Abstract

An accurate stress estimation for creep evaluation is essential for the long-term safe operation of components at elevated temperature. In general, the section-dependent parameter Kt is defined in elastic analysis routine to account for the reduction in extreme fiber bending stress due to the effect of creep action. A constant value is provided for each cross section in ASME III-5 code, but this may induce underestimation or overestimation of the representative stress of the component due to the relevance of parameter Kt to many factors. Therefore, it is essential to re-examine the validity of the parameter Kt in ASME III-5 code for an adequate creep evaluation. In this work, numerical analyses on beam models with a rectangular section are conducted to calculate parameter Kt, and effects of related factors to the parameter Kt are included. The results reveal that the parameter Kt is closely related to the design life, loading level, operation temperature, and loading combinations. It can be higher than that for the pure bending moment (or tensile loading) with the introduction of the tensile loading (or the bending moment). Meanwhile, the parameter Kt may be higher than the value (i.e., 1.25) in ASME III-5 code for a longer design life, a higher loading level, and a higher operation temperature, inducing an overestimation of the representative stress. On the contrary, a smaller value than 1.25 can be found, inducing an underestimation of the representative stress for creep evaluations.

References

References
1.
Gong
,
J. G.
,
Xia
,
Q. W.
, and
Xuan
,
F. Z.
,
2017
, “
Evaluation of Simplified Creep Design Methods Based on the Cases Analysis of Tee Joint at Elevated Temperature
,”
ASME J. Pressure Vessel Technol.
,
139
(
4
), p.
041412
.10.1115/1.4036533
2.
Koo
,
G. H.
, and
Lee
,
J. H.
,
2006
, “
High Temperature Structural Integrity Evaluation Method and Application Studies by ASME-NH for the Next Generation Reactor Design
,”
J. Mech. Sci. Technol.
,
20
(
12
), pp.
2061
2078
.10.1007/BF02916323
3.
U.S. DOE,
2002
, “A Technology Roadmap for Generation IV Nuclear Energy Systems,”
Nuclear Energy Research Advisory Committee and the Generation IV International Forum, U.S. DOE
,
Washington DC
,
epub
.https://www.gen-4.org/gif/jcms/c_40473/a-technology-roadmap-for-generation-iv-nuclear-energy-systems
4.
Gong
,
J.-G.
,
Niu
,
T.-Y.
,
Chen
,
H.
, and
Xuan
,
F.-Z.
,
2018
, “
Shakedown Analysis of Pressure Pipeline With an Oblique Nozzle at Elevated Temperatures Using the Linear Matching Method
,”
Int. J. Pressure Vessels Piping
,
159
, pp.
55
66
.10.1016/j.ijpvp.2017.11.008
5.
Fanous
,
I. F. Z.
, and
Seshadri
,
R.
,
2007
, “
Stress Classification Using the r-Node Method
,”
Trans. ASME
,
129
(
4
), pp.
676
682
.10.1115/1.2767357
6.
Seshadri
,
R.
, and
Marriott
,
D. L.
,
1993
, “
On Relating the Reference Stress, Limit Load and the ASME Stress Classification Concepts
,”
Int. J. Pressure Vessels Piping
,
56
(
3
), pp.
387
408
.10.1016/0308-0161(93)90007-G
7.
Strzelczyk
,
A. T.
, and
Stojakovic
,
M.
,
2013
, “
Simplified Stress Linearization Method, Maintaining Accuracy
,”
ASME J. Pressure Vessel Technol.
,
135
(
5
), p.
051205
.10.1115/1.4024453
8.
Lu
,
M. W.
,
Yong
,
C.
, and
Li
,
J. G.
,
2000
, “
Two-Step Approach of Stress Classification and Primary Structure Method
,”
ASME J. Pressure Vessel Technol.
,
122
(
1
), pp.
2
8
.10.1115/1.556139
9.
Lee
,
H. Y.
,
2016
, “
Comparison of Elevated Temperature Design Codes of ASME Subsection NH and RCC-MRx
,”
Nucl. Eng. Des.
,
308
, pp.
142
153
.10.1016/j.nucengdes.2016.08.024
10.
ASME
,
2015
, “
ASME Boiler and Pressure Vessel Code, Section III, Division 5, High Temperature Reactors
,”
ASME
,
New York
.
11.
RCC-MRx,
2015
, “
Design and Construction Rules for Mechanical Components of Nuclear Installations: High Temperature, Research and Fusion Reactors
,”
Afcen
,
Paris, France
.
12.
EDF Energy Nuclear Generation, Ltd.
,
2014
, “
Assessment Procedure for the High Temperature Response of Structures
,”
EDF Energy Nuclear Generation
,
London
.
13.
Maan
,
H. J.
,
Camas
,
W.
, and
Robert
,
I. J.
,
2009
, “
Design and Analysis of ASME Boiler and Pressure Vessel Components in the Creep Range
,”
ASME
,
New York
.
14.
Oak Ridge National Laboratory,
1986
, “
Guidelines and Procedures for Design of Class 1 Elevated Temperature Nuclear System Components
,”
Oak Ridge National Laboratory
,
Oak Ridge, TN
.
15.
Penny
,
R. K.
, and
Marriott
,
D. L.
,
1995
,
Design for Creep
, 2nd ed.,
Chapman and Hall
,
London
.
16.
Webster
,
G. A.
, and
Ainsworth
,
R. A.
,
1994
,
High Temperature Component Life Assessment
,
Chapman & Hall/Thomson Press (India), Ltd
,
New Delhi, India
.
17.
ASME
2015
, “
ASME Boiler and Pressure Vessel Code, Section III, Appendices, Nonmandatory Appendix A
,”
ASME
,
New York
.
18.
Zudans
,
Z.
,
Reddi
,
M. M.
,
Fishman
,
H. M.
, and
Tsai
,
H. C.
,
1974
, “
Elastic-Plastic Creep Analysis of High Temperature Nuclear Reactor Components
,”
Nucl. Eng. Des.
,
28
(
3
), pp.
414
445
.10.1016/0029-5493(74)90212-X
19.
Carter
,
P.
,
Sham
,
T. L.
, and
Jetter
,
R. I.
,
2012
, “
Elevated Temperature Primary Load Design Method Using Pseudo Elastic-Perfectly Plastic Model
,”
ASME Paper No. PVP2012-78081
.10.1115/PVP2012-78081
20.
Kobelev
,
V.
,
2014
, “
Some Basic Solutions for Nonlinear Creep
,”
Int. J. Solids Struct.
,
51
(
19–20
), pp.
3372
3381
.10.1016/j.ijsolstr.2014.05.029
21.
Nechache
,
A.
, and
Bouzid
,
A. H.
,
2007
, “
Creep Analysis of Bolted Flange Joints
,”
Int. J. Pressure Vessels Piping
,
84
(
3
), pp.
185
194
.10.1016/j.ijpvp.2006.06.004
22.
Dassault Systèmes Simulia Corporation
,
2009
, “ABAQUS User Manual, Version 6.14,”
Dassault Systèmes Simulia Corporation
,
rovidence, RI
.
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