ML20057A801
| ML20057A801 | |
| Person / Time | |
|---|---|
| Issue date: | 03/15/1993 |
| From: | Jocelyn Craig NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | Gillespie F, Parler W Office of Nuclear Reactor Regulation, NRC OFFICE OF THE GENERAL COUNSEL (OGC) |
| Shared Package | |
| ML20057A800 | List: |
| References | |
| NUDOCS 9309150339 | |
| Download: ML20057A801 (10) | |
Text
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/ p.nsuq'o UNITED STATES I
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..g NUCLEAR REGULATORY COMMISSION ENCLOSURE p,
r w AsHINGTON. D. C. 20555 g
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MAR 15 ES3 MEMORANDUM FOR:
William C. Parler General Counsel Frank P. Gillespie, Director Program Management, Policy Development i
and Analysis Staff Office of Huclear Reactor Regulation FROM:
John Craig, Deputy Director Division of Engineering Office of Nuclear Regulatory Research
SUBJECT:
REGULATORY GUIDE RL/IEW REQUEST (ASME SECTION XI CODE CASES)
Your assistance is requested in reviewing the enclosed ASME Code Cases and providing comments and recommendations. These Codes Cases are to be considered for input into Revision 11 of the Regulatory Guides on Code Case Acceptability.
The following is a summary of this request.
1.
Guide
Title:
" Inservice Inspection Code case Acceptability, ASME Section XI, Division 1," Regulatory Guide 1.147.
(1)
New Code Cases:
N-494-1, N-503 and N-504 (2)
RES Task No.:
ME-1.147-II (3)
RES Task Leader:
E. O. Woolridge, MEB (4)
Cognizant Individuals:
K. R. Wichman, NRR B. D. Liaw, NRR M. Hum, NRR W. P. Haass, NRR G. Georgiev, NRR R. Hermann, NRR C. Serpan, RES J. E. Richardson, NRR A. J. Murphy, RES J. Muscara, RES J. Strosnider, NRR G. Millman, RES G. Johnson, NRR M. Mayfield, RES J. Norberg, NRR 2.
Requested Action:
Review, comment and make recommendations.
3.
Requested Completion Date: April 30, 1993 9300990 930915033? 930315 PDR ORG NRRD PDR
i MAR 15 503 W. C. Parler/F. P. Gillespie
-2_
4.
Background:
In accordance with the letter from Mr. Minogue dated August 12, 1975, on the subject of Code Case Acceptability, the above referenced Code Cases that were acted upon at ASME Code Meetings subsequent to Revision 11 of the guide are to be considered for input to the guide. This is the only significant change to the guide; therefore, the review need only consider the NRC acceptability of these Code Cases.
i Enclosed with this memo is a listing showing (1) the Code Cases that were acceptable to NRC and that appeared in Revision 10 of the guide, (2) the Code Cases that will be considered for inclusion in Revision 11 of the guides.
If you have any questions, please contact Ed Woolridge at 492-3832.
\\
<> John Craig, Deputy Direc
~
r Division of Engineering Office of Nuclear Regulatory Research
Enclosure:
As stated
)
s s
d 1
APPENDIX NUMERICAL LISTING OF CODE CASES i
N-98 (1705-1)
N-419 i
N-113-1 N-426 N-118 (1738)
N-427 N-211 N-429-1 N-234 N-432 N-235 N-435-1 l
N-236-1 N-436-1 l
N-278 N-437 N-307-1 N-444 i
N-308 N-448 j
N-311 N-449
}
N-335-1 N-457 N-343 N-460 I
N-355 N-461 N-356 N-463-1 N-389 N-465 N-401-1 N-471 N-402 N-472 3
N-408-2 N-479 9
N-4 09-2 N-481 N-415 N-485 i
N-489 l
N-416 N-490-1 N-494 N-495 N-496 i
N-498 RG 1 147 l
1 l
1.147-8 J
=
_j
r CASE N-503 CASES OF ASME BOIIIR AND PRESSLTI %T.SSEL CODE f
1 Approvet Date: February 5.1992 a
See Numericalindex for expirstion snd any reaffirmation dates.
Case N-503 i
certification of nondestructive examination person-Ilmited Certification of nel who are restricted to performing examinations of Nondestructhe Examination Personnel limited scope (i.e., limited operations or limited tech-i Section XI, Division 1 niques within the method). Topics that are not rel-evant for the limited certification may be deleted
, Inquv.y When certifying nondestructive eramina-from the SNT-TC-1A or Appendix VII traming out-tion personnel m accordance with Section XI. Dm-line and may be accompanied by a corresponding sion 1, what alternative rules to those tabulated be-reduction in training hours, eramination content, and low may be used for limited certification of number of exammation questiors. Only questions re-nondestructive examination personnel who are re-lated to the limited training are required. In addition, stricted to performing examinations of limited scope required experience may be reduced by a corre-(i.e., limited operations or limited techmques withm sponding amount. The spec:fic methods and tech-the method)?
ered by limited certification and the train-ing, eramination, and experience requirements for limited certification shall be defined in the written Reply: It is the opinion of the Committee that the practice and documented in the indhidual's certifi-following alternative rules may be used for limited catior. records, t
l
}
EditforvAddenda f
Reference From Up to andIncluding
,i IWA 2300(aM2) 1977 Ed: tion w!th sumrner 1978 1980 Edition Addenda
]W A-2300 tan 3) 1980 Edition w'th winter 19so 1987 EditJon with the 1987 Addenda Adcenda IWA-2350 1997 Edition w!!h the 1988 1992 Edition Adaer.da 1
877 SUPP.12 - NC i
CASE N-504
/
CASES OF ASME BOILER AND PRESSURE VESSTL CODE Approval Date: Aprff 30,1992 See Numericalindex for expiranon and any reamrmadon dates.
y t
a Case N-504 a in. are unacceptable and shall be prepared for weld Alternative Rules for Repair of Class I,2, and 3 reinforcement in accordance with (1) or (2) below:
Austenitic Stainless Steel Piping (1) Unacceptable indication shall be excavated Section XI, Division 1 to the extent necessary to create a casity that can be repaired using qualified welding procedures.
Inquoy Under the rules of IWB-4120, IWC-4120, (2) One or more layers of weld overlay shall be or IWD-4120, in Editions up to and induding the applied to seal unacceptable indications in the area 1989 Edition, and in IWA-4300 in the 1989 Edition to be repaired without excavation. He thickness of with 1989 or 1990 Addenda, a defect may be reduced dese layers shall not be induded in meeting weld to a flaw of acceptable size by either mechaniczl or reinforcement design thickness requirements.
M) H de preparation of M1) oy (2) abe is re-esta ish cep bib f d fe tn r
quired, de area where the weld remforcement is to i
with IWB-3640 by increasing the pipe wall thickness be deposited, m, duding any local repaus or unnal 2
by deposition of weld reinforcement material on the weld overlay layers, shall be mmmed by the hqmd outside surface of the pipe?
penetrant method, and shall contain no indications greater dan % in. prior to application of the struc-Rep & It is the opinion of the Committee that,in tural layers f the weld overlay.
lieu of the requirements of IWB-4120, IWC-4120, or IWD-4120 in Editions up to and including the 1989 (e) The weld reinforcement shaII consist of a min-Edition, and in IWA-4300 in the 1989 Edition with imum of two weld layers having as-deposited delta 1989 or 1990 Addenda, the acceptability of a defect ferrite content of at Icast 7.5 FN. De first layer of weld metal with delta ferrite content of at Icast 7.5 in austenitic stainless steel piping may be established in accordance with IWB-3640 by deposition of weld FN shall constitute the first layer of the weld rein-reinforcement (weld overlay) on' the outside surface forcement design thickness. Alternatively, first layers of the pipe, provided the following requirements are of at least 5 FN may be acceptable based on evalu-ation.
met:
(a) The repair shall be performed in accordance (f) Design of the weld reinforcement shall provide with a Repair Program satisfying the. requirements for access for the examinations required by (i) and 8
ofIWA-4130 in the Edition and Addenda of Section (j) below, and shall be in accordance with (1), (2), or i
XI applicable to the plant inservice inspection pro-(3) below.
gram, or later Edition and Addenda.
(1) For circumferentially oriented flaus greater (b) Reinforcement weld metal shall be low carbon than 10% of the pipe circumference, axial flaws I
(0.035% max.) austenitic stainless steel applied 360 greater than 1.5 in. in length, or more than 5 axial deg.
fiaws of any length, the weld reinforcement shall pro-around the circumference of the pipe, and shall be vide the necessary wall thickness to satisfy the flaw deposited in accordance with a qualified welding p+
evaluation procedures of IWB-3640 from the 1983 cedure specification identified in the Repair P*
Edition with the Winter 1985 Addenda, or later Edi-i gram.
tions and Addenda.The flaw shall be assumed to be (c) Frior to deposition of the weld reinforcement, 100% through the original pipe wall thickness for the the surface to be repaired shall be examined by the entire circumference of the pipe. The axial length liquid penetrant rnethod. Indications greater than /
and end slope of the reinforcement shall be suffi:ient I
8 to provide for load redistribution from the pipe into the deposited weld metal and back into the pipe with-
'when pp!ying this Case to Ed}tions and Addends later than the gg i
1989 E6 tion, reference to Repatr Pnpam shall be read as Repair P
n.a.
prunary local and bending stresses and secondary E.69 SUPP.1 - NC
,/
CASE (continu;d)
N-504 CASES OF AShE BOILER AND PRESSLmTSSEL CODE w
)
(f) Subsequent nondestructive examinations shall include the weld and volume identi5ed in (i) above.
(k) After co:rpletion of all repair activities, the af-i fected restraints, supports, and snubbers shall be VT-3 visually examined to determine if design tolerances are met.
(l) All other applicable requirements of IWA-4000 and IWB-4000, IWC-4000, or IWT)-4000 shall be met.
(m) Use of this Case shall be documented on an NIS-2 form.
i s
d i
B71 SUPP.1 - pgc
I CASE N-494-1 CASES OF ASME BOILER AND FRESSURE VESSEL CODE Approval Dete: J#y 27,1992 See NumericalIndex for expiration r
and sny resmrmstron dates.
l Case N-494-1 teria are applicable to ferritic piping l'~PS 4 or larger Pipe Specific Euluation Procedures and and portions of adjoining pipe fittings within a dis-Acceptance Criteria for Flaws in Class 1 Ferritie tance of VE from the weld centerline ~, where R is 2
Piping that Exceed the Acceptance Standartis of the outside radius and I is the thickness of the pipe.
IWB-3514.2 (b) The evaluation procedures and acceptance cri-Section XI, Division 1 teria are applicable to seamless or welded wrought carbon steel piping and pipe fittings that have a spec-Inquiry: As an alternative to the rules of Section ified minimum yield strength not greater than 40 ksi, XI, Division 1, Appendix H, may Class 1 ferritic pip-and their associated weld materials.
ing containing a flaw that exceeds the acceptance standards of IWB-3514.2 be evaluated and accepted for continued senice as provided in IWB-3132.4 1.2 Acceptance Criteria when actual pipe material toughness properties are (a) Flaws in ferritic piping characterized to have available or when either the PJP., ratios or the P.
eps at be e.W of de eduadon peM greater values exceed the limits for circumferential flaws than 75 percent of the wall thickness are unaccept-stated in Appendix H7 able. Other flaws exceeding the acceptance standards f IWB-3514.2 may be evaluated by analytical pro-Rgl : It is the opinion of the Committee that, as cedures as described m, Appendtx A of this Case.
f an alternative to the rules of Section XI, Division I, Piping containing these other flaws is acceptable for s
I Appendix H, flaws in Class 1 ferritic piping that ex-co.vmed seMee dudng h duad he peM ceed the acceptance standards of IWB-3514.2 may en de the entena in (1) and (2) bek are sah be evaluated for continued senice in accordance fled' with the following procedure.
(1) For each specific set of loading conditions, one er more assessment points with coordinates (S/,
K') shall be inside the fai'ure assessment curve on 1.0 EVALUATION PROCEDURES the applicable failure assessment diagram. For lower AND ACCEI"TANCE CRITERIA shelf and transition temperatures, only one assess-Ferritic piping containing a flaw exceeding the ac.
rnent point is required to be calculated. For upper ceptance standards of IWB-3514.2 may be evaluated shelf temperatures, a series of assessment points for various amounts of ductile f!aw extension may be re-by analytical procedures to determine acceptability for continued senice to the next inspection or to the c; ired to be calculated to meet this criterion.
(2) The S/ coordinate of the assessment point end of senice lifetime. De pipe containing the flaw that satisfies criterion (1) above shaII satisfy is acceptable for continued senice during the eval-uated time period if the criteria of para.1.2 (a) and S/'SF (b) are satisfied.The evaluation shall be the respon-sibi!ity of the Owner and shall be submitted to the regulatory and enforcement authorities hadng juris-
"here S/"""is the limit load cutoff on the applicable fau.ure assessment diagram.
diction at the plant site.
(b) Formulae for (S/, K/) and S,"** are ghen in Appendix A, along with the failure assessment curves. The values of (S/, K') and S aa" are fune-1.1 Evaluation Procedures tions of actual pipe stresses, required safety margins, Evaluation procedures based on use of a failure pipe material properties, end of evaluation period assessment diacram such as in Appendix A of this flaw length and depth, and flaw orientation. Failure Case shall be used, subject to the following:
assessment curves are dependent on flaw o-ientation, (a) ne evaluation procedures and acceptance cri-and for axial fiaws, fla.v depth.
D suPP. 2 - NC
/
CASE N-494-1 CASES OF ASME BOIIIR AND FPISSIJRE Yr.SSE1. CODE APPENDIX A EVALUATION OF FLAWS IN FERRITIC PIPING ARTICLE A-1000 A-1200 PROCEDURE OVERVIEW INTRODUCTION The following is a summary of the analytical pro-A-1100 SCOPE cedure:
ete e
e aw c guradon b the (a) This Appendix provides a method for deter-
""O* * *
^
' "*I"E mining acceptability for continued senice of ferritic A-2000.
piping containing flaws that exceed the allowable W es the actual Daw into cirmmferential flaw standards of IWB-3514.2. The evaluation meth.
odology is based on a fai!ure assessment diapam ap-
- "fd
^
mi 5
m&bM proach that mcludes consideration of the following failure mechanisms:
the location of the detected flaw for normal, upset, emergency, fauhed and test condinons.
(1) brittle fracture described by linear elastic (d) Perform a flaw growth analysis, as described in E fracture mechanics; A 3003, to establish the end of the evaluation period (2) etastic plastic fracture mechanics, when duc-flaw dimensions, af and (f.
tile flaw extension occurs prior to reaching limit load; (c) Obtain actual pipe material properties, E, e,,
(3) limit load failure of the pipe cross section, e and the 1, resistance curve or1, at the temper-r which is reduced by the Eaw area, for ducti!c mate-atures required for analysis.
rials where the limit load is assured.
(f) Select the appropriate failure assessment dia-(b) 'Ihis Appendix accounts for actual pipe mate.
gam cun>e from the figures in A-4200 according to rial toughness properties through input of either the flaw configuration, circumferential or axial, and for 1, resistance curve that characteriaes ductile flaw ex.
axial flaws, ac ording to the ratio of flaw depth to tension, or the fracture toughness,le Flaws are eval.
wall thickness.
uated by comparing the actual pipe applied stress, (g) Calculate the appropriate vertical cutoff, for the flaw size at the end of the evaluation period, S,", for the selected failure assessment diapam with the allowable stress, using the paphical proce.
curve using the formulae in A-4211 or A-4212.
dure of a failure assenment diagram approach. Alj (h) Using the formulae in A-4300, calculate the combinations of applied stresses P. P,,, and P, are anenment point coordinates (S,', K.') for the piping permitted in the evaluation.
stresses P,,, P. and P, for circumferential flaws, or p (c) This Appendix presides rules for flaw model-(pressure) f r axial flaws, using the specified s.afety factors m Tame ANI.
ing and flaw powth. Flaw growth anahsis is based on fatigue. When stress corrosion crack'ing (SCC) is 6) t the anenment points calculated m. (h) active, the growth shall be added to the growth from above on the appropriate failure assen=ent diapam fatigue. The acceptance criteiia of para.1.2 shall in-and apply the accept'ance criteria cf para.1.2 to de-c!ude safety margins on failure for the three failure termine the acceptability of the pipe fer continued
~
mechanisms described above. The acceptance crite-ria shall be used to determine acceptability of the flawed piping for continued senice until the next in-A 1300 NOMENCLATURE specnon, or unn! the end of senice lifetime, or to determine the time interval until a subse:;uent in-The fo!!owing nemenclature is used in this Appen-spection.
dix.
F31 SUFF. 2 - NC
CASE-N-494-1'
'N CASLS OF ASME BODER AND PRES 5t'RE VESSEL CODE t
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4 RG. A-2200-1 Ft.AW CHARACTERIZATION-CIRCUM.
nG. A-2200-2 FLAW CH ARACTERIZATION-AXIAL FERENTIAL FLAWS RAWS P
A-2300 PROXIMTIY TO CLOSE5T FIAW p = Poisson's ratio e = Uow stress, equal to average of yield stress p g g
g ggg f
and engineering ultimate stress, ksi.
distance between the boundaries of two neighboring e.- hoop stress m the pipe at the Daw, ksi flaws is within the pronmity limits speciEed in IWA-c,= yield strengh, ksi 3309, the neighboring flaws shall be bounded by a E
$= angle used in definm.g f.,,, radians r M &&M @ m b accordance with IWA-3300.
ARTICLE A 2000 FIAW MODEL FOR AKtLYSIS A-2100 SCOPE A-2400 FIAW ORIE5TATION
~ntis Article prmides rules for Caw shape, multiple Flaws that lie in neither an axial' not a flaws, flaw orientation, and flaw location used to de-circumferentiaP plane shall be projected onto these planes in accordance with the rules of IWA-3340.
termine acceptance.
He axial and circumferential flaws obtained by these projections shall be evaluated separately in accord-ance with this Appendix Figures A-2400-1, A-24CG A-2200 FIAW SIIAPE 2, and A 2400-3 illustrate flaw characterization for The Daw shall be completely bounded by a rectan-skewed flaws.
gular or circumferential planar area in accordance wnh the rnethods described in IWA-3300. Figures A.
2200-1 and A-22(42 illustrate Daw characterization
'A plane cociaines the pipe aus for circumferential and axial pipe flaws, respectively.
'A plane perpenecular to the pipe exit 833
$UPP. 2 - 740
CASE (continued)
N-494-1 CASES OT ASME BOHIR AND PF1551'RE VF35EL CODE A-2500 FLAW LOCATION (2) Determine the incremental flaw growth cor-rup n&g t M, th fangue Daw grM rate For analysis, the stresses due to system loading cutve f A-4303 of Appendix A.
'll be computed at the flaw locat;on. Surface or s.
.rface flaw characterizations shall be used, de-(c) After all transients have been considered, the peu mg on the type of flaw. Subsurface flaws within pr cedure of (a) ad @) abe 3, elds y hal Daw
- # and the proximity limit of IWA-3340 to the surface of the
!/
f at the end of the daton peM, component shall be considered surface Daws and consdemg o$ fadpie Saw growd shall be bounded by a rectangular or circumferential planar area with the base on the surface.
A-3220 Flaw Orowth Due to Stress Corrosion Cracking (SCC)
Suberitical flaw growth due to SCC has not been ARTICLE A 3000 observed to be a significant Daw growth mechanism FLAW GROWTH ANALYSIS in ferritic piping. When growth due ao SCCis deter-A-3100 SCOPE mined to be active, characterization shall be the re-This Article provides the methodology for deter-mination of suberitical flaw growth during the eva!-
4 uation interval.
ARTICLE A-4000 FAILURE ASSESSMENT DLAGRAM A-3200 SUBCRITICAL FL4W GROMTl!
ANALYSIS AME A-4100 SCOPE When a flaw is characterized in terms of an equiv-
.Ilis Article describes the failure assessment dia-alent anal or circumferennal flaw, the manmum gram procedure for the evaluation of flaws in ferritic depth,o and the maximum length, at the end of f
f the evaluation period sha!! be determmed. Suberiti-piping. The procedure requires:
@I * *
- E * " * *;
cal flaw growth shall be considered. When stress cor-rosion cracking (SCC) is determined to be an active fa ure anenment p e
atu;
- * ##E "" # * * * * * "'
flaw growth mechanism for the pipe being evaluated, SCC shall also be considered. Residual stresses sha!I i
be included for both gtomh mechanisms.
A-4200 FAILURE ASSESSMENT DIAGRAM CURVE A-3210 Subcritical Flaw Growth Due t Failure assessment diagram curves for ferritic pip-l Fatigue ing are used for the following two flaw conBgura-i (a) Fatigue flaw growth shall be computed by tions:
T (a) part-through-wall circumferential flaws under do!.fN - c.(E)-
any combination of primary membrane, primary bending, and expansion stresses (see Fig. A-4211);
4 where K, is the applied stress intensity factor. and n (b) part-through-wall axial flaws under internal and C, are constants dependent on the material and pressure (see Fig. A-4212).
e environmental conditions.
Figure A-4200-1 shall be used for circumferential g
(b) A cumulative fatigue flaw growth calculation flaws of depths up to 75 percent of the pipe wall shall be performed using operating conditions and thickness and lengths up to one-half the inside cir-transients that apply during the evaluation period.
cumference of the pipe.
Each transient shall be considered in approximate Figure A-4200-2 sha!! be used for axial flaws of i
chronological order as follows.
depths up to 75 percent of the pipe wall thickness (1) Determine AK,, the maximum range of K, and lengths up to _, where, is given by the fluctuation associated with the transient.
limit load stability condition for through-wall flaws:
F37 suPP. 2 - NC