ML072250407

Supplement to Request for Relief from ASME Section XI Code Requirements for Repair of Service Water Pipe

ML072250407
Person / Time
Site:	Palisades
Issue date:	08/10/2007
From:	Schwarz C Entergy Nuclear Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML072250407 (26)

Text

Entergy Nuclear Operations, Inc.

Palisades Nuclear Plant 27780 Blue Star Memorial Highway Covert, MI 49043 August 10,2007 10 CFR 50.55a U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Palisades Nuclear Plant Docket 50-255 License No. DPR-20 Supplement to Request for Relief from ASME Section XI Code Requirements for Re~air of Service Water Pipe

Dear Sir or Madam:

On July 31, 2007, Entergy Nuclear Operations, Inc. (ENO) submitted a relief request from ASME Section XI Code requirements for repair of a Palisades Nuclear Plant service water pipe. Enclosure 3 of the relief request letter contained a calculation of the service water piping flaw evaluation and flaw growth analysis. EN0 subsequently discovered that the calculation was not the final calculation. The final calculation is provided herein as Enclosure 1. This final calculation replaces the one submitted earlier on July 31, 2007. The final calculation applied additional bending loads (moments) resulting in a change to the allowable circumferential flaw size from 35.87 inches to 25.58 inches. The allowable axial flaw size was not affected. The overall conclusion of the calculation was also not affected.

In parallel with the development of the request for relief, EN0 began work on a permanent repair plan for the subject service water pipe. As suggested during conference calls with the NRC regarding this relief request, EN0 is aggressively working to develop and implement the permanent repair plan on pace for completion during the upcoming 2007 refueling outage. EN0 will provide updates on the progress of the permanent repair plan. If and when it is determined that the repair plan will be fully implemented in the 2007 refueling outage, the relief request will be withdrawn.

Document Control Desk Page 2 Summary of Commitments This letter contains no new commitments and no revision to existing commitments.

-her J. ~c%w&z Site Vice President Palisades Nuclear Plant Enclosure (1 )

CC Administrator, Region Ill, USNRC Project Manager, Palisades, USNRC Resident Inspector, Palisades, USNRC

ENCLOSURE I SERVICE WATER PIPING FLAW EVALUATION AND FLAW GROWTH ANALYSIS CALCULATION 23 PAGES FOLLOW

Page 1 of 18 F0306-01 RO Strucfural integrity Associates, he.

CALCULATION PACmGIE File No.: PAL-13Q-301 Project No.: PAL-13Q PROJECT NAME:

Service Water Piping Flaw Evaluation and Flaw Growth Analysis CONTRACT NO.:

00001007 CLIENT:

Entergy Operation, Inc.

PLANT:

Palisades CALCULATION TITLE:

Flaw Evaluation Using ASME Code Case N-5 13-2 and Flaw Growth Analysis for Service Water Piping at Palisades Document Revision 0

Nuclear Plant Affected Pages 1 - 18 A1 -A5 Computer Files Revision Description Initial Issue Project Manager Approval Signature & Date

%&W&

R. 0. McGill 07/27/07 Preparer(s) &

Checker($)

Signatures & Date G. J. Licina 07/27/07

• e%%z&

R. 0. McGill 07/27/07 R. V. Perry 07/27/07

Structural lntegrify Associates. Inc.

Table of Contents

1.0 INTRODUCTION

...................................................................................................................... 3 2.0 METHODOLOGY....................................................................................................................... 3 3.0 ASSUMPTIONS / DESIGN INPUTS 4

4.0 CALCULATIONS AND RESULTS 4

5.0 CONCLUSION

S.......................................................................................................................... 6

6.0 REFERENCES

............................................................................................................................ 7 APPENDIX A SI PIPE EVAL INPUT AND OUTPUT.................................................................. A-1 List of Tables Table 1 : Calculated Allowable Flaw Sizes 5

List of Figures Figure 1. Planar Characterization of Through.wal1, Nonplanar Flaw 8

Figure 2 NDE Inspection Data of Effected Pipe Region from 10/27/06 9

Figure 3. NDE Inspection Data of Effected Pipe Region from 2/14/07 10 Figure 4 NDE Inspection Data of Effected Pipe Region from 5/09/07 11 Figure 5. NDE Inspection Data of Effected Pipe Region from 7/02/07 12 Figure 6. Circumferential Profile - Minimum Values 13 Figure 7. Circumferential Profile - Averages.....................................................................................

14 Figure 8. Axial Profiles.......................................................................................................................

15 Figure 9. Cumulative Distribution of Measured Thickness 16 Figure 10. Cumulative Distribution of Deltas (point-to-point thickness differences from one examination to the next)..........................................................................................................

17 Figure 1 1. Predicted UT Thickness Map, May 2009.......................................................................... 18 File No.. PAL-13Q-301 Page 2 of 18 Revision: 0

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1.0 INTRODUCTION

In July 2006, a pinhole leak was discovered approximately one foot downstream of control valve CV-0824 in the "Service Water Return from Containment" piping (HB-23-16) outside of the containment penetration MZ-13 [I]. This single pinhole is located on the bottom of the 16-inch carbon steel pipe in the 6 o'clock position [I]. The most recent NDE inspection data [2d] indicates that there are now 4 separate pinhole leaks in the same vicinity.

The initial leak was determined to be temporarily acceptable [3] per Code Case N-5 13-1 [4] at the time the leak was discovered (note the current 4 pinholes in combination would also be temporarily acceptable per the initial analysis); however, Palisades desires to implement repairs during the spring 2009 refueling outage which violates the provisions of the Code Case since repairs are not planned for the next scheduled outage (September 2007). The analysis contained herein is to provide technical justification for a planned relief request by the plant for postponing repair activity.

There are two objectives of the calculation. First, a flaw evaluation is performed to determine an allowable flaw size per Code Case N-5 13-2 [5], which provides specific guidance for through-wall nonplanar flaws. Second, a flaw growth analysis is performed based on NDE inspection data provided [2] to predict a bounding flaw size at the time of the spring 2009 outage. This flaw size is then compared to the allowable flaw size calculated.

2.0 METHODOLOGY The flaw evaluation is based on the criteria prescribed in ASME Code Case N-513-2. Use of this Code Case has been authorized by the Nuclear Regulatory Commission (NRC) for use by Palisades through relief request approval [6]. The Code Case allows for the evaluation of nonplanar, through-wall or part-wall flaws in Class 213 moderate energy piping. The through-wall, nonplanar flaw is to be evaluated as planar, through-wall flaws in the axial and circumferential directions (as described in Section 3.0(f) of the Code Case). This evaluation is performed using criteria in ASME Section XI [7]

as permitted by Code Case N-513-2.

The nonplanar, through-wall flaw evaluation herein was conducted using SI Pipe Eval software [8]

developed by Structural Integrity Associates. SI Pipe Eval is an Excel based evaluation tool programmed in Visual Basic for Applications that performs the flaw evaluation procedure described in Code Case N-5 13-2. SI Pipe Eval has been verified through the SI software QA program by an independent third party.

The flaw growth analysis is based on NDE inspection data of the affected pipe region provided by Palisades., Those inspection results were acquired on October 27,2006 [2a], February 14,2007 [2b],

May 9,2007 [2c] and July 2,2007 [2d]. More specifically, this inspected region is for the full circumference of the pipe for an axial distance of 9 inches downstream from the pipe-to-control valve weld on a one inch-by-one inch grid. Figures 2 through 5 depict the inspection data using File No.: PAL-13Q-301 Page 3 of 18 Revision: 0

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P contour plots. A trend and statistical analysis was performed to determine the flaw size at the time of the spring 2009 refueling outage, for comparison to the bounding flaw.

3.0 ASSUMPTIONS / DESIGN INPUTS The following assumptions are made for the analysis:

1. Service Level A safety factors are conservatively applied per Section 4.0 of Code Case N-5 13-2

[51.

2. For the flaw growth projection, the spring 2009 outage is assumed to begin on May 1,2009.

The following design inputs are used for the analysis (material properties are taken at the peak operating temperature):

1. PipeOD= 16inch[l].

2. Nominal wall thickness = 0.375 inch [I].

3. Maximum operating pressure = 50 psig [lo].

4. Maximum operating temperature = 200°F [I].

5. Material toughness (for circumferential flaws)" = 45 lblin [7, Table C-8321-11.

6. Material toughness (for axial flaws)" = 45 lblin [7, Table C-8322-11.

7. Dead weight stress = 1.0749 ksi [9].

8. OBE stress = 1.498 ksi [9].

9. DBE stress = 2.996 ksi [9].

10. Thermal expansion stress = 1.888 ltsi [9].

I I. Pipe material is A53 Grade A [I].

12. Allowable design stress, S = 12 ksi [l 1, Appendix 111, p.2691.

13. Code yield strength, S, = 30 ksi [12, p. 1051.

14. Code tensile strength, S, = 48 ksi [12, p. 1051.

15. Young's modulus, E = 28,600 ksi [1 1, Appendix I, p. 1291.

• Material toughness conservatively taken at lower shelf temperature.

4.0 CALCULATIONS AND RESULTS 4.1 Flaw Evaluation The planar flaw characterization approach is illustrated in Figure 1. Planar flaw evaluations are performed to determine allowable flaw sizes for comparison to the predicted flaw sizes (analysis below) using the assumptions and design input listed above. Table I summarizes the calculated allowable 'flaw sizes. SI Pipe Eva1 input and output are provided in Appendix A.

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I Axial I

36.52 I

Table 1: Calculated Allowable Flaw Sizes I

Circumferential I

25.58 I

Planar Direction 4.2 Flaw Growth Analysis Allowable Flaw Size (in)

Figures 2 through 5 show that thinning is confined to approximately half of the circumference with the most serious thinning at the edge of the weld. Those same thickness results are shown in 2-dimensional profile representations in Figures 6 through 8. In Figure 8, the axial profile shows there is a dramatic difference between the minimum reported value for a given circumferential position and the average for that circumferential band.

Figure 9 is a statistical plot that shows the cumulative distribution of the measured thickness at each of the four inspections. Figure 10 is also a cumulative distribution plot of the apparent deltas, where delta is determined by the point-to-point difference at each grid between successive inspections.

Note that negative delta values indicate that the thickness at that grid has increased.

Figure 9 shows that the cumulative distribution is basically bilinear. The best fit line at the higher thickness shows a very small variation in thickness that is near t,,,,

and that the measured thickness is greater than t,,,

for some measurements. The bilinear nature of Figure 9 demonstrates that there are actually two populations; one that is thinning (e.g., the lower half of the circumference), and one that is not. The lower thickness values, essentially all of which are at PHI values of -1 or less (PHI is essentially equivalent to the standard deviation of the observations). The differences between the best fit lines for different examinations provide an estimate of the rate of metal loss; at least since the first data set was collected in October 2006. The different data in Figure 9 show that not much thinning has occurred since February 2007. Best fit lines to the lower curves (i.e., where there is thinning) show that between October 2006 and July 2007 (248 days) that the rate of thinning is essentially 0.0273 inchlyear (7.48x10-~ inchlday).

Figure 10 shows the same basic data in a different way. Figure 10 shows the same effect observed from Figures 6 through 8, but more quantitatively, using the apparent deltas as the measure. The advantage of evaluating delta is that effects show up directly and changes can be observed more readily. The primary disadvantage is that the error in measurements (each thickness measurement will have an error associated with it; typically k0.010 inch for UT thickness measurements) will be magnified when the differences between subsequent individual measurements are compared. The means of all three data sets (i.e., the value at PHI = 0) are very close to zero, implying that the mean metal loss over the three measurements is very near zero. Figure 10 also shows that the vast majority of the metal loss occurred before the initial inspection in October 2006, with a much smaller amount of metal loss at any point between October 2006 and February 2007. Since February 2007, metal loss has been nil. he extremes of the apparent deltas were significant for the second -

data set, but have been much smaller in the two most recent inspections.

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Extrapolating these results to May 2009 indicates the minimum thickness in at least one grid will be 0 (i.e., a leak is definitely predicted) and the smallest average thickness of any circumferential band where thinning is occurring (actually half of a circumference) will be of the order of 0.150 inch.

Using the extreme values that the statistical plots permit predicts that the cumulative distribution of thickness in May 2009 will look like the plot in Figure 11. If it is assumed that all thinning occurs in the one inch grid closest to the weld, the band averages for that one inch grid will decrease from 0.292 inch (July 2007) to approximately 0.270 inch.

The UT thickness data have demonstrated that thinning was occurring prior to October 2006, that some thinning persisted between October 2006 and February 2007, but that essentially no thinning has occurred since that time. A key assumption in the projection to May 2009 is that the operative degradation mechanism that produced the thinning will be no more severe in the ensuing 22 months than it has been since October 2006. As such daily walkdowns and continued UT thickness determinations are recommended as discussed in Section 2.0(f) of the Code Case.

Note that calculation details are provided in the Excel file PAL-13Q Analysis.xls (included with the project files).

5.0 CONCLUSION

S A flaw evaluation based upon Code Case N-5 13-2 has shown that the current condition of the piping downstream of control valve CV-0824 in the Service Water Return from Containment piping (HB-23-16) outside of the containment penetration MZ-13 will maintain structural integrity, even in the presence of a pinhole leak. The acceptable t,i, (i.e., 360") for this piping is 0.033 inch [3]. An allowable flaw size per Code Case N-513-2 and the loading to which this line is subjected is 36.52 inches (axial) by 25.5 8 inches (circumferential).

Regular inspections of the pipe have shown that there was minimal flaw growth after the leak was first discovered, then characterized in October 2006. Since February 2007, flaw growth has been nil.

A projection of the flaw extent and depths based upon the entire history for which the pipe has been characterized using UT thickness measurements on one inch grids shows that at May 2009 the thinning will be larger than it is today; however, the predicted flaw will still be significantly smaller than the acceptable flaw size as calculated.

As noted above, the vast majority of the thinning occurred prior to October 2006, with some minimal thinning persisting between October 2006 and February 2007, but with essentially no thinning occurred since that time. A key assumption in the projection of these results to May 2009 is that the operative degradation mechanism that produced the thinning will be no more severe in the ensuing 22 months than it has been since October 2006. As such daily walkdowns and continued UT thickness determinations are recommended as discussed in Section 2.0(f) of the Code Case.

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6.0 REFERENCES

1. NMC, "Operability Recommendation," CAP: 01041995, Rev. 0, July 30,2006, SI File Number PAL-1 I 4-20 1.

2. Palisades NDE inspection data, SI File Number PAL-134-20 1 :

a. Ultrasonic Erosion Corrosion Examination Report, Work Order Number: 00294 169 06, Examination Date: 10/27/06.

b. Ultrasonic Erosion Corrosion Examination Report, Work Order Number: 002941 69 10, Examination Date: 2/14/07.

c. Ultrasonic Erosion Corrosion Examination Report, Work Order Number: 002941 69 13, Examination Date: 5/09/07.

d. Ultrasonic Erosion Corrosion Examination Report, Work Order Number: 002941 69 15, Examination Date: 7/02/07.

3. SI Calculation Package PAL-1 14-30 1, "Flaw Evaluation for Service Water Piping at Palisades Nuclear Plant Using ASME Code Case N-513-1," Revision 0.

4. ASME Code Case N-5 13-1, ccEvaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or Class 3 Piping Section XI, Division 1," Cases of ASME Boiler and Pressure Vessel Code, March 28,2001.

5. ASME Code Case N-513-2, "Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or Class 3 Piping Section XI, Division 1," Cases of ASME Boiler and Pressure Vessel Code, February 20,2004.

6. NRC Relief Request Approval Letter, "Safety Evaluation by the Office of Nuclear Regulation Use of ASME Code Case N-5 13-2," July 3,2006, SI File Number PAL-134-202.

7. ASME Boiler and Pressure Vessel Code,Section XI, Appendix C, 2001 Edition (2002 Addenda).

8. SI Pipe Eval, Version 1.3, Structural Integrity Associates, 2007.

9. Excerpt from Stress Report EA-SP-3316-01, Revision 5, provided as email attachment from George Schrader (Entergy) to Bob McGill (Structural Integrity), "PDF.pdf," Dated July 24, 2007, 5: 15 AM, SI File Number PAL-134-203.

10. Email from George Schrader (NMC) to Bob McGill (Structural Integrity), "FW: Service Water Piping Flaw Evaluation," Dated August 10,2006, 8:55 AM, SI File Number PAL-1 14-204.

1 1. ASME Boiler and Pressure Vessel Code, Section I11 Appendices, 1989 Edition.

12. ASME Boiler and Pressure Vessel Code, Section 11, Part A, 1989 Edition.

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Thraugh-wall penetration Section A-A I

Figure 1. Planar Characterization of Through-wall, Nonplanar Flaw File No.: PAL-13Q-301 Page 8 of 18 Revision: 0

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FLOW Figure 2. NDE Inspection Data of Effected Pipe Region from 10127106 File No.: PAL-13Q-301 Page 9 of 18 Revision: 0

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FLOW Figure 3. NDE Inspection Data of Effected Pipe Region from 2/14/07 File No.: PAL-13Q-301 Page 10 of 18 Revision: 0

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7 FLOW Figure 4. NDE Inspection Data of Effected Pipe Region from 5/09/07 File No.: PAL-13Q-301 Revision: 0 Page 11 of 18 F0306-01RO

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FLOW Figure 5. NDE Inspection Data of Effected Pipe Region from 7/02/07 File No.: PAL-13Q-301 Page 12 of 18 Revision: 0

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Minimum Thickness Values Figure 6. Circumferential Profile - Minimum Values 0.050 -

trninrn File No.: PAL-13Q-301 Revision: 0 Page 13 of 1 8 F0306-01RO 0.000 8

I 4

8 8

a 8

I pp p-0 @ $3 dZ +- $ p0

$ p3 $$

$ %F-

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so + Q+

%+

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Stru~tural Integrity Associates, Inc.

Average Thickness Values Figure 7. Circumferential Profile - Averages File No.: PAL-13Q-301 Page 14 of 18 Revision: 0

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Minimum & Average Thickness Values Axial Profile from Weld 0.000 -I I

1 2

3 4

5 6

7 8

9 Axial Position from Weld, inches (grids)

Figure 8. Axial Profiles File No.: PAL-13Q-301 Page 15 of 18 Revision: 0

Figure 9. Cumulative Distribution of Measured Thickness File No.: PAL-13Q-301 Page 16 of 18 Revision: 0

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Figure 10. Cumulative Distribution of Deltas (point-to-point thickness differences from one examination to the next)

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FLOW Figure 1 1. Predicted UT Thickness Map, May 2009 File No.: PAL-13Q-301 Revision: 0 Page 18 of 18 F0306-01 RO

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APPENDIX A SI Pipe Eva1 Input and Output File No.: PAL-13Q-301 Page A1 of A5 Revision: 0

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Table A-1: SI Pipe Eva1 Input Siruefoiai inf~griw Associates, lnc.

SI PIPE EVAL Best Vlewed with $024 x 768 Screen valuation Criteria for Temporary Acceptance of Flaws in Moderat OUTPUT Resolution P i ~ e

& Loadina Input Flaw Description Plpe OD =

I Ax~al Monplanar 2.l Material Pro~erties Austenitlc Ferritic P~pe Th~ckness =

Flaw Length Pipe Pressure =

Flaw to Thickness Ratio (alt)

Allowable Design Stress. S =

ksi Through-wall Flaws (all = I)

Operating Temperature =

Code Yield Strength, S, =

ksi Resuilant DW Mament =

Resullant Seismic OBE Moment =

Resultant Selsmrc DBE Moment =

bs Resultant Thermal Moment =

-Ibs Allowable Flaw: 136.52lin Select Sewlce Level vcrsion 1.3 Execution Dale:

7127,2007 Code Case Evaluation:

Code Tensile Strength, S, =

ksi Young's Modulus =

ksi NOTE: Results must be cleared proor Raslilts to new run I Notes:

1. Moments are derived from, M = 61, where 1 = moment of inertia and R = outside pipe radius.

R See Excel file Moment from Stress.xls (included in project files) for calculation details.

2. Flaw length is arbitrarily chosen.

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Table A-2: §I Pipe Eva1 Axial Evaluation Output SI PIPE EVAL, SOLUTION

SUMMARY

Axial Nonplanar, Ferritic (Note: flaw is treated as an axial and circumferential planar flaw. Flaw must pass bath conditions.)

Description of Solution Methodolooy:

A screening criteria [ASME Section Xi Appendix C (2001). Section C-43001 must first be performed to determine the fracture analysis method. If the screening criteria calls for an EPFM or Limit Load analysis, then the inputs provided are used with the hoop stress and material flow stress calculated from Equations 2 and 3 of Code Case N-513-2 for use in Equation 1 to determine the allowable flaw length. If the screen criteria caiis for an LEFM analysis, then the inputs provided are used with the evaluations procedures described in Section C-7200. An iterative process is used to determine the allowable flaw length.

SCREEN CRITERIA DETERMINATION S C < 0. 2 0. 2 s S C < 1. 8 S C r l. 8 Screening Criteria =

1.73 SC = K; / S;Section XI Appendix C, Figure C-4220-1 Limit Load EPFM LEFM K; =

0.067 K; = [I 000K: I E 'JI,]0'5 SectionXl Appendix C. Section C-4310 S; =

0.035 S; = (pi?, 1 t) la, Section Xi Appendix C. Section C-4310 (Note: sigma y used instead of sigma I for through-wall flaw.)

Variables Used i n Above Equations:

K, =

2,502 p ~ i - i n l ' ~ K, = (pi?, I t)(xa IQ)'

F Section XI Appendix C. Section C-4312 D - t R,

= 7.8425 in R,

=

Q =

7.09 Q = 1 + 4.593 (a 1 1 ) ~ ' ~ ~

Section XI Appendix C. Section C-4312 2

F =

2.31 F = 1.12+0.053a +0.0055u2 + (1.0+ 0.02u+ 0.0191aZ)(20 -R, 1t)~/1400 Section XI Appendix C, Section C-4312 Ci =

si Section XI Appendix C. Figure C-4220-1 E ' = 3.4E+07 psi E = E 1 (I - u2 )

Section XI Appendix C, Section C-1300 J,, =

45 in-lb/in2 LIMIT LOAD 8 EPFM ANALYSIS THIS ANA YSlS IS USED Flow Stress =

39,000 psi a, = (S + s")/ 2 Code Case N-513-2 Equation 3 Hoop Stress =

i.067 psi 0, = pDo 1 2t Code Case N-513-2 Equation 2 Structural Factor. Membrane =

2.7 Section XI Appendix C. Section C-2622 2

Code Case N-513-2 Equation 1 A o w b i e F a

n t

h

=

3652 in a, l = 1, 5 s f i [ ( ~ ) l

-,]

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Table A-3: SP Pipe Eval Circumferential Evaluation Output SI PIPE EVAL, SOLUTION

SUMMARY

Circumferential Nonplanar, Ferritic (Note: flaw is treated as an axial and circumferential planar flaw. Flaw must pass both conditions.)

Description of Solution Methodoloqy:

A screening criteria [ASME Section XI Appendix C (2001), Section C-43001 must first be periormed to determine the fracture analysis method. If the screening criteria calls for a Limit Load analysis, then inputs provided are used with ASME Section XI Appendix C (2001), Section C-5320. An iterative approach is used on theta (half crack angle) to determine the allowable flaw size conforming to the allowable pipe bending stress and allowable pipe membrane stress. If the screening criteria calls for an EPFM analysis, then the inputs provided are used with Section C-6320. The analysis is identical to the Limit Load analysis except that a Z adjustment factor is used in determining the allowable pipe bending and membrane stresses. If the screen criteria calls for an LEFM analysis, then the inputs provided are used with the evaluations procedures described in Section C-7200. An iterative process is used to determine the allowable flaw length.

D o - t 20.83 The ratio of mean radius to thickness is greater than 20. thus the analysis will be conservative.

t R,

=

7.81 in R, = -

2 SCREEN CRITERIA DETERMINATION SC < 0.2 0.2 < SC < 1.8 SC t I

.8 Screening Criteria =

1.85 SC = K; I S;

Section XI Appendix C. Figure C-4220-1 LimitLoad EPFM LEFM K; =

o.280 K) = [I 0 0 0 ~ : 1 E ' J ~, ] ~ ' ~ Section XI Appendix C. Section C-4310 s; =

0.151 Sf = (Gb + Oe)/ 0; when (0, + G,) > a, else Sf = G, 10,Section XI Appendix C, Section C-4310 Variables Used i n Above Equations:

KI =

37.488 psi-in" I<, = Kl, + Klb Section XI Appendix C, Section C-4311 KI, =

7.789 psi-in1' Kim = [P I(~KR,~)] ( ~ a ) " ~

F,Section XI Appendix C. Section C-4311, where:

P =

9,133 Ibs Klb =

29,699 psi-in" Klb = [M ( K R ~

t)] (Ka )0'5 Fb Section XI Appendix C. Section C-4311, where:

M = 317,425 in-lbs Fm =

4.98 F,

= 1. I 0 + x 0 15241+ 1 6. 7 7 2 ( ~ 0 / ~ ) ~ ~ ~ ~

- 1 4, g 4 4 ( x ~ / ~ ) ]

Section XIAppendix C. Section C-4312

[.

Fb =

3.48 Fb = 1. I 0 + x[-0.09967 + 5.0057 (x0 / x)' 565 - 2.8329 (x0 /x)]

Section XI Appendix C, Section C-4312 E' = 3.1~+07 psi E = E 1 (I - u2)

Section XI Appendix C. Section C-1300 Jlc =

45 in-lblin2 ob =

2.573 psi cfe =

1,945 psi G, =

533 psi a, = D,M, 121 a, = D,M, I21

= p ~,

14t Section XI Appendix C. Section C-2500 cfb =

29.878 psi a -

2a'[2sinp--r~nB where when (B+P)sn t

I I

Section XI Aooendix C. Section C-4311 DL =?[(2-:)SinP]

where p = n [ 1---^n)l[2-+)

43.4 when

( B + p ) > n (T =

si Section XI Appendix C. Figure C-4220.1 (T,

=

1 Section XI Appendix C. Section C-4311 File No.: PAL-13Q-301 Revision: 0 Page A4 of A5

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Table A-3: SI Pipe Eval Circumferential Evaluation Output (cont.)

SI PIPE EVAL, SOLUTION

SUMMARY

Circumferential Nonplanar, Ferritic (continued)

LEFM ANALYSIS Structural Factor, Membrane =

2.7 Structural Factor, Bending =

2.3 Section XI Appendix C, Section C-2621 CT =

2,573 psi ce =

1,945 psi c, =

533 psi o, = D,Mb 121 o, = D,M, 121

= p

~

o 14t Section XI Appendix C, Section C-2500 F,

=

4.98 F,

= 1 + A, (8 ~ x ) " ~

+ 9, (8 171)~'~

+ C, (8 Code Case N-513-2 Appendix 1-2.0 where:

A,

= -2.02917+1.67763(Rm /t)-0.07987(Rm/t)2 +0.00176(~,lt)3 B, =7.09987-4.42394(~,lt)+0.21036(~,/t~ -0.00463(Rm/t)3 C,

=7.79661+5.16676(Rm/t)-0.24577(~, ~ t ) ~

+0.00541(Rm/t)3 Fb=

3.48 F b = 1 + ~ b ( 8 1 x ) 1 ' 5 + ~ b ( 8 / x ) 2 ~ 5 + ~ b ( 8 / x ) 3 ' 5 Code Case N-513-2 Appendix 1-2.0 where:

A, = -3.26543+1.52784(~,/t)-0.072698(~~lt~ +0,0016011(~,/t~

B, =11.36322-3.91412(~,/t)+0.18619(~~lt~-0.004099(~~/t)~

C, = -3.18609+3.84763(Rm It)-0.18304(Rm /t)' +0.00403(~,lt)3 KI, =

7,789 Kim = (SFm)Fmom

( 7 ~ a ) " ~

Section XI Appendix C, Section C-7300 K, b =

29,699 K l b = [ ( ~ ~ b ) o b + o e ] ~ b ( x a ) 0 ' 5 Section XI Appendix C, Section C-7300 K ~ r

=

K, from residual stresses at the flaw location,Section XI Appendix C, Section C-7300 KI =

37,488 psi-in"'

KI = Kim + Klb + Klr Section XI Appendix C, Section C-7300 Kc =

37,607 psi-in1

Kc = (JI,E '1 1 0 0 0 ) ~ ' ~ Section XI Appendix C, Section C-7200 Allowable Flaw Length =

25.58 in Entered Flaw Length =

4.0 in The half flaw length is incrementally increased up to the stability condition limit:

KI I Kc File No.: PAL-13Q-301 Page A5 of A5 Revision: 0