Search academic texts

Information × Registration Number 0210U003601, 0107U004951 , R & D reports Title Raise of an operational resource of pipelines by application of the laser and combined welding technologies of pipe steel. popup.stage_title Head Shelyagin Vladimir Dmitrievich, Кандидат технічних наук Registration Date 11-02-2010 Organization E.O.Paton Electric Welding Institute of the National of Sciences of Ukraine popup.description2 The aim of the work was the development of welding technology, which allows to increase service life of pipe butt joints of high strength steels by using methods of single-or multi-pass laser and hybrid laser-arc welding in a narrow breaker using a wire electrode materials. It is established that to improve the life extension of pipelines to create a useful new way of toggling weld joints, which will reduce the grain size in cast metal and HAZ by reducing the energy per unit length, while maintaining (or improving) performance than the existing method of welding with coated electrodes. The rate of intercrystalline corrosion will be reduced, thus increase the life of cooked so the pipeline. Achieving this is possible with the application of technology multipass laser or laser-arc welding. To conduct technological research on laser and hybrid laser-arc welding of pipe steels have been designed and constructed two laboratory stand to make use of radiation of CO2 and Nd: YAG-laser. We establish conditions for appropriate use and technological parameters of single-i multipass laser and hybrid welding of pipe steels. The optimal form of cutting edges, providing high quality joints and helps to ensure a return roller. Laser welding of orbital sutures advisable to double "on podem" in the sectors to 200 ?, and hybrid - twice "the trigger" in the same sectors. In both cases, the speed of the process should not change by sector, with the angular size of 30 ? to 60 ?. In places the docking of the two welds is possible to apply power control of laser radiation. To resolve the flowing liquid metal from the weld pool during welding of horizontal seams appropriate to reduce its size, for example, by using pulse modulation of radiation, increasing the number of passes during multipass welding, weld seam root zaplavleniem laser with narrow cutting edges of welded hybrid method. In the latter case it is advisable to use the electrode wire of small diameter (up to ?1, 0 mm) and low values of welding current. To eliminate such characteristic for multi-pass laser welding defects as nesplavleniya weld metal to base metal, developed methods of transverse and longitudinal scanning of the focused radiation. Evaluation of electrochemical heterogeneity of the welded joints showed that the laser and laser-arc welding will be achieved much corrosion resistance than the arc. The lowest values of impact toughness of welded joints occur in the case of laser welding with filler wire, and the greatest - in hybrid laser-arc. Also, in the latter case we have the appropriate hardness joints and HAZ. Product Description popup.authors Бернацький Артемій Володимирович Лукашенко Андрій Германович Сіора Олександр Васильович Хаскін Владислав Юрійович popup.nrat_date 2020-04-02 Close