IIW White Paper

9.11.2 Hot topics In spite of these developments, rail welds continue to present a higher risk of defects and failures compared to parent rail. This risk can now be reduced to some extent by the use, where possible, of longer rail lengths ( up to 120 metres), compared to the previous industry standard of 25 metres. Further improvements in rail welding and joining technology are expected to offer benefits to the rail industry; such improvements may include the development of new or improved rail joining techniques that: Reduce the variation in material characteristics (hardness, microstructure) across the joint, and hence reduce the tendency for weld batter; this will be of particular importance for high strength, heat treated steels such as the hypereutectoid grades that offer substantial improvements in wear and rolling contact fatigue behaviour. Result in lower residual stress levels; and provide reduced welding cycle times, particularly for field welding under traffic conditions. 9.12 Water transmission sector Water Management is a key issue within most Governments’ strategic policies which address the need for sustainable and cost effective delivery of water and waste water services. A sustainable environment is critical to all stakeholders in any country and hence in their national interest. Though access to water is a basic human need and right, it is estimated that some 3 billion people in the world live without access to clean drinking water and sanitation. Welding technology can contribute significantly to addressing critical strategic challenges including drinking water quality, water wastage eg, leaking pipes, environment issues related to effluent discharge and irrigation issues and for industry to meet these challenges in a productive and competitive manner. It is important to identify and develop unique areas of competitive advantage for companies in the Water industry sector e.g. the application of water-jet cutting of degraded reinforced concrete pipe supports to facilitate low cost repairs of corroded pipe. Examples of specific applications and welding technology solutions that countries could analyse, prioritise, develop, demonstrate and disseminate with relevant stakeholders to help meet the challenges and create unique areas of competitive advantage for water companies cover amongst others: Manufacture and construction of mainstream pipelines. Manufacture of pipework and structures in water and waste-water treatment facilities. Manufacture and construction of de-salination plants involving materials such as titanium alloys. The growing use of different materials such as stainless steels, titanium alloys, PVC, polyethylene, polypropylene and polybutylene, ABS and Glass Reinforced Plastic (GRP), as against existing materials such as grey cast iron and steel. Installation and maintenance of water storage liners and floating covers. Repair and maintenance of aging infrastructure. These challenges could be achieved through solutions, amongst others such as: Joining and NDT testing techniques for liners and covers. Avoidance of failures due to poor structural integrity through better design and inspection technology.

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Through Optimum Use and Innovation of Welding and Joining Technologies

Improving Global Quality of Life