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The eng ine types of the MC progra mme a re

ide ntified by the follow ing letters a nd figures :

MAN B &W Diesel A/S S 50MC-C P rojec t G uide

430 100 100 198 21 20

1.01

Fig. 1 .01: Engine type designation

178 34 41-3.1

S 50 MC

Diameter of piston in cm

S troke/b ore ra tio

Engine programme

C Compa ct engine

S S tationary engine

S S uper long stroke a pproxima tely 4.0

L Long s t roke approximately 3 .2

K Short s t roke approximately 2 .8

-C6

Numb er of cy linde rs

Design

Concept

C Ca msha ft co ntrolled

E Elec tronic co ntrolled (Intellig ent Engine)

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S50MC-CBore: 500mmStroke:2000mm

430 100 100 198 21 21


1.02

Power and speed

LayoutEngine s peed

Mean effectivepressure

P ower kWB HP

Numbe r of cylinde rs

r/min ba r 4 5 6 7 8

L1 127 19.0 6320

85807900

107259480

128701106015015

1264017160

L2 127 12.2 4040

550050506875

60608250

70709625

808011000

L3 95 19.0 4740

644059258050

71109660

829511270

948012880

L4 95 12.2 30404120 38005150 45606180 53207210 60808240

Fuel and lubricating oil consumption

Specific fuel oilconsumption

g/kWhg /B HP h

Lubrica ting oil co nsumption

At loa dLayout po int

Withhigh efficiencyturbocharger

With conventionalturbocharger

Sys tem oilApproximate

kg/cyl. 24 ho urs

Cylinder oilg/kWhg /B HP h100% 80% 100% 80%

L1 171

126169124

174128

171126

4 - 5 0.95-1.5

0.7-1.1

L2 159

117156116

162119

160118

L3 171

126169124

174128

171126

L4 159

117156116

162119

160118

Fig. 1.02: Power, speed and SFOC 178 39 14-7.1

L3

L4

L2

L1

Po w e r

Speed

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EnginePowerRangeandFuel Consumption

Engine Power

The tab le co ntains da ta rega rding the engine power,

speed and s pecific fueloilc onsumption of the engine.

Engine power is specified in both BHP and kW, in

rounde d figures, for ea ch c ylinder number and layout

points L1, L2 , L3 and L4:

L1 designates nominal maximum continuous rating

(nominal MCR), at 100% engine power and 100%

engine speed . L2 , L3 and L4 des igna te la yout points

a t the other three co rners of the la yout a rea, cho s enfor ea s y reference . The mea n effective pres sure is:

L1 - L3 L2 - L4

ba rkp/cm 2

19.019.3

12.212.4

Overload corresponds to 110% of the power at

MCR, and may be permitted for a limited period of

one ho ur every 12 hours.

The engine power figures g iven in the ta bles rema in

va lid up to tropica l co nditions a t se a level, i.e.:

B low er inlet temp erature . . . . . . . . . . . . . . . . 45 °C

B low er inlet press ure . . . . . . . . . . . . . . . 1000 mba r

S ea wa ter temperature . . . . . . . . . . . . . . . . . . 32 °C

Specific fueloil consumption(SFOC)

Spec ific fuel oil consump tion values refer to brake

power, and the following reference conditions:

ISO 3046/1-1986:B low er inlet temp erature . . . . . . . . . . . . . . . . 25 °C

B low er inlet press ure . . . . . . . . . . . . . . 1000 mba r

Cha rge a ir coolant te mperature . . . . . . . . . . . 25 °C

Fuel oil low er c a lorific va lue . . . . . . . . 42,700 kJ /kg

(10,200 kca l/kg)

Although the engine will develop the power speci-

fied up to tropical ambient conditions, specific fuel

oil co nsumpt ion va ries w ith a mbient co nditions a nd

fuel oil low er ca lorific va lue. For ca lculation of these

changes, see the following pages.

Highefficiency/conventional turbochargers

The eng ine is in its b a sis d es ign ma de with a high

efficiency turboc ha rger in order to o bta in the low -es t pos sible S pec ific Fuel Oil Co nsumption

(S FOC ).

The a mount of a ir req uired for the comb ustion ca n

however be a djusted to provide a higher exhaust

ga s tempera ture, if this is needed for exhaust ga s

bo iler by a pplying “co nventiona l” turbo cha rger,

- see s ection 2.

VIT fuelpumps

The eng ine type is in its b asis d es ign not fitted with the

Variable Injec tion Timing (VIT) fuel pumps, - but they

can optionally (4 35 104)be equipped with VITpumps,

and in tha t ca se they ca n be optimised betw een 85 -

100% of spec ified MCR (point M), - see s ec tion 2.

SFOC guarantee

The figures g iven in this p rojec t g uid e repres ent the

values ob ta ined w hen the engine and turboc harger

are matched with a view to obtaining the lowest

possible SFOC values and fulfilling the IMO NOxemiss ion limita tions .

The S pec ific Fuel Oil C ons umption (S FOC) is gua r-anteed for one engine load (power-speed combina -tion), this being the one in which the engine is opti-mised. Theguaranteeisgivenwithamarginof5%.

As SFOC and NOx are interrelated parameters, anengine offered without fulfilling the IMO NOx limita -tions is sub jec t to a toleranc e of only 3% of the SFOC.

Lubricating oildata

The c ylinde r oil cons umption figures sta ted in the

tables are valid under normal conditions. During

running-in p eriode s a nd under s pecial c onditions,

feed rates of up to 1.5 t imes the stated values

should be used.


400 000 060 198 21 22

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430 100 500 198 21 23


1.04

Fig. 1 .03: Performance c urve for S50MC- C w i thout VIT fuel pumps

178 16 06-9.0

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The fra me b ox is atta ched to the b edplate with

sc rews. The fra me bo x, bedplate a nd cylinder fra me

a re tightened toge ther by tw in sta y bo lts. The sta ybo lts a re mad e in one or tw o pa rts (option: 4 30 132)

depending on the engine room height.

Cylinder Frame,Cylinder LinerandStuffing Box

The cylinde r fra me is c a st in one or more piec es w ith

integ rated c a ms ha ft fra me and the cha in drive at the

a ft end . It is ma de of ca st iron a nd is a tta c hed to the

fra me b ox w ith s crews . The c ylinder fra me is pro-

vided w ith a cc ess co vers for cleaning the sca venge

a ir spa ce a nd for inspec tion of sc a venge ports andpist on rings from the c a ms ha ft side . Tog ether with

the cylinder liner it forms the scavenge air space.

The c ylinde r frame ha s duc ts for pist on c oo ling o il

in le t . The sc a venge a ir rece iver , c ha in d rive ,

turboc harger, air cooler box and ga llery brackets

are located at the cylinder frame. Furthermore, the

supp ly pipe for the pisto n co oling o il a nd lubrica ting

oilis atta che d to the cy linde r fra me. At the botto m of

the c ylinde r fra me there is a piston rod s tuffing b ox,

which is provided with sealing rings for scavenge

a ir, a nd w ith oil sc rape r rings w hich prevent oil fromco ming up into the sc a venge a ir spa ce.

Drains from the scavenge air space and the piston

rod stuffing bo x are loc a ted a t the bo ttom of the cy l-

inde r fra me.

The cylind er liner is ma de o f alloyed c a s t iron and is

sus pended in the cylinder frame by mea ns of a low

situate d fla nge . The uppe rmost pa rt of the liner is

surrounded by a ca s t iron coo ling jac ket. The c ylin-

der liner has scavenge ports and drilled holes for

cylinder lubrication.

The c a msha ft is embed ded in b ea ring shells lined

with white meta l in the c a msha ft fra me.

Cylinder Cover

The c ylinder c over is of forged steel, ma de in one

piece , and ha s b ores for co oling wa ter. It has a cen-

tral bore for the exhaust valve a nd bores for fuel

valves, sa fety valve, sta rting valve a nd indica tor

valve.

The c ylinde r cover is a tta che d to the c ylinde r frame

w ith 8 stud s and nuts tighte ned by hydraulic ja c ks.

Exhaust Valve and Valve Gear

The exha ust va lve co nsists of a va lve housing and a

va lve s pindle. The va lve hous ing is of c a st iron a nd

a rra nge d for wa ter coo ling. The hous ing is provide d

with a bo ttom piece of steel with a fla me ha rdened

se a t. The bo ttom piece is w a ter coo led . The sp indle

is ma de of heat res ista nt steel with hardfa cing meta l

w elded o nto the se a t. The hous ing is provided w ith aspindle guide.

The exha ust va lve is tightene d to the cy linde r cover

with studs a nd nuts. The exhuas t valve is opened

hydra ulica lly and c los ed by mea ns of a ir press ure. In

operation, the va lve s pindle slowly rotates , d riven

by the exha ust ga s ac ting on sm a ll va nes fixed to the

spindle. The hydra ulic sys tem c onsists of a piston

pump mounted on the roller g uide housing, a

high-pressure pipe, and a working cylinder on the

exhaus t va lve. The piston pump is a ctiva ted by a

ca m on the ca mshaft.

Air sea ling of the exha ust va lve s pindle guide is

provided.

Fuel Valves, Starting Valve,Safety Valve and Indicator Valve

Each cylinder cover is eq uipped with tw o fuel

valves, one starting valve, one safety valve, and one

indica tor va lve. The opening of the fuel valves is

co ntrolled by the fuel oil high pressure c rea ted by

the fuel pumps , and the valve is clos ed by a s pring.

An a utoma tic vent s lide a llow s c ircula tion o f fuel oil

through the valve and high pres sure pipes , and p re-

vents the co mpress ion cha mb er from being filled up

with fuel oil in the event that the valve spindle is

sticking when the eng ine is s topped . Oil from the

vent slide a nd other drains is led a wa y in a c los ed

system.

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The s ta rting va lve is ope ned by co ntrol a ir from the

starting air distributor and is closed by a spring.

The sa fety valve is s pring-loa de d.

Indicator Drive

In its basic execution, the engine is fitted with an in-

dicator drive.

The indica tor drive c onsists of a ca m fitted on the

ca mshaft and a spring-loa ded spindle with roller

which moves up and dow n, corresponding to the

movem ent of the p is ton w ithin the eng ine c ylinde r.

At the top, the sp indle has a n eye to w hich the indi-ca tor cord is fastened after the indica tor has been

mounted on the indicator valve.

Crankshaft

The cra nksha ft is of the semi-built type . The se mi-built

type is mad e from forged or ca st steel throw s. The

crankshaft incorporates the thrust shaft.

At the aft end, the crankshaft is provided with a

fla nge for the turning w heel and for coupling to theintermediate shaft.

At the front end , the cra nksha ft is fitte d w ith a fla ng e

for the f it t ing of a tuning wheel a nd/or c oun-

terweights for ba la ncing purpos es, if neede d. The

flange can also be used for a power take-off, if so

de sired . The pow er ta ke-off ca n be supplied a t extra

cost, option: 4 85 000.

Coupling bolts and nuts for joining the crankshaft to-

ge ther with the intermediate sha ft a re not norma lly sup-

plied. These can be ordered a s a n option: 4 30 602.

Axial Vibration Damper

The eng ine is fitted with a n a xia l vibra tion d a mper,

w hich is mo unted on the fore end of the cra nksha ft.

The da mper cons ists of a piston a nd a split-type

housing loc a ted forwa rd of the foremos t main bear-

ing. The pis ton is ma de a s a n integ rated c olla r on the

main journal, and the housing is fixed to the main

bea ring s upport. A mecha nica l device for check of

the functioning o f the vibra tion d a mper is fitted .

5 and 6-cylinde r eng ines a re eq uipped w ith an a xia l

vibration monitor (4 31 117).

P la nts eq uipped w ith P ow er Ta ke Off a t the fore end

a re a lso to be eq uipped w ith the axial vibra tion mon-

itor, option: 4 31 116.

Connecting Rod

The connec ting rod is ma de o f forged o r ca st s teel

and provided with bea ring c aps for the crosshea d

a nd c rankpin bea rings .

The cross hea d and c rankpin bea ring ca ps a re se -

cured to the c onnect ing rod by s tuds and nuts

which a re tightened by hyd raulic ja cks.

Th e c r o s s h e a d b e a r in g c o n s is t s o f a s e t o f

thin-walled steel shells, lined with bearing metal.

The cross hea d b ea ring c a p is in one piece , with an

angular cut-out for the piston rod.

The cra nkpin bea ring is provided w ith thin-wa lled s tee l

shells, lined with bearing metal. Lub. oil is suppliedthrough ducts in the crosshead and connecting rod.

Piston, Piston Rod and Crosshead

The piston c onsists of a piston c rown and piston

skirt. The piston c row n is ma de of hea t-resista nt

s t e e l a n d h a s f o u r r in g g r o o v e s w h ic h a re

hard-chrome plated on b oth the upper and lower

surfa ces of the grooves . The piston c rown is with

“high topland”, i.e. the distance between the piston

top a nd the upper piston ring ha s b een increas ed.

The upper piston ring is a CP R type (Co ntrolled

P ressure Releif) a nd is higher than the other piston

rings. The other three piston rings are with a n

obliq ue cuts.

The pist on s kirt is o f ca s t iron.

The p is ton rod is o f fo rged s tee l a nd is sur-

face-hardened on the running surface for the stuff-

in g b o x . Th e p i s t o n ro d is co n n e c t e d t o t h e


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cross hea d w ith four sc rew s. The piston rod ha s a

ce ntral bore w hich, in conjunction w ith a co oling o il

pipe, forms the inlet and outlet for cooling oil.

The c ross head is of forged steel and is provided

with ca st s teel guide s hoes with white meta l on the

running surface.

The te les c op ic p ipe fo r oil inlet a nd t he pipe fo r oil

outlet a re mounted on the top o f the guide s hoes.

Fuel Pump and Fuel OilHigh-Pressure Pipes

The eng ine is provided w ith one fuel pump for ea chcy linde r. The fuel pump co nsists of a pump ho using

of nodular ca st iron, a c entrally pla ce d pump ba rrel,

a nd plunger of nitrated s teel. In orde r to prevent fuel

oil from being mixed with the lubricating oil, the

pump actuator is provided with a sealing arrange-

ment.

The pump is a ctivate d b y the fuel ca m, a nd the vol-

ume injected is controlled by turning the plunger by

mea ns of a toothed ra ck co nnected to the regulating

mechanism.

In the ba sic de s ign the a djustm ent of the pump lea d

is effecte d by inse rting shims betw een the top cover

a nd the pump housing.

The eng ine c a n a s a n option: 4 35 104 be fitted w ith

fuel pumps with Variable Injection Timing (VIT) for

optimise d fuel ec ono my a t pa rt loa d. The VITprinci-

ple uses the fuel regulating shaft position as the

controlling parameter.

The roller guide hous ing is provided w ith a ma nual

lifting de vice (4 35 130)w hich, d uring turning of the

eng ine, c a n lift the roller guide free of the ca m.

The fuel oil pumps a re provided with a puncture

valve, which prevents high pressure from building

up during normal stopping a nd s hut dow n.

The fuel oil high-press ure p ipes a re eq uipped w ith

protective hoses and are neither heated nor insu-

lated.

Camshaft and Cams

The ca msha ft is ma de in one or two pieces d epend-ing o n the number of c ylinde rs, w ith fuel ca ms , ex-

haust c ams , indica tor cams , thrust disc and cha in

wheel shrunk onto the s haft.

The exhaust ca ms a nd fuel ca ms a re of steel, with a

ha rdened roller rac e. They ca n be a djust ed a nd dis-

ma ntled hydra ulica lly.

Chain Drive

The ca ms ha ft is d riven from the cra nksha ft by two

cha ins. The c hain wheel is bo lted o n to the s ide ofthe thrus t co lla r. The c ha in drive is p rovided w ith a

cha in tightener and guide b a rs to s upport the long

cha in lengths.

Reversing

Reversing of the engine ta kes pla ce b y mea ns of a n

a ngular displac ea ble roller in the driving mecha nis m

for the fuel pump of ea c h eng ine c ylinde r. The re-

versing mechanism is activated and controlled by

co mpresse d a ir supplied to the engine.

The exha ust va lve g ea r is no t reversible.

2nd order Moment Compensators

These a re relevant only for 4, 5 or 6-cylinder e n-

gines, and c a n be mounted either on the aft end or

on both fore end and a ft end. In spec ia l ca ses only a

compensator on the fore end is necessary.

The af t-end co mpensa tor co nsists of ba la nce-

we ights built into the c a msha f t cha in drive , op-

tion: 4 31 203.

The fore-end compens a tor consists of ba la nce-

weights driven from the fore end of the crankshaft,

option: 4 31 213.

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tions a re ac hieved. S ome ma in pipes of the engine

are s uspended from the g allery brac kets, a nd the

upper gallery platform on the camshaft side is pro-vide d with ove rhauling holes for pisto n. The numbe r

of holes depend s on the number of cylinders.

The eng ine is prepa red for top brac ings on the ex-

ha ust s ide (4 83 110), or on the c a ms ha ft side (op-

tion: 4 83 111).

Scavenge AirSystem

The a ir intake to the turboc harger ta kes pla ce di-

rectly from the engine room through the intake si-

lencer of the turbo cha rger. From the turbocha rger,the a ir is led via the c ha rging a ir pipe, a ir coo ler and

scavenge air receiver to the scavenge ports of the

cy linde r liners. The c ha rging a ir pipe be tw een the

turboc harger a nd the a ir cooler is provided with a

compensator and is heat insulated on the outside.

See chapter 6.09.

Exhaust Turbocharger

The en g ine ca n be fitte d w ith MAN B&W (4 59 101) ,

AB B (4 59 102) or MHI (4 59 103)turboc ha rgers a r-rang ed on the a ft end o f the eng ine (4 59 121).

Alternatively, on this engine type the turbocharger

ca n be loca ted on the exhaust side of the engine,

option: 4 59 123.

The turboc ha rger is p rovide d w ith:

a ) Equipment for wa ter wa shing of thecompressor s ide

b) Eq uipment for dry clea ning o f the turbine side

c) Water washing on the turbine side is mountedfor the MAN B&W a nd AB B turbo cha rgers.

The g a s o utlet ca n be 15°/30°/45°/60°/75°/90° from

vertica l, aw a y from the engine. S ee either of options

4 59 301-309. The turboc ha rger is e q uipped w ith a n

electronic tacho system with pick-ups, converter

and indicator for mounting in the engine control

room.

Scavenge Air Cooler

The eng ine i s f it ted wi th a ir c oo ler(s) o f themonoblock type, one per turboc harger for a s ea wa -

ter cooling system designed for a pressure of up to

2.0-2.5 b a r w orking press ure (4 54 130) or central

co oling w ith fres hw a ter of ma ximum 4.5 ba r w orking

press ure, o ption: 4 54 132. The a ir coo ler is so de-

signed that the difference between the scavenge air

temperature a nd the w a ter inlet tempe ra ture (a t the

optimis ing point)ca n be kept a t a ma ximum of 12°C.

The end c ove rs a re of coa ted ca s t iron (4 54 150), or

a lternatively of b ronze, o ption: 4 54 151

The c oo ler is provide d w ith eq uipment forcleaning of:

Air side:

S tand ard s howering s ystem (cleaning pumpunit including tank and filter, yard supply)

Water side:

Cleaning brush

Exhaust Gas System

From the exhaust valves, the gas is led to the ex-haust gas receiver where the fluctuating pressure

from the individual cylinders is equalised, and the

t o t a l v o lu m e o f g a s le d f u rt h e r o n t o t h e

turboc harger at a consta nt press ure.

Compensa tors are f it ted be tween the exhaust

valves and the receiver, and between the receiver

and the turbocharger.

The exhaust ga s receiver and exhaust pipes are

provided with insulation, covered by ga lvanized

steel plating.

There is a protective g rating b etwe en the exha ust

ga s receiver a nd the turbocha rger.

After the turbo cha rger, the ga s is led via the exha ust

ga s outlet trans ition piece, o ption: 4 60 601 and a

co mpensa tor, option: 4 60 610 to the e xternal ex-haus t pipe sys tem, which is ya rd’s supply. Se e also

cha pter 6.10.

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Auxiliary Blower

The eng ine is pro vid ed w ith tw o elec tric a lly-drivenblow ers (4 55 150). The s uct ion s ide of the b lowe rs

is co nnected to the sca venge a ir spa ce a fter the air

cooler.

Betw een the airc ooler a nd the sca venge air receiver,

non-return valves a re fitted which a utoma tica lly

close when the auxiliary blowers supply the air.

B oth auxilia ry blow ers will sta rt ope rating before the

eng ine is sta rted and will ens ure suffic ient sca veng e

a ir pressure to obta in a s a fe sta rt.

During o pera tion o f the eng ine, b oth a uxilia ry blow -ers will s ta rt a utoma tica lly eac h time the engine loa d

is red uce d to a bo ut 30-40%, and the y w ill co ntinue

operating until the loa d ag ain exceeds approxi-

mately 40-50%.

In ca se s w here one of the auxilia ry blow ers is out of

se rvice , the other a uxilia ry blow er will a utoma tic a lly

compensate without any manual readjustment of

the valves, thus avo iding any eng ine loa d reduction.

This is a chieved by the automa tica lly working

non-return va lves in the s uction pipe of the blow ers.

The electric mo tors a re of the tota lly enc los ed , fan

co oled, single s peed type, w ith insulation min. clas s

B and enclosure minimum IP44.

The electrica l c ontrol pa nel a nd s ta rters for two

a uxilia ry blow ers ca n be del ivered a s a n option:

4 55 650.

Piping Arrangements

The eng ine is delivered w ith piping arra ng eme nts for:

Fuel oil

Heating of fuel oil pipes

Lubrica ting a nd pisto n co oling o il pipes

Cylinder lubricating oil

Lubricating of turbocharger

Sea cooling wa ter

J ac ket cooling wa ter

Cleaning of turboc harger

Fire extinguishing for scavenge air space

S tarting a ir

Co ntrol a ir

S afety air

Oil mist de tec tor.

The pipes for se a co oling wa ter to the a ir co olera re of:

G a lva nise d s teel . . . . . . . . . . . . . . . . . 4 45 130, or

Thick-wa lled, ga lvanised ste el . o ption 4 45 131, or

Aluminium bra ss . . . . . . . . . . . . o ption 4 45 132, or

Co pper nickel. . . . . . . . . . . . . . . . . option 4 45 133

In the cas e of central co oling, the pipes for fres hwa -ter to the a ir coo ler are of s teel.

The pipes a re provide d with so ckets for sta nda rd in-struments, alarm and safety equipment and, fur-thermore, with a numb er of so ckets fo r supp leme n-tary signal equipment and supplementary remote

instruments.

The inlet a nd return fuel oil pipes (exc ept bra nch

pipes)are heated with:

S tea m trac ing . . . . . . . . . . . . . . . . . . . 4 35 110, or

Elec trica l trac ing . . . . . . . . . . . option: 4 35 111, or

Therma l oil trac ing . . . . . . . . . . . . o ption: 4 35 112

The dra in pipe is hea ted b y fres h coo ling w a ter.

The a bove heating pipes a re normally delivered

without insulation, (4 35 120). If the engine is to be

tra nsported a s o ne unit, insula tion ca n be mounted

a s a n option: 4 35 121.

The eng ine’s e xterna l pipe conne c tions a re in ac -corda nce with DIN a nd IS O sta nda rds .


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2 EngineLayoutandLoadDiagrams

Introduction

The effec tive brake pow er “P b ” of a d ies el engine is

proportional to the mean effective pressure p e a nd

eng ine spee d “n”, i.e. when using “c” a s a co nsta nt:

P b = c x pe x n

so, for constant mep, the power is proportional to

the speed:

P b = c x n1

(for consta nt mep)

When running w ith a Fixed P itch P rope ller (FP P ), the

pow er ma y be express ed a cc ording to the propeller

law a s:

P b = c x n3

(prope ller la w )

Thus, for the a bo ve exa mples, the brake pow er P bma y be express ed a s a po we r function of the speed

“n” to the p ow er of “i”, i.e.:

P b = c x ni

Fig. 2.01a show s the relationship for the linea r func-

tions, y = a x + b, using linea r sc a les.

The po w er functions P b = c x ni, s ee Fig. 2.01b, w ill

be linear functions when using logarithmic scales.

log (P b ) = i x log (n) + log (c )

Thus, prope ller curves w ill be pa rallel to lines ha ving

the inclina tion i = 3, and lines w ith cons ta nt mep will

be parallel to lines with the inclination i = 1.

Therefore, in the Layout Diagrams a nd Loa d Dia-

grams for diesel engines, logarithmic scales are

used, making simple diagrams with straight lines.

Propulsion and Engine Running Points

Propellercurve

The rela tion betw een pow er a nd propeller spee d for

a fixed pitch propeller is as mentioned above de -

sc ribe d b y mea ns o f the prope ller la w , i.e. the third

pow er curve:

P b = c x n3

, in which:

Pb = eng ine pow er for propulsion

n = propeller speed

c = co ns t ant

Propeller designpoint

Norma lly, e stimations of the neces sa ry propeller

power and speed are ba sed on theoretica l ca lcula-

tions for loa ded ship, and often experimental tank

tests, both as suming optimum operating condi-

tions , i.e. a clea n hull a nd go od w ea ther. The com bi-

nation of speed a nd pow er obta ined ma y be ca lled

the ship’s propeller de s ign po int (P D), pla ce d on the


402 000 004 198 21 26

2.01

Fig. 2.01b: Power function curves in logarithmic scales

178 05 40-3.0

Fig. 2.01a: Straight lines in linear scales

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lig ht running prope ller curve 6. S ee Fig. 2.02. On the

other hand, s ome shipyards, a nd/or propeller ma nu-

facturers sometimes use a propeller design point(P D’) that incorporates a ll or part o f the s o-ca lled

sea margin described below.

Fouledhull

When the ship ha s s a iled for s ome time, the hull a nd

propeller bec ome fouled a nd the hull’s res ista nce

will increas e. C onse q uently, the ship spee d will be

reduc ed unles s the eng ine d elivers more pow er to

the prop eller, i.e. the p rope ller will b e further loa de da nd w ill b e he a vy running (HR).

As mode rn vess els with a rela tively high s ervice

speed are prepared with very smooth propeller and

hull surfa ces , the fouling a fter sea tria l, therefore,

w ill involve a rela tively highe r resista nce a nd thereby

a heavier running propeller.

Seamarginand heavypropeller

If , at the s ame time the w eather is ba d, w ith headwinds, the ship’s resistance may increase com-

pa red to operating a t ca lm wea ther co nditions.

When de termining the ne ce ss a ry engine pow er, it is

therefore normal practice to add an extra power

ma rgin, the so -ca lled s ea m a rgin, which is trad ition-

a lly a bo ut 15% of the propeller des ign (P D) pow er.

Engine layout(heavypropeller)

When d etermining the nec ess a ry engine s peed

considering the influence of a heavy running propel-ler for operating at large extra ship resistance, it is

recommended - compared to the clean hull and

ca lm wea ther propeller curve 6 - to choos e a heavier

propeller curve 2 for eng ine la yout, a nd the propeller

curve for clean hull a nd c a lm w ea ther in curve 6 will

be s a id to repres ent a “lig ht running” (LR)prope ller.

Compa red to the hea vy engine layo ut curve 2 we

recommend to use a light running of 3.0-7.0% for

de s ign o f the propeller.

Engine margin

Bes ides the sea margin, a so-ca lled “engine mar -

gin” of s ome 10% is freq uently a dd ed . The c orre -

sp ond ing po int is c a lled the “spe cified MC R for pro -

pulsion” (MP), and refers to the fact that the power

for point SP is 10% lower than for point MP. Point

MP is ide ntica l to the eng ine’s s pec ified MCR point

(M)unles s a ma in engine driven sha ft genera tor is in-

stalled. In such a case, the extra power demand of

the shaft generator must also be considered.

Note:

Light/heavy running, fouling and sea margin are

overlapp ing terms. Light/heavy running of the p ro -

peller refers to hull and prop eller deterioration and

heavy weather and, –sea margin i.e. extra power to

the propeller, refers to the influence of the w ind and

the sea. However, the degree of light running must

be dec ided upon experience from the actual trade

and hull design.

402 000 004 198 21 26


2.02

Line 2 P ropulsion curve, fouled hull a nd hea vywe a ther (hea vy running), rec omme nde d for en-gine layout

Line 6 P ropulsion curve, clea n hull and ca lm wea ther(light running), for propeller layout

MP Spec if ied MCR for propulsionSP Continuous service rating for propulsion

PD Propeller design point

HR Heav y run nin g

LR Light running

Fig. 2.02: Ship propulsion running points and engine layout

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Engine Layout Diagram

An engine’s layout d ia gram is limited by two co n-

sta nt mea n effec tive press ure (mep) lines L1-L3 and

L2-L4, a nd by two co nst a nt eng ine spee d lines L1-L2and L3-L4, s ee Fig. 2. 02. The L1 point refers to theengine’s nominal maximum continuous rating.

Within the layout area there is full freedom to select

the eng ine’s sp ec ified MC R point M w hich s uits the

dema nd of propeller pow er a nd spee d for the ship.

On the horizonta l a xis the e ngine s peed a nd on the

vertica l a xis the engine pow er a re show n in percent-

a ge sc a les . The sca les a re log a rithmic which mea ns

tha t, in this d ia gra m, pow er function curves like pro-

peller curves (3rd power), constant mean effective

pressure c urves (1st power) and consta nt s hipsp eed c urves (0.15 to 0.30 pow er)a re stra ight lines .

Specifiedmaximumcontinuous rating(M)

B a se d on the propuls ion a nd eng ine running po ints,

a s previous ly found, the la yout diag ram of a releva nt

ma in engine ma y be dra w n-in. The s pec ified MC R

point (M) must be inside the limita tion lines of t he

layout diagram; if it is not, the propeller speed will

have to be changed or another main engine type

must be c hosen. Yet, in spec ia l ca se s point M may

be located to the right of the line L 1-L2, se e “Opti -

mising P oint” be low .

Continuousservice rating(S)

The Co ntinuous s ervice rating is the p ow er at w hich

the engine is normally assumed to operate, and

point S is identical to the service propulsion point

(S P ) unles s a ma in engine driven sha ft generator is

installed.

Optimising point (O)=specified MCR (M)forenginewithoutVIT

The eng ine type is in its b a s ic d es ig n not fitted w ith

VITfuel pumps , so the s pec ified MC R is the po int at

which the engine is optimised –point M coincides

w ith po int O.

The optimising p oint O is the ra ting a t which the

turboc harger is matched, and at which the eng ine

timing a nd c ompress ion ratio a re a djusted.

Optimising point(O)forengine withVIT

The eng ine ca n be fitted w ith VIT fuel pumps , op-tion: 4 35 104, in orde r to improve the S FOC.

The op timising po int O is pla c ed o n line 1 of the loa d

diagra m, and the optimised pow er ca n be from 85 to

100% of point M's pow er, when turboc harger(s)a nd

engine timing are taken into consideration. When

optimising b etw een 93.5% and 100% of po int M's

pow er, overloa d running w ill still be p os s ible (110%

of M).

The op timis ing po int O is to b e plac ed inside th e la y-

out dia gra m. In fac t, the spec ified MCR point M c a n,in spec ial ca ses , be plac ed outside the layout d ia-

gram, but only by exceeding line L1-L2 , a n d o f

co urse , only provided tha t the op timising p oint O is

loc a ted inside the la yout dia gram a nd provided that

the MCR power is not higher than the L1 power.

Load Diagram

Definitions

The loa d d ia gra m, Fig. 2.03, defines the pow er and

speed limits for continuous as well as overload op-

eration of an installed engine having an optimising

point O a nd a sp ec ified MC R point M tha t co nfirms

the ship’s specification.

P oint A is a 100% s peed a nd pow er referenc e point

of the loa d diag ra m, and is d efined a s the point on

the propeller curve (line 1), through the optimising

point O, having the specified MCR power. Normally,

point M is e q ua l to po int A, but in spe cial ca s es , for


402 000 004 198 21 26

2.03

Constantship speedlines

The co nsta nt ship spee d lines

, are shown at thevery top o f Fig. 2.02, indica ting the pow er req uired

at various propeller speeds in order to keep the

same ship speed, provided that the optimum pro -

peller diameter with a n optimum pitch/diameter

vatio is used at any given speed taking into consid -

eration the to ta l propulsion efficiency .

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exam ple if a s haft generator is insta lled, point M ma y

be p la ce d to the right o f point A on line 7.

The s ervice points o f the insta lled eng ine incorpo-

rate the engine power required for ship propulsion

a nd s haft g enerator, if insta lled.

Limits forcontinuousoperation

The co ntinuous service rang e is limited b y four lines :

Line 3 and line 9:

Line 3 represents the maximum acceptable speed

for co ntinuous ope ration, i.e. 105% of A.

If, in s pec ia l ca ses , A is loc a ted to the right o f line

L1-L2, the maximum limit, however, is 105% of L1 .

During tria l co nditions the ma ximum spe ed ma y be

extend ed to 107% of A, s ee line 9.

The a bove limits may in g enera l be extended to

105%, and during trial conditions to 107%, of the

nominal L1 speed of the engine, provided the tor-

siona l vibra tion c ond itions permit.

The ove rspe ed s et-po int is 109% of the s pe ed in A,howe ver, it may b e moved to 109% of the nominal

speed in L1, provide d that torsional vibra tion cond i-

tions permit.

Running a bo ve 100% of the no mina l L1 speed at a

load lower than about 65% specified MCR is, how -

ever, to be avoided for extended periods . Only

pla nts with controlla ble pitch propellers c a n reac h

this light running area.

Line 4:

Repres ents the limit a t w hic h an a mple air supp ly is

available for combustion and imposes a limitation

on the ma ximum co mbina tion of torque and s peed.

Line 5:

Represents the ma ximum mea n effective press ure

level (mep), w hich ca n be a cc epted for continuous

operation.

Line 7:

Represents the ma ximum pow er for co ntinuous

operat ion.

402 000 004 198 21 26


Fig. 2.03b: Engine load diagram for engine with VIT

2.04

178 05 42-7.3

Fig. 2.03a: Engine load diagram for engine without VIT

A 100% re fe re nc e p oint

M S p e cifie d MC R p ointO O pt im is ing p oint

Line 1 P ropeller curve throug h optimising point (i = 3)(eng ine la yout curve)

Line 2 P ropeller curve, fouled hull a nd heavy w ea ther–heavy running (i = 3)

Line 3 S peed limitLine 4 Torq ue/sp ee d limit (i = 2)Line 5 Mea n effec tive pres sure limit (i = 1)

Line 6 P ropeller curve, clea n hull and ca lm wea ther –light running (i = 3), for propeller layout

Line 7 P ow er limit for co ntinuous running (i = 0)Line 8 Overloa d limitLine 9 S peed limit at sea trial

P oint M to b e loc a ted on line 7 (norma lly in point A)

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Limits foroverload operation

The overloa d s ervice rang e is limited a s fo llow s:

Line 8:

Represents the overload operation limitations.

The area b etw een lines 4, 5, 7 and the hea vy da she d

line 8 is a va ila ble for ove rloa d running for limited pe-

riod s only (1 hour pe r 12 hours).

Recommendation

Co ntinuous o pera tion w ithout limita tions is a llow ed

only within the a rea limited by lines 4, 5, 7 a nd 3 o fthe loa d diag ram, except for C P propeller plants

mentioned in the previous s ec tion.

The area be tw een lines 4 a nd 1 is a va ila ble for ope r-

ation in shallow waters, heavy weather and during

a cc eleration, i.e. for non-stea dy operation without

any strict time limitation.

After s ome time in opera tion, the ship’s hull a nd pro-

peller will be fouled, resulting in heavier running of

the prope ller, i.e. the prope ller curve w illmo ve to the

left from line 6 tow a rds line 2, and e xtra po w er is re-quired for propulsion in order to keep the ship’s

speed.

In ca lm wea ther co nditions , the extent of hea vy run-

ning o f the propeller will indica te the ne ed for clean-

ing the hull and possibly polishing the propeller.

Once the s pec ified MCR (a nd the o ptimising po int)

has been chosen, the capacities of the auxiliary

equipment will be adapted to the specified MCR,

a nd the turbocha rger etc. will be ma tched to the op-

timise d pow er, howe ver cons idering the s pec ified

MCR.

If the s pec ified MCR (a nd /or the o ptimis ing p oint) is

to be increa se d later on, this ma y involve a c hang e

of the pump a nd c ooler ca pa cities, retiming o f the

engine, c hang e o f the fuel valve nozzles, a djusting

of the cylinder liner coo ling, a s w ell a s rematc hing of

the turboc harger or even a cha nge to a la rger size of

turbocharger. In some cases i t can also require

la rger dimensions o f the piping sys tems.

It is the refore of utmos t importa nce to c ons ide r, al-

read y at the projec t sta ge , if the spe cifica tion sho uld

be p repa red for a la ter pow er increa se . This is to b eindica ted in item 4 02 010 of the Extent of Delivery.

ExamplesoftheuseoftheLoadDiagram

In the following are some examples illustrating the

flexibility of the layout and load diagrams and the

significa nt influence of the c hoice o f the o ptimising

point O.

The upper diag rams o f the exa mples sho w eng ines

without VIT fuel pumps , i.e. point A = O, the low er

diagrams show engines with VIT fuel pumps forwhich the optimising point O is normally different

from the specified MCR point M as this can improve

the S FOC a t pa rt loa d running.

Example 1 shows how to place the loa d diag ram for

a n eng ine w ithout sha ft ge nerato r co upled to a fixed

pitch propeller.

In example 2 are diagra ms for the sa me c onfigura-

tion, here with the optimising point to the left of the

heavy running propeller curve (2)obtaining an extra

eng ine ma rgin for hea vy running.

As for exa mple 1, example 3 show s the sa me la yout

for an eng ine w ith fixed pitch p ropeller (exa mple 1),

but with a s haft generato r.

Example 4 show s a spe cial ca se with a sha ft genera-

tor. In this c ase the sha ft generato r is c ut off, and the

GenS ets used when the engine runs at specified

MCR. This ma kes it pos sible to c hoos e a sm a ller en-

gine with a low er powe r output.

Example 5 show s diag ra ms for a n engine coupled to

a c ontrolla ble pitch propeller, with or w ithout a s ha ft

generato r, (cons ta nt speed or comb inato r curve

operation).

Example 6 shows where to place the optimising

point for an engine c oupled to a co ntrolla ble pitch

propeller, a nd operating a t cons tant sp eed.

For a p rojec t, the la yout diag ram s how n in Fig. 2.10

ma y be used for co nstruction of the ac tual loa d dia-

gram.


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2.05

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For eng ines w itho ut VIT, the op timis ing po int O will

have the same power as point M and its propeller

curve 1 for engine layout will normally be selected

on the engine service curve 2 (for fouled hull and

heavy weather), as shown in the upper diagram of

Fig. 2.04a.

For eng ines with VIT, the optimising point O and its pro-peller curve 1 will normally be selected on the engine

service curve 2, see the lower diagram of Fig. 2.04a.

P oint A is then found a t the intersec tion betw een pro-peller curve 1 (2)and the consta nt power curve through

M, line 7. In this ca se point A is eq ual to po int M.

402 000 004 198 21 26


2.06

Example1:Normal runningconditions.Enginecoupledtofixedpitchpropeller(FPP)andwithoutshaftgenerator

M Specif ied MCR of engine PointA of loaddiagramis found:S C o nt in uo us s e rvic e ra t in g o f e ng ine Line 1 P ro pe lle r c urve t hro ug h o pt im is ing p oint (O) is

eq ual to line 2O Optimising point of engineA Re fe re nc e po int o f lo a d d ia g ra m Line 7 C ons ta nt po we r line thro ug h s pe cifie d MC R (M)

MP S pe cifie d MC R fo r pro puls io n P o int A Inte rs ec tio n b etw ee n line 1 a nd 7

S P Continuous service rating of propulsion

Fig. 2.04a: Example 1, Layout diagram for normal running

conditions, engine with FPP, without shaft generator Fig. 2.04b: Example 1, Load diagram for normal running

conditions, engine with FPP, without shaft generator

WithVIT

WithoutVIT

178 05 44-0.6

178 39 20-6.0

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Once point A has bee n found in the la yout dia gram ,

the load diagram can be drawn, as shown in Fig.

2.04b and he nce the a ct ua l loa d limitation lines o f the

diesel engine may b e found by using the inclinations

from the co ns truction lines a nd the %-figures s ta ted .

A similar example 2 is shown in Fig. 2.05. In this

case , the optimising point O has been selected

mo re to the left tha n in example 1, ob ta ining a n extra

eng ine ma rgin for hea vy running o pera tion in hea vy

weather conditions. In principle, the light running

ma rgin has b een increas ed for this c a se.


402 000 004 198 21 26

2.07

Example2:Special running conditions. Engine coupledtofixedpitchpropeller (FPP)and withoutshaftgenerator

M Sp ec ified MCR o f eng in e PointA of loaddiagramis found:S C o nt in uo us s e rvic e ra t ing o f e ng ine Line 1 P ro pe lle r c urve t hro ug h o pt im is ing p oint (O)

is eq ual to line 2O Opt imising point o f engine

A Re fe re nc e p oint o f lo a d d ia g ra m Line 7 C ons ta nt po we r line thro ug h s pe cifie d MC R (M)MP S pe cifie d MC R fo r pro puls io n P o int A Inte rs ec tio n b etw ee n line 1 a nd 7

SP Continuous service rating of propulsion

Fig. 2.05a: Example 2, Layout diagram for special running


178 39 23-1.0

WithVIT

WithoutVIT

178 05 46-4.6

Fig. 2.0b: Example 1, Load diagram for special running


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In examp le 3 a s ha ft ge nerato r (S G ) is inst a lled , and

therefore the service po w er of the eng ine also ha s to

incorporate the extra shaft power required for the

sha ft generator’s e lectrica l power prod uction.

In Fig. 2.06a, the engine service curve shown for

heavy running incorporates this extra power.

The optimising point O will b e cho sen on the eng ine

service c urve as show n, but ca n, by an a pproxima-tion, b e loc a ted on c urve 1, throug h point M.

P oint A is then found in the sa me wa y as in exa mple

1, and the loa d diagram ca n be drawn a s s hown in

Fig. 2.06b.

402 000 004 198 21 26


2.08

Example3:Normal running conditions. Engine coupled tofixed pitch propeller (FPP)and withshaftgenerator

M Sp ec ified MCR o f eng in e PointA of load diagramis found:

S C o nt inuo us s e rvic e ra t ing o f e ng in e Lin e 1 P ro pe lle r c urve t hro ug h o pt im is ing p oint (O)

O Optimis ing po int o f e ng ine Line 7 C ons ta nt po we r line thro ug h s pe cified MC R (M)

A= O R efe re nc e p oin t o f lo a d d ia g ra m P o in t A Inte rs ec tio n b etw ee n line 1 a nd 7

MP Spec if ied MCR for propulsion


S G S h a ft g e ne ra t or p ow e r

Fig. 2.06a: Example 3, Layout diagram for normal running


Fig. 2.06b: Example 3, Load diagram for normal running

conditions, engine with FPP, with shaft generator

178 39 25-5.1

178 05 48-8.6

WithVIT

WithoutVIT

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402 000 004 198 21 26

Example4:Special running conditions. Engine coupledtofixed pitch propeller (FPP)and withshaftgenerator

2.09

M Sp ec ified MCR o f eng in e PointA of loaddiagramis found:

S C o nt in uo us s e rvic e ra t ing o f e ng ine Line 1 P ro pe lle r c urve t hro ug h o pt im is ing p oint (O) o rpoint S

O Optimis ing po int o f eng ine P oint A Inte rs ec tio n b etw een line 1 a nd line L1 - L3

A Re fe re nc e po int o f lo a d d ia g ra m P o int M Lo ca te d o n c ons ta nt po we r line 7 thro ug hpo int A. (A = O if the e ng ine is w ithout VIT)and w ith MP's speed.

MP Spec if ied MCR for propulsion


S G S ha ft g ene ra to r

See text on next page.

Fig. 2.07a: Example 4. Layout diagram for special running

conditions, engine with FPP, with shaft generator Fig. 2.07b: Example 4. Load diagram for special running

conditions, engine with FPP, with shaft generator

178 06 35-1.6

178 39 28-0.2

WithVIT

WithoutVIT

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Example4:

Also in this spec ia l cas e, a sha ft generator is in-sta lled b ut, compa red to Exa mple 3, this c a se ha s a

sp ec ified MCR for propulsion, MP , pla ce d a t the top

of the la yout diagra m, se e Fig. 2.07a.

This involves tha t the inten de d s pe c ified MC R of the

eng ine M’ w ill be plac ed o utside the top of the la yout

diagram.

One solution co uld b e to c hoos e a la rger diesel

engine w ith a n extra cylinder, but a nother and

chea per solution is to reduc e the e lec trica l power

production of the shaft generator when running in

the upper propulsion power range.

In choosing the latter solution, the required speci-

fied MCR power can be reduced from point M’ to

po int M a s s how n in Fig. 2.07a. Therefo re, whe n run-ning in the upper propulsion power range, a diesel

generato r has to ta ke over a ll or pa rt of the electrica l

pow er production.

However, such a situation will seldom occur, as

ships are rather infrequently running in the upper

propulsion pow er range.

Point A, having the highest possible power, is

then found a t the intersec tion of line L1-L3 w ith

line 1, see Fig. 2.07a, and the corresponding load

diag ram is d raw n in Fig. 2.07b. P oint M is found

on line 7 at MP’s spe ed.

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2.10

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Fig. 2.08 shows two examples: on the left diagrams

for a n engine without VITfuel pump s (A = O = M), onthe rig ht, for a n engine w ith VITfuel pump s (A= M).

Layoutdiagram- withoutshaftgeneratorIf a c ontrolla ble pitc h propeller (CP P ) is a pplied , the

co mbinato r curve (of the propeller) w ill norma lly b e

selected for loaded ship including sea margin.

The comb inator curve may for a given prope ller spee d

have a given propeller pitch, and this may be heavy run-

ning in heavy weather like for a fixed pitch propeller.

Therefore it is recomme nded to use a light running

comb inator curve a s show n in Fig. 2.08 to ob tain an

increased operation margin of the diesel engine in

hea vy wea ther to the limit indica ted by curves 4 and 5.

Layoutdiagram- withshaftgeneratorThe ha tched area in Fig. 2.08 s hows the recom-

mended spe ed rang e betw een 100% a nd 96.7% of

the specified MCR speed for an engine with shaft

generator running at constant speed.

The service point S ca n be loca ted at any point

within the ha tched a rea.

The proced ure s hown in exa mples 3 a nd 4 for en-

gines w ith FP P c a n also be a pplied here for eng ineswith CP P running w ith a co mbina tor curve.

TheoptimisingpointO for eng ines w ith VITma y becho s en on the p ropeller curve throug h point A = M

with an optimised power from 85 to 100% of the

spe cified MCR a s mentioned before in the s ection

de a ling w ith op timising p oint O.

LoaddiagramTherefore, when the eng ine’s sp ec ified MCR po int

(M) has been chosen including engine margin, sea

margin a nd the pow er for a sha ft generator, if in-sta lled, point M may be us ed a s point A of the loa d

dia gram, which ca n then be draw n.

The po sition of the co mbina tor curve ens ures the

maximum load range within the permitted speed

rang e for engine opera tion, a nd it still lea ves a rea-sonable margin to the limit indicated by curves 4

a nd 5.

Example 6 will give a more detailed description of

how to run co nsta nt speed with a C P propeller.


402 000 004 198 21 26

Example5:

Engine coupledtocontrollablepitchpropeller (CPP)withorwithoutshaftgenerator

M S pec ified MC R of eng ine O Optimis ing point o f eng ine

S C ontinuous s ervic e ra ting o f eng ine A Referenc e po int o f lo ad d ia g ra m

Fig. 2.08: Example 5: Engine with Controllable Pitch Propeller (CPP), with or without shaft generator

2.11

WithVITWithoutVIT 178 39 31-4.1

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Example 6:Engines withVIT fuelpumpsrun-ning atconstantspeed withcontrollablepitch

propeller (CPP)

Fig. 2.09a Constant speed curve through M , nor -

mal and correct location of the optimising po int O

Irres pec tive of w hether the eng ine is o pera ting o n a

prope lle r curve or on a constan t speed curve

through M, the optimising point O must be located

on the propeller curve through the specified MCR

point M or, in spe cial ca se s, to the left of point M.

The rea son is tha t the prope ller curve 1 throug h the

optimising point O is the layout curve of the engine,

a nd the interse ction betwee n curve 1 and the ma xi-mum pow er line 7 throug h point M is e q ua l to 100%

pow er a nd 100%s peed, point Ao f the loa d dia gram

- in this c a se A= M.

In Fig. 2.09a the optimising point O has been placed

co rrectly, and the step-up gea r a nd the sha ft gener-a tor, if insta lled, ma y be sync hronise d o n the con-sta nt speed curve through M.

Fig. 2.09b: Constant speed curve through M ,

wrongposition of optim ising point O

If the engine ha s b een s ervice -optimised in point O

on a c ons ta nt spee d curve throug h point M, then the

sp ec ified MCR point M wo uld be plac ed o utside the

load diagram, and this is not permissible.

Fig. 2.09c: Recommended constant speed run -

ning curve, lower than speed M

In this c a s e it is a ss umed tha t a s ha ft genera tor, if in-sta lled, is sync hronised a t a low er co nsta nt main en-gine speed (for example with speed equal to O or

low er) a t which improved C P propeller efficiency isobtained for part load running.

In this layout example where an improved CP pro-peller efficiency is o bta ined d uring e xtend ed peri-ods of part loa d running, the s tep-up ge a r and the

shaft generator have to be designed for the ap-plied lower co nsta nt engine spe ed.

402 000 004 198 21 26


2.12

Fig. 2.09: Running at constant speed with CPP

Fig. 2.09a: Normal proced ure

Constant speed servicecurve through M

Constant speed servicecurve through M

Fig. 2.09b: Wrong procedure

Logarithmic scales

M: Specified MCRO: Optimised pointA: 100% power and spee d o f loa d

dia g ram (norma lly A= M)

Fig. 2.09c: Rec ommended procedure

Constant speed servicecurve w ith a s peed low erthan M

178 19 69-9.0

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402 000 004 198 21 26

Fig. 2.10: Diagram for actual project

178 06 86-5.1

2.13

Fig. 2.10 contains a layo ut diag ram that ca n be use d for con-struction of the load diagram for an actual project, using the%-figures s ta ted a nd the inclina tions of the lines .

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Specific Fuel OilConsumption

Highefficiency/conventional turbochargers

The high efficiency turbocharger is applied to the

eng ine in the ba sic d es ign w ith the view to ob ta ining

the lowest possible Specific Fuel Oil Consumption

(SFOC)values.

With a conventional turboc harger the a mount of air

req uired for co mbustion purpos es c a n, how ever, be

a djusted to provide a higher exhaust g a s tempera -

ture, if this is nee d ed fo r the exha us t ga s b oiler. The

ma tching of the engine and the turboc harging s ys -

tem is then modified, thus increasing the exhaustga s temperature by 20 °C.

This mo dific a tion will lea d to a 7-8% reduc tion in the

exhaust gas amount, and involve an SFOC penalty

of up to 2 g /B HP h.

So this engine is available in two versions with re-

spec t to the SFOC, s ee Fig. 2.11.

• (A) With hig h effic ienc y turboc ha rger,

(4 59 104)

• (B ) With conventional turbo cha rger,

option: 4 59 107

The ca lculation of the expec ted s pec ific fuel oilc on-sumption (S FOC) can be ca rried out by means of

Fig. 2.12 for fixed pitc h propeller a nd 2.13 for con-trolla ble pitch propeller, co nsta nt sp eed . Through-out the whole loa d a rea the S FOC of the eng ine de-pends on where the optimising point O is chosen.

SFOC atreferenceconditions

The SFOC is ba se d on the referenc e amb ient cond i-tions s ta ted in IS O 3046/1-1986:

1,000 mba r amb ient a ir pres sure

25 °C ambient air temperature

25 °C s ca venge a ir co ola nt tempera ture

a nd is rela ted to a fuel oil w ith a low er ca lorific va lue

of 10,200 kca l/kg (42,700 kJ /kg).

For low er ca lorific va lues a nd for a mbient co nditions

tha t a re different from the ISO reference c ond itions ,

the SFOC w ill be a djusted a cc ording to the co nver-sion factors in the below table provided that the

ma ximum c ombus tion pressure (P ma x) is adjustedto the nominal value (left column), or if the P ma x is

not re-ad jus ted to the nom ina l va lue (righ t column).

WithP ma xadjusted

WithoutP ma xadjusted

P a ra me te r C o nd itio n c ha ng eSFOCchange

SFOCchange

Sc av. a ir coolanttemperature per 10 °C rise + 0 .60% + 0 .41%

Blow er inlettemperature per 10 °C rise

+ 0.20% + 0.71%

Blow er inletpressure per 10 mba r rise - 0.02% - 0.05%

Fuel oil lowe rcalorific value

rise 1%(42, 700 kJ /kg )

-1.00% - 1.00%

With for insta nce 1 °C increas e of the s ca venge a ir

coo la nt temperature , a corresponding 1 °C in -

crease of the s ca venge a ir temperature will occur

and involves an SFOC increase of 0.06% if P ma x is

adjusted.

402 000 004 198 21 26


Fig. 2.11: Example of part load SFOC curves for the two

engine versions

2.14

178 15 22-9.1

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SFOC guarantee

The S FOC gua rantee refers to the ab ove IS O refer-ence conditions and lower calorific value, and is

guaranteed for the power-speed combination in

which the engine is optimised (O) and fulfilling the

IMO NOx e miss ion limita tions .

The SFOC guarantee is given w ith a marg in of 5%.

As SFOC and NOx are interrelated paramaters, an

engine offered without fulfilling the IMO NO x limita -

tions only has a tolerance of 3% of the S FOC.

Without/withVIT fuel pumps

This e ng ine type is in its b a s ic d es ig n fitte d w ith fuel

pump s w itho ut Va ria b le Injec tion Timing (VIT), so

the optimis ing point " O" ha s then to be a t the sp ec i-

fied MCR pow er "M" .

VITfuel pumps c a n, how ever, be fitted a s a n option:

4 35 104, a nd in tha t ca s e they ca n be optimise d be -

tw een 85-100% of the s pec ified MCR, point " M" , as

for the other large MC engine types.

Engines w ith VITfuel pumps c a n be pa rt-loa d o pti-mised between 85-100% (normally at 93.5%)of the

specified MCR.

To fac ilita te the gra phic c a lculation of SFOC w e use

the sa me diagram 1 for guida nce in both ca se s, the

location of the optimising point is the only differ-

ence.

The exa ct S FOC ca lcula ted b y our computer pro-

gra m will in the part loa d a rea from ap prox. 60-95%

give a slightly improved S FOC co mpa red to engines

without VITfuel pumps.

Examples of graphic calculation of SFOC

Diagram 1 in figs. 2.12 and 2.13 valid for fixed pitch

propeller and constant speed, respectively, shows

the reduc tion in SFOC , rela tive to the S FOC a t nomi-

nal ra ted MCR L1 .

The s olid lines a re va lid a t 100, 80 a nd 50% of the

optimised power (O).

The op timising po int O is dra w n into the a bo ve-

mentioned Diag ram 1. A stra ight line a long the

constant mep curves (parallel to L1-L3) is drawn

throug h the o ptimis ing po int O. The line interse c-

tions of the s olid lines a nd the ob liq ue lines indi-ca te the reduc tion in s pec ific fuel oil co nsumpt ion

a t 100%, 80% a nd 50% of the optimis ed pow er,

rela ted to the SFOC sta ted for the nominal MCR

(L1) rating a t the a ctua lly a vaila ble engine version.

The S FOC c urve for an eng ine w ith co nventiona l

turbo cha rger is identica l to that for an e ngine w ith

high efficiency turboc harger, but loc a ted a t 2

g /B HP h highe r leve l.

In Fig. 2.14 an example of the calculated SFOC

curves a re show n on Dia gram 2, va lid for two a l-ternative engine ratings: O 1 = 100% M and

O2 = 85%M.


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402 000 004 198 21 26


Data at nominal MCR (L1): S 50MC -C Da ta of optimis ing point (O)

100% Po we r:

100% Speed :

High efficiency turbo cha rger:

Co nventiona l turboc harger:

127126128

B HPr/min

g/B HP hg/B HP h

P ow er: 100% of (O)

S peed : 100% of (O)

SFOC found:

B HP

r/ming/B HP h

Note: Engines without VITfuel pumps have to be optimised at the specified MCR power 178 88 08-5.0

178 15 92-3.0

Fig. 2.12: SFOC for engine with fixed pitch propeller

178 43 63-9.0

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402 000 004 198 21 26

2.17

Data at nominal MCR (L1): S 50MC -C Da ta of optimis ing point (O)

100% Po we r:

100% Speed :

High efficiency turbo cha rger:Co nventiona l turboc harger:

127

126128

B HPr/min

g/B HP hg/B HP h

P ow er: 100% of (O)

S peed : 100% of (O)

SFOC found:

B HP

r/min

g/B HP h

Note: Engines without VITfuel pumps have to be optimised at the specified MCR power

178 15 91-1.0

Fig. 2.13: SFOC for engine with constant speed 178 43 63-9.0

178 88 08-5.0

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402 000 004 198 21 26


2.18

Data at nominal MCR (L1): 6S 50MC -C Da ta o f o ptimis ing po int (O) O1 O2

100% Po we r:

100% Speed :

High efficiency turbocharger:

12,870127126

B HPr/ming/B HP h

P ower: 100%of O

Speed: 100%of O

SFOC found:

10,680 B HP

114.3 r/min

124.3 g/B HP h

9,080 BHP

108.3 r/min

121.7 g/B HP h

Note: Engines without VITfuel pumps have to be optimised at the specified MCR power

178 15 88-8.0

Fig. 2.14: Example of SFOC for 6S50MC-C with fixed pitch propeller, high efficiency turbocharger and VIT fuel pumps

178 39 37-5.0

178 31 79-0.0

O1: Optimised in M

O2: Optimise d a t 85% of pow er M

P oint 3: is 80% of O2 = 0.80 x 85% of M = 68% M

P oint 4: is 50% of O2 = 0.50 x 85% of M = 42.5% M

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Fuel Consumption at an Arbitrary Load

Once the engine has been optimised in point O,sho w n on this Fig. , the spec ific fuel oilc ons umption

in an arbitrary point S 1, S 2 o r S 3 can be estimated

ba sed on the SFOC in points “1" a nd ”2" .

These S FOC values c a n be ca lcula ted b y using the

g rap hs in Fig . 2.12 for the fixed pitch prope ller curve

I a nd Fig. 2.13 for the co nsta nt spe ed curve II, ob -

ta ining the S FOC in points 1 a nd 2, respe ct ively.

Then the S FOC fo r po int S 1 can be calculated a s an

interpolation b etwe en the S FOC in points “1" a nd

”2" , a nd for point S 3 as a n extra polation.

The S FOC curve through points S 2, to the left ofpoint 1, is s ymme trica l a bo ut point 1, i.e. a t spe ed s

lower than that of point 1, the SFOC will also in-

crease.

The ab ove-mentioned metho d provide s only a n ap-

proximate figure. A more precise indication of the

expected S FOC a t any load ca n be ca lculated b y

using our co mputer progra m. This is a s ervice w hich

is a vaila ble to our cus tomers on reques t.


402 000 004 198 21 26

Fig. 2.15: SFOC at an arbitrary load

178 05 32-0.1

2.19

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EmissionControl

All MC engines are delivered so as to comply with

the IMO speed dependent NOx limit, mea sured a c-

co rding to IS O 8178 Tes t C yc les E2/E3 for Heavy

Duty Dies el Engines.

IMONOx limits, i.e.0-30% NOx reduction

The primary me thod of NOx co ntrol, i.e. eng ine a d -

justment a nd c omponent mod ifica tion to a ffect the

engine combustion proces s directly, enables re-

ductions of up to 30% to b e a chieved.

The S pec ific Fuel Oil Co nsump tion (S FOC) a nd the

NOx a re interrela ted pa ra meters, a nd a n engine of-

fered with a gua ra nteed SFOC a nd also guaranteed

to c om ply with the IMO NOx limitation willbe subject

to a 5% fuel consumption tolerance.

30-50% NOx reduction

Water emulsification of the heavy fuel oil is a well

proven prima ry method . The type o f homog enizer is

either ultrasonic or mechanical, using water fromt he f re s h w a t e r g e n e ra t o r a n d t he w a t e r m is t

ca tche r. The press ure of the homog enised fuel ha s

to be increased to prevent the formation of the

stea m and c a vitation. It may be nec ess a ry to modify

some of the engine components such as the fuel

pumps, camshaft, and the engine control system.

Upto 95-98% NOx reduction

This reduction ca n be ac hieved b y mea ns of s ec-

ondary methods, such as the SCR (Selective Cata -

lytic Reduction), which involves an after-treatment

of the exhaust ga s.

Plants designed ac cording to this method have

been in service since 1990 on four vessels, using

Haldor Topsøe ca talysts and ammonia as the re-

ducing ag ent, urea c an a lso b e used.

The compa ct S CR unit ca n be loc a ted s epa ra tely in

the eng ine room or horizonta lly on top of the engine.

The c ompac t S CR reac tor is mounted before the

turbo cha rger(s ) in order to have the optimum work-

ing tempe rature for the ca ta lyst.

More deta iled informa tion c a n be found in our publi-

cations:

P . 331 Emiss ions Co ntrol, Tw o-stroke Low -spee d

Engines

P. 333 How to deal with Emission Control.

402 000 004 198 21 26


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3. TurbochargerChoice

Turbocharger Types

The MC engines a re des igne d for the applica tion of

eithe r MAN B &W, AB B or Mits ub ishi (MHI) turbo -

cha rgers, a nd are ma tched to comply with the IMO

speed dependent NOx limitations, measured ac -

co rding to IS O 8178 Tes t C yc les E2/E3 for Heavy

Duty Dies el Engines.

The turbocha rger choice is ma de w ith a view to o bta in-

ing the lowes t possible Specific Fuel Oil Consumption

(SFOC) values, i.e. w ith the nominal MCR and the high

efficiency turbocha rgers sta ted in Fig. 3.01a .

The a mount of a ir req uired for the comb ustion ca n,

however be ad justed to provide a higher exhaust

gas temperature, if this is needed for the exhaust

ga s b oiler. In this c a se the co nventiona l turboc har-

ge rs a re to be a pplied , se e Fig. 3.01b. The S FOC is

then ab out 2g/B HPh higher, se e s ection 2.

For other la yout po ints tha n L1 , the size of turbo-

cha rger may be d ifferent, dep end ing on the point at

which the engine is to to be optimised, see the fol-

low ing layout diagra ms.

Figs . 3.02 a nd 3.06 show the a pproxima te limits for

a pplica tion o f the MAN B&W turboc ha rgers, Figs .

3.03, 3.04, 3.07 a nd 3.08 for ABB types TP L and

VTR, res pec tively, a nd Figs . 3.05 a nd 3.09 for MHI

turbochargers.

In order to clean the turbine blad es a nd the noz zle

ring assembly during operation, the exhaust gas in-

let to the turbocha rger(s) is provided with a dry

cleaning sys tem using nut shells a nd a w a ter wa sh-ing system.

As s tanda rd , the eng ine is equ ipped with one

turbo cha rger loc a ted on the a ft end (4 59 124).

The S 50MC-C type engine c a n, as a n option: 4 59

123, be supplied with the turboc harger loc a ted on

the exhaust side.

Tw o turboc ha rgers c a n optiona lly be a pplied , if this

is des ira ble due to s pa ce requirements, o r for other

reasons, option: 4 59 113.


459 100 250 198 21 27

3.01

Fig. 3.01b: Conventional turbochargers, option: 4 59 107

C yl. MAN B &W AB B AB B MHI

4 1 x NA48/S 1 x TP L73-B 12 1 x VTR564D-21 1 x MET53S E

5 1 x NA57/T9 1 x TP L77-B 11 1 x VTR564D-32 1 x MET53S E


7 1 X NA57/T9 1 x TP L80-B 11 1 x VTR714D-32 1 x MET66S E


Fig. 3.01a: High efficiency turboc hargers

C yl. MAN B &W AB B AB B MHI






178 39 04-2.1

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459 100 250 198 21 27


Fig. 3.02: Choice of high efficiency turbochargers, make MAN B&W

3.02

178 39 07-6.1

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459 100 250 198 21 27

3.03

Fig. 3.03: Choice of high efficiency turbochargers, make ABB turbochargers, type TPL

178 39 08-8.1

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459 100 250 198 21 27


3.04

Fig. 3.04: Choice of high efficiency turbochargers, make ABB, type VTR

178 93 11-1.0

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459 100 250 198 21 27

3.05

Fig. 3.05: Choice of high efficiency turbochargers, make MHI

178 39 12-3.1

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459 100 250 198 21 27

3.07

Fig. 3.07: Choice of conventional turbochargers, make ABB, type TPL

178 47 21-1.0

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459 100 250 198 21 27


3.08

178 47 22-3.0

Fig. 3.08: Choice of conventional turbochargers, make ABB, type VTR

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459 100 250 198 21 27

Fig. 3.09: Choice of conventional turbochargers, make MHI

3.09

178 47 23-5.0

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Cut-Off or By-Pass of Exhaust Gas

The exhaust ga s ca n be c ut-off or by-pass ed theturbo cha rgers using either of the follow ing four sys -

tems.

Turbochargercut-outsystemOption:460110

This s ys tem, Fig. 3.10, is to b e inves tiga ted c a se b y

ca se a s its a pplica tion depend s on the la yout of the

turbocharger(s), can be profitably to introduce on

engines with twoturbochargers if the engine is tooperate for long periods a t low loa ds of ab out 50%

of the optimise d po we r or below.

The adva ntag es a re:

Reduced S FOC if one turboc harger is cut-out

• Reduced heat load on essential engine compo-

nents, due to increas ed s ca venge a ir press ure.

This res ults in les s m a intena nce a nd lowe r spa re

parts requirements

• The increa se d sc a venge a ir press ure permits

running without a uxilia ry blowe rs d ow n to

20-30% of specified MCR, instead of 30-40%,

thus saving electrical power.

The s a ving in SFOC a t 50% of optimise d p ow er is

a bo ut 1-2 g/B HP h, while la rger sa vings in S FOC a reobta inable at lower loa ds .

459 100 250 198 21 27


3.10

Fig. 3.10: Position of turbocharger cut-out valves

178 06 93-6.0

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Valve forparticalby-passOption:460117

Va lve for pa rtica l by-pas s o f the exhaust g a s round

the hig h effic ienc y turbo cha rge r(s ), Fig. 3.11, c a n b e

used in order to obtain improved SFOC at part

loa ds. For engine loads ab ove 50% of optimised

pow er, the turboc harger allow s pa rt of the exha ust

ga s to be b y-pas sed round the turbo cha rger, giving

an increased exhaust temperature to the exhaust

ga s b oiler.

At loa ds be low 50% of op t imised power , the

by-pass closes automatically and the turbocharger

wo rks under improved co nditions with high effi-

ciency. Furthermore, the limit for activating the aux-ilia ry blow ers d ecrea ses co rrespondingly.

Totalby-pass foremergencyrunningOption:460119

By-pass of the total amount of exhaust g as round

the turbocharger, Fig. 3.12, is only used for emer-

gency running in case of turbocharger failure.

This e na bles the e ngine to run a t a higher loa d tha n

with a locked rotor under emergency conditions.

The eng ine’s exha ust g a s rec eiver will in this c a se

be fitted w ith a by-pa ss fla nge of the sa me diameter

a s the inlet pipe to the turboc ha rger. The emerg enc y

pipe is the ya rd’s d elivery.


459 100 250 198 21 27

Fig. 3.11: Valve for partical by-pass

3.11

Fig. 3.12: Total by-pass of exhaust for emergency running

178 06 72-1.1 178 06 69-8.0

178 44 67-1.0

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4 ElectricityProduction

Introduction

Next to po w er for propulsion, elec tricity produc tion

is the large s t fuel co nsumer on boa rd. The electricity

is produced by using one or more of the following

types o f ma chinery, either running a lone or in pa rallel:

Auxilia ry dies el g enera ting sets

• Main eng ine driven genera tors

• S team d riven turbog enera tors

• Emergenc y diese l generating sets .

The ma chinery insta lled should be se lected ba sed

on a n econo mica l eva luation of first cos t, operating

costs, and the demand of man-hours for mainte-

nance.

In the following, technical information is given re-

ga rding m a in eng ine d riven g enera tors (P TO) a nd

the auxiliary diesel generating sets produced by

MAN B &W.

The po s sibility of us ing a turbog enera tor driven b y

the steam produced by a n exhaust g as boiler ca n

be evaluated ba sed on the exhaust ga s da ta.

Power Take Off (PTO)

With a ge nerato r co upled to a P ow er Ta ke Off (P TO)

from the main engine, the electricity can be pro -

duced b as ed on the main engine’s low S FOC a nd

use of heavy fuel oil. Several sta nda rdise d P TO sys -

tems are available, see Fig. 4.01 and the designa -

tions on Fig. 4.02:

P TO/RC F

(Pow er Take Off/ Renk Constant Frequency):

G enerator giving c onstant freq uency, b as ed on

mecha nica l-hydraulica l spee d co ntrol.

P TO/C FE

(P ow er Ta ke Off/C ons ta nt Freq uenc y Elec tric a l):

G enerator giving c onstant freq uency, b as ed on

electrical frequency control.

P TO/G C R

(P ow er Ta ke Off/G ea r Cons ta nt Ra tio):

G enera tor co upled to a cons tant ra tio step-up gea r,

used only for engines running a t cons tant s peed.

The DMG /CFE (Direct Mounted Generator/Constant

Frequency Electrical) and the SMG/CFE (Shaft

Mounted Generator/Constant Frequency Electrical)

a re spec ial des igns within the P TO/CFE group in

w hich the g enerato r is c oupled d irectly to the ma in en-gine crankshaft and the intermediate shaft, respec-tively, w ithout a ge a r. The electrica l output of the g en-erato r is co ntrolled by elec trica l frequenc y c ontrol.

Within ea ch P TO sys tem, s everal designs a re a vail-a ble, depending on the pos itioning o f the gea r:

BWI:

G ea r with a vertica l generato r mounted onto the

fore end of the diesel engine, without any con-

nections to the ship structure.

BWII:

A free-sta nding gea r mounted on the tank top

and connected to the fore end of the diesel en -gine, w ith a ve rtica l or horizonta l ge nerato r.

B W III:

A cranksha ft gea r mounted o nto the fore end of

the diese l engine, with a s ide-mounted generato r

without any connections to the ship structure.

On this type of eng ine, spec ia l a ttention ha s to be

pa id to the spa ce req uirements for the BWIII sy s-tem if the turbocharger is located on the exhaust

side.

B W IV:

A free-standing step-up gear connected to the

intermediate shaft, with a horizontal generator.

The mos t popula r of the ge a r bas ed a lterna tives a re

the type des igna ted B W III/RCF for pla nts with a

fixed pitch p ropeller (FP P ) a nd the B W IV/G CR for

plan ts w ith a c ont rolla ble pitch prop eller (C P P ). The

B W III/RCF req uires no s epa rate s ea ting in the s hip

and only little attention from the shipyard with re-

spe ct to a lignment.


485 600 100 198 21 28

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4.02

Alterna tive types a nd la youts of s ha ft g enera tors Des ig n S ea ting Tota l

efficiency (%)

P T

O / R C F

1a 1b B W I/RC F On eng ine(vertical generator)

88-91

2a 2b B W II/RC F On ta nk top 88-91

3a 3b B W III/RC F On eng ine 88-91

4a 4b B W IV/RC F On ta nk top 88-91

P T

O / C F E

5a 5b DMG /C FE On eng ine 84-88

6a 6b S MG /CFE On ta nk top 84-88

P T O / G C R

7 B W I/G C R On eng ine(vertical generator)

92

8 B W II/G C R On ta nk top 92

9 B W III/G C R On eng ine 92

10 B W IV/G CR On ta nk top 92

Fig. 4.01: Types of PTO

178 19 66-3.1

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For further information pleas e refer to o ur publica tion:

P . 364 “Shaf t Genera torsP ow er Ta ke Off

from the Main Engine”

Which is also available at the Internet address:

ww w.ma nbw .dk under “Libraries”.


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Fig. 4.02: Designation of PTO

4.03

Powertake off:BW III S50-C/RCF 700-60

178 39 55-6.0

50: 50 Hz

60: 60 Hz

kWo n g enerator terminals

RCF: Renk consta nt freq uency unitCFE: Elec trica lly freq uency co ntrolled unit

G CR: Step-up gea r with consta nt ratio

Engine type o n which it is a pplied

Layo ut of P TO: S ee Fig. 4.01

Ma ke: MAN B &W

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PTO/RCF

S id e mounte d g ene rat or, BWIII/RC F(Fig. 4.01, Alternative 3)

The P TO/RC F gene rator s ys tems ha ve be en de vel-

oped in close cooperation with the German gear

manufacturer Renk. A complete package solution is

offered, comprising a flexible coupling, a step-up

gear, an epicyclic, variable-ratio gear with built-in

clutch, hydraulic pump a nd moto r, a nd a sta nda rd

ge nerator, se e Fig. 4.03.

For marine engines with controllable pitch propel-

lers running a t cons ta nt engine s peed , the hydraulic

sys tem ca n be d ispens ed w ith, i.e. a P TO/G CR d e-sign is normally use d.

Fig. 4.03 sho w s the principles of the P TO/RCF a r-

rangement. As can be seen, a step-up gear box

(called crankshaft gear) with three gear wheels isbo lted d irectly to the frame b ox of the ma in engine.

The bea rings of the three g ea r w heels a re mounted

in the gea r bo x s o that the w eight of the wheels is not

ca rried by the cranks ha ft. In the fra me box, be tw een

the crankca se a nd the gea r drive, spa ce is a vaila ble

for tuning wheel, c ounterwe ights , a xia l vibration

da mper, etc.

The first gea r w heel is c onnec ted to the c ranksha ft

via a special flexible coupling made in one piece

with a tooth coupling driving the crankshaft gear,

thus is olating it a ga inst torsional a nd axial vibrations.

By m ea ns of a simple a rra ngement, the sha ft in the

crankshaft gearcarrying the first gearwheeland the

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4.04

Fig. 4.03: Power Take Off with Renk constant frequency gear: BW III/RCF, option: 4 85 253

178 00 45-5.0

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Yard d eliveries a re:

1. Co oling wa ter pipes to the built-on lubrica ting oilcooling system, including the valves.

2. Electrica l pow er supply to the lubrica ting oil

sta nd-by pump built on to the RC F unit.

3. Wiring b etwe en the generator and the operator

co ntrol panel in the s witch-bo a rd.

4. An external permanent lubrica ting oil filling-up

connection ca n be esta blished in co nnection w ith

the RCF unit. The sys tem is sho wn in Fig. 4.07 “Lu -

brica ting oil system for RCF g ea r”. The d osa getank and the perta ining p iping a re to b e d elivered

by the ya rd. The size of the dosage ta nk is sta ted in

the ta ble for RCF gea r in “Neces sa ry ca pa cities for

P TO/RC F” (Fig. 4.06).

The neces sa ry preparations to b e ma de o n the en-gine are specified in Figs. 4.05a and 4.05b.

Additionalcapacities required forBWIII/RCF

The ca pa cities s ta ted in the “List of ca pa cities ” forthe main engine in q uestion a re to be increa sed by

the additional ca pac ities for the crankshaft gear and

the RCF ge a r sta ted in Fig. 4.06.

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4.06

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178 05 11-7.0

kW G enerato r

700-60 1200-60 1800-60 2600-60

A 2455 2455 2595 2595

B 776 776 776 776

C 3115 3115 3395 3395

D 3510 3510 3790 3790

F 1826 1946 2066 2176

G 2064 2064 2364 2364

H 2439 2941 3346 4676

S 380 470 500 590

System mass (kg) with generator:

22750 26500 37100 48550

System mass (kg) without generator:20750 23850 32800 43350

The sta ted kW, which is a t gene rato r termina ls, is a va ila ble betw een 70% a nd 100% of the engine spe ed a t

specified MCR

Space requirements for the 2600kWgenerator has to be investigated case by case

Dimens ion H: This is only valid for A. van Ka ick ge nerato r type DS G , enclos ure IP 23,

freq uency = 60 Hz, s peed = 1800 r/min

Fig. 4.04: Space requirement for side mounted generator PTO/RCF type BWlll S50-C/RCF

178 39 57-8.0

4.07

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4.08

Fig. 4 .05a: Engine preparations for PTO 178 40 42-8.0

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4.09

Pos . 1 Specia l face on bedpla te and frame box

P os. 2 Ribs a nd brackets for supporting the face and machined blocks for alignment of gea r or sta tor

housing

P os. 3 Mac hined was hers plac ed on frame box part of face to ensure, that it is f lush with the f

s50mcc

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