www.claxtonengineering.com

Great Yarmouth - Main Base

ClaxtonBureside HouseNorth River RoadGreat YarmouthNorfolk, NR30 1TEUK

T: +44 (0) 1493 744500E: info@claxtonengineering.com

Aberdeen

ClaxtonTern Place House, Tern PlaceBridge of DonAberdeenScotlandAB23 8JX

T: +44 (0) 1224 452371E: aberdeen@claxtonengineering.com

Dubai

ClaxtonPO Box 262490Jebel Ali Free ZoneGate 5, South SideFZS1 ALO5 Dubai

T: +971 4 8863540E: dubai@claxtonengineering.com

Claxton has been supplying riser systems for over 20 years now,

and the experience we have built up during that time is something that

we believe sets us apart from the competition – that experience,

built up over hundreds of mobilisations, is something that can’t simply

be replicated overnight.

We have a riser and adaptor rental inventory that extends to over 470m of riser, 4,000

ancillary tooling items and a variety of different connection types, including fullbore

API/NACE compliant systems up to 12,200psi. No other company in the market can

offer this breadth of inventory when providing clients with the options best suited to

their projects.

Claxton is not constrained by only being able to offer equipment from one manufacturer

– we genuinely want to supply the most effective system for your project. This flexibility

and depth of inventory, combined with our links to the other specialist riser businesses

in the Acteon Group (2H Offshore and SRP), makes Claxton the subsea riser supplier

to beat.

We look forward to assisting with your projects very soon,

Dannie Claxton Technical Director

“Claxton isn’t constrained by onlybeing able to offer one subseariser technology – the range ofsystem options we offer is in manyways unique”

A genuine riser expert 02

Riser Connectors 04

Riser Handling Tools 05

Riser Tension Rings 06

Tension Systems 08

Rental Tools 09

Scope of supply 10

World First HPHT Riser 14

Deep Panuke Riser 16

Handling the Tension 18

Concentrated Power 20

Systems available now 22

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Full system supply From individual riser joints, through tocomplete riser systems with tensioningequipment, VIV suppression andsubsea connectors, Claxton risersystems will meet the needs of yourdrilling campaign.

Subsea connectors andadaptorsOur riser systems are complemented byour comprehensive inventory of subseaconnectors, H4 connectors, crossoveradaptors, DSA flanges, hubs, liftingadaptors and bolting/gasket stocks.

Rapid mobilisation Our inventory is available for rapidmobilisation from stock and 100%back up can be supplied.

Claxton Riser System Overview

Claxton isn’t constrained by having to supply eitherour own proprietary equipment or the equipment of anygiven manufacturer – meaning we have multiple optionsfor your project, perhaps more than anyone else.

A genuine riser expert

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The support of a wider group

Multiple pressureconfigurationsWe supply systems for pressures upto 12,200psi, with a variety of jointconnection options, from flanges toquick-connect options, through toworld-first shrink-fit technology.

A pioneer in tensioningClaxton has long been a pioneer inriser tensioning equipment,supplying proprietary tension ring andsystem technology that has beenmuch-emulated by our competitors.

Our riser project experience list extendsto over 100 projects since 2005 alone.Email info@claxtonengineering.com foryour copy and compare our record toother suppliers.

Claxton has been supplyingsubsea riser systems since1990 and has pioneered anumber of technologies inthat time – including the firstpositive grip tension ringsand supplying the first-ever12,200psi API/NACEcompliant riser.

Being part of the Acteon Group’s risers,conductors and flowlines division,Claxton has the support of otherwell-known riser specialists.

Our close relationship with 2H Offshore(riser analysis) and Subsea Riser Products(riser design and manufacturing) meanswe have access to riser knowledge noone else can offer – somethingwell-proven by our close collaboration ona number of class-leading technologiesand projects.

12,200psi - Flange 5,000psi - Flange 5,000psi - Quick Connect

Joint Connector SRP Shrink-Fit high API, custom or SRP OilStates MerlinType performance flange high performance flange

Joint Make-Up Optimised make-up Optimised make-up OilStates make-upwith 100% ring-type with 100% ring-type tool & crew bolt tensioners bolt tensioners

Outer Diameter 24" 24" 24"

Inner Diameter 18.3⁄4" 21" 21"

Wall Thickness 2.17" 1.1⁄2" 1.1⁄2"

Operating Pressure 12,200psi 5,000psi 5,000psi

Test Pressure 13,500psi 7,500psi 7,500psi

Coating TSA Coating TSA Coating TSA CoatingNorsok M501-7 Norsok M501-7 Norsok M501-7

Material ASTM A182 F22-80ksi X65, X80 X65, X80

Subsea Vetco DWHD Vetco E, ExF & EWHD Vetco E, ExF & EWHDH4 Connector

Quick Connects Vetco NT-2 & Dril-Quip Vetco NT-2 Vetco NT-2 Radial Bolt package

Riser Tensioning Full suite of tensioning Full suite of tensioning Full suite of tensioningequipment ‘from stock’ equipment ‘from stock’ equipment ‘from stock’

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Claxton holds a full inventoryof riser system surface andsubsea connectors –including high performanceNT-2 quick connector nippleup packages and H4connectors.

BOP Adaptor (NT-2 Box down)

An 18.3⁄4" 15k NT-2 Box down and astandard 18.3⁄4" 15k studded top topermit attachment to the 18.3⁄4"15k BOP.

BOP Adaptor (NT-2 Pin up)

An 18.3⁄4" 15k NT-2 Pin up and astandard 18.3⁄4" 15k studded bottomto permit crossover between the highpressure riser joints and BOP.

Test stump

Our test stumps have an 18.3⁄4" 15k NT-2 pin up to permit testing of theadapter when fitted to the 18.3⁄4" BOP.

Quick Connectors

DWHD

The 18.3⁄4" 15k DWHD H4 Connector isa high strength hydraulic connectordesigned to rigidly attach the BOP orsubsea production tree to the subseawellhead. The connector is operated byhydraulically actuated pistons that drivea cam ring and subsequently asegmented ring of locking dogs into agrooved profile on the wellhead housing.This provides a large axial locking forcethat energises the ring gasket andpreloads the connector to the wellhead.Indicator rod(s) provide visualconfirmation of the locked/unlockedstatus of the connector. (62" OD, 49" Height).

ExF

The 18.3⁄4" 15k ExF H4 Connector isa very similar specification connectorbut is smaller. (51" OD, 41" Height).

Subsea H4 Connectors

Recently we developed a new HydraulicRiser Handling Tool which provides asolution for running, handling andremote pressure testing of a 18.3⁄4"-15mNT-2 Tension Joint to 7,000psi.

The tool was developed for a Norwegianclient and saved 4.5 hours of rig timewith each run – equating to a projectsaving of an estimated £1.8 million.

In addition to cost savings the toolprovides a suite of safety andoperational benefits – removingscaffolding requirements and offeringprotection to the associated riserconnector.

The tool is supplied as a packageincluding dedicated HPU, which isATEX approved.

Riser Handling Tools

Claxton provides a fully hydraulic riserspider designed and manufactured byour sister company Subsea RiserProducts. The riser spider’s compactfootprint allows compatibility withstandard drillfloor layouts, and thedesign is suitable for hang-off in all seastates. Using a twin plate design thetool takes just 12 seconds to engage.No electronic systems exist within thespider - improving field life - and the tooloffers a fail safe positive lock.

Additionally Claxton supplies our ownnon-hydraulic riser spiders, if required.

Riser Spider

We’ve continually strivedto improve the efficiencyand safety of riser runningprocesses – this pageshows just a couple ofexamples of how our suiteof proprietary running toolsdoes just that.

Riser System Connectors & Handling Tools

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NT-2 Box down Connector DWHD H4 Connector Riser Handling Tool

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Claxton has long been theglobal market leader fortension rings. Here’s why…

Claxton has unparalleled experiencein tension rings and systems. Wepioneered the original Positive Griptension ring – which, usinginterchangeable machined slips, isinstalled on slick pipe of all sizes,weights and grades – saving rig time,eliminating ‘space out’ issues andremoving the need for welding.

Positive Grip Tension Rings Slimline Tension Rings

Riser Tension Rings

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The patented Claxton Slimline tensionring can be taken from a containerdirectly onto the drill floor, installedoffline and the riser and tension ring canbe run through the rotary table together,saving rig time. Designed in-house byClaxton, the slimline tension ringmaintains the rugged performance weexpect of more traditional designsdespite being significantly smaller.

Many operators, rigs and drillingcontractors already call Claxton thanksto our…

Unique Experience

Our designs are in successful use bynumerous operators and have beenmuch-copied by the competition.However, the technical expertise thatcreated our tension rings can only befound within Claxton.

Flexible Supply

We have a well-earned reputation forflexibility, so if you have a projectspecific application remember ourtension rings can be dressed with slipsfor non-standard pipe sizes.

Proven Quality

Our tension rings have been proven onrigs working all around the world…meaning you can trust them to performon your project.

Rapid Mobilisation

Claxton has a large fleet of tensioningequipment, much of which is ready for‘from stock’ call-off. Contact us todayto discuss your requirements.

Our tension rings are supplied witha robust toolkit, including bolttensioning equipment – the modularnature of the toolkit enables rapidinstallation and ensures everythingis to hand when required.

Tension Ring Toolkit

Claxton invented thePositive Grip tension ring – a design that hasbeen much-copied aroundthe industry. However theoriginal design can onlybe supplied by us.

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Quality assuredClaxton employs a dedicatedquality team to keep our rentalequipment in first class condition,certified and ready for mobilizationat a moments notice.

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Claxton has supplied manymajor rig operators with risertension systems that mitigateriser stress and enhancefatigue performance.

We can supply complete systems ormodular packages that will interfacewith your existing equipment.

Features:

• Passive or fully active systems available

• Flexible solutions – we’re able to provide either a pushed or pulled load facility

• Supplied with shackles, heavy duty connecting slings and all hydraulic hoses for interface and systemconnections

Riser Tension Systems Rental Tools

• Fast-track and cost-effective build service or ‘from stock’ rentalsupply

• Compact design to ease handling and positioning issues

• Comprehensive site surveys can beundertaken to determine theinterface requirements

• Experienced engineers provided forsystem installation, commissioning and training.

A riser is more than just the jointsthemselves – and whether you choosea flanged or quick-connect systemwe’ve got everything you need to runthe riser successfully.

Additionally our large inventory meanswe can supply equipment to suitnon-standard applications, or supportyou if you encounter an unexpectedinterface issue.

Our large inventory means many rentalitems are readily available:

• Pup and tension joints

• C-plates

• Clamps

• Spools

• Nipple up packages (NT-2)

• H4 connectors

• Handling and running tools

• Umbilicals and reels

• Bolt tension/torque systems

• Overshot connectors

• Hubs

• Inspection camera systems

• Hydraulic power units

• DSAs, crossovers and flanges.

Our riser system inventoryextends to over 4,000 itemsof supporting tools andequipment. We can servicefull riser systems ‘fromstock’ – often with 100%back up.

Riser Tension Systems Rental Tools

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This riser is unique: the world’s firstfull-bore access (18.3⁄4") riser capable ofworking at pressures in excess of12,000psi. Linked to this, the flangesused to connect the individual pipesections will be attached using ashrink-fit process – the first time thistechnology has been used in thisapplication.

The riser will enable the client to drilland complete HPHT subsea wells froma jackup drilling rig employing a surfaceblowout preventer (BOP), which willprovide significant cost benefits andoperational efficiencies.

Designing a riser of this large diameterfor use at such high pressures posesconsiderable challenges. Engineers areforced to use either high wall-thicknessor high-strength steel, both of which arevery difficult to weld, especially in cases,such as the current one, where NACEsour service requirements are cited.The proposed solution, shrink fitting theflanges to the pipes, is the key to thisentire project. Shrink fitting eliminatesthe need for welding; high strength andfatigue-resistant connections can bemade in essentially non-weldablematerials.

2H and SRP have undertaken anexhaustive development and testingprogramme to qualify this technology,which is likely to find broad applicationfor both shallow and deepwater risersystems in the future. (For anexplanation of this aspect of the project,see the attached technical note).

Dannie Claxton, Engineering Director,Claxton Engineering, said, “We haveworked closely with our Acteoncolleagues to offer this very practicalsolution to the challenges of drillinghigh-pressure wells. The first of itstype in the world, the riser is impor-tant because it creates an opportunityto make a cost-effective step-out indrilling practice – one we expectothers to follow.”

2H carried out the initial riser design andanalysis work, and SRP has led thedevelopment of the new shrink-fittechnology. Claxton is ultimatelyresponsible for supplying the riser, whichhas 13 main sections plus fatigue-critical,tapered stress and tension joints.

Shrink fit technology

The riser was designed with keyrequirements: a full-bore (18.¾") riserwith a pressure rating to 12,200psi.Individually, these are not uncommonrequirements. However, when takentogether they pose a considerablemanufacturing challenge.

If a weldable grade, say 65ksi, of steelwere to be used for the riser, a wallthickness of up to 75mm would berequired. Apart from the problems ofmanufacturing pipes of this type, theweight of the riser string would beenormous. Moreover, weldingconnectors of any type to pipe of thisthickness is not straightforward andwould probably result in a poorweld-fatigue performance classification.

Selecting a high-strength steel wouldreduce the wall thickness needed (using110ksi steel would mean a wallthickness of about 30mm), but suchsteels cannot be welded successfully;it is difficult to achieve the requiredphysical properties in the weld.

This problem has been resolved by usinga shrink-fit process to attach the flangeconnectors to the pipe sections. It wasSteve Hatton, founder of 2H Offshore,who had the idea of shrink fitting to avoidthe problems typically encountered withhigh-integrity riser fabrication. Shrinkfitting is not an unusual process in otherindustries but it had never beenproposed for an application such as this.

Hatton said, “The industry has beenseeking a solution to the problem ofwelding high-strength riser joints foryears, and with the current increase inHPHT applications, the problem hasbecome critical. There is significantpotential in this technology to enablethe manufacture of higher-strength,lighter-weight risers with improvedfatigue performance.”

Development and testing

Shrink fitting is a simple process inprinciple. However, there are still severalissues that have to be understood inorder to guarantee repeatableperformance to the level demanded bythe offshore industry, particularly forcritical HPHT riser applications. In view ofthis, a thorough testing programme hasbeen conducted to prove the process

Unique Combination

The equipment inventory and offshoreexperience of Claxton, combined withthe analysis expertise of 2H and riserhardware from SRP has producedsomething unique and powerful – ariser that can, at a stroke, extend theoperating envelope of jackup drilling.This combination of experience andtechnology simply can’t be foundanywhere else.

and confirm the earlier, extensive finiteelement analysis work.

When making the joints, the machining ofcomponent profiles and finishes is tightlycontrolled, as is the heating of the flangebody during the assembly process.Mating the two components is a furtherpractical challenge requiring precisealignment at the instant the two arestabbed together. Simply allowing themated assembly to cool generates ahigh-quality structural connection and agas-tight seal to complete the assemblyprocess. Rigorous load and pressuretesting, witnessed by Bureau Veritas, hasbeen conducted on a series of jointsmade using the 80ksi steel chosen forthis project. (There is no reason,however, why the same process cannotbe used for steels in excess of 110ksi.)

The joints have successfully completedhydrostatic pressure testing up to13,500psi (equal to 90% of pipe bodyyield strength) under various externaltension and bending loads. In addition,gas testing has been conducted to12,200psi.

The integrity of a shrink-fit joint reliesprimarily on the radial contact forcegenerated as the connection cools andshrinks onto the pipe end. The frictiongenerated at the interface is furtherenhanced by geometrical and mechanicalfeatures that 2H has incorporated intothe design. The resulting connectioncapacity is demonstrated to be as strongas the pipe.

World first HPHT Riser

Case study

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Claxton, in conjunction with2H Offshore (2H) andSubsea Riser Products(SRP) recently supplied anultra-high-pressure riser foruse during a high-pressure,high-temperature (HPHT)drilling campaign in theNorth Sea.

This riser represents astep change in drillingpractice – it enables HPHTwells to be drilled from astandard jackup rig and isthe only 12,200psi API/NACE compliant systemavailable today.

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Claxton was successful in its bid to rentout a 5,000psi drilling riser system forthe development of the Deep Panukegas field, 250km off the coast of NovaScotia, Canada. The development plancalled for one new well to be drilled andfour suspended wells to be re-enteredand completed in 44m of water usingthe Rowan Gorilla III jackup rig.

Claxton’s first step was to involve fellowActeon company 2H Offshore to carryout the detailed riser analysis necessaryto determine the riser configuration andsupport system best suited to the rigand the fatigue conditions in the field.

Armed with this information, Claxton setabout withdrawing and testing all thenecessary components for theriser-and-connector package from itsinventory of over 4,000 riser-relateditems in Great Yarmouth, UK. In additionto 24" diameter riser joints fitted with

Merlin connectors, Claxton assembledproprietary positive-grip tension rings,C-plates, an H4 wellhead connector,umbilicals and power units for theprimary and secondary tension systemhydraulic cylinders.

These were then promptly shipped viaLiverpool to Halifax, Nova Scotia, wherethey were united with the jackup. Alsojoining up with the project at that timewas a four-man team from Claxton,which would be responsible for allaspects of the running and retrieval ofthe riser system throughout the drillingcampaign.

Drilling started in January 2010 and wasdogged by consistently poor weather.Nevertheless, the various parties on therig combined in an impressive fashion toensure the successful completion of thefive-well campaign by November 2010.The level of cooperation, teamwork and

willingness to pool ideas and experienceon the rig was cited as one of the mainreasons for the smooth progress of theproject. From the Claxton team’sviewpoint, the project undoubtedly hadthe feel-good factor.

Technical director Dannie Claxtonbelieves the ability to contribute sopositively to projects like this is down tothe company’s 20 years’ experience ofthe riser rental business and the qualityof the people it has to support the useof the systems in the field. But, evenafter all this time and numerous riserrental projects, he admits that “there isstill a great sense of satisfactionwhen everything comes together toensure the sort of success enjoyed bythe Deep Panuke drilling campaign.The project was a credit to the wholeteam. We are delighted to haveplayed a part.”

Deep Panuke Riser

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The Deep Panuke drillingriser project is a perfectexample of something thatClaxton is equipped to doprobably better than anyother company.

Case study

There is still a greatsense of satisfaction wheneverything comes togetherto ensure the sort ofsuccess enjoyed by theDeep Panuke drillingcampaign. The project wasa credit to the whole team.We are delighted to haveplayed a part.

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Handling the Tension

Although from a production perspectivethe North Sea’s best days may now bein the past, the province still generatesgreat examples of offshore engineeringinnovation, as this drilling riser projectfor BG Group plc illustrates.

About two years ago, BG Group plcapproached Claxton to provide aconductor tensioning system to meetsome unusually demandingrequirements. The company wanted todrill in water depths of 78m in theJackdaw field using the Rowan GorillaVI jackup drilling rig – nothing too out ofthe ordinary so far. However, as ChrisKyson, project engineering team leader,explains: “A combination of the waythe rig was configured, theenvironmental conditions in the areaand the fact that BG Group wantedthe system to be capable ofwithstanding the sort of seas nor-mally associated with a 50-yearstormresulted in the need for a conductortensioning system that couldgenerate up to 400 tonnes of load.”

A more common rating for conductortensioning systems in the North Sea is300 tonnes, which can easily beachieved using Claxton’s positive-griptension-ring systems. Presented withthis challenge, Claxton went back to thedrawing board and came up with a newtensioning system: one that would notonly provide the required tensile loadsbut also tilt to reduce the bendingstresses and wave-shock loadingaffecting the conductor.

“We were reluctant to resort to a

welded tension ring in place of ourpositive-grip system because thiswould have meant having to set aprecise space-out distance betweenthe ring and the tension deck,” saysKyson. “It is easy to get this wrongand create knock-on effects thatcompromise the integrity of the otherelements of the conductor system.Instead, we opted to insert amachined rack, 37.3⁄4" long, into theconductor tension joint, which, withits outside diameter of 34", can passthrough the rig’s rotary table.In place of the ring, we have a two-piece adjustable nut that engageson the teeth of the rack and enablesthe space-out distance to be readilyaltered during the conductorinstallation process.”

Perhaps more unusual than the tensionrack was the tilting mechanism that wasalso incorporated into the conductortensioning system to alleviate thewave- and current-induced stressesexperienced by the conductor. Tounderstand how this works, it isnecessary to know that the tension inthe system is generated by a series offour hydraulic cylinders acting againstthe floor of the tension deck upwardsonto a tension plate. The four cylindersare connected between the deck andthe tension plate via either concave orconvex bearing plates: the four on thedeck floor are convex and the four onthe underside of the loading plate areconcave. During operation, the waveand current forces acting on theconductor are sensed and transmittedto the power unit that governs the

movement of the individual hydrauliccylinders. By this means, the anglebetween the deck and the tension plateadjusts (tilts, gimbals and squats) toreduce the effective localised bendingmoment seen at surface by the riser.This reduces stress and thereforeincreases fatigue life.

Before the tensioning system wasinstalled on the rig, it underwent tests inClaxton’s workshops in Great Yarmouth,UK. The tilting mechanism wasthoroughly checked, and the systemwas subjected to a 750 tonnes test load.In October 2007, two Claxtonengineers and a rig crew went out to theRowan Gorilla VI, where they ran theconductor and installed the tensioningsystem. First, the hydraulic cylinders

were fitted to the tension deck. Thesewere then connected to their powerpack and extended by 4-6". before thetension plate was added on top. Theconductor, with its pre-installed racksection, was run through the centre ofthe tension plate via the rotary table;then, once the correct space-out hadbeen achieved, the two-piece adjustablenut was attached to the rack.

“The system was installed withinbudget and on time, andsubsequently performed exactly aswe expected,” says Kyson. “BGGroup must have been impressedbecause it has recommended thesystem to Canadian NaturalResources (CNR), which is down touse the rig next.”

Lockart Campbell, senior subseaengineer with BG Group, confirmedsatisfaction with the system: “Ourpartnership with Claxton has workedwell. I am confident in their ability,both to provide well-executedengineering solutions and to react toarising needs in a helpful andprofessional manner.”

Claxton’s new tiltingtensioning system pushesthe boundaries of what canbe done to help drillers inthe North Sea

The tilting tensioning system is nowback in Claxton’s workshops beingserviced before being reinstalled on therig for CNR. Beyond this contract,Maersk has also expressed an interestin using it. Kyson concedes that this isnot the first tilting tensioning system onthe market, although he is not aware ofanother system that can also generate atension of 400 tonnes. Furthermore, heis proud of the fact that Claxton wasable to provide the ideas, theengineering expertise and the people todevise and then quickly deliver a highlypractical and reliable solution to its latestchallenge.

1918

Case study

A Claxton tension system, similar tothe one supplied for Jackdaw

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Upgrading the riser tensioning systemon the Ensco 102 jackup drilling rig hasmeant installing a new hydraulic powerunit, the specification for which posedsome interesting challenges forengineers at Claxton, the companychosen to design and build it, as projectengineer Will Robinson explains.

“Claxton was contracted by theEnsco 102 to drill an exploration wellin the North Sea and stipulated thatdrilling operations at the givenlocation had to be possible under100-yr storm conditions. A riseranalysis determined that to drill therequired well safely the rig wouldhave to be capable of pulling 400tonnes of tension on the riser.Additionally, the hydraulic cylinderswithin the tensioning system wouldhave to be able to cope with a cyclicdisplacement (sometimes termed a‘squat’) of 8" within a four secondtime period.”

In order to accommodate this degreeof rapid movement the Claxton projectteam had to incorporate an unusualamount of hydraulic energy storage intothe system. They calculated the unitwould require 12 accumulator bottles,each with a volume of 37 litres.Although this was not considered to besuch a problem in itself, it did create aheadache for the designers who knewthe entire unit had to be small enoughto fit into a space on the rig no biggerthan 1.8m wide by 2.0m long and2.0m high.

In fact, packed into the frame of theunit are the 12 accumulator bottles, a450 litre fluid reservoir, four 40:1hydropneumatic pumps (which providethe basic power for the system) plus allthe requisite hoses and valves, whichare all roughly twice the usual bore tohandle the necessarily higher fluid flowrates through the unit.

“It took quite some ingenuity to getall the equipment into the frame,”says Robinson. “One of features ofthe design that helped significantlywas the use of a flat, stainless steelcontrol plate for the unit in place ofa normal console. This saved spaceand made it easier for the hydraulicfitter, as he was able to fit the valvesand pipework to the control platewhile it was on the bench and thenoffer it up to the unit afterwards.”

The unit is also designed to last. Aspainting was never going to be possibleafter the unit was assembled, the unitwas built and tested and then strippeddown for the application of ahigh-performance paint system beforebeing rebuilt, an exercise that addedthree weeks to the production schedule.

The unit was recently fitted to the rig onlocation by Claxton engineers. As thereare now four Ensco jackups that benefit

from Claxton riser tensioning systems,the last word really ought to go to theclient. Speaking on its behalf, JamesForeman, the Ensco 102’s bargeengineer, said, “The new hydraulicpower unit fits well and the crew arefinding it easy to operate. The upgradeto the tensioning system is allowingus to use the jackup to drill a well thatwould normally have required a semi-submersible rig.”

Concentrated Power

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Claxton designers haveused their ingenuity to supplya small but perfectly formedhydraulic power unit toupgrade the tensioningsystem on the Ensco 102jackup drilling rig andsignificantly extend itsoperating envelope.

Case study

The new hydraulic powerunit fits well and the creware finding it easy to operate.The upgrade to thetensioning system is allowingus to use the jackup to drilla well that would normallyhave required asemi-submersible rig.

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Systems available now

Claxton’s riser experienceextends across multipleprojects stretching over twodecades – including over100 riser projects since 2005.The images on this pagerepresent a tiny fraction ofthe equipment we have waiting for call off on yourproject, right now.

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www.claxtonengineering.com

Great Yarmouth - Main Base

ClaxtonBureside HouseNorth River RoadGreat YarmouthNorfolk, NR30 1TEUK

T: +44 (0) 1493 744500E: info@claxtonengineering.com

Aberdeen

ClaxtonTern Place House, Tern PlaceBridge of DonAberdeenScotlandAB23 8JX

T: +44 (0) 1224 452371E: aberdeen@claxtonengineering.com

Dubai

ClaxtonPO Box 262490Jebel Ali Free ZoneGate 5, South SideFZS1 ALO5 Dubai

T: +971 4 8863540E: dubai@claxtonengineering.com