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{{#Wiki_filter:ATTACHMENT 4 TO ENTERGY LETTER 2.14.023 PILGRIM RELIEF REQUEST PRR-25 Calculation Cover Page EC # 49514 Flaw Evaluation of SSW Discharge Piping Leaking Elbow Structural Integrity Associates Calculation No. 1400287.302, Rev. 0 (20 Pages) | {{#Wiki_filter:ATTACHMENT 4 TO ENTERGY LETTER 2.14.023 PILGRIM RELIEF REQUEST PRR-25 Calculation Cover Page EC # 49514 Flaw Evaluation of SSW Discharge Piping Leaking Elbow Structural Integrity Associates Calculation No. 1400287.302, Rev. 0 (20 Pages) | ||
ATTACHMENT 9.2 ENGINEERING CALCULATION COVER PAGE Sheet 1 of 2[] ANO-1 13 ANO-2 El GGNS [1 IP-2 [I IP-3 [E PLP f- JAF Z PNPS [1 RBS El VY [I W3 El NP-GGNS-3 | |||
[I NP-RBS-3 CALCULATION | ATTACHMENT 9.2 ENGINEERING CALCULATION COVER PAGE Sheet 1 of 2 | ||
()EC # 49514 (2) Page 1 of 20)COVER PAGE (3) Design Basis Calc. E-- YES NO (4) [Z CALCULATION Markup 15) Calculation No: M1398 (5) Revision: | [] ANO-1 13 ANO-2 El GGNS [1 IP-2 [I IP-3 [E PLP f- JAF Z PNPS [1 RBS El VY [I W3 El NP-GGNS-3 [I NP-RBS-3 CALCULATION ()EC # 49514 (2)Page 1 of 20) | ||
0 (7) Title: Flaw Evaluation of SSW Discharge Piping Leaking Elbow ,1) Editorial DYES Z NO (9) System(s): | COVER PAGE (3) Design Basis Calc. E--YES Z* NO (4) [Z CALCULATION [-*EC Markup | ||
29 (10) Review Org (Department): (ii) Safety Class: (12) Component/Equipment/Structure Type/Number: | : 15) Calculation No: M1398 (5) Revision: 0 (7) | ||
Z Safety / Quality Related PIPE / JF29-8-4[] Augmented Quality Program i-- Non-Safety Related (13) Document Type: CALC (14) Keywords (Description/Topical Codes): JF29-8-4, spool, SIA, Structural Integrity Associates, flaw, leak, rubber lining, 1400287.302, 1400287 | |||
0 I. EC Markups Incorporated (N/A to NP calculations) 1.N/A 2.3.4.5.11. Relationships: | ==Title:== | ||
Sht Rev Input Output Impact Tracking Doc Doc Y/N No.1. Specification M300 2-12 109 x 0 N 2. M100-7250 | Flaw Evaluation of SSW Discharge Piping Leaking Elbow ,1) Editorial DYES Z NO (9) System(s): 29 (10) Review Org (Department): | ||
-5 x 0 N 3. __ 0 0 4. _ _0 0 5. 0 0 | (ii) Safety Class: (12) Component/Equipment/Structure Type/Number: | ||
Z Safety / Quality Related PIPE / JF29-8-4 | |||
[] Augmented Quality Program i-- Non-Safety Related (13) Document Type: CALC (14) Keywords (Description/Topical Codes): | |||
-f JF29-8-4, spool, SIA, Structural Integrity Associates, flaw, leak, rubber lining, 1400287.302, 1400287 REVIEWS (15) Name/Signature/Date (16) Name/Signature/Date (17) Name/Signature/Date Structural Integrity Assoc. John A. Tucker 3. Iq See IAS Responsible Engineer -- Design Verifier Supervisor/Approval Z Reviewer Ei- Comments Attached E- Comments Attached EN-DC-126 R005 | |||
ATAHMENT19of3 CALCULATION REFERENCE SHEET Sheet 1 of 3 CALCULATION CALCULATION NO: M1398 REFERENCE SHEET REVISION: 0 I. EC Markups Incorporated (N/A to NP calculations) 1.N/A 2. | |||
3. | |||
4. | |||
5. | |||
: 11. Relationships: Sht Rev Input Output Impact Tracking Doc Doc Y/N No. | |||
: 1. Specification M300 2-12 109 x 0 N | |||
: 2. M100-7250 - 5 x 0 N | |||
: 3. __ 0 0 | |||
: 4. _ _0 0 | |||
: 5. 0 0 __ | |||
III. CROSS | |||
==REFERENCES:== | ==REFERENCES:== | ||
: 1. ASME B&PV Code, Section XI, App C, 2001 Edition w/ Add through 2003 2. ASME B31.1, Power Piping, 1967 Edition 3. ASME Code Case N-513-3 4. Flow of Fluids Through valves, Fittings and Pipe, Crane Co,., Technical Paper No.410 IV. SOFTWARE USED: Title: N/A Version/Release: | : 1. ASME B&PV Code, Section XI, App C, 2001 Edition w/ Add through 2003 | ||
-- DisklCD No. --V. DISK/CDS INCLUDED: Title: N/A Version/Release Disk/CD No.VI. OTHER CHANGES: EN-DC-126 R005 | : 2. ASME B31.1, Power Piping, 1967 Edition | ||
: 3. ASME Code Case N-513-3 | |||
Signature | : 4. Flow of Fluids Through valves, Fittings and Pipe, Crane Co,., Technical Paper No. | ||
& Date Signatures | 410 IV. SOFTWARE USED: | ||
& Date 0 1 -15 Initial Issue A-i -A-3 Eric Houston Brad Dawson EJH 3/3/14 BPD 3/3/14 Raoul Gnagne LRG 3/3/14 Robert McGill ROM 3/3/14 Page 1 of 15 F0306-01 R1 j | |||
3 2.0 TECHNICAL APPROACH ..................................................................................... | ==Title:== | ||
3 3.0 DESIGN INPUTS / ASSUMPTIONS | N/A Version/Release: -- DisklCD No. -- | ||
...................................................................... | V. DISK/CDS INCLUDED: | ||
4 4.0 | |||
5 4.1 | ==Title:== | ||
5 4.1.1 | N/A Version/Release Disk/CD No. | ||
5 4.1.2 A xial Stresses ................................................................................................ | VI. OTHER CHANGES: | ||
6 4.2 Stress Intensity Factor Calculations | EN-DC-126 R005 | ||
............................................................. | |||
7 4.3 Critical Fracture Toughness Determination | StructuralIntegrity Associates, Inc File No.: 1400287.302 Project No.: 1400287 CALCULATION PACKAGE Quality Program: Z Nuclear E] Commercial PROJECT NAME: | ||
.................................................. | Pilgrim Leaking Elbow Evaluation Support CONTRACT NO.: | ||
8 5.0 R E SU | 10404807, Change Order No. 001 CLIENT: PLANT: | ||
8 6.0 C O | Entergy Nuclear Pilgrim Nuclear Power Station CALCULATION TITLE: | ||
8 7.0 R E FERE N | Flaw Evaluation of SSW Discharge Piping Leaking Elbow Document Affected Project Manager Preparer(s) & | ||
10 APPENDIX A DRAFT CODE CASE N-513-4 PROCEDURES FOR ELBOW FLAW | Revision Pages Revision Description Approval Checker(s) | ||
A -1 List of Tables Table 1: Jic Values for A106 Gr. B Carbon Steel from NRC's Pipe Fracture Database [10] 11 Table 2: Axial and Circumferential Structural Factors [4] ................................................ | Signature & Date Signatures & Date 0 1 - 15 Initial Issue A-i - A-3 Eric Houston Brad Dawson EJH 3/3/14 BPD 3/3/14 Raoul Gnagne LRG 3/3/14 Robert McGill ROM 3/3/14 Page 1 of 15 F0306-01 R1 | ||
12 Table 3: Load Combinations for Circumferential Flaw Analyses ..................................... | |||
12 Table 4: Allowable Through-Wall Flaw Lengths (based on t = 0.312") ............................ | j StructuralIntegrity Associates, Inc0 Table of Contents 1.0 INTRO DU CTION .................................................................................................... 3 2.0 TECHNICAL APPROACH ..................................................................................... 3 3.0 DESIGN INPUTS / ASSUMPTIONS ...................................................................... 4 4.0 CA LCULA TIO N S ..................................................................................................... 5 4.1 Applied Loads .............................................................................................. 5 4.1.1 Ho op S tress........................................................................................................ 5 4.1.2 A xial Stresses................................................................................................ 6 4.2 Stress Intensity Factor Calculations ............................................................. 7 4.3 Critical Fracture Toughness Determination .................................................. 8 5.0 R E SU LT S ...................................................................................................................... 8 6.0 C O NC LU SIO NS ...................................................................................................... 8 7.0 R E FERE N CE S ...................................................................................................... 10 APPENDIX A DRAFT CODE CASE N-513-4 PROCEDURES FOR ELBOW FLAW EVA LU A TIO N ....................................................................................... A -1 List of Tables Table 1: Jic Values for A106 Gr. B Carbon Steel from NRC's Pipe Fracture Database [10] 11 Table 2: Axial and Circumferential Structural Factors [4] ................................................ 12 Table 3: Load Combinations for Circumferential Flaw Analyses ..................................... 12 Table 4: Allowable Through-Wall Flaw Lengths (based on t = 0.312") ............................ 12 List of Figures Figure 1. Pinhole Leak in Service Water Piping, 18-inch Elbow ....................................... 13 Figure 2. Sketch of Leak Location in Service Water Piping, 18-inch Elbow ................... 14 Figure 3. UT Data (3/4 Inch Grid) for Service Water Piping, 18-inch Elbow ................... 15 File No.: 1400287.302 Page 2 of 15 Revision: 0 F0306-OIRI | ||
12 List of Figures Figure 1. Pinhole Leak in Service Water Piping, 18-inch Elbow ....................................... | |||
13 Figure 2. Sketch of Leak Location in Service Water Piping, 18-inch Elbow ................... | jStructural Integrity Associates, IncY | ||
14 Figure 3. UT Data (3/4 Inch Grid) for Service Water Piping, 18-inch Elbow ................... | |||
15 File No.: 1400287.302 Page 2 of 15 Revision: | |||
0 F0306-OIRI jStructural Integrity Associates, IncY | |||
==1.0 INTRODUCTION== | ==1.0 INTRODUCTION== | ||
A weeping flaw, shown on Figure 1, was discovered near the extrados of a 90 degree elbow in the Salt Service Water (SSW) piping at Pilgrim Nuclear Power Station (Pilgrim). | A weeping flaw, shown on Figure 1, was discovered near the extrados of a 90 degree elbow in the Salt Service Water (SSW) piping at Pilgrim Nuclear Power Station (Pilgrim). The leak is located on the JF29-8-4 pipe spool of the SSW system [1]. Ultrasonic testing has been conducted in order to characterize the flaw [1]. Allowable through-wall flaw lengths are determined using methods consistent with an upcoming revision of Code Case N-513-3 [2] as described below. | ||
The leak is located on the JF29-8-4 pipe spool of the SSW system [1]. Ultrasonic testing has been conducted in order to characterize the flaw [1]. Allowable through-wall flaw lengths are determined using methods consistent with an upcoming revision of Code Case N-513-3 [2] as described below.2.0 TECHNICAL APPROACH The flaw evaluation herein is based on the criteria prescribed in an upcoming revision of ASME Code Case N-513-3. This Code Case allows for the temporary acceptance of through-wall flaws in moderate energy Class 2 or Class 3 piping. N-513-3 has been conditionally accepted by the NRC with the stipulation that, "The repair or replacement activity temporarily deferred under the provisions of this Code Case shall be performed during the next scheduled outage," and is published in the latest revision of Regulatory Guide 1.147 [3]. N-513-3 allows non-planar, through-wall flaws to be characterized and evaluated as planar (i.e., crack-like), through-wall flaws in the axial and circumferential directions. | 2.0 TECHNICAL APPROACH The flaw evaluation herein is based on the criteria prescribed in an upcoming revision of ASME Code Case N-513-3. This Code Case allows for the temporary acceptance of through-wall flaws in moderate energy Class 2 or Class 3 piping. N-513-3 has been conditionally accepted by the NRC with the stipulation that, "The repair or replacement activity temporarily deferred under the provisions of this Code Case shall be performed during the next scheduled outage," and is published in the latest revision of Regulatory Guide 1.147 [3]. N-513-3 allows non-planar, through-wall flaws to be characterized and evaluated as planar (i.e., crack-like), through-wall flaws in the axial and circumferential directions. | ||
The evaluation criteria provided in N-513-3 are only for straight pipe since the technical approach relies on ASME Section XI, Appendix C [4] methods. A new revision of the Code Case (N-513-4) includes rules for the evaluation of piping components such as elbows, branch tees and reducers. | The evaluation criteria provided in N-513-3 are only for straight pipe since the technical approach relies on ASME Section XI, Appendix C [4] methods. A new revision of the Code Case (N-513-4) includes rules for the evaluation of piping components such as elbows, branch tees and reducers. Flaws in these components may be evaluated as if in straight pipe provided the stresses used in the evaluation are adjusted to account for geometric differences. For elbows, hoop stress is adjusted by considering flaw location and primary stress due to elbow ovalization from axial loads. For axial stresses, the stress scaling follows the same approach given in ASME Section III, ND-3600 [5] design by rule using stress indices and stress intensification factors for the adjustment. Details are provided in N-513-4 for determining these adjusted stresses. | ||
Flaws in these components may be evaluated as if in straight pipe provided the stresses used in the evaluation are adjusted to account for geometric differences. | N-513-4 has not been approved by the ASME or reviewed by the NRC; however, it is recognized in ASME committee that the technical approach is very conservative. Simple treatment of piping component flaw evaluation using hand calculations was an important objective in the development of the approach recognizing the trade-off being conservative results. N-513-4 allows for more sophisticated analysis by the user. | ||
For elbows, hoop stress is adjusted by considering flaw location and primary stress due to elbow ovalization from axial loads. For axial stresses, the stress scaling follows the same approach given in ASME Section III, ND-3600 [5] design by rule using stress indices and stress intensification factors for the adjustment. | As stated above, Code Case N-513-3 evaluation criteria rely on the methods given in ASME Section XI, Appendix C. Linear Elastic Fracture Mechanics (LEFM) criteria are conservatively employed as described in Article C-7000. Since a through-wall flaw is being evaluated, through-wall shape factors Fm, Fb and F are used which are given in Appendix I of the Code Case. Allowable flaw lengths are determined through iteration comparing calculated stress intensity factors to a critical fracture toughness defined in C-7200 of Section XI, Appendix C. | ||
Details are provided in N-513-4 for determining these adjusted stresses.N-513-4 has not been approved by the ASME or reviewed by the NRC; however, it is recognized in ASME committee that the technical approach is very conservative. | This evaluation utilizes finite element methods (FEM) to calculate the primary membrane stress in the hoop direction due to ovalization from axial loads. Section 3.3 of the Code Case's new revision states File No.: 1400287.302 Page 3 of 15 Revision: 0 F0306-01RI | ||
Simple treatment of piping component flaw evaluation using hand calculations was an important objective in the development of the approach recognizing the trade-off being conservative results. N-513-4 allows for more sophisticated analysis by the user.As stated above, Code Case N-513-3 evaluation criteria rely on the methods given in ASME Section XI, Appendix C. Linear Elastic Fracture Mechanics (LEFM) criteria are conservatively employed as described in Article C-7000. Since a through-wall flaw is being evaluated, through-wall shape factors Fm, Fb and F are used which are given in Appendix I of the Code Case. Allowable flaw lengths are determined through iteration comparing calculated stress intensity factors to a critical fracture toughness defined in C-7200 of Section XI, Appendix C.This evaluation utilizes finite element methods (FEM) to calculate the primary membrane stress in the hoop direction due to ovalization from axial loads. Section 3.3 of the Code Case's new revision states File No.: 1400287.302 Page 3 of 15 Revision: | |||
0 F0306-01RI jstructural Integrity Associates, IncO that "Alternative methods may be used to calculate the stresses used in evaluation," which justifies the use of FEM techniques. | jstructural Integrity Associates, IncO that "Alternative methods may be used to calculate the stresses used in evaluation," which justifies the use of FEM techniques. | ||
Details of the Code Case N-513-4 evaluation procedure for elbows are given in Appendix A.3.0 DESIGN INPUTS / ASSUMPTIONS The SSW Code of Construction is ANSI B31.1 1967 Edition [6].Based on information provided by Entergy, the 18 inch elbow is located on SSW spool JF29-8-4 [1].The 90 degree elbow located on JF29-8-4 is a schedule 20, long radius elbow [7]. The design pressure and temperature are 10 psig and 100°F, respectively | Details of the Code Case N-513-4 evaluation procedure for elbows are given in Appendix A. | ||
[8].The elbow material is ASTM A-234 WPB [7] carbon steel. For the analysis, A106 Gr. B carbon steel is judged to have equivalent material properties. | 3.0 DESIGN INPUTS / ASSUMPTIONS The SSW Code of Construction is ANSI B31.1 1967 Edition [6]. | ||
The nominal composition of the two materials is essentially the same and the minimum yield and tensile strengths are the same for both materials. | Based on information provided by Entergy, the 18 inch elbow is located on SSW spool JF29-8-4 [1]. | ||
In addition, the longitudinal and transverse elongations are similar between these materials. | The 90 degree elbow located on JF29-8-4 is a schedule 20, long radius elbow [7]. The design pressure and temperature are 10 psig and 100°F, respectively [8]. | ||
The applied moment loadings are obtained from the ME-101 output listings in Reference | The elbow material is ASTM A-234 WPB [7] carbon steel. For the analysis, A106 Gr. B carbon steel is judged to have equivalent material properties. The nominal composition of the two materials is essentially the same and the minimum yield and tensile strengths are the same for both materials. In addition, the longitudinal and transverse elongations are similar between these materials. | ||
[9]. Based on information provided by Entergy, the location of interest is node 22. The moments for each load case are provided in three dimensions (MA, MB, and MC), which are combined by square-root-of-the-sum-of-the-squares (SRSS). The resulting SRSS moments at each location along the elbow (beginning, middle, and end) are compared for each loading, and the bounding moment is used in this analysis.Determination of the fracture toughness, Jic, used in the evaluation is based on Section XI, Appendix C, C-8320 [4], which specifies that 'reasonable lower bound fracture toughness data' may be used to determine the allowable stress intensity factor, Kic. The NRC's Pipe Fracture Encyclopedia | The applied moment loadings are obtained from the ME-101 output listings in Reference [9]. Based on information provided by Entergy, the location of interest is node 22. The moments for each load case are provided in three dimensions (MA, MB, and MC), which are combined by square-root-of-the-sum-of-the-squares (SRSS). The resulting SRSS moments at each location along the elbow (beginning, middle, and end) are compared for each loading, and the bounding moment is used in this analysis. | ||
[10]contains numerous CVN test results for A106 Gr. B carbon steel at low temperature, which are reproduced in Table 1. The minimum reported value of 293 in-lb/in 2 is used in the analysis for both axial and circumferential flaws.Finite element methods are used to determine the primary membrane stress in the hoop direction due to ovalization from axial loads in Reference | Determination of the fracture toughness, Jic, used in the evaluation is based on Section XI, Appendix C, C-8320 [4], which specifies that 'reasonable lower bound fracture toughness data' may be used to determine the allowable stress intensity factor, Kic. The NRC's Pipe Fracture Encyclopedia [10] | ||
[11]. A unit moment of 10,000 in-lbs is applied to the FEM and linearized stresses are extracted at paths in the axial direction from the flaw. A stress of 100 psi conservatively bounds the tensile hoop stress reported in Reference | contains numerous CVN test results for A106 Gr. B carbon steel at low temperature, which are reproduced in Table 1. The minimum reported value of 293 in-lb/in 2 is used in the analysis for both axial and circumferential flaws. | ||
[11]. This bounding stress is factored based on the ratio of the applied moment for the applicable service level to the unit moment of 10,000 in-lbs. The factored stress is used as described in Section 4.1.1 below.The following design inputs are used in this calculation: | Finite element methods are used to determine the primary membrane stress in the hoop direction due to ovalization from axial loads in Reference [11]. A unit moment of 10,000 in-lbs is applied to the FEM and linearized stresses are extracted at paths in the axial direction from the flaw. A stress of 100 psi conservatively bounds the tensile hoop stress reported in Reference [11]. This bounding stress is factored based on the ratio of the applied moment for the applicable service level to the unit moment of 10,000 in-lbs. The factored stress is used as described in Section 4.1.1 below. | ||
: 1. Long radius 900 elbow OD = 18 inches [7]2. Nominal elbow thickness | The following design inputs are used in this calculation: | ||
= 0.312 inch (based on Schedule 20 piping [7])3. Design pressure = 10 psig [8]File No.: 1400287.302 Page 4 of 15 Revision: | : 1. Long radius 900 elbow OD = 18 inches [7] | ||
0 F0306-01 RI jstructural Integrity Associates, Inc!4. Design temperature | : 2. Nominal elbow thickness = 0.312 inch (based on Schedule 20 piping [7]) | ||
= 100'F [8]5. Young's modulus = 27,900 ksi [6, Table C-I]6. Allowable stress = 15 ksi [6, Table A-2]7. Enveloped SRSS Deadweight Moment = 43,973 in-lbs [9]8. Enveloped SRSS OBE Moment = 38,820 in-lbs [9]9. Enveloped SRSS SSE Moment = 72,789 in-lbs [9]10. Enveloped SRSS Thermal Moment = 22,047 in-lbs [9]11. Stress intensification factor, i = 3.98 [6]12. Jhc for axial flaws = 293 in-lb/ | : 3. Design pressure = 10 psig [8] | ||
[I].Therefore, the use of the 0.312 inch surrounding wall thickness is considered conservative. | File No.: 1400287.302 Page 4 of 15 Revision: 0 F0306-01 RI | ||
jstructural Integrity Associates, Inc! | |||
: 4. Design temperature = 100'F [8] | |||
: 5. Young's modulus = 27,900 ksi [6, Table C-I] | |||
: 6. Allowable stress = 15 ksi [6, Table A-2] | |||
: 7. Enveloped SRSS Deadweight Moment = 43,973 in-lbs [9] | |||
: 8. Enveloped SRSS OBE Moment = 38,820 in-lbs [9] | |||
: 9. Enveloped SRSS SSE Moment = 72,789 in-lbs [9] | |||
: 10. Enveloped SRSS Thermal Moment = 22,047 in-lbs [9] | |||
: 11. Stress intensification factor, i = 3.98 [6] | |||
: 12. Jhc for axial flaws = 293 in-lb/in2 [4, 10] | |||
: 13. Jic for circumferential flaws = 293 in-lb/in 2 [4, 10] | |||
: 14. Bounding primary membrane stress in the hoop direction due to unit moment load = 100 psi [11] | |||
Note that the wall thickness surrounding the flaw is greater than the elbow nominal thickness [I]. | |||
Therefore, the use of the 0.312 inch surrounding wall thickness is considered conservative. | |||
The following assumptions are used in this calculation: | The following assumptions are used in this calculation: | ||
: 1. Poisson's ratio is assumed to be 0.3.2. Due to the flaw remoteness from a weld, residual stress effects are assumed negligible. | : 1. Poisson's ratio is assumed to be 0.3. | ||
: 3. A corrosion allowance is not considered (the ongoing inspection requirements in Code Case N-513-3 address the possibility of flaw growth during the temporary acceptance period).4.0 CALCULATIONS 4.1 Applied Loads 4.1.1 Hoop Stress For the allowable axial flaw length, the hoop stress, Gh, due to internal pressure and elbow ovalization from the axial moments may be determined from Equation 9 of N-513-4 (see Appendix A):=( p 0 | : 2. Due to the flaw remoteness from a weld, residual stress effects are assumed negligible. | ||
0 F0306-01 R1 | : 3. A corrosion allowance is not considered (the ongoing inspection requirements in Code Case N-513-3 address the possibility of flaw growth during the temporary acceptance period). | ||
= t*Rbend/(R mean)2 [6]Rmean = elbow mean radius, in Mb = primary bending moment, in-lbs I = moment of inertia, in4.Note that the first term of Equation I accounts for the hoop stress due to internal pressure and includes a scaling factor to account for the circumferential location of the flaw (assuming uniform thickness, pressure based hoop stress is a maximum at the elbow intrados, while a minimum at the elbow extrados). | 4.0 CALCULATIONS 4.1 Applied Loads 4.1.1 Hoop Stress For the allowable axial flaw length, the hoop stress, Gh, due to internal pressure and elbow ovalization from the axial moments may be determined from Equation 9 of N-513-4 (see Appendix A): | ||
At the flank, the pressure based hoop stress is equal to that of straight pipe. For the analysis herein, it is conservative to set 0 = 0 since the flaw is between the flank and extrados as shown on Figure 2.The second term of Equation 1 accounts for the hoop stress resulting from the axial moments acting to ovalize the elbow. This term is replaced with the scaled primary membrane stress in the hoop direction as discussed in the previous section.Finally, N-513-4 limits the use of Equation 1 for h> 0.1. For this elbow, h z 0.11.4.1.2 Axial Stresses For the allowable circumferential flaw length, the axial stress due to pressure, deadweight, seismic, and thermal loading is presented below. For axial membrane stress due to pressure, am, Equation 10 of N-513-4 is used: B,2tD (2)where Bi is an ASME Section III primary stress index for internal pressure. | =( p 0 2Rbend + R.Sin6 1 ( 1.95 )~RMb (1) | ||
N-513-4 sets this value to 0.5.For axial bending stress, ab, due to deadweight and seismic moments, Equation 11 ofN-513-4 may be used: o-b = B2 (-R --b (3)where B2 is an ASME Section III primary stress index for moment loading. From Figure ND-3673.2(b)-I of Reference | =(Pt L2(Rb,,d + Ro sin 0) h 92/3 )1 where: | ||
[5], B2 = 1.30/h 2/3.For this elbow, B2 = 5.74.For axial bending stress due to thermal moments, (e, Equation 12 of N-513-4 may be used: O-e = i(Ro-eJ (4)File No.: 1400287.302 Page 6 of 15 Revision: | p = internal pressure, psig Do = outside diameter, in t = wall thickness, in Rbend = elbow bend radius (27 inches) | ||
0 F0306-01 RI Structural Integrity Associates, IncO where i is the stress intensification factor. From [6, Appendix D], i = 3.98.4.2 Stress Intensity Factor Calculations For LEFM analysis, the stress intensity factor, Ki, for an axial flaw is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below: KI = Kim + Kir (5)where: Kim = (SFm)Fah(7ta/Q) 0'5 SFm = structural factor for membrane stress (see Table 2)F = through-wall shape factor for an axial flaw under hoop stress (given in Appendix I of N-513-3)o-h = hoop stress, ksi a = flaw depth (half flaw length for through-wall flaw), in Q = flaw shape parameter (unity per Appendix I of N-513-3)Kir = Ki from residual stresses at flaw location (assumed negligible). | Ro = outside radius, in 0 = circumferential angle from elbow flank (see Figure 7 in Appendix A) | ||
Only the hoop stress influences the allowable axial flaw length which is a function of pressure and primary bending stress.For LEFM analysis, the stress intensity factor, Ki, for a circumferential flaw is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below: | File No.: 1400287.302 Page 5 of 15 Revision: 0 F0306-01 R1 | ||
Since the load combination for Service Level C and D are equivalent, the more limiting flaw length associated with the Service Level C structural factors are presented. | |||
File No.: 1400287.302 Page 7 of 15 Revision: | tStructuralIntegrity Associates, Inc! | ||
0 F0306-01 RI | h = flexibility characteristic = t*Rbend/(R mean)2 [6] | ||
5.0 RESULTS Table 4 shows the allowable through-wall flaw lengths resulting from the analysis based on a surrounding nominal wall thickness. | Rmean = elbow mean radius, in Mb = primary bending moment, in-lbs I = moment of inertia, in4. | ||
The most limiting flaw length is 8 inches in the circumferential direction. | Note that the first term of Equation I accounts for the hoop stress due to internal pressure and includes a scaling factor to account for the circumferential location of the flaw (assuming uniform thickness, pressure based hoop stress is a maximum at the elbow intrados, while a minimum at the elbow extrados). | ||
The UT results for the leaking elbow are shown in Figure 3 [1]. The leak is easily bounded in the axial and circumferential directions by 8 inches. Thus, the acceptance criteria of Code Case N-513-4 are met.Finally, Paragraph 3.2(d) requires that N-513-3 Equation 9 be satisfied (i.e., the remaining ligament average thickness over the degraded area bounded by the limiting flaw size will resist pressure blowout).The average remaining wall thickness requirement covering the degraded area from Equation 9 is 0.07 inch (using a Chdj = 8 inches). From the inspection data given in Figure 3, only the grids nearest to the leak are less than this value. Thus, this Code Case requirement is met. | At the flank, the pressure based hoop stress is equal to that of straight pipe. For the analysis herein, it is conservative to set 0 = 0 since the flaw is between the flank and extrados as shown on Figure 2. | ||
The second term of Equation 1 accounts for the hoop stress resulting from the axial moments acting to ovalize the elbow. This term is replaced with the scaled primary membrane stress in the hoop direction as discussed in the previous section. | |||
Finally, N-513-4 limits the use of Equation 1 for h> 0.1. For this elbow, h z 0.11. | |||
4.1.2 Axial Stresses For the allowable circumferential flaw length, the axial stress due to pressure, deadweight, seismic, and thermal loading is presented below. For axial membrane stress due to pressure, am, Equation 10 of N-513-4 is used: | |||
B,2tD (2) where Bi is an ASME Section III primary stress index for internal pressure. N-513-4 sets this value to 0.5. | |||
For axial bending stress, ab, due to deadweight and seismic moments, Equation 11 ofN-513-4 may be used: | |||
o-b = B2 (-R -- | |||
b (3) where B2 is an ASME Section III primary stress index for moment loading. From Figure ND-3673.2(b)-I of Reference [5], B2 = 1.30/h 2/3. For this elbow, B2 = 5.74. | |||
For axial bending stress due to thermal moments, (e, Equation 12 of N-513-4 may be used: | |||
O-e =i(Ro-eJ (4) | |||
File No.: 1400287.302 Page 6 of 15 Revision: 0 F0306-01 RI | |||
Structural Integrity Associates, IncO where i is the stress intensification factor. From [6, Appendix D], i = 3.98. | |||
4.2 Stress Intensity Factor Calculations For LEFM analysis, the stress intensity factor, Ki, for an axial flaw is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below: | |||
KI = Kim + Kir (5) where: | |||
Kim = (SFm)Fah(7ta/Q) 0' 5 SFm = structural factor for membrane stress (see Table 2) | |||
F = through-wall shape factor for an axial flaw under hoop stress (given in Appendix I of N-513-3) o-h = hoop stress, ksi a = flaw depth (half flaw length for through-wall flaw), in Q = flaw shape parameter (unity per Appendix I of N-513-3) | |||
Kir = Ki from residual stresses at flaw location (assumed negligible). | |||
Only the hoop stress influences the allowable axial flaw length which is a function of pressure and primary bending stress. | |||
For LEFM analysis, the stress intensity factor, Ki, for a circumferential flaw is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below: | |||
K1 = Kim + Klb + Kir (6) where: | |||
05 Kim = (SFm)Fmam(7ra) " | |||
Fm = through-wall shape factor for a circumferential flaw under membrane stress (given in Appendix I ofN-513-3) am = membrane stress, ksi 0 5 Kib = [(SFb)M + ae]Fb(7ta) | |||
SFb = structural factor for bending stress (see Table 2) ab = bending stress, ksi Ge = thermal stress, ksi Fb = through-wall shape factor for a circumferential flaw under bending stress (given in Appendix I of N-513-3). | |||
Note that the through-wall flaw shape factors are a function of flaw length. | |||
Table 3 shows the specific load combinations considered herein for the allowable circumferential flaw calculations. Since the load combination for Service Level C and D are equivalent, the more limiting flaw length associated with the Service Level C structural factors are presented. | |||
File No.: 1400287.302 Page 7 of 15 Revision: 0 F0306-01 RI | |||
CStructuralIntegrity Associates, Inc! | |||
4.3 Critical Fracture Toughness Determination For LEFM analysis, the static fracture toughness for crack initiation under plane strain conditions, Kic, is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below: | |||
K = ICRE' (7) | |||
V 1000 where: | |||
J= material toughness, in-lb/in 2 E'= E/(1-v 2) | |||
E = Young's modulus, ksi v = Poisson's ratio. | |||
Based on the design input listed previously, Kic is 94.7 ksi-in°5 for both axial and circumferential flaws. | |||
The allowable flaw lengths are determined iteratively by increasing flaw length until the stress intensity factor is equal to the static fracture toughness. | |||
5.0 RESULTS Table 4 shows the allowable through-wall flaw lengths resulting from the analysis based on a surrounding nominal wall thickness. The most limiting flaw length is 8 inches in the circumferential direction. The UT results for the leaking elbow are shown in Figure 3 [1]. The leak is easily bounded in the axial and circumferential directions by 8 inches. Thus, the acceptance criteria of Code Case N-513-4 are met. | |||
Finally, Paragraph 3.2(d) requires that N-513-3 Equation 9 be satisfied (i.e., the remaining ligament average thickness over the degraded area bounded by the limiting flaw size will resist pressure blowout). | |||
The average remaining wall thickness requirement covering the degraded area from Equation 9 is 0.07 inch (using a Chdj = 8 inches). From the inspection data given in Figure 3, only the grids nearest to the leak are less than this value. Thus, this Code Case requirement is met. | |||
==6.0 CONCLUSION== | ==6.0 CONCLUSION== | ||
S The flaw evaluation of the weeping flaw in a 18-inch elbow of the SSW piping at Pilgrim has been evaluated using the methods of a pending revision to Code Case N-513-3 (designated N-513-4) currently in the ASME approval process (N-513-3 does not provide evaluation criteria for flaws in elbows, while N-513-4 does). N-513-4 has not been approved by the ASME or reviewed by the NRC; however, it is recognized in ASME committee that the technical approach is very conservative. | S The flaw evaluation of the weeping flaw in a 18-inch elbow of the SSW piping at Pilgrim has been evaluated using the methods of a pending revision to Code Case N-513-3 (designated N-513-4) currently in the ASME approval process (N-513-3 does not provide evaluation criteria for flaws in elbows, while N-513-4 does). N-513-4 has not been approved by the ASME or reviewed by the NRC; however, it is recognized in ASME committee that the technical approach is very conservative. Table 4 shows the axial and circumferential allowable flaw lengths based on a surrounding nominal wall thickness of 0.312 inch. The most limiting flaw size is 8 inches in the circumferential direction. The leak is easily bounded File No.: 1400287.302 Page 8 of 15 Revision: 0 F0306-01 RI | ||
Table 4 shows the axial and circumferential allowable flaw lengths based on a surrounding nominal wall thickness of 0.312 inch. The most limiting flaw size is 8 inches in the circumferential direction. | |||
The leak is easily bounded File No.: 1400287.302 Page 8 of 15 Revision: | r StructuralIntegrity Associates, Inc! | ||
0 F0306-01 RI r | in the axial and circumferential directions by 8 inches (as shown in Figure 3). Thus, the acceptance criteria of Code Case N-513-4 are met. | ||
File No.: 1400287.302 Page 9 of 15 Revision: 0 F0306-OIRI | |||
VStructural Integrity Associates, Inc! | |||
==7.0 REFERENCES== | ==7.0 REFERENCES== | ||
: 1. Pilgrim NDE Inspection Report, File Name "JF29 4 8 O.dmsdr," February 25, 2014, SI File Number 1400287.201. | : 1. Pilgrim NDE Inspection Report, File Name "JF29 4 8 O.dmsdr," February 25, 2014, SI File Number 1400287.201. | ||
: 2. ASME Code Case N-513-3, "Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Division 1," Cases of ASME Boiler and Pressure Vessel Code, January 26, 2009.3. Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1," Revision 16, Nuclear Regulatory Commission, October, 2010.4. ASME Boiler and Pressure Vessel Code, Section XI, Appendix C, 2001 Edition with addenda through 2003.5. ASME Boiler and Pressure Vessel Code, Section III, Subsection ND, 2004 Edition.6. ANSI B3 1.1, Power Piping, 1967 Edition.7. Entergy Drawing Number M100-7250, Revision E5, "Service Water System E209B SSW Backwash Drain Piping," SI File Number 1400287.201. | : 2. ASME Code Case N-513-3, "Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Division 1," Cases of ASME Boiler and Pressure Vessel Code, January 26, 2009. | ||
: 3. Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1," Revision 16, Nuclear Regulatory Commission, October, 2010. | |||
: 4. ASME Boiler and Pressure Vessel Code, Section XI, Appendix C, 2001 Edition with addenda through 2003. | |||
: 5. ASME Boiler and Pressure Vessel Code, Section III, Subsection ND, 2004 Edition. | |||
: 6. ANSI B3 1.1, Power Piping, 1967 Edition. | |||
: 7. Entergy Drawing Number M100-7250, Revision E5, "Service Water System E209B SSW Backwash Drain Piping," SI File Number 1400287.201. | |||
: 8. Pilgrim Nuclear Power Station Specification Number M300, System 29 Service Water, SI File Number 1400287.201. | : 8. Pilgrim Nuclear Power Station Specification Number M300, System 29 Service Water, SI File Number 1400287.201. | ||
: 9. Pilgrim Nuclear Power Station Pipe Stress Calculation 638, SI File Number 1400057.201. | : 9. Pilgrim Nuclear Power Station Pipe Stress Calculation 638, SI File Number 1400057.201. | ||
: 10. Pipe Fracture Encyclopedia, US Nuclear Regulatory Commission, Volume 1, 1997.11. SI Calculation Number 1400287.301, Revision 0, "Pilgrim Salt Service Water Discharge Piping Elbow (JF29-8-4 Spool) Wall Thinning Stress Analysis." File No.: 1400287.302 Page 10 of 15 Revision: | : 10. Pipe Fracture Encyclopedia, US Nuclear Regulatory Commission, Volume 1, 1997. | ||
0 F0306-01 R1 V | : 11. SI Calculation Number 1400287.301, Revision 0, "Pilgrim Salt Service Water Discharge Piping Elbow (JF29-8-4 Spool) Wall Thinning Stress Analysis." | ||
____.__.Database Reference Temperature | File No.: 1400287.302 Page 10 of 15 Revision: 0 F0306-01 R1 | ||
(°C) Temperature (OF) JIC (kJ/m') JIC (Ibrin/in | |||
V StructuralIntegrity Associates, Inc.m Table 1: Jic Values for A106 Gr. B Carbon Steel from NRC's Pipe Fracture Database [10] | |||
A106 GradeB. '.B.....__ ____.__. | |||
2 Database Reference Temperature (°C) Temperature (OF) JIC (kJ/m') JIC (Ibrin/in ) KIC (ksi-ins ) | |||
2 24 75 97 552 133 2 24 75 336 1919 249 16 25 77 81 464 122 16 25 77 418 2386 277 16 25 77 270 1542 223 16 25 77 193 1104 189 22 24 75 224 1278 203 22 20 68 112 641 144 22 20 68 117 668 147 22 23 73 214 1223 199 22 20 68 167 954 175 22 20 68 223 1271 202 22 20 68 108 617 141 23 52 126 116 663 146 23 23 73 103 590 138 23 23 73 105 600 139 23 23 73 93 528 131 24 23 73 76 431 118 24 23 73 82 469 123 24 57 135 511 293 97 4-25 23 73 77 437 119 25 23 73 70 400 114 25 57 135 62 356 107 90 20 68 235 1342 208 90 20 68 219 1251 201 90 20 68 255 1456 217 90 20 68 281 1605 228 90 20 68 281 1605 228 90 20 68 335 1913 248 90 20 68 421 2404 279 90 20 68 385 2198 266 90 20 68 175 999 180 90 20 68 172 982 178 90 20 68 178 1016 181 90 20 68 214 1222 199 90 20 68 275 1570 225 90 20 68 133 759 157 90 20 68 140 799 161 90 20 68 174 994 179 90 20 68 111 634 143 90 20 68 190 1085 187 90 20 68 71 405 114 90 20 68 110 628 142 90 20 68 104 594 138 90 20 68 104 594 138 90 20 68 97 554, 134 90 20 68 89 508 128 90 20 68 88 502 127 90 20 68 267 1525 222 File No.: 1400287.302 Page 11 of 15 Revision: 0 F0306-OIRI | |||
CStructuralIntegrity Associates, Inc, Table 2: Axial and Circumferential Structural Factors [4] | |||
Alternate methods may be used to calculate the stresses used in evaluation. | Service Level Membrane Stress, SFm Bending Stress, SFb A 2.7 2.3 B 2.4 2.0 C 1.8 1.6 D 1.3 1.4 Table 3: Load Combinations for Circumferential Flaw Analyses Load Combination Service Level P+DW+TH A P+DW+OBE+TH B P+DW+SSE+TH C/D Table 4: Allowable Through-Wall Flaw Lengths (based on t = 0.312") | ||
The hoop stress, o,. for elbow and bent pipe evaluation shall be:-pD.'1[ 2R,_- + Rosin ÷1, o where Rb,, = elbow or bent pipe bend radius 0 = circumferential angle defined in Fig-re 7 h = flexibility characteristic Mb = resultant primary bending moment I = moment of inertia based on evaluation wall tiickness,. | Service Allowable Axial Flaw Allowable Circumferential Level Length (in) Flaw Length (in) | ||
Equation 9 is only applicable for elbows and bent pipe where h > 0 1.The axial membrane pressure stress, o,,_ for elbow and bent pipe evaluation shall be: c B | A 16.0 13.2 B 16.0 8.8 C/D 16.0 8.0 File No.: 1400287.302 Page 12 of 15 Revision: 0 F0306-OIRI | ||
0 F0306-01 RI Figure 7 from N-513-4: FIG. 7 CIRCUMFERENTIAL ANGLE DEFINED extrados File No.: 1400287.302 | |||
CStructuralIntegrity Associates, Inc." | |||
UT Erosion/Corrosion Examination Entergy SiteUnit PNPS / 1 Summary No. SSW Pipe Spool | Figure 1. Pinhole Leak in Service Water Piping, 18-inch Elbow File No.: 1400287.302 Page 13 of 15 Revision: 0 F0306-01R1 | ||
Procedure Rev.: | |||
StructuralIntegrity Associates, Inc! | |||
-Af | |||
ýýY" Toe' 4, | |||
0 C~7~o~4 N4. | |||
Figure 2. Sketch of Leak Location in Service Water Piping, 18-inch Elbow File No.: 1400287.302 Page 14 of 15 Revision: 0 F0306-01Rl | |||
Itj-SIructuralIntegrity Associates, Inc! | |||
LOCATION AJ: AK: AL: AM: AN: AO: AP: AQ: AR: AS: AT: AU: AV: | |||
1 0.396 0.397 0.397 0.380 0.369 0.352 0.348 0.344 0.342 0.335 0.328 0.315 0,328 2 0.398 0.396 0.393 0.371 0,334 0.353 0.347 0.343 0.345 0.341 0.337 0,311 0.325 3 0.393 0.390 0.393 0.369 0.309 0.361 0.347 0.338 0.343 0.335 0.327 0.308 0.326 4 0.387 0.389 0.389 0.383 0.150 0.051 0.109 0.336 0.299 0.336 0.327 0.308 0.318 5 0.386 0.390 0.394 0.192 0.087 0.064 0.083 0.334 0.333 0.313 0.334 0.328 0.298 0.328 0.292 0.315 0.317 0.320 0.323 6 0.389 0.388 0.392 0.108 0.352 0.362 0.332 7 0.390 0.390 0.393 0.390 0.380 0.343 0.342 0.339 0.341 0.296 0.337 0.321 0.323 8 0.385 0.388 0.392 0.388 0.386 0.366 0.360 0.356 0.349 0.349 0.348 0.327 0.326 Figure 3. UT Data (3/4 Inch Grid) for Service Water Piping, 18-inch Elbow File No.: 1400287.302 Page 15 of 15 Revision: 0 F0306-OIRI | |||
Appendix A DRAFT CODE CASE N-513-4 PROCEDURES FOR ELBOW FLAW EVALUATION File No.: 1400287.302 Page A- 1 of A-3 Revision: 0 F0306-OI RI | |||
3.3 Through-wall Flaws in Elbows and Bent Pipe Through-wall flaws in elbows and bent pipe may be evaluated using the straight pipe procedures given in 3 1 or 3.2(d) provided the stresses used in the evaluation are adjusted as described below to accouit for the geometry differences. Alternate methods may be used to calculate the stresses used in evaluation. | |||
The hoop stress, o,. for elbow and bent pipe evaluation shall be: | |||
-pD.'1[ 2R,_- +Rosin ÷1, o where Rb,, = elbow or bent pipe bend radius 0 = circumferential angle defined in Fig-re 7 h = flexibility characteristic Mb = resultant primary bending moment I = moment of inertia based on evaluation wall tiickness,. | |||
Equation 9 is only applicable for elbows and bent pipe where h > 0 1. | |||
The axial membrane pressure stress, o,,_ for elbow and bent pipe evaluation shall be: | |||
c - B (fpB4ID° 2t (10) where B, is a primaty stress index as defined in ASME Section III for the piping item. B, shall be equal to 0.5 for elbows and bent pipe. | |||
The axial bending stress, aob,for elbow and bent pipe evaluation shall be: | |||
where B, is a pimnary stress index as defined in ASME Section III for tile piping item. | |||
The thernal expansion stress, or,. for elbow and bent pipe evaluation shall be: | |||
where i = stress intensification factor as defined in the Code of Record for the piping item Ml = resultant thermal expansion moment File No.: 1400287.302 Page A-2 of A-3 Revision: 0 F0306-01 RI | |||
Figure 7 from N-513-4: | |||
FIG. 7 CIRCUMFERENTIAL ANGLE DEFINED extrados File No.: 1400287.302 Page A-3 of A-3 Revision: 0 F0306-01 RI | |||
ATTACHMENT 5 TO ENTERGY LETTER 2.14.023 PILGRIM RELIEF REQUEST PRR-25 SSW Spool JF 29-8-4 NDE Data Sheet (4 pages) | |||
UT Erosion/Corrosion Examination Entergy SiteUnit PNPS / 1 Procedure: CEP-NDE-0606 Outage No.. NIA Summary No. SSW Pipe Spool Procedure Rev.: 004. Report No.. BOP-UT-14-001 WOrKScopoe BOP Work Order No.: 375247-04 Page 1 of Cooke ASME Sec-XI, 2001-2003 Ada. CatJltem C-HJC7.10 Location "B" Aux Bay D'dwn No M100-7250 | |||
== Description:== | |||
18" Elbow Sst[in ID Service Water System (29) | |||
Component ID Pipe Spool JF29-84 Size/Lengtrr 18" 1 6"-12" Thickness/Diameter Sch..20118" L1i"iati0ol NA Component File No.. NA Start Time 9:45 Finish Time 14:10 Calibration Information Partitioning Information Component Information CaLI=aton T r)ckJ*ss (In) Caorwiabon Times I initiais Component Bg"IVCol/Row EndinQCokRow component Geometry: Pipe Elbow | |||
"*t=* meL..W M. UPST Ext NIA NIA Outside Diameter: 18" Grid Size 314" | |||
.100 0.200 0.100 0.1* S Verify , 12:00 RDA Main UPST. | |||
Man1A8B NIA NWA Max* Thickness: 0.457 Min. Thickness: 0.051 0.200 0.211 Ven-y N2A RDA Main 1A 881 Nominal Thickness 0.312 Tmin. 0.270 0.300 0.299 Verity NIA NIA Main DNST. NIA WA N/A M. DNST EA. NIA MIA Min Thickness Location. 4 AO 0.400 0.400 Verity NWA 0.500 0.500 Final: 14:15 RDA Branch N/A N/A Max. Thickness Location 8Z Branch Ext. NIA NIA Surface Condition. SMOOTH Inbtrument: Transducer: ReferencelSimulator Block: Temp. Tool: | |||
MamltaCtufer GE Manufacturer: KBA Serial No.: 94-5570 Manufacturer Elcometer Mocei USM-GO Serial No. 01550W Type: 0..1-0.5" Serial No.. PNPTEM-288 Senai Nc USMGO12915119 Size 0.375" Freq. 5.0 MH RfSimulator Blok Temp.: 70 FCouplant: | |||
G ai 66 Mo del: 113-50-001 0Type . Ultrage l Range 0.500 # of Elements: 2 Material/Component Temp.: 73 °F Batch No.. 05125 mne-mets, ODStjuctions UT performed do to a through wall hole. See CR-PNP-2014-00815. This is not a Code required exam. | |||
ReitS Accept Reject 7, Eval 41 Avery,.. | |||
ar D. (Rck Ric A 2/6101 ,,,,,,,,,,,,. ,, | |||
ExaminerN/ Level NIA Signatur4' Date Site Review l ___ Signaturel, . ... / Date Other Level NIA Signature Date ANII Review Signature Date N/A . WA | |||
Supplemental Report Report No.: BOP-UT-14-001 Lii/eq~y Page: 2 of 4 Summary No. SSW Pipe Spool File Nam. SpkIl JF29-8-4 Descrption 18" Elbow Creation 0 ate 2/25M2014 Prooe See UT Report Cai Comment See report Inspctor" R AVERY Company Entergy Instrument Type DMS Go Instrument S.N : USMGO12015119 Units INCH Vellocity(in/us) 0.2360 Nuonrer or Readings 468 Nurner of Empties es; 0 N~inuttt Uf OUSIrutS 0 Number of Attachments: 0 Range : 0,406 Points Below MinAlarm : 0 Mean 0 368 Standard Deviation : 0.047 Mnnin.m Vailue 0 051 Minimum Value Loc. .4:AO.1 Maximum Value 0457 Maximum Value Loc. 6Z.1 LOCATIO4 A B" C: D: E: F: G: H: 1: J: K L M: N: | |||
1 0.344 0.348 0.365 0.372 0.374 0.375 0.377 0.373 0.372 0.364 0.361 0.364 0.358 0.359 2 0.346 0.356 0,365 0.370 0.372 0.376 0.373 0.377 0.375 0.370 0.367 0.367 0.364 0 365 3 0.348 0.358 0,363 0.366 0.373 0.376 0.375 0.377 0.376 0.374 0.369 0.367 0.366 0,366 4 0.354 0352 0.365 0369 0,375 0.379 0.381 0.380 0.380 0.380 0.372 0.367 0,366 0.368 5 0,349 0.354 0.366 0,368 0.375 0.378 0.378 0.382 0.382 0.380 0.377 0.372 0.369 0.372 6 0.353 0-357 0364 0.367 0.378 0.378 0.381 0.382 0.366 0.381 0.375 0.372 0.373 0.372 7 0.354 0.357 0365 0.374 0.375 0.380 0.381 0.385 0.381 0.379 0.379 0.371 0.372 0.371 8 0.360 0 359 0.363 0.374 0.373 0.363 0.369 0.382 0.380 0.378 0.377 0.377 0.374 0.372 TOP CiL .o! PIPE Direction of Flow t | |||
-71 | |||
Supplemental Report Report No.: BOP-UT-14-001 Ilderoy Page. 3 of 4 SuImrmary No SSW Pipe Spool 1 | |||
R r I r r r I AA I AB I AC I4 AD r 4 AL 0: ! P: 0: | |||
Q: R: S: U: V: L W: Y: Z': 1AA: IAB: IAC: IAD: AE: | |||
0.380 0.386 0.398 10.415 0.404 1- | |||
~0.372 0.371 0.386 , 0.398 0.400 10,373 10.413 10.419 10.425 0.427 10.421 10.417 10.417 10.413 0-404 0.392 0.398 0.401 I 0.409 I 0.411 I 0.419 I 0.431 0.428 I 0.428 I 0.421 I 0.422 I 0.417 27 0.378 0.385 0.37310.3741038210383 0.380 0.383 | |||
__ 096 0.394 | |||
__ 10.400 0400 0400 I 0.405 | |||
______.1__ 0.401 0.409 1______.1__ | |||
0.415 0.4231 0.410 10.411 0.420 0.429 0.427 0.428910.42830.421 0.437 | |||
__ 0.428 0.422 10.422 0.419 0.417 0.418 0.414 0.405 0.415I040 0.410 | |||
___ 0.404 40.374 0.382 0.383 0.396 10.405 0.409 0.413 0.423 0.427 0.429 0.423 0.421 0.418 0,419 0.415 0.4o3 5 0.378 0.384 0.385 0.400 0.403 0.407 0.412 0.416 0.426 0.428 0.429 0.431 0.427 0.423 0.423 0.421 0.409 6 0.380 0.389 0.393 0.404 0.407 0.414 0.421 0.419 0.429 0.437 0.433 0.430 0.428 0.425 0.422 0.426 0.408 7 0.380 0.387 0.390 0.400 0.406 0.412 0.416 0.419 0.430 0.433 0.430 0.4_30 0.427 0.425 0.423 0.426 0.414 | |||
_0_3830-389 0.395 0.401 0.407 0.412 0.418 0.422 0.426 0.428 0.427 0.457 0.421 0.419 0.422 0.421 0.406 F AG: AH: AI: AJ: AK: AL: AM: AN: AO: AP: AQ: AR- AS: AT: AU: AV: | |||
1 0.400 0.395 0.391 0.396 0.396 0.397 0.397 0.380 0.369 0.352 0.348 0.344 0.342 0.335 0.328 0.315 0.328 2 0.393 0394 0.389 0.397 0.398 0.396 0.393 0.371 0.334 0.353 0.347 0.343 0.345 0.341 0.337 0.311 0.325 3 0.394 0.390 0.388 0.389 0.393 0.390 0.393 0.369 0.309 0.361 0.347 0,338 0.343 0.335 0,327 0.308 0.326 4 0.391 0.385 0.383 0.383 0.387 0.389 0.389 0.383 QAI 0.336 0.299 0.336 0.327 0.308 0.318 0378 0.388 0.380 0.380 0.386 0.390 0.394 Ri ------ 0.-334 0.313 0.328 0.328 0.315 0.320 61 0390 0.380 0.382 0.383 0.389 0.388 0.392 0.352 0.362 0.332 0.333 0.334 0.317 0.323 7 0.398 0.385 0.385 0.380 0.390 0.390 0.393 0.390 0.380 0.343 0.342 0.339 0.341 0.337 0.321 0.323 8 1-0.401 0.392 0.388 0.381 0.385 0.388 0.392 0.388 0.386 0.366 0.360 0.356 0.349 0.349 0.348 0.327 0.326 i AW AX:I AY¥: IAZ: B A:: BB: BC: BD: BE: IBF: BG: BH: Bh: | |||
-7' 2 | |||
-T 0o336 0.337 I | |||
0.345 04 0.341 | |||
' 0.346 0 | |||
I 0.340 0340 I0.344 00345 0.339 | |||
.345~ 0.341 0.339 0.337 0.335 '0.338 0.333 10.332 0.332 0.328 0.331 10.330 0.338 0.341 0.338 0.344 0.336 0.339 0.343 S3 0.341 0.332 0,336 0.343 0.346 0.339 0.337 0.327 0.335 0.334 1 0.336 0.336 0.339 0.344 4 0.326 0.338 0.344 0.343 0.339 0.331 0.336 0.336 0.334 0.336 0.336 0.340 0.349 | |||
.. T . ... .... . .... . ..... .... . ... .. | |||
: 0.331 0.337 0.343 0.345 0.341 0.339 0.333 0.339 0.335 0.335 0.330 0.346 0.343 6 0.336 0.341 0.347 0.348 0-349 0.346 0.339 0.335 0.338 0,343 0.345 0.339 0.345 0__.337 | |||
.332 08-0.347 0.343 0.350 0.380 0.351 10.356 0.348 0.3511 0348 0.347 0.339 0.338 0.335 0.343 0.344 0.343 0.340 0.341 0.339 0.339 0.341 0.343 0.377 0.351 | |||
.- ) 7 | |||
Supplemental Report ,.pArt No BOP-UT-14-O01 4 of 4 EldWeý-"y Page fin, a Ito SM~ Pipe Spool _______ | |||
7 ý, ý}} | |||
Latest revision as of 21:35, 5 February 2020
ML14073A061 | |
Person / Time | |
---|---|
Site: | Pilgrim |
Issue date: | 03/03/2014 |
From: | Tucker J Structural Integrity Associates |
To: | Office of Nuclear Reactor Regulation |
References | |
1400287.302, Rev 0 | |
Download: ML14073A061 (26) | |
Text
ATTACHMENT 4 TO ENTERGY LETTER 2.14.023 PILGRIM RELIEF REQUEST PRR-25 Calculation Cover Page EC # 49514 Flaw Evaluation of SSW Discharge Piping Leaking Elbow Structural Integrity Associates Calculation No. 1400287.302, Rev. 0 (20 Pages)
ATTACHMENT 9.2 ENGINEERING CALCULATION COVER PAGE Sheet 1 of 2
[] ANO-1 13 ANO-2 El GGNS [1 IP-2 [I IP-3 [E PLP f- JAF Z PNPS [1 RBS El VY [I W3 El NP-GGNS-3 [I NP-RBS-3 CALCULATION ()EC # 49514 (2)Page 1 of 20)
COVER PAGE (3) Design Basis Calc. E--YES Z* NO (4) [Z CALCULATION [-*EC Markup
- 15) Calculation No: M1398 (5) Revision: 0 (7)
Title:
Flaw Evaluation of SSW Discharge Piping Leaking Elbow ,1) Editorial DYES Z NO (9) System(s): 29 (10) Review Org (Department):
(ii) Safety Class: (12) Component/Equipment/Structure Type/Number:
Z Safety / Quality Related PIPE / JF29-8-4
[] Augmented Quality Program i-- Non-Safety Related (13) Document Type: CALC (14) Keywords (Description/Topical Codes):
-f JF29-8-4, spool, SIA, Structural Integrity Associates, flaw, leak, rubber lining, 1400287.302, 1400287 REVIEWS (15) Name/Signature/Date (16) Name/Signature/Date (17) Name/Signature/Date Structural Integrity Assoc. John A. Tucker 3. Iq See IAS Responsible Engineer -- Design Verifier Supervisor/Approval Z Reviewer Ei- Comments Attached E- Comments Attached EN-DC-126 R005
ATAHMENT19of3 CALCULATION REFERENCE SHEET Sheet 1 of 3 CALCULATION CALCULATION NO: M1398 REFERENCE SHEET REVISION: 0 I. EC Markups Incorporated (N/A to NP calculations) 1.N/A 2.
3.
4.
5.
- 11. Relationships: Sht Rev Input Output Impact Tracking Doc Doc Y/N No.
- 1. Specification M300 2-12 109 x 0 N
- 2. M100-7250 - 5 x 0 N
- 3. __ 0 0
- 4. _ _0 0
- 5. 0 0 __
III. CROSS
REFERENCES:
- 1. ASME B&PV Code,Section XI, App C, 2001 Edition w/ Add through 2003
- 2. ASME B31.1, Power Piping, 1967 Edition
- 4. Flow of Fluids Through valves, Fittings and Pipe, Crane Co,., Technical Paper No.
410 IV. SOFTWARE USED:
Title:
N/A Version/Release: -- DisklCD No. --
V. DISK/CDS INCLUDED:
Title:
N/A Version/Release Disk/CD No.
VI. OTHER CHANGES:
EN-DC-126 R005
StructuralIntegrity Associates, Inc File No.: 1400287.302 Project No.: 1400287 CALCULATION PACKAGE Quality Program: Z Nuclear E] Commercial PROJECT NAME:
Pilgrim Leaking Elbow Evaluation Support CONTRACT NO.:
10404807, Change Order No. 001 CLIENT: PLANT:
Entergy Nuclear Pilgrim Nuclear Power Station CALCULATION TITLE:
Flaw Evaluation of SSW Discharge Piping Leaking Elbow Document Affected Project Manager Preparer(s) &
Revision Pages Revision Description Approval Checker(s)
Signature & Date Signatures & Date 0 1 - 15 Initial Issue A-i - A-3 Eric Houston Brad Dawson EJH 3/3/14 BPD 3/3/14 Raoul Gnagne LRG 3/3/14 Robert McGill ROM 3/3/14 Page 1 of 15 F0306-01 R1
j StructuralIntegrity Associates, Inc0 Table of Contents 1.0 INTRO DU CTION .................................................................................................... 3 2.0 TECHNICAL APPROACH ..................................................................................... 3 3.0 DESIGN INPUTS / ASSUMPTIONS ...................................................................... 4 4.0 CA LCULA TIO N S ..................................................................................................... 5 4.1 Applied Loads .............................................................................................. 5 4.1.1 Ho op S tress........................................................................................................ 5 4.1.2 A xial Stresses................................................................................................ 6 4.2 Stress Intensity Factor Calculations ............................................................. 7 4.3 Critical Fracture Toughness Determination .................................................. 8 5.0 R E SU LT S ...................................................................................................................... 8 6.0 C O NC LU SIO NS ...................................................................................................... 8 7.0 R E FERE N CE S ...................................................................................................... 10 APPENDIX A DRAFT CODE CASE N-513-4 PROCEDURES FOR ELBOW FLAW EVA LU A TIO N ....................................................................................... A -1 List of Tables Table 1: Jic Values for A106 Gr. B Carbon Steel from NRC's Pipe Fracture Database [10] 11 Table 2: Axial and Circumferential Structural Factors [4] ................................................ 12 Table 3: Load Combinations for Circumferential Flaw Analyses ..................................... 12 Table 4: Allowable Through-Wall Flaw Lengths (based on t = 0.312") ............................ 12 List of Figures Figure 1. Pinhole Leak in Service Water Piping, 18-inch Elbow ....................................... 13 Figure 2. Sketch of Leak Location in Service Water Piping, 18-inch Elbow ................... 14 Figure 3. UT Data (3/4 Inch Grid) for Service Water Piping, 18-inch Elbow ................... 15 File No.: 1400287.302 Page 2 of 15 Revision: 0 F0306-OIRI
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1.0 INTRODUCTION
A weeping flaw, shown on Figure 1, was discovered near the extrados of a 90 degree elbow in the Salt Service Water (SSW) piping at Pilgrim Nuclear Power Station (Pilgrim). The leak is located on the JF29-8-4 pipe spool of the SSW system [1]. Ultrasonic testing has been conducted in order to characterize the flaw [1]. Allowable through-wall flaw lengths are determined using methods consistent with an upcoming revision of Code Case N-513-3 [2] as described below.
2.0 TECHNICAL APPROACH The flaw evaluation herein is based on the criteria prescribed in an upcoming revision of ASME Code Case N-513-3. This Code Case allows for the temporary acceptance of through-wall flaws in moderate energy Class 2 or Class 3 piping. N-513-3 has been conditionally accepted by the NRC with the stipulation that, "The repair or replacement activity temporarily deferred under the provisions of this Code Case shall be performed during the next scheduled outage," and is published in the latest revision of Regulatory Guide 1.147 [3]. N-513-3 allows non-planar, through-wall flaws to be characterized and evaluated as planar (i.e., crack-like), through-wall flaws in the axial and circumferential directions.
The evaluation criteria provided in N-513-3 are only for straight pipe since the technical approach relies on ASME Section XI, Appendix C [4] methods. A new revision of the Code Case (N-513-4) includes rules for the evaluation of piping components such as elbows, branch tees and reducers. Flaws in these components may be evaluated as if in straight pipe provided the stresses used in the evaluation are adjusted to account for geometric differences. For elbows, hoop stress is adjusted by considering flaw location and primary stress due to elbow ovalization from axial loads. For axial stresses, the stress scaling follows the same approach given in ASME Section III, ND-3600 [5] design by rule using stress indices and stress intensification factors for the adjustment. Details are provided in N-513-4 for determining these adjusted stresses.
N-513-4 has not been approved by the ASME or reviewed by the NRC; however, it is recognized in ASME committee that the technical approach is very conservative. Simple treatment of piping component flaw evaluation using hand calculations was an important objective in the development of the approach recognizing the trade-off being conservative results. N-513-4 allows for more sophisticated analysis by the user.
As stated above, Code Case N-513-3 evaluation criteria rely on the methods given in ASME Section XI, Appendix C. Linear Elastic Fracture Mechanics (LEFM) criteria are conservatively employed as described in Article C-7000. Since a through-wall flaw is being evaluated, through-wall shape factors Fm, Fb and F are used which are given in Appendix I of the Code Case. Allowable flaw lengths are determined through iteration comparing calculated stress intensity factors to a critical fracture toughness defined in C-7200 of Section XI, Appendix C.
This evaluation utilizes finite element methods (FEM) to calculate the primary membrane stress in the hoop direction due to ovalization from axial loads. Section 3.3 of the Code Case's new revision states File No.: 1400287.302 Page 3 of 15 Revision: 0 F0306-01RI
jstructural Integrity Associates, IncO that "Alternative methods may be used to calculate the stresses used in evaluation," which justifies the use of FEM techniques.
Details of the Code Case N-513-4 evaluation procedure for elbows are given in Appendix A.
3.0 DESIGN INPUTS / ASSUMPTIONS The SSW Code of Construction is ANSI B31.1 1967 Edition [6].
Based on information provided by Entergy, the 18 inch elbow is located on SSW spool JF29-8-4 [1].
The 90 degree elbow located on JF29-8-4 is a schedule 20, long radius elbow [7]. The design pressure and temperature are 10 psig and 100°F, respectively [8].
The elbow material is ASTM A-234 WPB [7] carbon steel. For the analysis, A106 Gr. B carbon steel is judged to have equivalent material properties. The nominal composition of the two materials is essentially the same and the minimum yield and tensile strengths are the same for both materials. In addition, the longitudinal and transverse elongations are similar between these materials.
The applied moment loadings are obtained from the ME-101 output listings in Reference [9]. Based on information provided by Entergy, the location of interest is node 22. The moments for each load case are provided in three dimensions (MA, MB, and MC), which are combined by square-root-of-the-sum-of-the-squares (SRSS). The resulting SRSS moments at each location along the elbow (beginning, middle, and end) are compared for each loading, and the bounding moment is used in this analysis.
Determination of the fracture toughness, Jic, used in the evaluation is based on Section XI, Appendix C, C-8320 [4], which specifies that 'reasonable lower bound fracture toughness data' may be used to determine the allowable stress intensity factor, Kic. The NRC's Pipe Fracture Encyclopedia [10]
contains numerous CVN test results for A106 Gr. B carbon steel at low temperature, which are reproduced in Table 1. The minimum reported value of 293 in-lb/in 2 is used in the analysis for both axial and circumferential flaws.
Finite element methods are used to determine the primary membrane stress in the hoop direction due to ovalization from axial loads in Reference [11]. A unit moment of 10,000 in-lbs is applied to the FEM and linearized stresses are extracted at paths in the axial direction from the flaw. A stress of 100 psi conservatively bounds the tensile hoop stress reported in Reference [11]. This bounding stress is factored based on the ratio of the applied moment for the applicable service level to the unit moment of 10,000 in-lbs. The factored stress is used as described in Section 4.1.1 below.
The following design inputs are used in this calculation:
- 1. Long radius 900 elbow OD = 18 inches [7]
- 2. Nominal elbow thickness = 0.312 inch (based on Schedule 20 piping [7])
- 3. Design pressure = 10 psig [8]
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- 4. Design temperature = 100'F [8]
- 5. Young's modulus = 27,900 ksi [6, Table C-I]
- 6. Allowable stress = 15 ksi [6, Table A-2]
- 7. Enveloped SRSS Deadweight Moment = 43,973 in-lbs [9]
- 8. Enveloped SRSS OBE Moment = 38,820 in-lbs [9]
- 9. Enveloped SRSS SSE Moment = 72,789 in-lbs [9]
- 10. Enveloped SRSS Thermal Moment = 22,047 in-lbs [9]
- 11. Stress intensification factor, i = 3.98 [6]
- 12. Jhc for axial flaws = 293 in-lb/in2 [4, 10]
- 13. Jic for circumferential flaws = 293 in-lb/in 2 [4, 10]
- 14. Bounding primary membrane stress in the hoop direction due to unit moment load = 100 psi [11]
Note that the wall thickness surrounding the flaw is greater than the elbow nominal thickness [I].
Therefore, the use of the 0.312 inch surrounding wall thickness is considered conservative.
The following assumptions are used in this calculation:
- 1. Poisson's ratio is assumed to be 0.3.
- 2. Due to the flaw remoteness from a weld, residual stress effects are assumed negligible.
- 3. A corrosion allowance is not considered (the ongoing inspection requirements in Code Case N-513-3 address the possibility of flaw growth during the temporary acceptance period).
4.0 CALCULATIONS 4.1 Applied Loads 4.1.1 Hoop Stress For the allowable axial flaw length, the hoop stress, Gh, due to internal pressure and elbow ovalization from the axial moments may be determined from Equation 9 of N-513-4 (see Appendix A):
=( p 0 2Rbend + R.Sin6 1 ( 1.95 )~RMb (1)
=(Pt L2(Rb,,d + Ro sin 0) h 92/3 )1 where:
p = internal pressure, psig Do = outside diameter, in t = wall thickness, in Rbend = elbow bend radius (27 inches)
Ro = outside radius, in 0 = circumferential angle from elbow flank (see Figure 7 in Appendix A)
File No.: 1400287.302 Page 5 of 15 Revision: 0 F0306-01 R1
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h = flexibility characteristic = t*Rbend/(R mean)2 [6]
Rmean = elbow mean radius, in Mb = primary bending moment, in-lbs I = moment of inertia, in4.
Note that the first term of Equation I accounts for the hoop stress due to internal pressure and includes a scaling factor to account for the circumferential location of the flaw (assuming uniform thickness, pressure based hoop stress is a maximum at the elbow intrados, while a minimum at the elbow extrados).
At the flank, the pressure based hoop stress is equal to that of straight pipe. For the analysis herein, it is conservative to set 0 = 0 since the flaw is between the flank and extrados as shown on Figure 2.
The second term of Equation 1 accounts for the hoop stress resulting from the axial moments acting to ovalize the elbow. This term is replaced with the scaled primary membrane stress in the hoop direction as discussed in the previous section.
Finally, N-513-4 limits the use of Equation 1 for h> 0.1. For this elbow, h z 0.11.
4.1.2 Axial Stresses For the allowable circumferential flaw length, the axial stress due to pressure, deadweight, seismic, and thermal loading is presented below. For axial membrane stress due to pressure, am, Equation 10 of N-513-4 is used:
B,2tD (2) where Bi is an ASME Section III primary stress index for internal pressure. N-513-4 sets this value to 0.5.
For axial bending stress, ab, due to deadweight and seismic moments, Equation 11 ofN-513-4 may be used:
o-b = B2 (-R --
b (3) where B2 is an ASME Section III primary stress index for moment loading. From Figure ND-3673.2(b)-I of Reference [5], B2 = 1.30/h 2/3. For this elbow, B2 = 5.74.
For axial bending stress due to thermal moments, (e, Equation 12 of N-513-4 may be used:
O-e =i(Ro-eJ (4)
File No.: 1400287.302 Page 6 of 15 Revision: 0 F0306-01 RI
Structural Integrity Associates, IncO where i is the stress intensification factor. From [6, Appendix D], i = 3.98.
4.2 Stress Intensity Factor Calculations For LEFM analysis, the stress intensity factor, Ki, for an axial flaw is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below:
KI = Kim + Kir (5) where:
Kim = (SFm)Fah(7ta/Q) 0' 5 SFm = structural factor for membrane stress (see Table 2)
F = through-wall shape factor for an axial flaw under hoop stress (given in Appendix I of N-513-3) o-h = hoop stress, ksi a = flaw depth (half flaw length for through-wall flaw), in Q = flaw shape parameter (unity per Appendix I of N-513-3)
Kir = Ki from residual stresses at flaw location (assumed negligible).
Only the hoop stress influences the allowable axial flaw length which is a function of pressure and primary bending stress.
For LEFM analysis, the stress intensity factor, Ki, for a circumferential flaw is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below:
K1 = Kim + Klb + Kir (6) where:
05 Kim = (SFm)Fmam(7ra) "
Fm = through-wall shape factor for a circumferential flaw under membrane stress (given in Appendix I ofN-513-3) am = membrane stress, ksi 0 5 Kib = [(SFb)M + ae]Fb(7ta)
SFb = structural factor for bending stress (see Table 2) ab = bending stress, ksi Ge = thermal stress, ksi Fb = through-wall shape factor for a circumferential flaw under bending stress (given in Appendix I of N-513-3).
Note that the through-wall flaw shape factors are a function of flaw length.
Table 3 shows the specific load combinations considered herein for the allowable circumferential flaw calculations. Since the load combination for Service Level C and D are equivalent, the more limiting flaw length associated with the Service Level C structural factors are presented.
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4.3 Critical Fracture Toughness Determination For LEFM analysis, the static fracture toughness for crack initiation under plane strain conditions, Kic, is taken from Article C-7000 [4] as prescribed by N-513-3 and is given below:
K = ICRE' (7)
V 1000 where:
J= material toughness, in-lb/in 2 E'= E/(1-v 2)
E = Young's modulus, ksi v = Poisson's ratio.
Based on the design input listed previously, Kic is 94.7 ksi-in°5 for both axial and circumferential flaws.
The allowable flaw lengths are determined iteratively by increasing flaw length until the stress intensity factor is equal to the static fracture toughness.
5.0 RESULTS Table 4 shows the allowable through-wall flaw lengths resulting from the analysis based on a surrounding nominal wall thickness. The most limiting flaw length is 8 inches in the circumferential direction. The UT results for the leaking elbow are shown in Figure 3 [1]. The leak is easily bounded in the axial and circumferential directions by 8 inches. Thus, the acceptance criteria of Code Case N-513-4 are met.
Finally, Paragraph 3.2(d) requires that N-513-3 Equation 9 be satisfied (i.e., the remaining ligament average thickness over the degraded area bounded by the limiting flaw size will resist pressure blowout).
The average remaining wall thickness requirement covering the degraded area from Equation 9 is 0.07 inch (using a Chdj = 8 inches). From the inspection data given in Figure 3, only the grids nearest to the leak are less than this value. Thus, this Code Case requirement is met.
6.0 CONCLUSION
S The flaw evaluation of the weeping flaw in a 18-inch elbow of the SSW piping at Pilgrim has been evaluated using the methods of a pending revision to Code Case N-513-3 (designated N-513-4) currently in the ASME approval process (N-513-3 does not provide evaluation criteria for flaws in elbows, while N-513-4 does). N-513-4 has not been approved by the ASME or reviewed by the NRC; however, it is recognized in ASME committee that the technical approach is very conservative. Table 4 shows the axial and circumferential allowable flaw lengths based on a surrounding nominal wall thickness of 0.312 inch. The most limiting flaw size is 8 inches in the circumferential direction. The leak is easily bounded File No.: 1400287.302 Page 8 of 15 Revision: 0 F0306-01 RI
r StructuralIntegrity Associates, Inc!
in the axial and circumferential directions by 8 inches (as shown in Figure 3). Thus, the acceptance criteria of Code Case N-513-4 are met.
File No.: 1400287.302 Page 9 of 15 Revision: 0 F0306-OIRI
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7.0 REFERENCES
- 1. Pilgrim NDE Inspection Report, File Name "JF29 4 8 O.dmsdr," February 25, 2014, SI File Number 1400287.201.
- 2. ASME Code Case N-513-3, "Evaluation Criteria for Temporary Acceptance of Flaws in Moderate Energy Class 2 or 3 Piping Section XI, Division 1," Cases of ASME Boiler and Pressure Vessel Code, January 26, 2009.
- 3. Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability, ASME Section XI, Division 1," Revision 16, Nuclear Regulatory Commission, October, 2010.
- 4. ASME Boiler and Pressure Vessel Code,Section XI, Appendix C, 2001 Edition with addenda through 2003.
- 5. ASME Boiler and Pressure Vessel Code,Section III, Subsection ND, 2004 Edition.
- 6. ANSI B3 1.1, Power Piping, 1967 Edition.
- 7. Entergy Drawing Number M100-7250, Revision E5, "Service Water System E209B SSW Backwash Drain Piping," SI File Number 1400287.201.
- 8. Pilgrim Nuclear Power Station Specification Number M300, System 29 Service Water, SI File Number 1400287.201.
- 9. Pilgrim Nuclear Power Station Pipe Stress Calculation 638, SI File Number 1400057.201.
- 10. Pipe Fracture Encyclopedia, US Nuclear Regulatory Commission, Volume 1, 1997.
- 11. SI Calculation Number 1400287.301, Revision 0, "Pilgrim Salt Service Water Discharge Piping Elbow (JF29-8-4 Spool) Wall Thinning Stress Analysis."
File No.: 1400287.302 Page 10 of 15 Revision: 0 F0306-01 R1
V StructuralIntegrity Associates, Inc.m Table 1: Jic Values for A106 Gr. B Carbon Steel from NRC's Pipe Fracture Database [10]
A106 GradeB. '.B.....__ ____.__.
2 Database Reference Temperature (°C) Temperature (OF) JIC (kJ/m') JIC (Ibrin/in ) KIC (ksi-ins )
2 24 75 97 552 133 2 24 75 336 1919 249 16 25 77 81 464 122 16 25 77 418 2386 277 16 25 77 270 1542 223 16 25 77 193 1104 189 22 24 75 224 1278 203 22 20 68 112 641 144 22 20 68 117 668 147 22 23 73 214 1223 199 22 20 68 167 954 175 22 20 68 223 1271 202 22 20 68 108 617 141 23 52 126 116 663 146 23 23 73 103 590 138 23 23 73 105 600 139 23 23 73 93 528 131 24 23 73 76 431 118 24 23 73 82 469 123 24 57 135 511 293 97 4-25 23 73 77 437 119 25 23 73 70 400 114 25 57 135 62 356 107 90 20 68 235 1342 208 90 20 68 219 1251 201 90 20 68 255 1456 217 90 20 68 281 1605 228 90 20 68 281 1605 228 90 20 68 335 1913 248 90 20 68 421 2404 279 90 20 68 385 2198 266 90 20 68 175 999 180 90 20 68 172 982 178 90 20 68 178 1016 181 90 20 68 214 1222 199 90 20 68 275 1570 225 90 20 68 133 759 157 90 20 68 140 799 161 90 20 68 174 994 179 90 20 68 111 634 143 90 20 68 190 1085 187 90 20 68 71 405 114 90 20 68 110 628 142 90 20 68 104 594 138 90 20 68 104 594 138 90 20 68 97 554, 134 90 20 68 89 508 128 90 20 68 88 502 127 90 20 68 267 1525 222 File No.: 1400287.302 Page 11 of 15 Revision: 0 F0306-OIRI
CStructuralIntegrity Associates, Inc, Table 2: Axial and Circumferential Structural Factors [4]
Service Level Membrane Stress, SFm Bending Stress, SFb A 2.7 2.3 B 2.4 2.0 C 1.8 1.6 D 1.3 1.4 Table 3: Load Combinations for Circumferential Flaw Analyses Load Combination Service Level P+DW+TH A P+DW+OBE+TH B P+DW+SSE+TH C/D Table 4: Allowable Through-Wall Flaw Lengths (based on t = 0.312")
Service Allowable Axial Flaw Allowable Circumferential Level Length (in) Flaw Length (in)
A 16.0 13.2 B 16.0 8.8 C/D 16.0 8.0 File No.: 1400287.302 Page 12 of 15 Revision: 0 F0306-OIRI
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Figure 1. Pinhole Leak in Service Water Piping, 18-inch Elbow File No.: 1400287.302 Page 13 of 15 Revision: 0 F0306-01R1
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-Af
ýýY" Toe' 4,
0 C~7~o~4 N4.
Figure 2. Sketch of Leak Location in Service Water Piping, 18-inch Elbow File No.: 1400287.302 Page 14 of 15 Revision: 0 F0306-01Rl
Itj-SIructuralIntegrity Associates, Inc!
LOCATION AJ: AK: AL: AM: AN: AO: AP: AQ: AR: AS: AT: AU: AV:
1 0.396 0.397 0.397 0.380 0.369 0.352 0.348 0.344 0.342 0.335 0.328 0.315 0,328 2 0.398 0.396 0.393 0.371 0,334 0.353 0.347 0.343 0.345 0.341 0.337 0,311 0.325 3 0.393 0.390 0.393 0.369 0.309 0.361 0.347 0.338 0.343 0.335 0.327 0.308 0.326 4 0.387 0.389 0.389 0.383 0.150 0.051 0.109 0.336 0.299 0.336 0.327 0.308 0.318 5 0.386 0.390 0.394 0.192 0.087 0.064 0.083 0.334 0.333 0.313 0.334 0.328 0.298 0.328 0.292 0.315 0.317 0.320 0.323 6 0.389 0.388 0.392 0.108 0.352 0.362 0.332 7 0.390 0.390 0.393 0.390 0.380 0.343 0.342 0.339 0.341 0.296 0.337 0.321 0.323 8 0.385 0.388 0.392 0.388 0.386 0.366 0.360 0.356 0.349 0.349 0.348 0.327 0.326 Figure 3. UT Data (3/4 Inch Grid) for Service Water Piping, 18-inch Elbow File No.: 1400287.302 Page 15 of 15 Revision: 0 F0306-OIRI
Appendix A DRAFT CODE CASE N-513-4 PROCEDURES FOR ELBOW FLAW EVALUATION File No.: 1400287.302 Page A- 1 of A-3 Revision: 0 F0306-OI RI
3.3 Through-wall Flaws in Elbows and Bent Pipe Through-wall flaws in elbows and bent pipe may be evaluated using the straight pipe procedures given in 3 1 or 3.2(d) provided the stresses used in the evaluation are adjusted as described below to accouit for the geometry differences. Alternate methods may be used to calculate the stresses used in evaluation.
The hoop stress, o,. for elbow and bent pipe evaluation shall be:
-pD.'1[ 2R,_- +Rosin ÷1, o where Rb,, = elbow or bent pipe bend radius 0 = circumferential angle defined in Fig-re 7 h = flexibility characteristic Mb = resultant primary bending moment I = moment of inertia based on evaluation wall tiickness,.
Equation 9 is only applicable for elbows and bent pipe where h > 0 1.
The axial membrane pressure stress, o,,_ for elbow and bent pipe evaluation shall be:
c - B (fpB4ID° 2t (10) where B, is a primaty stress index as defined in ASME Section III for the piping item. B, shall be equal to 0.5 for elbows and bent pipe.
The axial bending stress, aob,for elbow and bent pipe evaluation shall be:
where B, is a pimnary stress index as defined in ASME Section III for tile piping item.
The thernal expansion stress, or,. for elbow and bent pipe evaluation shall be:
where i = stress intensification factor as defined in the Code of Record for the piping item Ml = resultant thermal expansion moment File No.: 1400287.302 Page A-2 of A-3 Revision: 0 F0306-01 RI
Figure 7 from N-513-4:
FIG. 7 CIRCUMFERENTIAL ANGLE DEFINED extrados File No.: 1400287.302 Page A-3 of A-3 Revision: 0 F0306-01 RI
ATTACHMENT 5 TO ENTERGY LETTER 2.14.023 PILGRIM RELIEF REQUEST PRR-25 SSW Spool JF 29-8-4 NDE Data Sheet (4 pages)
UT Erosion/Corrosion Examination Entergy SiteUnit PNPS / 1 Procedure: CEP-NDE-0606 Outage No.. NIA Summary No. SSW Pipe Spool Procedure Rev.: 004. Report No.. BOP-UT-14-001 WOrKScopoe BOP Work Order No.: 375247-04 Page 1 of Cooke ASME Sec-XI, 2001-2003 Ada. CatJltem C-HJC7.10 Location "B" Aux Bay D'dwn No M100-7250
Description:
18" Elbow Sst[in ID Service Water System (29)
Component ID Pipe Spool JF29-84 Size/Lengtrr 18" 1 6"-12" Thickness/Diameter Sch..20118" L1i"iati0ol NA Component File No.. NA Start Time 9:45 Finish Time 14:10 Calibration Information Partitioning Information Component Information CaLI=aton T r)ckJ*ss (In) Caorwiabon Times I initiais Component Bg"IVCol/Row EndinQCokRow component Geometry: Pipe Elbow
"*t=* meL..W M. UPST Ext NIA NIA Outside Diameter: 18" Grid Size 314"
.100 0.200 0.100 0.1* S Verify , 12:00 RDA Main UPST.
Man1A8B NIA NWA Max* Thickness: 0.457 Min. Thickness: 0.051 0.200 0.211 Ven-y N2A RDA Main 1A 881 Nominal Thickness 0.312 Tmin. 0.270 0.300 0.299 Verity NIA NIA Main DNST. NIA WA N/A M. DNST EA. NIA MIA Min Thickness Location. 4 AO 0.400 0.400 Verity NWA 0.500 0.500 Final: 14:15 RDA Branch N/A N/A Max. Thickness Location 8Z Branch Ext. NIA NIA Surface Condition. SMOOTH Inbtrument: Transducer: ReferencelSimulator Block: Temp. Tool:
MamltaCtufer GE Manufacturer: KBA Serial No.: 94-5570 Manufacturer Elcometer Mocei USM-GO Serial No. 01550W Type: 0..1-0.5" Serial No.. PNPTEM-288 Senai Nc USMGO12915119 Size 0.375" Freq. 5.0 MH RfSimulator Blok Temp.: 70 FCouplant:
G ai 66 Mo del: 113-50-001 0Type . Ultrage l Range 0.500 # of Elements: 2 Material/Component Temp.: 73 °F Batch No.. 05125 mne-mets, ODStjuctions UT performed do to a through wall hole. See CR-PNP-2014-00815. This is not a Code required exam.
ReitS Accept Reject 7, Eval 41 Avery,..
ar D. (Rck Ric A 2/6101 ,,,,,,,,,,,,. ,,
ExaminerN/ Level NIA Signatur4' Date Site Review l ___ Signaturel, . ... / Date Other Level NIA Signature Date ANII Review Signature Date N/A . WA
Supplemental Report Report No.: BOP-UT-14-001 Lii/eq~y Page: 2 of 4 Summary No. SSW Pipe Spool File Nam. SpkIl JF29-8-4 Descrption 18" Elbow Creation 0 ate 2/25M2014 Prooe See UT Report Cai Comment See report Inspctor" R AVERY Company Entergy Instrument Type DMS Go Instrument S.N : USMGO12015119 Units INCH Vellocity(in/us) 0.2360 Nuonrer or Readings 468 Nurner of Empties es; 0 N~inuttt Uf OUSIrutS 0 Number of Attachments: 0 Range : 0,406 Points Below MinAlarm : 0 Mean 0 368 Standard Deviation : 0.047 Mnnin.m Vailue 0 051 Minimum Value Loc. .4:AO.1 Maximum Value 0457 Maximum Value Loc. 6Z.1 LOCATIO4 A B" C: D: E: F: G: H: 1: J: K L M: N:
1 0.344 0.348 0.365 0.372 0.374 0.375 0.377 0.373 0.372 0.364 0.361 0.364 0.358 0.359 2 0.346 0.356 0,365 0.370 0.372 0.376 0.373 0.377 0.375 0.370 0.367 0.367 0.364 0 365 3 0.348 0.358 0,363 0.366 0.373 0.376 0.375 0.377 0.376 0.374 0.369 0.367 0.366 0,366 4 0.354 0352 0.365 0369 0,375 0.379 0.381 0.380 0.380 0.380 0.372 0.367 0,366 0.368 5 0,349 0.354 0.366 0,368 0.375 0.378 0.378 0.382 0.382 0.380 0.377 0.372 0.369 0.372 6 0.353 0-357 0364 0.367 0.378 0.378 0.381 0.382 0.366 0.381 0.375 0.372 0.373 0.372 7 0.354 0.357 0365 0.374 0.375 0.380 0.381 0.385 0.381 0.379 0.379 0.371 0.372 0.371 8 0.360 0 359 0.363 0.374 0.373 0.363 0.369 0.382 0.380 0.378 0.377 0.377 0.374 0.372 TOP CiL .o! PIPE Direction of Flow t
-71
Supplemental Report Report No.: BOP-UT-14-001 Ilderoy Page. 3 of 4 SuImrmary No SSW Pipe Spool 1
R r I r r r I AA I AB I AC I4 AD r 4 AL 0: ! P: 0:
Q: R: S: U: V: L W: Y: Z': 1AA: IAB: IAC: IAD: AE:
0.380 0.386 0.398 10.415 0.404 1-
~0.372 0.371 0.386 , 0.398 0.400 10,373 10.413 10.419 10.425 0.427 10.421 10.417 10.417 10.413 0-404 0.392 0.398 0.401 I 0.409 I 0.411 I 0.419 I 0.431 0.428 I 0.428 I 0.421 I 0.422 I 0.417 27 0.378 0.385 0.37310.3741038210383 0.380 0.383
__ 096 0.394
__ 10.400 0400 0400 I 0.405
______.1__ 0.401 0.409 1______.1__
0.415 0.4231 0.410 10.411 0.420 0.429 0.427 0.428910.42830.421 0.437
__ 0.428 0.422 10.422 0.419 0.417 0.418 0.414 0.405 0.415I040 0.410
___ 0.404 40.374 0.382 0.383 0.396 10.405 0.409 0.413 0.423 0.427 0.429 0.423 0.421 0.418 0,419 0.415 0.4o3 5 0.378 0.384 0.385 0.400 0.403 0.407 0.412 0.416 0.426 0.428 0.429 0.431 0.427 0.423 0.423 0.421 0.409 6 0.380 0.389 0.393 0.404 0.407 0.414 0.421 0.419 0.429 0.437 0.433 0.430 0.428 0.425 0.422 0.426 0.408 7 0.380 0.387 0.390 0.400 0.406 0.412 0.416 0.419 0.430 0.433 0.430 0.4_30 0.427 0.425 0.423 0.426 0.414
_0_3830-389 0.395 0.401 0.407 0.412 0.418 0.422 0.426 0.428 0.427 0.457 0.421 0.419 0.422 0.421 0.406 F AG: AH: AI: AJ: AK: AL: AM: AN: AO: AP: AQ: AR- AS: AT: AU: AV:
1 0.400 0.395 0.391 0.396 0.396 0.397 0.397 0.380 0.369 0.352 0.348 0.344 0.342 0.335 0.328 0.315 0.328 2 0.393 0394 0.389 0.397 0.398 0.396 0.393 0.371 0.334 0.353 0.347 0.343 0.345 0.341 0.337 0.311 0.325 3 0.394 0.390 0.388 0.389 0.393 0.390 0.393 0.369 0.309 0.361 0.347 0,338 0.343 0.335 0,327 0.308 0.326 4 0.391 0.385 0.383 0.383 0.387 0.389 0.389 0.383 QAI 0.336 0.299 0.336 0.327 0.308 0.318 0378 0.388 0.380 0.380 0.386 0.390 0.394 Ri ------ 0.-334 0.313 0.328 0.328 0.315 0.320 61 0390 0.380 0.382 0.383 0.389 0.388 0.392 0.352 0.362 0.332 0.333 0.334 0.317 0.323 7 0.398 0.385 0.385 0.380 0.390 0.390 0.393 0.390 0.380 0.343 0.342 0.339 0.341 0.337 0.321 0.323 8 1-0.401 0.392 0.388 0.381 0.385 0.388 0.392 0.388 0.386 0.366 0.360 0.356 0.349 0.349 0.348 0.327 0.326 i AW AX:I AY¥: IAZ: B A:: BB: BC: BD: BE: IBF: BG: BH: Bh:
-7' 2
-T 0o336 0.337 I
0.345 04 0.341
' 0.346 0
I 0.340 0340 I0.344 00345 0.339
.345~ 0.341 0.339 0.337 0.335 '0.338 0.333 10.332 0.332 0.328 0.331 10.330 0.338 0.341 0.338 0.344 0.336 0.339 0.343 S3 0.341 0.332 0,336 0.343 0.346 0.339 0.337 0.327 0.335 0.334 1 0.336 0.336 0.339 0.344 4 0.326 0.338 0.344 0.343 0.339 0.331 0.336 0.336 0.334 0.336 0.336 0.340 0.349
.. T . ... .... . .... . ..... .... . ... ..
- 0.331 0.337 0.343 0.345 0.341 0.339 0.333 0.339 0.335 0.335 0.330 0.346 0.343 6 0.336 0.341 0.347 0.348 0-349 0.346 0.339 0.335 0.338 0,343 0.345 0.339 0.345 0__.337
.332 08-0.347 0.343 0.350 0.380 0.351 10.356 0.348 0.3511 0348 0.347 0.339 0.338 0.335 0.343 0.344 0.343 0.340 0.341 0.339 0.339 0.341 0.343 0.377 0.351
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