Man Bw Technical Paper.pdf

Bulkers – Propulsion Trends in Bulk Carriers

Contents

Introduction.................................................................................................. 5 Market Development..................................................................................... 5 Definition of a bulk carrier......................................................................... 5 Hull design of a bulk carrier...................................................................... 6 Bulk carrier sizes and classes.................................................................. 6 Bulk carrier market.................................................................................. 8 Average Ship Particulars as a Function of Ship Size..................................... 11 Average hull design factor, Fdes. ............................................................. 11 Average design ship speed, Vdes............................................................ 11 Ship speed V as a function of actual draught D...................................... 12 Propulsion Power Demand as a Function of Ship Size.................................. 13 Average bulk carriers............................................................................. 13 Average bulk carriers with ice class notation........................................... 15 Propulsion Power Demand of Average   Bulk Carriers as a Function of Ship Speed................................................... 17 Small and Handysize bulk carriers.......................................................... 17 Handymax and Panamax bulk carriers.................................................... 18 Capesize and VLBC bulk carriers........................................................... 19 Summary.................................................................................................... 20 References................................................................................................. 20

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers

3

Bulkers – Propulsion Trends in Bulk Carriers

Introduction

The purpose of this paper – dealing

Market Development

Bulk carriers, container vessels and

with bulk carrier sizes above 5,000

Definition of a bulk carrier

tankers are the three largest groups of

dwt, and based on an analysis of bulk

In dictionaries, a bulk cargo is defined

vessels within the merchant fleet and,

carriers built/ordered over the last eight

as loose cargo that is loaded directly

therefore, this market segment deserves

years – is to illustrate the latest ship

into a ship’s hold. Bulk cargo is thus a

great attention, see Refs. [1] and [2].

particulars used for modern bulk carri-

shipment such as oil, grain, ores, coal,

ers, and determine their impact on the

cement, etc., or one which is not bun-

The demand for raw materials like coal,

propulsion power demand and main

dled, bottled, or otherwise packed, and

steel, copper, etc., has increased con-

engine choice, using the latest MAN

which is loaded without counting or

siderably since the turn of the millen-

B&W twostroke engine programme as

marking.

nium, especially in consequence of

the basis.

globalisation and the great demand for

A bulk carrier is therefore a ship in which

raw materials in China, owing to the

the cargo is carried in bulk, rather than

economic growth in this large country.

in barrels, bags, containers, etc., and

This means that the Chinese indus-

is usually homogeneous and capable of

try, among others, is absorbing large

being loaded by gravity.

quantities of iron ore and other bulk cargoes.

On the basis of the above definitions,

This consequential higher demand for

drybulk carrier and the wetbulk car-

bulk transports, compared to the bulk

rier, the latter better known as tanker.

there are two types of bulk carriers, the

supply, has caused a dramatic increase in freight rates.

This paper describes the drybulk carrier type, normally just known as bulk

The bulk carrier market, therefore, is

carrier or bulker.

very attractive, which has caused a boost in newbuildings.

Bulk carriers were developed in the 1950s to carry large quantities of

The optimum propeller speed is chang-

nonpacked

ing as well, steadily becoming lower,

grain, coal, etc., in order to reduce

commodities

such

as

because the larger the propeller diam-

transportation costs.

eter that can be used for a ship, the actual propeller speed and pertaining

As mentioned, bulk carriers are one

power requirement will be correspond-

of the three dominating merchant ship

ingly lower, and the lower the propul-

types together with tankers and con-

sion power demand per ton bulk trans-

tainer vessels. Today, bulk carriers

ported.

comprise about one third of the world fleet in tonnage terms.

These factors have an influence on which main engine type should be se-

The world’s, so far, largest bulk carrier

lected/installed as the prime mover,

is the M/V Berge Stahl with 365,000

and also on the size of the bulk carrier

dwt, built in 1986. This huge iron ore

to be built.

bulk carrier measures 343 m in overall length and has a breadth of 63.5

MAN B&W Diesel

m, and scantling draught of 23.0 m.

Bulkers – Propulsion Trends in Bulk Carriers

5

This ship is propelled by an 18,300 kW

requiring double side shells for bulk

However, sometimes the deadweight

MAN B&W twostroke main engine,

carrier newbuildings longer than 150 m.

tonnage used refers to the design

speed of 13.5 knots.

Today, there may be operational or

scantling draught and equals the aver-

commercial reasons for some owners 

age loaded ship in service. Therefore,

Hull design of a bulk carrier

to choose a double skin design, but

the deadweight tonnage that refers to

type 7L90MCE, and has a service ship

draught, which is normally less than the

For several years, the double hull de-

there is no present legislation requiring 

the design draught – which is used

sign has for safety and environmental

a mandatory double hull bulk carrier 

for design of the propulsion system

reasons, been required for new tank-

design. At the 78th session held in May

– is normally lower than the scantling

ers of 5,000 dwt and above. However,

2004 in the “Marine Safety Committee”

draught based deadweight tonnage.

since the 1960s, the standard design

of IMO, the double hull proposal was

for bulk carriers has been a single hull

actually rejected by the majority of the

The sizes of the bulk carriers described

ship with a double bottom, i.e. a hull

members and will probably not be tak-

in this paper are based on the scant-

with single side shells. Therefore, when

en up again in the near future.

ling draught and a seawater density of 1,025 t/m3 and mainly on the single hull

talking about single or double hull, the words ‘side’, ‘skin’ or ‘side shell’ are often used instead of hull.

However, a number of shipyards and

design normally used – as only 5% are

designers are already offering double

of the double hull design.

hull bulk carriers in order to obtain a Studies have shown that the main

more efficient cargo handling as re-

The size of the Panama Canal has for

cause of recorded bulk carrier losses is

quired by some shipowners, especially

almost a century been a decisive fac-

side shell damage, Ref. [3]. In principle,

when transporting e.g. the sticky coal

tor for the dimensions of the so-called

the application of double hull (skin) on

or coke. Furthermore, it seems that

Panamax bulk carriers, see Fig. 1a, but

bulk carriers, therefore, will increase the

the light weight of the double hull ship

might be expected to have a smaller in-

safety and reduce the number of bulk

will be only slightly increased, if at all,

fluence in the future after the intended

carrier losses. Today, about 5% (May

because of the use of thinner steel

opening of an increased third lane.

2007) of the existing bulk carriers are

plates. Of course, more welding nee-

born double-sided.

ded for the double sides will increase

Depending on the deadweight ton-

the manhours and, thereby, the price

nage and hull dimensions, bulk carri-

Besides the increased safety and the

of the ship. Only a minor increase in

ers can be and have been divided into

ability to better withstand collisions,

propulsion power may be expected.

the following main groups or classes.

will give a more efficient cargo handling

Bulk carrier sizes and classes

ping into adjacent groups, see Fig. 1b. 

caused by the absence of hull frames

The deadweight of a ship is the carry-

and brackets protruding into the cargo

ing capacity in metric tons (1,000 kg)

„„

Small

< 10,000 dwt

holds, replaced by the smooth side of

including the weight of bunkers and

„„

Handysize

10,000-35,000 dwt

the inner hull.

other supplies necessary for the ship’s

„„

Handymax

35,000-55,000 dwt

propulsion.

„„

Panamax

60,000-80,000 dwt

„„

Capesize

80,000-200,000 dwt

VLBC

> 200,000 dwt

However, there will be some overlap-

the use of double skinned bulk carriers

For safety reasons, IMO (International Maritime Organisation) and IACS 

The size of a bulk carrier will normally be

„„

(International Association of Classifi-

stated as the maximum possible dead-

(VLBC = Very Large Bulk Carrier)

cation Societies) have brought in new

weight tonnage, which corresponds

regulations for implementation of water

to the fully loaded deadweight at full

In numbers, both the Handymax and

ingress alarms in cargo holds and for-

summer saltwater draught (normally a

Capesize bulk carriers ordered today

ward spaces. They have also discussed

density of 1,025 t/m3), also called the

are dominating and earlier also the

the necessity of introducing regulations

scantling draught of the ship.

Handysize and Panamax, see Fig. 1b.

6

Bulkers – Propulsion Trends in Bulk Carriers

The Panama Canal

Even Ultra Large Handymax bulk carri-

The Panama   Canal                   

ers bigger than about 55,000 dwt and

The lock chambers are 305 m long and 33.5 m wide, and the largest depth of the canal is 12.5-13.7 m. The canal is about 86 km long, and passage takes eight hours.     The canal was inaugurated in 1914 and its dimensions were based on the Titanic (sunk 1912) to be the largest ship of that time.     At present, the canal has two lanes, but a future third lane with an increased lock chamber size (427 m long, 55 m wide and 18.3 m deep) has been decided by the Canal Authority and is intended to open in 2014, at the 100th anniversary of the Canal.

today often called Supramax bulk carriers, with a deadweight tonnage of up to about 60,000 dwt, an overall length of max. 190 m (two Japanese harbours) but now also 200 m and a breadth of 32.2 m (Panama Canal), are now at the project stage. Even though the maximum overall length  limited by the present lock chambers is 

Fig. 1a: The Panama Canal

289.6 m (950 ft), the term Panamaxsize is defined as 32.2/32.3 m (106 ft) breadth,  Bulk carrier classes

225 m overall length, and no more than

Bulk carrier types

Dimensions

Ship size (scantling)

12.0 m draught (39.5 ft) for passage

Small Overall ship length up to

  approx. 115 m

Up to 10,000 dwt

through the canal. The reason for the

Handysize Scantling draught up to

  approx. 10 m

10,000-35,000 dwt

Handymax Overall ship length  (re port facilities in Japan)

  max. 190 m 

35,000-55,000 dwt

Panamax Ship breadth equal to   Overall ship length up to  (re port facilities)  Overall ship length up to   (re canal lock chamber)  Passing ship draught up to

max.:  32.2 / 32.3 m (106 ft)  225 m     289.6 m (950 ft)    12.04 m (39.5 ft)

Capesize Breadth

approx. 4345 m  for 90,000180,000 dwt

80,000-200,000 dwt

VLBC – Very Large Bulk Carrier Overall ship length

  above 300 m

More than 200,000 dwt

smaller ship size (length) used with these ship types is that a large part of the world’s harbours and corresponding facilities are based on the length of 225 m. Panamax bulk carriers continue to grow in cargo capacity as the pressure of

60,000-80,000 dwt

worldwide competition forces shipyards to offer a little bit extra. Thus, a special socalled Kamsarmax Panamax type with an increased overall length of  229 m and 82,000 dwt has been built, and is the largest size able to load at the world’s largest bauxite port, Port Kamsar in Equatorial Guinea.

Examples of special Bulk carrier subclasses „„

Kamsarmax:

~82,000 dwt Panamax with increased LOA = 229 m

The range of the Capesize bulk carri-

(for Port Kamsar in Equatorial Guinea)

ers, i.e. vessels with a deadweight ton-

„„

Dunkirkmax:

~175,000 dwt large Capesize with max. LOA = 289 m and max.

nage higher than 80,000 dwt, has been

B = 45 m (for the French port’s eastern harbour lock at Dunkirk)

increased, as the largest bulk carriers

„„

Newcastlemax: ~185,000 dwt large Capesize with max. beam B = 47 m  are becoming bigger and bigger. Often,

„„

Setouchmax: ~205,000 dwt large Capesize (VLBC) with a low design draught

(for use of the Australian port of Newcastle)



the largest ones are called “Ultra Large Capesize” or just “Very Large Bulk Carrier”

of 16.10 m and max. LOA = 299.9 m

(VLBC). In this discussion, we have de-

(for ports in Setouch Sea in Japan)

cided, in general, to use the latter name

Fig. 1b: Bulk carrier classes

of VLBC for Capesize bulk carriers bigger than 200,000 dwt.

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers

7

Number of s hips in %

Distribution of bulk carrier classes today

B ulk C arrier F leet J a nua ry 2007 - 6, 200 s hips (B ulk c a rriers la rger tha n 5, 000 dwt)

40

The bulk carrier fleet has by far taken over the market for transportation of dry

33.4

35

bulk products, and today the fleet of 28.6

30

bulk carriers larger than 5,000 dwt ac-

25

counts for more than 6,200 ships.

20.5

20 15

As can be seen from Fig. 2a, show-

11.9

ing the distribution of the bulk carrier

10

fleet (larger than 5,000 dwt) in classes,

4.3

5

1.3

0 Small

Handysize

Handymax

Panamax

Capesize

VLBC C la s s es

more than 65% of the bulk carrier fleet – in number of ships – is smaller than 55,000 dwt, with the dominating 33% being Handysize vessels. The Panamax vessels account for 21%, and the large

Fig. 2a: Distribution of bulk carrier classes (number of ships)

ships, Capesize to VLBC, account for 13% of the fleet. When comparing the Total dwt of ships in % 35

total deadweight, instead of the number

B ulk C arrier F leet J anuary 2007 - 350 million dwt (B ulk c arriers larger than 5,000 dwt)

of ships, the distribution of bulk carrier classes changes in favour of the larger

31.7

30

bulk carriers as Panamax and Cape25.7

25

size, see Fig. 2b.

22.8

20

A geneal trend is that the size of bulk

14.5

15

carriers ordered are growing. This means that Handymax bulk carriers are taken

10 4.8

5 0

0.5

Small

Handysize

Handymax

Panamax

Capesize

VLBC C las s es

over for Handysize and Capesize is taken over for Panamax, see the table showing the number of ships in % valid for the present fleet and for ships in order (May 2007).

Fig. 2b: Distribution of bulk carrier classes (deadweight tonnage)

Besides the described main classes

Bulk carrier market

May 2007

for bulk classes, special subclasses

Dry bulk like coal, iron and grain was

Ship class

are often used in order to describe the

initially transported in bags and barrels,

speciality of the ship in question, as for

etc., but owing to the development of

Small

example the abovementioned Kamsar-

the bulk carrier in the 1950s, it is today

max bulk carrier.

transported as nonpacked commodities.

Other examples of subclasses are Dunkirkmax, Newcastlemax and Setouchmax, as stated in Fig.1b.

8

Bulkers – Propulsion Trends in Bulk Carriers

In number of ships Fleet

In order 4%

1%

Handysize

33%

20%

Handymax

29%

37%

Panamax

21%

9%

Capesize

12%

27%

VLBC Total ships

1%

6%

100%

100%

Year of bulk carrier deliveries

(Bulk carriers larger than 5,000 dwt)

Number of ships

1400

Fig. 3 shows the number of bulk carriers

VLBC Capesize

1200 1000

delivered in different periods since the 1950s. More than 18% of the bulk car-

Panamax

rier fleet larger than 5,000 dwt has been

Handymax

delivered within the last five years.

Handysize 800

Smalll

Age of the bulk carrier fleet Fig. 4a shows the age structure of the

600

bulk carrier fleet as of January 2007. 400

Fig. 4b also shows in percent originally delivered ships per five years time pe-

200 0

riod, the number of ships still in operation. Only 25% is more than 25 years 200602 0197

9692

9187

8682

8177

7672

7167

6662

6157

1956

Year of delivery

old, and only 11% is older than 30 years.

Fig. 3: Year of bulk carrier deliveries

Number of ships

Bulk carrier fleet January 2007 (Bulk carriers larger than 5,000 dwt)

1400

VLBC

1200

Capesize Panamax

1000

Handymax

800

Handysize Smalll

600 400 200 0

15

610

1115

1620

2125

2630

3135 3640 4145 4650 51 Age of ships in years

Fig. 4a: Age of the bulk carrier fleet

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers

9

When comparing the number of ships delivered with the age of the bulk carrier fleet today, see Fig. 4b, it can be seen that the lifetime of a bulk carrier is around 2530 years. Thus, above 75% of the ships built 26-

% of delivered ships still in operation

Bulk carrier fleet January 2007 (Bulk carriers larger than 5,000 dwt)

100%

80%

60%

30 years ago are still in service, whereas for ships with an age of 31-35 years,

40%

only about 25% of them are still in service. At the end of April 2007, the order book accounted 1,356 bulk carriers corresponding to 22% of the existing fleet in number and 23% in dwt.

10 Bulkers – Propulsion Trends in Bulk Carriers

20%

0% 15

610

1115

1620

2125

2630

3135

3640

4145

4650

51

Age of ships in years Fig. 4b: Percent of delivered bulk carriers still in operation for a given 5-year period

Average Ship Particulars as a Function of Ship Size On the basis of bulk carriers built or

Average hull design factor, Fdes 3 m /t 2.0 Main ship particulars

contracted in the period 19992007, as reported in the Lloyd’s Register Fair-

LPP B Dscant dwtscant Fdes

1.8

play’s “PC Register”, we have estimated the average ship particulars.

1.6

Average hull design factor, Fdes

1.4

Based on the above statistical material, the average design relationship between the ship particulars of the bulk carriers can be expressed by means of the average hull design factor, Fdes, see

: Length between perpendiculars (m) : Breadth (m) : Scantling draught (m) : Deadweight at scantling draught (t) : Average hull design factor (m3/t) Fdes = LPP x B x Dscant/dwtscant

1.2 1.0 0

200,000 300,000 400,000 dwt Deadweight of ship at scantling draught, dwtscant

100,000

below and Fig. 5. Fig. 5: Average hull design factor of bulk carriers

: ship breadth (m)

Dscant

: scantling draught (m)

300

dwtscant : deadweight tonnage at scantling draught (t) For bulk carrier sizes above 55,000 dwt, the design factor Fdes shown in Fig.

200

100

Based on the above design factor Fdes, and with corresponding accuracy, any missing particular can be found as:

Setouchmax LOA = max 299.9 m Newcastlemax Dunkirkmax

LOA = max 289 m

Kamsarmax

LOA = max 229 m

Alternative Handymax (St. Lawrence Canal)

5 is reasonably exact, whereas the factor is less exact for smaller bulk carriers.

VLBC

B

400 Capesize

perpendiculars (m)

Length between perpendiculars, LPP m

Panamax

: length between

Handymax

LPP

Small

where

Handysize

Fdes = LPP × B × Dscant/dwtscant

(m3/t)

0 0

50,000 100,000 150,000 200,000 250,000 300,000 350,000 400,000 dwt Deadweight of ship at scantling draught, dwtscant

Fig. 6: Average length between perpendiculars

LPP = Fdes × dwtscant/(B × Dscant) m be some exceeding and overlapping of

23.7 m) is used in the narrow Canadian 

the groups, as shown by dotted lines.

St. Lawrence Canal to the Great Lakes.

The three figures show an alternative

Average design ship speed, Vdes

In Figs. 6, 7 and 8, the first three ship

ship design for a 35,000 dwt Handy-

In Fig. 9, the average ship speed Vdes,

particulars are shown as a function of

max bulk carrier with a relatively nar-

used for design of the propulsion sys-

the ship size (dwtscant). The main groups

row ship breadth B, but with a longer

tem and valid for the design draught

of bulk carrier classes normally used

ship length Lpp and higher draught D.

Ddes of the ship, is shown as a function

are also shown. Of course, there may

This narrower ship design (B = max.

of the ship size.

B

=Fdes × dwtcant/(LPP × Dscant) m

Dscant = Fdes × dwtscant/(LPP × B) m dwtscant = LPP × B × Dscant/Fdes t

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers 11

Ship breadth, B m 80

Handysize bulk carriers – is generally

75

higher than or equal to 14.5 knots. The

70 65

only few ship types being built.

45

50

draught D

35 30 25

Depending on the actual deadweight

20

and corresponding displacement, the

15

actual draught D may be lower or higher than the design draught Ddes.

Small

40

Handymax

55

Ship speed V as a function of actual

Capesize

60

VLBC is more doubtful as it is based on

Handysize

trend shown for large Capesize and

VLBC

age ship speed – except for Small and

Panamax

Fig. 9 also shows that today the aver-

B = max 50 m

Newcastlemax

B = max 47 m

Dunkirkmax

B = max 45 m

Kamsarmax

10

Alternative Handymax B = max 23.7 m (St. Lawrence Canal)

5 0

Setouchmax

50,000

0

100,000

150,000

200,000

250,000

300,000

350,000

400,000 dwt

Deadweight of ship at scantling draught, dwt scant

This might – for the same propulsion power – influence the actual ship speed

Fig. 7: Average ship breadth (beam) of bulk carriers

V, as shown in Fig. 10. This figure explains, among other things, why ship-

one case the specified design draught

Scantling draught, Dscant m 25

15

draught.

Small

as for example equal to the scantling

Handysize

specified with a larger design draught,

Panamax

20

Handymax

is low, the design ship speed will be higher than for the same ship type

VLBC

specify different ship speeds. Thus, if in

Capesize

yards for a given ship design/size might

Setouchmax

Ddesign = max 16.1 m

Newcastlemax

10

Dunkirkmax Kamsarmax

5

0

Alternative Handymax (St. Lawrence Canal) 0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000 dwt

Deadweight of ship at scantling draught, dwt scant

Fig. 8: Average scantling draught of bulk carriers

12 Bulkers – Propulsion Trends in Bulk Carriers

carriers built or contracted in the period of 19992007, we have made a power

15

VLBC

16

Capesize

ship particulars and ship speeds for bulk

17

Panamax

Based on the already described average

18 Handymax

(without ice class notation)

Small

Average bulk carriers

Average design ship speed, Vdes knots 19

Handysize

Propulsion Power Demand as a Function of Ship Size

14

prediction calculation (Holtrop & Men-

13

nen’s Method) for such bulk carriers

12

in various sizes from 5,000 dwt up to

11

320,000 dwt.

10

50,000

0

100,000

150,000

200,000 250,000 300,000 350,000 400,000 dwt Deadweight of ship at scantling draught, dwt scant

For all cases, we have assumed a sea margin of 15% and an engine margin of

Fig. 9: Average design ship speed of bulk carriers

10%, i.e. a service rating of 90% SMCR, including 15% sea margin. Change of ship speed, V

Ship speed, V

The average ship particulars of these

knots

knots

+2

bulk carriers are shown in the tables in Figs. 1113. On this basis, and valid for the design draught and design ship speed,

16

we have calculated the specified en-

+1

gine MCR power needed for propulsion. The SMCR power results are also

15

shown in the tables in Figs. 1113,

Design ship speed 14.5 kn

“ship particulars and propulsion SMCR power demand” together with the selected main engine options. These are

0

14

valid, in all cases, for single-screw bulk +/0.5 knots compared to the average

1

Design draught

carriers. The similar results valid for  13

design ship speed are also shown. 60

The average ship particulars used are, 

70

80

90

100

110 120 % Displacement

basically, referring to single hull bulk carriers, but the SMCR power demand 

60

70

80

100

110

120

% Actual draught

found may, as a good guidance, also be used for double hull bulk carriers, by

90

Fig. 10: Ship speed at actual draught for the same propulsion power of bulk carriers

referring to a slightly higher deadweight  tonnage than valid for the double hull design. For example, a 54,000 dwt double

The graph in Fig. 14 shows the above

without ice class notation. The SMCR

hull design could be corresponding to

mentioned table figures of the specified

power curves valid for +/0.5 knot

an about 55,000 dwt single hull design.

engine MCR (SMCR) power needed for

compared to the average design ship

propulsion of an average bulk carrier

speed are also shown.

MAN B&W Diesel

Bulkers – Propulsion Trends in Bulk Carriers 13

Fig. 11: Ship particulars and propulsion SMCR power demand, Small and Handysize bulk carriers

Fig. 12: Ship particulars and propulsion SMCR power demand, Handymax and Panamax bulk carriers

14 Bulkers – Propulsion Trends in Bulk Carriers

Fig. 13: Ship particulars and propulsion SMCR power demand, Capesize and VLBC bulk carriers

Average bulk carriers with ice class

“FinnishSwedish Ice Class Rules”, which

formulae is often in excess of the real

notation

have just been updated. These rules are

power needed for propulsion of the ship.

When sailing in ice with a bulk carrier,

issued by the Finnish Maritime Admin-

Furthermore, it has been concluded

the ship has to be iceclassed for the

istration and apply to all classification

that the formulae can only be used

given operating need of trading in coast-

societies via IACS.

within certain limitations of ship particu-

al states with seasonal or yearround icecovered seas. Besides the safety of the hull structure

lars and therefore Annex 1, listing the Based on the abovedescribed bulk

restrictions to the validity of the formu-

carriers, the minimum power demand

lae, has been added to the rules.

of the ice classed ships, class 1A Super,

under operation in ice, the minimum  1A, 1B and 1C, have been estimated

Ships outside the limitations stipulated

required propulsion power for breaking

for all the bulk carrier classes up to

in Annex 1 have to be model tested

the ice has to be met.

250,000 dwt and drawnin in Fig. 15. In

individually, e.g. Capesize bulk carriers

general, the lowest ice classes, 1B and

longer than the max limitation for ship

1C can – powerwise – always be met.

length stated in Annex 1 (65.0 m < Loa

Depending on the ice class rules and

< 250.0 m).

specific ice classes required for a ship, the minimum ice class required propul-

However, the strongest classes, 1A 

sion power demand may be higher or

Super and 1A, will require a higher 

It is to be expected that many own-

lower than the abovementioned SMCR

propulsion power than the normally

ers may choose to use model tests in

power used for an average bulk carrier

needed average SMCR power for bulk

any case, and independent of the ship

without ice class notation.

carriers without ice class notation.

length, because the model test may

The ice class rules most often used and

Model tests have shown that the power

stalled than what can be calculated us-

referred to for navigation in ice are the

found when using the above new ice class

ing the formulae.

show that a smaller engine can be in-

MAN B&W Diesel

Bulkers – Propulsion Trends in Bulk Carriers 15

SMCR power kW

15,000

Handysize

Small

20,000

Capesize

Panamax

Handymax

25,000

14.7

kn

Setouchmax .5 kn

14

Newcastlemax Dunkirkmax

10,000

Kamsarmax

SMCR power includes: 15% sea margin 10% engine margin

5,000 0

+ 0.5 kn Average design ship speed

VLBC

30,000

0

50,000

100,000

150,000

Alternative Handymax (St. Lawrence Canal ) 200,000 250,000 300,000 350,000 400,000 dwt Deadweight of ship at scantling draught, dwt scant

Fig. 14: Propulsion SMCR power demand of an average bulk carrier

VLBC

SMCR power kW 45,000

Capesize

40,000

Panamax

35,000

Small

20,000 15,000

Handysize

25,000

Handymax

30,000

1A

14.7 1A Super

kn 1B

14.5 kn

1A

Normal SMCR power for average bulk carriers without ice class notation

1C

10,000 1B

5,000 0

1A Super

1C

0

Alternative handymax (St. Lawrence Canal)

100,000 150,000 50,000 200,000 Deadweight of ship at scantling draught, dwt scant

250,000 dwt

Fig. 15: Minimum required propulsion SMCR power demand (CPpropeller) for averagesize bulk carriers with FinnishSwedish ice class notation (for FPpropeller add +11%)

16 Bulkers – Propulsion Trends in Bulk Carriers

Propulsion Power Demand of Average Bulk Carriers as a Function of Ship Speed When the required ship speed is changed,

If to a required ship speed, the needed

Small and Handysize bulk carriers

nominal MCR power for a given main

For Small and Handysize bulk carriers,

engine is too high, it is possible to derate

see Fig. 16, the selection of main en-

the engine, i.e. using an SMCR power

gines is not so distinct as for the large

the required SMCR power will change

lower than the nominal MCR power,

bulk carrier classes. Some owners and

too, as mentioned above, and other

which involves a lower specific fuel con-

yards might prefer fourstroke engines,

main engine options could be selected.

sumption of the engine.

while others prefer and specify twostroke

This trend – with the average ship par-

engines. One owner/yard might prefer 

ticulars and average ship speed as the

Therefore, in some cases it could be of

a 6S42MC7 (6,480 kW at 136 r/min),

basis – is shown in detail in Figs. 1618.

a particular advantage, considering the

and the other, a 7S35ME-B9 (6,090 kW 

See also the description below giving

high fuel price today, to select a higher

at 167 r/min).

the results of the main engine selection

mark number than needed and derate

for the different classes of bulk carriers.

the engine.

For the larger bulk carrier classes, the selection of main engine is, as mentioned, more uniform, see below.

SMCR power kW 12,000 11,000

Handysize

16.0

kn

10,000 9,000

SmalI

8,000 7,000 6,000

3,000 2,000 1,000 0

0

5,000

14.5

kn

13.5 kn 13.0 kn

7L35MC6 6S35MC7 6L35MC6 5L35MC6 7S26MC6 6S26MC6 5S26MC6

kn

n

6S35ME-B9

4,000

15.0

14.0 k

7S35ME-B9

5,000

6S50MC-C8/ME-B8 6S50MC-C7

kn 15.5

5S50MC-C8/ME-B8 5S50MC-C7 6S46MC-C7 Average ship speed 5S50MC6 6S40ME-B9 6S42MC7 5S40ME-B9 5S42MC7

12.5 kn 11.5 kn 11.0 kn

10,000

12.0 kn

15,000 20,000 25,000 30,000 35,000 dwt Deadweight of ship at scantling draught, dwt scant

Fig. 16: Propulsion SMCR power demand of Small and Handysize bulk carriers

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers 17

Handymax and Panamax bulk carriers

The main engines used for Panamax

The main engines most often selected

bulk carriers, see Fig. 17, are mainly

for Handymax bulk carriers, see Fig. 17,

the 5 and 6S60MC/MCC/MEC, with

are the 5 and 6S50MC/MCC/MEB,

the 6S60MC-C8/ME-C8 type being the

with the 6S50ME-B9 type being the

optimum choice for meeting the power

optimum choice for meeting the power

demand for nearly all Panamax bulk

demand of all Handymax bulk carriers

carriers sailing up to 16 knots in service.

sailing up to 15.0 knots in service.

SMCR power kW 18,000 16,000

Panamax Handymax

14,000

6S60MC-C7/ME-C7

8,000

7S50ME-B9 6S60MC6 5S60MC-C8/ME-C8 7S50ME-C8/ME-B8

15.5 kn

12,000 10,000

6S60MC-C8/ME-C8

16.0 kn

7S50MC C7 6S50ME-B9 6S50MC-C8/ME-B8 6S50MC C7

15.0 kn

6S50MC6 5S50MC C7 6S46MC-C7 5S50MC6 6S40ME-B9

14.0 kn

6S50ME-B9 5S60MC6

e 14.5 kn Av era g ed sh ip spe

5S50ME-B9

13.5 kn 13.0 kn

6,000 Kamsarmax 4,000

Alt. Handymax, 14.5 kn (St. Lawrence Canal )

2,000 0

30,000

40,000

50,000

60,000

70,000

80,000 dwt

Deadweight of ship at scantling draught, dwt scant Fig. 17: Propulsion SMCR power demand of Handymax and Panamax bulk carriers

18 Bulkers – Propulsion Trends in Bulk Carriers

Capesize and VLBC bulk carriers

For VLBCs, the 6S70MCC/MEC and

Today, in particular the 6S60MC/MCC/

6S80MC/MCC/MEC types are almost

MEC and 6S70MC/MC-C/ME-C en-

exclusively used as the main engine

gines are used for propulsion of the

today, see Fig. 18. The recently devel-

Capesize bulk carriers, see Fig. 18.

oped S65MEC8 is of course also avail-

The recently developed S65ME-C8 is

able. For the larger VLBCs of the future,

now also available, with 6 or 7 cylinder

the 6 and 7S80MCC/MEC and the

units being most suitable.

6S90MCC/MEC will be most feasible.

SMCR power kW 40,000

35,000

VLBC 6S90MCC8/MEC8 7S80MEC9

30,000 Capesize

n 0k

.

16

25,000

20,000

15,000

10,000

5.5

1 7S70MCC8/MEC8 7S70MCC7/MEC7 7S65MEC8 6S70MCC8/MEC8 6S70MCC7/MEC7 6S65MEC8 6S70MC6 5S70MCC7/MEC7 5S65MEC8 6S60MCC8/MEC8 7S50MEB9 5S60MCC8/MEC8 6S50MEB9

.0

15

kn

kn

6S80MC6

4.5

1

.0

14

ge Avera eed sp ip h s

6S90MCC7/MEC7 7S80MCC8/MEC8 7S80MCC7/MEC7 6S80MEC9 7S80MC6 6S80MCC8/MEC8 6S80MCC7/MEC7

kn

kn n

5k

13.

n 0k 13.

Setouchmax Newcastlemax Dunkirkmax

5,000

0

50,000

100,000 150,000 200,000 250,000 300,000 350,000 400,000 dwt Deadweight of ship at scantling draught, dwt scant

Fig. 18: Propulsion SMCR power demand of Capesize and VLBC bulk carriers

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers 19

Summary

References

The bulk carrier market is an increas-

[1] Propulsion Trends in Container Vessels 

ingly important and attractive transport

MAN Diesel A/S, Copenhagen,

segment which, thanks to the ever in-

Denmark, December 2004

creasing global market volume, is expected to continue to be of great im-

[2] Propulsion Trends in Tankers

portance.

MAN Diesel A/S, Copenhagen, Denmark, July 2007

Since its start in about 1950, the bulk carrier fleet, in terms of deadweight

[3] Side frame failure blamed in recent

tonnage, has increased to about 33%

bulk carrier loss

of the total world fleet operating today.

Lloyd’s List, 18 June 2002, page 3

The demands on the reliability, efficiency and low maintenance costs of the main engines are growing, and only the best twostroke diesel engines can meet these demands. As described, MAN Diesel is able to meet the engine power needs of any size or type of vessel in the modern bulk carrier fleet.

20 Bulkers – Propulsion Trends in Bulk Carriers

MAN B&W Diesel Bulkers – Propulsion Trends in Bulk Carriers 21

Copyright © MAN Diesel & Turbo · Subject to modification in the interest of technical progress.   5510-0007-02ppr Dec. 2010 Printed in Denmark

MAN Diesel & Turbo Teglholmsgade 41  2450 Copenhagen SV, Denmark Phone +45 33 85 11 00 Fax +44 33 85 10 30 [email protected] www.mandieselturbo.com