Cargo Holds
Cargo hold coatings must possess not only good anticorrosive
properties, but also a number of other important properties,
including chemical and abrasion resistance against the vast
array of modern bulk cargoes. Future operating conditions
and the type of cargoes to be carried must therefore be taken
into careful consideration when selecting the optimum coating
system.
Some bulk cargoes are extremely abrasive because they are
of hard material. Scrap iron and iron ore pellets are typical
examples which have high abrasive impact on bulkheads and
tanktops. Coal may be a very corrosive cargo if sulphuric
acid is developed during transportation. Also the temperature
of a coal cargo may be very high - either because temperature
is high during loading or because the coal generates heat
due to oxidation. Consequently, abrasion resistance, chemical
resistance and heat resistance are important properties which
have to be built into the coating system.
Futher requirements include certificate for the transportation
of grain as it is important that the coating system does not
exude substances harmful to the health. The coating must be
easy to clean, and cleaning is most effectively controlled
if the cargo hold is coated in a light colour. Finally, loading,
discharging and mooring operations may cause extensive deformation
of the steel, and consequently the coating system must also
have optimum adhesion and flexibility in order to provide
the corrosion protection required.
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