At the ship builders
A look at how ships are made
Session outline
The development of shipping
The physics, design and technology principles
behind ship building
How ships are made
In the beginning…
-
Ships were made from
hollowed out tree
trunks and were called
‘dug outs’
-
As humans made
better tools, they were
able to build better
ships, powering them
through the water with
oars and paddles
The development of shipping
-
Sails allowed for wind power
to propel ships forward
-
Oak was the best wood for
making ships
-
With oak shortages, iron
brackets were used
-
Later more iron was used
and steam engines were
added to drive paddles and
propellers
-
The first iron ship was build
be Brunel in 1839 – The
Great Britain
Why do iron ships float?
Archimedes Principle
“An object in a fluid
experiences an
upward force
equal to the weight
of the fluid
displaced by the
object”
Archimedes in practice:
Explains why iron ships float!
Ball: displaced water weighs less than the ball - SINKS
Hull: displaced water weight is the same as the
hull weight – FLOATS
Hull
Ball
The maths behind the theory:
It’s all about density
Density = Mass
Calculating mass:
In g
Volume
M
Calculating volume: (cm3)
D
Length x Height x Width
V
h
w
l
Golden Rule: If something has a density
of <1g/cm3 it will float in water!
Chemical energy
Heat energy
Fuel
Combustion
Engine
Kinetic energy
Propeller shaft
Oxygen
Work done
HC’s + O2  CO2 + H20
Thrust
Driving ships
forward
The tender and drawings from
the naval architect
Plans are drawn before ships are built by a naval
architect
Plans are taken to the shipping company, where they may
be changed
When both parties agree a test model is built, usually
from wood or wax
Testing the model
Use a piece of equipment known as a ‘towing tank’
Measures the resistance and stability of the model ship
so that the final ship will be seaworthy
Towing tank at Newcastle University
Engines and propellers are also fixed to the model to
decide the best ones for the final ship
Advanced Technology
Points of instability
in red
The mould loft
-
A full sized drawing of the
ship is made in a huge room
called the mould loft
-
Loftsman use a knife to cut
out the lines of the ship
-
Makes templates out of
wood, which are needed to
be cut steel sheets to build
the keel and the hull of the
ship
The time of steel and building of
the keel
Today ships are made of
steel
Ships are often built by
laying the ‘keel’ on a slope,
with a river at the bottom for
launch
Iron becomes iron oxide (rust)
Building of the keel using steel
Cutting of the hull
-
The templates built by the
Loftsman for the hull are
taken to the plater’s shop
-
Platers cut steel plates to
size
-
Two pieces of steel tend to
be cut at any one time
-
Steel plates are painted very
well and evenly to prevent
rust and create a streamline
finish
The steel frame
-
Steel plates for the hull are
fitted to a steel frame
-
The steel frame is made by
frame turners
-
Sometimes bars are made
red hot before being bent
into shape
-
Use long handled hammers
to bent the hot bars
-
Some machines apply
enough pressure to bent
steel frames cold!
Riveting the hull
-
The steel plates and frame
bars need to be joined
together to make the hull
watertight
-
Used to be riveted together
Nowadays we use welding
-
Nowadays plates are
electronically welded
together
-
Hot sparks melt metal strips
and the welders run the
metal into cracks
-
When the metal cools, the
plates are joined together
-
Better than using rivets
because less steel is used
and therefore it costs less to
build your ship!
Fixing the propeller
-
When the hull is ready, the
propeller, rudder and
stabilisers are fitted
-
A hole is cut in the stern and
a propeller shaft put
through, which will
eventually be attached to the
engine
Ship stabilisers
Making the engine
The Launch!
Safety on ships: the load line
Samuel
Plimsoll
Least dense
TF
F
T
S
W
Most dense
WNA
The take home message:
shipping is of great importance to our
everyday lives
Employs 250,000 in the UK
Generates £37 billion to UK economy per year
The fishing industry provides us with a good source of protein for
our diets
Cargo shipping provides us with 95% of the products we use on a
day-to-day basis
Did you know?
British shipping earns the UK economy £162 per second!*
*SeaVision UK