Informational and analytical pro- vision for technical conditioning of gas pipelines subject to stress-corrosion cracking
By now Gazprom Transgaz Yekaterinburg LLC is perfecting its System for Management of Technical Condition and Integrity (SMTCI) of gas pipelines on the basis of regulatory documents of Gazprom PJSC. However application of SMTCI at gas pipelines subject to stress corrosion cracking causes some problems. First of all, values of integrated indexes of technical condition do not provide true estimation and ranking of technical conditions due to: insufficient reliability of exposition and identification of different-type crack-like damages by means of intratube inspection; insufficient validity of predictive techniques in respect to revealing potentially dangerous sectors of stress corrosion cracking and determination of their margins. Secondly, regulatory documents, which con- cern decision-making on repair works, do not account absence of data about factual level of gas pipeline dam- age with stress corrosion. So, it is suggested to solve mentioned problems by: selection of potentially dangerous sectors having natural and technical preconditions for origin of stress corrosion according to spatial coincidence of four strategic factors of stress corrosion; forecasting a number of stress-corroded tubes within the frameworks of indicated potentially dangerous sectors according to probable extent of stress- corrosion damage; calculating SMTCI indicators and selecting control responses in accordance with the amount of tubes and ranks of potentially dangerous sectors; using a specialized System for estimation of technical condition, planning and control of repairing gas pipelines subject to stress corrosion at implementation and perfection of SMTCI methodology; designing informational pattern for spatial forecasting in order to detect location and extension of damaged sectors; designing informational pattern for computerized estimation of technical condition and making decisions on repairs using results of intratube inspection and instrumental land diagnostics basing on data about location and extension of potentially dangerous sectors; using applied programs designed on the basis of mentioned informational patterns for calculations and analytical procedures within SMTCI; realizing special systematic arrangements providing reliable and safe operation. Specialized System for estimation of technical condition, planning and control of repairing gas pipe- lines subject to stress corrosion, as well as its software is being used in Gazprom Transgaz Yekaterinburg LLC for support of decision-making while forming the pro- grams of diagnostics and repairs.