Improving Global Quality of Life
Improving Global Quality of Life
Improving Global Quality of Life
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9.3.2 Hot Topics<br />
The following issues and technical areas are considered to be the key topics for future technical developments<br />
<strong>of</strong> welding, joining and allied technologies:<br />
Deepwater exploration and production<br />
Whole-life performance <strong>of</strong> steel risers.<br />
New materials for risers, both ferrous and non-ferrous.<br />
Inspection <strong>of</strong> risers.<br />
Dissimilar materials joint performance.<br />
Pipeline wall thickness, laying and welding.<br />
Materials challenges for exploration in arctic region and transportation <strong>of</strong> fuels<br />
High-productivity welding <strong>of</strong> pipelines.<br />
Manufacturing technologies for tankers and gas carriers.<br />
On-line repair techniques <strong>of</strong> pipelines.<br />
New design concepts for high-productivity pipe-lay.<br />
Advanced inspection techniques <strong>of</strong> transportation structures (pipelines; liquid natural gas carriers<br />
and tankers).<br />
Corrosion mitigation technique developments (coatings etc).<br />
<strong>Life</strong> extension <strong>of</strong> ageing assets.<br />
Training, qualification and certification <strong>of</strong> joining and allied human resources in emerging markets.<br />
9.3.3 Hyperbaric welding<br />
Hyperbaric welding is the process <strong>of</strong> welding at elevated pressures, normally underwater. It can either take<br />
place wet in the water itself or dry inside a specially constructed positive pressure enclosure and hence a dry<br />
environment. It is predominantly referred to as“hyperbaric welding” when used in a dry environment, and<br />
«underwater welding» when in a wet environment. The applications <strong>of</strong> hyperbaric welding are diverse – it is<br />
<strong>of</strong>ten used to repair ships, <strong>of</strong>fshore oil platforms, and pipelines. Steel is the most common material welded.<br />
The demand for highly sophisticated underwater procedures and technologies is increasing, driven by deep<br />
sea oil and gas development and by marine infrastructure development and repair around the world.<br />
Dry hyperbaric welding is used in preference to wet underwater welding when high quality welds are<br />
required because <strong>of</strong> the increased control over conditions which can be exerted, such as through application<br />
<strong>of</strong> prior and post weld heat treatments. This improved environmental control leads directly to improved<br />
process performance and a generally much higher quality weld than a comparative wet weld. Thus, when<br />
a very high quality weld is required, dry hyperbaric welding is normally utilised. Research into using dry<br />
hyperbaric welding at depths <strong>of</strong> up to 1,000 metres (3,300 ft) is ongoing. In general, assuring the integrity<br />
<strong>of</strong> underwater welds can be difficult (but is possible using various nondestructive testing applications),<br />
especially for wet underwater welds, because defects are difficult to detect if the defects are beneath the<br />
surface <strong>of</strong> the weld.<br />
The majority <strong>of</strong> work performed by an average welder-diver does not involve the welding operation itself,<br />
but rather executing the tasks that lead up to and follow the actual welding activities. Except under special<br />
circumstances, a welder-diver in most cases must possess both certified welder skills and commercial diving skills.<br />
106 <strong>Improving</strong> <strong>Global</strong> <strong>Quality</strong> <strong>of</strong> <strong>Life</strong> Through Optimum Use and Innovation <strong>of</strong> Welding and Joining Technologies