The Effect of Variable Loading on Integrity of a Welded Joint of High Alloy-steel X20

Z. Burzić, Military Technical Institute, Belgrade, Serbia. Dž. Gačo, F. Islamović, E. Bajramović, Technical faculty, University of Bihac,Bihac, Bosnia and Herzegovina. M. Burzić, University of Belgrade, I.C. Faculty of Mechanical Engineering, Belgrade, Serbia. In present paper, experimental investigations have included the eff ect of exploitation conditions (exploitation time and temperature) on properties of high-cycle fatigue and parameters of fatigue-crack growth of a welded joint of steel X20 CrM oV 12-1 ( X20). The eff ect of exploitation c onditions was analy sed by testing new pipe and the pipe having been exploited for 116 000 hours. The results obtained by testing and their analysis provide a practical contribution to assessment of quality of a welded joint of steel X20, the aim of which is r evitalisation and extension of exploitation life of vital c omponents of thermal po wer plants manufactured from high-alloy steel for operation at elevated temperatures.