A subsurface flaw located near a component surface is transformed to a surface flaw in accordance with a flaw-to-surface proximity rule. The recharacterization process from subsurface to surface flaw is adopted in all fitness-for-service (FFS) codes. However, the criteria of the recharacterizations are different among the FFS codes. In addition, the proximity factors in the rules are generally defined by constant values, irrespective of flaw aspect ratios. This paper describes the stress intensity factor interaction between the subsurface flaw and component free surface and proposes a proximity factor from the point of view of fatigue crack growth rates.

Issue Section:
Expert View
Keywords:
Fatigue, PVP materials, Fracture prediction
Topics:
Fatigue cracks, Stress, Fitness-for-service, Fracture (Materials)

References

1.
Hasegawa
,
K.
, and
Kikuchi
,
M.
,
2008
, “
Rules on Transforming Embedded Flaws to Surface Flaws
,”
ASME
Paper No. PVP2008-61007.
2.
Hasegawa
,
K.
, and
Li
,
Y.
,
2010
, “
Assessment of Fatigue Crack Growths for Transformed Surface Flaws Using FFS Codes
,”
ASME
Paper No. PVP2010-25247.
3.
Hasegawa
,
K.
, and
Li
,
Y.
,
2011
, “
Flaw-to-Surface Proximity Rules and Fatigue Crack Growth Behavior for Transformed Surface Flaws, Structural Integrity in Nuclear Engineering
,”
ISSI 2011
,
Hefei, China
, Oct. 27–30.
4.
Hasegawa
,
K.
,
Li
,
Y.
,
Miyazaki
,
K.
, and
Saito
,
K.
,
2012
, “
Comparison on Experiment and Calculation on Fatigue Crack Growth for Transformed Surface Flaw
,”
ASME
Paper No. PVP2012-78688.
5.
EDF Energy Nuclear Generation
,
2012
, “
R6 Revision 4, Assessment of Integrity of Structures Containing Defects
,”
EDF Energy Nuclear Generation Ltd.
,
Gloucester, UK
.
6.
BSI
,
2005
, “
Guide to Method for Assessing the Acceptability of Flaws in Metallic Structure
,”
British Standard Institution
,
London
, Standard No. BS 7910:2005.
7.
Koçak
,
M.
,
Hadley
,
I.
,
Szavai
,
S.
,
Tkach
,
T.
, and
Taylor
,
N.
,
2008
,
FITNET Fitness-For-Service Procedures
, Vol.
II
,
European Thematic Network FITNET, Geesthacht
,
Germany
.
8.
FKM
,
2009
, “
FKM Guideline, Fracture Mechanics Proof of Strength for Engineering Components
,” 2nd ed.,
Forschungskuratorium Maschinenbau e.V., Frankfurt
,
Germany
.
9.
AFCEN
,
2010
, “
Design, Construction and In-Service Inspection Rules for Nuclear Island Components
,” RSE-M, 2010 ed.,
AFCEN, Lyon
,
France
.
10.
Chinese Standard Committee
,
2004
, “
Safety Assessment for In-Service Pressure Vessels Containing Defects
,” Paper No. GB/T 19624-2004 (in Chinese).
11.
HPI, of Japan
,
2008
, “
Assessment Procedure for Crack Like Flaws in Pressure Equipment
,” (in Japanese), High Pressure Institute of Japan, Tokyo, Standard No. HPIS Z 101.
12.
ASME
,
2013
,
Rules for In-Service Inspection of Nuclear Power Plant Components
,
American Society of Mechanical Engineers
,
New York
, B&PV Code Section XI.
13.
JSME
,
2012
, “
Rules on Fitness-For-Service for Nuclear Power Plants
,” (in Japanese),
Japanese Society of Mechanical Engineers
,
Tokyo
, Standard No. JSME S NA1.
14.
SSM
,
2008
, “
A Combined Deterministic and Probabilistic Procedure for Safety Assessment of Components With Cracks—Handbook
,”
Swedish Radiation Safety Authority
,
Stockholm
.
15.
Commission of Energy Atomic
,
2010
, “
Guide for Defect Assessment and Leak Before Break Analysis
,”
French Alternative Energies and Atomic Energy Commission
,
Paris
.
16.
JWES
,
2007
, “
Method of Assessment for Flaws in Fusion Welded Joints With Respect to Brittle Fracture and Fatigue Crack Growth
,” (in Japanese),
The Japan Welding Engineering Society
,
Tokyo
, Standard No. WES 2805.
17.
Association of Mechanical Engineers
,
2008
, “Calculation of Residual Life of Equipment and Piping in Nuclear Power Plants (VERLIFE),” Association of Mechanical Engineers, Prague, Czech Republic, Section IV.
18.
API
,
2007
, “Recommended Practice for Fitness-for-Service,” 2nd ed., American Petroleum Institute, Washington, DC, Standard No. API 579-1/ASME FFS-1.
19.
Hasegawa
,
K.
,
Li
,
Y.
, and
Saito
,
K.
,
2015
, “
Study on Flaw-To-Surface Proximity Rule of Transformed Surface Flaws Based on Fatigue Crack Growth Experiments
,”
ASME J. Pressure Vessel Technol.
,
137
(
4
), p.
041101
.
Google Scholar
Crossref
Search ADS
 
20.
Hasegawa
,
K.
,
Li
,
Y.
,
Serizawa
,
R.
,
Kikuchi
,
M.
, and
Lacroix
,
V.
,
2016
, “
Proximity Factor on Transformation From Subsurface to Surface Flaw
,”
Procedia Mater. Sci.
(in press).
Copyright © 2016 by ASME
You do not currently have access to this content.