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LINKING PEOPLE, JOINING NATIONS
and oil and gas industries. Coupled with the overriding interests of these two organisations,
IIW’s qualification of International Welding Engineers (IWE), Welding Specialists (IWS)
and Welding Technologists (IWT), and International Welding Inspection Personnel (IWIP)
accompanied by Welding Inspectors certified through IIW Member Societies, has become
a necessary part of achieving the level of conformity in the construction, design, welding
and repair of maritime shipping. Through the combined efforts of skilled personnel, such
as these, it is possible to ensure that quality is built into the manufacture of a single project
from the very beginning to avoid extensive rework during construction, or when the project
has been completed.
In many instances the costs of repairs and disruption to production
schedules can far outweigh the cost of doing things right in the first place – it
is not possible to inspect quality into welded product after the project has been
completed – at least not without great cost. Non-destructive testing (NDT),
a focus of Commission V
Non-destructive Testing and Quality Assurance of
Welded Products
(C-V), additionally, has been a major partner in ensuring
that structural welding of critical plant and equipment is completed in
accordance with specification, often through the use of conventional or more
sophisticated NDT techniques in the detailed examination of critical welded
joints to achieve compliance.
The megaships of today have been entirely dependent on innovation in construction
techniques and advances in the productivity of welding and its processes. Commensurate
with this, significant evolutionary change has taken place since 1990, notably in the marked
decline in the construction of supertankers, with many of those built in the late 1970s, such
as the
Seawise Giant
(564 650 Dead Weight Tonnage (DWT)) broken up in 2010 and used
for scrap. This does not mean to say that supertankers have finally disappeared from the seas.
Four more prominent Ultra Large Crude Carriers (ULCC), the TI Class supertankers, were
built in Okpu, South Korea in 2002/3 but two of these were converted into sophisticated
floating storage and offloading vessels after extensive alterations in 2009/10.
14
Mindful of
the saying that a supertanker ‘is an accident waiting to happen’ the emphasis in modifying
existing tankers, or building new tankers, since 2000, has been towards vessels with smaller
DWTs of around 90 000 tons that can perform in challenging conditions, such as severe ice
in the Arctic, a change that has increased safety due to double hull construction and thereby
lessening the possibility of oil spills damage to the environment.
15
The latest change in the building of large ships has therefore been a trend towards
the construction of bigger container ships for world trade distribution. An indication of
the extent of this, in recent years, was that almost 12 million tons of newly constructed
container ships were delivered in 2009 with over 85% of this new capacity being built
and welded in South Korea, China and Japan.
16
Many smaller container ships were also