ML20155C057
| ML20155C057 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 05/31/1988 |
| From: | Cofie N, Froehlich C, Sheffield J NUTECH ENGINEERS, INC. |
| To: | |
| Shared Package | |
| ML20155C033 | List: |
| References | |
| CWE-15-203, CWE-15-203-R01, CWE-15-203-R1, NUDOCS 8806140067 | |
| Download: ML20155C057 (69) | |
Text
{{#Wiki_filter:- _ - -
~
1
!C UNDONTROLLED COPY FOR INFORMATION ONLY l CWE-15-203 l Revision 1 May 1988 CWE015.0203 EVALUATION AND DISPOSITION OF FLAWS AT QUAD CITIES NUCLEAR POWER PLANT UNIT 1 (1987 OUTAGE) i Prepared for:
Commonwealth Edison Company Prepared by: NUTECH Engineers Reviewed by: Issued by: N. G. Cofie, Ph.D. J. R. Sheffield,' P.E. Project Engineer Project Manager : Approved by: Dates NAY lA l $h l C. H. Froehlich, P.E. Engineering Manager
)
l nutggh 8806140067 880531 {DR ADOCK0500g4
REVISION CONTROL SHEET l TITLE: Evaluation and Disposition 00CUMENT FILE NUMBER: CWE015.0203 of Flaws at Quad Cities Nuclear Power Pl' ant Unit 1 (1987 Outage) N. G. Cofie/Princioal Consultant M NAME / TITLE INITI ALS C. H. Froehlich, P.E./ Staff Engineer O NAME / TITLE INITI A LS NAME/ TITU INITI ALS NAME / TITLE INITI A LS N AME / TITLE INITI ALS AFFECTED DOC PREPARED ACCURACY CRITERI A
,ggA,gg PAGE(S) REV BY / DATE CHECK SY / DATE CHECE SY /DATE i-viii 0 CN9'49[s1 w,e 12/1/S) u+c s29/sy 1.1 - I 1.14 0 2.1 -
2.6 0 3.1 - 3.8 0 4.1 - 4.12 0 5.1 - 5.14 0 6.1 - 6.2 0 if 7.1 - V y 7.3 see u hley 0 C%3 '%& une nh/n PAGE OF 2 ( C E F 3 3.1 1
l
. '. l j
REVISION CONTROL SHEET (CONTINUATION) TITLE: Evaluation and Disposition DOCUMENT FILE NUMBER: CWE015.0203 of Flaws at Quad Cities Nuclear Power Plant Unit 1 (1987 Outage) AFFECT 1D DOC PHEPARED ACCURACY CmlTEmlA I"# " U P AGE (3) REV SY / DATE CHECK BY / DATE CHECK BY / DATE 2.2- Incorporated NRC comments 2.4 Cu3 542/es unc sla/ry s<a sin /ty
)
1 3.4 1 5.2 1 5.3 1 s 5.10-5 12 1 y NAC y5 //Llc8 OW? //2lgg n Ct rl: pg l l l i e PAGE 2 of 2 ii oEP u.u REV 1
l l CERTIFICATION BY REGISTERED PROFESSIONAL ENGINEER I hereby certify that the revisions to this document and the cal-culations contained herein were prepared by me or under my direct supervision, and to the best of my knowledge are correct and complete. I further certify that, to the best of my knowledge, design margins required by the original Code of Construction have not been reduced as a result of the activities addressed herein. I am a duly Registered Professional Engineer under the laws of the State of California and am competent to review this document. Certified by: gtSS109 47 W, g . W 27B62 C. H. Froehlich, P.E.
\"
9 t,n u ts o 4 Registered Professional Engineer State of California
\Jp Civ [, Registration No. C 027862 Da te : NM N > YY CWE-15-203 iii Revision 1 nut
i
,' )
TABLE OF CONTENTS Pace LIST OF TABLES V LIST OF FIGURES vii
1.0 INTRODUCTION
1.1
- 2. 0 REPAIR DESCRIPTION 2.1 3.0 EVALUATION CRITERIA 3.1 3.1 Stress-Improved Weld Evaluation 3.2 3.1 Conventional Weld Overlay Repair 3. 2 Evaluation 3.3 Weld 02B-S7 Overlay Repair Evaluation 3.4 4.0 APPLIED AND RESIDUAL STRESSES 4.1 4.1 Primary Stresses 4.2 Secondary Stresses 4.1 4.1 5.0 EVALUATION METHODS AND RESULTS 5.1 5.1 Stress-Improved Welds
- 5. 2 5.1
- 5. 3 Conventional Weld Overlay Repairs 5. 2 Wald 02B-S7 Overlay Repair 5.3 6.0
SUMMARY
AND CONCLUSIONS 6.1
7.0 REFERENCES
7.1 CWE-15-203 iv Revision 0 QQf l
LIST OF TABLES Number Title Page 1.0-1 Comparison and Description - Flaws 1.4 Overlay-Repaired 1984 Outage / Built-up 1986 Outage - Quad Cities Unit 1 1.0-2 Comparison and Description - Flaws 1.5 Overlay-Repaired 1984 Outage / Built-up 1987 Outage - Quad Cities Unit 1 1.0-3 Ccaparison and Description - Flaws 1.6 Overlay-Repaired and Pipe Clamped 1984 Outage - Quad Cities Unit 1 1.0-4 Comparison and Description - Flaws IHSI- 1.7 Mitigated 1984 Outage / Overlay-Repaired 1987 Outage - Quad Cities Unit 1 1.0-5 Comparison and Description - Unmitigated 1.8 Flaws Overlay-Repaired 1987 Outage
- Quad Cities Unit 1 1.0-6 Comparison and Description - Flaws 1.9 MSIP-Mitigated 1987 Outage - Quad Cities Unit 1 2.0-1 Quad Citien Unit 1 - Built-Up Weld Overlay 2.3 Repair Details - 1986 and 1987 Outages 2.0-2 Quad Cities Unit 1 - New Weld Overlay 2.4 Repair Details - 1987 Outage 2.0-3 Quad Cities Unit 1 - Pipe Clamped Weld 2.5 Overlay Repair Details - 1984 Outage 3.2-1 Expanded Allowable End-of-Evaluation 3.6 Period Flaw Depth-to-Thickness Ratio for Circumferential Flaws - Normal Operating I Conditions 3.2-2 Leak Barrier Repair Criteria for Axial 3.7 Flaws 4.1-1 Ouad Cities Unit 1 - Primary and Thermal 4.4 Expansion Axial Stresses 4.2-1 Ouad Cities Unit 1 - Total As-Built Weld 4.5 overlay Shrinkages keiisfokb nutggj.)
l l
a LIST OF TABLES (Concluded) Number Title Page 4.2-2 Quad Cities Unit 1 . Weld Overlay Repair 4.6 Axial Shrinkage Stresses 5.1-1 Stress-Improved Flawed Welds - Pipe and 5.5 Flaw Geometric Details 5.1-2 Stress-Improved Flaw 9d Welds - Predicted 5.6 End-of-Fuel Cycle Flaw Depths 5.1-3 Stress-Improved Flawed Welds - Predicted 5.7 End-of-Fuel Cycle Flaw Lengths 5.1-4 Strass-Improved Flawed Welds - ASME 5.8 Section XI Table IWB-3641-5 Predicted vs. Allowable Flaw Depth Ratios 5.2-1 Circumferentially Flawed Overlay-Repaired 5.10 Welds - Pipe and Flaw Geometric Details 5.2-2 Circumferentially Flawed Overlay-Repaired 5.11 Welds - Predicted vs. Allowable Flaw Depth Ratios 5.2-3 Axially Flawed Overlay-Repaired Welds 5.12
- Pipe and Flaw Geometric Details 5.2-4 Axially Flawed Overlay-Repaired Welds 5.13 !
- Applied vs. Allowable Stress Ratios '
5.3-1 Weld 02B-G7 - ASME Section III Code 5.14 Results ( I CWE-15-203 l vi l Revision 0 I
I 1 i LIST OF FIGURES Number Title Pace 1.0-1 Quad Cities Unit 1 - Flawed Weld 1.10 Locations - Reactor Recirculation System Loop "A" 1.0-2 Quad Cities Unit 1 - Flawed Weld 1.11 Locations - Reactor Recirculation Systen Loop "B" 1.0-3 Quad Cities Unit 1 - Flawed Weld 1.12 Locations - Residual Heat Removal (RHR) System Loop "B" 1.0-4 Ouad Cities Unit 1 - Flawed Weld 1.13 Locations - Core Spray System Loop "A" 1.0-5 Ouad Cities Unit 1 - Flawed Weld 1.14 Locations - Core Spray System Loop "B" 2.0-1 General Weld Overlay Repair Details 2. 6
- 1987 Outage 3.1-1 HUREG-0313 Stress-Corrosion Crack 3. 5 Growth Rates 3.2-1 Source Equations for Allowable End-of- 3. 8 Evaluation Period Flaw Depth-to-Thickness Ratios for Circumferential Flaws 4.2-1 Qua6 Cities Unit 1 - Thermal Transients 4.7 4.2-2 Quad Cities Unit 1 - Through-Wall Temperature Gradients 4.8 4.2-3 NUREG-0313 Original Butt-Weld 4.9 Through-Wall Residual Stress Distribution 4.2-4 EPRI Post-IHSI Through-Wall Residual 4.10 Stress Distribution 4.2-5 Post-MSIP Through-Wall Residual Stress i 4.11 !
Distribution I 4.2-6 Under-the-Overlay Through-Wall Residual 4.12 Stress Distribution l CWE-15-203 vii Revision 0 . r1 Lit,qtsit]
. i i
- i LIST OF FIGURES '
(Concluded) Number Title Page ! 5.1-1 IGSCC Crack Growth Correlati'on 5.9 1
- 5. 3 Weld 02B-S7 Finite Element Model 5.15 ,
l l 1 I i i l 1 , i I i I d k i ! CWE-15-203 viii i hevision 0 gg ! ll
. . - . _ . _ _ _ _ _ _ . , . _ _ _ _ - _ _ . , . . , . . _ . . _ _ _ _ _ _ _ . _ , . , . . . _ . .....,._~-,_ __,,, ,. _,_.
1.0 INTRODUCTION
This report summarizes analyses performed by NUTECH to evaluate flaw indications in the Reactor Recirculation, Residual Heat Removal (RHR), and Core Spray systems at Commonwealth Edison's Quad cities Nuclear Power Plant Unit 1. Ultrasonic (UT) examinations of welds in these systems since 1984 have identified flaws judged to be intergranular stress corrosion cracking (IGSCC) in the vicinity of a total of thirty-one welds. Seventeen flawed welds in the Reactor Recirculation system were identified prior to and/or after Induction Heating Stress Improvement (IHSI) mitigation of this system during the 1984 outage. Fourteen additional flawed welds were identified during the 1987 outage. Of these fourteen welds, six flawed welds were discovered in the Core Spray and one flawed weld was discovered in the RHR systems not previously mitigated by a stress improvement process. Of the remaining seven welds, five welds in the previously IHSI-mitigated Reactor Recirculation system were discovered to have only axial flaws. The locations of all these welds are shown in Figures 1.0-1 through 1.0-5. Tables 1.0-1 through 1.0-6 present descriptions of the IGSCC flaw indications at Quad Cities Unit 1. Table 1.0-1 describes flaws in three Reactor Recirculation I system welds which were overlay-repaired during the 1984 outage and built-up to "standard" overlays during the 1986 outage. Table 1.0-2 describes flaws in twelve Reactor Recirculation system welds which were ove rlay-repaired during the 1984 outage and built-up to "s tanda rd" overlays during the 1987 outage. Table 1.0-3 describes flaws in one Reactor Recirculation system weld which was "leak barrier" overlay-repaired in 19 84 and CWE-15-203 1.1 Revision 0 g i
has had a pipe clamping device on it since that time. Teble 1.0-4 describes flaws in eight Reactor Recircula-tion system welds IHSI-mitigated during the 1984 outage and overlay-repaired during the 1987 outage. Only one of these welds had reported IGSCC-indications prior to IHSI mitigation. Table 1.0-5 describes flaws in six unmitigated Core Spray system welds that were overlay-repaired during the 1987 outage. Table 1.0-6 describes flaws in one RHR system weld that was mitigated by the Mechanical Stress Improvement Process (MSIP) during the 1987 outage. The fifteen flawed welds in Tables 1.0-1 and 1.0-2 having "standard" weld overlay repairs have been surf ace finished to permit volumetric inspection of the weld overlay repair and part of the original pipe wall. The one "leak barrier" overlay-repair with the pipe clamping device in Table 1.0-3 was ultrasonically , inspected for bonding between the overlay and original I pipe wall surface in 1984. The fourteen overlay-repaired welds in Tables 1.0-4 and 1.0-5 have been surface finished to permit an ultrasonic bonding inspection of the overlay to the original pipe surface. The design of previous weld overlay repairs and the analysis of IHSI-mitigated weld flaws discovered during the 1984 outage at Quad Cities Unit 1 are described in NUTECH Report COM-96-202 (Reference 1). The evaluation of three weld overlay repairs built-up during the 1986 outage and the effectiveness of one previously IHSI-mitigated flawed weld re-examined during the 1986 outage at Quad Cities Unit 1 is described in NUTECH Report CEC-47-100 (Reference 2). The purpose of this report is to demonstrate that the original design margins of safety for the flawed welds at Quad Cities Unit I have not been degraded by the C WE 2 0 3 1.2 Revision 0 Nfg
presence of IGSCC flaw indications or repairs. In addition, it will be demons trated that all the overlay repairs initially installed during the 1984 outage and built-up to "standard" designs during the 198 6 a nd 1987 outages are adequately sized to meet anticipated changes to regula tory requireme nt s. Section 2.0 presents a general description of the overlay repairs and build-ups performed at Quad Cities Unit 1 during the 1987 outage. Sections 3.0 and 4.0 present the evaluation criteria and loads used in the analysis of overlay-repaired and stress-improved weld flaws. Section 5.0 presents the evaluation methods and resuits. Sections 6.0 and 7.0 present a summary of conclusions and the references used in the evaluation. 1 l 1 l CHE-15-203 1.3 t Revision 0 1 t1LJt.
E k w ww
-~
= G E ""
Q r E RE E E dd
. m m 5 d Y
= = = Q- =d f a E
=
~t J J EE" E *
- gE il 5 h sb" W- .
. 4 .
J J a E E E . E
$ h h S a a &
;5 w w ww
'I ==
3 E - E j w r t EE
,E E EE N k -
W 3 *
- g
- C = E E = EI p _ m -
ca z . 5- , g , O o EE b = W ~ gas" 5s 5 s ss 55 4
- e e
e
< -E5{ g gg"Id3
=
RK m 9 H g d a4 7 v. c 5 z I .: a aa o W y : E I E EE O % @ m v E b b *k n
- M gj "
4 4 :9 c, 4 m w
- 0 Q p 7
- E a u -
a uw wwwwwww wwwww c 2 i o > I c
- =
=
ma massmam samas F w w EE MEEEEEE WEEEE h-EE EEEEEEE EEEEE
% " o s J .
a w! wwwurw! wwwWW r b 8 g cm scsscas O o I'm m . sccca n U v. B 3 .
'S EE U Mggg25
[ w - a...cc E ~M ~~ MU
. a a a
*E .S k k k k.
= .
_ .~__-- .. h. N k..k g
~ . ,
- i. ' !
22% n c a r
- 5 d E l ihhlE i
n . E E E g w E w EE . . . E EG1C C 2 g
. . K. 3 2 $ l WR H M
. A. . .=.
l CWE-15-203 1.4 Revision 0 nut .h
a
=
w a w a E
- wE a-
*Ew!
a- a
- E= w Em Em E E s a a a --
G r r r r I e rf ce IErl r care r Er r Er Er er r mz er EeI i -
= E. E E E !! ifv!
c==a .=
! != E =-n! ==
!! =,s=
= =- --
W- 5 -
= -
=
= == - - = -
-85 p_w. a-s a
s
= - as ss s a s ss s sa a s s s haha a kh h ;ha ;h um 3 a
-s!!
g k
,s k
e
; kk se shsh s e e b
ss e s e e b a a J JJ a: J J Js s J s a e a a y an - e aba a as a ha ga h a d
! h k
kh dhdi
- k. k.h 4_ di. -4. " h_
N s W = 0 Q Z $ o O u
= ., .. .. .. .. 1 .. . .. 1 . .
y L. -s E = u
=
u
= =u u
= = = = = e r =u C
u u y g u u J e < e ~e e e
~
a [ [ _ (( _ [ [ _ _l _t _E _I II fe - - . - _ _ - - - n, u c - m a o 2 E il 9 8 9 8 II 9 nr it ir ay o w W = c m & e e s c *< e w I 0 z ' - - -
" < W F A w
% =
4 z v s =a ww E wwE ME aw .E w ww w e w ww F o >i i = ma na - ma- -- ma r" 3 35 5 5 EE m < e c G rr gr I rrE RE er ci r er r r aa
- a < -
rc .c e tre ce er a r er r r aa x x ~ =
' z
- o a
==
- g. = gav ga ge .,
e gw =
= gn x > c 55 c5 5 c55 c5 =5 5 5 c5 5~ 5 c5-e Wi . - - . ~
O E U m y, g _g gg g. . g.. g. g. . . g. . . g. a k we s. 4 a - a
.a.
e,e J
,n a a a us a .
n, ,us E_
. 5 s-- s n, - e n,-- , -
se , 1 s -
- h.
- c. h. h. -
- . e 1
a
-E'!!Ea:e I
e E E- E E I E E E E ; 5 ; a c - e - - e - _ s n E.!:ir im..r r r r r g e r 3 r c 6 g X .- r r Er u e E
=
EE!b_ L L b b b b L
... - - - - - - b- - b - h h .$
. s = = = a = x ; a : a a E Es 4 e
. i e. *
. .A .A .= * . .A e
. ;, .=
l 1 l l i i l CWE-15-203 1. 5 Revision 0 MUIg,Qb
. = I I S T A K L T B E El G W g, A T U O 7 s 8u! , u 9 isE , 1 ruG m , KL I N T [ E ( E e l l a K t T
- N
_ - E E . J I R i P W O n i I E N P l O , O 6 9si ,. I 9 iu T D 1 IN M 1 P N E 1. ME A . I A G ML I R A T C D T I 3 E U
- S R O N T N
0 E I U E D A 4 E L 1 P 8 S D E 9 E e N R 1 I l A - T s e ,, I t b N Y D C f A a O A E K , T S L P D L , R M I E A A R v L U 'N, A G C O E P - . M Kpl . O S 4 T 3 C W N I A 4 L 9N 9t F 1 r , K
. t N
T.- E E - M I L i K O T B m n EW Se1 uM u- ,i S S I D$ A S m E N
. T MUf Pe EE .
5 o K P P I - m I
,l 5 . n i F
t B t . o-e l t KW - A 8 ntMl wIuo"
- e e-m
-@<EnOa 0 .
)Ce-N 1 !, < ;! 4l .
~
1 1 1 l l n u. as n ness.u.s ! .su urnsag!!!!!.s.us!
.r.r.n.
! r. r. r r r. r r .r. r .! r..r. r..r.r.r.c _. _g a g t r. t. !
.. ... . . . c_.
Ei ** ** * ******
- in ists dissidiis gcg zu 15 as a azzazz s cm cczu cacccccus
-l E e _e _, g. =.
ex,e- .. .. ...... Fm-. _a E xx ,c. E m. s m a s = = s.en .. 1 l I .... i,:s..69 . k 8 8.8...... *. h, .s . _ gn ..,, . g g..,., ,, g g. .. n g..:, g n
\
3 5 ! EEE! "
$ w 5 Effer e==rc I l
= g e o D < s. .....
- e = .. . . .. wwwww 4 g = !8 ,E
- E E @s E ccccc '
e e o
*C O ~
p 8 fa
.I I
- -i ;i -i[ - -l y p $ ee - t' V U EV DE y EEEEE
, .r. =
C C ~ U h , C y C m 5 '
< w z -
w .E, I _h~ - h e _
< a - F i
.c p a < - a e : - o ,,,
g o w . --- M
- 7 mi C 5 f~er l
m > = E I EE E
$ < o l
a E
- u - G G G e s sia r
o a w 38 ! e e a 5E
- Ea E
E cas v > 3 - - o y g y y -g m
< o
-g
!Ea z -
f f 4 4 . sc= a g a f - - g w . s--
- 9 9 s y I
= hhh I
l'a!!r i-
- r. rr
- - ,I r e.
. ,I fs!lI cae I
e I e I
=
g r r g g EEib b b b b h h k 2 : 9 : : ; ms a 5
- x. =. x. =. .A e F
. , E CWE-15-203 1. 7 Revision 0 nut.qqh
i j . I
-a w M
WM w* ww *WE* j Q r 5 55 el er """" r e em te er EEEE
= = _= == == ====
wen a - - -- -- -- ---- E5
-t f. n en n-n E-E n n -- ~~
== n_En: --
I I h.
.k h. h. h.
9h... h *. 3 W G a
< = I D
- E )
O t- :
. = 2 . . .
e .
= - ys E m
- E m W W W o
- c E ," I_
g w I o I W , N b a - _t E R a I E
- x
- 9 0; < b " S U C. - w m
g CO W 2 o W % C g O 1
> v. 3 C < W "
U 2 J -
< a F 2 ,
C *
> L _a l}
s8 - o v, e i
% 3 O
< < O a h 5 g g '
- g '
o 58 - E u o = E r g E W g 5 g= , _E _ _ w w _ g, E2 - s g e g 9_ {r _9 m b , E ( a E. *
- i. sr
*EG 3: Ee R E 3 E e e m!'rr r
I r r g w e r g w r2i. . . . . . rGl* 2
- 2
- 2
" n.
E Y k E I E s _ } s _ _s : CUE-15-203 1.8 Revision 0 nutE9.h
a l KK t I r sS a K L E E P P I P P i . . n E t KCE
! I t n t C se n
i W 7 8 n 9 i t 1 1 r s0 t i2 s n i 3 1". 7 m E 1 4 L u
- e i
T A K L E . - G f A n E l _ N T E n 0 e I E r - O U a T t E P I O W 5 T WI P 7 1 Nn f I 8 9 i 1 P = - R 9 T K - 6 C 1 I _
- S N _
0 E D U _ D E n . 1 T S i m - D A E E - e N G I L l A I T _ b T I a N I C - W- - T O M I - S - D I a I P A K( R I U A S O P M t M E s : O S E C W KpI 4 T E A i M E L W ls I F 4 9u t 9 i _ 1 r e -
- K -
t u sE - ( -
-. NB - m u s
S St K s _ t _ I I 5 E - F E 9 C - 4 E P _
- P K I P
- U ST EE .
P ! .
! . '4 i
P 5 . 1 3 1 B 5 t . - KW 0 0 8 1 w.e xo< a nrnswm@$O s C-
,i j '
- f 4 4 i f 4 1 $ 4
4 02M M - 02K S3 5~
^
02u u #
~
02; u # 4
,/ ' ' 02
- 9 I
,, [4 . .
- f * ',-
6 M ~ l
~ ~ ~
)
-t
'3
~
~
X> FXCLM.0242 l t figure 1.0-1 E AD CITIES UNIT 1 FLAWED WELD LOCATIONS REACTOR RECIRCULATION SYSTEM LOOP "A" (Reference 3) CUE-15-203 1.10 Revision 0 g
e a 02053 02F 53 02E S3 020 53 02C 33 02G 54 g ( 02F 54 02E-$4 020$4 02C 54 U C O 028 s10 028 57 [ [gg g.,i j i
' ' R NTINU T ON i
.85 s5 7
%ah- _X l
_f 028s se \ / F X CE 64.0M1 i Figure 1.0-2 OUAD CITIES UNIT 1 FLAWED WELD LOCATIONS REACTOR RECIRCULATION SYSTEM LOOP "B" (Reference 3) CWE-15-203 1,11 Revision 0 nutgg.b
Stt FIGUP! 10 2 FOR CONTiNWAtl0N N w ( m f I I i 1000 $13 x 13g 3 i
, DAYWELL k
l RHR LOOP 8" ebiYoM 1 Figure 1.0-3 OUAD CITIES UNIT l FLAWED WELD LOCATIONS RESIDUAL HEAT REMOVAL (PHR) SYSTEM LOOP "B" (Reference 4) CWE-15 203 1.12 Revision 0 g l
e . 14A $4 - 14 A 92 q' OZZLE 9
'8
- REACTom BUILDING 14 A F11 DMYWELL e
I Figure 1.0-4 QUAD CITIES UNIT 1 FLAWED WELD LOCATIONS, CORE SPRAY SYSTEM LOOP "A" (Reference 5) Es51H;! 8 2 23 nutggh
sis N0ZZLt
,T 54s $s y i.e n ORYWELL A
REACTOR
/ eVILDING W
\
1 Figure 1.0-5 OUAD CITIES UNIT 1 FLAWED WELD LOCATIONS CORE SPRAY SYSTEM LOOP "B" (Reference 5) CWE-15-203 1.14 Revision 0 nut
2.0 REPAIR DESCRIPTION The weld overlay repairs implemented at Quad Cities Unit 1 can be placed into three categories. The first category is made up of previous weld overlays from the 1984 outage that were built-up during the 1986 and 1987 outages to meet "standard" (full-structural) design ' requirements and to enable adequate surface finishing for nondestructive examination (NDE) of the overlays. The second category consists of new weld overlays that were applied during the 1987 outage. The third category is a "leak barrier" overlay repair that was applied during the 1984 outage and has had a pipe clamping device on it since that time. For all these categories, repairs have been made hv increasing the pipe wall thickness through the deposi-tion of weld metal 360 degrees around and to either side of the existing weld. The weld-deposited band provides additional wall thickness to restore the original Code safety margin. In addition, the welding process pro-duces a strong compressive residual stress patt'ern on the inside portion of the pipe wall (as discussed in the Reference 6 paper), which prevents further crack growth. The deposited weld metal is either Type 308L or Type 309L with contro!1ed delta ferrite content so as to be resistant to the propagation of IGSCC. As-built information for all weld overlays is shown in Figure 2.0-1 and Tables 2.0-1 through 2.0-3. l The nondestructive examination (NDE) of each weld I overlay repair applied at Ouad Cities Unit 1 consisted of the following: i CWE-15-203 2.1 Revision 0 m Illit,E i i
- 1. Surface examination of the existing pipe surface at new weld overlay repair locations by the liquid-penetrant testing (PT) technique in accordance with ASME Section XI.
- 2. Delta forrite content measurement of the first layer of new overlays or the first layer to increase the length of an existing overlay.
- 3. Enhanced visual examination of the first weld overlay layer for evidence of IGSCC flaws for new and built-up overlays (discoloration, porosity, etc.).
- 4. Surface examination of the completed weld overlay by the PT technique in accordance with ASME Section XI.
- 5. For the weld overlay repairs listed in Table 2.0-1, l volumetric examination of the completed weld over-lay repair and part of the original pipe wall by the ultrasonic testing (UT) technique developed by EPRI.
- 6. For the weld overlay repairs listed in Tables 2.0-2 and 2.0-3, UT bonding inspection of the overlay to the original pipe surface in accordance with Commonwealth Edison Special Process Procedures utilizing a straight beam technique.
All UT examinations were performed by EPRI-qualified l examiners. l CWE-15-203 2.2 Revision 1 flu
Table 2.0-1 OUAD CITIES UNIT 1 BUILT-UP WELD OVERLAY REPAIR DETAILS 1986 AND 1987 OUTAGES
'A'$!DE 'I' SIDE TOTAL FIR $f DDR LAYER DELD PlPI WDR (1) COMP 0stLui DIMEN. COMPONENT DIMEN. INICK. THICthtSS NO. $12! TYPE 11PE 'A' (2) TYPE 'l' 12) 't' (3) 'ti' I4) 02C-54 12' 1 Pine 2.125' Elton 2.125' O.424' O.099' 020-54 12' 1 P:se 2.125' Elles 2.125' O.374' W/A 02E 54 12' 1 Pier 2.25' Eller 2.25' O.346' N/A 02F-54 12' 1 Pne 2.0* Elber 2.0' 0.214' O.073' 026 53 12' 1 Elbes 2.312' Piet 2.312' O.300' 0.150' 025-54 12' 1 Pise 2.25' Eltco 2.25' O.331' N/A 02H 53 12' 1 Eltes 2.25' Pier 2.25' O.4 34 ' N/A 02H 54 12' l Piet 2.2!' Eltne 2.25' O.330' N/A 02J-F6 12' i Sere:clet 1.50' Pipe 2.0' O.260' N/A 02J53 12' 1 Elles 2.25' Pise 2.25' O.397' N/A 02J 54 12' 1 Pine 2.375' Eltos 2.375' O.390' N/A 02t-53 12' 1 Ell:s 2.25' Pate 2.25' O.315' uln 02r.-54 12' 1 Pice 2.25' Elboe 2.25' O.315' N/A 021-$7 22' 4 Cross n/A Fine 2.50' O.559' O.102' 029-510 22' 1 Pl e 3.375' End Can 2.375' 0.507' k/A NOTES:
- 1. See Fipre 2.0-1 for eeld overlar repair (WOR) detall types.
- 2. 'A' and 'l' dimensions are eithin 0.125' accura:y.
- 3. Total WDR thittness on flaeed stir of seld.
- 4. First layer thickness, ti, if los delta ferrite nas seasured.
CWE-15-203 2.3 Revision 1 nutp_qh
Table 2.0-2 QUAD CITIES UNIT 1 NEW WELD OVERLAY REPAIR DETAI LS 1987 OUTAGE
'l'$10E TOTAL
_ 'A' ....$10E ...... _ .. .. .... yy IELS PJPT WM (1) CD'IPON(41 OlMEn. IDMPONini DIREN. THlCK. NO. 511E 11PE 1TPE 'A' (2) TYPE 'l' 12) 't' 16A-t2 10' 3 Pjoe 2.250' Safe Esd N/A 0.200' 14A Fil 10' 3 Valve N/A Elber 1.250' O.191' 14A 59 10' 2 Pier 1.75' tiboa 1.75' O.236' 14A-51 10' 2 Eltes 1.375' Pier 1.375' 0.197' 148F2 10' 3 Pise 2.00' Safe End N/A 0.194' 1:1 $9 10' 2 Elles 1.50' tiles 1.50' O.154' 022-!! 12' 2 fines 2.25' Part 2.25' O.160' 02053 12' 2 Elles 2.00' Pier 2.00' O.it!' C2E$3 12' 2 (16cs 2.125' Pise 2.125' O.179' 02F 53 12' 2 f!!:s 2.125' Pise 2.125' O.3 09' 025 54 12' 2 Pine 2. H' Elbes 2.00* 0.321' 021 Fi 22' 3 Pipe 4.375' Valve N/A 0.195' 0235-53 21' 2 Pipe 1.50' fee 1.50' O.231' 0235 St 28' 2 P4se 4.75' Elbes 4.75' O.172-NOTIS:
- 1. See Figce 2.01 for seld everlar repair (WORI detail types.
- 2. 'A' an! 'l' disensical are sithin 0.125' atturate.
CWE-15-203 2.4 Revision 1 nutgg),)
z, - Table 2.0-3 OUAD CITIES UNIT 1 PIPE CLAMPED WELD OVERLAY REPAIR DETAILS 1984 OUTAGE
'A' $1M 'l' SIM TOTAL
.................... ................. . WOR uEd P!PE WOR (1J COMPOWENT DIMER. COMP 0NENT ClMEN. INICK.
BO. $!!E TYPE frPE 'A'(2) ifPE 'l'(2) 't' 0?M $3 12' 1 Elboa 1.625' Pipe 2.25' O.137' NOTES:
- 1. See Figure 2.0 1 for self everley re p ir (NOR) detail types.
- 2. 'A' ano 'l' dimensions are ulthin 0.125' accuracy.
I I 1 CWE-15-203 2.5 Revision 0 nute_qh i-,-. , - , - , , -- --- + -.
, -,----+,y,- - - - -_ - .- y -.-. % ww y--.- , ,,- e- --.m-,,*--
o A l 8 450 MIN. # I
,_ __- __ x
~
._ - ' ~ -
1986 or 1987
.; '] _~ ' ' ' " ' '
-'.7 99,4 V/////////////////)%///////////////O l
-t q WELD Type 1 A B 450 ylq, p -
TYP.
'f+ s_ U:bh65;. $f correnzeisk#DJsrssMa '
-t
( WELD Type 2 A 450 MIN. p TY9 l
. o A A _
twn/s/MManxawMrfr##//41
\ -t I
( WELD
'P/pe 3 i a
\ =
450 MIN v 1987 T 1934 Nh%%%%%%%%N "
-t (WELD Type 4 Figure 2.0-1 GENERAL WELD OVERLAY REPAIR DETAILS 1987 OU' AGE (U.S. Patent No. 4,624,402)
CWE-15-203 2.6 Revision 0 4 NOL
l 1 3.0 EVALUATION CRITERIA 3.1 Stress-Improved Weld Evaluation For the Quad Cities Unit 1 1987 outage, NUTECH has performed flawed pipe eva1uations for Welds 10BD-S13, 02B-F1, 02BS-SS, and 02BS-59 to justify continued operation. Weld 10BD-S13 (see Table 1.0-6) was MSIP-mitigated during the 1987 outage. Welds 0?B-F1, 02BS-SS, and 02BS-S9 (see Table 1.0-4) were stress-improved during the 1987 outage through the use of residual stress improvement "leak barrier" overlay repairs (see Table 2.0-2). The following criteria were used in the evaluation:
- 1. The beginning-of-fuel cycle (evaluation period) bounding flaw size used in the crack growth analysis was the 'as-measured flaw depth by 360 degree circumferential length (conservative).
- 2. The prediction of end-of-fuel cycle (evaluation period) flaw depth was based upon a conservative IGSCC crack growth correlation from NUREG-0313 (Reference 7) as shown in Figure 3.1-1 for a combination of dead weight, internal pressure, differential thermal expansion, and weld overlay shrinkage stresses (caused by weld overlay repair of other welds in the piping system).
- 3. The esiculation of IGSCC flaw growth was based upon conservative original butt-weld, post-IHSI, post-MSIP, and under-the-overlay axial through-wall residual stress distributions.
ElSisf;20g 3.1 nutp_qh
- 4. The prediction of end-of-fuel cycle ~(evaluation period) flaw length was based upon the crack length extension guidelines of NUREG-0313.
- 5. The predicted end-of-fuel cycle (evaluation period) flaw geometry was compared to Table IWB-3641-5 (Reference 8) allowable flaw size values for a combination of dead weight, internal pressure, seismic, differential thermal expansion, and weld overlay shrinkage stresses.
For Welds 02B-F1, 02BS-SS, and 02BS-S9, the thicknesses of the residual stress improvement "leak barrier" overlay repairs were included in the overall pipe wall thickness used in the flawed pipe evaluations. Because these three welds also contain axial flaw indications, the overlay repairs applied to these welds were evaluated in accordance with the axial flaw criteria described in Section 3.2. 3.2 Cpnventional Weld overlay Repair Evaluation Tne following criteria were used by NUTECH to design / evaluate all of the weld overlay repairs shown in Tables 2.0-1 through 2.0-3 (except circumferential flaws in Welds 02B-F1, 02BS-SS, and 02BS-S9) that have been implemented or built-up at Quad Cities Unit 1:
- 1. For welds with circumferential flaws, the circumferertial flaw depth was assumed to equal l 100% of the original pipe wall thickness by a !
conservative 360 degree length.
- 2. For welds with axial flaws, the axial flaw depth was assumed to be a minimum of 100% of the original l l
CWE-15-203 3. 2 Revision 0
pipe wall thickness with a depth equal to the greater of 1.5 times the pipe wall thickness or its measured length. If an axial flaw was drawn up into the overlay due to a steam blow-out, the actual flaw depth was used.
- 3. Credit was taken for the first layer if the delte ferrite content was at least 7.5 FN. If the ferrite content was below this value, any circum-ferential or axial flaws were assumed to extent through the first layer.
- 4. Under-the-overlay repair fatigue crack growth for circumferential and axial flaws was calculated for a 30 year design life based upon a conservative fatigue crack growth correlation derived from data presented in EPRI Document NP-2423-LD (Reference 9).
- 5. For circumferential flaws, the weld overlay repair strength for a combination of dead weight, internal pressure, and seismic stresses was compared to the net section plastic collapse criteria of ASME Section XI, Table IWB-3641-1. Because this table has an arbitrary cut-off point at a stress ratio of
- 0. 6, NUTECH has developed an expanded version (Table 3.2-11 based upon the Table IWB-3641-1 l source equations shown in Figure 3.2-1.
- 6. For axial flaws, the weld overlay repair was l compared to "leak barrier" weld overlay repair ;
criteria presented in Table 3.2-2 from NUTECH Document COM-76-001 (Reference 10). I 1 i l CWE-15-203 3. 3 Reviulon 0 nutg_qh
i 3.3 Weld 028-S7 overlay Repai r L'valuat ion All of the weld overlay repairs shown in Table 2.0-1 have a center of original butt-weld-to-overlay shoulder length approximately equal to the square root of the original pipe wall thickness times mean radius except for Weld 02B-S7 (this simple rule-of-thumb for accept-able weld overlay repair length has been demonstrated both analytically and experimentally by NUTECH and others). Because of a branch line that would not permit the automated welding machine application of a full length over15, at Weld 02B-S7, an overlay length to the pipe side of this weld of only 2.5" was achieved. End effects created by this shortened overlay affect an assumed through-wall-by-360* flaw on the pipe side of this weld to a greater degree than an assumed flaw on the tee side. Therefore,~in addition to the weld overlay repair thickness evaluation criteria discussed in Section 3.2, the stress intensity results of an axisymmetric linear elastic finite element analysis for an assumed through-wall-by-360* flaw on the pipe side of Weld 02B-S7 were compared to ASME Section III (Reference 11), Subsection NB allowable stress intensity criteria. Because this weld had only a single axial flaw indica-tion on its pipe side during the 1984 outage and a single post-overlay axial flaw indication on its tee side during the 1987 outage, only a "leak barrier" I overlay repair is required for this weldment. Therefore, the "standard" overlay repair thickness 1 applied to this weld is very conservative. CWE-15-203 3.4 Revision 1 g
4 10 _ l l l l l 7l _
- NRC CURVE S -
lin /yr g /_" / 10-d -- -
, e -
..gy
,- f j ,/
- 4 E 10 E
,/
/
g
/y ..: ., . io. .i o wri .
y - A ..P" 'd.! II'.ldli;w".i owen . - m (tH e I Uml M g _ Q ..# pas .ti 'i8" ii W f#t4 e- .m - 3 Q ..! p.s S t mit t i.18 E e 10 d O ' o"g','g**' ' 'g g' ' =' ' "> "
- M 604 88 p Siu.i sqfIIf Q e:
g by unlelag; e - 0.04 in /yr i 5-) ousa (sailim riis ...r y a e .n i n..r.rit.
,i .i
*(
d I pp.93r*f/14 I
.) (t.M.te(14 tit'F/1 um l .ma) -
j g: e . sets. e flat *f tte .) (161
- 4 De.I) 10 l c . 4 t;l A:' ! ;, L m ,,. i 11 u i o . (6.st*firti ,. .o .) (tm.
. . . . =nm ,re,t, i. i 3.m ,1 i ; t m. m i e . . n.,;': ,. !..p;; a u 'i = . i m ,,i . .
i p,,.,.,;.u. ,.... .. i x i . io .im ,rs. I .u.n... . u.* s a . .. .... ! 8 il l l I I l 1 1 ! O 10 20 30 40 50 60 70 STRESS INTENSITY,X (ksid.) Figure 3.1-1 NUREG-0313 J STRESS-CORROSION CRACK GROWTH RATES (Reference 7) i CUE-15-203 3. 5 l Revision 0 g{ '
\
wn oz 17 m- Table 3.2-1 s.- e n O e 3w o8 EXPANDED ALLOWABLE END-OF-EVALUATION PERIOD FLAW DEPTilIII-TO-TilICKNESS RATIO FOR CIRCtlMFERENTIAL FLAWS NORMAL OPERATING CONDITIONS P, , Pb Ratio of Flaw Length, A go to Pipe Circumference [ Note (3)] S, 0.5 l Note (2)] 0.0 0.1 0.2 0.3 0.4 or More 1.5 (4) (4) (4) (4) (4) (4) 1.4 0.75 0.40 0.21 0.15 (4 ) (4 ) P' 1.3 0.75 0.75 0.39 0.27 0.22 0.19 as 1.2 0.75 0.75 0.56 0.40 0.32 0.27 1.1 0.75 0.75 0.73 0.51 0.42 0.34 I.0 0.75 0.75 0.75 0.63 0.51 0.41 0.9 0.75 0.75 0.75 0.73 0.59 0.47 0.8 0.75 0.75 0.75 0.75 0.68 0.53 0.7 0.75 0.75 0.75 0.75 0.75 0.58 0.6 0.75 0.75 0.75 0.75 0.75 0.63 0.5 (5) 0.75 0.75 0.75 0.75 0.75 0.68 0.4 (5) 0.75 0.75 0.75 0.75 0.75 0.73 0.36 (5) 0.75 0.75 0.75 0.75 0.75 0.75 NOTES: (1) Flaw depth = a n for a surface flaw 2a for a subsurface flaw t= nominal thlEkness ' Linear interpolation is permissable. (2) P, = primary membrane stress Pb " Primary bending stress l} S ,= allowable design stress ir. tensity (in accordance with Section II!) (3) Carcumference baned on nominal pipe diameter. (4) IWB- 3514.3 shall be used.
# (5) Derived using source equations.
Table 3.2-2 LEAK BARRIER REPAIR CRITERIA FOR AXIAL FLAWS , (Reference 10) l NONDIMENSIONA FLAW LENGTH STRESS RATIO 4/ i om 0.25 0.50 1m 2.00 ..... s , s 0.40 * * *
- 1 l 0.50 * * *
- 1 Om * * * * ;
0.70 * * *
- a
- IWS 3440 0M e * * * =
0.00 * *
- a 0.96 * *
=
1.00 , 1 l
- LEAK SARRIER ONLY REQUIRED #
STRESS RATIO = PD / 2 T Sm P = MAXIMUM PRES $URE FOR NORMAL OPERATING CONDITIONS D = NOMINAL OUT310E DIAMETER OF THE PIPE T = NOMINAL THlCKNESS y = ENDOF. EVALUATION PERIOD FLAW LENGTH R = NOMINAL RAOlut OF THE PtPE CWE-15-203 3. 7 Revision 0 g
e For a *8 ( 1800 1e 8 = (radians) 2 I 2.173 (SR) - 0.5-h(2 sin 8-{sinel=0 rer a
+ B 2 180 6
*(
8= h-{)tradians) 2-{ 2.113 (sm) -0.5-}(2-{} sin s = 0 wnere, o = half-crack length (radians)
= neutral axis location angle (radians) a = flaw depth (inches) t = pipe thickness (inches) !
S R = s t re s s ra t io = Pm + Pb i Pm a primary membrane lIress Pb = primary bending stress I Se = allowable stress intensity l (per ASME Section III Appendices) , I l I 1
. \
l l l u . - a I mA - westral Ants
- m.., a.eiu.
Figure 3.2-1 SOURCE EOUATIONS FOR ALLOWABLE END-OF-EVALUATION PERIOD FLAW DEPTH-TO-THICKNESS RATIOS FOR CIRCUMFERENTIAL FLAWS CWE-15-203 3. 8 Fevision 0 MUk,%,
4.0 APPLIED AND RESIDUAL STRESSES Various stress combinations are used in evaluating IGSCC flaws and repairs as explained in Section 3.0. The purpose of this section is to present the stresses acting on the weld locations discussed in this report. 4.1 Primary Stresses Primary stresses include the effects of dead weight, internal pressure, and seismic loads. The design pressure of 1,250 psi was obtained from the original piping design specification (Reference 12). The dead weight and seismic stresses applied to each weld were obtained from References 13 and 14, respectively. The primary stresses associated with these various loads are shown in Table 4.1-1. 4.2 Secondary Stresses Secondary stresses include piping system differential thermal expansion stresses and through-pipe wall thermal gradient stresses caused by piping system thermal transients; weld overlay shrinkage-induced stresses; and original butt-weld, post-IHSI, post-MSIP, and under-the-overlay through-wall residual stresses.
- 1. Thermal Stresses and Transients The piping system differential thermal expansion stresses for each weld were obtained from Reference 13 ar:d are shown in Table 4.1-1.
l Reference 1 defines the design transients for the recirculation systems for Quad Cities Unit 1. p,7Ejp-20] 7 4.1 nutggjj ;
o e o These transients were conservatively grouped into three composite transients. The first composite transient is a startup/ shutdown transient with a heatup or cooldown rate of 100 degree F per hour. The second composite transient consists of a 50 degree F step temperature change with no change in 4 system internal pressure. The third composite transient is an emergency event with a 416 degree F step temperature change and a system internal pressure change of 75 psi. Figure 4.2-1 presents the number of cycles conservatively postulated during a 30-year balance-of-plant life design. These transients cause the through-wall temperature gradients detailed in Figure 4.2-2.
- 2. Weld Overlay Shrinkage-Induced Stresses Each weld overlay causes a small amount of axial shrinkage underneath the overlay. This shrinkage induces bending stresses in the remainder of the piping system. These shrinkage-induced stresses are calculated using NUTECH computer program PISTAR (Reference 15). The actual as-built shrinkages as l shown in Table 4.2-1 are used in the analysis. The i 1
resulting shrinkage stresses are included in the j IGSCC crack growth analysis of stress-improved welds and are shown in Table 4.2-2.
- 3. Residual Stresses Figure 4.2-3 presents the original butt-weld axial )
through-wall residual stress distribution from l NUREG-0313 (Reference 7) used in the IGSCC crack l growth evaluation of Welds 10BD-S13, 02B-F1, l 02BS-SS, and 02BS-S9. Figure 4.2-4 presents the l l CWE-15-203 4.2 Revision 0 g
. e post-IHSI t}.*, ugh-wall residual stress distribution from EPRI Document NP-2662-LD (Reference 16) used for Welds 02B-F1, 02BS-SS, and 02BS-S9. Figure
- 4. 2-5 presents the post-MSIP through-wall axial residual stress distribution from an O'Donnell and Associates document (Reference 17) used for Weld 10BD-S13.
Figure 4.2-6 presents the under-the-overlay through-wall axial residual stress distributions used for Welds 02B-F1, 02BS-SS, and 02BS-S9. These distributions were determined using the WELDS II computer program (Reference 18). 1 CHE-15-203 4.3 l Revision 0 nutech ,
l l l l i l
=-
c- S 8 E E : E E R E g& E I E E .E. E-
~
!{ !.E I I I 3 3 3 3 3 R- H I i { 3 . )
r,n i w !
$ in- ==a = a=eaaa= t a l g
w IEr
,-- 1 F I 1;=- ii!Ei!!!X!Ei!E8 l
< EaE ,
l x E.ElA L L L L
- g . -L - - - - -L L L . hh h k k F z 1
g o
, sa.!:
jg *g
- 38 g g g 3 $$3 $ $ $ ((
- 2 3 8
- E4 4 59 4
~ " m, a
to < 1 -a y y a, m: = = -a -= * *. - = g - s
- a a g a a =-
- - a
- -g ,
e H ~ M EEE - l
- 1 1
~- y ,
n 4 e, . s . a .a . a . a . a . a . a . a . a . a . a . a . a . a . a . F = ! _ j
< a lat i- g Ig j
= w e o g= _
a
-m- e E e m
- - : 3 gg n e
- ~ _a e a s - -
-i 6 1
c INE s
*~ '
z Isl it - le i e l== E5-'i r r _s_i!_!9E!sR s s s ia.-- sE = 8 t8 5
=a 'g
,$ .E.El6 6- -6 .s. s - - A - L :. s. A L . a.
- a. L ii-!s.5 e 8
- c. -
f a, 7 s?8
- 7 a = a g a a a 9 x =
- a 3 l
- - _s _ e. e. .x x. .e .
m . x. .=. =. = m $ p. a
)s:
3 , 4
~ -
i i I I CWE-15-203 4.4 Revision 0 MWfp_Qh
Table 4.2-1 OUAD CITIES UNIT 1 TOTAL AS-BUILT WELD OVERLAY SHRINKAGES ' AllAL AIIAL u(LD lattwA6( M(LD IMR!aA6C NO. (IN.) N0. (IN.) 144-F2 0.102 026 54 0.305 144F11 0.063 02H 53 0.239 14A $6 0.174 02H 54 0.349 14A St 0.140 02J-F6 0.191 148 F2 0.003 021 53 0.367 i 148 58 0.!!! 02J 54 0.313 02C 53 0.203 ON 53 0.400 02C$4 0.316 03 54 0.220 020 53 0.148 0271$3 0.173 020$4 0.111 02fl54 0.265 02t 53 0.195 021-Fi 0.097 02( 54 0.242 021 57 0.110 02F 53 0.231 028 510 t/A 02F-54 0.31 9 0235-55 0.032 I 026 53 0.270 0295 59 I 0.000 i I fotal of u tal shrintages recorded during 1984,1986, and 1987 outages. l I CWE-15-203 4. 5 1 i Revision 0 MUI,
Table 4.2-2 QUAD CITIES UNIT 1 WELD OVERLAY REPAIR AXI AL SHRINKAGE STRESSES N0$4 - NELD IfM$$ NO. (P$1) 130 $13 692 028 F1 860 0288 $$ 76 0295$f 172 s 8 bold overlay shrinlage (80$1 at stress-leproved flased selfs only. l 1 j l t l 4 1 i i J a 1 CUE-15-203 4.6
! Revision 0 nutggh 4
4 J
. , - . . , . , ---,,. .__,-c, - , . . - , . , , - , , , . . , , , - , . . , , ~ , , , , . . - . , _ ,. ,,n.,,_,-nn,,.,,,,,.n,,-,,. , , , . , _ - _ , . - _ , _ . _ , -
c-l l i i
% *s.
NORWAL opt m ATINC~~ ' 7I l
/
E E e 2 Y
- L AMBIENT -
100 200 CYCLES CYCLES 1 CYCLE 30 YEAR B ALANCE OF PLANT DESIGN LIFE w TIME l Figure 4.2-1 i 1 OUAD CITIES UNIT THERMAL TRANSIENTS i CWE-15-203 4.7 Revision 0 nut
- , - - - -,r,---,, - - - - - - . . , , , - - - - ,,----.
m
- - - -. - - . - - - , - - - - - . . , , y, - .
PIPE PIPE PIPE PIPE O D. 10. 00 10. p \
, . A h
.T,
.AT I .
E.... 2(1 H A T, T 1 y b POR 304$$ AT TNO
- I E = 28.3 a 108 poi u
- 911 a 106/op y = 0.3 PIPE PIPE PIPE PIPE 0.0. I O. O 0. _
l . 0. IL. p p 'a7 2 o E a a7 2
,NO 3 ,,,
h h T, / ' 3. 1-
~- -
Thermal Transient Cycles Pipe Start-up/ 50'F Step 416*F Step Diameter Parameter Shutdown Chance Chance 10" & 1;" aT 1 2*F 32'F 265'r aT 2 0*F 8'F 64'F' 20" to 28" aT 1 6'F 36'F 302'r aT 2 0'F 9'F 75'F Figure 4.2-2 OUAD CITIES UNIT 1 THROUGH-WALL TEMPERATURE GRADIENTS i l CWE-15-203 4.8 Revision 0 g
INSIDE WALL OUTSIDE WALL 50 , ; ; , , ;
; ; g o GE 26 40 g -
o GE 26 (4 ozimuths) a ANL 26 (2 ozimuths) 30[e o ANL 26(IN-SERVICE FROM XRB) 3
- ANL 20 20 -
a g - 5 10 - oo s
; o o * @oo 0 0 -s-- -----
oo o r@- - fg 5
" -10 -
8 ;, o o{4 o o
.{ o a
h oo
-20 - . o M -
o a o
-30 -
e e.
~
0 02 O.4 06 0.8 1.0 o/t 1 Figure 4.2-3 NUREG-0313 ORIGINAL BUTT-WELD THROUGH-WALL RESIDUAL STRESS DISTRIBUTION (Reference 7) CUE-15-203 4.9 Revision 0 g{
= e.
. .. . 0 .. ,w
,. .. . ... 0 ,= >= = em OUTLA $LWFACE f
=w { -,
\. us. i
/
re / _._ . m . .. ; 2 l l 1 - - { 80-10-5 _,3 ?f7;1' """ 1
/ - R *13 0W13 0t tml "
/-"' s E
I/ 3-
/ r
( ik 09
' [
[/ U OS-l I E
/ -t j -e l
X I x i
,_ , I \ , , ,
i a mac: 60 40 ato 0 40 40 60 +40 -,0 0 to 40 MESIDual extal $TMSS, Asl M$louaL CIRCUhW(Ruff LAL $f MESS,in Figure 4.2-4 EPRI POST-IHSI THROUGH-WALL RESIDUAL STRESS DISTRIBUTION (Reference 16) CWE-15-203 4.10 Fevision 0 py{
t 4,m 1.0 - 0 0.9 < - 0.8 - - 0.7 - 06- - l ts / 0.4 < - [0.3 - 0.2 - i Of 0.1 --
\
.. #*/ on l
l 1 l
-M 40 -?0 -20 -10 0 to iu 30 40 stress (ks0 Figure 4.2-5 POST-MSIP THROUGH-WALL RES'. 30AL STRESS DISTRIBUTION ,
(Reference 17) I CWE-15-203 4.11 Revision 0 g
I i 1
\
a0 - 34 3e - te = 8e - t0 - g ie - 6 g 0 0
! Se ,
i a 3 e e e F e e ie ' ' '
! ee , , ,
ea ea ee I . ,e - I e ie a 't s N=
.ge
.a .
.=
22" PIPE TO VALVE 28" PIPE 'IO ELBOW is - e-e- s-s- s-e= 1 i. I a
.. , , , , , i . . i
, , . . 8
., e e i. . ,i y .-
e-
.e -
4-4= 28" PIPE TO TEE Figure 4.2-6 UNDER-THE-OVERLAY THROUGH-WALL RESIDUAL STRESS DISTRIBUTION CWE-15-203 4.12 Revision 0 QQI
5.0 EVALUATION t1ETHODS AND RESULTS This section presents the evaluation methods and results used to assess the acceptability of the overlay-repaired and stress-improved weld flaw indications at Quad Cities Unit 1. 5.1 Stress-Improved Welds
- 1. Flawed Pipe Analysis Table 5.1-1 presents the pipe and flaw geometric details needed to calculate applied stresses and predict crack growth in the stress-improved flawed welds at Quad Cities Unit 1. NUTECH's NUTCRAK computer program (Reference 19) was used to predict crack growth. The conservative crack growth corre-lation shown in Figure 5.1-1 f NUREG-0313 (Reference 7) was used where:
da = differential crack size (inches) dt = dif ferential time (hours) K = applied stress in tensity f actor (ksi 9/ in . ) I l Table 5.1-2 presents the predicted end-of-fuel l cycle (evaluation period) flaw depths for the stress-improved flawed welds for the various through-wall residual stress distributions discussed in Section 4.2. Table 5.1-3 presents the predicted end-of-fuel cycle flaw lengths based upon the predicted flaw depth growth and the flaw length extension guidelinea discussed in Section 3.1. 1 CWE-15-203 5.1 Revision 0 1
- 2. Flawed pipe Evaluation As discussed in Section 3.1, the predicted end-of-fuel cycle flaw geometries were compared to the requirements of ASME Section XI (Reference 8),
Table IWB-3641-5. The results of this evaluation are shown in Table 5.1-4. 5.2 Conventional Weld Overlay Repairs
- 1. Circumferential Flaw Weld Overlay Repair Evaluation Table 5.2-1 presents the pipe and flaw geometry details needed to calculate the applied and allowable stress ratios for all the circumfer-entially flawed overlay-repaired welds at Quad Cities Unit 1 except Welds 02B-F1, 02BS-SS, and 02BS-S9 which are addressed in Section 5.1.
Applie ' stresses are found in Table 4.1-1. Table 5.2-2 presents a comparison of predicted flaw depth ratios due to applied loads versus the allowable flaw depth ratios for the circumferential flaws detailed in Table 5.2-1. As discussed in Section 3.2, the allowable flaw depth ratios shown were calculated using the source equations of AS!!E Section XI Table IWB-3641-1 with an arbitrary maximum allowable flaw depth ratio of 0.75. As a result, all of the weld overlay repairs shown in Table 5.2-2 meet NUREG-0313, Revision 2 "standard" overlay requirements except for Weld 02G-S3. Because post-overlay repair surface conditioning grinding provided a final weld overlay repair thickness below NUTECH's requested "standard" overlay repair design thickness, this overlay has a CWE-15-203 5.2 Revision 3 gg c -
predicted flaw depth ratio (0.77) slightly over the Table IWB-3641-1 maximum allowable flaw depth ratio. Using the alternate flaw evaluation requirements of Paragraph IWB-3642, an applied stress ratio of up to 0.31 is permitted for a flaw ratio fo 0.77 for a net section plastic collapse failure mode (applied stress ratio for Weld 02G-S3 is 0.26). From NUTECH Report CEC-73-205 for Quad Cities Unit 2 Weld 02A-S10 (Reference 21) an applied stress ratio of 0.26 vill not cau7e an unstable tearing failure in a 360' flaw with a depth of up to 80% through-wall (maximum predicted flaw depth ratio for Weld 02G-S3 is 0.77). Because the Weld 02G-S3 overlay repair meets Paragraph IWB-3642 requirements, only requires 0.03" of additional thickness to meet Paragraph IWB-3641 requirements, and has no detected flaws in its low delta ferrite first layer to date, this weld should be considered as a "standard" overlay to avoid additional man-REM exposure associated with either building-up the overlay thickness or increased UT examinations resulting from the classification of this weld as NUREG-0313 Category F instead of Category E.
- 2. Axial Flaw Weld Overlay Repair Evaluation Table 5.2-3 presents the pipe and flaw geometric details needed to determine applied and allowable stress ratios for all the overlay-repaired welds at Quad Cities Unit I with axial flaws. Table 5.2-4 presents a comparison of stress ratios for the axial flaws given in Table 5.2-3. The allowable CWE-15-203 5.3 Revision 1 rititstgit]
stress ratios shown were determined using the leakage barrier criteria presented in Table 3.2-2. , 5.3 Weld 028-S7 Weld overlay Repair Figure 5.3-1 presents the axisymmetric linear elastic finite element model used to evaluate the acceptability of the overlay repair length for Weld 028-S7 at Quad Cities Unit 1. This model contains a 100% through original pipe wall plus low delta ferrite first layer crack depth with a 360 degree length. The ANSYS computer program (Reference 20) was used to perform this analysis for the applied loads corresponding to the stresses shown in Table 4.1-1. A comparison of the maximum applied stress intensities acting through the weld overlay repair over the assumed crack with ASME Section III (Reference 11), Subsection NB allowable stress intensities is presented in Table 5.3-1. l CWE-15-203 5.4 i Revision 0 g{ J
1 \. - O Table 5.1-1 STRESS-IMPROVED FLAWED WELDS PIPE AND FLAW GEOMETRIC DETAILS B0MinAL ai(4) SUSTAINED WELD 0.D.(1) tp (2) to (3) ----------- -------- - L (5) STRESS (6) NO. (lu.) (IN.) (IN.) (1 tp) (IN.) (D(6A((S) (PSI) 1000 513 16.0 0.722 N/A 20 0.144 360 13,230 029-Fi 22.0 1.12 0.115 26 0.211 360 8,169 0295-$5 29.0 1.24 0.231 25 0.31 360 1,520 . 0295 $9 */9.0 1.22 0.172 44 0.537 360 7,207 N0ftSt
- 1. 0.D. = outside disetter.
- 2. tp = pipe sell thickness.
- 3. to a ee!! cverlay repair thickness.
- 4. 41 = beginning-of-fuel cycle (laitial) fles depth. l S. L = tract groeth evaluation flas length. I
- 6. Sustained stress a deadwight + internal pressure + thereal espansion +
n!d overlay shrinkage stresses free tables 4.1 1 and 4.2 2.
)
l l l l CWE-15-203 5.5 Revision 0 nut.
-__.m. __ -.
Table 5.1-2 STRESS-IMPROVED FLAWED WELDS PREDICTED END-OF-FUEL CYCLE FLAW DEPTHS af (2) NURtS0313R.S.(3) PC$i S.I. R.S. (4) POSI NOR R.S. (5) NCLD af (1) - - - - - - - - - - - - - - - NO. (IN.) (IN.) (litp+to)) (IN.) (!(tp+ toll (IN.) (1(tp+to)) 0.144 20 N/A N/A 10lH13 0.144 0.535 74 021-Fi 0.211 0.484 37 0.291 22 0.213 22 02tS 55 0.31 0.674 46 0.31 21 0.337 23 0235 S9 0.537 0.709 51 0.537 39 0.537 39 NOTES:
- 1. ai e beginning of-fuel cycle (initial) flau depth.
- 2. af = end-of fuel cycle flas depth.
- 3. p16-0J13 residual stress (A.S.) distribution (see Figure 4.2-3).
- 4. Eithr lHS1 (see figure 4.2-4) or MIP (see Figure 4.2 5) post stress improvecent (S.I.) asial residual stress (R.S.) distribution.
- 3. Under the-overlay residual stress (R.S.) distritmtions (see Figure ,
4.2 6). ! 1 l CUE-15-203 5.6 Revision 0 nutggh
Table 5.1-3 STRESS-IMPROVED FLAWED WELDS PREDICTED END-OF-FUEL CYCLE FLAW LENGTHS IEPff-03131.3. ($1 Polfl.l.R.5-(3) P0$f-vot 8.l. (5) pinpg -- . ... - . . . . . . . . . . . . utti CDPMv1 41 til LA 121 Ll/st FACTOR Lf til Lf 161 Lf 16) NO. SIM fis. ) (ft.l (3) 13.F.) (4) af/s1 (II.) aflat (18.) aflat ils.) 1087-513 LPltMM 0.144 6.21 43.4 1 3.72 23.2 1 6.25 t/A nrA MIit.M R/A R/A E/A R/4 E/4 t/8 I/A B/A N/A E!A Lf (totall 23.2 6.21 t/A 02341 IPltMM t/8 R/A I/4 I/A I/4 t/A R/4 t/A B/4 n/4 BWltetM 0.291 3.0 10.3 af/a! 1,67 8.37 1 3 1.M 7 1.04 Lt (tetall 1.37 3 3.04 0295 53 UPlfM M 0.31 f.0 29 1 2.17 19.6 1 f.0 1.007 f.11 M11l[M t/8 I/A t/A t/4 t/A 314 t/A 8/4 I/A B/A Lf itetall 19.6 9 9.7) 0295 19 LPltM M 0.537 11.0 N.5 1 1.32 14.5 1 !!.0 1 I I .L' telNM 0. 4H 12.25 2$.1 1 1.43 17.1 1 12.25 1 12.25 Lf itetall 32.3 23.25 23.25 NCril:
- 1. si a kiinning-of fal crcle (initiall flee depth, af e ead-of feel cycle flee depth,
- 2. Li = kginatat of feel cycle inoltlall flee legte.
- 3. Lilas e initial flee site aspect ratie.
- 4. Per EUnil-4313 Inef ereece fis
- a. If Lilas ( 20, neM tutor ll F.) e ef/81
- 6. If Lt/a1 )s 29, l.F. a 1.0.
- 3. See f alle 5.12 acitt for deflaltkens.
- 6. Lf a lef/at} I L 8 8.F.
Endi;M '" nutp_gh
Table 5.1-4 STRESS-IMPROVED FLAWED WELDS ASME SECTION XI TABLE IWB-3641-5 PREDICTED VS. ALLOWABLE FLAW DEPTH RATIOS NURE6 0313 RESIDUAL STRESS P051-S.I. REllDUAL STRESS POST 90R RESIDUAL STRESS PREDl:1ED ALL0eAILE PAfflCTED ALLOWAILE PREDICTED ALL0ealLE NO. S.R. (1) FLR(2) af (I) (3) af(1) FLR(2) af (!) (3) af (U FLR(2) af (1) (3) af(1) 10lD $13 0.718 0.46 74 60 0.12 20 60 N/A N/A h/A 028-F1 0.488 0.12 37 60 0.04 22 60 0.04 22 60 0285-S5 0.498 0.22 46 0.10 60 21 60 0.!! 23 60 02h 59 0.433 0.37 51 60 0.26 39 60 0.26 39 60 NOTES:
- 1. S.R. = M I ((deadseight + internal pressure + seiseic stresses) +
(thereal espansion + self overlay strinkage stressas)/2.77)/fe. Used scrst M s 1.08 for SM4 etldoent eith 29' 04tside diameter. Se = 16,950 psi for J^4 stunlen steel pipe and fittings at 550 degree F oy.2461ng tesperature.
- 2. FLR = flas length ratio e predacted end-of fuel cycle flee length, Lf, divided by noeinal pipe circueference.
- 3. Predicted end of fuel Crtle fl6e depth, af, free Table 5.12.
Egili;Ps \ nutggh i
tv - p vs K for intergrenuter Strese corrosion cracking 150 x 104 K2ast i o M5 1P - l 3xIP 1 I i i 1 i I i I I 1 10 15 20 25 30 40 50 60 70 80 90100 K, (kei . 4 l l Figure 5.1-1 i IGSCC CRACK GROWTH CORRELATION (Reference 7) CWE-15-203 5.9 Revision 0 nutgqh
g e ! l Table 5.2-1 CIRCUMFERENTIALLY FLAWED OVERLAY-REPAIRED WELDS PIPE AND FLAW GEOMETRIC DETAILS ROM!RAL i ELS 0.9. (t) ts 12) to13) tf (4) t (5) tr 16) a (7) L til l
- 10. (It.) (14.) (ItJ (15.1 LII.) flu.I (ll.) (Klatill I 144 51 10.?5 0.632 0.234 0.000 0.548 0.234 0.637 340 CK 54 12.75 4.M4 6.424 0.000 1.010 0.424 0.679 360 !
025 54 12.75 0.600 0.374 0.000 0.M4 0.374 0.605 340 02E 14 12.75 0.611 0.344 0.000 0.957 0.346 0.616 360 l 02F 53 12.75 0.593 0.309 0.000 0.902 0.309 0.599 340 02F14 12.75 0.!I6 0.214 0.073 0.H0 0.214 0.664 360 029 13 12.75 0.604 0.300 0.150 0.906 0.300 0.741 340 02644 12.75 0.671 0.331 0.000 1.010 0.390 0.684 340 02N-33 12.75 0.599 0.434 0.000 1.032 0. 434 4.403 340 02M44 12.75 0.687 0.330 0.000 0,330 1.017 0.692 h0 02146 12.75 0.504 0.260 0.000 0.044 0.260 0.509 34 0 02J43 12.75 0.401 0.397 0.000 0.999 0.397 0.6 04 34 0 02J14 12.75 0. Sit 0.390 0.000 0.909 0.390 0.604 34 0 0313 12.75 0.Hu 0.365 0.000 0.953 0.500 0.H3 340 03$4 12.75 0.504 0.315 0.000 0.099 0.315 0.509 34 0 023 57 22.0 1.073 0.5M 0.102 f.632 0. 5 59 1.190 360 021 110 22.0 1.019 0.H7 0.000 1.526 0.507 1.024 34 0 N01ES:
- 1. 0.I. s estilis tiesetw.
- 2. to e etse nell thittans.
- 3. to' s sold etwley repair thitteess.
- 4. tf a lne falta (write first layer thittaeis (if applit:4te).
- 5. t ts + to.
- 6. tr a sistees resatelag ligaaeet free !!1 esasinattee for tire, flas.
- 7. a a evaluatise flas festh a trestr e4 sts + tl + 0.005' heending f atitte track trewth or (t tr) + 0.005' .
- 3. L e evalsation flas lentti.
CWE-15-203 5,10 Revision 1 nutp_Qh
I 1 I Table 5.2-2 CIRCUMFERENTIALLY FLAWED OVERLAY-REPATRED WELDS PREDICTED VS. ALLOWABLE FLAW DEPTH RATIOS ' Ett IH 3641 1 PRElitiD a0. FLt II) 5.t. (2) FM (3) FM (4) 146-$8 1.0 0.27 0.75 0.73 222-54 1. 0 0.26 0.73 0.67 021-14 1.0 0.25 0.71 0.62 021 14 1.0 0.2A 0.75 0.64 02F 13 1.0 0.21 0.3 0. M 02F H 1.0 0.24 0. 5 0.75 029 13 1.0 0.26 0. 5 0.77 029-54 1.0 0.24 0. 71 0.60 0 3 -53 1. 0 0.24 0. 73 0.50 02H-54 1.0 0.24 0.n 0.64 02J F6 1.0 0.31 0.71 0.70 021 13 1.0 0.25 0. 75 0.61 021 14 1.0 0.25 0.75 .0.61 03 83 1.0 0.24 0.73 0.62 03 54 1. 6 1.27 0.n 0. M i 028 17 1.0 0.29 0n 0.72 023110 1.0 0.27 0.75 0.67 Eith J. 7LR
- flas lpqth ratie e 1.0 f or 340 degree assated flee leegtk.
- 2. 3.R. e dead seight
- inteenal presswe + selselt strestes free free idle 4.11 dividH ty alloodle stress latesity, le, definH in Etti ef felt 5.14.
- 3. FM e alleedle flas festl ratte talt) free AM lection !! tieferente 1), idle 121641 1.
- 4. PredictH FM e bevadist evalsatten fles depth, e, free idle 5.21 divifH tr pipe +
everley initteese, t, free idle 3.2 1. . 1 CWE-lS-203 S.11 Revision 1 nut
- - - ~
Table 5.2-3 i AXIALLY FLAWED OVERLAY-REPAIRED WELDS PIPE AND FLAW GEOMETRIC DETAILS ; unla umla NL) 0.l. (In te (2) L (3) tr' 14) WEL) 0.9. til te (2) L (3) tr' fil E. III.) !!I.) Lit.) !!f.) 5. 115.1 (II.) III.) III.) 14H2 10.73 0.3 92 0. M 2.20 026-14 12.75 0.679 1.M 0.32 14Hil 10.75 0.631 0.?! D.11 029-$3 12.75 0.39f 0.90 0.43 146-50 10.73 0.632 1.50 0.24 02*-$4 12.75 0.641 1.13 0.31 146-31 10.73 0.601 0.90 0.19 021-F6 12.73 0.504 1.25 0.26 14H2 10.73 0.570 0.86 0.11 021 13 12.73 0.601 0.90 0.37 141-$9 10.73 0.557 0N 0.15 02J-54 12.73 0.399 1.10 0.D OK $3 12.75 0.601 0.90 0.14 03 $3 12.73 0.300 0. N 0.35 CK 84 12.73 0.506 1.M 0.60 03 $4 12.73 0.564 0.N 0.32 020-$3 12.75 0.596 0. M 0.11 02#-13 12.73 0.517 0.90 0.14 020-54 12.75 0.600 1.12 0.37 028-$4 12.73 0.640 1.00 0.32 021 53 12.75 6.603 1.00 0.13 02 H 1 22.0 1.095 1. 64 0.11 021 14 12.73 0.611 1.13 0.33 02157 22.0 1.073 1.61 0.56 02F 53 12.75 0.5f3 0. 09 0.31 021 510 22.0 1.019 1.33 0.45 02F 54 12.7) 0.690 1.04 0.37 0235 f3 '10. 0 1.244 1.07 0.22 l CM-$3 12.75 0.4 06 1.13 0.30 029119 29.0 1.232 I
- 1. 05 0.17 Etti:
- 1. 0.9.
- htside dianter.
2.ta e pin sell thittaess. 3.L
- flas evalastian lelth a stentr 64: Reassed a:141 flee lealth Or 1.5 0 19.
- 4. tr'
- IHlif 048 I&td1 A1 Ag Illatest thitt Alls Or 30t thittness (tel.
CWE-15-203 5.12 Revision 1 g
Table 5.2-4 AXIALLY FLAWED OVEPLAY-REPAIRED WELDS APPLIED VS. ALLOWABLE STRESS RATIOS AL0eAILE Stan:6ap ArrLitt AttouAILE $7&M81 PRIDICTED . APPL!!D MLC STRill $1ttil ts (3) te (4) Wil STREll lfRill to (3) NO. RATID(1) RA110121 (II.) lit.) W. RAi!O(1) 14710 (2) (14.) 14A-F2 6.67 0.t0 0.125 0.185 026-54 0.692 0.H 0.125 144-Fil 0.63 0.10 0.125 0.175 ON-83 0.?te 0.90 0.125 i 144-16 0.63 0.00 0.125 0.225 CN-54 0.644 0. H 0.125 l l lla-St 0.66 0.*0 0.1M 0.175 02H6 0.005 0.00 0.!!$ ; 1 141-F2 0.70 0.90 0.!!$ v.!!5 02J 53 0.782 0.90 0.125 141-18 0.68 0.90 0.125 0.135 02J 54 0.795 0.00 0.125 . l 02C 53 0.78 0.90 0.125 0.145 0 3 -53 0.000 0.90 0.125 02(44 0.80 0.00 0.125 0.385 02t 84 0.005 0.00 0.125 021 13 0.79 0.to 4.125 0.175 03 13 0.787 0.90 0.125 020-54 0.78 0.00 0.125 0.355 03 84 0.726 0.00 0.125 021 53 0.78 0.00 0.125 0.165 021 F1 0.741 0.90 0.125 l I 021 54 0.77 9. H 0.125 0.335 021 57 0.756 0.90 0.125 02F 51 0.79 0. M 0.!M 0.2% 028810 0.796 0.90 0.125 02f 14 0.H 0.H 0.125 0.355 02M 55 0.830 0.90 0.125 028 13 0.78 0.H 0.125 0.365 02H St 0.138 0.90 0.125 l Mill:
- 1. Appliti stress ratio is calculatti for internal pressure of 1,250 psi usiel teseetrat properttes free falle 5.2 3 ef formula pisentes in Table 3.2 2 toetnotes.
- 2. Alloestle stress ratto per falle 3.2 2.
- 3. Itatett lest barrier overley repair staisse thittness.
- 4. Predicted tr e tr' free Table 5.2 3 - 0.015' boweding fatiguetracttreeth.
CWE-15-203 5.13 Pevision 0 gg
O Table 5.3-1 WELD 02B-S7 ASME SECTION III CODE RESULTS APPLIED ASME STRESS STRESS USA 6E SECTION111 CAff60Rr INTENSITY FACTOR ALLOWAltE PL (1) 12,770 psi N/A 2:,,425pst PL+0(2) 21,820pst N/A M,8M psi PL + 0 + F (3): N/A Cycle 1 (4) 13,700 pst 0 N/A Cycle 2 (5) 35,770 psi 0.0003 N/A Cycle 3 (6) 219,C90 psi 0.0059 CDPl!NED USA 6E FACTOR: 0.0062 1.0 l NOTES: !
- 1. PL e prieary local seebrane stress inteestty.
- 2. 0 a discontinuity bending stress latensity.
- 3. F e peak stress intensity.
- 4. Cycle 1 e noreal startup/shutdoen thereal transient.
- 5. Cycle 2 a 50 degree F step change thereal tr'ansient. l
- 6. Cytte 3 e 461 degree F step change thersJ) traassent. !
l l l l CUE-15-203 5.14 Revision 0 g{ l
t 4 If l 1 l s w 1 . 1 i i I iii i I I E : '
' t
, j
; i , . 7 2 't I .I I M f \
1 1
,= -
li
, 1 I - ' \
A ^ 3 ! !' ! ! E E
! E
+1 - 3 i
I r s a
-1
- 1 1 m 1 1 1 i g i i,i i T; 1
, l 1 1 i si l I A
. 1 *i 1 1; i 1
= .
a a
- s-g t; j E 1 5; I
1 1 1 $ 1 i I l I l Figure 5.3-1 ' WELD 02B-S7 FINITE ELEMENT MODEL CWE-15-203 5.15 Revision 0 nutp_q.h , l
,_ . _ . ~ . - _. .- .- - - . - .. - -- - .
l e n - 6.0
SUMMARY
AND CONCLUSIONS Ultrasonic (UT) examinations performed during the 1984 outage at Commonwealth Edison's Quad Cities Nuclear Power Plant Unit 1 identified flaws judged to be IGSCC in the vicinity of seventeen welds. Fifteen welds were overlay repaired , one weld was shown to be acceptable with only IHSI mitigation, and one weld was both overlay repaired and covered by a pipe clamping device. During the Quad Cities Unit 1 1986 outage, three of the original fifteen overlay-repaired welds were built-up to "standard" design thicknesses and volumetrically inspected by the UT technique developed by EPRI. The previously IHSI-mitigated weld was also inspected and found to be acceptable for continued operation. None of the other overlay-repaired welds were inspected. During UT examinations performed during the Ouad Cities Unit 1 1987 outage, fourteen new welds were identified as possibly containing IGSCC. Seven of these welds were in systems not stress-improved prior to the 1987 outage. Of the remaining seven welds which were IHSI-mitigated during the 1984 outage, five welds contained only axial flaws which have proven difficult to detect in the past. The last two welds contain relatively minor circumferential indications. Evaluations presented in this report of the thirty-one Quad Cities Unit 1 welds believed to contain IGSCC demonstrates that the applied stress levels are acceptable for all design conditions. The analyses , performed in the evaluation demonstrate that the welds l l l CHE-15-203 6.1 Revision 0 I1LJt
having "standard" weld overlay repairs are acceptable for the balance-of-plant life while all the'other flawed welds are acceptable for a minimum of one additional fuel cycle based upon conservative NUREG-0313 (Reference .7) criteria. 3 e I. 4 4 CWE-15-203 6.2 ' Revision 0 gg
, 'e.
7.0 REFERENCES
- 1. NUTECH Docume nt COM-96-2 0 2, "Evaluation and Disposition of IGSCC Flaws at Quad Cities N0 clear Power Station Unit 1", Revision 0.
- 2. NUTECH Document CEC-4 7-10 0, "Evaluation and Disposition of Indications at Quad Cities Nuclear Power Plant Unit 1", Revision O.
- 3. Sargent & Lundy Drawing No. ISI-103, "Inservice Inspection Class 1 - Nuclear Boiler & Reactor Recirculation Piping - Oua.d cities Station Unit 1",
Revision A.
- 4. Sargent & Lundy Drawing No. ISI-105, "Inservice Inspection Class 1 - RHRS Piping - Quad Cities Station Unit 1", Revision A.
- 5. Sargent & Lundy Drawing No. ISI-104, "Inservice Inspection Class 1 - Core Spray Piping - Quad Cities Station Unit 1", Revision D.
- 6. Kulate S.D., Pitcairn, D.R., and Sobon, L.J.,
"Experimental Verification of Analytically-Determined Weld Overlay Residual Stress Distributions", Transactions of the 8th International Conference on Structural Mechanics in Reactor Technology (SMixT), Paper D2/1, 3russels, Belgium, August 19-23, 198L
~7. NRC Document NUREG-0313, "Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping", Draft Revision 2.
CWE-15-203 7.1 Revision 0 g
- 8. ASME Boiler and Pressure Vessel Code (BPVC) Section XI, 1983 Edition with Addenda through Winter 1985.
- 9. EPRI Document NP-2423-LD, "Stress Corrosion Cracking of Type-304 Stainless Steel in High-Purity Water: A Compilat d 0a of Crack Growth Rates", June 1982.
- 10. NUTECH Document COM-76-001, "Weld overlay Design Criteria for Axial Cracks", Revision 0, March 1984. i l
- 11. ASME BPVC Section III, 1983 Edition with Addenda through Winter 1985.
- 12. Sargent & Lundy Document R-2330, "Specification for Piping System - Quad Cities Units 1 and 2", with l all supplements through Supplement 25. i
- 13. EDS Nuclear Report No. 04-0591-0047, "IGSCC Evaluation for the Piping System of Quad Cities Nuclear Station Unit 1", Revision 0, August 1982.
- 14. IMPELL Letter, W.F. Tschudi to A.K. Rao (NUTECH),
l 1
"Data for IGSCC Evaluation, Quad Cities Unit 1",
April 19, 1984,
- 15. NUTECH Computer Program PISTAR, Version 3.3.1 User's Manual, Volume 1, TR-76-002, Revision 10, NUTECH Corporate File No. 0ASJO. SOFT.2.036.00.
- 16. EPRI Document NP-2662-LD, "Computational Residual Stress Analysis of Induction Heating of Welded BWR Pipes", December 1982.
CWE-15-203 7.2 Revision 0 g
3
.s
- 17. Porowski, J.S., et. al., "Mechanical Methods of Improving Resistance to Stress Corrosion Cracking in BWR Piping Systems", Transactions of SMiRT Post Conference Seminar No. 2, Davos, Switzerland, August 24-25, 1987.
- 18. Computer Program WELDS II, Ve rsion 1.0.0, July 1983, NUTECH Corporate File No.
QASJO. SOFT. 2.052.00.
- 19. NUTECH Computer Program NUTCRAK, Revision 2.0.2, December 1983, NUTECH Corporate File QASJO. SOFT. 2.049.00.
- 20. Computer Program ANSYS, Swanson Analysis Systems, Version 4.1B, NUTECH Corporate File QASJO. SOFT. 2.001.01.
- 21. NUTECH Document CEC-73-205, "Fracture Mechanics Evaluation of Weld 02A-S10 - Quad Cities Nuclear Power Plant Unit 2", Revision 1.
l l l 1 CHE-15-203 7.3 Revision 1 r1Litgtgitj ; 1
--_____-____-__-1.}}