1|11The customer magazine

of ABB TurbochargingSwitzerlandcharge!

A testing time 18From London coffee house to Baden test standDIY to world player 22Rise of ABB’s emissions partner Sailing out of niches 32 Gas engine marine challenge

Coffee and Classification

2 ABB charge! 1|11

From the editor

charge! 1|11

Jonathan WalkerEditorABB Turbo Systems Ltd

The effect of imperatives on engine andturbocharger development takes moreforms than emissions legislation.

The classification societies have beenaround for 250 years, and continue to bethe agent provocateur of improvementsin safety at sea. When they came toBaden recently we witnessed at firsthand how their efforts ensure that newideas benefit life and limb as well asengine performance.

Nonetheless, emissions reduction hasbeen the principal driver of engineprogress for the last 25 years. And thisedition of charge! is the first after the 1st

January 2011. The date marks the first really difficult emissions legislationimposed on ships’ engines. But likemany big changes, IMO Tier II came inmore with a whimper than a bang.

This is typical. The whole emissionsreduction process is reminiscent of aswan on water – easy progress above,frenetic activity below. So our aim is togive readers of charge! a look below the

surface at ABB Turbocharging. They canget an idea of the high pressure that ourdevelopers have been working under inthe build up to IMO Tier II, somethingwhich will only increase as IMO Tier IIInears.

We hope you perceive how emissionsreduction goes to the very heart ofengine technology. When power outputwas paramount, it was enough to pour inmore fuel at the top and get more powerout at the bottom.

Emissions reduction is different. We haveto know exactly what is going on whenfuel ignites in air. The process has led tothe greatest increase in knowledge ofengine combustion processes ever.

ABB Turbocharging is an advancer ofthis knowledge. The A100 and Power2symbolize our progress, as we help solvewhat was once a diesel dilemma – lowerNOx with lower fuel consumption.

Jonathan Walker

A100-LABB’s latest turbochargers make enginescleaner, more flexible and more economical. 04 Perseverance

Our “never-say-die” salesmen and applicationengineers turn around an apparently done deal.14

ABB charge! 1|11 3

Contents

Technology4 A100-L:

At the forefront of 2-stroke engine turbochargingPeter Neuenschwander explains what went into theA100-L that make it so irresistible to engine builders andship owners.

22 “We used to be do-it-yourself inventors”How three Swiss brothers have moved from their ownbackyard to the world stage.

26 ABB Turbocharging and Hug Engineering developInnovative SCR System Compact inter-turbine NOx reduction system sits betweenPower2 turbochargers

Applications14 Perseverance and champagne

Follow the adventures of Arie Smits and his team as theywin a landmark A100 order.

32 Gas engines set sail out of their 100 year nicheRead how gas engines are set to gain new mobility andnew markets.

Operating safety18 A testing time – the classification societies in Baden

The classification societies visit Baden to see that everything is ship-shape with Power2.

News28 People and events around the world as

ABB Turbocharging knows it

Service29 The confusing case of the counterfeit compressor

Close inspection proves copy parts are less than meetsthe eye.

Tips for the operator36 Cylinder outlet temperature vs turbocharger

turbine inlet temperatureManfred Schumm recommends the best exhaust gastemperatures for safe turbine cleaning.

Recipe38 Bibimbap – International recipe No 2

Our culinary journey around the ABB Turbocharging universe takes us to Korea.

A testing timePower2 takes a major step on the road to commercial applications.18 The confusing case …

Service use detection and deduction to provenon-original can never be as good as original.29

4 ABB charge! 1|11

Technology

A100-L: At theforefront of 2-stroke engineturbochargingThe ABB A100-L generation of turbo -chargers has gained rapid market accept-ance. In the following article, the leader of the A100-L development project, Peter Neuenschwander, explains why.Text Peter Neuenschwander, Photography Michael Reinhard, Alex Spichale (pages 10, 13)

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Technology

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Technology

IntroductionThe development of the A100-L turbo -

charger series in 2005 was triggered bythe announcement of the IMO Tier IIemission regimes and market demandfor more powerful 2-stroke engines withreduced specific fuel consumption – thebasic necessity for reduced emissions of the greenhouse gas carbon dioxide(CO2). In initial discussions with customersthe main focus was on reducing emis-sions of oxides of nitrogen (NOX) asrequired by the International MaritimeOrganisation and then on raising enginepower density. However, the recent eco-nomic changes in the maritime industryturned the customers’ priorities fromsteaming fast with powerful enginestowards minimizing fuel costs. Indeed,the adjustments to the engines to meetcurrent market conditions accelerated

the launch of the A100-L series. In spite of these rapidly changing marketdemands and the time needed to developthe turbochargers, we are satisfied thatthe new turbochargers meet the latestrequirements as fully as the initial ones.

Optimum engine performance“Enable engine developers to achieve

optimum engine performance” – this wasa main objective when starting A100-Lturbocharger development. Fortunately,all turbocharger development aims alwaysbenefit the engine builders’ aims: lowerNOX emissions, lower fuel consumptionand increased engine power density.Thus, the direction of the developmentwas clear: high compressor pressureratio, high turbocharger efficiency and a“superelevated” turbocharger efficiencycurve. These clear development direc-

A190-L turbochargers nearing completion.

ABB charge! 1|11 7

Technology

tions for the turbocharging systemremain, to some extent, in contrast to thechallenges related to the combustionprocess in the engine, where measuresfor lowering NOX often compromise fuelconsumption.

However, the performance of theA100-L exceeds the initially requestedtargets and has thus led engine buildersto develop high efficiency versions of 2-stroke diesel engines featuring fuelsavings as high as 2 g /kWh, or morethan 1 % of their typical specific fuel con-sumption. For a 50 MW low-speedengine burning heavy fuel oil, a fuel con-sumption reduction of 2 g /kWh amountsto USD 300,000 over 6000 runninghours assuming a fuel price of 500 USDper ton (500 USD/MT).

Impacts of turbocharger performanceon engine performance

Turbochargers relieve engines in thetask of compressing the air needed forcombustion. The work reduces as theturbocharger compressor pressure ratioincreases. The overall compression workof the engine and the turbocharger isalso reduced due to the cooling of the airin the engine’s charge air cooler. Thehigher air receiver pressure requires morepower from the exhaust gases to drivethe turbocharger. This limits the achiev-able benefit of increased air receiverpressures due to losses related to thehigher exhaust gas pressure. However,the power needed to drive the turbo -charger is minimized with higher turbo -charger efficiency, because it results in the benefit of lower exhaust gasreceiver pressure. Theoretical investiga-

tions showed that air receiver pressurematched to minimized fuel consumptionon modern engines is close to theachievable compressor pressure withA100-L.

Reduced compression work is not theonly benefit of increasing air receiverpressure. Additionally, the final tempera-ture of the air in the cylinder is lower.

The fuel savings of 2 g /kWh or morementioned above are realized via severalmeasures: Firstly, applying a high qualityturbocharger and improving the engine’scharge air cooling, leading to lower airtemperatures in the cylinders at the startof combustion and enabling higher firingpressures in the cylinders. Secondly,adjusting the parameters of the engine’sexhaust valve timing and fuel injection,which finally results in fuel savings com-pared to reference engines while stillcomplying with IMO tier II legislation.

At part and low load the second cru-cial characteristic of the turbochargerwhich leads to enhanced engine per-formance is the “superelevated” patternof the turbocharger efficiency curve. Thispays off in terms of higher reliability andlonger effective lifetime of the hot parts inthe engine, due to better scavenging ofthe cylinders and in lower running hoursof auxiliary blowers.

10 20 30 40 50

Co

mp

resso

r p

ressu

re r

atio

�c [-]

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

V [m3/s]

Volume flow

Operating area for

flexible turbocharging

Optimum compressor pressure ratio

for MCR 21 bar mep

Compressor map of the A190-L with operating line, range for optimum performance at a maximumcontinuous rating of 21 bar mean effective pressure and operating area for flexible turbochargingwith wastegate, VTG turbocharger or “cut-off” of one of several turbochargers.

“Taking the weight offthe engine.”

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Technology

2.0 2.51.5 3.0 3.5 4.0

70

75

65

60

55

50

Compressor pressure ratio

Tu

rbo

ch

arg

er

eff

icie

ncy

�C [-]

�TC

[%]

A190-L

TPL. .-B

4.5

Turbocharger efficiency of the A190-L measured on the turbocharger test rig compared to the previous generation TPL . . -B.

0 20 40 60 80

Engine power

Bra

ke s

pecific

fu

el co

nsu

mp

tio

n

[% MCR]

1, 5

4

3

2

1

2

3, 4

5

6

1 Full load

2 Part load

3 Wastegate

4 VTG

5 TC cut off 1/4

6 De-rating

Basic impacts of optimization strategies on brake specific fuel consumption over engine power,minor differences in fuel consumption neglected.

Optimum operating performanceMarket fluctuations and rising fuel

prices make operational flexibility a priorityfor ship operators in order to ensure prof-itability. One form of flexibility needed isadjusting the ship’s speed to the volumesof freight on offer at a given time and thevalue of the goods loaded. Since the lastglobal oversupply in marine freight capac-ity, “slow steaming” has been a hot topic –i. e. greatly reducing vessel speeds tosave fuel. However, while “turning down”the power of an engine whose fuel injec-tion and turbo chargers were initially opti-mized to the power range needed formedium to high cruising speeds willindeed save fuel, the chance for furthersavings is missed due to operation off thedesign profile and fuel is still wasted.

The traditional way to improve enginepart load performance is to install a tur-bine by-pass or a wastegate valve. Thename wastegate best describes thefunction of this valve – useful energy is“wasted” by diverting it past the turbo -charger turbine when the wastegatevalve is opened. Turbocharging systemswith wastegates save fuel at part and low load, but they cause additional con-sumption at higher load.

On engines with more than one turbo -charger the pressure in the air receivercan be increased at part and low load if one turbocharger is “cut-off”, i. e. byshutting off the flow of exhaust gases toit. With 4-stroke engines this method is well established under the designation“sequential turbocharging”. It allows high

“Flexibility for fluctuatingmarkets.”

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Technology

A170-L turbocharger during assembly.

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Technology

engine performance at all loads butworks best when, like the A100-L, theturbochargers have a wide compressoroperating range, or “wide compressormap”. Indeed, our A100-L turbochargersfeature some of the widest compressormaps ever offered for low speed 2-stroke engines (see compressor mapgraphic on page 7).

If the flexibility to steam with high loadis not needed for a longer period of time,the use of dual maximum continuous rat-ings (MCR) offer further fuel savings forchanging ship operating profiles.

To further facilitate applications whereturbocharger cut-off is specified, theA100-L can also be supplied with theoption of sealing air. This option can alsobe used for dual MCRs on engines inlarge container vessels with three or fourturbochargers.

In both methods described, air receiverpressure is boosted compared to a standard turbocharging system. This isachieved by compensating the lowerflow of exhaust gases at low engine loadby increasing their pressure ahead of theturbine via a reduced total turbine area.

This is also the principle of turbo -chargers with variable turbine geometry(VTG), in which adjustable vanes aheadof the turbine increase the pressure ofthe exhaust gases by reducing turbinearea and hence the speed of the turbineand compressor. VTG is already appliedwith single and twin turbocharger layoutson small and medium sized 2-strokeengines, but can also be applied withthree or four turbochargers.

Turbocharger availabilityThe A100-L turbochargers have been

uncompromisingly designed for low-speed 2-stroke diesel engines. They havebeen optimized for excellent thermody-namic performance and high availability.In this context high availability meanshigh reliability during operation, the abilityto rapidly inspect blades and ease ofservicing when scheduled exchangeapproaches.

In thermodynamic terms two guide-lines were followed. Firstly, the aerody-namics of the casings and guide vanesas well as the rotating blades were thoroughly optimized. Secondly, thedesign was strictly transferred to pro-duction to avoid introducing losses atedges, etc. In terms of service-friendli-ness, field experience with the A100-L’spredecessor, the TPL . . -B, was evaluated.It showed that the rotor block was sel-dom removed as a unit for service workand that this capability is not needed.

This allowed a more compact design,resulting in faster dismantling andreassembly. However, well proven fea-tures like, for instance, squeeze oildamped radial bearings and a floatingdisk for the axial bearing, were retained.

Both design targets – superior per-formance and rapid servicing – wereachieved by concentrating on the essen-tials. The result is a robust, efficientand – in the best sense of the word –“simple” turbocharger design.

Service friendlinessIt is recommended that the condition

of the compressor and turbine stageblades of the A100-L be inspected after18,000 operating hours. The ABB Turbo -charging Service organization offers endusers examination and appraisal of thesecomponents. The checks can be donequickly due to the inclusion of accesspoints for an endoscope at the gas inletand outlet casings.

Final examination and documentation of the endoscopic inspection results.

“As simple as possible, as complex as necessary.”

New compressor stagesIntegrated lubrication oil tankTPL . . -B bearing technologyNew turbine stagesTurbine dry cleaningBearing casing footGas outlet casing footAir outlet silencer (optional)

1

2

3

4

5

6

7

8

1

2

3

3 4

5

6 78

Turbocharger cross section.

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Technology

Product range of A100-L.

5 10

A165-L A170-L A175-L A180-L A185-L A190-L

15 20 25 30 35 40

Volume flow

Co

mp

resso

r p

ressu

re r

atio

�C [-]

4.7

4.6

4.5

4.4

4.3

4.2

V [m3/s]

The A100-L compressor has some of the widest maps ever offered for 2-stroke engines.

Servicing has to be scheduled for the bearings at exchange intervals of36,000 operating hours. For the rotatingparts, exchange has to be planned after100,000 operating hours.

When reading these figures, it shouldbe noted that the rotating parts can be used for approximately seventeenyears based on 6,000 running hours peryear! “For all makes

and models.”

The A100-L product range Appropriate frame sizes of A100-L

turbochargers are available “off-the-shelf”for all state-of-the-art-models from allbuilders of 2-stroke engines, from thesmallest five cylinder 35 cm bore enginesup to the largest fourteen cylinder 98 cmgiants. In the process known as “appli-cation engineering”, the compressor andturbine performance characteristics ofeach A100-L frame size can be precisely

adjusted for all engine characteristicsand ratings due to the fine stepping ofthe exchangeable parts needed for“matching” turbocharger performance toengine performance.

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Technology

Engine with power turbine: Benefit when using A100-L turbochargers instead of TPL . . -B.

64 66 68 70 72 74 76

[%]

5

4

3

2

1

0

Turbocharger efficiency

Po

wer

turb

ine o

utp

ut/

en

gin

e p

ow

er

[%]

+ 40 % power turbine output

A100-L

TPL. .-B

A175-L turbocharger with VTG: The VTG control unit is mounted on the turbocharger.

“For maximum poweroutput and minimum fuelcost.”

OptionsIn terms of turbocharging, optimum

engine operation depends on achievingappropriate air receiver pressure. Airreceiver pressure changes for a givenload with the ambient temperature andpressure of the air. Variable turbinegeometry can compensate these influ-ences. Further circumstances requiringcompensation of changing engine loadsto achieve optimum engine runningresult from the variations in the draughtof the ship due to different payloads or varying seawater densities, winds,currents and hull conditions (fouling).

2-stroke diesel engines achieve theirmaximum efficiency when combined with

a power turbine. The power turbine is fedwith exhaust gas energy not needed todrive the turbocharger turbine. The sur-plus exhaust gas energy increases dis-proportionately as turbocharger efficiencyrises. It increases proportionally with thedifference between the effective turbo -charger efficiency and the minimum effi-ciency needed. Hence, A100-L turbo -chargers are an optimum choice forexhaust gas energy recovery systems.They provide up to 40 % extra power onthe power turbine shaft compared to cur-rent waste heat recovery systems.

Engine and turbocharger noise canaffect occupational health. The turbo -chargers of the A100-L series emit lower

“Compensating wind,weather and draught.”

ABB charge! 1|11 13

Technology

noise than their predecessors even intheir standard configuration.

To further reduce noise emissions orto save first costs in terms of air receiverinsulation, an optional air outlet silenceris available.

OutlookThe A175-L with variable turbine

geometry is already in service on the“Green Ship” Alexander Maersk, where itis an enabling technology of the innova-tive “EGR” exhaust gas recirculation NOx

reduction method targeting compliancewith the IMO Tier III.

Selective catalytic reduction (SCR) isanother method for achieving compliancewith IMO Tier III emissions limits on NOX in ECAs. The operation of 2-strokeengines with SCR reactors installedbefore the turbine requires a variable element, e.g. VTG, air wastegate, SCRbypass, etc. to maintain stable engineoperation over the whole load range dueto the large thermal capacity of the SCR reactor. VTG technology can readilycompensate certain effects of thermallag and assist stable engine operation ina fuel efficient manner.

ConclusionThe first A100-L turbocharger has

already logged 9,200 successful runninghours. At the time of writing 60 units arewith customers and a further 200 unitsare on order or already specified. Theturbocharged engine power totals 4 GW.It is gratifying to know that the markethas so readily accepted the A100-L gen-eration and we are convinced that theA100-L with its various options can servethe 2-stroke engine market’s needs inthe coming years.

The main engine’s EGR system canbe switched on and off depending on theemissions specified at a certain location– IMO Tier III specifies the same NOX

levels as IMO Tier II on the high seas butan 80 % reduction in waters near centersof population and areas of environmentalsensitivity (Emissions Control Areas orECAs). A key factor for satisfactory EGRoperation is achieving the proportions ofinert gas, fuel and charge air for whichVTG is ideal. The adjustable area of theturbine and the wide compressor map,combined with high turbocharger effi-ciency, facilitate very close control of airsupply on the one hand and full poweroperation on the other.

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0

100

105

95

90

85

80

Compressor pressure ratio

Su

rface s

ou

nd

pre

ssu

re level at

1 m

dis

tan

ce

�C [-]

[dB (A)]

A190-L

TPL 85-B

Air outlet silencer of the A190-L during assembly.Noise level of the A190-L compared to the TPL 85-B, both without air outlet silencer at the turbocharger test rig.

“Ready for today andready for the future.”

“A friendly working environment.”

14 ABB charge! 1|11

Applications

Perseverance andchampagneA story that could have been scripted in Hollywood: How ArieSmits, with the help of his untiring team, secured a seeminglylost order for ABB Turbocharging and set a milestone for thenew A100 turbocharger generation.

Text Daniel Bütler, Photography Chang-Hoon Yu

Arie Smits and his team havehad some tough nuts to crackduring his 25 years with ABB.Nevertheless, the autumn of

2010 will stand out in his career as a timethat put all of his sales and business talents to the test. The opening scene ofthis particular “thriller ” takes us back tolast August, when ABB Turbocharginglearns that NOL, a major container vesseloperator based in Singapore, is planningto build ten large container vessels. Theorder, and especially the size of the pro-ject, attracts the immediate attention ofABB Turbocharging’s head office inBaden. “This project was given the high-est priority from the start,” remembersArie, who has headed up the company’sglobal 2-stroke turbocharger businesssince 2001.

From de-rating to full ratingAt this point, Arie adds some back-

ground to the story: “The carrier requestedan engine design that allows derating aswell as fully rated output. One of theways shipping firms can keep their fuelcosts low in a difficult economic climateis by ‘slow steaming’, meaning that ves-sels sail at greatly reduced speeds.When times improve, the engines can berun again at high load. Achieving thesevery different operating modes involveschanging an engine’s turbochargers to anew specification. Normally, this changeof specification involves exchanging therotor and nozzle ring, among other parts,all at considerable cost.”

The order for ten 12K98 engines wasplaced in the autumn of 2010 with Koreanengine builders Doosan (six units) and

Hyundai Heavy Industries (four). Bothengine builders initially specified a com-petitor’s product to turbocharge theengines. “It looked at first like a donedeal,” remembers Arie, “and that we hadno chance. So, what now, walk away, orraise our game?”

The ABB Turbocharging salesmenand application engineers swung intoaction, moving, it could be said, them-selves from “de-rated” to “full rating”.Driving this effort was a “trump card” –ABB’s brand-new A190-L turbocharger.The A190-L offers two very significantadvantages in the case at hand: anunprecedentedly high efficiency – over75 % – and wide compressor maps thatpromised changing from de-rating to fullrating without exchanging parts. The turbochargers remain in place, no time is

ABB charge! 1|11 15

Applications

Arie Smits at the dockside inSingapore harbor, one of the main locations in the NOLslow steaming sales epic.

16 ABB charge! 1|11

Applications

wasted on dismantling and rebuildingand no unnecessary expense is incurred.

The Flying Dutchman takes offArmed with all the advantages of the

A190-L, Arie Smits now began what helikes to call “offensive marketing” – he goton a plane to Asia. “Face-to-face discus-sions are the only way to sell,” he says,adding with a grin that he travels wellover 100 days a year and that “if there isanyone who can claim to be a FlyingDutchman, I guess it could be me.”

Moving to the next movie location, inOctober 2010 Arie, together with NickYong and his team from ABB Singapore,visit the head office of NOL. “We hadlong, intensive discussions with theirsenior management, during which weexplained the key benefits of the A100-Lturbochargers, how they save fuel and how they offer the flexibility NOLwere looking for. The management teamshowed strong interest in the solution wewere offering and after extensive investi-gations decided to go with ABB turbo -chargers. The South Korean yard thatwas to build the ships was asked to sub-mit a quotation based on our solution.”

No is not an answerNow came the next twist in the plot:

The yard indicated that the extra cost ofthe ABB solution was too high. “I wasshocked,” says Arie, “my first reaction was‘it’s over’.” He also remembers that hecouldn’t get the matter out of his head.But he came back, his entire team wasactivated. The effort to win the order wasto take place on three fronts, addressingthe yard, the owner and the engine builder.

Perfect presentFinally an eagerly awaited call just

before Christmas: “ABB has the order,you can pop the champagne corks.”However, there is still one more thing todo. HHI still has to be convinced to fit thefour remaining engines with the A190-Lturbochargers. “This project has a very

high value for us,” recalls Arie Smits. “Notonly have we generated an excellent ref-erence with a major shipowner, but we’vealso ensured that we continue our goodrelations with all parties involved in it. Ontop of this, we’ve strengthened the fuel-saving reputation of our new-generationA100-L turbochargers.”

Arie Smits activated his whole team to win the NOL order.

The NOL fleet comprises 147 ships. Seen here is the APL Korea, a 5108 TEU container ship from itsAPL subsidiary.

“On top of this, we’vestrengthened the fuel-saving reputation of ournew-generation A100-Lturbochargers.”

“An excellent international team, involving about tenpeople, made it possible.”

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Applications

The value of teamworkSo, what were the decisive factors in

ABB winning this important order? Arie isquick to reply: “Having the right productis paramount. With the A190-L the cus-tomer benefits from lowest possible fuelconsumption at all engine load levels,whether we’re talking de-rated or full rated. In spite of the initially higher cost,we offered by far the best cost-optimizedsolution.”

“However, even when you offer thebest solution in the marketplace, there isanother important factor that comes intoplay in a successful project of this kind,and that is teamwork,” Arie says. “I haveto say it is not my success alone. Anexcellent international team, in this caseinvolving about ten people, made it pos-sible. What this story tells us is that witha dedicated team you can achieve any-thing, even when the prospects lookanything but good at the beginning.”

Slow steaming and the A100-L

The success scored by Arie Smits andhis team in Baden and Singapore atNOL involves the “slow steaming” shipoperating mode. The recent economicdownturn started ship owners savingfuel by reducing vessel speeds. Butmarine propulsion engines are set up torun at a specified standard cruisingspeed.

Hence, simply reducing the output ofan engine optimized for higher powersaves fuel but even more can be savedby re-optimizing the engine. The workand expense involved depends on thecharacteristics of the turbocharger tur-bine and compressor. The measure ofturbocharger performance is the “com-pressor map”. It reflects how effectivelyand flexibly engine exhaust gas energycan be converted into compressed air.

A compressor map can be adjustedin several ways. For example: using turbochargers with variable turbine geo-metry (VTG): using an exhaust waste-gate or bypass; exchanging compo-nents like nozzle rings and diffusers.

The measures change the pressureof the exhaust gases reaching the tur-bine and thus the speed it drives thecompressor. NOL’s desire for dual ratings for normal cruising and slowsteaming posed the challenge of con-verting the turbocharging system with the minimum modifications and inminimum time. Thankfully, ABB Turbo-charging’s new A100-L turbochargersfeature the widest compressor mapsavailable anywhere and it was possibleto set the desired turbocharger andengine performance not by modifyingthe turbo-chargers themselves but bymodifying the number of turbochargers.

The ABB Turbocharging systemwhich won the day comprises fourA190-L turbochargers, of which onecan be cut-off from the exhaust gasstream using a valve or simple blankingplate. Despite the re duced level of ener-gy in the exhaust gases at the lowerengine power, the A190-L’s wide com-pressor maps mean the three turbo -chargers still efficiently produce thecharge air characteristics needed.

Active on all fronts, Arie Smits and his team convinced shipyard, ship owner and engine builder.

Exhaust gas receiver

Compressor Turbine

Bypass

valve

TC cut out

Schematic of the flexible A190-L dual rating configuration.

18 ABB charge! 1|11

Operating safety

A testing time – the classificationsocieties in Baden What do an 18th Century London coffee house and our Mönchtest stand have in common?

Text Jonathan Walker, Photography Alex Spichale

ABB charge! 1|11 19

Operating safety

Representatives from Lloyd’s Register (LR), Germanischer Lloyd (GL), American Bureau ofShipping (ABS), Bureau Veritas (BV), RegistroItaliano Navale (RINa), Russian Register (RS),Polish Register (PRS), Nippon Kaiji Kyokai (NK),Korean Register (KR), Det Norske Veritas (DNV)and China Classification Society (CCS) and theJapanese Government Ministry for Land, Infra-structure and Transport (JG/MLIT) witnessedthe Power2 Type Test run.

When we think of how regu-lations can affect productdevelopment, emissionslegislation will spring to

mind. This is understandable: limits onemissions from combustion engines im -posed by bodies like the InternationalMaritime Organisation, the World Bankand national and supranational govern-ments and administrations are highlytopical and have completely changed thethrust of engine R&D in the last 20 years.

But emissions legislation is only arecent example of how something otherthan increasing our customer’s produc-tivity and profitability can influence ourdesign priorities. Indeed, ABB Turbo -charging was recently closely involvedwith an influence on product design thatdates back around 250 years.

Power2 Type Test On 3rd and 4th March this year, we

invited the “classification societies” tothe Baden Test Center to perform a func-tion indispensable to our products reach-ing our customers in our marine markets.

Representatives from 12 classificationsocieties and a government agencycame to witness a so called “Type Test”on a Power2 two stage turbochargingsystem. The object of the exercise wasto demonstrate to the representativesthat our Power2 technology is funda-mentally sound. The process is one thatevery new ABB turbocharger – or turbo -charging system in the case of Power2 –has to complete. It is among the first ofseveral steps demanded by the classifi-cation societies before a new turbo -charger type can be released for every-day commercial use on ships’ engines.The final stage of this turbocharger test-ing process is, logically, when the engineand all its systems is, in its turn, subjectto its Type Test.

In a prescribed procedure, testingbegan on the “Mönch” hot gas test rigwith both the high and low pressure turbochargers of the system powered upfor one hour at their maximum operatingspeeds and maximum operating temper-ature. They were then dismantled forinspection so that the classification so-ciety surveyors and inspectors could sat-isfy themselves that no damage hadoccurred during the test.

Business and coffeeSo how do the classification societies –

as non governmental organizations –come to have this vital role as thearbiters of marine safety and reliabilitywith so much influence over whether ourproducts are considered fit for purpose?

The answer lies in the name of one ofthe organizations present in Baden andwhich can claim to be the first classifica-tion society – Lloyd’s Register of Shipping(LRS) founded in 1740. While always sep-arate entities, LRS shares its name and itsroots with Lloyd’s of London, the famousinsurance and re-insurance market.

And there lies the source of the classi-fication societies’ influence – their will-ingness to classify a ship or approve itsequipment is the principal preconditionimposed by an insurer on the ship’s owneror operator for covering the vessel andits equipment against loss or damage.

Among the classification society rep-resentatives present at the Power2 Type

20 ABB charge! 1|11

Operating safety

Test was Dipl. Ing. Michael Graw, Lloyd’sRegister’s Senior Surveyor resident inSwitzerland. During a break in the typetest program he gave an intriguinginsight into his employer’s origins inwhich the 18th Century English business-man’s love of coffee played a central role.

“Like Lloyd’s of London, Lloyd’s Reg-ister is named after a famous 18th centuryLondon coffee house. In those days, coffee was as popular as beer and coffeehouses were on the one hand not alwaysconsidered reputable. On the other theywere frequently meeting places for busi-ness people and often where they madetheir deals. Edward Lloyd’s establish-ment in London’s Tower Street became aplace where merchants, shipowners,captains and others associated withshipping met daily. To keep his clientshappy, he helped them share informationby printing a sheet of all the news heheard – the equally famous “Lloyd’s List.”

Signing on the line The making of insurance deals was

called underwriting, since the partiesadded their signatures at the bottom ofan agreement. “Their signature commit-ted them to carry a portion of the lossesif a ship was lost,” Graw continues. “Inreturn, they received a portion of the profits if it delivered its cargo safely. Atthis time there were only sailing shipsand transport by sea was hazardous tovery hazardous, depending on the ves-sels’ condition, the winds, the weatherand sometimes pirates.

Of course, without some knowledgeof the ship carrying the insured cargo,this type of arrangement favored themerchant – it was not unknown for un -scrupulous business men to send outoverinsured cargoes in overloaded andunseaworthy vessels with the expresspurpose of profiting from a sinking, withabsolutely no regard for the lives of thecrews.”

The underwriters soon felt the need toknow and classify the condition of theships that they were being asked toinsure. Thus, in 1760, the “Register Soci-ety” was founded to formalize the previ-ously ad hoc arrangements. It becamethe forerunner of what we now know asLloyd’s Register of Shipping.

Classification to type approval Over the next 50 years, steam power

began to supplement and replace sail. “It was then a natural step for the classi-fication societies to create rules for thesafety of machinery on ships,” Grawnotes. “Here was suddenly a major newsource of potential and – all too often –actual danger aboard ships which werestill made of wood,” Graw relates. “Asteam engine relies on a roaring coal fireto create steam at high pressures. Thereis consequently the risk of fire, theescape of scalding steam and water andmany very hot surfaces. To minimize thedangers represented by steam power,boilers, cylinders, seals, shafts andgears, etc. had to be passed as safe bythe classification societies.

In this way the role of the classifica-tion societies evolved from ranking theseaworthiness of the ship itself to settingsafety and reliability standards for theincreasing amount of potentially haz-ardous machinery aboard. So, essentially,we can trace a continuous line fromensuring the safety of the first steam-ships to what we did today in Baden.And going back to the very beginning,from a coffee house in London to theMönch test stand,” Graw concludes.

The test rig for type testing of ABB Turbocharging’s Power2 two stage turbocharging technology atthe company test center in Baden, Switzerland.

The classification societies have a vital role as the arbiters of marine safety.

ABB charge! 1|11 21

Operating safety

“We can trace a continuous timeline from a coffee house in London to what we did today.” Michael Graw, Lloyd’s Register of Shipping with ABB’s Stefan Höner at the Power2 Type Test.

The Register Societybecame the first classifi-cation society and in1764 it printed its firstannual Register of Ships.

Another great influence for safety at sea

L R

540 mm Aft

LT

LTF

LF TF

Deck line

F

WNA

T

S

W

LS

LW

LWNA

All lines are 25 mm in thickness

540 mmForward

230 mm

300 mm

450 mm

230 mm

230 mm

230 mm

Complementing the improvementsin marine safety brought about byLloyd’s Register were the efforts ofEnglish social reforming politicianSamuel Plimsoll (1824 to 1898).

In Plimsoll’s opinion: “The ability of shipowners to insure themselvesagainst the risks they take not onlywith their property, but with otherpeoples’ lives, is itself the greatestthreat to the safe operation of ships.”

Appalled by the activities ofunscrupulous ship owners who sentto sea heavily insured, unseaworthyand overloaded “coffin ships”, hecampaigned tirelessly to ensure thesafe loading of vessels.

As a result of his agitations theMerchant Shipping Act was passed in1876 which gave extensive inspectionrights to the UK Government’s Boardof Trade agency.

The act prescribed the adoption ofthe “Plimsoll line” on British flaggedships. Still used today, this markingon a vessel hull indicates clearly howdeep a fully laden ship is allowed tosit in the water. It takes account of the

varying density of warm and cold seasand varying salt content. For example,the mark includes separate loadinglines for the Atlantic and the lesssaline Baltic.

A memorial to Plimsoll, “The Sailor’sFriend”, stands on the Victoria Embank-ment in London.

Example of a Plimsoll line ship loading gauge.“LR” at the centre shows that the levels werecalculated by Lloyds Register

22 ABB charge! 1|11

Technology

“We used to be do-it-yourself inventors”The luxury yachts of Russian millionaires and North Americanlocomotives have them: exhaust gas cleaning systems from Hug Engineering. All around the globe they ensure clean air. The success story of the Hug Brothers from the small Swiss village of Elsau.

Text Tiziana Ossola Auf der Maur, Photography iStockphoto (p. 22), Michael Reinhard (p. 24), Hug Engineering (p. 25)

Hug Engineering equips everything from power stations to luxury yachts with exhaust aftertreatment.

ABB charge! 1|11 23

Technology

Pointing to a photo of a luxurypleasure craft worth a billionSwiss Francs, Thomas Hugnotes: “We have just equipped

the new yacht of an Arabian Sultan withexhaust gas aftertreatment.” The founderof Hug Engineering and today Chairmanof the Executive Board goes on to makethe scale of things clear. “The yacht consumes as much electrical power as a town of 15,000 inhabitants – withoutcounting its propulsion power!” For theSwiss exhaust gas treatment specialistthis contract is nothing out of the ordinary. Aside from a few small adapta-tions, the filter system comes straightout of the company’s standard productrange.

Simple but not commonplace“We clean exhaust gases” is the claim

of the company from Elsau, a small vil-lage not far from Winterthur in Switzer-land. The message is clear but not trivial.Whether stationary engines in electricalpower plants, mobile and marine installa-tions on locomotives or ships, on dieselengines, gas engines or in waste inciner-ators, Hug’s mission is to reduce harmfulexhaust emissions.

Hug exhaust gas cleaning productsare their own inventions. Materials, keycomponents, process technologies: inits 28 years the company has designedthem, tested them, perfected them anddeveloped them to production readiness.The technique of using urea to convertnoxious substances – oxides of nitro-gen – into benign nitrogen and watervapor, called selective catalytic reduction,or “SCR”, proved to be trailblazing.

Market gardeners achieve around 30 % greater yields thanks to CO2 enriched air technology. “We find that satisfying,” says Michael Hug.

24 ABB charge! 1|11

Technology

Specialists in exhaust gas cleaning: Brothers Christoph, Michael and Thomas Hug (left to right).

In the so-called heavy duty enginesector in particular – i. e. locomotives,ships, large stationary installations run-ning on problematical fuels – it is not justa case of efficiently converting oxides ofnitrogen, unburnt hydrocarbons, carbonmonoxide and soot particles into some-thing harmless. Restricted space aroundthe engine, durability in the face of largetemperature fluctuations and shock load-ing, longevity, ease-of-maintenance andexhaust silencing are further factors thatan exhaust gas aftertreatment system hasto cope with as a matter of course. Themajority of production takes place in-house, from start to finish. Even some ofthe manufacturing equipment that auto-mates the production processes wasinvented and built by Hug.

The three brothers “We were a jobbing workshop”, is how

Thomas Hug describes the company’shumble beginnings, not without a hint ofunderstatement. “We” means Thomasand his brothers Christoph and MichaelHug. They are the heart and soul of thecompany. All three are engineers. Techni-cal thinking runs in the family. Their fatherwas an engineer. The sense of solidarity

among the brothers was always strongand over the years has proved a firmbasis for the shared management of thecompany. Thomas, the eldest, is Chair-man of the Executive Board, Michael, theyoungest, is CEO. Christoph is Head ofResearch & Development.

In addition, all three are passionatemodel aircraft builders. “Aircraft construc-tors are distinguished by two characteris-tics: creativity and innovation,” notesMichael Hug: “This is exactly what weneed in our business, too.” It is not merechance that many an engineer in thecompany is also a model aircraft builder.

A political tail wind. Hug has always found solutions. In

1988 the three man company won its first contract, from the ElektrizitätswerkSchaffhausen. The electrical power pro-ducer ordered an exhaust aftertreatment

system for a diesel power station. At thattime exhaust gas cleaning for combustionengines was practically non-existent andsome things were classed as impossible.Cleaning diesel exhaust gases was notconsidered feasible, Thomas Hug recalls.“Our customer believed in us and thatwas the best thing that could have hap-pened to us,” he notes looking back. Theengineers’ pioneering spirit was ignited.They succeeded in building the equip-ment.

The necessary basic research wasnot just there to be accessed. The HugBrothers took matters into their ownhands. They built their own research laboratory and acquired the necessaryexpertise regarding materials andprocesses. Today this lab is still thesource of the precise and reliable data onwhich the further development of Hugexhaust gas cleaning products is based.

Materials, key components, process technologies: in its 28 years the company has designed them,tested them, perfected them and developed them to production readiness.

ABB charge! 1|11 25

Technology

From research to production – a ceramics engineer in the Hug labs.

Setting of the filter substrate material afterextrusion.

Cutting to length of the silicon carbide “honeycomb” cores.

Over many years the company hasgathered a fund of know-how in the fieldof pollution reduction which is unrivaled,even on a world scale. Only a few playershave been in the market as long as HugEngineering. Today, their exhaust gascleaning systems carry the most strin-gent international certifications.

Assistance came from the world ofpolitics. Hug started up at a time whenthe concept of environmental protectionwas gaining ground on political agenda.The company was always abreast of everstricter clean air regulations, both nation-al and international. “Environmental leg-islation is certainly one of the engines ofour growth,” Thomas Hug confirms.

Of success and approbation The company grew continuously and

rapidly even beyond Switzerland’s bor-ders. Between 2003 and 2008 salesgrew fivefold. The principal markets areno longer just Switzerland but all West-ern Europe, North America and SouthEast Asia. A massive 95 % of productionis exported and to countries where “envi-ronmental legislation is not only strict butalso enforced,” as Thomas Hug puts it.

Market success cannot, however, beequated with universal approbation,observes CEO Michael Hug. “Our cus-tomers are not always filled with joy. Theyhave to buy our products to comply withthe law,” Thomas Hug says, taking up thepoint. “The added value is environmentalprotection which does not directly bene-fit our customers’ balance sheets.”

But there are other examples. In the1990s the company invented a processfor feeding carbon dioxide into green-houses to accelerate growth. It is used inthe cultivation of flowers and vegetablesin market gardens (see charge! 1 /10).

The revolutionary aspect was that thesystem uses the CO2 from the exhaust ofa gas engine to fertilize the plants. Forthis it is necessary to transform the gasengine’s emissions into breathable air.This is technically very complex. “The airhas to be even cleaner than normalambient air because flowers and vegeta-bles are more sensitive to impurities inthe air than humans,” Michael Hugstresses.

With this technology the growersachieve increases in yields of around30 %. And the customer does not haveto buy bottled CO2. It comes from theengines and is worth more than the natural gas that the engines burn. “Theadded value is enough to amortize theinstallation. We find that satisfying,”notes Michael Hug, summing up.

This success story brought severalimitators onto the scene, but the companyfrom Elsau is still the global marketleader with 70 to 80 percent marketshare. There are 1500 such installationsoperating worldwide, in The Nether-lands, the USA, Canada, Poland, Russiaand, in the near future, New Zealand aswell.

Threshold countries also offer inter-esting perspectives for the exhaust gasspecialist. “Several have enacted envi-ronmental laws, but that alone is notenough,” notes Thomas Hug. “In our

experience it takes about five years for legislation to be fully enforced.” In themedium term, China and India will alsobe on the agenda. As a medium sizedcompany Hug Engineering is reaching itslimits and is considering various strate-gies. A conceivable course is to joinforces with an industrial partner.

New answers Even after 28 years, pioneering spirit

is still in demand. This is demonstratedby Hug’s cooperation with ABB Turbo-charging. So far no exhaust gas treat-ment system exists for engines using thePower2 two stage turbocharging system(see separate text). Both companies areworking intensively on a solution. “Twostage turbocharging presents the oppor-tunity to make exhaust aftertreatmentmuch more elegant,” Thomas Hugexplains. The exhaust cleaning systemcan be inserted between the two turbo -chargers. “That brings a major customerbenefit,” observes Thomas Hug. “Thewhole system becomes more compactand less expensive.” Technically a lot ofwork is involved, however. Even after 20years, inventiveness is still a sought aftercommodity.

CEO Michael Hug: advancing by innovation was always our company’sstrength and that’s how it will stay.”

In early April 2011 Hug Engineering signed a contractcalling for the takeover of 2⁄3 of the company sharesby German automotive systems and component supplier ElringKlinger AG. However, the companyremains under the existing management.

26 ABB charge! 1|11

Technology

ABB Turbocharging and Hug Engineering developInnovative SCR System Text Sven Johannsen, Business Development & Cooperations ABB Turbo Systems, Project Manager, Photography Alex Spichale

How do you combine Power2 two stage turbocharging and aftertreatment? The ABB Turbocharging project team: manager Sven Johannsen with Jürg Weber, Philipp Schürmann, Carsten Lipfert, Mihajlo Bothien (left to right).

ABB charge! 1|11 27

Technology

The regulatory challengeCurrently, builders of medium speed

engines are looking for ways of achievingupcoming restrictions on emissions ofoxides of nitrogen (NOx ) such as IMOMarpol for ships and World Bank regula-tions for land based diesel power plants.Among other things, the cost and bene-fits of exhaust gas recirculation (EGR),gas fueling, water or steam injection,variable valve timing and Selective Cat-alytic Reduction (SCR) are being investi-gated. The time will tell which technology or combination of technologies will beadopted. From our point of view, thereseems to be a consensus among enginebuilders that SCR will be the fallbacksolution if other concepts fail to demon-strate their benefits.

SCR – a proven achieverThis confidence in SCR as a last

resort if all else fails stems from its longtrack record and its status as a “panaceatechnology”, i. e. its potential to clean upvirtually any engine due to its high NOx

reduction rates. SCR technology was first introduced

in the 1980s for thermal power plants.Subsequently, it was adapted to largediesel engines, with our partner HugEngineering playing a pioneering role.Today, a large number of ships and

diesel power plants running on all kindsof fuels are equipped with SCR. Some ofthem have been running for more than20 years and achieving NOx reductionrates of up to 98 %.

How it works, where it worksIn the SCR process, a source of the

reducing agent ammonia (NH3) is intro-duced into the exhaust gases in the pres-ence of a catalyst. Due to its relative easeof handling, a common source of ammo-nia for this purpose is an aqueous (water)urea solution – known in European truck-ing circles as “AdBlu®”. In the SCR cata-lyst the ammonia reacts with the NOx

(nitrous oxide NO and nitrogen dioxideNO2) in the exhaust gases to form nitro-gen and water vapor, both constituentsof clean air. The desired reaction takesplace in a temperature window between250 °C and 550 °C, but for the fuel quali-ties typically used in medium speedengines today, this temperature windowis narrowed down to 300 °C to 500 °C toavoid catalyst contamination and unde-sired side re actions. In today’s mediumand high speed engines, these tempera-ture windows nicely match the prevailingexhaust gas temperature.

Can Power2 and SCR becomefriends?

Compared to a conventional single-stage turbocharger, ABB Turbocharg-ing’s Power2 two stage turbochargingsystems extract more thermal energyfrom the exhaust gases before returningit to the engine’s combustion process.As a result, the exhaust gas temperatureafter the turbochargers is too low foroptimal SCR operation at some or evenall engine loads, depending on applica-tion circumstances. At first glance, thisonly adds to the dilemma of achievinghigh engine efficiency and low NOx emis-sion values.

Good News But now the good news: the exhaust

gas temperature between the turbo -chargers of Power2 is reliably in therange SCR needs! Of course, a set-up isrequired where the SCR unit is connectedbetween the high-pressure turbine outletand the low pressure turbine inlet, whichpresents challenges. If a conventional sizeSCR reactor is used, next to the enginethere would be a box about half its size aswell as several meters of piping.

But there is more good news: Theexhaust gases between the turbocharg-ers is in a state of higher pressure anddensity than further downstream in theexhaust system where conventional SCRsystems are located. These gas condi-tions between the turbochargers makethe SCR reaction even more efficient –consider the analogy of a pressure cookerwhere higher pressure and temperaturehelp you cook potatoes faster. This allowsa much smaller catalyst volume to beused to convert the same amount ofNOx into clean air.

Minimize for maximum benefitIn sum, the SCR reactor needs to be

installed between the turbochargers butcan become considerably smaller. Thisgave rise to the idea of mounting theSCR reactor unit onto the engine, in-stead of placing it somewhere in theexhaust stack or engine room. ABB andHug’s engineers are now endeavoring tointegrate the SCR unit into the turbo-charging system, an even more demand-ing challenge. But we feel this effort isworthwhile because an integrated on-engine arrangement of the SCR systempromises several benefits to ABB’s cus-tomers – engine builders and operatorsalike (see boxed text).

Benefits

– A downsized, compact system will reduce the first and operatingcosts of the exhaust gas after-treatment system

– The on-engine arrangement will reduce the space required by theexhaust gas treatment system.This would especially benefitmobile applications, such as shipsand locomotives, where any spacesavings will increase cargo capacity.

– An integrated, on-engine arrange-ment will simplify the certificationprocess, as the exhaust gas treat-ment system can be tested andcertified together with the engineas an integrated unit. Costly on-site commissioning and certifica-tion could be avoided.

– Combining the turbocharger sys-tem and SCR will allow one-stopservicing for both systems; withABB Turbocharging’s global servicenetwork, operators worldwide canrely on the same service availabilityas for their ABB turbochargers.

The exhaust gas temperature betweenthe turbochargers ofPower2 is reliably in therange SCR needs!

28 ABB charge! 1|11

News

People

Dirk Wunderwald On 1st July 2011 Dirk Wunderwaldwill take over the management of thenew turbocharger business at TurboSystems United Co., Ltd. (TSU), ABB Turbocharging’s Joint Venture in Kobe, Japan.

Gerald MüllerDirk’s successor as manager of thehigh speed segment will be GeraldMüller, who returns to the companyafter periods at two other organiza-tions.

And BasakIn Istanbul, Turkey, And Basak, has taken over as manager of theABB Turbocharging LBU. And waspreviously Business DevelopmentManager and from 2007 to 2009LBU Manager in Azerbaijan.

Miramar holds Emissions CIAC CIAC. On 2nd March, 2011, our LBU inMiramar Florida /USA took an importantinitiative. Anticipating the 1st August dec-laration of most of the coasts of USA and Canada Coasts Emissions ControlAreas, Miramar staged a Customer Infor-mation and Awareness Course on thepractical aspects of IMO emissions legis-lation. Much appreciated by its guests,the CIAC included presentations fromRobert Kaidy of the Society of NavalArchitects and Marine Engineers, ChiefInspector Paul Bates of the US Coast-guard and Ravi Mehta of Det Norke Veritas classification society.

Claire Carmona and Andreas Biller of GE sign aturbocharger servicing agreement.

China LBU of the year 2010Award. The ABB Local Business UnitTurbo charging consisting of the Jiangjinturbo charger works of ABB Jiangjin TurboSystems Co., Ltd and six Service Sta-tions has won the first annual award forthe “Best Performing LBU of the Year2010”. One of the criteria was the suc-cessful implementation of several keyperformance indicators introduced at thebeginning of 2010. In China’s case thisincluded “Increase service revenues withinactive /new customers”. The award wasreceived by ABB Jiangjin Turbo SystemsCo., Ltd President Ulrich O. Birch onbehalf of ABB Turbocharging China fromOliver Riemenschneider, Senior Vicepresident Sales, Marketing and Serviceat the ABB Turbocharging global busi-ness unit in Baden.

OPAC success inSpain and PortugalOPAC. On 15th March, 2011, Claire Carmona, manager of the ABB Turbo -charging LBU in Madrid and AndreasBiller, Manager of Motor Services forSpain and Portugal at GE Jenbachersigned an OPAC Operation PerformancePackage. The OPAC delegates to ABBservice of turbochargers installed on GEJenbacher gas engines in cogenerationplants in Spain and Portugal for 8 years.With the agreement, GE Jenbacher hassubcontracted turbocharger repair, main-tenance and overhaul from its ownagreement to service complete enginesinstalled in plants around the two coun-tries. The turbocharger service work willbe carried out at our Service Stations inAlgeciras, Madrid and Barcelona. Handover of the LBU of the Year award.

ABB staff and visitors at the Emissions CIAC.

ABB charge! 1|11 29

Service

The confusing case of thecounterfeit compressor ABB Turbocharging puts non-original parts under the magnifying glass and finds incriminating clues. (With apologies to Sir Arthur Conan Doyle.) Text Jonathan Walker, Photography Michael Reinhard

René Stoverink looks for tell-tale clues on a non-original compressor wheel.

30 ABB charge! 1|11

Service

Aglobal population of more than190,000 ABB turbochargerson engines which can be inoperation for up to 30 years

represents a huge potential for mainte-nance, repair and overhaul. And anenticing target for ABB Turbocharging’scompetitors in the service market.

Unfortunately, ABB turbochargers inthe field are a target for companies notonly wishing to carry out the physical workof turbocharger service but also wantingto profit from demand for spare parts.

“There is a ‘gray market’ for turbo -charger parts copied from our originals,”explains René Stoverink of ABB Turbo -charging’s technical service department.“But the properties of these non-originalsnever measure up to the ABB Turbo-charging original parts and are the sourceof problems. The attraction of copyingparts is their price – the copier leaves theinvestment in the research and develop-ment of the technology behind the partto ABB Turbocharging.”

In fact there has never been an easiertime to replicate an original. “Laser meas-uring equipment can be used to scan acomponent contactlessly and record itsdimensions,” Stoverink points out. “Butas we have seen in a recent investiga-tion, there is still a wide gap betweenknowing a part’s dimensions and makingit accurately.”

Non-original parts become a problemwhen ABB Turbocharging’s service depart-ment is asked to service or repair a

turbocharger that contains such parts.“How can ABB Turbocharging give itscustomary warranty when it cannot know the provenance and quality of the turbocharger’s existing components?”Stoverink points out. “The most seriouscase of all is, of course, when the turbo-charger fails, causing the engine to fail,and the customer is looking for some formof redress, not only for the turbochargerrepair but for consequential losses.”

However, proving that non-originalparts have been used is becoming moreand more difficult as copiers becomemore daring. “The most audaciousattempt to not only copy the part but alsothe markings which identify it as an ABB original,” Stoverink notes. “This is to intentionally confuse and mislead thecustomer and may infringe ABB Turbo -charging intellectual property.”

Detecting defects Identifying such parts may not be

straightforward. It has to be completelyremoved from the turbocharger and allits surfaces carefully inspected. Often amagnifying glass is required to look forclues. “This and the intentions of somecopiers to mislead and infringe other’srights makes the whole process reminis-cent of detective work à la SherlockHolmes,” Stoverink jokes.

In fact, the comparison with detectivework is not far fetched at all. Whilereplacing a non-original part with an orig-inal ABB Turbocharging part will not usu-

ally prevent a serious felony, it can pre-vent a great deal of financial loss, both interms of repairs and engine fuel con-sumption.

A copied compressor wheel for anABB Turbocharging TPL turbochargerrecently came into Stoverink’s handsand, aside from the lack of an ABB logo,it was very difficult to distinguish the partfrom an original at first sight. “The onlyobvious clue was rather inconsistentmachining patterns on the compressorvanes. Where ours have smooth curvedprofile, the non-original part’s were madeup of series of curves.”

ElementaryIt was decided to put the compressor

wheel through a rigorous set of tests,and the methods used would have notbeen out of place in a Sherlock Holmesshort story. As well as using pure logicand deduction, Arthur Conan Doyledepicted his consulting detective as apolymath with a deep knowledge ofphysics and, especially, chemistry.“Holmes would have approved of themethods we used,” Stoverink notes in alighter moment. “We inspected the partunder a microscope; took very precisedimensional measurements; and sentsamples of its material (forged aluminum)for metallurgical analysis, to be able tocompare its chemical composition withour own material specifications.”

The microscopic inspection andmaterial analysis aim to determine the

The non original compressor wheel was precisely measured to establish its geometric accuracy.

To prove that copy partshave been used isbecoming more andmore difficult as copiersbecome more daring.

ABB charge! 1|11 31

Service

compressor wheel’s strength and hencefitness for service and life expectancy.“Deficiencies like weak, low grade mate-rial and cracking could lead to disinte-gration of the component. If similar deficiencies were present in the turbo -charger casings, then we could haveserious problems with the containmentof rotor fragments during an overspeedincident.”

The microscopic inspection estab-lishes the surface condition of the part.“This is important in terms of aerody-namics,” Stoverink stresses. “Rough sur-faces cause turbulences, reducing turbo-charging efficiency.”

Forgings or forgeries? What neither the visual inspection nor

the material analysis could show were,the production processes involved inmaking the copy. “The strength of an alu-

minum compressor wheel derives to agreat extent from the way its material isforged and heat treated,” Stoverinkasserts. “We know only a handful of alu-minum forges worldwide capable ofmeeting our strict specifications. Theyuse very precisely calculated forgingforces and heat treatment. They do notsupply copiers!”

In the air forceAerodynamic efficiency is also an

aspect which dimensional measure-ments can elucidate. “The effectivenessof the compressor wheel at sucking in airand compressing depends to a greatextent on the aerodynamic efficiency ofthe vanes we design at great cost andwhich the gray market tries to emulate.We have seldom seen non-original partsthat come even close to the efficiencieswe achieve.”

Another aspect of compressor vaneshape is vibrational behavior, whichchanges considerably with the distribu-tion of the mass of material along thevanes’ cross section. “We design our

compressor wheels very carefully in thisrespect. We aim to ensure that duringoperation the vanes avoid resonance fre-quencies when the source of the vibra-tions – in this case pressure waves andthe rotation of the rotor – coincide withthe “natural”, or “resonance” frequencyunique to the shape and material of thevanes. At these frequencies a great dealof energy is absorbed by the material,causing them to bend, flex and twist. Ifthis continues for too long, fracture ofthe vanes due to so-called high cyclefatigue (HCF) can result.

Dimensional deduction True to form, the dimensional inspec-

tion of the gray market compressor wheelon ABB Turbocharging’s extremely accu-rate three dimensional equipment atBaden revealed deficiencies in all the areasdescribed. “The reasons are clear: we

have the original drawings and the machinetools are correctly programmed to accu-rately produce the shapes we design.”

The main areas of dimensional exami-nation of the copied compressor wheelwere blade geometry, the accuracy of itscentral bore, which determines its con-centricity on the turbine shaft, and its bal-ance condition. “Deviations in the bladesfrom our drawings were considerableand would have a significant impact onboth their aerodynamics and vibrations,”notes Stoverink. “Simulations with thedesign of the non-original compressorwheel showed that the natural frequen-cies of the blades are in a significantlylower range than those of a compressorwheel from ABB Turbocharging’s pro-duction. They would fall within a rangecapable of being excited by the runningturbocharger and run a high risk of bladefailures due to HCF.”

A case of equilibriumTurning to centering of the compres-

sor wheel on the turbine shaft seat, themating surfaces of its seat were out of

tolerance, as was the roundness of thebore. “The resulting misalignment of thecompressor wheel on the turbine shaftmeans both that the mounting of thecompressor wheel is not fully repeatableand that imbalance will occur in therotating shaft,” Stoverink emphasizes.“Indeed, the compressor wheel showsnone of the tell-tale grinding marks thatevidence balancing after production. Atall ABB Turbocharging works, every com-pressor wheel destined for use as aspare part is very finely balanced, since itmay be used in an in situ repair on a shipor in a power station where there is nopossibility to rebalance the completerotor. In this way, we know that therepaired turbocharger will be in the bestpossible state of balance.”

Finally, aside from vibrational effects,the geometrical deviations of the non-original part could have severe negativeeffects on the aerodynamic efficiency ofthe compressor wheel.

One per cent or 50,000 dollars“While deficits in vibrational behavior

are more relevant to avoiding turbo -charger damage, poor aerodynamic effi-ciency soon translates into reducedengine efficiency,” Stoverink continues. “1 % is soon lost due to poor dimensionaltolerances and the loss can be repeatedon the exhaust gas side of the turbo -charger when a copied, out of toleranceturbine wheel or turbine casing is alsoused.”

Putting a figure to the loss to theengine end user, an engine builder hasindicated that a 1 % reduction in tur-bocharger efficiency translates into areduction of over 1⁄3 gram per kilowatthour (g /kWh) specific fuel consumption.“A medium sized low-speed engine rated50 MW, as used in many container ships,with a turbocharger 1 % below its designefficiency would use more than 100 tonsof extra fuel in a 6000 hour operatingyear. This means up to 50,000 US dollarsat a fuel price of 500 USD per ton.

Our case rests.

Every compressor wheel destined for use as a spare part is very finely balanced, since it may beused in an in situ repair on a ship or in a power station where there is no possibility to rebalance the complete rotor.

32 ABB charge! 1|11

Applications

Gas engines setsail out of their100 year niche Large gas engines have long lived in the shadow of large dieselengines. Rolls-Royce and others are changing this.

Text Jonathan Walker, Photography Rolls-Royce

And ABB Turbocharging, withPower2 two stage turbo -charging playing a leading rolein bringing gas engines out of

the niche markets they have occupiedsince their invention in the 19th century.

That gas engines played second fid-dle was demonstrated clearly on the veryday in 1897 that Rudolf Diesel presentedhis engine to the world. Although NicolausAugust Otto had produced gas engineson an industrial scale at his works inDeutz, Cologne, since 1869, and althoughDiesel was using Otto’s 4-stroke cycle onhis engine, the market communicationfocus was the new engine’s 24 % effi-ciency. Four times higher than the lateststeam engines, but only narrowly betterthan the 20 – 22 % Otto’s spark ignited(SI) gas engines attained.

In fact, the reason for Diesel’s empha-sis was that gas was only transportablevia a fixed infrastructure (pipes) and hewas looking at all applications: mobile,stationary and marine.

Little changed for around 100 years.One of the earliest uses of Otto’s gasengines was generating electricity fromtown gas, and today typical modern gasengine applications are burning pipednatural gas to produce electricity andheat in cogeneration plants or taking gasfrom a pipeline to run a compressor.Likewise, the relative efficiency of mod-ern gas engines and diesels is still inabout the same range as in 1897.

New appealHowever, a combination of factors is

expanding gas engine appeal. Crucially,there is a great deal of natural gas in theworld. All forecasts call for massiveincreases in its availability and use as the21st Century progresses. It will reducedependence on fossil liquid fuels and anew gas supply infrastructure is set toemerge.

The problem of transporting gas as afuel, which was solved for cars and trucksabout 30 years ago, has been solved for

ships and vehicles using the same basicstorage technologies. Compressed natu-ral gas (CNG) and liquefied natural gas(LNG) can be produced by compressing itto medium and high pressures, respec-tively. Both can be stored in transportablecylinders, whereby LNG offers far the bet-ter ratio of stored volume to stored mass.

Gas propulsion Equally important, gas engines have

come to the notice of the marine industryfor their environmental advantages. Thesimplest combination of carbon andhydrogen natural gas is essentially cleanburning and modern gas engines buildon this. Using so-called lean burn com-bustion (cylinder charges with highexcesses of air to ensure cool but effi-cient combustion) they create very lowemissions of oxides of nitrogen (NOx )which readily undercut the limits speci-fied by IMO Tier III. This third stage ofmarine engine emissions reduction to beimposed by the International Maritime

ABB charge! 1|11 33

Applications

Built in 2006, M/F Bergensfjord is one of the first ferries powered by SI gas engines. With Rolls-Royce power it can carry 589 passengers at speeds of upto 21 knots.

Organisation after 2016 specifies an 80 %reduction in Emissions Control Areas(ECAs), i. e. coasts near centers of popu-lation and areas of environmental sensitiv-ity. The same also applies to reductions inoxides of sulfur (SOx ) – commercial natu-ral gas is classed not merely as a “low sul-fur fuel” but a “no sulfur fuel”. Gas enginesexhausts are also virtually particle free.

ChoicesMarine engine builders and users

have alternatives. First, there are twokinds of gas engine: the spark ignited (SI)engines pioneered by Otto, and dual-fuel(DF) engines. The dual-fuel engine waspioneered on vessels transporting LNG.The air /gas mixture is ignited not by aspark plug, but using the diesel ignitionprocess, via a 1 % liquid fuel “pilot”. As aback-up, dual-fuel engines are alsoequipped with a full size fuel injectionsystem to allow 100 % diesel fueling.

Second, as well as full gas enginesolutions for ships, there could also be

partial solutions where propulsion isswitched to SI gas engines, or dual-fuelengines from liquid fuel to gaseous fuelwhen entering ECAs. Similarly, a gasengine could deliver the ship’s electricalpower needs when in harbor to reducelocal pollution

Finally, based in part on our efforts,gas engines are becoming more efficient,more powerful and more tractable. In2010, specialist GE Jenbacher launchedthe first SI gas engines equipped withPower2 two stage turbocharging tech-nology from ABB. From the first the newgas engines offered 1 % better efficiency.This may not sound much, but chartingthe development of gas engines will givean idea of how considerable it really is.Equally significant is a 10 % rise in powerdensity, i. e. the power the engine canproduce from a liter of displacement, andimprovements in gas engines’ ability tomaintain power output in adverse ambi-ent conditions (high temperatures orhumidity).

This third stage ofmarine engine emissionsreduction to be imposedby the International Maritime Organisationafter 2016 specifies an80 % reduction in Emis-sions Control Areas.

34 ABB charge! 1|11

Applications

Mr. Miller again The term “Miller Cycle” is familiar to

readers of charge! Briefly, it involvesclosing an engine inlet valve early to pro-mote expansion and hence cooling in theair entering the cylinder. The high turbo -charging pressure ratios produced byPower2 compensate the shorter valveopening time to ensure enough air isavailable to maintain – or improve –engine power output.

On diesel engines the cooling effect isused to prevent the temperature peakswhich cause 90 % of NOx. But thanks tolean burn technology, modern gasengines are intrinsically low NOx prime

movers, so instead the cooling effect isused to alleviate a drawback inherent tothe way gas engines work. Unlike thediesel engine, where fuel is injected intothe combustion air after it has been com-pressed and heated, in gas engines theair and fuel are mixed outside the cylinderand compressed together. As the pistonrises on the engine’s compression stroke,the temperature in the air /gas mixture ris-es and if the rise is excessive, it can leadto premature ignition of the mixture. Thisis called “knocking” due to the noise it makes and can occur because thecalorific value of natural gas in pipelinesmay vary considerably over short periods.

Between a knock and a hard place This is a dangerous condition, since

the mixture explodes as the piston is stillrising under the force of combustion inthe engine’s other cylinders. The pistoncrown and connecting rod bearings arecaught between opposing forces. In this“hammer and anvil” situation, damagecan soon occur. However, with the addi-tional cooling due to the Miller Cycle, thetemperature of the air /gas mixture can bekept further from the “knock boundary”.And can be operated more flexibly interms of settings (e.g. mixture richness,ignition timing).

Power 2 two stage turbocharging alsoallows some of the compression work tobe transferred from the gas engine’s pistons to the turbocharger, resulting inhigher mechanical efficiency as well asincreased cooling of the charge air. Thus,thanks in part to Power2, gas engines arebecoming more powerful and more effi-cient, just as a new field of application isopening up for them.

Pioneered in Norway To get the latest news on the trend to

marine gas engines, charge! interviewedprominent figures from Norway, wheregas engines use for both marine propul-sion and shipboard electrical powergeneration has been growing for over 10 years.

The Scandinavian country is bothhighly environmentally aware and a majoroil and gas producing nation. It thusmade sense to apply gas engines inships, starting with ferries, expanding tothe ships which provide passenger andfreight transport across the fjords alongNorway’s coasts and, in the latest phase,the vessels which service the drilling rigsand production platforms of Norway’soffshore oil and gas industry.

We spoke first to Lars M. Nerheim,Assistant Professor at Bergen UniversityCollege, who is deeply involved in gasengine research and chairman of the gasengine working group at CIMAC. “I thinkdecisive factors will be environmentalacceptance and fuel availability, whileincreases in specific power output will bea useful bonus,” he stated. “Overall, thefuture will be more about complying withever stricter and more comprehensiveemission regulations – we will see sootand PM limits for larger engines as well.”

On gas engines the Miller Cycle is used to increaseoperating flexibility.

Operating principle of a Rolls-Royce spark ignited gas engine. The turbocharger uses a VTG toimprove fast load imposition.

ABB charge! 1|11 35

Applications

A complete SI gas engine propulsion solution, including gas storage cylinders.

Efficiency gap?He quickly pointed out that the diesel

engine’s lead is not so clear-cut. “The gasengine has passed the diesel in some cat-egories. The best medium speed gasengines already have better efficiency witha fraction of the emissions of their dieselbrothers. I expect we will see this in othersizes of engine as well, and two stage turbocharging will also make this situationeven better.

So the ‘gap’ will only exist in terms ofspecific output, and this will tend to loseits significance except in certain specialapplications.

Two stage turbocharging will be uti-lized in different ways in the two engineconcepts. For the gas engine it will bemore important to use it for modifyingthe cycle, i. e. effective compression inthe cylinder as well as for some form ofcharge cooling using the Miller Cycle.”

Regarding the type of gas enginewhich will prevail in marine applications –i. e. SI or dual fuel – he sees the presentdual-fuel preference as a sign of conser-vatism. “Dual-fuel’s advantage is that itprovides ‘back door’ safety in terms offuel flexibility. But dual-fuel engines arecompromises and hence do not take fulladvantage of the benefits of gas fueling.

On the other hand, as gas enginepower gets bigger and bigger there ismore of a challenge to run according tothe pre-mixed homogeneous combus-tion principle than with smaller engines.So, if we simplify and say that thebiggest engines will remain diesel any-way and use exhaust clean-up concepts

like SCR and scrubbers, which they canbetter justify on a cost and space basis,then smaller medium- and high-speedmarine engines will be the arena for gasfueling.”

Of these, Nerheim thinks the SI leanburn engine will become the engine typeof choice. “If dual-fueling is required,then the engine room will be composedof a mixture of dedicated gas and dieselengines according to the operating pro-file the ship is designed for. We can seethis trend in Norway already.”

Nerheim sees the installation of a gassupply infrastructure as somewhat politi-cal. “The latest developments are thatsupranational bodies like the EU havestarted to get interested, initially by sug-gesting that LNG terminals should alsoprovide LNG bunkering facilities.”

Pioneer opinionsWe then turned to one of the recog-

nized pioneers of marine gas engines,Rolls-Royce Marine AS, Engines inBergen, where we spoke to Leif-ArneSkarbø, vice president technology anddevelopment. Beginning his comments,Skarbø noted that the engine builder isworking closely with the classificationsocieties and other authorities to developrules suitable for pure gas marineengines.

Looking at emissions, Skarbø consid-ered that engine emissions profiles canpartly also be evaluated in fuel consump-tion terms. “An engine with emissionsabove the legislated limit will needresources to become compliant, either via

increased fuel consumption, urea con-sumption, or investments like exhaustaftertreatment. A pure gas engine whichcombines high efficiency and IMO Tier IIIcompliance thus has advantages overdiesel engines. In any case, the fuel effi-ciency of the best pure gas engines iseven better than the equivalent diesel andthey need no complex exhaust aftertreat-ment. This is a benefit in reduced invest-ments, zero maintenance and no runningcosts, as in the case of urea injection.

Carbon dioxide emissions are alsolower due to the lower carbon density innatural gas, and prices for gaseous fuelsare forecast to remain favorable. And,the drawback of limited LNG availabilitywill be reduced – stations are spreadingfast in Europe and in the US plans areunderway.”

Looking at fuels. Skarbø saw LNGremaining the fuel of choice, but pointsout that Rolls-Royce gas engines arevery flexible. “LNG is obviously betterthan CNG, but LPG is also fully possible.However, there are serious safety impli-cations due to LPG being heavier thanair and classification approval will be amajor challenge”

In terms of technologies apart fromtwo stage turbocharging capable of nar-rowing the power density and efficiencygap between gas and diesel engines,Skarbø stresses ignition systems. “Higherpower density on gas engines alsodepends on stable and robust ignitionsystems and these form a fundamentalpart of our gas engine development roadmap.”

Thanks to technologieslike Power2, gas enginesare becoming morepowerful and more effi-cient.

Tips for the operator

While cylinder outlet tem-perature is a central valuefrom which an enginebuilder can derive infor-

mation about component material tem-peratures, the quality of combustion andthe power output of the cylinder con-cerned, for the turbocharger manufacturer– and operator – it is the temperaturedirectly ahead of the turbocharger that isa decisive value.

But why should there, essentially, bea difference between these two tempera-tures? After all, only the engine’s usuallywell insulated exhaust pipes lie betweenthe exhaust valve ports of the cylinderhead and the turbocharger’s turbine inlet– and the nearest cylinder is often only afew centimeters from the turbocharger.

Well, there is a difference and this isexplained below. Suffice it to say at thispoint that the difference is considerableand the situation is counter-intuitive:measurements on engines in the fieldhave shown that the exhaust gasesdirectly ahead of the turbocharger canbe 100 – 140 °C above the temperatureindicated by the sensors engine buildersfit at the exhaust ports.

This temperature differential (�T) is animportant reference value for engineoperators. To get the important operat-ing values mentioned above, enginebuilders invariably fit temperature sen-sors at all the cylinders of their engines.By contrast, a temperature sensor is notalways fitted ahead of the turbocharger.

Wet CleaningThis situation can cause difficulties

when the engine operator wishes to car-ry out wet cleaning of the turbocharger’sturbine-side components. This is neces-sary to remove deposits left when theengine is burning fuels like marine diesel(MDO) or, especially, heavy fuel oils(HFO). Such deposits completely changethe carefully designed aerodynamic andthermodynamic behavior of the compo-nents in the exhaust gas path, in particu-lar at the nozzle ring, the turbine and tur-bine housings. In the case of lower qual-ity heavy fuels, these deposits can bevery hard to remove, especially in con-junction with exhaust gas temperaturesof above 520 °C.

The injecton of cold water causes asudden temperature change in the mate-rials of the turbine-side components andin most cases a noticeable rise inexhaust gas temperature. Injecting waterraises the density of the exhaust gasesand at the same time extracts heat fromthe exhaust gases, resulting in reducedenergy reaching the turbine. Both effectscause a decrease in turbocharger speedand hence lower charge air pressure,which in turn causes an increase inexhaust gas temperature. To maintainthe required engine output in certainapplications, e.g. baseload diesel powerplants, the loss of engine power is com-pensated by additional fuel injection.

Cylinder outlet tempera-ture vs turbocharger turbine inlet temperatureWhen wet cleaning turbocharger turbines on 4-stroke dieselengines it is important to maintain the correct turbine inlet temperature. But as Manfred Schumm explains, this can oftenonly be estimated.

1.0

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0.0

0 90 180 270 360

Degrees crankshaft angle

450 540 630 720

Valv

e lift

Exhaust

Intake

300 °

Valve timing example of a 4-stroke diesel engine.

36 ABB charge! 1|11

Tips for the operator

ABB Turbocharging specifies a seriesof parameters aimed at minimizing thesestresses during wet cleaning. Of these,limits for exhaust gas temperature aheadof the turbine, both before and duringwet cleaning, are the most important.

As we have seen, if the engine opera-tor uses the cylinder outlet temperatureto set the turbine inlet temperature, it ispossible that the actual temperatureahead of the turbocharger will be 100 to140 °C higher than assumed. The resultis the excessive thermal stresses men-tioned in the turbine housing and at thenozzle ring. And after only a few wetcleaning intervals performed at exces-sive exhaust gas temperature ahead ofthe turbine, the visible results could behairline cracks and even material parti-cles breaking off these components. Inaddition, the inadmissible stresses in -volved can cause distortion of flangesand hence lead to fluid leakages (gasand cleaning water).

How do these differences in the meas-ured temperatures occur?

A thermocouple in front of the turbineis permanently in the exhaust gas flow,and at constant engine load it is sur-rounded by gases with a more or lesshomogeneous temperature and flow. It isthus capable of measuring the real tur-bine inlet temperature.

By contrast, the thermocouple afterthe cylinder is subjected to changingconditions, principally due to the inter-

mittent flow of exhaust gases from thecylinder as the exhaust valve opens andcloses. It is thus not constantly sur-rounded by hot gas.

The cycle of a cylinder on a 4-strokeengine comprises 720 ° of crankshaftangle – i. e. two revolutions – anddepending on timings, the exhaust valvecan be open during about 300 of the720 °. This means the sensor is subjectedto hot gases for less than half the 4-strokes. No gas is flowing during theremaining period and the sensor coolsdown.

Another important factor is that valveoverlap is used to achieve “scavenging”of the cylinder – i. e. the inlet valve openswhile the exhaust valve is still open andmuch cooler charge air pushes theexhaust gases out of the cylinder. Theinevitable mixing of the air and theexhaust gases leads to further cooling ofthe temperature sensor.

The sensor after the cylinder thus experi-ences three different situations:1. Exhaust valve open:

hot gas is flowing past the sensor2. Exhaust and inlet valves both open:

a mixture of hot gases and relativelycool air is flowing past the sensor

3. Exhaust valve closed:the sensor is immersed in a relativelycool “scavenging pocket”

These variations combined with theinertia of the sensor during the rapid

temperature fluctuations and the con-struction of the sensor lead to a form of“averaging” of the temperature read-outseen by the engine end user.

Which proportion each of the threestates mentioned above contribute tothe overall conditions around the sensordepends on the position of the sensor,the engine’s valve timings, valve overlapand the scavenging gradient, i. e. the dif-ference between the charge air pressureand the pressure after the cylinder, whichin turn is influenced by the turbochargerspecification.

It also often occurs that the differentcylinder outlet temperatures deviate moreor less strongly from one another, whichmay derive from variations in combustionquality from cylinder to cylinder or inter-action between neighboring cylinders viathe exhaust gas collector system. This isinfluenced by the engine’s firing order(pressure wave from one cylinder coun-teracting the exhaust outflow fromanother).

Summary The quintessence is that cylinder out-

let temperature is not identical with tur-bocharger turbine inlet temperature andthe effects of wet cleaning turbochargerturbine side components at too high atemperature can be severely detrimental.

The engine end user should try to hitABB Turbocharging’s recommended tem-perature range based on turbochargerturbine inlet temperatures 100 to 140degree higher than cylinder outlet tem-perature.

Moreover, it may be necessary toadjust exhaust gas temperature by fur-ther reducing engine load after the startof wet cleaning due to the effects of thecleaning water described above.

The range 100 to 140 °C temperaturewe quote is based on experience fromthe field, gathered on several enginetypes. The band width of 40 degrees isderived from various parameters andinfluences. It is intended to serve as aguide for engine users for setting a suit-ably accurate exhaust gas temperatureahead of the turbocharger during wetcleaning when there is no temperaturesensor at the turbine inlet.

Only the well insulated exhaust gas collector (running along the center line of this vee engine) sepa-rates the engine’s cylinders from its turbocharger(s). Nonetheless, temperatures at the turbine inletcan be over 100 °C higher than at the exhaust ports.

ABB charge! 1|11 37

Recipe

BibimbapInternational recipe No 2Text Asiart Jeonju (Tour) – Maangchi’s blog, Photo contributed by Rural Development Association (RDA), Korea

Since the engine builders of South Koreaare at the center of our story about theNOL contract and the A100-L, we chosea Korean dish for our classic internationalrecipe.

Bibimbap is cited as one of the threebest dishes from the era of the KoreanChosun dynasty. “Now, it is one of thebest-known Korean foods international-ly,” notes Hyun-Ji Lim, assistant sectionchief at the ABB Turbocharging office inBusan, Korea. “It consists of a base ofcooked rice, topped with thirty differentvegetables along with a fried egg (ifdesired), pine nuts and other sauces andingredients. It thus offers an excellentbalance of proteins, vitamins, minerals,carbohydrates and fat. Also, it’s consid-ered to contain the wisdom and philoso-phy of ancient Korea.”

Harmony of taste and appearance All Bibimbap ingredients are carefully

chosen based on the Ying and Yang andFive Elements Principle. They are in greatharmony both visually and in taste. Tocreate “traditional” Bibimbap more than30 vegetables are needed, but here is asimplified version.

Ingredients (makes 4 – 6 servings) – boiled rice – a packet of bean sprouts – a bunch of spinach – 2 small size of zucchinis (courgettes) – 5 – 7 Shiitake mushrooms – fern brakes (kosari) – 200 grams of ground (minced) beef – 1 small carrot, – fried eggs (optional)– bean soy sauce, garlic, black pepper,

sesame oil, vegetable oil, pine nuts,hot pepper paste.

Cooking instructionsCook the rice. Rinse the bean sprouts

3 times and put them in a pot with a cupof water. Add 1 teaspoon of salt andcook for 2 minutes. Drain and mix with aclove of minced garlic, sesame oil and apinch of salt.

Put the spinach in boiling water andstir for 1 minute. Rinse it in cold water afew times and squeeze lightly. Mix with a pinch of salt, 1 teaspoon of soy sauce,1 clove of minced garlic and sesame oil.

Cut 2 small zucchinis (courgettes) intothin strips, sprinkle with a pinch of saltand mix together. Leave for a few min-utes and then sauté them in a pan over ahigh heat. When cooked, the zucchiniswill look a little translucent.

Prepare about 2 or 3 cups of fernbrakes (kosari) for 4 servings, (50 %more for 6). Cut into pieces 5 – 7 cm longand sauté in a pan with 1 teaspoon ofvegetable oil. Stir and add 1 tablespoonof soy sauce, 1⁄2 a tablespoon of sugar,and cook for 1 to 2 minutes. Add sesameoil.

Slice shitake mushrooms thinly andsauté with 1 teaspoon of vegetable oil.Add 2 teaspoons of soy sauce and 1 or 2teaspoons of sugar and stir for 2 minutes.Add some sesame oil.

Put some oil and 200 grams (1⁄2pound) of ground (minced) beef into aheated pan and stir. Add 4 cloves ofminced garlic, 1 tablespoon of soysauce, 1⁄2 a tablespoon of sugar, a littleground black pepper. Add sesame oil.

Cut a carrot into strips, sauté for 30seconds.

Put the rice into a big bowl andattractively arrange the vegetables andmeat. According to taste, add an eggfried “sunny side up” at the center.

Serve with sesame oil, pine nuts andhot pepper paste.

Finally mix it up and eat it! Hyun-Ji and charge! wish you a good

appetite and hope you will taste the har-mony of flavors from Korea!

38 ABB charge! 1|11

Acknowledgments

Preview charge 2/2011 China special

As well as the accustomed mix of interesting reports from our ABB Turbocharging world, in ournext issue we look at the remarkablerise of the fastest growing market for engines and turbochargers.

Published byABB Turbo Systems Ltd

AddressP.O. BoxCH-5401 Baden/SwitzerlandPhone: +41 58 585 7777Fax: +41 58 585 5144www.abb.com/turbocharginge-mail: charge@ch.abb.com

EditorsJonathan WalkerValentin Bregy

Contributing editorsDaniel BütlerTiziana Ossola Auf der Maur

TranslationJonathan WalkerMalcolm Summers

PhotosMichael ReinhardAlex Spichale ShutterstockiStockphotoNOL GroupRolls-RoyceWärtsilä

Cover photo: Shutterstock

PrinterDietschi AG Druck & Medien, Olten /Switzerland

Layout, typography, electronic publishingDomino Style & Type AG, Wettingen /Switzerland

Reprints require the publisher’s written consent.

© 2011 ABB Turbo Systems Ltd, Baden /SwitzerlandAll rights reserved

ABB charge! 1|11 39

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