S.V. Rybalko, General Director, Rybalko@neftegazdiagnostika.ru Yu.A. Kosyrev, Lead Enginer A.V. Kolpashikova, Enginer of the 2-nd category OOO «NPP «Neftegazdiagnostika» Ekaterinburg, Russia V.G. Rybalko, Cand. Sci. (Eng.), Senior Researcher Institute of Physics of Metals Named after М.N. Mikheev of Uralian Department of the Russian Academy of Sciences
Since the end of the 1980th years the supply of the liquefied gas — one of the main sources of budget replenishment of the Russian Federation. In the course of gas production and transportation the millions of people and thousands of the organizations of different functions are involved. Any mismatches in the specified process are negatively reflected in the national economy. Gas transportation system of the Russian Federation consists of the millions of kilometers of the main gas pipelines of big diameter (1200 and 1400 mm), which average service life is 30 — 40 years. For this reason the problem has emerged in the course of gas production and transportation — essential accumulation of corrosion damages. One of the most dangerous types of damages is stress-corrosion cracking due to which the main number of accidents occur with gas ignition.
The article considers the issue related to the optimization of expenses and increase in efficiency of technical activities when conducting overhaul of sections of PAO Gazprom main gas pipelines.
At present, in case of diagnostics and repair of the sections of PAO Gazprom main gas pipelines the top-priority approach, according to which all the pipes having crack-like defects in the near-surface metal layer, shall be dismantled and repaired in the shop conditions.
The specified approach is technically complicated, interconnected with essential costs, therefore, it is not always applicable in the real economic conditions.
The accumulated experience in the course of execution of research and development and diagnostic works allows to offer the methods, which are successfully approved at diagnostics of sections of the main gas pipelines that significantly reduces the costs for repair and diagnostics, and also increases the efficiency of the specified activities.
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