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© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved.
<Title of Presentation>
By: <Author Name>, <Organization>
<Date>
<Title of Presentation> By: <Author Name>, <Organization>
<Date>
17th INTERNATIONAL CONFERENCE & EXHIBITION
ON LIQUEFIED NATURAL GAS (LNG 17)
DESIGN OF THE EVOLUTIONARY LNG
CARRIER “SAYAENDO”
By
Koichi Sato
Mitsubishi Heavy Industries (MHI), Ltd. Japan
&
Henry Chung
Lloyd’s Register Group Limited (LR)
Yokohama Design Support Office, Japan
18 April 2013
17th INTERNATIONAL CONFERENCE & EXHIBITION ON
LIQUEFIED NATURAL GAS (LNG 17)
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 1
INTRODUCTION
1. MHI has developed a next-generation spherical tank LNG
carrier with a continuous tank cover, nicknamed
SAYAENDO, meaning “peas in a pod”.
2. SAYAENDO has many advantages, such as lighter steel
weight, improved fuel consumption, better terminal
compatibility, better maintainability.
3. This presentation
introduces the design of
SAYAENDO and the
state-of-the-art
engineering verification
methodologies applied.
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 2
CONTENTS OF PRESENTATION
1. Design concept of SAYAENDO
(comparison with conventional)
2. Technical key points
3. Advanced Structural Analysis
4. Application to 155 km3 LNGC
5. Application to cold region
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 3
MHI SPHERICAL LNGC DESIGN HISTORY
1. Forty-two LNG carriers delivered since 1983.
2. Epoch making “2nd generation LNGC" with a lower BOR
with a forcing vaporizer.
3. Continuous developement with 3rd generation (137km3)
and 4th generation (147km3)
1st
2nd 3rd
4th
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 4
SAYAENDO vs CONVENTIONAL (1)
Reduction of steel weight by 5-10%,
for ship over 147 k-m3 due to new
structural concept.
h
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 5
SAYAENDO vs CONVENTIONAL (2)
Increase of height of tank cover
Increase of steel weight of non hull girder member
Increased steel weight of cover
(increased steel weight of non-strength member)
Main hull(strength member)
Tank cover(non strength member)
stretched
125 k-m3 LNGC 155 k-m3 LNGC (with stretched tank)
Increased steel weight of cover
(increased steel weight of
non-hull girder member)
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 6
OVERALL CONFIGRATION OF SAYAENDO
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 7
KEY POINTS IN DEVELOPMENT
1. Structural design and assessment
Longitudinal strength assessment
Detail connection design
Tank cover and main hull connections including
fore and aft ends
Interaction between cargo tank and hull
Fatigue assessment for structural detail
2. Aerodynamic assessment with wind-tunnel tests
3. Manoeuvrability simulation and mooring analysis
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 8
ADVANCED ANALYSIS BY MHI-DILAM (1)
1. Advanced structural analysis by MHI-DILAM carried out
for yield, buckling and fatigue criteria.
2. Yield and buckling strength confirmed acceptable
against maximum load in ship lifetime.
Higher stress
Lower stress
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 9
ADVANCED ANALYSIS BY MHI-DILAM (2)
1. 50 years of design fatigue life fit for world-wide LNG
trading has been confirmed.
2. Reduced hull girder stress has favourable effect in
SAYAENDO, allowing possibility of efficient structural
design to achieve the given fatigue design specification.
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 10
ADVANCED ANALYSIS BY MHI-DILAM (3)
1. Comparison of hull girder stress (Deck and Bottom)
2. Comparison of hull / tank interaction force
Upp. Dk.
Tank
connection
Neutral axis
Upp. Dk.
Neutral axis
147km3 LNGC Conventional moss type 155km3 LNGC SAYAENDO type
skirt
connection
Tank
connection
skirt
connection
Point-A
Deck stress
Point-B
Bottom
stress
Point-B
Bottom
stress
Point-C
Tank stress by
hull deflection
Point-C
Tank stress by
hull deflection
Point-A
Deck stress
0
20
40
60
80
100
[Point-A] Deckstress
[Point-B] Bottomstress
[Point-C] Tankstress by hull
deflection
147 LNGC
155 SAYAENDO
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 11
THE 155k-m3 SAYAENDO (1)
Conventional 147 k-m3 Sayaendo 155 k-m3
Tank capacity Approx. 147,200 m3 Approx. 155,300 m3
(stretched)
Loa 288 m 288 m
B (mld.) 49.0 m 48.94 m
D (mld.) 26.8 m 26.0 m
Speed Approx. 19.5 knot Approx. 19.5 knot
Main Propulsion
Plant
Conventional
steam turbine
UST
(Ultra steam turbine)
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 12
THE 155k-m3 SAYAENDO (2)
1. MHI-UST (Ultra Steam Turbine plant), a new turbine plant
2. 25% reduction in fuel consumption compared with
conventional ships
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 13
ICE BREAKING SAYAENDO
1. Independent tank system: tolerant to local ice impact
2. Overall hull girder strength: highly effective in resisting
global ice impact loads.
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 14
CONCLUSIONS
1. State-of-the-art engineering verification methodologies
by the shipyard and the classification society were
applied to validate the new design to meet the stringent
technical, regulatory and safety requirements of the LNG
shipping industry.
2. As a product, SAYAENDO has the following advantage.
New structural concept offering more rigidity with less light weight.
Compact design, especially in ship’s depth.
Lower maintenance cost, due to omission of flying passage.
Suitability for navigation in cold region.
© 2012 MITSUBISHI HEAVY INDUSTRIES, LTD. All Rights Reserved. 15
Lloyd’s Register: Marine
Notable Aspects of Class Consideration
Class notation for standard ship:
Structural Consideration focusing on the Tank Cover:
Design Verification using LR’s ShipRight Procedures
Safety of overall ship arrangement in respect of:
© 2012 Lloyd’s Register Group Limited. All Rights Reserved. 16
✠100A1 Liquefied Gas Carrier, Ship Type 2G, Methane (LNG) in
independent spherical tanks type B, Maximum vapour pressure 0.25bar,
Minimum temperature –163C, ShipRight(SDA, FDA plus(50,WW), CM,
ACS(B)), *IWS, LI, ✠LMC, UMS, ICC with the descriptive notes
ShipRight(SCM, BWMP(T)), ETA.
(1) Tank Cover as a Protective Structure for the Cargo Tanks
(2) Tank Cover as a Primary Hull Strength Member
(1) LNG cargo manifold system
(2) Arrangement of the cargo machinery room
Lloyd’s Register: Marine
Typical Fatigue Checking Locations on Tank Cover
Upper and Lower Corners
iwo Manifold Recess
Aft Scarphing Structure
Forward Scarphing
Structure
Opening iwo Cargo
Tank Dome
Knuckles iwo
Cofferdam BHD
Screening
Fine mesh hotspot stress
© 2012 Lloyd’s Register Group Limited. All Rights Reserved. 17
Lloyd’s Register: Marine
Typical LNG Trading Pattern for ShipRight(FDA) notation
Trading Routes
North Sea – NE USA
North Africa – NE USA
North Africa – Gulf of Mexico
North Africa – N Europe
Middle East – NE Asia
NW Australia – NE Asia
SE Asia – NE Asia
© 2012 Lloyd’s Register Group Limited. All Rights Reserved. 18