bULK cARRIER PRESENTATION

BULK CARRIER Hull Structural approach

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SUMMARY 1.Introduction 2. Damage to Bulk Carrier 3. Bulk Carriers hull design with IACS UR 4. BV approach

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Introduction

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Introduction ► The Bulk Carrier Market Combined Carriers 151 Ships of 15.1 M. dwt

Capesize Bulk Carrier +80,000dwt 527 ships of 82.5 million dwt Panamax Bulk Carrier 60-80,000dwt 888 ships of 61.5 million dwt

Handymax Bulk Carrier 40-60,000dwt 976 ships of 44.9 million dwt Handysize Bulk Carrier 10-35,000dwt 2,945 ships of 78.7 million dwt

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

Iron ore Coal Grain Salt



Iron ore Coal Grain Bauxite Phosphate



Grain coal Steel prod. Cement Potash Rice Sugar Gypsum Forest prod. Scrap Sulphur

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Introduction ► Type of Loading

Bureau Veritas

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Introduction ► Single side bulk carrier

Bureau Veritas

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Introduction ► Double side bulk carrier

Bureau Veritas

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Damage to Bulk Carriers

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Damage to Bulk Carriers ► Trends of Losses at Sea

2.5

2

Combos

1.5

dwt

Bulkers 1

Tankers

0.5

0 1970

1974

1978

1982

1986

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1990

1994

1998

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Damage to Bulk Carriers ► Bulk carrier losses

B U L K C A R R IE R S L O S T

L O S S O F L IV E S

25

200 180

No. live s lost

160

15

10

5

140 120 100 80 60 40 20

0

Ye a rs

2001

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

1990

2001

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

0

1990

No. ve sse ls lost

20

Ye a rs

A crew safety problem Source: Intercargo Bureau Veritas

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Damage to Bulk Carriers Primary causes of casualties Bulk carriers

80%

Considering data from 1999 to 2000, primary causes of fatalities are:

70%

60%

50%

1. Hull damages 2. Navigation error 3. Fire and explosion 4. Machinery failures

40%

Machinery failure navigation error

30%

fire and explosion 20%

hull failure 10%

35%

miscellaneous

0%

10%

5%

0%

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miscellaneous

15%

hull failure

Oil tankers

fire and explosion

20%

navigation error

25%

Machinery failure

30%

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Damage to Bulk Carriers

frequency of incidents per ship year

Mini 3.00E-03

Handysize Handymax

2.50E-03

Panamax

2.00E-03

Cape size

1.50E-03 1.00E-03 5.00E-04

0.00E+00 Hatchcover

Pipes& valves

Side Shell

Side Shell Bottom Shell (Collision)

Deck

Side Shell Penetration

categories of incidents

Bureau Veritas

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Damage to Bulk Carriers ► Type of Damages

• cracking at hatch corners; • plate panel buckling of cross deck strips and stiffening structure; • cracking of hatch coamings;

• cracking at the intersection of the inner bottom plating and the hopper/stool platings • grab and bulldozer damage to the main frames lower brackets

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Damage to Bulk Carriers ► Type of Damages

• cracking at main frame bracket toes • corrosion within topside tanks, of the tranverse bulkheads, the frames and brackets

Bureau Veritas

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Damage to Bulk Carriers ► Type of Damages

Bureau Veritas

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Damage to Bulk Carriers ► Type of Damages

Bureau Veritas

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Damage to Bulk Carriers ► Type of Damages – Hatch Covers

• 1 or 2 case of missing/lost hatch cover per year (excluding ships which sunk) • N°1 hatch cover ten times more likely to be damaged than hatches from amidships to aft

Bureau Veritas

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Damage to Bulk Carriers ► Rules into force - Conclusion

• IMO (SOLAS Ch. XII) : Safety • IACS Requirements : strength of hull and stability

 regulation URS 12,17,18,20,21,25,27… • BV Rules April 2005 or CSR rules

 includes IACS and IMO requiremetns

Bureau Veritas

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Bulk Carriers Hull design IACS UR requirements

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Bulk Carriers Hull design with IACS UR requirement ► IACS Rules for New Bulk

UR S1/1 A - Requirements for loading conditions, loading manuals, loading instruments and loading sequences

0,125 h

UR S12 - Requirements forSIDE STRUCTURES in single side skin (following UR Z11) Bulk Carrier

h 0,125 h

UR S17 - LONGITUDINAL STRENGTH of Hull girder in flooded condition

UR S18 - Scantlings requirements for Transverse corrugated

watertight bulkheads in flooded condition for each hold (only single side skin B/C following URZ11) Bureau Veritas

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Bulk Carriers Hull design with IACS UR requirement ► IACS Rules for New Bulk

UR S20 - Scantlings requirements for Double Bottom in flooded condition for each hold (only single side skin B/C following URZ11)

UR S21 - Strength requirements for Hatch Covers and coamings located forward of 0.25 L from the fore perpendicular

Ex UR S24 replaced by SOLAS Ch. XII Reg. 12 and 13 (Resolution MSC 134 (76) and MSC 145 (77)) + UI SC 179/180 -Cargo hold, ballast and dry space water level detectors (REG. 12) – (regardless date of construction) -Dewatering of forward spaces of B/C (REG. 13) – (regardless date of construction)

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Bulk Carriers Hull design with IACS UR requirement ► IACS Rules for New Bulk

UR S25

UR S26

- harmonized notations and corresponding design loading conditions including Mass Curves definition

- Strength and securing of SMALL HATCHES on the exposed fore deck

UR S27

UR S28

- Strength requirements for fore deck fittings (Ventilator and air pipes) and equipments (Windlasses)

- Requirements for the fitting of a FORECASTLE

Bureau Veritas

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Bulk Carriers Hull design with IACS UR requirement ► UR S1 and UR S1A : Loading Instrument and Manual

• Loading Instrument • all existing bulk carriers of both single and double side skin construction

• Loading Manual • all existing single side skin bulk carriers • all new bulk carriers, ore carriers and combination carriers

•

includes Loading sequences for single side skin bulk carriers >= 150m built before 1/7/98

• includes Loading sequences for all new bulk carriers >= 150m built after 1/7/98

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Bulk Carriers Hull design with IACS UR requirement ► UR S12 : Side Structures

• Minimum thickness of frame web :

0,125 h

h 0,125 h

t w,min = C(7 + 0.03 L) (+ 15% in foremost hold)

• Minimum thickness of side shell : • Requirements for construction of upper and lower brackets

• Welding requirements • No combined load « cargo + sea water » considered

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Bulk Carriers Hull design with IACS UR requirement ► UR S17 : Longitudinal Strength of Hull Girder in Flooded Condition

• Flooding of any hold in any loading condition : •

equilibrium calculation: MSW and FSW in flooded condition

•

calculation of

 under MSW + 0.8 MW

 under FSW + 0.8 FW

Typical reinforcements induced by UR S17 •  >  adm



increase of section modulus in midship area (increase of deck thickness)

•  >  adm



increase of side shell thickness in way of transverse bulkhead Bureau Veritas

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Bulk Carriers Hull design with IACS UR requirement ► UR S18 : Corrugated transverse watertight bulkhead

• Calculation of pressure induced by flooding (design load= cargo + sea water):  bending moment and shear force acting on the bulkhead

• Checking of section modulus of the corrugation under the bending moment (taking into account

gussets or shedder plates)

Gusset Plates

Bureau Veritas

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Bulk Carriers Hull design with IACS UR requirement ► UR S18 : Corrugated transverse watertight bulkhead

• Checking of shear stress in web of the corrugation with requirement for shear buckling • Strength of plate under local pressure • Requirements for construction of upper and lower stools and alignment conditions ► Typical reinforcements induced by UR S18

• Increase thickness of flange / web of corrugation • Gusset or shedder plates

Bureau Veritas

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Bulk Carriers Hull design with IACS UR requirement ► UR S20 : Allowable hold loading

• Calculation of shear strength of the double bottom to obtain the allowable hold loading considering hold flooding

• Sum of shear areas of floors and girders taking into account holes if any ► Typical reinforcements induced by UR S20

• Increase thickness of flange / girders at their ends • Add partial floors / girders

• Remove holes

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Bulk Carriers Hull design with IACS UR requirement ► UR S21 : Hatch Cover

• Design load based on green sea on deck • Only hatch covers located forward of 0.25 L from the fore perpendicular • Direct calculation of primary members (with effective width for compression flanges) under pressure

• Allowable stresses: a a

= 0.8 F (yieldstress) = 0.45 F

Bureau Veritas

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Bulk Carriers Hull design with IACS UR requirement ► UR S25 : Harmonized notations and corresponding design Loading

conditions for B/C • Definition of notation • BC-A dens>1t/m3, + specified empty hold at maximum draught, + BC-B conditions. • BC-B dens>1t/m3, + no empty hold, + BC-C conditions. • BC-C dens