ML061580443
| ML061580443 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 05/31/2006 |
| From: | Spina J Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LTR-CI-06-26-NP, Rev 0 | |
| Download: ML061580443 (30) | |
Text
James A. Spina Calvert Cliffs Nuclear Power Plant, Inc.
Vice President 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 410.495.4455 410.495.3500 Fax Constellation Energyl Generation Group May 31, 2006 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit No. 1; Docket No. 50-317 ASME Code Section XI Flaw Evaluation of Dissimilar Metal Weld Flaws Identified by Ultrasonic Testing Inspections using ultrasonic examination (UT) methods performed at Calvert Cliffs Nuclear Power Plant (CCNPP) Unit 1 during the 2006 Refueling Outage detected indications in three Reactor Coolant System pressure boundary dissimilar metal (DM) welds.
Two of the indications exceeded the acceptance standards of the American Society of Mechanical Engineers (ASME) Boiler & Pressure Vessel Code (B&PV),Section XI, Subsection IWB Sub-article IWB-3 500. The attached flaw evaluation is provided for the Nuclear Regulatory Commission review in accordance with ASME B&PV Code Section XI requirements contained in IWB-3640, "Evaluation Procedures and Acceptance Criteria for Austenitic Piping."
Indications which exceeded the IWB-3500 standards were found in the 12 inch hot leg surge nozzle to safe end weld [12CC2-1001(W13)]
and the 2 inch hot leg drain nozzle to safe end weld
[2CC9-1007(W1)].
A stress improvement mitigation technique (Mechanical Stress Improvement Process-MSIP) has been performed at each of these locations.
This method induces compressive stresses on the inside pipe wall where the indications are located. These post-MSIP residual stresses, when added to the normal operating pressure and piping loads, mitigate any further crack propagation due to primary water stress corrosion cracking.
To ensure the mitigation was technically sound and acceptable, an analytical flaw evaluation was carried out for each nozzle, using the rules of ASME B&PV Code Section XI, Sub-article IWB 3600, to determine if the as-found flaws are within the Code maximum allowable limits. The evaluation is consistent with the guidelines of MRP-139, Primary System Piping Butt Weld Inspection and Evaluation Guideline.
The ultrasonic examinations were performed by qualified Performance Demonstration Initiative DM weld examiners and inspection procedures. The flaw evaluation results (Attachment 1) demonstrate that the plant remained in an operable condition prior to discovery of the subject flaws.
4ocpy
Document Control Desk May 31, 2006 Page 2 Should you have questions regarding this matter, please contact Mr. L. S. Larragoite at (410) 495-4922.
Very truly yours, JAS/MJY/bjd
Attachment:
(1)
Westinghouse Document LTR-CI-06-26-NP, Revision 0, dated March 17, 2006, (Reclassified Westinghouse Non-Proprietary Class 3, March 24, 2006) cc:
P. D. Milano, NRC S. J. Collins, NRC Resident Inspector, NRC R. I. McLean, DNR
ATTACHMENT (1)
Westinghouse Document LTR-CI-06-26-NP, Revision 0, dated March 17,2006, (Reclassified Westinghouse Non-Proprietary Class 3, March 24, 2006)
Calvert Cliffs Nuclear Power Plant, Inc.
May 31, 2006
Evaluation of As-found Flaws in Surge, Drain and Relief Valve Nozzle Safe-end Welds at Calvert Cliff Unit I during March 2006 Outage Introduction In-service inspections performed at Calvert Cliffs Unit 1 during the 2006 Refueling Outage detected an indication in three (3) reactor coolant system (RCS) pressure boundary dissimilar metal welds. Two of the indications exceed the acceptance standards of ASME Boiler &
Pressure Vessel Code Section XI, Subsection IWB Article IWB-3500. Indications which exceed the IWB 3500 standards were found in the 12 inch hot leg surge nozzle to safe end weld (12CC2-1001(W13)) and the 2 inch hot leg drain nozzle to safe-end weld (2CC9-1007(VVI)).
These two welds have indications on the inside surface of the nozzle safe-ends which are circumferential in orientation. An axial indication was detected in the pressurizer relief valve to safe-end weld (4CC10-1006(WV)). The size of this indication is within the acceptable limits of Article IWB-3500. All three flaws are suspected to be caused by primary water stress corrosion cracking (PWSCC).
A stress improvement mitigation technique called "Mechanical Stress Improvement Process" (MSIP) has been performed at each one of these locations during the current outage. This method induces compressive stresses on the inside surface and inner wall where the indications are located.
These post-MSIP residual stresses, when added to the normal operating pressure and piping loads, mitigate any further crack propagation due to PWSCC.
To ensure that such a mitigation is technically sound, an analytical flaw evaluation was carried out for each nozzle, using the rules of ASMECode Section XI, Article IWB 3600, to determine if the as-found flaws are within the Code maximum allowable. Fatigue and PWSCC crack growth was considered and found to be negligible because of the compressive stresses over the entire length of the flaw. The evaluation used ASME Section XI, and is consistent with the guidelines of MRP-1 39 [Reference 8].
The as-found indication sizes determined from the UT evaluation sheets by WesDyne (Reference 1) were used directly in the flaw evaluation described herein.
Westinghouse Electric Company (WEC) with AEA Technology Engineering Services (AEA) performed the MSIP at Calvert Cliffs. AEA's residual stress analyses results are detailed in References 2a through 2c.
These reports list the through-wall residual stresses at the indications in the post-MSIP condition as well as those at the normal operating condition after the MSIP has been performed. These stresses are superposed on to the piping stresses due to thermal dead weight and seismic loads. For the surge-line, stratification piping loads were also considered in the flaw evaluation.
Westinghouse Proprietary Class 3 Page 1 of 27
Geometry, Piping Loads and Material Properties Nozzle dimensions at the safe-end welds were derived from the WEC drawings and listed in Table 1. This table also lists the structural factors, allowable stress and the material flow stresses assumed in the analysis.
Table 2 lists the indication dimensions as detected by WesDyne and reported in Reference 1.
Piping loads used in the analysis are from the Westinghouse Electric stress analysis reports (Reference 7) and listed in Table 3 for the surge nozzle and in Table 5 for relief nozzle. Drain nozzle loads are supplied to WEC by Constellation (Reference 6) and are listed in Table 4.
Corresponding stresses for these nozzles are listed in Table 6 through 8.
Flaw Evaluation A plot of the as-found indication depth and aspect ratios along with the ASME Code Subsection IWB limits is shown in Figure 1. This figure indicates that the flaws in the surge and drain nozzles exceed the allowable whereas the relief nozzle indication is within the allowable limit.
When the as-found indications exceed the allowable values in Subsection IWB-3500,Section XI requires one to consider the analysis procedures as specified in Subsection IWB-3600. This leads to the analytical techniques in Appendix C Article C-5321 for circumferential flaws and in Article 0.5420 for axial flaws. One can also use the tables G5310-1 through 0-5310-4 for circumferential flaws. Here the former approach was chosen.
The Imit load approach in the ASME Code Section XI, Division I Appendix C (Reference 3) applies to the flaw evaluation at the nozzle safe-end welds, because the Alloy 182 weld metal has extremely high fracture toughness, typical of stainless steel base metal.
Flaw definitions using the terminology of the ASME Code are shown below.
FIG. C-4310-1 CIRCUMFERENTIAL FLAW GEOMETRY (from ASME Section Xl Division I Appendix C)
Westinghouse Proprietary Class 3 Page 2 of 27
R44 FIG. C-4310-2 AXIAL FLAW GEOMETRY (from ASME Section XI Division 1 Appendix C)
Surge Nozzle Flaw Evaluation Using the equations in the ASME Code Appendix C, allowable bending stresses were computed as a function of the flaw depth to thickness ratio. These results are plotted in Figures 2 and 3 for service level A and C conditions, respectively. Here, for the given flaw length and the applied membrane stress, the Code allowable bending stress limit is plotted as a function of the flaw depth to thickness ratio along with the actual as-found flaw parameters. These figures clearly show that the indication is within the acceptable limits for both the levels A and C piping loads, with and without surge-line flow stratification.
Another way to look at the flaw evaluation is the allowable stress ratio as a function of the flaw depth to thickness ratio, as shown in Figures 4 and 5. These figures show the allowable stress ratio (sm+sb)/sf prescribed in the Code Tables C-5310-1 and C-5310-3 as a function of the flaw depth to thickness ratio. These Code values were interpolated for the actual aspect ratio as detected by WesDyne UT examination. These figures also show that the as-found flaws were acceptable during pre-outage operation prior to the MSIP repair, demonstrating that the plant remained In an operable condition even before the indications were known.
Figures 6 and 7 show the pre-as well as post-MSIP through-wall stresses at the flaw location with and without stratification loads, respectively.
These figures show that the post-MSIP stresses, when superposed with the piping loads, are clearly compressive over approximately 1 inch through the wall from inside surface. This compressive stress region far exceeds the as-found depth of 0.4 inch, thereby indicating that the MSIP repair will arrest any further PWSCC growth.
As a further note, the total post-MSIP stresses are linearized as in Figure 8 and 9 and crack tip stress intensity factors (SIF) are computed using the influence coefficients available in Reference 5. Results of this evaluation are shown in Table 9. For the as-found flaw depths, SIFs are clearly negative even for the most severe loading condition stratification loads, further reinforcing the conclusion that the MSIP will mitigate any future PWSCC growth.
Westinghouse Proprietary Class 3 Page 3 of 27
-A Drain Nozzle Flaw Evaluation The circumferential indication in the drain nozzle safe-end was also evaluated using the same procedure as for the surge-line. Applying the analytical equations in Appendix C, allowable bending stresses were computed as a function of the flaw depth ratio for the as-found flaw length and the applied membrane stress. Results of the allowable bending stresses are plotted in Figure 10 for Level A and in Figure 11 for Level C conditions. The actual as-found indication parameters, also plotted in Figures 10 and 11, clearly show that the indications are well within the limits of the Code requirements. Again, this shows that the plant was in an operable condition even before the Indication was known.
The drain nozzle indication was also evaluated for the post-MSIP conditions using the residual stresses from AEA reported in Reference 2b. Figure 12 shows the distribution of the through-wall stresses in pre-and post-MSIP conditions. The post-MSIP stresses were superposed with the stresses from the piping loads and linearized as shown in Figure 13. These linearized stresses were used in computing the stress intensity factor (SIF) as a function of flaw size, and the results are listed in Table 10. The crack tip SIF was computed to be negative for the depth of the as-found indication, indicating that it is in a compressive zone in the post-MSIP stress field, assuring the mitigation process was effective and will mitigate any future PWSCC growth.
Relief Valve Nozzle Flaw Evaluation The axial indication in the relief valve nozzle safe-end was also evaluated using the analytical procedure available in Appendix Q Article C-5420. Maximum Code-allowable hoop stresses were computed as a function of the depth to thickness ratio for the as-found indication. Results of the allowable stresses are plotted in Figure 14 for Level A and in Figure 15 for Level C conditions. The actual as-found indication parameters, also plotted in these figures, clearly show that the pre-outage flaws are well within the limits of the Code requirements, again demonstrating that the plant was in an operable condition even before the indication was known.
The relief nozzle flaw was also evaluated for the post-MSIP conditions using the residual stresses reported in Reference 2c. Figure 16 shows the distribution of the through-wall stresses in pre-and post-MSIP conditions. The post-MSIP stresses were linearized as shown in Figure 17, These linearized stresses were used in computing the SIFs as a function of flaw size, and the results are listed in Table 11. Analytical influence coefficients available in Reference 4 were used in the evaluation. The crack tip SIF was again computed to be negative for depth of the as-found indication, for both level A and Level C conditions indicating that it is in a compressive zone in the post-MSIP stress field and demonstrates that the mitigation process was effective and will mitigate any future PWSCC growth.
Summary and Conclusions Both the circumferential indications detected in the surge-line and the drain-line nozzle safe-ends on the hot leg side of the Calvert Cliffs Unit I RCS pressure boundary were found to be acceptable and within the allowable limits of the ASME Section XI Division I Subsection IWB Article IWB-3600 and Appendix C requirements. These indications were found to be acceptable for both the normal load Level A and the faulted load Level C cases in the pre-outage operating condition, thus demonstrating that the plant was in an operable condition at all times with respect to the indications.
An evaluation of the as-found indications with the post-MSIP through-wall stresses indicates that the indications are well within the compressive region on the inside surface, thus assuring that the MSIP process will mitigate any further PWSCC growth during future operation.
Westinghouse Proprietary Class 3 Page 4 of 27
The axial indication found in the pressurizer relief nozzle safe-end is within the ASME Code limit for the pre-outage loading condition. The post-MSIP through-wall stresses in the nozzle also indicate that the indication is also well within the compressive zOne which assures the mitigation process was effective.
References:
- 1. Letter from Bernard C. Rudell of Constellation Energy to Edward A. Ray of Westinghouse Electric Co., "Flaw Evaluation of Calvert Cliff Unit I Reactor Coolant System Pressure Retaining Welds", dated February 27, 2006.
- 2. AEA Technology Engineering Services, Inc. Reports prepared for Westinghouse Electric Company, LLC:
a) "Mechanical Stress Improvement Process (MSIP) Calvert Cliffs Unit I RCS Hot Leg Surge DM Weld 12CC2-1001 (W13) MSIP Flaw Evaluation", Report No.
4205-6-001, dated 3/8/06.
b) "Mechanical Stress Improvement Process (MSIP) Calvert Cliffs Unit I Hot Leg Drain Nozzle DM Weld 2CC9-1007 (W-1) MSIP Flaw Evaluation", Report No.
4205-6-002, dated 3/8/06.
c) "Mechanical Stress Improvement Process (MSIP) Calvert Cliffs Unit I Relief Valve Nozzle DM Weld 4CCIO-1006 (W-1) MSIP Flaw Evaluation" Report No.
4205-6-003, dated 3/8/06.
- 3. ASME Section XI Division 1 a) Non-mandatory Appendix C on "Evaluation of Flaws in Piping", 1998 Edition and 2004 Edition.
b) Non-mandatory Appendix A on "Analysis of Flaws", 1998 Edition and 2004 Edition.
- 4. I.S. Raju and J.C. Newman, Jr., "Stress-Intensity Factor Influence Coefficients for Internal and External Surface Cracks in Cylindrical Vessels", pages 37-47, published in ASME PVP Volume 58,1982.
- 5. S. Chapuliot, M.H. Lacire and P. Le Delliou, "Stress Intensity Factors for Internal Circumferential Cracks in Tubes over a Wide Range of Radius over Thickness Ratios",
ASME PVP Volume 365, 1998.
- 6. Letter from Constellation Energy to Westinghouse Electric Co on Drain Nozzle Loads, Letter No. DE06302, dated March 14, 2006.
- 7. Westinghouse Electric Company Reports a) "Addendum to the Analytical Report for Baltimore Gas & Electric Power Company Piping C.E. Contract Nos. 72467/73467", dated April 1982.
b) "Project Specification for Reactor Coolant Pipe and Fittings for Calvert Cliffs Units I
& 2", Design Specifications No. 8067-31-5, Revision 18, dated 5/21/04.
c) "Addendum to the Pressurizer Analytical Report for Baltimore Gas & Electric Company Calvert Cliffs Units I and 2", Design Report No. B-PENG-DR-001, Revision 00, dated 3/29/95.
- 8. Material Reliability Program; Primary System Piping Butt Weld Inspection and Evaluation Guideline (MRP-139) 1010087, Final, July 14, 2005.
Westinghouse Proprietary Class 3 Page 5 of 27
Table 1: Geometry and Design Data (not including cladding)
Parameter Surge Drain Safety units Outside diameter 12 3/4 27/8 6 1/16 inch Inside diameter 10 1/8 21/8 3 7/16 inch Wall thickness 1.313 0.375 1.313 inch Structural Factor-membrane-Level A 2.7 2.7 2.7
-Bending - Level A 2.3 2.3
- Membrane-Level C 1.8 1.8 1.8
-Bending-Level C 1.6 1.6 2
Flow stress 52.5 52.5 52.5 ksi Table 2: Ultrasonic Examination Flaw Dimensions Parameter Surge Drain Relief units Depth 0.4 0.1 0.1 in Length 2.4 0.45 0.6 in Thickness 1.6 0.54 1.3 in Flaw orientation Circ Circ.
Axial
______1 Table 3: Surge Nozzle Piping Loads Load case Fx Fy (axial)
Fz Mx (bend)
My Mz (bend)
(kip)
(in-kip)
Upset (DW+Th+OBE) 17 9
28 277 765 329 Faulted (DW+Th+SSE) 22 13 32 507 1008 559 Max. Strat.
-2.09
-2.76
-16.86
-2274 1051 65 Upset + Strat.
19.09 11.76 44.86 2551 1816 394 Faulted + Strat.
24.09 15.76 48.86 2781 2059 624 Table 4: Drain Nozzle Piping Loads Westinghouse Proprietary Class 3 Page 6 of 27
Table 5: Relief Nozzle Piping Loads Table 6: Surge Nozzle Axial Stresses Load Case Sm Sb Sm+Sb Remarks (ksi)
(ksi)
(ksi)
Pressure 3.841 0
3.841 DW+Th+OBE 0.191 3.509 3.700 Combined with DW+Th+SSE 0.276 6.157 6.433 Post-MSIP+NoP P+DW+Th+OBE 4.032 3.509 7.541 For Pre-MSIP P+DW+Th+SSE 4.117 6.157 10.274 Evaluation DW+Th+OBE+Strat 0.249 21.057 21.307 Combined with DW+Th+SSE+Strat 0.334 23.251 23.585 Post-MSIP+NoP P+DW+Th+OBE+Strat 4.091 21.057 25.148 For Pre-MSIP P+DW+Th+SSE+Strat 4.176 23.251 27.427 Evaluation Table 7: Drain Nozzle Axial Stresses Load Case S,
Sb S,+Sb Remarks (ksi)
(ksi)
(ksi)
Pressure 2.709 0
2.709 DW+Th+OBE 0.147 9.784 9.932 Combined with DW+Th+SSE 0.158 10.592 10.749 Post-MSIP+NoP P+DW+Th+OBE 2.857 9.784 12.641 For Pre-MSIP P+DW+Th+SSE 2.867 10.592 13.459 Evaluation Table 8: Relief Valve Nozzle Pre-MSIP Hoop Stress Westinghouse Proprietary Class 3 Page 7 of 27
Table 9: Surge Nozzle Post-MSIP Crack Tip Stress Intensity Factors (from Reference 5, et. Al. 1998, Tables 3 & 4, a/c = 1/4, a/t = 0.4, t/Ri = 1/5)
Post-MSIP Post-MSIP Parameter
+Nop+Piping
+Nop+Piping units No Strat.
+Strat.
Through-wall membrane 4.378 21.984 (ksi)
Through-wall bending 46.402 46.402 (ksi)
Kltot
-36.21
-13.72 (ksivin)
Table 10: Drain Nozzle Post-MSIP Crack Tip Stress Intensity Factors (from Reference 5, et. Al. 1998, Tables 3 & 4, a/c = 1/4, a/t = 0.4, t/Ri = 1/5)
Post-MSIP Parameter
+Nop+Piping units (No Strat)
Through-wall membrane 6.882 (ksi)
Through-wall bending 64.384 (ksi)
Ktot 1
-27.74 (ksivin)
Table 11: Relief Nozzle Post-MSIP Crack Tip Stress Intensity Factors (from Reference 4, Table 2, a/c = 0.2, a/t = 0.2, t/Ri = 0.25)
Path 1 Path 2 Parameter Post-MSIP Post-MSIP units
+Nop+Piping
+Nop+Piping Through-wall membrane
-25.948 1.771 (ksi)
Through-wall bending 36.262 52.714 (ksi)
Kiot
-32.49
-25.42 (ksivin)
Westinghouse Proprietary Class 3 Page 8 of 27
pppppp,-
LTR-CI-06-26 Checklists, Page 9 of 27 0.5 0.4 0.3 15 a) 0.2 0.1 0.1 0
10 20 30 40 50 60 Flaw Depth Ratio aft (%)
Figure 1: Allowable Flaw Depths per ASME Section Xl Division 1 Subsection IWB Table IWB 3514-2 70 Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 10 of 27 C.,
0, C',
CA 4)
U, 0)
C
- 0 C
4) 4, 4) 0 bu I
I Allow.bend.stress w/o stratification
-- I-Applied bend.stress w/o stratification Allow.bend.stress with stratification Applied bend.stress with stratification 40O 30 20-10-0 0
0.1 0.2 0.3 0.4 0.5 Flaw Depth/wall thickness Ratio (alt) 0.6 0.7 0.8 0.9 H,
Figure 2: Hot Leg Surge Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratios-Level A Condition (Allowable bending stresses with & w/o stratification are almost identical and hence overlap in the above graph)
Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 11 of 27 50 An S30 20 FC 10 10 Allow. bend.stress w/o stratification
- -I--
Applied bend.stress w/o stratification Aliowebend.stress with stratification At ~-- Applied bend.stress with stratification A
0 0.1 0.2 0.3 0.4 0.5 Flaw Depth/wall thickness Ratio (a/t) 0.6 0.7 0.8 0.9 Figure 3: Hot Leg Surge Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratios-Level C Condition (Allowable bending stresses with & w/o stratification are almost identical and hence overlap in the above graph)
Westinghouse Proprbtary Class 3
MOM LTR-CI-06-26 Checklists, Page 12 of 27 0.8 0.7 0.60 0.5 0.4 0.3 Allowable Depth Ratio alt Allowable aft Flaw Length Ratio LIPI*D 0
C)
II 0.5 Figure 4: Hot Leg Surge Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratios - Level B Condition a) Allowable Flaw Depth Ratios vs. Stress Ratio and Flaw Length Ratio Westinghouse Proprtary Class 3
LTR-CI-06-26 Checklists, Page 13 of 27 I
0 0
0 0
m0 tU 0
"0
-I 0.
0.J
- " 0.
J0 U)*0 t' 0.
.0I Allowable a/t at as-found I/circ.
.9
- Applied stress ratio w/o stratification
-- Applied stress ratio with stratification
.8 -
.7-
.6
.5-
.4-3.
1 0.
0.
0.
0.0 0.1 0.2 0.3 0.4 0.5 Flaw Depth/wall thickness Ratio (a/t) 0.6 0.7 0.8 Figure 4: Hot Leg Surge Nozzle Safe-end Pre-MSIP Stress Ratio vs. Flaw Depth Ratio-Service Level A b) Allowable Flaw Depth Ratio vs. Stress Ratio Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 14 of 27 0.8 0.7 0.6 0.5 0.4 Allowable Depth Ratio 0.3at M0.7-0.8 110.6-0.7 M 0.5-0.6 M 0.4-0.5 00.3-0.4 30.2-0.3 110.1-0.2 m 0-0.1 Allowable a/t Flaw Length Ratio LIPI*D 0.5 =0.9 Figure 5: Hot Leg Surge Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratio vs. Stress Ratio - Level C Condition a) Allowable Flaw Depth Ratios vs. Stress Ratio and Flaw Length Ratio Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 15 of 27 C-0 0
E.2 0
u,
+
E 0
(.
U)
U) 1.0 I
1
-'*"AIIowable a/t at as-found I/crc.
0.9 0 I1-- Applied stress ratio w/o stratification 0..8 Applied stress ratio with stratification 0.8 0.7 0.6 A
0.5 0.4 0.3 0.2 0.1 0t i
I
______I______
______i I
_______I
- 0. V 0.0 0.1 0.2 0.3 0.4 0.5 Flaw Depth/wall thickness Ratio (a/t) 0.6 0.7 0.8 Figure 5: Hot Leg Surge Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratio vs. Stress Ratio - Level C Condition b) Allowable Flaw Depth Ratio vs. Stress Ratio Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 16 of 27 80 60 40 20 U)
U) 0
-20
-40
-60 0
0.2 0.4 0.6 0.8 1
1.2 1.4 1.6 Wall Depth from ID (in) 1.8 Figure 6: Hot Leg Surge Nozzle Safe-end Pre-and Post-MSIP Through-wall Axial Stress Distribution, No Stratification Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 17 of 27 80 I
X Cu 2'
0 0.2 0.4 0.6 0.8 1
1.2 1.4 1.6 Wall Depth from ID (in) 1.8 Figure 7: Hot Leg Surge Nozzle Safe-end Pre-and Post-MSIP Through-wall Axial Stress Distribution, with Stratification Westinghouse Proprbtary Class 3
r LTR-CI-06-26 Checklists, Page 18 of 27 CI) 4G)
X 0
80 I
1 1 l Pre-MSIP Upset Tot No strat
-Post-MSIP +Nop +Piping (No Strat) Axial Stress Post-MSIP Linearized membrane 60 Post-MSIP Linearized Total
-As-found indication depth 40-0 20-20-40 -W-
-60 0
0.2 0.4 0.6 0.8 1
Wall Depth from ID (in) 1.2 1.4 1.6 1.8 Figure 8: Hot Leg Surge Nozzle Safe-end Post-MSIP Linearized Through-wall Axial Stress Distribution, No Stratification Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 19 of 27 80 60 40 20 (I,
cj, i
0) 0 I-Pre-MSIP Upset Tot w/strat Post-MSIP +Nop +Piping +Strat. Axial 0,*
.-..Post-MSIP Linearized membrane
'=Post-MSIP Linearized Total As-found indication depth 0
2..
1...j 0
-20
-40
-60 0
0.2 1.8 Wall Uepth trom IU (in)
Figure 9: Hot Leg Surge Nozzle Safe-end Post-MSIP Linearized Through-wall Axial Stress Distribution, with Stratification Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 20 of 27 60 50 40 4) 30 rn 10 20 Allow. bend.stress A - -Applied bend.stress 0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0,9 Flaw Depth/wall thickness Ratio(a/t)
Ho Figure 10: Hot Leg Drain Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratios - Level A Condition Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 21 of 27 CO 4)
Allow.bend. stress A - - Applied bend.stress 50 40 30-20 10 0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Flaw Depth/wall thickness Ratio(a/t)
Ho Figure 11: Hot Leg Drain Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratios - Level C Condition Westinghouse Proprbtary Class 3
Checklists, Page 22 of 27 80 T
i 604
'Pre-MSIP Upset Tot Post-MSIP Axial Stress Post-MSIP +NoP Axial Stress Post-MSIP Total Axial Stress As-found Flaw Depth Un (o
2 40-20 0- -60
-80 0
0.1 0.2 0.3 0.4 Wall Depth from ID (in) 0.5 0.6 0.7 Figure 12: Hot Leg Drain Nozzle Safe-end Pre-and Post-MSIP Through-wall Axial Stress Distribution Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 23 of 27 80 60 40 20 0) 0)&0 G)
C',
0) 0 I-0
-20
-40
-60
-80 Post-MSIP membrane
'"Post-MSIP Total Axial Stress
-. -Post-MSIP Linearized Membrane
"=="
Post-MSIP Linearized Total e
-As-found indication depth
...........................0 000 0
0.1 0.2 0.3 0.4 Wall Depth from ID (in) 0.5 0.6 0.7 Figure 13: Hot Leg Drain Nozzle Safe-end Post-MSIP Linearized Through-wall Axial Stress Distribution Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 24 of 27 40 Allowable stress
Applied hoop stress 30 4
1
.4 1
.4 L
I 42)
CL o 20 0
10 0
l0 A
0.3 0
0.1 0.2 0.4 0.5 Flaw Depth/wall thickness Ratio (a/t) 0.6 0.7 0.8 0.9 Figure 14: Pressurizer Relief Nozzle Safe-end Pre-MSIP Allowable Flaw Depth Ratios Westinghouse Proprbtary Class 3
4.
LTR-CI-06-26 Checklists, Page 25 of 27 Co
'a O)
-o Cu 60 1
AIlowable Hoop stress A
Applied Hoop stress 50 40 30-20 10 0-0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Flaw Depth/wall thickness Ratio (a/t)
Pi Figure 15: Pressurizer Relief Nozzle Safe-end Pre-MSI P Allowable Flaw Depth Ratios, Service Level C Westinghouse Propritary Class 3
LTR-CI-06-26 Checklists, Page 26 of 27 60 40 20 0
Z5 0
0 F-
-20
-40
-60 0
0.2 0.4 0.6 0.8 1
1.2 Wall Depth from ID (in) 1.4 Figure 16: Pressurizer Relief Nozzle Safe-end Pre-and Post-MSIP Through-wall Hoop Stress Distribution, Paths 1 & 2 Westinghouse Proprbtary Class 3
LTR-CI-06-26 Checklists, Page 27 of 27 60 U) 0 00 0.r 0
0 0
0.2 0.4 0.6 0.8 1
1.2 Wall Depth from ID (in) 1.4 Figure 17: Pressurizer Relief Valve Nozzle Safe-end Post-MSIP Linearized Through-wall Hoop Stress Distribution Westinghouse Proprbtary Class 3