High-cycle fatigue properties until 10⁸ cycles of non-load-carrying cruciform welded joints of JIS-SM490B rolled steel for welded structure were investigated by R=0 and σ_max=σ_y tests which examine effects of plate thickness in welded structures. The plate thickness was 9, 20, 40, 80 and 160mm. The fatigue strengths at 10⁸ cycles for thickness of 80 and 160mm were markedly decreased by σ_max=σ_y test in comparison with those at 10⁷ cycles. Therefore, fatigue limits could not be decided by fatigue strength at 10⁷ cycles.

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In order to rationalize the low cycle fatigue evaluation of elbow piping subject to cyclic in-plane bending displacement, previously carried out pipe elbow test data are reanalyzed. As the result, following conclusions were obtained. (1) It was confirmed that the simplified elastic plastic evaluation method PVB-3315. 1 (2) of JSME Codes for Nuclear Power Generation Facilities-Rules on Design and Construction for Nuclear Power Plants which was allowed to apply in JEAC 4601-2008 had an extreme conservativeness to calculate fictitious stress range of elbow piping. (2) The revised universal slope method can be applicable under reasonable conservativeness in order to evaluate low cycle strength of elbow piping subject to cyclic in-plane bending displacement.

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The contact gasket stress in larger nominal diameter bolted flange connection (20B) with a ring joint gasket (RTJ) was analyzed using FEM and the sealing performance of flange connections with RTJ gasket was examined. The nominal size of flange used is 20B (20inch) with 24 bolts and nuts. The ring gasket type and its material are chosen as octagonal type and Cr-Mo steel. In the sealing performance measurements, the bolts were tightened in accordance with JIS B2251 and ASME PCC-1, respectively while the axial bolt forces were monitored using load cells inserted between the nuts and the flange. It was observed that the difference in scatter of bolt preloads and in the leak rate for the 20B bolted flange connection with RTJ gasket was too small between JIS B2251 and ASME PCC-1. It was also found that the leak rate for the connection decreased as the bolt preloads increased. Furthermore, the stress distributions at the contact surfaces between gasket and the flange groove were calculated using FEM. It was found that the maximum contact stress occurred at the inside of the gasket when the bolt preload was small, however, it occurred at the outside contact surface when the bolt preload was bigger. In addition, the highest contact stress moved to outermost of octagonal gasket under internal pressure. The reason why the sealing performance is better for the connection with RTJ gasket is elucidated due to the double sealing mechanism from a change of the higher contact stress the plastic deformation regions at the octagonal gasket. The tightening coefficient was obtained as 1. 90 in both the tightening methods mentioned above.

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Sloshing response analysis in cylindrical storage tanks based on the velocity potential theory was established in the 1970s. It has been introduced into many seismic design codes for the tanks. This theory is rather complicated. Many young engineers who are unfamiliar with the theory are performing the seismic design of cylindrical storage tanks. This theory has to be handed down to them. In this paper, the velocity potential theory of sloshing response in cylindrical storage tanks which predecessors developed in the 1970s is reviewed.

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The author has reported the incidents of storage facilities for energy products in the EST-1 Committees of High Pressure Institute of Japan. The information was obtained from the Internet at the time of the occurrence of incidents. In this paper, 72 incidents of storage facilities for energy products ocuured in 2013 are introduced.

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