ML20204A540
ML20204A540 | |
Person / Time | |
---|---|
Site: | Brunswick ![]() |
Issue date: | 05/02/1986 |
From: | Froehlich C, Kleinsmith M, Yoshida D NUTECH ENGINEERS, INC. |
To: | |
Shared Package | |
ML20204A535 | List: |
References | |
XCP-34-101-R, XCP-34-101-R00, NUDOCS 8605120324 | |
Download: ML20204A540 (52) | |
Text
NUTECH CONTROLLED COPY XCP-34-101 Revision 0 May 1986 CPLO34.0101 DESIGN REPORT FOR RECIRCULATION SYSTEM WELD OVERLAY REPAIRS AT BRUNSWICK STEAM ELECTRIC PLANT UNIT 2 Prepared for:
Carolina Power and Light Company l
Prepared by: 1 NUTECH, Inc.
San Jose, California Prepared by: Reviewed by:
[. n>w M. E. Kleinsmith C. H. Froehlich, P.E.
Consultant I Project Engineer Approved by: Issued by:
~ .
C. H. Froehlich, P.E. D. K. dshida, P.E.
Engineering Manager Project Manager Date: hk f,/Wd f
860512O324 860508 PDR ADOCK 05000324 G PDR l
nutech
- I REVISION CONTROL SHEET DESIGN REPORT FOR RECIRCULATION SYSTEM WELD OVERLAY REPAIRS AT TITLE
- BRUNSWICK STEAM ELECTRIC DOCUMENT FILE NUMBER: CPLO34.0101 PLANT UNIT 2 M. E. Kleinsmith/ Consultant I hg4 N AME / TITLE INITI A LS C. T. Shyy, P.E./ Senior Engineer dTh N AME / TITLE INITI A LS C. H. Froehlich, P.E. /Staf f Enaineer dNb NAME/ TITLE INITI ALS NAME / TITLE INITI A LS NAME / TITLE INITI A LS AFFECTED DOC PREPARED ACCURACY CRITERI A REMARKS PAGE(S) REV BY / DATE CHECK BY / DATE CHECK BY / DATE i-vi 0 NE9/S.2-E CT3/$.414 C#7/ 5-2 8G Initial Issue l l-16 0 E A.0- 0 A.3 B.0- 0 i B.2 C.0- 0 C.1 D.0- 0 D.2 E.0- 0 Fh 0 Y 1 p r.t fw/s2-es ers /s.e.n eu;jg.2.Sc.
I I
I i
1 1 PAGE OF c E P J 3.1.1 ii 1 REV 1
CERTIFICATION BY REGISTERED PROFESSIONAL ENGINEER I hereby certify that this document and the calculations con-tained herein were prepared under my direct supervision, reviewed by me, and to the best of my knowledge are correct and complete.
I further certify that to the best of my knowledge design margins I required by the original Code of Construction have not been reduced as a result of the repairs addressed herein. I am a duly J Registered Professional Engineer under the laws of the State of California and am competent to review this document.
I
~
k Certified by:
/h$ /kjN l$ % *q &g_ }&d i C. H. Froehlich
'5 Registered Professional Engineer CIVitltlO' State of California gg Registration No. C-27862 Date: 5-2-%
~
XCP-34-101 iii Revision 0
^
nutech k
TABLE OF CONTENTS f
Page LIST OF FIGURES / TABLES y
SUMMARY
vi
1.0 INTRODUCTION
1 2.0 WELD OVERLAY REPAIR DESCRIPTION 5
(
3.0 WELD OVERLAY REPAIR DESIGN CRITERIA 7 4.0 WELD OVERLAY REPAIR EVALUATION 10 5.0 WELD OVERLAY REPAIR SHRINKAGE STRESSES 13
6.0 CONCLUSION
S 16
7.0 REFERENCES
17
, APPENDIX A - 1986 REFUELING OUTAGE FLAW DESCRIPTIONS A.0
. APPENDIX B - APPLIED STRESSES AT FLAWED WELD LOCATIONS B.O APPENDIX C - DESIGN VS. AS-BUILT OVERLAY DIMENSIONS - C.0 1983 OVERLAYS BUILT-UP IN 1986 APPENDIX D - DESIGN VS. AS-BUILT OVERLAY DIMENSIONS - D.0 1986 OVERLAYS APPENDIX E - SHRINKAGE ANALYSIS - INPUT AND RESULTS E.0 APPENDIX F - INPUT TO NUTCRAK ANALYSIS F.0 XCP-34-101 iv Revision 0 nutech
LIST OF FIGURES Figure Title Page 1.1 Repair Locations - Brunswick Unit 2 Recirculation System "A" Loop 3 1.2 Repair Locations - Brunswick Unit 2 Recirculation System "B" Loop . 4 i
- 3.1 Repair Criteria for Axial IGSCC (Reference 6) 9 4.1 Flaw Growth in Leak-Barrier Repaired 28 Inch Pipe 12 5.1 PISTAR Mathematical Model - Brunswick 15 Unit 2 Recirculation System LIST OF TABLES I
)
Table Title Page 3.1 Repair Criteria for Axial IGSCC 9 XCP-34-101 v Revision-0 nutech
SUMMARY
Intergranular stress corrosion cracking (IGSCC) was detected during the 1986 refueling outage adjacent to 34 welds in the Brunswick Unit 2 recirculation system. All of these flawed locations were repaired using the weld overlay technique. Five
.I similarly flawed locations repaired in 1983 were built-up during this outage. All these repairs have been shown to adequately restore design safety margins of the ASME Code, even when highly conservative flaw configurations were assumed. Additionally, weld overlay shrinkage stresses at Brunswick Unit 2 have been I addressed and found not to present problems with respect to inducing flaw growth.
'l l
I I
I l
XCP-34-101 vi Revision 0 nutech
I
1.0 INTRODUCTION
.I During the 1986 Brunswick Unit 2 refueling outage, non-destructive examinations of pipe welds were performed.
These examinations revealed indications judged to be intergranular stress corrosion cracking (IGSCC) at 34 I locations in the recirculation system. Weld overlay repairs were applied at all of these locations.
Additionally, five weld overlay repairs that were applied during the Fall 1983 refueling outage were built-up during this outage (see Figures 1.1 and 1.2 for locations of all repairs).
I The design of weld overlay repairs applied in 1986 was based on conservative flaw assumptions, the ASME Section XI Code (Reference 1), and on USNRC Generic Letter 84-11 (Reference 2). The five overlay repairs applied in 1983 were reevaluated based on this same criteria.
The effect of weld overlay shrinkage stresses on unflawed pipe has been analyzed. This was done by 1
inputting field shrinkage measurements into a computer model of the Brunswick Unit 2 recirculation system.
I XCP-34-101 1 Revision 0 nutech
The purpose of this report is to demonstrate that the design margins of safety at Brunswick Unit 2 have not been degraded, either as a result of IGSCC or weld overlay shrinkage stress. Additionally, this report I documents the fact that all weld overlay repairs applied to 22" diameter and smaller pipe satisfy the require-ments of the current ASME Section XI code (Reference 1) as well as the requirements for full structural overlay repairs as set forth in the USNRC Generic Letter 84-11 (Reference 2). Finally, the fact that weld overlay leak barriers applied to 28" diameter pipe astigate the growth of -shallow circumferential flaw , is also documented.
I 1
1 1
1 1
1 1
XCP-34-101 2 Revision 0 -
] nutech
Figure 1.1 ,
1 f REPAIR LOCATIONS - BRUNSWICK UNIT 2 l RECIRCULATION SYSTEM "A" LOOP Q RPV
' 12. A R 3 2 AR.A3 12.AR E4 , s
-+12 - A R . A2
' 8 12 AR E3 g
- 12. AR.E2 t A 041 i
k 2 AR 83 2.AR-82 s 23.A4
[
n %s% C1 y'^
r s 12. A R. -
i 4 -
tp .A.,,
3
. A,2
)
% 4A.1 00 1r 60 LOOP A l
i XCP-34-101 3 Revision 0 nutech ll
Figure 1.2 REPAIR LOCATIONS - BRUNSWICK UNIT 2 RECIRCULATION SYSTEM "B" LOOP 12 BR H4 12-8R H2
- 12 8R G4* 12 8R J;* 12 8R J3 .12 8R-K3*
12-BR G3 9 12SR K2*
12-8R 42 ff22 8M1 28 83
{ K '
12-BR F4 12-BR-F 3 28 84 3
7%#{ .
J f28 8s i a :
. 1 oo g o / s, h s
, %# l' 48 1 l0 48 11 l 28-811 01 LOOP B
- 1983 WELD OVERLAY REPAIRS l
XCP-34-101 4 Revision 0 i nutech
2.0 WELD OVERLAY REPAIR DESCRIPTION Appendix A contains a listing of the welds determined to contain flaws during the 1986 outage, as well as a description of those flaws. The welds listed in Appendix A have been repaired by applying additional
" cast-in-place" pipe wall thickness with weld metal deposited 360' around and to either side of the existing weld. The weld-deposited band provides, as a minimum, II wall thickness necessary to meet the requirements of ASME Section XI (Reference 1) as modified by NRC Generic Letter 84-11 (Reference 2), which requires that the first weld overlay layer not be included in the design l
thickness of full structural overlays (leak barrier l overlay repairs, which were applied to 28" diameter pipe, are not addressed in GL 84-11). The full struc-tural weld overlays also meet the requirements of Table IWB-3641-5, which is presented in the 1985 Addenda to the ASME Section XI code. Design and as-built informa-tion for each overlay is given in Appendices C and D.
Besides the additional pipe wall thickness, the welding process produces a favorable compressive residual stress pattern on the inside portion of the pipe wall which inhibits further IGSCC growth and mitigates the possi-l bility of new flaw initiation. The deposited weld metal XCP-34-101 5 I Revision 0 l nutech
is Type 308L which is resistant to IGSCC propagation because of its duplex (austenite-ferrite) structure.
Nondestructive examinations of each weld overlay '
consisted of:
1:
1.
- 1. Surface examination of the first weld overlay layer l' by the liquid penetrant examination technique in accordance with USNRC Generic Letter 84-11 (Reference 2).
i
- 2. Delta ferrite content measurement of the first layer using a Severn gauge. [;
- 3. .I Surface examination of the completed weld overlay .I by the liquid penetrant examination technique, in accordance with ASME Section XI (Reference 1).
- 4. Ultrasonic examination of the weld overlay and existing circumferential pipe weld in accordance with ASME Section XI (Reference 1).
XCP-34-101 6 Revision 0 nutech
3.0 WELD OVERLAY REPAIR DESIGN CRITERIA The following conservative criteria were used by NUTECH to design and evaluate the weld overlay repairs for all 22" diameter and smaller welds with flaw indications, including welds repaired in 1983 (Reference 3):
- 1. An IGSCC-induced circumferential flaw was assumed to have a 100% through-wall-by-360* length geometry.
l l
- 2. A bounding fatigue-induced flaw growth of 0.010" into the overlay material was used based upon the NUTECH design report for recirculation safe end and f
elbow repairs at Monticello Nuclear Generating
- Plant (Reference 4).
- 3. The weld overlay repairs were evaluated for a combination of dead weight, internal pressure, and scismic stresses and compared to the net section collapse criteria of ASME Section XI (Reference 1)
Paragraph IWB-3640. Stresses were obtained from Reference 5, and are reported in Appendix B.
Weld overlay repairs applied to 28" diameter piping were designed using a leak barrier approach since the axially XCP-34-101 7 Revision 0 nutech
oriented flaws governed the repair desi'n. The leak barrier overlays were designed assuming an axial flaw extended 100% through-wall over its measured length per Table 3.1 (from Reference 6). These weld overlays are applied to stop potential leakage of axially oriented flaws, and are a minimum of 2 layers thick.
XCP-34-101 8 Revision 0 nutech
I Table 3.1 1
REPAIR CRITERIA FOR AXIAL IGSCC (REFERENCE 6)
NON0lMENSIONAL FLAW LENGTH STRESS RAT 10 4//KT 0.00 0.25 0.50 1.00 2.00 . . . .
s 0.40 . . .
s 0.50 . . . . ;
0.60 * . * .
a 0.70 * . . . a
- lWB-3640 0.80 . . . .
2 EM * . .
2 ;
0.95 * . -
i I 1.00 2
)
- LEAK 8ARRIER ONLY REQUIRE 0 sc0 m ALL DEFINITICNS SAME AS IW8 3640 (REFERENCE 1)
STRESS RATIO = PO /2 T Sm P = MAXIMUM PRESSURE FOR NORMAL OPERATING CCNDITIONS O = NOMINAL OUTSICE DIAMETER OF THE PIPE T = NOMINAL THICXNESS 4 = END-OF EVALUATION PERICO FLAW LENGTH R = NOMINAL RADIUS OF THE PIPE i
XCP-34-101 9 Revision 0 nutech
4.0 WELD OVERLAY REPAIR EVALUATION Weld overlay repairs at Brunswick Unit 2 fall into three categories: 1) Those applied during the 1983 refueling outage; 2) those applied to pipe less than 28" NPS during the 1986 refueling outage; and 3) those applied u
to 28" NPS pipe during the 1986 refueling outage. Five overlay repairs were applied during the 1983 refueling outage. They are at the following locations:
2B32-RR-12-BR-G4 2B32-RR-12-BR-K2 3
2B32-RR-12-BR-J2 2B32-RR-12-BR-K3
'2B32-RR-12-BR-J3 Full structural weld overlay repairs at these locations b
were designed based on the conservative design criteria j
.I presented in Section 2.0. This design thickness was compared with the as-built thickness, less a 0.10" allowance for the first layer, in accordance with Generic Letter 84-11. In all five cases the as-built thicknesses were increased-by depositing additional weld metal. Details of design and as-built overlay dimen-sions are found in Appendix C. The as-built dimensions for each of these weld overlays meet or exceed design dimensions.
t XCP-34-101 10 Revision 0 nutech
Flawed pipe with NPS less than 28" repaired during the 1986 refueling outage were designed using the design criteria of Section 3.0. Design and as-built overlay dimensions are presented in Appendix D and as-built 4
m dimensions meet or exceed design di mensions.
I The flawed 28" pipe welds all contained axial flaws and, except weld 2B32-RR-28-A8, small circumferential flaws. Weld overlay repairs were designed in accordance with the leakage barrier criteria of Section 3.0.
Application of these leak barrier overlay repairs was
' I analyzed to assess its impact on circumferential flaw g growth. It was shown that circumferential flaws would not exceed allowable flaw depths for at least 30 years (see Figure 4.1).
.I I
L l
XCP-34-101 11 Revision 0 nutech
Figure 4.1 FLAW GROWTH IN LEAK-BARRIER REPAIRED 28 INCH PIPE I
100 -
1 1 --
J PIU Z*
m@J< 60 -
.I w
$g$
3 ALLOWABLE FLAW OEPTH (50%)
yNd I a 40 -
1 INITIAL FLAW DEPTH (24%)
20 -
i i a i i i 5 to 15 20 25 30 TIME (YEARS) i l
l XCP-34-101 12 Revision 0 nutech L
I 5.0 WELD OVERLAY REPAIR SHRINKAGE STRESSES A certain amount of axial shrinkage is associated with each weld overlay repair. Appendix E contains a listing
~
of the shrinkage at each weld overlay location. These shrinkages induce stresses throughout the recirculation system. NUTECH's computer program PISTAR (Reference 7) was used to determine the magnitude of these stresses.
Figure 5.1 presents the PISTAR mathematical model used.
The calculated stresses are listed in Appendix E at un-
. flawed locations.
Weld overlay shrinkage stresses were evaluated to assure they do not contribute to crack growth in unflawed pipe.
Since all unflawed pipe welds (except for the twelve (12) Inconel safe-end to nozzle welds at the reactor I pressure vessel and the two (2) 4" decon connections on the 28" suction lines) in the Brunswick Unit 2 recircu-lation system have been treated by the Induction Heating l Stress Improvement (IHSI) process, the favorable resi-dual stresses imposed by this process would have to be
'! overcome to induce IGSCC. Further analyses demonstrated that the highest combination of deadweight, internal
~
pressure, thermal, and weld overlay shrinkage stresses present at any weld would not overcome the post-IMSI compressive residual stresses.
XCP-34-101 13 Revision 0 nutech
t I .
e ,
1 These analyses were performed using NUTECH's computer program NUTCRAK (Reference 8). It was demonstrated that i the stress intensity factor at the tip of a 10% through-wall x 360* flaw (a 10% flaw depth was chosen since that is a typical threshold depth for reportability) would be negative given the above combination of stresses and, therefore, no crack growth would take place. Details of the analysis input are contained in Appendix F. l
-l I
f I f i:
i:
e
'b XCP-34-101 14 Revision 0 nutech i
,y-,--,_., .-y,.,,_.,e..~,., ,.m_,wom,,.m._,,,yy,___.,,,,,,,m..m,.,_.,,m._m.,_., ,__,.,,wm__.,,,_. _.y_m,, _ _ . _ _ , . - . . , _ . - _ _ , _ . . . , - -
e Figure 5.1 PISTAR MATHEMATICAL MODEL -
BRUNSWICK UNIT 2 RECIRCULATION SYSTEM t
192 82 180 132 190 N2B 130 4A N1A ggg US _
128 162 N*
190 A 192A 160 186 176 126 N23 188A -
A N2H '
N2E"%' 158 i 184 180A N2F 124 186A 122 1 254 178A 8A 130A 152_ f150T 172A T 184A 160A 170A 120T
\
\
256 I
176A 128A 452 264 j 152A 126A
' ^ ' 4 150TA 944 gggA N G M 124A 166A 6 r 1407
\\ 44A 122A 1207A 154A 164A 112 343 16A g ' 272 134A 142A ,0T s
136TH 138A 140TA 130 274 7
252A 116A 254A 18A j944 108 12 204 256A 258A " 06 1 273 106 264A 266A 268A 270A 2O0 272 280 20A 274A 210 220 222 110A E e 276A 16 22A 2!8 224 ,
30A 108A 1
10 24A 278A 28A 280A 106A 282A ig 73 26A ,
104A 24 70 22 l 1
\
- 4 XCP-34-101 15 Revision 0 nutech
(
6.0 CONCLUSION
S As can be seen from the information presented in Appendices C and D, weld overlay repaired flawed pipe !
welds meet ASME Section XI requirements and Generic i i Letter 84-11 full-structural overlay repair requirements i
-i 4
on 22" diameter and smaller pipe. Additionally, all ;
t weld overlays applied to 28" diameter pipes meet leak barrier overlay repair requirements and the resulting residual stress limits growth of circumferential flaws to acceptable values. No flawed pipe was left t
unrepaired.
Finally, it has been demonstrated that stresses due to f
weld overlay shrinkage are not of great enough magnitude
- ,- to overcome the post-IHSI compressive residual stress present at unflawed locations (Appendices E and F).
Therefore, these residual stresses should remain 4
effective in mitigating the initiation of IGSCC. g, l
r 1
5 3
XCP-34-101 16 Revision 0 nutech
'l ,
~
4
7.0 REFERENCES
r .
- 1. ASME Boiler and Pressure Vessel Code,Section XI, 1983 Edition with Addenda through Winter 1984. j l1.
- 2. USNRC Generic Letter 84-11, " Inspections of BWR Stainless Steel Piping," dated April 19, 1984, File Number CPLO34.001 .
, ~.
,,' L,
- 3. NUTECH Report CPL-13-104, '" Design Report forTWeld 1P Overlay Repairs at B'runswick Steam Electric Plant
,i Unit 2," Revision 1, File Number CPLO34.0012,
- 4. NUTECH Report NSP-81-105,. " Design Report for Re-I circulation Safe End and Elbow Repairs - Monticello Nuclear' Generating Plant," Revision 0, File Number CPLO34.0012. ,
- 5. Carolina Power and Light Docume nt , " Brunswick Nuclear Project DBD for Weld Overlay Repair" (TAR B84-022), dated ~8/19/85, File Number CPLO34.0012.
- 6. NUTECH Report COM-76-001, " Weld Overlay Design Criteria for Axial Cracks," Revision 0, File Number CPLO34.0012.
XCP-34-101 17 Revision 0 nutech I
a
- 7. NUTECH Computer Program PISTAR, Leve l 3.1.1, File Number QASJO. SOFT.036.3.30.2.
I
- 8. NUTECH Computer Program NUTCRAK, Version 2.0.2, File Number QASJO. SOFT.049.2.0.0,'.
I 9. "BSEP Unit 2 IGSCC Indication List," all revisions through 13, File Number CPLO34.0012.
I 10. " Weld Overlay As-Built Dimensions," CPL File Number PM-85-030, Rev. O, File Number CPLO34.0012.
i
- 11. U.S. Nuclear Regulatory Commission Document No.
NUREG-1061, Volume 1, " Investigation and Evaluation of Stress-Corrosion Cracking in Piping of Boiling Water Reactor Plants," April 1984, Second Draf t
~
attached to SECY-84-301, dated July 30, 1984.
I
- 12. EPRI Document No. NP-2662-LD, " Computational Residual Stress Analysis for Induction Heating of Welded BWR Pipes," December 1982.
XCP-34-101 18 Revision 0 nutech
p i
+
4 t-
- 'I i !
. +
4
!I i
I i e 4 i i 4 1 J i
. I i
- j. i ,
- 1 1-i APPENDIX A 1
b d
- j. 1986 REFUELING OUTAGE FLAW DESCRIPTIONS d
i
\'
i t
4.
5.
e 5 I
4 4
i t
i i
3 1.
a i
1 l
1 k
6 2
i 1
A.0 i
5 k
nutech
[
, Pipe Pipe Wall Weld ID Size lhickness Configuration (II Flaw DescriptionI4) 2B32-RR-4A-1 4" 0.36" P-WOL Through-wall defect,
! weld-o-let side 2B32-RR-4A-ll 4" 0.36" P-WOL Through-wall defect, weld-o-let side 2832-RR-4B-1 4" 0.36" P-W L Through-wall defect, weld m-let side 2B32-RR-4B-ll 4" 0.36" P-WOL (2) 2B32-RR-12-AR-A2 12" 0.70" P-E Axial, 0.20" length, pipe side 2B32-RR-12-AR-A3 12" 0.80" E-P 5 axials, 0.25" max. ;
length, elbow side !
2B32-RR-12-AR-B2 12" 0.70" P-E 0.60" x 20% circ.(3) ,
pipe side i 2B32-RR-12-AR-B3 12" 0.68" E-P 1.00" x 20% circ.(3) ,
elbow side 2832-RR-12-AR-Cl 12" 0.68" SWD-P 3.0" x 100% circ.,
3 axials, 0.30" nnx.
- length, all pipe side 2B32-RR-12-AR-C2 12" 0.76" P-E 3 axials, 0.60" max.
le.ngth, elbow side 2B32-RR-12-AR-C3 12" 0.78" E-P 3 axials, 0.40" max.
length, elbow side 2B32-RR-12-AR-C4 12" 0.70" P-PP 7.4" x 38% circ.(3) ,
pipe side 2B32-RR-12-AR-D1 12" 0.62" SWP-P 3.0" x 25% circ.(3) ,
pipe side 2B32-RR-12-AR-D4 12" 0.62" P-PP Axial, 0.20" length, pup piece side; axial, 0.35" length, pipe side 2B32-RR-12-AR-E2 12" 0.80" P-E 7 axials, 0.60" max.
length, elbow side 2832-RR-12-AR-E3 12" 0.76" E-P Axial, 0.35" length, elbow side XCP-34-101 A.1 Revision 0 nutech
Pipe Pipe Wall I Weld ID Size Thickness ConficurationII) Flaw Description (4
=2B32-RR-12-AR-E4 12" 0.63" P-PP Axial, 0.20" length, pipe side 2832-RR-12-BR-F2 12" 0.70" P-E 2 axials, 0.75" max.
i length, pipe side 2832-RR-12-BR-F3 12" 0.55" E-P Axial, 0.55" length, elbow side 2B32-RR-12-BR-F4 12" 0.70" P-PP Axial, 0.40" length, j pipe side 2B32-RR-12-BR-G1 12" 0.63" SWP-P Pinhole leak, pipe side 2B32-RR-12-BR-G2 12" 0.63" P-E Axial, 0.40" length, pipe side 2B32-RR-12-BR-G3 12" 0.77" E-P 3 axials, 0.75" max.
length, elbow side 2B32-RR-12-BR-H2 12" 0.68" P-E Axial, 0.50" length, pipe side 2B32-RR-12-BR-H4 12" 0.72" P-PP 2 axials, 0.60" max. I 1 length, pipe side l
- 2B32-RR-22-AM5 22" 1.10" CR-P 0.50" x 20% circ.(3) , (;
0.50" x 18% cire. I:
0.40" x 18% circ.I3) all pipe side
. 2B32-RR-22-BM1 22" 1.15" P-EC 2.50" x 58% circ.(3) 0.25" x 23% cire (3), ,
t 4.0" x 25% circ.(3) ,
all end cap side
, 2332-RR-28-A4 28" 1.19" E-P 1.10" x 24% circ.,
eltcw side, 1.25" x 20% circ.(3) ,
pipe side, 0.6" x 4% circ.,
elbow side, 1.3" x 12% circ.,
al b.45" max. !
length, elbow side, j axial 0.5" length, !
pipe side '
XCP-34-101 A.2
- Revision 0 nutech
Pipe Pipe Wall Weld ID Size Thickness Configuration III Flaw [hscriotionI4) 2B32-RR-28-A8 28" 1.30" E-V 2 axials, 0.75" max.
length, elbow side
..,. 2B32-RR-28-A13 28" 1.50" P-V 1. 2" x 10% circ. ( 3 ) ,
.1 pipe side 2832-RR-28-B3 28" 1.17" P-E 4 cires.(3) , 21% x 8.0" (nux, depth x j]i total length); axial, 0.40" length; all
- , elbow side l
i' 2B32-RR-28-B4 28" 1.20" E-P 6 cires.(3) , 24% x 6.9" (max. depth x total length), axial, 0.30" length, all elbow side 2B32-RR-28-B5 28" 1.19" P-P 4 cires.(3), 27% x '
6.25" (max. depth x total length), up-stream side l-
' l:
2B32-RR-28-B11 28" 1.27" E-Pp 1.2" x 18% circ.(3) elbow side
{
3
- ( .
Notes:
- 1) P = Pipe, WOL = Weldolet, E = Elbow, PP = Pup Piece, SWP = Sweepolet, EC = End Cap, V = Valve, Cr = Cross,.
Pp = Punp.
- 2) tb flaw detected but weld overlay repaired as a pre-cautionary measure.
- 3) Circumferentially oriented flaw with associated axial conponent.
- 4) Reference 9.
4 4 6 4
XCP-34-101 A.3 Revision 0 nutech
1 1
I 1 I
[
APPENDIX B APPLIED STRESSES AT FLAWED WELD LOCATIONS
[
[
[
'l XCP-34-101 B.O Revision 0 nutech
Table B.1 APPLIED AXIAL STRESSES AT 4" TO 22" NPS FLAWED WELD LOCATIONS
- Weld ID Stress (psi) 2332-RR-4A-1 6663 2B32-RR-4A-ll 7897 2B32-RR-4B-1 6630 2B32-RR-4B-ll 7988 2B32-RR-12-AR-A2 7749 2B32-RR-12-AR-A3 8493 2B32-RR-12-AR-B2 7253 2B32-RR-12-AR-B3 7973 2B32-RR-12-AR-Cl 10851 2B32-RR-12-AR-C2 7771 2B32-RR-12-AR-C3 7604 2B32-RR-12-AR-C4 11298 2B32-RR-12-AR-D1 7407 2B32-RR-12-AR-D4 9040 2B32-RR-12-AR-E2 7267 2B32-RR-12-AR-E3 7501 2B32-RR-12-AR-E4 10069 2832-RR-12-BR-F2 6917 2832-RR-12-BR-F3 7219 2B32-RR-12-BR-F4 8655 2B32-RR-12-BR-G1 7483 I
XCP-34-101 B.1 Revision 0 l
nutech
Table B.1 APPLIED AXIAL STRESSES AT 4" TO 22" NPS FLAWED WELD LOCATIONS *
(Concluded)
Weld ID Stress (psi) 2B32-RR-12-BR-G2 7306 2832-RR-12-BR-G3 7442 2B32-RR-12-BR-G4 10260 2832-RR-12-BR-H2 7758 2B32-RR-12-BR-H4 11077 2B32-RR-12-BR-J2 7374 I 2B32-RR-12-BR-J3 7598 2B32-RR-12-BR-K2 7454 2B32-RR-12-BR-K3 8205 2B32-RR-22-AM5 8699 2832-RR-22-BM1 6635 I
I
- Stress = internal pressure + seismic + deadweight stresses (Reference 5) in the axial direction.
1 I
I I
XCP-34-101 B.2 I Revision 0 g nutech
Table B.2 APPLIED AXIAL AND HOOP STRESSES AT 28" NPS FLAWED WELD LOCATIONS Crack Growth Strength Evaluation (II Design Weld ID Stress (psi) Evaluation Stress (psi) (2) Stress'3) 2B32-RR-28-A4 9892 10702 15654 2B32-RR-28-A8 8947 9838 14270 2832-RR-28-A13 9302 10898 12367 2B32-RR-28-B3 8964 10195 15293 2832-RR-28-84 8671 9206 15523 2B32-RR-28-B5 7564 7989 15588 2832-RR-28-B11 8095 9487 14606 Notes:
f.l
+
- 1) Stress = internal pressure + deadweight + differ-ential thermal expansion stresses in i axial direction (Reference 5).
- 2) Stress = internal pressure + deadweight + seismic +
differential thermal expansion stresses in axial direction (Reference 5).
- 3) Stress = internal pressure stress in circumferential direction.
L i
XC P-34-101 B.3 Revision 0 nutech !"
APPENDIX C DESIGN VS. AS-BUILT OVERLAY DIMENSIONS - 1983 OVERLAYS BUILT-UP IN 1986 k,
t k
i XCP-34-101 C.0 i l'
Revision G '
4 nutech ,
L
i 1983 OVERLAY REPAIRS - DESIGN AND AS-BUILT INFORMATION 1
A >
8 450 MIN. "
TYP. p "1 , ,
o
]
( '
W//M//ffffAW////f/f/Mf/A,
-t WELD I
_Desicn Dimensions (in. ) As-Built Dimensions (in.)III l Weld ID A B t A+B t(2) 2B32-RR-12-BR-G4 2.25 (3) 0.27 3.569 0.402 I 2832-PR-12-BR-J2 j
2.25 2.25 0.27 5.175 0.343 p
2B32-RR-12-BR-J3 2.25 2.25 0.28
[ 4.684 0.305 !j, 2B32-RR-12-BR-K2 2.25 2.25 0.28 r 4.880 0.454 2832-RR-12-BR-K3 2.25 2.25 0.28 4.555 0.374 Notes:
- 1) Peference 10.
- 2) Less 0.10" for first layer as in Section 4.0.
- 3) Toe of overlay to remain minimum of 0.25" from maxinun extent of Inconel; length need not exceed stated "A" dimension.
XCP-34-101 C.1 Revision 0 nutech
~
J 4
t j '.
L 1
i" I
1
- I 1
4 1-
!II APPENDIX D
- t l t t.
1 DESIGN VS. AS-BUILT OVERLAY DIMENSIONS -
1986 OVERLAYS i
, li 1.
i b{
i 1
l l
i- .
I i
i l
i i.
i i
XCP-34-101 D.0 1
Revision 0 f
n I
nutech *
[
Detail Dasign Cimensions (in. ) As-Built Dimensions (in.)(6)
Weld ID Number A B t A+B t IOI
.I 2B32-RR-4A-1 D-1 1.0 0.133 (1) 1.734 0.217 2B32-RR-4A-ll D-1 1.0 (1) 0.133 1.771 0.198 2B32-RR-4B-1 D-1 1.0 (1) 0.146 1.964 0.298 2B32-RR-48-ll el 1.0 (1) 0.133 1.741 0.207 2832-RR-12-AR-A2 D-2 2.25 2.25 0.25 4.475(7) 0.468 2B32-RR-12-AR-A3 D-2 2.25 2.25 0.29 4.742 0.42C 2B32-RR-12-AR-B2 D-2 2.25 2.25 0.25 4.550 0.320 2B32-RR-12-AR-B3 D-2 2.25 2.25 0.24 4.574 0.346 2B32-RR-12-AR-Cl D-3 2.25 (2) 0.31 2.692 0.477 2832-RR-12-AR-C2 D-2 2.25 2.25 0.27 4.956 0.347 2832-RR-12-AR-C3 D-2 2.25 2.25 0.27 4.859 0.346 2B32-RR-12-AR-C4 D-2 2.25 (3) 0.32 2.309 0.331 2832-RR-12-AR-D1 D-3 (2) 2.00 0.22 2.566 0.225 2B32-RR-12-AR-D4 D-2 2.25 (3) 0.26 3.250 0.574 2832-RR-12-AR-E2 D-2 2.25 2.25 0.28 4.728 0.329 2832-RR-12-AR-E3 D-2 2.25 2.25 0.27 4.500 0.348 2B32-RR-12-AR-E4 D-2 2.25 (3) 0.28 3.194 0.526 2B32-RR-12-BR-F2 D-2 2.25 2.25 0.25 4.535 0.345 2B32-RR-12-BR-F3 D-2 2.25 2.25 0.22 4.660 0.294 2B32-RR-12-BR-F4 D-2 2.25 (3) 0.26 2.953 0.314 2B3 2-RR-12-BR-G1 D-3 (2) 2.00 0.23 3.719 0.270 2B32-RR-12-BR-G2 D-2 2.25 2.25 0.22 4.810 0.294 2832-RR-12-BR-G3 D-2 2.25 2.25 0.27 4.537 0.405 1
XCP-34-101 D.1
, Revision 0
{ nutech
J Ebtail [bsign Dimensions (in. ) As-Built Dimensions (in.)(0)
Weld ID Number A B t A+B t IOI 2B32-RR-12-BR-H2 D-2 2.25 2.25 0.24 4.716 0.397 2832-RR-12-BR-H4 D-2 2.25 (3) 0.31 2.804 0.403 2B32-RR-22-AM-5 D-3 3.50 (4) 0.42 4.349 0.610 2B32-RR-22-BM-1 D-2 3.50 3.50 0.40 7.199 0.468 2B32-RR-28-A-4 D-2 4.0 4.0 2 Eayers 8.600 0.150 2B32-BR-28-A-8 D-4 4.25 (5) 2 Layers 5.099 0.143 2832-RR-28-A-13 D-4 4.5 (5) 2 Iayers 6.225 0.185 2B32-RR-28-B-3 D-2 4.25 4.25 2 Iayers 8.845 0.204 2B32-RR-28-B-4 D-2 4.25 4.25 2 Layers 9.340 0.211 2B32-RR-28-B-5 D-2 4.25 4.25 2 Iayers 9.210 0.119 2B32-RR-28-B-ll D-4 4.25 (5) 2 Layers 5.269 0.170 Notes:
- 1) Overlay extends to Weld-o-let.
I 2) Overlay extends as far as practical tcward Sweep-o-let but need not exceed stated "A" or "B" dim nsion.
lq 3) Toe of overlay to remain minimum of 0.25" frcm traximum
- l extent of Inconel; length need not exceed stated "A" dimension.
- 4) Overlay extends to cross.
- 5) "B" side is non-susceptible component, no overlay.
- 6) Reference 10.
- 7) As-built length 0.025" less than design judged to be acceptable.
- 8) Not including first layer thickness except for 28" welds.
i XCP-34-101 D.2 I Revision 0 nutech
1 k '
- i ... _ ,
, a e
/ / d e51 tV # ##lf#
l##AW!# isAshd I "" l t-D3 tail D-1 Datail D-2 A
, , ! 4$ 4 4HPe
[ "f, " e g
.I~
a 9'd??Wd6iT
, em 4 warro//rM//sMasiA*!'str/r////Mz///At
-e
"' l q ano Detail D-3 Detail 0-4 I
1 WELD OVET'IAY REPAIR DETAILS XCP-34-101 D.3 Revision 0 nutech
C' APPENDIX E i'
SHRINKAGE ANALYSIS - INPUT AND RESULTS l
e t
~
4 f
4 I
l XCP-34-101 E.0 '
} Revision 0 '
i
- nutech
i Table E.1 AXIAL SHRINKAGE MEASUREMENTS Weld ID Axial Shrinkage (in)(1) 2B32-RR-4A-1 N/A 2B32-RR-4A-ll N/A 2B32-RR-48-1 N/A 2B32-RR-4B-ll N/A 2B32-RR-12-AR-A2 0.304 2B32-RR-12-AR-A3 0.332 2B32-RR-12-AR-B2 0.225 2B32-RR-12-AR-B3 0.267 2B32-RR-12-AR-Cl 0.271 28 3 2-RR--12-AR-C 2 0.310 2B32 RR-12-AR-C3 0.274 2B32-RR-12-AR-C4 0,127 2B32-RR-12-AR-D1 0.086 2B32-RR-12-AR-D4 0.178 2B32-RR-12-AR-E2 0.357 2832-RR-12-AR-E3 0.308 2832-Rr-12-AR-E4 0.185 2B32-RR-12-BR-F2 0.281 2B32-RR-12-BR-F3 0.249 2B32-RR-12-BR-F4 0.158 2B32-RR-12-BR-G1 0,195 2B32-RR-12-BR-G2 0.374 1
XCP-34-101 E.1 Revision 0 l nutech
1 Weld ID Axial Shrinkage (in)(1) 2832-RR-12-BR-G3 0.280 2B32-RR-12-BR-G4 0.227(2) 2B32-RR-12-BR-H2 0.276 2B32-RR-12-BR-H4 0.168 2B32-RR-12-BR-J2 0.301(3) 2B32-RR-12-BF-J3 0.335(3) l 2B32-RR-12-BR-K2 0.269(3) 2832-RR-12-BR-K3 0.294(3) 2B32-RR-22-AMS 0.193 2B32-RR-22-BM-1 0.235 2B32-RR-28-A-4 0.080 2B32-RR-28-A-8 0.066 2B32-RR-28-A-13 0.048 2B32-RR-28-B-3 0.102 2B32-RR-28-B-4 0.068 2B32-RE-28-B-5 0.083 2B32-RR-28-B-ll 0.085 I (1) Reference 10 unless otherwise noted (2) 1983 shrinkage (Reference 3) j (3) 1983 plus 1986 shrinkages I
I -
I XCP-34-101 E.2 I, Revision 0 g nutech
3 Table E.2 UNFLAWED RECIRCULATION SYSTEM WELDS -
WELD OVERLAY SHRINKAGE STRESS Weld ID Stress (psi) 12-AR-Al 2199 12-AR-A4 4217 12-AR-B1 2416 I 12-AR-B4 7925 12-AR-D2 5031 12-AR-D3 4356 12-A4-El 7103 I 28-A3 452 28-A4 502 28-A6 631 28-A7 337 28-A9 34 28-A10 43 28-All 8 28-A12 54 117 28-A14 272 28-A15 346 3 28-A16 28-A17 297 1259 22-AM2 2031 22-AM3 E 22-AM4 1284 1238 22-AM6 0 22-AM1 2691 8 12-BR-F1 5442 12-BR-H1 2617 12-BR-H3 1699 12-BR-J1 3046 12-BR-J4 3568 12-BR-K1 2633
, 12-BR-K4 1097 28-B6 341 28-87 302 28-88 224 1 28-89 149 28-B10 127 28-B12 99 28-B13 83 28-B14 108 28-B15 157 28-B16 136 1 28-B17 1089 22-BM2 1629 22-BM3 1802 1 22-BM4 3174 XCP-34-101 E.3 Revision 0 l nutech
1 l
i !
4 1
M
- l-t
.I APPENDIX F INPUT TO NUTCRAK ANALYSIS
- t. .
Il il 4
.t l
a i
i r
XCP-34-101 F.0 :4 Revision 0 '
r nutech /
3 l
- 1. Check on Crack Growth Under Leak Barrier Weld Overlay Repairs i I
Crack growth correlation = 3.58 x 10-8 g 2.161 (Reference 11)
E Where da = incremental crack depth (inches) dt = incremental time (hours)
I K = stress intensity facter at crack tip (ksi M)
Assumed flaw: 24% x 360* circumferential Stress (internal pressure + deadweight + thermal stress at most highly stressed 28" flawed weld location) = 9892 psi E Weld overlay residual stress (28" pipe with leak barrier weld overlay):
% Through-wall g Stress (ksi)
U 6 12 11 0 24 -16 47 -19 61 -10 66 0 68 4 82 18 NUTCRAK internally calculates stress intensity factor at the crack tip, then calculates crack growth. Crack growth pre-diction is presented graphically in Figure 4.1. Allowable flaw depth was determined from References 1 and 2, with applied stress = 10898 psi from Appendix B.
XCP-34-101 F.1 I Revision 0 l nutech
- 2. Check on Crack Growth in the Presence of IHSI R idual Stresses Crack growth correlation h = 3.58 x 10-8 g 2.161 (Reference 11) 1 Where 1 da = incremental crack depth (inches) dt = incremental time (hours)
I K = stress intensity factor at crack tip (ksi M)
Assumed flaw: 10% x 360' circumferential in 12" (most highly stressed) pipe i Stress (internal pressure + deadweight + weld overlay shrinkage stress at most highly stressed unflawed location)
= 26378 psi i IHSI residual stress (12" pipe, Reference 12):
% Throuch-wall Stress (ksi) 0 -33 36 -31 54 0
- 64 20 80 29 100 1 NUTCRAK internal), ve.culates stress intensity factor at the crack t.1p, then calculates crack growth. Stress intensity factor at the crack tip was negative; therefore, no crack growth takes place.
.I XCP-34-101 F.2 Revision 0 I
l nutech .
i ATTACHMENT 2 TO SERIAL: NLS-86-158 (3859 MAT /pgp)
r GENER AL h ELECTRIC NUCl. EAR ENERG/ BUSINESS CPERATIONS GENERAL ELECTRIC CCMPANY
- 175 CURTNER AW.NUE
- SAN JOSE, CAUFCRNIA 95125 April 2, 1986 Chris Patterson Carolina Power & Light Highway 87 Southport, NC 28461
SUBJECT:
Fracture Mechanics Analysis of Brunswick Unit 2 Recirculation No==le-to-Safe End Weld Indications Two indications recently discovered by ultrasonic test (UT) inspection of the recirculation outlet (N1) nozzle-to-safe end welds in the Brunswick 2 reactor, have been evaluated. A summary of the evaluation l and the findings are reported herein along with an estimate on l acceptable flaw depths for the recirculation inlet (N2) nozzle-to-safe [
end welds.
Recirculation Outlet Nozzle (N1) Indications The two indications found in the 28 inch outlet noz=les were both located in the Inconel 182 weld butter, on the ID surface, and were axial in orientation. They were sized as being 0.25 inches deep by 0.30 inches long, and 0.25 inches deep by 0.25 inches long. A fracture mechanics evaluation was performed to determine if the flaws would meet safety margins for 12,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> of further operation considering additional IGSCC crack extension. Two separate analyses were performed:
P gs 2 Chris Patterson April 2, 1986
- 1. Assessment of the Indications in the Inconel Safe End k' eld An IGSCC crack growth analysis was performed on the measured indications and the final flaw si=e (after 12,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />) was compared to the ASME Code Section II acceptance Standards of Paragraph Ik'B-3640. In accordance with NRC SECY 83-267C requirements regarding the use of these acceptance standards for welds, the allowable a/t v'alues were adjusted by a factor of 2/3. The normal operation sustained hoop stresses at the location of the indications consist of 9 ksi pressure and approni=ately 70 ksi weld residual. Using a combined stress of 80 ksi, stress intensity factors were calculated by the method outlined in Appendix A to Section XI. Correlating the applied stress intensity factors to IGSCC crack growth
, data for Inconel 182, a crack growth analysis was performed.
After 12,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />, the indications were found to extend to a depth of 0.85 inch which is 41 of the 2.063 inch thickness.
Even considering a long crack (up to 5.3 in.) the allowable flaw depth per Table Ik'B-3441-3 is 75% of wall. Applying the 2/3 factor, the allowable a /t would be 50%, or 1.03 inch.
f The 0.35 inch final crack depch is well within this Code allowable.
' ' ,/ ,
Prgo 3 Chris Pattsrson April 2, 1986
- 2. Consideration of Potential Crack Extension into the Low Alloy Steel Nozzle 4
Evaluation of potential crack extension into the low alloy steel i o part of the nozzle safe end weld considers both fracture and ,
ductile failure modes. 'I i
(a) Linear Elastic Fracture Mechanics (LEFM) Assessment A critical flaw size analysis was perfor=ed assuming the axial indication to be through-wall, to determine the leak-before-break margin based on LEFM. Though IGSCC would not propagate into the low alloy steel no: le, the crack tip was conservatively assumed to be in the less tough low alloy steel. The stress intensity factors fer a longitudinally cracked 28 inch cylinder at various crack lengths were calculated and compared to the available crac'c arrest
'~
.. toughness of 100 ksi [in. ' It was f'ound that it would taka a through-wall crack 30 inches in length to exceed the arrest value.
This analysis demonstrates sizeable leak-before-break mr gin against unstable crack propagation. ,
(b) Limit Lead Assessment \
I s
A critical flaw size analysis was also performed for a 1 3 through-thickness axial flaw based on a , limit load failure.g This 4 type of failure corresponds to gross plastic yielding of the pipe (nozzle) ahead of the crack, and is controlled by the critical condition for axial cracks in a cylinder:
s hoop ' # flow
[s>b vhere, M=
1+1.61'f')
("a" is the crack half-length here)
Page 4 Chris Patterson April 2, 1986 For a hoop stress of 9 ksi and a flow stress of 61.3 ksi the critical flaw size was determined to be 56 inches. This analysis demonstrates substantial leak-before-break margin against unstable plastic yielding.
Based on the above analysis even if crack extension into low alloy steel no::le occurs a significant leak-before-break margin will be maintained.
Conclusion of Outlet Noz=le Evaluation 6
The results of the fracture mechanics analyses show that continued operation for at least 12,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> without repair is justifiable. The ASME Code Section XI safety margins would be maintained throughout this period. In addition, substantial leak-before-break margin against pipe as well as nozzle failure is assured.
Recirculation Inlet Safe End Weld Similar to the crack growth analysis performed on the outlet nozzle indications, a crack growth analysis for potential axial cracking in the 12 inch inlet nozzle inconel welds was perfor=ed to esti= ate the allowable flaw sizes as a function of further operating time.
Based on the IWB-3640 allowables, the results are shown in the attached figure for final inspection period flaw depths of 50% and 75% of the 0.875 inch wall. Large aspect ratios (.5 <a/t) were assumed for the analysis. The allowable flaw depths for 12000 hours of further op.eration may be less than UT capability of detection. However, the figure indicates that for an inspection period of 6000 hours0.0694 days <br />1.667 hours <br />0.00992 weeks <br />0.00228 months <br />, a 17% flaw would be acceptable.
Since UT inspection can detect approximately 10% of thickness, this would be a reasonable inspection period. An inspection period of 4000 hours0.0463 days <br />1.111 hours <br />0.00661 weeks <br />0.00152 months <br /> would allow flaws up to 27% of wall. Note that these inspection periods are based on meeting the allowable crack depths in Table IWB-3640-3 using conservative crack growth rates. In fact, using IWB-3642, it can be shown that through wall cracks can be tolerated while still maintaining the required ASME Code margin.
Pego 5 Chris Pettcrson April 2, 1986 LETM fracture mech'anics and-limit load esiculations were also performed
~
for the inlet nozzles assuming through wall axial cracks in the 12 inch diameter lov alloy steel. 'It was found that a crack length of 17 inches could be tolerated based on LEFM, and 23 inches based on a limit load
~
analysis. Thus there is considerable leak-before-break margin in the inlet nozzles as well.
We hope that this information for the inlet nozzles will be of help in assessing indications, should any be found, in y'our current inspections.
If you have any questions regarding either of the analyses performed, _
please contact us.
I Sincerely, h//h M. A. White Engineer V
4"S. Ranganath, Manager c
Structural Analysis Services Structural Analysis Services r (408) 925-2699 (408) 925-6825 J
. r .-. v.,. , , .,,,.n,_. ,,,,,,,n, , , _ , . . . . _ - - . . _ , . . - _ , ._.-..----,,.-,,..n._, ,-.,-- - , .- - , , , _ , . , _ ,
16000 , ,
t
. . t t 4 -
1 1 '
Est_t::i.s_t_ed -InsPe_c_r_t_on-Ferted . .
1 fer-Indieat-ions -in--the ~L-e-ieculation.
Y - < T ., i . ,- wm . i . e n w. v.na v,m i -
14000 ' 'x .
mu. ic.s.
6, .uo ,- -- 80",
. _I s *
\ 6 n . . s e . .. \ . . . . . .j I \ I t 3 a
N . +
t 6 x i .
. . x , .
. x . .
x ,
X 12000 . . _ _ x _ _ . . _ _ _ _ _ _ . . . . _ _ . _ _ . _ . . _ . . _ . _ _ . _ . . _ _ . . .
... . _ . _ __.___... . ...a . .
final ,
..n,y5 .. .
m . . _ .
..c...
,a . . . . . . . . _ . . _ _ . . . . . . _ . . _ _ . _ . . . . . . . . _ . .
- 10000 - .
o . _ . .__ _... _ ._ _.__ _ ._ _ __... 4 . ._ __......._.. ..
~ ~ - -
v .. = . _ _ - . . _ . . _ _ . . . . . .
n ..____
. _.= ,. .- ._.. - - _ _
It
. - _ . _-- _---\. -
o . _ . _ . . _ _ . _ . _ . . . . _ _ . . . . . . . _ . . _ . . . . .
a 8000 - . . . _ _ _ . . .s o . _ . . . . _ . . . ._ - _ . . . . . _ t g
$d . .. . . . . . . _. _ _ _ _ _ - _
- c ._
.i o . 3 .
_ . _ _ - - . final .~~~ -
- - - ~ ~ ~ ~ - --
.2 fd
. _ . . . . . _ ._.. . . _t.... 4....50._t.._ ... - - - _ - - - - - -
s, . . . . . ._.
a a c
o
__.____._J_._
y . . . . . .
O
______._____.._ ..._.._._ ..._.7 .
._ _ _ _ ._.t _ _ - - , . . ... __. _.. _.
1 .
.. .. 3 -
4000 - - -- -- -
I
_..__.L. . . . . -.. .
. - _ . ..j
= =. i
___{
t __
._ __ .- ....___...L -- ..._.. ...
. _ . . . _.-~. . .. I
_ _.:. _ . .._____ _ ..__.._ ._ _. . _ . . . . _ .. _ t ._ . . . . _ . . !
l ... - _ . _ . . . _ . _ _ __ ..____ _ _ L... ..._ _- ...4
_ _ _ . q ,
9
___ - y .... _ . %
2000 !,
, t .
.!i
._.._.__ . i .. ;
_. I .
- . 6
_.L__._... ! *6* . . . . .y
. ; . - g ni pg
' *
- 3
- I e I ,. ,,;_ e i It.' .,__ . q 7
. ay ,
._i
_.. * , e ,i e t . e f
4 _.
.: t fjs -
M
- p. -
fg.;..H . . . ..;i 0 .05 .10 .15 .20 .25 .'3 0 Current Indication Depth (Inches)
_ _ _ _ _ _ _ _ _