The Forecast of Long-Term Strength of Welded Joints of Pipes of a Siphon of the Underwater Crossing of the Oil Pipeline ESPO(VSTO)-1 across the Lena River

Ammosov A.P., Yakovlev U.A., Kornilova Z.G

 

In this paper stresses depending on constructive and technical features of welded pipe joints parameters are evaluated. Also corrosion of a pipe base metal and welds metal of a pipe joints of a main gas pipeline is discussed. A calculation of stress concentrators in the field of welded pipe joints is carried out. It provides a predictive assessment of corrosion of the base metal and weld metal. The dependence of an oil pipeline wall thinning at various volumes of transported oil is derived. Terms of wall thinning and low-cycle fatigue development to the limit values of deformations in the concentrators are defined. The data on the durability of UTTP pipes, matching a design lifetime is summarized. Based on these data the qualitative forecast of the onset of the critical situation in the HAZ metal of root welds depending on the impact of non-functional loading is made.

Key words: main gas pipeline, siphon, stress-strained state, pressure, corrosion, oil, heat affected zone (HAZ), low cycle fatigue, stress concentrator.

Science and Education, 2017, No.1, pp.81-87