mar2012 introduction 2011 block breakdown
DESCRIPTION
Block Breakdown. Credits goes to Newcastle University.TRANSCRIPT
Paul Stott
Hossein Enshaei
February 2011
MAR2012 Engineering applications
Agenda
• Statement of the coursework
• Product breakdown and shipyard layout: Paul Stott
• Process analysis: Hossein Enshaei
• Questions
Block breakdown
Modern shipbuilding divides the ship into blocks.
Block breakdown
• This is a typical block, leaving fabrication ready for erection on the building
berth.
Ship construction processes
Don’t forget that some means is necessary to get the block
to the erection site
Ship construction process
• This is what the erection of blocks in a building dock looks like when it is
very well done.
Block breakdown
How is the block breakdown decided on?
Shipyards strive for the largest practical block at
the erection stage.
Why?........
Block breakdown
0
2
4
6
8
10
12
12
4
8
12
Relative cost of work (manhours) by stage of construction
Block breakdown
Fewer manhours are needed at earlier stages of
production because:
• Supply routes are short
• Access is open and easy
• Crane accessibility is good
• Work can be done “down-hand”
• Staging is unlikely to be required
• Conflict with other work will be minimum
Block definition in shipbuilding
How is the block breakdown for a ship determined?
Constraints and considerations:
• Blocks should as far as possible be self-supporting
• Where possible temporary bracing should be avoided
• Unit breaks should be away from major elements of structure
• Blocks should take account of functional zones
• Maximise the final lift (maximum weight – including outfit)
• Capacity of transport from steel shop to blocking area
• Door dimensions from steel shop
• Workstation dimensions within steel shop
• Blocking area workstation dimensions
• Crane heights
• Other constraints?
Block definition in shipbuilding
How is the block breakdown for a ship determined?
Further considerations:
• Blocks will have a leading edge and a trailing edge
• The leading edge should be relatively rigid – for example close to
a bulkhead: this will ensure maximum stability (i.e. Maintaining
the shape) of the steel until the next block is added
• The trailing edge should be relatively flexible to allow for fairing
• If “green” material is used it should be on the trailing edge
Block definition in shipbuilding
Block definition in shipbuilding
Block definition in shipbuilding
15 20 25 30 35 40
Considering the equipment functional
arrangements define the block breakdown for
both steel and outfit.
Lower zone configuration
Outfit Block Breakdown
As far as possible keep block
breaks clear of equipment
15 20 25 30 35 40
Lower zone configuration
Outfit Block Breakdown
Define the outfit units
installed on steel blocks
prior to erection
As far as possible keep block
breaks clear of outfit unit boundaries
15 20 25 30 35 40
Define the outfit units to
be installed “blue sky”
after block erection
Lower zone configuration
Outfit Block Breakdown
Ensure that the erection sequence
enables straight-lift unit installation
15 20 25 30 35 40
Lower zone configuration
Outfit Block Breakdown
Define accessway and services
route assemblies installed on
steelwork blocks
Ensure that services routes are contained
within steel block boundaries
Steel production
Blocks are the ultimate product of the steel shops.
How are the blocks built up?
Steel manufacture processes• Assembly: the hierarchy of stages
The following diagrams are by kind permission of Malcolm
Bell Associates (Malta)
3D solid model
2 Blocks (P&S)
CAD model exploded at second level
Block assembly analysis
1 Blocks = 4 units + 4 sub assemblies
CAD model Block Breakdown
Unit definition
1 Unit = 5 sub assemblies
Steelwork processes
OU
TF
T IN
STA
LL
AT
ION
• Treatment (shotblasting & priming)
• Cutting / marking
• Forming / shaping
• Welding
• Painting
• Storage, transport and marshalling
Outfit installation
It is essential to productivity and competitiveness that
outfit work and steelwork are integrated as far as
possible and that outfit items are fitted at the earliest
possible stage
Piece parts
Minor assembly
Sub assembly
Unit assembly
Block assembly
Ship
OU
TF
IT IN
STA
LL
AT
ION
Outfit installation
Outfit installation stages by increasing cost
On sub-assembly
On Unit
On Block: open sky
On Block: closed
On Berth: open sky
On Berth: closed
Post-launch
Cost increases
because of more
difficult access and
more difficult working
conditions
Outfit installationIt is essential to productivity and competitiveness that
outfit items are installed in units or assemblies
wherever possible, rather than piece by piece.
Optimum ease of access and least cost in a workshop
environment
Outfit manufacture workshops
• Pipe shop
• Machine shop
• Sheet metal shop
• Electrical shop
• Stores
Don’t forget painting
Shipyard layouts
A layout is on Blackboard for you to look at –
• Yanbu al Bahr (note – this is a large yard and
includes repair as well as newbuild)