottom plug having a hollow ID and a burst disk that carries a rupture point between 900-1500psi. The top plug has a solid body and nose to deliver the sealing ability that is rated up to 10ksi. The wiper body used on the “SC” plugs is made from highly durable rubber that is resistant to most chemicals found in well bores, ensuring the plug does not degrade as it is being run in hole. These items are available on special order.
FEATURES/BENEFITS
- Provides customer ability to run 5-1/2” casing with restrictions as small as 3.650”
- Easily passes through most “Toe Valves or Initiators”
- Low pump thru pressure less than 200psi
- High strength aluminum parts for trusted performance
- Chemical resistant rubber wiper body for efficient wiping
- Anti-rotational ratchet system to aid drill out
- Double O-ring nose profile to ensure a proper seal
- Top plug latches into bottom plug that latches into the float collar to provide another “check valve” against cement u-tube
- Casing Packers
- Control wellbore migration of gas and fluid.
- Separate multiple zones.
- Prevent unwanted water intrusion.
- Allow gravel packing of multiple zones.
- Reduce hydrostatic pressure during stage cementing.
- Centralize casing.
- Inflation Control Valves
- Knock-Off Plug
- Rubber innertube
- Rubber Outer Cover
- Flexible Steel
- Reinforcing
- Sliding Seal
- Mandrel (Casing Sub) Flow Restrictor Baffles
For casing sizes smaller than 3 1/2″ and larger than 20″, please consult your Forum representative.
- Extended Reach Equipment
The patented Forum Flotation Collar is designed for use in running casing in substantially horizontal wellbores. Incorporated into the casing string, the device serves as a temporary barrier inside the casing. In so doing, it allows the portion of the string below it to be filled with air (no fluid) and the portion above it to be filled with drilling fluid.
Floating the bottom portion of then casing reduces the drag against the wellbore, while filling the upper portion with drilling fluid adds weight to the casing string to push it into the hole. This feature facilitates running casing in highly deviated wells and, in many cases, permits successful casing runs that would otherwise be extremely difficult if not impossible.
Once the opening sleeve is activated by casing pressure, allowing the drilling fluid to displace the air in the lower section of the casing string, normal cementing operations can begin immediately. Additional pressure on the bottom cementing plug releases the DFC assembly so that it can be pumped down to the float collar. The top cementing plug displaces the cement and lands and seals on the bottom cementing plug/DFC assembly.
Unlike earlier devices that must be set inside the casing and then retrieved after landing the casing (requiring one round trip of the drill pipe and spacing the top of the last casing joint at the rotary table), the Forum Flotation Collar is installed in the same manner as a float collar.
Applying pressure to the inside of the casing string is all that is required to release the trapped air at the bottom of the casing string. This pressure is adjustable at time of manufacture to accommodate different pressure requirements.
The Forum Flotation Collar is self-contained and requires no other running, setting or retrieving tools. The inner sleeves of the device provide a good seal for the cementing plug against the float collar, and they are easily drilled out with either PDC or conventional rock bits when drilling the float equipment.
Running casing to depth is challenging in long lateral sections because of the excessive drag forces. To improve casing running capabilities, the CleanBore™ Buoyancy Sub is placed in the heel to trap an atmospheric chamber in the horizontal section of the casing, significantly reducing drag force. Hook load is concentrated in the vertical section, allowing the operator to land strings in ultra-long laterals. With the casing on the bottom, applied pressure activates the CleanBore™ Buoyancy Sub and leaves a fullbore ID for cementing and completion operations.
The CleanBore™ Buoyancy Sub product line utilizes proprietary glass machining and tempering specifications. The result is a high-strength glass that can withstand shocks during handling and well operations, while ensuring complete disintegration upon activation to leave a fullbore tubing ID.
CleanBore™ Buoyancy Sub Advantages
- High Pressure – Strongest single-layer glass, rated over 15,000 psi
- High Torque – Designed to the torque ratings of all commonly used casing connections.
- Precise Activation – Aerospace technology to provide activation pressure accuracy of +/- 5%
- Casing & Liner Compatibility – Designed with the largest running clearances allowing a combination of casing strings to be run. Compatible with all cement wiper plug configurations.
- Single Glass Disk – Less volume of glass to pump through float equipment.
- No Debris – Shatter Glass technology completely disintegrates and eliminates need for debris trap
- Truly Fullbore – Smooth bore after activation and drift larger than the casing.
Perfect Track Record – 290+ runs with 100% success.
- Centralizers & Accessories
Welded Hollow Vane Spiral Centralizer
In applications for running casing or liners in unstable boreholes and rotation is desired, Davis-Lynch™ offers a special type rigid centralizer for these requirements. To provide optimum performance in unstable wellbores, Hollow-Vane centralizers feature positive stand-off, yet intentionally yield at a pre-determined side-force to prevent stuck-casing. These centralizers have a solid type end collar for slipping over the pin end of the casing joint.
FEATURES/BENEFITS
- Made of steel to provide rigidity and toughness over other weaker materials.
- Normally run between stop collars for applications that require rotating casing.
- Ribs are welded to the end collar to provide maximum strength with a generous weld radius and smooth transition to the main rib body that also has an axial radius.
- Typical friction factor is .12-.14 for open-hole. The rib’s smooth OD will not plow in deviated wellbores.
- Spiral Rib shape creates turbulence to optimize mud removal and prevent cement channeling. Straight Rib is also available.
- Hollow Rib shape will deform at higher side forces, typically 30-40,000 lbs, so casing can still be run to total depth even if wellbore restrictions or unstable formations are encountered.
- Hollow-Vane Centralizers are symmetrical, so drag into or out of the wellbore will be similar.
Disrupter®
The Disrupter is a unique composite solid body slip-on spiral blade centralizer. Featuring an advanced design that allows the casing to oscillate in the wellbore, the Disrupter® reduces friction and provides less drag, allowing the casing to easily glide through wellbore deviations and horizontal sections. The Disrupter exploits the negative energy of hole drag, by turning side contact force into applied casing oscillation.
The Disrupter has successfully been run in wells with bottom hole temperatures surpassing 390°F in geothermal applications. Featuring a solid body design made up of a high-grade resin, the Disrupter is able to withstand the typical impact, wear, and heat resistance encountered downhole.
Powered by a Patented Design
- Takes the path of least resistance
- Navigates wellbore obstructions
- Accommodates high DLS and whipstock applications
BENEFITS
- Independent from all formations, completion types, and mud types
- Reduces open hole friction factors by 20+%
- Delivers increased available hook load at total depth by 25+%
- Faster run times and increased trip speed by 15+%
Welded Solid Body Centralizer
Solid-body Welded Centralizers have ribs that are welded to a continuous steel sleeve. The ribs, or blades, may be straight or angled (spiral-vane) to provide flow diversion. Ribs provide sufficient contact with the wellbore to provide centralization but prevent wall sticking. They can be installed stationary to the casing (set screws) or free to rotate. Length of movement is determined by placement of stop devices or length of casing joints.
- Maintain centralization through positive stand-off.
- Provide rugged centralization that is less likely to be damaged when running in the hole.
- Reduce torque required to rotate the casing.
- Straight-vane reduces the drag forces when running casing.
- Low coefficient of friction.
- Spiral-vane provides flow diversion which improves mud
Hinged Non-Weld Bow Spring Centralizer
Davis-Lynch™ Non-Weld Type “NW” centralizers are designed to exceed the performance requirements of API Specification 10D for both starting and restoring forces.
The Non-Welded Turbolizer is a centralizer with metal fins installed on the bows to help induce turbulence in the cement slurry during pumping operations. Like the spring bows, the fins are made of heat-treated alloy steel. This makes them flexible, which minimizes damage while moving downhole. The Davis-Lynch Turbolizer incorporates the same nonwelded end collar to springbow interlocking adjoinment as the Davis-Lynch centralizer.
Turbolizers are available in the same sizes and bow heights as centralizers. As with the Davis-Lynch centralizer, turbolizers can be manufactured with a builtin stop device. These items are available on special order.
Other design features of the Type “NW” Centralizer include:
- Bow springs made of alloy steel which are heat treated and tempered to a hardness of 42-44 Rc ensures proper and consistent spring characteristics.
- End collar hinges that are folded to the inside. This minimizes the collar stretch that tends to occur when centralizers encounter tapers common to some pipe connections.
- A reinforcing rib stamped into the end collar. This strengthens it to ensure maintenance of its round configuration during transport.
- Several different spring bow heights that are available to accommodate most any casing-to-hole configuration.
- Centralizers with built-in stop devices as well as those for unusual sizes available on request.
Hinged Non-Weld Semi-Rigid Centralizer
The Semi-Rigid Centralizer features a unique bow design that allows each centralizer two contact points with the borehole while having low starting and running forces, but very high restoring or centering forces. It is also a non-weld variety and features a bow with dual curves giving the bow an “S” shape. It simultaneously provides features found desirable in both bow-spring and rigid centralizers. Davis-Lynch Semi-Rigid Type “SR” centralizers are designed to exceed the performance requirements of API Specification 10D for both starting and restoring forces.
- As the bow OD is typically very close to hole size, the centralizer has very low starting and drag forces.
- The double profile of the bow results in much higher restoring forces than conventional bow-springs.
- Bows are made from alloy steel, heat-treated and tempered.
- Utilizes Davis-Lynch patented interlocking bow attachment to end collars.
- Can be run in highly-deviated and horizontal wellbores.
- Can be run over casing connections or stop collars.
- Can be supplied with built-in stop device if requested.
- Bows still provide some flex that allow the centralizer to compress through tight spots and severe doglegs unlike a conventional rigid centralizer.
- Can be provided with turbolizer fins to help induce turbulence in the cement slurry during pumping operations.
Hinged Non-Weld Rigid Centralizer
This Forum product features the patented interlocking adjoinment between the end collars and bow springs that is widely used though out Davis-Lynch™ centralizers due to its effectiveness.
Coupling this feature with stamped sheet steel or stamped and welded bow springs results in a low drag, rigid unit that is sought after by today’s operators.
Not only does the Rigid bow centralizer deliver low drag, it also delivers optimum concentricity for cementing operations, and it can be used in cased hole as well as open hole applications with the same results.
These centralizers are offered in a wide assortment of bow sizes to accommodate most casing-to-hole configurations. They can also be configured using a new type of bow that is stamped and does not require welding to become rigid. These bows are fixed to the end collar in the same patented non-welded fashion.
One Piece Bow Spring Centralizer
The Forum One Piece Bow Spring Centralizer is nonweld uni-body bow-type centralizer. These Centralizers are made from a single piece of alloy steel tube that is precision-cut with a laser to form the end collars and bow springs as one unitary body. The bows are then expanded to the desired outside diameter with advanced tooling. Finally, the entire unit is heat treated to maximize the restoring force of the bows as well as provide strength to the whole unit. Optionally it can be coated with various coatings to provide friction reduction, corrosion prevention or protection for hanger seal areas.
- The strongest bow-type centralizer available today.
- Manufactured from tubular steel with closer tolerances that allow for running in tighter annular spaces (close-tolerance wellbores).
- More stand-off than solid-body centralizers in conventional and bi-center wellbores (where the open-hole ID drilled below a casing string is larger than the casing ID).
- As the bow OD is typically the same or only slightly larger than the wellbore ID, drag forces are considerably lower than conventional bow-type centralizers, yet restoring forces are higher.
- Greater flow-by area than most bow-type or solidbody centralizers.
- Easily coated with low-friction polymers to reduce friction factor in extending reach horizontal casing installations, or to prevent erosion due to plating of expensive casing alloys when installed in a corrosive environment. Also coatings can prevent damage to sensitive areas such as hanger seal ID’s, etc.
- Radially curved bows decrease friction and reduce the chance of drag or damage when passing through milled-casing windows.
- Set screws can be integrated into the lower end collar to provide anchoring without the need for a separate stop collar.
Slip On Close Tolerance Rotating Centralizer
Similar to our Slip-on Close-Tolerance Bow Spring Centralizer, however, this version has a fast-rising bow spring to allow running a set-screw stop collar inside the centralizer.
- Set-screw stop collar is run internally so that the centralizer may be pulled into and out of the wellbore for lower starting/drag forces.
- Allows rotation of the casing.
Can be optionally run between stop collars. - Bows are welded flush with end collar to provide maximum strength with minimum clearance.
- Bows are made of alloy steel and are heat-treated and tempered to a hardness that ensures proper and consistent spring characteristics.
Slip on Close tolerance Welded Bow Spring Centralizer
In applications for running casing in close-tolerance wellbores or slim holes, Forum offers a special bow spring centralizer for these requirements. To provide optimum performance in close-tolerance wellbores, these centralizers feature low starting forces and high restoring forces. These centralizers consist of a solid type end collar for slipping over the pin end of the casing joint.
- Available with set screws in the lower end collar for an integrated stop device (standard), so that no separate stop collar is necessary. The end collar with set screws should be run down (toward the bottom of the hole) so that the centralizer is pulled into the wellbore to optimize starting/drag forces.
- Can be optionally run between stop collars for applications that require rotating casing.
- Bows are welded flush with end collar to provide maximum strength with minimum clearance.
- Bows are made of alloy steel and are heat-treated and tempered to a hardness of 42-44 Rc ensuring proper and consistent spring characteristics.
- Typical applications include 5” casing in 6” hole, 7-5/8” casing in 8-1/2” hole, and 9-5/8” casing inside 10-5/8” hole.
- Recommended set screw torque is 20-25 ft-lbs.
Forum manufactures accessory items known as Stop Collars. Stop Collars provide a means of restricting the movement of a centralizer on the joint of casing, when the centralizer is not installed over a casing coupling. One type, known as a Friction Stop Collar (sometimes called a Bolt-Type Stop Collar), is attached to the casing by tightening a bolt that causes the band of steel to grip the casing. The second type is known as a Set-Screw Stop Collar, which slips on the casing and is attached by tightening set screws that grip the outside diameter. Set-Screw Stop Collars are also available with dual-rows of set-screws for extra holding power, known has “Heavy-duty”. Set-Screw Stop Collars are also available in a hinged type.
- Hinged Friction Stop Collar
- Hinged Set-Screw Stop Collar
- Heavy-Duty Set-Screw Stop Collar
- Set-Screw Stop Collar
- Stage Collars
- Float Equipment
- Cement Plug
- Casing Packers
- Extended Reach Equipment
- Centralizers & Accessories