ArcticPassionNews · 2018-08-20 · ArcticPassionNews Aker Arctic Technology Inc Newsletter Improved Double-Acting Ship Better open water features and more on page 3 Solutions for

ArcticPassionNews

Aker Arctic Technology Inc Newsletter

ImprovedDouble-ActingShipBetter open water features andmore on page 3

Solutions fortransportationsystemsChoose right on page 4

Ice managementprotects shipsand floaters atworkHow does it work on page 9

1 / 2011

March 2011

Arctic Passion News

In this issue

2

Aker Arctic Technology Inc will participatein the following events. Come and meet us there.

Front coverThe latest of Aker Arctic's designachievements are five Shallow-DraughtIcebreaking Tugs for STX NorwayOffshore AS.First of the series "Mangystau-1" wasdelivered last August from STX Brailashipyard in Romania and hassuccessfully met the harsh NorthCaspian ice conditions.

March 2011

Pekka SalmiSenior adviser Pekka Salmi retired inSeptember 2010. Pekka served AARCand the companies preceding AARCduring his 40 year long career and cannow enjoy his well earned retirementdays.

Mikko Niini

Announcements

11-14. July

Montreal, Canada

20-23. September

St. Petersburg, RussiaPOAC 2011 Neva 2011

Hall 7

12-16. September

St. Petersburg, RussiaRAO 2011

12-15. April

Helsinki, FinlandArctic Shipping Summit 2011

2-5. May

Houston, Texas

21-24. June

Moskow, RussiaOTC 2011 Mioge 2011

Stand number 1325,hall E

Pavillion 2, hall 1

Page 2 From the Managing DirectorPage 3 Improved

Double-Acting ShipPage 4 Complete solutions for

transportation needsPage 9 Ice management

protects ships and tankersPage 14 Ice pressure

on fixed structuresPage 15 What's upPage 16 Trip to Norway

As part of the Christmas preparations abrief gathering by AARC staff wasarranged to celebrate awards foremployment anniversaries.Mr. Esa Hakanen (in the picture) and Mr.Sami Saarinen were celebrated for theirfirst 10 years with the Group, Mr. KaunoSarkkinen and Ms. Ann-Cristin Forsénfor 20 years, Mr. Mauri Lindholm for 30years and Mr. Mikko Niini for 40 years.

When writing these words for theprevious Arctic Passion News theMacondo well was still leaking and theindustry shocked from the consequencesof the accident. The leak was ratherquickly stopped and the well closed. BPhas to be praised on the fact how wellthey managed to work in finding thesolutions to cut the deepwater leak. Nowthe investigation committees havepublished their reports and authorities inall oil producing nations are reviewingtheir rules, practices and safetystandards.

The offshore industry, as well as theworld shipping, is among the mostglobalised branches of economic activity.The ships and floaters are moved quicklyfrom one ocean to another and theoperators need to cope with variousnational practices. This is one of themajor industry challenges. Thedifferences in rule and regulations overone single border line are welldemonstrated in the Norwegian initiativecalled Barents 2020, where the safetyregime in the North Sea and the RussianArctic are being analysed and comparedin order to find a way towards moreharmonised rule settings.

Similarly the world shipping isencountering the safe ice operationstandards differently in Northern Europe,Canada, the Caspian Sea and RussianArctic. There is today an ongoingprocess led by IMO to find harmonisedpractices, with a goal set for 2012 tosomething called Polar Code,incorporating an effort to find uniformthinking also in the technical guidelinesfor safe ship construction.

These ongoing processes have put anunfortunate time-out in short term forfurther investments in new harshenvironment operations as the industry iswaiting for authorities' attitudes in thepost-Macondo world. On the other handthe new situation has changed theoverall situation dramatically; the trendappears to be that now the operatorhimself needs to start thinking on hisrisks in any planned activity and createhis own risk assessment and his owndecision-making on acceptable risklevels, which then need to bedemonstrated to the authorities.

I expect this trend and these processesto bring rapidly new findings andpotential for new solutions, as well asnew technologies and practices intoharsh environment operations. One ofsuch key activities is rapidly evolvingphilosophies for Ice Management,protective icebreaker operations tomitigate the risks in offshore andshipping operations in icy and cold Arcticconditions. In this newsletter you will findalso articles on how Aker Arctic isparticipating in solving the problems forthese new demands.

Last year we started publishing thisnewsletter as an experiment which ourcustomers had expressed the need for,in order to better follow what we aredoing and how technologies for Arcticoperations are developing. The feedbackfrom our customers has been entirelypositive. Therefore we are nowencouraged to continue with the traditionand you now have in hand the first issuefor 2011. We hope you will enjoy yourreading and learning on how much therestill is room for improvement andpotential for better practices andsolutions in safe and sustainable Arcticoperations.

Towards risk assessmentbased safety ruling

Dear reader,

3

Arctic Passion News March 2011

Comparison of propulsion efficiency in open waterwhen sailing ahead

( )D

0,20

0,30

0,40

0,50

0,60

0,70

SHIP 1 SHIP 2 SHIP 3 SHIP 4 DSME Arctic

Aframax TankerShips 1...4 from Aker Arctic Database:Typical icebreaking ships with open pram type stern,equipped with twin pulling type pod propulsion units

D

The Double-Acting ship concept isdesigned to run ahead in open water andastern in heavy ice conditions. Theactual bow form can be optimized for theselected route and the superior ice goingperformance when running asternreduces the need to use icebreakerassistance. The benefit from the freedomin bow form design is that the Double-Acting Ship has much better open watercharacteristics than conventional icegoing vessels. Anyhow, as a keen seekerof continuous improvements AARCstarted to investigate in co-operation withDSME if it would be possible to developa new type of Double-Acting Ship withfurther improved open watercharacteristics without compromising onice going features.

Twin gondola stern

AARC has extensive knowledge of icegoing vessels and DSME of open watervessels. By combining their knowledgethe companies managed to develop anew hull form that can efficiently be usedboth in ice and in open water.

“The vessel we designed is an Aframaxsize tanker with a completely new type ofice breaking stern. The aft body has twinPOD propulsion, twin gondola type hulland cut-off transom,” says ProjectManager Mr. Risto Kurimo from AARC,who has also been responsible for theproject in AARC.

The twin gondola stern results in highpropulsion efficiency. In spite of a slightlyhigher open water resistance of the twingondola a fuel saving of around 10% in

open water can be reached compared toa conventional open pram type stern withtwin pod propulsion. This improvedperformance in open water is possiblebecause of a very favourable flowinteraction between the stern gondolasand the propulsion units. The successfulfine-tuning of the gondola form means nosacrifices of ice going capability weremade. Running astern the vessel canpenetrate consolidated ridges almostcontinuously with creeping speed and byturning the PODs from side to side.

The vessel is intended for shipping crudeoil from Pechora Sea to Murmansk, butice model tests demonstrated that fromice performance point of view the vesselcould be capable to operate also on KaraSea.

Risto Kurimo is a hydrodynamics

specialist with experience from

shipyards, model testing and developing

Azipods. He is a Naval Architect and has

worked in the industry over 30 years and

at AARC since 2006. In his free time

Risto enjoys boating both at sea and in

Finnish Lake Päijänne together with his

wife and two sons.

Improved Double-Acting ShipAARC is an independent Arctictechnology provider and is working incooperation with many internationalclients, oil companies, shipowners andshipyards in developing new solutions.One of such regular client over theyears has been Daewoo Shipbuilding &Marine Engineering Co., Ltd. (DSME)with whom AARC has recentlydeveloped a new Double-Acting shipdesign with improved open waterperformance and reduced fuelconsumption.

Fuel savings“This has been a two-yearinteractive developmentproject with the customer. Allice model tests have beenperformed in our testingfacility whereas open waterfeatures have been tested atSSPA in Sweden,” Mr. Kurimocontinues. “This highly icecapable vessel works wellalso in open water and clear

fuel savings are achieved byadopting this new twingondola stern form.”

The concept design waspresented at the ArcticShipping conference inMontreal in November lastyear (Sung-pyo Kim, Young-bok Choi and Risto Kurimo:“Hull Form Development forDSME 100k TDW ClassArctic Tanker”).

The newly developed ice breaking twin gondola stern form Model ready for astern running ice tests with pullingtype pods turned for backing position

4


Complete solutionsfor transportation needsDeveloping transportation systems can sometimes last as longas 20 years. AARC follows its customer projects from the earlystages until the operation is running.

”There are three things that set us apartfrom our competitors: the spectra ofservices we offer, the vast time frame weoperate in, and the world's largestdatabase of icebreaking vessels tested inmodel scale and in full scale. No othercompany can offer this in a package,”says Mr. Arto Uuskallio, Sales andMarketing Manager at AARC.

When an oil or gas company starts toconsider developing an arctichydrocarbon field, AARC aims to assist inevaluating different transportation andoperation scenarios and also in selectingand designing the optimum vessel typesfor the operation. Sometimes AARCdesigns have enabled operation byproviding economically feasible andenvironmentally friendly solutions.

“Typically we start working on a project,when basic ice and environmental data isgathered. The target is to form a design

basis for the vessels, platforms andterminals from the beginning in order to

reach the optimum solution. We help ourclients to solve problems at every stageand to choose the right solutionsregarding transportation during the wholecycle,” Mr. Uuskallio explains.

Mr. Uuskallio tells that the time frame fora project development can span from afew years up to 20 years and AARCfollows it the whole time.

“In very long projects the licence holdercan vary over time. We may start theproject with one oil company and thencontinue it with another until the projectfinally reaches a stage, where actualships are built. At that point we maycontinue the co-operation with a shipowner or a shipyard. This offers our

Continuity reduces risks

clients a huge advantage as werepresent continuity in the project.Continuity reduces risks and the overallresponsibility is clearer compared to acase, where there are many partners atdifferent stages of a project.”

“All places are unique and thereforerequire custom tailored solutions,” Mr.Uuskallio says. He illustrates thedevelopment process with an example.

”Oil has been found in a remote arcticarea with no infrastructure. Our clientneeds to find the best transportationsolution in order to get the oil out onthe market as efficiently and safely aspossible and approaches AARC forhelp.

Tools for every stage

AARC's database contains information about ice conditions and correlations generated

from model tests and tests from real vessels. For instance the AARC designed DAS-

ships are the only ones designed and constructed. The above comparison was made

by comparing model tests with real tests.

0

10

20

30

40

50

60

0,0 0,5 1,0 1,5 2,0 2,5

Hi [m]

P [MW]required shaft power Conventional tankers with ice class

Bulbous bow designed for icebreaking

Moderate icebreaking bow

Extreme ice bow

Extreme Double Acting Tanker stern

Mastera/Tempera

T/T Manhattan 1970

T/T Manhattan 1969

Arctic bulbous bow

Ice performance characteristics for tankers in 80.000-100.000 tdw size class (level ice)

5


We need to know project limitations andthen our experts can start work in order togenerate the optimal solution. The firststep is to check our database on theinformation already gathered on iceconditions, bathymetric information andother environmental data in the specifiedarea. Then we analyze what informationis further needed and expeditions togather the necessary data are planned.This phase can take a few years and atthe same time there are usually otherteams exploring e.g. environmentalissues in the area on behalf of the client.”

After this “setting design basis” stageAARC experts evaluate what would bethe best way to transport the oil to themarket. Usually the outcome is to useships as oil quality is kept best that waycompared to pipelines and the clienttherefore gets a better price for the oil.AARC experts further evaluate where theterminal would optimally be locatedtaking into account the effectingparameters together with the customer.Finally specifications for the vessels,assisting icebreaking supply vessels andother installations are made.

“At this stage we start to design theoptimal ship for the operation and othernecessary vessels and installations aswell,” Mr. Uuskallio continues. “When theconcept design process is ready thevessels are tested in our ice modeltesting facility to verify that they fulfil the

requirements we have set jointly with the

client. In the last stage of planning wefinalize the evaluation of the constructioncost.”

When the planning is ready, the oilcompany puts the ships up for charter ortendering. Usually AARC is part of thisprocess too. When decision is madeabout who will operate and build thevessels, AARC can continue to designthe vessels further or act as an advisor

and supervisor during the wholeconstruction process and finally assist infull-scale testing when the vessels aredelivered.

“We provide the full range of servicesand tools at every stage, which isdefinitely beneficial for our customers inmany ways,” Mr. Uuskallio emphasizes.

AARC is proud to have the world'slargest database of tested icebreakersand vessel models. All this derives fromthe long history of building and designingicebreakers in Finland. The follow-upfrom built icebreakers has been verysystematic over the decades andtherefore such a huge amount of data isavailable today. This database enablesdesigners to make accurate performancepredictions of vessels with different hullforms and propulsion systems.

“Our database is unique in many ways.We have gathered information on iceconditions during many years and the

World's largest database

knowledge we have is extensive. Inaddition we have facts based on icemodel tests, but also by testing ships wehave designed that are alreadyconstructed. We have been able tocorrelate results from ice model tests andfull-scale tests for the same ships. Oneexample is the Double-Acting concept,where AARC has developed a totallynew ship concept, which has enabledefficient operations in difficult iceconditions and has reduced the need oficebreakers therefore resulting inconsiderable fuel savings and reductionin emissions,” Mr. Uuskallio says.

“The Northern Sea Route is achallenging topic. It is important toremember that the route has alreadybeen open during summer months butthere is no regular traffic yet becausethere are too many uncertaintiesinvolved. For instance next summeraround 15 ships will use the Northernsea route,” Mr. Uuskallio points out.

Ship operators now prepare for thepossibility to use the Northern Sea Routewhen conditions are favourable andwhen there is a price advantage to shipto e.g. China instead of Europe using theshorter route. Also governments need todo their preparations i.e. assessenvironmental risks; prepare icebreakersand procedures if a ship gets in troublee.g. because of a machinery failure.

Northern Sea Route

�

Russian coastal sea areas according to

how severe ice conditions are

Barents

Sea

Kara Sea

Laptev Sea

East

Siberian Sea

Chukchi

Sea

6


Last year the Northern SeaRoute was open till October,but some years this might notbe the case. The operativewindow is short and changesannually and therefore shipoperators cannot take the riskto plan regular transitshipments yet as they mightget to Asia but not back andthe delay would ruin theirschedules completely.

Uuskallio believes futureshipments in this area willincrease, but in steps only.“Every year more experienceis gathered and the operativewindow extended little bylittle. It depends on thetechnical development ofships but also on marketrequirements and prices inAsia compared to Europe. Inorder to start regular trafficconditions have to be stableand risks low. Regularity is

more important for shipoperators than savings onone trip.”

“The impact for AARC will bethat we need to create new

solutions and also update ourice knowledge and gather ice

data from new areas. Wehave already started toprepare for this so our clientscan remain confident that we

always have updated know-how necessary to guidethem,” Mr. Uuskallio assures.

Approximate correspondence

between Finnish-Swedish ice

class rules and RMRS ice

class is 1 A Super ~ ARC 5.

Varandey is a village by the Pechora Seawhere oil and gas findings were made inthe 1980's.

Starting in the beginning of the 1990's,AARC experts went on several iceexpeditions to Varandey area in order togather information about the area, theclimate and the ice conditions at differenttimes of the year. These expeditionswere made for several clients andpartners. During every trip detours werealso taken in order to get acomprehensive understanding of theconditions prevailing. Based fromVarandey-village ice reconnaissancehelicopter flights were made around thearea to get an overview of the iceconditions and locate possible places forterminals. This knowledge served as a

Arto Uuskallio is a Naval Architect from

the Helsinki University of Technology and

did his Master thesis for the company in

1992, after which he stayed. At that time

he worked as project engineer and went

every year on ice expeditions to

Sakhalin, Varandey and Yamal among

other destinations. In 1999 he

transferred to ABB and worked in sales

for eight years and then led the Azipod

concept development team. He returned

to AARC in 2009 and is now responsible

for sales and marketing.

“My driving force in this work is that it

challenges me every day. Ship building

in general is not an industrial

surrounding but specialist work where

one needs to combine knowledge with

serial work. Working with ice is one

challenge further.”

Arto enjoys biking and swimming during

summer and skiing during winter. His

wife and two teenage kids keep him busy

during free time.

Case Transportation system for Varandey:

Permissible service areas for ships of Arctic ice categoriesCategoryof icestregthe-nings

ENH, M, EaIO + *

: Extreme navigation ( with mean reoccurrence one time per 10 years ): Heavy, medium, easy navigation ( with mean reoccurrency one time per 3 years )

: Independent operation Service is permissible : Service is connected with an

Source: Russian Maritime Register of Shipping

: increased: Icebreaker pilotage : Service is impermissible risk to get damageIP -

Typeof icenaviga-tion

BarentsSea

ENHMea- - - +- * + +- - + +

* + + +

* + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + +

IOIPIOIPIOIPIOIPIOIPIOIP

Arc4

5

6

7

8

9

Arc

Arc

Arc

Arc

Arc

KaraSea

- - - -- - - +- - - +- - * +- - - +

* * + +- - + ++ + + ++ + + ++ + + ++ + + ++ + + +

ENHMa

LaptevSea

- - - -- - - -- - - -- - - +- - - +- * * +- - - +

* + + +- * + ++ + + ++ + + ++ + + +

ENHMa

EastSiberianSea

- - - -- - - -- - - -- - - +- - - +- * * +- - - +

* + + +- * + ++ + + ++ + + ++ + + +

ENHMa

ChuckhiSea

- - - -- - - *- - - -- - * +- - - +- * + +- - + +

* + + +

* + + ++ + + ++ + + ++ + + +

ENHMa

BarentsSea

+ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + +

ENHMa

KaraSea

- - + +* + + +- + + +* + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + +

ENHMa

LaptevSea

- - - +- - + +- - + +

* + + +- + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + +

ENHMa

EastSiberianSea

- - - +- * + +- - + +

* + + +- + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + +

ENHMa

ChuckhiSea

- - + +- * + +- - + +* + + +- + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + ++ + + +

ENHMa

Winter / spring navigation in seas Summer / fall navigation in seas

7


base for evaluating what type of vesselscould fit in this area. By combining theknowledge of prevailing conditions withthe technical knowledge of vessels thatcould function in this area, AARC made atransportation economy feasibility study.

At the same time AARC was developing

AARC made further tests on the loadingand unloading systems and how wellthey worked together

The economically best solution wascalculated to be a transportation systemwith three Double-Acting ships that canmanage without icebreaker assistance.The ships constructed are MT VasilyDinkov, MT Kapitan Grotskiy and MTTimofey Guzhenko.

the concept of the Double-Acting Shipand made different models andperformed tests in the ice model basin.After some quiet years, in 2005 Lukoiland ConocoPhillips formed a companyfor the oil production (Naryan-MarNeftegaz) and asked AARC for a studyon developing a suitable ship forevaluation of the marine transportalternative. AARC was well prepared and

compared several options for them whilethey negotiated with the shipbuilders.

In 2005 thenegotiated deal was transferred toSovcomflot. In 2008 the first ship wasready.

�

The Prirazlomnoye oil field shuttle

transport was agreed with ZAO

Sevmorneftegaz in 2003 to be based on a

"double-acting" ship concept.

The development of the Arctic "double-

acting" ship concept was a long-lasting

evolution, requiring a lot of field data to be

acquired and service experiences to be

gained.

The prototype Azipods were installed in

converted high ice class tankers "Uikku"

and "Lunni", which sailed on the Northern

Sea Route for several years under the

ownership of J/V companies Nemarc

Shipping of Finland and Arctic Shipping

Service in Murmansk. Here "Uikku" is

loading her first experimental cargo from

the Tambey gas field in 1995. The tankers

are today known as "Varzuga" and

"Indiga" under Murmansk Shipping Co

operation.

8


In the beginning of 1990 natural gas hadbeen found in Yamal Peninsula. With theSoviet Union falling apart there was noone to take charge of exploring the area.A group of scientists decided to sellsome of the gas condensate to Finnishcompany Neste Oil Corporation in orderto finance further explorations so in 1995a group from Finland initiated a trip toYamal to load the gas condensate Nestehad bought. Mr. Arto Uuskallio fromAARC was one of the participants on thetrip.

The next ice expedition to Yamal wasmade in 1996 to gather facts from thearea.

In 1998 EU funded a large expedition toYamal for the scientific FP 6 programARCDEV. More than 100 people joined

the expedition including sea men,scientists and business people.

“Neste Oil Corporation bought gascondensate again and wanted also toevaluate economical possibilities in thearea, which was the reason I joined theexpedition,” Mr. Uuskallio tells. “TheARCDEV project was made public andrevealed for the first time to Westernoperators the real cost level oftransporting gas condensate to theWestern markets.”

As seems to be more a rule than anexception in the Arctic, players change,oil and gas companies sell and buy.Neste Oil Corporation decided toconcentrate on refining oil instead ofupstream operations and sold all of itsfield rights in the North of Russia.

Today CB & I Lummus is the companyengaged indeveloping the area. In 2009,AARC agreed with CBI Lummus andNovatek to make a transportation studyin the area as ice knowledge had alreadybeen gathered during severalexpeditions.

The overall LNG plan is that by 2016 gasdeliveries should be going on. In order tomeet this goal ship orders should be inplace in the nearest future.

Making use of its extensive database,AARC has developed a simulationprogram for ice-going ships that can beused in full-mission bridge simulators. Itis based on mathematical calculationsand gives as a result the economicallyoptimal solution for a specific purpose.

First a certain ice-condition at a certaintime of the year is modelled and thenthe vessel specifications are put in. Thevessel is then simulated to drivethrough the ice back and forth whilemeasurements of average speed, used

energy etc. are registered. This can bemade for several dates to get thevariation. The simulator then calculatesfuel consumption, how many vesselsare needed for a certain transportationtask or volume during winter and duringsummer. The results indicate theeconomically best solution. This iscrucial especially for LNG terminals asstopping the production is extremelyexpensive and therefore not an option.Storage is also costly so the bestsolution is to have enough ships for

winter time but not too many forsummer time. The simulator also takesinto account the construction costs. Infor in

ree independently operatingships was the economically optimalsolution for that transportation need.

AARC continues to develop thesimulator for operative purposes andtraining.

stance the Varandey-case (seeprevious page) the calculated resultwas that th

Simulation program calculates the optimal solution

Case Transportation system to Yamal:

Ice expeditions to Pechora Sea were made

during the following years: 1992, 1993, 1998,

1999, and 2006. During some years there

were several different expeditions, both ship

based and land based. The inserted graph

reveals the investigated sea floor and ice

profiles on the river Ob.

2.6 km line from river Ob

-10

-8

-6

-4

-2

0

2

4

6

0 0.5 1 1.5 2 2.5

Distance [km]

[m]

Top of snowIce surface upperIce surface lowerSea bottom

10 020

29

9

Ice Management is about managing theforce induced by ice, which constantlymoves in different directions. Drillingships, tankers or production vessels areall 200-300 metres long vessels. If theywould be required to manage on theirown, they would need to be verypowerful because of their size, whichwould increase the construction price. Adrilling ship also has the riser downwhich means it has to stay almost still inan envelope dependent of the waterdepth. If the vessel moves more than theallowed offset, the drilling has to bestopped and in some cases even thedrilling equipment disconnected. In themost severe ice conditions the vesselhas to be disconnected from the mooringsystem, an operation which ends upbeing extremely expensive and leads to

a stop in operation. In a worst casescenario the anchor chains are brokenand the riser damaged due to a suddenice impact on the vessel. Therefore theoptimal solution is to have a separate icemanagement fleet in order to keep an icefree area around the target at all times.

“There are usually at least two steps inIce Management. We talk about aPrimary Icebreaker and a Secondaryicebreaker. The Primary icebreaker is abig and powerful icebreaker, whichbreaks the outer ice cover into large icefloes. Then depending on the icesituation the primary icebreaker breaksthe large floes into smaller ones or asecond primary icebreaker breaks themfurther. The purpose of the Secondary

How to achieve an ice-free area

�

Ice Management protectsships and floaters at work

The picture shows the principals of ice

management in two stages

1) The primary icebreaker splits the ice

into smaller floes.

2) In this case the secondary icebreaker

uses the propeller wake to flush the ice

sideways to create an ice free area in

front of the protected object, in this case

a drillship.

Each part of this can be tested

separately, and the results can be

evaluated for the whole ice management

procedure, as the efficiency of the

Primary IB, the flushing efficiency of the

Secondary IB and the forces acting on

the protected object.

:

Ice Management means protecting a drilling

ship, FPU or production vessel from ice by

breaking the ice around it into smaller pieces

and keeping an ice-free area around the object

so that no ice can disturb the work.

AARC has made a wide range of tests in order

to get full knowledge about how to manage ice

in different circumstances and has developed

simulation tools to assist is planning of ice

management operations.


ICE FLOW3

2

3

1

1

2

10

icebreaker is to protect the target,e.g. adrilling ship,” Tom Mattson, R&DManager Test Services at AARCexplains.

“Drillships and arctic vessels are hugeinvestments so in order to minimize coststhey need to be optimally designed. Wewanted to gather information for thebenefit of our clients on how to bestmanage ice in different situations anddecided to make a series of tests wecalled the” Ice Management Series”. Westarted from the situation above. Our firsttest was to investigate what can be donewith azimuth thrusters that turn 360degrees. We found out that with the helpof these thrusters a vessel can stand stilland blow ice slowly in a chosendirection. Further we wanted to researchif by blowing the ice away we couldachieve an ice-free area so big, that thedrilling ship could be an ice strengthenedopen water vessel. The results showedthat this is possible. We also found out

Other on-going projects continue todeepen the knowledge.

AARC is not only focusing onicebreakers but also on drillships,mooring systems and floaters with ownice management. One recent study wasconducted on how to improve the icemanagement of a big floater concept.The result showed that this can beachieved by using three thrusters. Theside thrusters keep the floater in placeand the middle thruster blows the iceaway. Another solution is to installthrusters in vertical position, pumping thewater upwards in front of the bow, whichcreates an ice free area in front of theship.

AARC offers its customers optimalvessel designs for ice management indifferent circumstances. With theextensive database AARC has built upand its experienced designers, AARCcan calculate and design optimalsolutions for any purposes. Therefore alot of savings can be achieved in additionto environmental foot print. If the samework

that drifting ice moves very slowlycompared to normal icebreaking. The icedrift speed seldom exceeds 2 knots sothe power needed to keep the icebreakerstill is therefore very small and most ofthe thrust can be directed in the wanteddirection.”

“There are many different kinds ofthrusters, both pushing and pulling, sonext in our series we tested theperformance of various kinds of thrustersin ice and how they differ inperformance. It gives the designer abigger range of flexibility if the choice ofsuitable thrusters is wide when designinga vessel,” Mr. Mattsson points out.

“Sometimes a big bollard pull is neededand a nozzle is used around thepropeller. The problem with the nozzle isthat ice can be clogged. We alsoinvestigated for what circumstances anozzle thruster could be used.Additionally we tried to turn the nozzlearound to a pulling nozzle and found thatthe icebreaking capacity actuallyincreased 30-40% because the ice couldgo through instead of blocking thenozzle.”

“We got very good results on how bigice-free areas we could achieve withdifferent types of thrusters in different iceconditions. This will serve our clients aswe now have an even better knowledgeof ice management than before,” Mr.Mattsson says.

Apart from the Ice Management Series,AARC has learned from many customer

projects on ice management. In one ofthe most extreme projects recently ice-going in 3-5 metres thick ice was tested.

Continuous learning

The optimal solution is green

�

Comparison between calculated, model-scale prediction and

performance confirmed at full-scale trials.


MV-Norilskiy Nickelicebreaking capability ahead Pd = 13 MW

012345678

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

Hi [m]

Vs [m/s] CalculatedModel.scale testsFull-scale trials

MV-Norilskiy Nickelicebreaking capability astern Pd = 13 MW

012345678

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

Hi [m]

CalculatedModel.scale testsFull-scale trials

Vs [m/s]

Clearing width in rubble ice

0

10

20

30

40

50

60

70

80

90

100

Ch

an

ne

lw

idth

[m]

Hi = 3 m Hi = 8 m

Pulling thruster

Pushing thruster

Pulling Thruster + nozzles

Shaft lines + nozzles

Ice managementChannel width at ice drift speed 1 knots

Ch

an

ne

lw

idth

[m]

WATER

LEVEL

TANK BOTTOM

21

00

11

can be done with less power, then bothmoney and environment is saved. AARChas the knowledge of what is needed fordifferent circumstances and cantherefore tell a client what size of vesselwith what kind of power they will needand what design the vessel should be.More and more governments are alsorestricting emissions which can be alimiting factor in the operative window.The optimal solution is also the greensolution.

Reliable testing

“Our testing services are fully reliable.We can confidently tell through ice-testing that a vessel or drilling ship willfunction in the real world in thecircumstances agreed. With our historyof testing we have been able to optimizethe testing facility and verify results byfull-scale testing. By comparingcalculations, ice-testing and full-scaletesting we can confidently say that theycomply. We also double-check all resultsand try to reach as close as possibleinstead of leaving safety margins,” Mr.Mattsson emphasizes.The AARC icetesting facility is the newest one. It haswindows to all sides so it is possible tofollow tests from all directions. Itfunctions well and ice behaves naturally.According to Mr. Mattsson it is the onlyice testing facility that can make 200 mmthick ice in a reasonable time andtherefore correct scaling is achieved.

“Other ice-testing facilities don't doshipbuilding projects and consultingcompanies do not have ice-testingfacilities so they lack the full-scaleknowledge we have at AARC,”Tom Mattsson concludes. �


The underwater carriage with the wet

mooring system. The amount and the

characteristics of the mooring lines can

by changed according to specifications.

Even the angle (simulated different

water depths) of the mooring lines can

be varied. Model position is measured

by four cameras, possible detection in

2D, 3D and 6D of freedom.

“When a client approaches usthey either know what theywant or ask us forrecommendations. Theoptimal solution is acombination of many thingssuch as propulsion, hulldesign, power, turning abilityetc. Often it is also acompromise, as arctic featuresare not good for open wateruse and vice versa,” MrMattsson tells.

One of the pioneers in the recent effort todevelop tailored solutions for drilling inan extended seasonal window in theArctic has been Frontier Drilling, recentlymerged with Noble Drilling in the U.S.AARC has been involved in testing andin the development of two of theirdrillship types; The “Frontier Discoverer”,which was converted in Singaporeaccording to principles created by AkerArctic, and the “Bully”-series for whichShell is co-owner. Several testsmeasuring the horizontal forces througha six component balance, XY-forcemeasurements and turning momentswere made for both of these shipdesigns.

One of the requirements in Arctic drillingis a ship design where no ice is goingunder the flat bottom as no ice is allowedaround the drilling risers. The solutionmade in order to protect the moon poolarea from ice was to equip the bow areawith an edge in the bilge area. This iceprotection solution prevents effectivelythe ice from going under the bottom. Infurther studies AARC found out that theoptimal stem solution is a wedge-bowdesign equipped with an edge and with avertical water flushing system that movesthe ice to the sides. This kind of bow hasbeen tested with six component systemand the model has also been attached tothe underwater turret mooring system.

Movements of this bow type weremeasured to determine the offsets andthe loads on the mooring system.

This efficient self-ice-managing bow formis now proposed to new drillship andFPU projects under preparation in theindustry. International patent has beenapplied for the invention.

12


Trans Arctic Design

Case: Transatlantic primary icebreaker

Case: Frontier drillships

Transatlantic Rederi AB approachedAARC with the task of developing aprimary icebreaker which was not athruster ship. The client also wanted toknow how a shaft line vessel canmanage to make an ice-free area. AARCadded these tests to the IceManagement Series of test.

The vessel designed for Transatlantic isintended for ice thickness up to 2 metres.AARC investigated in what sizes theprimary icebreaker breaks the ice andhow a smaller ship manages behind. Theresults were then compared to anothersimilar icebreaker with another type ofpropulsion. The results showed that shaftline vessels equipped with ductedpropellers are very efficient as primaryicebreakers in ice management tasksand even the possibility to use this kindof vessels as secondary icebreakers isnot excluded. The shaft lined vessels

are a bit cheaper to construct and can beused in a little harsher ice conditions asin multi-year ice. Vessels with Azimuth

thrusters are usually designed for use inone-year-ice.

This ARC 109 ship concept is ready forconstruction.

The AARC, wedgebow and waterflushing in use.

13

Mr. Tom Mattsson has been working with

ice model testing for 27 years. From last

August he is responsible for Research

and Development for test services at

AARC. His work includes being part of

developing hull forms and gathering

parts together for a complete customer

solution when the target is to achieve an

ice-free area in front of a tanker, ship or

a floater.

”I studied ship building and by chance

came in touch with Wärtsilä Arctic

Research Centre, as was the name at

that time. My passion to work in this area

derives from the creativeness it offers

every day. It is necessary to use your

expertise combined with your

imagination in order to create new

solutions as every model test is a

prototype,” Mr Mattson says.

Mr. Mattsson spends most of his leisure

time in outdoor activities with his best

friend, his 12-year old Golden retriever.

240

200

150

100

80

60

40

20

00

Thick and week ice sheets

20 40 60 80 100 120 140 160 180 200

FLEXURAL STRENGTH

ICE

TH

ICK

NE

SS

ExtendedAARC FGX icein multi-yearice simulationin new facility

TraditionalAARCFGX icelimitsin old facility

Ext

ended

AA

RC

FG

Xic

eT

raditi

onal A

AR

CF

GX

ice

The possible range of the

model ice used at Aker Arctic is wide


Mr. Topi Leiviskä has worked three years

at AARC with ice model testing and

measurements. Previously he worked

with similar tasks at the ice laboratory at

the Helsinki University of Technology.

In traditional testing the vessel is attachedto a power and measurement system byelectric cables. This would be impossiblewhen testing several vessels andtherefore a remote power, steering andmeasurement system is required.“Oil companies are especially interested inmulti-model testing as the whole operationin ice can be tested at once. In harsh iceconditions the drilling ship has to beprotected by an ice management fleet andit is necessary to know how ice moves,with what speed and what force. Bytesting the whole process we can becertain to design the optimal solution fordifferent purposes,” says Mr. Topi Leiviskä,Senior Research Engineer at AARC.

“In the system we have developedbattery-driven vessels will be used andmeasurements will be made remotely.One important feature is that the datagenerated needs to be compatible withexisting data in order to makecomparisons. Also model sizes have tobe downshifted so that there is enoughspace in the basin to move.”The new remote measurement systemwill also be useful in operational tests,where an otherwise free moving vesselhas until now been attached by cable tothe measurement system. This willeliminate the risk that the cable hasany impact on the movement.

Multi-model testing starts this springIn traditional ice model testing the vessel model is driven back andforth in the ice testing basin. In multi-model testing several vesselsare tested at the same time. AARC has developed a solution tomulti-model testing, which will be launched this spring.

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To learn more on the icecrushing phenomena againsta compliant stiffened platestructure, near full-scale (1:3)ice crushing tests wereconducted in Aker Arctic's testbasin in spring 2010. The testswere part of a Finnish jointindustry project calledSTRUTSI (Ice-structureinteraction modelling andsimulation) with Technip,AARC and VTT (TechnicalResearch Centre of Finland)and funded by Tekes (TheFinnish Agency for Technologyand Innovation).

The dimensions of the icesheet and the stiffened platewere chosen to represent afull size ship or offshorestructure vertical steel paneldesigned to withstand thecrushing loads of 60 cm thicklevel ice. The dimensions ofthe stiffened plate and icesheet were modelled in a ratioof 1 to 3. In addition, to studythe effects of the stiffness, thetest set-up included apossibility to reduce thestiffness of one stringer inrelation to the others. Theinstrumentation included bothstrain gauges for load

distribution recording at thestiffeners and a tactile sensorplate for accurate directcrushing pressure distributionmeasurements.

In order to have correct andhomogeneous model iceproperties the ice wasmanufactured by a specifictechnique where ice blockmoulds filled with snow wereimpregnated by saline water.Impregnation was done byvacuum technique to preventair-trapping inside the mould.The material of the mouldswas plywood with theexception of the bottom plateswhich were steel to guaranteeeven vertical freezing of ice.

Test procedures

Altogether 22 ice blocks werecrushed with different icevelocities and platecompliancy (stiffness).

Ship or offshore steelstructures under ice actiontypically consist of surfaceplating and supporting framesor stringers. One majorobjective of the tests was tostudy the vertical andhorizontal ice pressuredistribution at the stiffenedplate during the crushingphenomena.

The measured strain gaugedata indicates that withincreasing compliance more ofthe total load is carriedthrough the neighbouringstiffeners, while the icepressure according to thetactile sensor data is relativelyeven in the horizontaldirection. This state persistedeven though the centrestiffener compliance wasincreased,

The well-known horizontallyorientated “line-like” contactprevailed in continuouscrushing (red colour in theFigure 1). The tests alsoindicated that this line-likepressure distribution wasindependent from theunderlying stiffeners within thestructural compliance rangeapplied in these tests.

The performed testssupported the fact that the ice-structure interaction processwith associated loads is acomplicated process which isstill not perfectly understood.Therefore, applying theexisting common practicesand codes for individualdesign purposes should bedone carefully. For example,the new ISO 19906 codeassumes a parabolic or

square pressure distributionprofile through the icethickness. The performedtests indicate that theproposed load profile may bevertically narrower and havehigher local pressure.

“The results from these testsare intriguing, as the appliedmeasurement systemprovides new possibilities toobserve and learn more fromthe ice crushing process,”says AARC's Project ManagerMr. Sami Saarinen, who has

also been responsible for thepractical implementation of thetests and ice preparation. “Theaccuracy level of the resultsfrom these kinds of tests ishigher than in previous cases,which naturally makes themattractive to use when, forexample, applying directdimensioning of the structuresunder ice loading.”

“Now that the unique testprocedures and arrangementshave been successfully trialledin our lab they are availablefor customized use with ourclient projects,” Mr. Saarinenadds.

Results

Future implications

Ice pressure on fixed structures

Examples of tactile

sensor panel

measurements.

Above: line-like

nature of ice

pressure;

Below: Individual

pixel maximum

values achieved

during a test.

Oil rigs and other offshore structures face the challenge ofcrushing ice differently than moving ships. The nearly full-scale tests conducted in AARC's test basin have enableda unique approach to study the local ice load build-upphenomena.

To deepen the understanding of ice-structure interaction,the ice pressure evolution during compression against theinstrumented vertical structure was measured with atactile pressure panel and strain gauges.

100 years of icebreakers from Finland

Television channels NationalGeographic and DiscoveryScience will be covering theamazing evolution oficebreaker technology overthe last 100 years as part oftheir hit engineering seriesBig, Bigger, Biggest.

The production companyvisited AARC to learn about

the R&D process from apioneer in icebreakertechnology. The filming isplanned on MT TimofeyGuzhenko, a ship designedby AARC and owned bySovcomflot as an example ofan advanced ship withicebreaking capabilities.

Evolution ofIcebreakers on TV

15


AARC jointly with KazEcoProject(Kazakhstan) is conducting icemonitoring in the Northeast Caspian Seaduring winter 2010-2011 (November-April). The project is divided into twoparts: underwater ice profiling withsonars and satellite image analyseswhich is being conducted with FinnishMeteorological Institute FMI.

Ice monitoring inthe Caspian Sea

The Offshore Support Journal introducedin 2010 the awards for the best Supportvessel of the year, the best ship owner ofthe year, the Innovation of the year andthe Lifetime achievement award. Theawards this year were presented at theAnnual Offshore Support JournalConference Gala Dinner in mid-February2011.

AARC designed icebreaker Mangystau 1was one of the nominees for bestsupport vessel of this year.

The other

“Naturally it would have been great towin the award, but the fact thatMangystau was nominated is anachievement we are very proud of,” saysChief designer Mika Hovilainen fromAARC.

nominees were Seven Havila,Skandi Aker and Skandi Vitoria. DSVSeven Havila got most votes in theworldwide poll and received the awardthis year. The vessel is owned by a JVbetween Havila Shipping and Subsea 7.

Mangystau 1 nominatedfor best support vessel of 2011

Within the Govern-mental Commissionfor Economic Co-Operation betweenFinland and Russiaa new WorkingGroup for Oil andGas has beenreactivated.

The WG met in January 2011 withRussian oil and gas organisations in theRF Ministry of Energy, under thechairmanships of Sergey Khrushchev(Russia) and Mikko Niini (Finland). A co-operation scheme with the Finnishoffshore industry cluster project IFCOand the Russian organisations was beingplanned.

Last December the Swedish publishinghouse Breakwater Publishing launchedtheir annual shipping handbook FinnishMaritime Index 10-11, in which the mainarticles this time were about Aker Arcticand the 100-year anniversary of the firstFinnish-built icebreaker "Mercator" for

the port of Vyborg. This publishing wascelebrated by AARC customers, partnersand other stakeholders together withtraditional Finnish hot wine "glögi". Closeto eighty guests and employeesgathered in AARC premises to receivethe book directly from the printers. In the

picture Robin Berglund, VTT, RiikkaHietala and Ari Seinä, FMI, TorstenHeideman, ABB Marine and HannaSuutarla, Arctia Shipping, hosted byMikko Niini, AARC

Co-operation with the Russianoil and gas industry

Arctic Passion Newsletter

Aker Arctic Technology Inc

Aker Arctic Technology IncMerenkulkijankatu 600980 Helsinki, FinlandTel. +358 10 670 2000Fax +358 10 670 [email protected]

Editor in chief Mikko NiiniTexts by CS CommunicationsLay-out Kari Selonen

Printed in February 2011 by DMP

’squarterly newsletter

Publisher:

::

:

16


AARC employees' yearly teambuildingtrip was this fall a study trip to Norway.The purpose of the yearly excursion is tofamiliarize employees with a differentenvironment and different actors in theindustry in a relaxed way. Thedestinations chosen always representinteresting places useful for daily work.

All AARC employees gathered in mid-November at the Helsinki-Vantaa airportand boarded the flight to Oslo and thenfurther to Ålesund in the middle ofNorway.

All on-board

After a good night sleep, first on theprogram was an interesting visit to theheadquarters of STX Norway OffshoreAS, followed by a catamaran fjord tour.Norway is famous for its fantastic fjords,which are narrow inlets with steep sidesor cliffs, created in valleys carved byglacial activity. One of the most famousis Geiranger-fjord.“We had the chance to go on acatamaran-tour of the Geiranger-fjord,which was incredible. We were reallylucky with the weather, which was clearwith blue skies so the scenery could nothave been more breath-taking with

snow-capped mountains next to theglittering water,” says Ms. JanaVamberova, Management Assistant atAARC. In the afternoon a visit to STXSöviknes Verft Shipyard was scheduledwhere getting familiarized with a LNGfueled supply vessel topped several ofAARC experts' wish list.The next day included two companyvisits, one to Ulstein Group and the otherto Rolls-Royce. Then followed anotherhighlight of the trip, which was a visit toÅlesund University of Technology andtheir simulator centre. “We havedeveloped a simulator for operative andtraining purposes and bench-markingwith other organisations is useful,” saysMr. Reko Suojanen, R&D Manager atAARC. In the evening a tired but happygroup returned home to Finland.

Breath-taking tripto Norway

AARC employees made a tour on the famous

Geiranger fjord with incredible scenery.

The teambuilding trip included many

interesting company visits.

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