Bellows structure is used to absorb the thermal expansion maintaining the boundary of the inside to outside, and it is applied to constitute the containment vessel (CV) boundary of the nuclear power plant. In this study, in order to develop the evaluation method of the ultimate strength of the bellows structure subject to internal pressure beyond the specified limit, the failure test and finite element analysis (FEA) of the bellows structure were performed. Several types of the bellows structure made of SUS304 were tested using pressurized water. The failure modes were demonstrated through the test of five and six specimens with six and five convolutions, respectively. Water leakage was caused by contact of the expanded convolution and the neighbor structure in the specimens with the shipping rod mounts. On the other hand, local failure as leakage in the deformation concentrated location and ductile failure as burst in the expanded convolution were observed in the specimen without shipping rod mounts. The maximum pressures in the test observed local and ductile failure were over ten times larger than the estimated values of the limited design pressure for in-plane instability by the EJMA standard. To simulate the buckling and deformation behavior during the test, the implicit and explicit FEA were performed. Because the inversion of the convolution accompanied by convolution contact observed in the test was too difficult a problem for implicit analysis, the maximum pressures in the step of solution converged were compared to the maximum pressures in the tests. On the other hand, explicit analysis enabled to simulate the complex deformation during the test, and the results were evaluated considering ductile failure to compare the test results.

References

References
1.
JSME
,
2012
, “
Codes for Nuclear Power Generation Facilities, Rules on Design and Construction for Nuclear Power Plants, Section ΙΙ Fast Reactor Standards
,” Japan Society of Mechanical Engineers, Tokyo, Japan, No. JSME S NC2-2012 (in Japanese).
2.
EJMA
,
2011
, “
Standards of Expansion Joint Manufacturers Association
,” 9th ed., Expansion Joint Manufacturers Association Inc., New York.
3.
Japan Atomic Energy Agency and Itochu Techno-Solutions
,
2013
, “
FINAS User’s Manual Ver. 21
,”
Japan Atomic Energy Agency and Itochu Techno-Solutions
, Tokyo, Japan (in Japanese).
4.
Dassault Systemes Simulia
,
2016
, “
Abaqus Analysis User’s Manual. Version 2016
,”
Dassault Systemes Simulia, Inc.
, Providence, RI.http://50.16.225.63/v2016/
5.
ASME
,
2012
, “
International Code, 2012 ASME Boiler and Pressure Vessel Code, Section VIII, Rules for Construction of Pressure Vessels, Division 2
,” The American Society of Mechanical Engineers, New York.
6.
PNC
,
1986
, “
Simplified Analysis Methods for Bellows Analyses
,” The Power Reactor and Nuclear Fuel Development Corporation, Tokyo, Japan, PNC Report No. PNC-TN9410 86-128 (in Japanese).
7.
Tsukimori
,
K.
,
Ando
,
M.
, and
Yada
,
H.
,
2015
, “
Study on Behaviours of Multi-Ply Bellows Subjected to Pressure and Displacement Loads
,” Structural Mechanics in Reactor Technology Conference (SMiRT-23), Manchester, UK, Aug. 10–14, Paper No.
076
.https://repository.lib.ncsu.edu/bitstream/handle/1840.20/33900/SMiRT-23_Paper_076.pdf?sequence=1&isAllowed=y
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