Steel versus Polymers
v. Birgit Kjærside Storm
Plast Center Danmark
Polymers in offshore industry
Which polymers can be used in the off shore
industry?
It depends on for which application it shall be
used
There are advantages and there are
disadvantages for using polymers in the off
shore industry
Advantages of polymers
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Low density
Corrosion resistance against seawater
Isolators for electricity and heat
Less maintenance compared with steel
Formability
Possibility to make composites with high
strength/weight ratio
Disadvantages
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Flammability
Low strength and stiffness compared with
steel
Risk for permeability of gas
Risk for static electricity
Temperature interval
Composites
Composites are obvious to regard as materials
because of
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Strength/weight ratio
Corrosion resistance against seawater and
oil/gas
Thermal stability in a high interval
Composites
A composite is a material, which contains of at
least two phases
The most used composites for constructions
are glass fibre and carbonfibre reinforced
composites with a matrix of unsaturated
polyester or epoxy
Composites
Composites of carbon fibre reinforced epoxy
can obtain a strength and a stiffness which is
comparable with the strength/stiffness of
steel and with a density about 1,5 g/cm3
Compsites with epoxy have a good chemical
resistance against seawater and oil
Polymers
Many types of polymers are used in the off
shore industry
Thermoplastics are used for piping, in pumps,
in valves, as gaskets and many other
applications
Steel and polymers
Polymers has many advantages when they can
be compared with steel
Most important are
¾ Low density
¾ Corrosion resistance
Steel and polymers
There are disadvantages also
Some of them are
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Permeability for gas
Water content in polymers
Burnability
Steel and polymers
Shall we use steel or polymers?
The answer is not so simple, because in each
case it will depend on the application
But we shall not select steel because we
normally do that
Steel versus polymers
We shall use polymers and polymerbased
composites where their advantages can be
used
We can use composites for many applications,
but we need to think of good protection of the
surface for low permeability and other
disadvantages
Steel versus polymers
For using steel we have good experience
The maintenance of steel is welknown
For polymers/composites we have not the
same experience and the possible problems
with maintenance can be barrieres for
selecting them
Polymers/composites
In the future a lot of the disadvantages for
using polymers/composites in the off shore
industry will be solved
And then we will for many application – much
more than today – see the use of
polymers/composites for off shore
constructions – the off shore wind turbines
are good examples of use of composites
Thank you for your attention