PSI - Issue 22

Olha Zvirko et al. / Procedia Structural Integrity 22 (2019) 299–304

304

6

Olha Zvirko et al. / Structural Integrity Procedia 00 (2019) 000 – 000

Fig. 3. Correlation between relative changes in impact toughness ( KСV deg /KСV in ) and polarisation resistance (R p deg /R p in ) for the low-carbon low alloyed ferrite-pearlite 17H1S and X52 pipeline steels in the as-received (R p in ) and operated (R p deg ) states measured in the solution simulated aqueous condensate in gas transit pipelines, and prediction of the relation KСV deg /KСV in . 4. Summary In-service degradation of the pipeline steels caused a deterioration of their mechanical properties and corrosion resistance. Corrosion resistance degradation of the steels correlated with degradation of their brittle fracture resistance. One of the most sensitive parameter to in-bulk material degradation was polarisation resistance. Impact toughness changes of pipeline steels caused by degradation under operation can be evaluated by measurements of changes in polarisation resistance. Having initial properties of the material, its actual properties can be predicted. Acknowledgements The research has been partially supported by the NATO in the Science for Peace and Security Programme under the Project G5055. References Gabetta, G., Nykyforchyn, H., Lunarska, E., Zonta, P. P., Tsyrulnyk, O. T., Nikiforov, K., Hredil, M. I., Petryna, D. Yu., Vuherer, T., 2008. In service degradation of gas trunk pipeline X52 steel. Materials Science 44, No. 1, 88 – 99. Krasowsky, A.Y., Dolgiy, A.A., Torop, V.M., 2001. Charpy testing to estimate pipeline steel degradation after 30 years of operation, in: Proceedings of Charpy Centary Conference, Poitiers, vol. 1, pp. 489 – 495. Maruschak, P.O., Danyliuk, I.M., Bishchak, R.T., Vuherer, T. 2014. Low temperature impact toughness of the main gas pipeline steel after long term degradation. Central European Journal of Engineering 4, No. 4, 408 – 415. Nykyforchyn, H., Zvirko, O., Tsyrulnyk, O., Kret, N., 2017. Analysis and mechanical properties characterization of operated gas main elbow with hydrogen assisted large-scale delamination. Engineering Failure Analysis 82, 364 – 377. Nykyforchyn, H., Tsyrulnyk, O., Zvirko, O., 2018. Electrochemical fracture analysis of in-service natural gas pipeline steels. Procedia Structural Integrity 13, 1215 – 1220. Tsyrul’nyk , O. T., Nykyforchyn, H. M., Zvirko, O. I., Petryna, D. Yu., 2004. Embrittlement of the steel of an oil-trunk pipeline. Materials Science 40, No. 2, 302 – 304. Tsyrul’nyk, O.T., Slobodyan, Z.V., Zvirko, O.I., Hredil, M.I., Nykyforchyn, H.M., Gabetta, D., 2008. Influence of operation of Kh52 steel on corrosion processes in a model solution of gas condensate. Materials Science 44, No. 5, 619 – 629. Voloshyn V.А., Zvirko О.І., Sydor P.Ya., 2015. Influence of the compositions of neutral soil media on the corrosion cracking of pipe steel. Materials Science 50, No. 5, 671 – 675. Zvirko, O.I., Savula, S.F., Tsependa, V.M., Gabetta, G., Nykyforchyn, H.M., 2016. Stress corrosion cracking of gas pipeline steels of different strength. Procedia Structural Integrity 2, 509 – 516. Zvirko, O.I., Mytsyk, A.B., Tsyrulnyk, O.T., Gabetta, G., Nykyforchyn, H.M., 2017. Corrosion degradation of steel of long-term operated gas pipeline elbow with large-scale delamination. Materials Science 52, No. 6, 861 – 865.