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industry have resulted in the need for operators to provide an increasing number of branch connections for new suppliers and new customers, many of which are made by hot tapping. Deregulation in some countries has also made the industry more competitive than ever, so in-service repairs and modifications are more attractive than ever.

9.4.2 Technology trends There is a unique dichotomy that tempers the technology development of the oil and gas pipeline industry. One is the idea that new technology is the means to reduced cost and increased quality. The other is the idea that the risk lies in the unknown and untested. This divergence in thought is present in every industry. As such, the pipeline industry tends to be driven as much by perception and opinion as discovery and scientific facts. In the mid 1980s, several organisations (PRCI, US-DOT, TWI, EWI, etc.) developed reports predicting where the pipeline industry was headed. The common thread of these reports was that they were all accurate at the time of their release yet none were completely accurate in their predictions. Unforeseeable changes and technology advancements altered where industry progressed. The thought process and available information at the time of their authorship, suggested that solid state welding technologies were going to be the dominant practice for pipeline fabrications. The unknown of time was that weld inspection was going to be critically tied to the fitness-for-service (FFS) and engineering critical assessments (ECA). FFS and ECA tended to drive down the acceptable flaw sizes for welded pipelines. The reality became apparent that the fundamental limit of the NDE equipment became the underpinning limitation that controlled a pipelines life prediction and safety factor. Thus, work was underway to improve and optimise the accuracy and limits of NDE technologies. Field NDE companies began to adopt techniques (under the direction of the pipeline owner companies) like automated ultrasonic testing ( AUT). This technology had historically been utilised in the nuclear industry and enabled a tremendous leap in pipeline fabrication understanding and life assessments. Current pipelines construction methods for all but major pipelines projects have not changed much in the past 40 years or so. Many medium to small diameter pipeline are still welded using shielded-metal arc welding (SMAW) and cellulosic-coated electrodes, and inspected using radiography. There is a need to develop or assist companies in implementing some of the emerging pipelines construction technologies for medium to small diameter pipeline projects. For pipeline operations, there is a need to develop innovative pipeline repair technologies. Fibre-reinforced composite repairs are becoming widely used as an alternative to welded full-encirclement steel sleeves, although there are concerns about the long-term performance of these systems. As pipelines become older, the need for repair will only increase as the result of the deterioration of protective coating materials over time and the time-dependant nature of corrosion. Major pipelines in the near future will certainly be constructed using mechanised welding equipment and the completed welds will be inspected using automated ultrasonic testing (AUT) equipment. Future development in pipeline technology include the use of even more productive welding processes that go beyond the optimisation of the GMAW process (e.g. dual torch, tandem torch, dual tandem, etc.) and further development of the AUT process (e.g. phased array transducers). These developments may include the use of hybrid laser/GMAW for all or a portion of the weld or the use of ‘single shot’ welding processes such as friction stir welding. Control of weld quality may be accomplished in the future by advanced process control methods instead of non-destructive examination of completed welds. Nowone seesmanynewweldingautomation techniques beingdeployed to fabricatepipelines. Unfortunately, the predictions of a world where pipeline welds take a few seconds to produce using technologies like flash butt welding, dc butt welding or magnetically impelled arc butt welding has not yet come to pass. New solid-

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Through Optimum Use and Innovation of Welding and Joining Technologies

Improving Global Quality of Life