CNRO-2003-00020, Arkansas, Unit 2 and Waterford, Unit 3, Relaxation Requests to NRC Order EA-03-009

Arkansas, Unit 2 and Waterford, Unit 3, Relaxation Requests to NRC Order EA-03-009

ML031690568
Person / Time
Site:	Arkansas Nuclear, Waterford
Issue date:	06/11/2003
From:	Krupa M Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CNRO-2003-00020, EA-03-009 M-EP-2003-002
Download: ML031690568 (85)

Text

Entergy Operations, Inc.

'E t&§ta 1340 Echelon Parkway Jackson, MS 39213-8298 Tel 601 368 5758 Michael A. Krupa Director Nuclear Safety & Licensing CNRO-2003-00020 June 11, 2003 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

Entergy Operations, Inc.

Relaxation Requests to NRC Order EA-03-009 Arkansas Nuclear One, Unit 2 Docket No. 50-368 License No. NPF-6 Waterford Steam Electric Station, Unit 3 Docket No. 50-382 License No. NPF-38

REFERENCE:

NRC Order EA-03-009, "Issuance of Order Establishing Interim Inspection Requirements for Reactor Pressure Vessel Heads at Pressurized Water Reactors," dated February 11, 2003

Dear Sir or Madam:

Pursuant to Section IV.F of NRC Order EA-03-009, Entergy Operations, Inc. (Entergy) requests relaxation from Section IV.C(1)(b) of the Order for Arkansas Nuclear One, Unit 2 (ANO-2) and Waterford Steam Electric Station, Unit 3 (Waterford 3). Specifically, the bottom of the ANO-2 and Waterford 3 control element assembly (CEA) drive nozzles contain threads that cannot be effectively examined in accordance with Section IV.C(1)(b).

Enclosures 1 and 2 contain the relaxation requests for ANO-2 and Waterford 3, respectively.

Enclosure 3 contains a copy of the fracture mechanics analyses report (Engineering Report M-EP-2003-002) that supports the relaxation requests. Enclosure 4 contains Appendix I while Enclosure 5 contains Appendices II and IlIl of this report.

Entergy considers the information contained in Enclosure 5 to be proprietary and confidential in accordance with 10 CFR 2.790(a)(4) and 10 CFR 9.17(a)(4). As such, Entergy requests this information be withheld from public disclosure. The affidavit supporting this request is provided in Enclosure 6. Because the vast majority of the information contained in these appendices is considered proprietary, Entergy considers it impractical to provide non-proprietary versions.

CNRO-2003-00020 Page 2 of 2 The NRC has approved similar requests for other nuclear plants.

Entergy requests approval of the proposed relaxation requests by August 1, 2003 in order to support activities scheduled during the upcoming fall 2003 refueling outages at ANO-2 and Waterford 3.

This letter contains no new commitments.

If you have any questions or require additional information, please contact Guy Davant at (601) 368-5756.

Sincerely, MAK/GHDtbal

Enclosures:

1. Relaxation Request for Arkansas Nuclear One, Unit 2

2. Relaxation Request for Waterford Steam Electric Station, Unit 3

3. Engineering Report M-EP-2003-02

4. Appendix I of Engineering Report M-EP-2003-002the Fracture Mechanics Analyses Report

5. Proprietary Information - Appendices II and IlIl of the Fracture Mechanics Analyses Report

6. Affidavit for Withholding Information from Public Disclosure cc: Mr. C. G. Anderson (ANO)

Mr. W. A. Eaton (ECH)

Mr. G. D. Pierce (ECH)

Mr. J. E. Venable (W3)

Mr. T. W. Alexion, NRR Project Manager (ANO-2)

Mr. R. L. Bywater, NRC Senior Resident Inspector (ANO)

Mr. T. P. Gwynn, NRC Region IV Regional Administrator Mr. M. C. Hay, NRC Senior Resident Inspector (W3)

Mr. N. Kalyanam, NRR Project Manager (W3)

ENCLOSURE I CNRO-2003-00020 RELAXATION REQUEST FOR ARKANSAS NUCLEAR ONE, UNIT 2

ENTERGY OPERATIONS, INC.

ARKANSAS NUCLEAR ONE, UNIT 2 COMPONENTIEXAMINATION Component/Number: 2R-1

Description:

Reactor Pressure Vessel (RPV) head penetration nozzles Code Class: 1

References:

1. NRC Order EA-03-009, Issuance of Order Establishing Interim Inspection Requirements for Reactor Pressure Vessel Heads at Pressurized Water Reactors

2. Letter 2CAN020304 from Entergy Operations, Inc. to the NRC, Entergy Operations, Inc. - Answer to Issuance of Order Establishing Interim Inspection Requirements for Reactor Pressure Vessel Heads at pressurized Water Reactors", dated February 28, 2003

3. Engineering Report M-EP-2003-002, Fracture Mechanics Analysis for Primary Water Stress Corrosion Crack (PWSCC) Growth in the Un-Inspected Regions of the Control Element Drive Mechanism (CEDM) Nozzles at Arkansas Nuclear One Unit 2 & Waterford Steam Electric Station Unit 3

4. EPRI Material Reliability Program Crack Growth Rates for Evaluating Primary Water Stress Corrosion Cracking (PWSCC) of Thick-Wall Alloy 600 Materials (MRP-55)

Revision 1 Unit: Arkansas Nuclear One Unit 2 (ANO-2)

Inspection Interval: Third (3rd) 10-Year Interval

11. REQUIREMENTS The NRC issued Order EA-03-009 (the Order) that modified the current licenses at nuclear facilities utilizing pressurized water reactors (PWRs), which includes Arkansas Nuclear One, Unit 2 (ANO-2). The NRC Order establishes inspection requirements for RPV head penetration nozzles. ANO-2 is categorized as a High" PWSCC susceptibility plant based on an effective degradation year (EDY) greater than 12. According to Section IV.C.1(b) of the Order, RPV head penetration nozzles in the "High" PWSCC susceptibility category shall be inspected using either of the following methods each refueling outage:

(i) Ultrasonic testing of each RPV head penetration nozzle (i.e., nozzle base material) from two (2) inches above the J-groove weld to the bottom of the nozzle and an assessment to determine if leakage has occurred into the interference fit zone.

Page 1 of 10

(ii) Eddy current testing or dye penetrant testing of the wetted surface of each J-groove weld and RPV head penetration nozzle base material to at least two (2) inches above the J-groove weld.

Ill. PROPOSED ALTERNATIVE A. Background The ANO-2 RPV head has ninety (90) penetration nozzles that include eighty-one (81) Control Element Drive Mechanism (CEDM) nozzles, eight (8) Incore Instrument (ICI) nozzles, and one (1) vent line nozzle. Nozzle dimensions are identified below.

RPV Penetration Nozzle Dimensions Nozzle Outside Dia. Inside Dia. Thickness CEDM 4.050 inches 2.718 inches 0.6660 inches ICI 5.563 inches 4.750 inches 0.4065 inches Vent Line 1.050 inches 0.742 inches 0.1540 inches Entergy Operations, Inc. (Entergy) plans to inspect RPV head penetration nozzles at ANO-2 using the ultrasonic testing (UT) method in accordance with Section IV.C.1(b)(i) of the Order. However, due to nozzle configuration at the guide cone connection and UT coverage limitations, CEDM nozzles cannot be inspected to the bottom as required by the Order. Therefore, Entergy requests relaxation from the UT coverage requirements of Section IV.C.1(b)(i) of the Order and proposes an alternative in Section II.B, below.

This relaxation request does not apply to ICI nozzles or the vent line nozzle due to different configurations.

B. Proposed Alternative Paragraph IV.C.1(b)(i) of the Order requires that the UT inspection of each RPV head penetration nozzle extend "from two (2) inches above the J-groove weld to the bottom of the nozzle." Entergy requests relaxation from this provision for CEDM nozzles and proposes the following alternative:

• CEDM nozzles (i.e., nozzle base material) shall be ultrasonically examined from two (2) inches above the J-groove weld to 1.544 inches above the bottom of the nozzle. A fracture mechanics evaluation has been performed and demonstrates that residual stresses in the bottom portion of the nozzle are insufficient to cause an axial flaw to propagate into the pressure boundary region of the nozzle along the J-groove weld (nozzle J-groove weld region) prior to re-inspection during the next refueling outage.

Page 2 of 10

IV. BASIS FOR PROPOSED ALTERNATIVE A. Background UT inspection of CEDM nozzles will be performed using a combination of time-of-flight diffraction (TOFD) and standard 0 pulse-echo techniques. The TOFD approach utilizes two pairs of 0.250-inch diameter, 550 refracted-longitudinal wave transducers aimed at each other. One of the transducers sends sound into the inspection volume while the other receives the reflected and diffracted signals as they interact with the material. There will be one TOFD pair looking in the axial direction of the penetration nozzle tube and one TOFD pair looking in the circumferential direction of the tube. The TOFD technique is primarily used to detect and characterize planer-type defects within the full volume of the tube.

The standard 0 pulse-echo ultrasonic approach utilizes two 0.250-inch diameter straight beam transducers. One transducer uses a center frequency of 2.25 MHz while the other uses a frequency of 5.0 MHz. The 0° technique is primarily used to plot the penetration tube outside diameter location and the J-groove attachment weld location, which are used to characterize the orientation and size of the defect.

Additionally, the 0 technique is capable of locating and sizing any laminar-type defects that may be encountered.

The UT inspection procedures and techniques to be utilized at ANO-2 have been satisfactorily demonstrated under the EPRI Materials Reliability Program (MRP)

Inspection Demonstration Program.

B. Hardship and Unusual Difficulty Section VI.C.1(b)(i) of the Order requires UT inspection of RPV head penetration nozzles (i.e., nozzle base material) from two (2) inches above the J-groove weld to the bottom of the nozzle. However, a UT inspection of CEDM nozzles at ANO-2 can only be performed from 2 inches above the J-groove weld down to a point approximately 1.544 inches above the bottom of the nozzle. The reduced coverage is due to CEDM nozzle configuration (1.344 inches) and inspection probe design limitations (0.200 inch) as described below.

• Nozzle Configuration Limitation Guide cones (funnels) are attached to the bottoms of the ANO-2 CEDM nozzles. The funnels are connected to the CEDM nozzles by threaded connections - the CEDM nozzles have intemal threads while the funnels have external threads. The length of the threaded connection region is 1.25 inches.

Additionally, a 450 chamfer exists immediately above the threaded connection region. The length of the chamfer region is 0.094 inch. (See Figure 1 for additional details.)

Due to the threaded connection and chamfer region at the bottom of each CEDM nozzle, a meaningful UT examination in that area cannot be performed.

The UT scans of the region are obscured by multiple signals reflected back by the threaded surfaces and chamfer. Therefore, UT of the bottom 1.344 inches of the CEDM nozzles is impractical. To resolve UT limitations due to nozzle configuration, the existing CEDM nozzle-to-funnel threaded connections would Page 3 of 10

have to be eliminated, redesigned, and physically modified to provide for an acceptable UT examination.

• InsDection Probe Blind Zone The inspection probe to be used in the inspection of ANO-2 CEDM nozzles consists of seven (7) individual transducers, as shown in Figure 2. Transducers 1 and 2 perform circumferential scans using TOFD; transducers 3 and 4 perform axial scans using TOFD; transducers 5 and 6 perform a standard 00 scan; and transducer 7 performs eddy current testing (ECT). (Note that the TOFD circumferential scans have demonstrated the capability to detect axial flaws in addition to circumferential flaws.) In order to achieve the maximum ultrasonic inspection coverage, the inspection probe is operated in such a way as to allow transducers 1 and 2 (UT TOFD for circumferential scans) to scan down to the top of the chamfer at the completion of the downward scan.

The inspection probe is designed so that the ultrasonic transducers are slightly recessed into the probe holder. This recess must be filled with water to provide coupling between the transducer and the component (i.e., nozzle wall).

Because of this design, the complete diameter of the transducer must fully contact the inspection surface before ultrasonic information can be collected.

Because UT probes 1 and 2 have a diameter of 0.250 inch, these transducers should, in theory, be able to collect meaningful UT data down to a point approximately 0.125 inch (1/2 diameter) above the chamfer. However, based on prior UT inspection experience and a review of UT data from previous inspections, the circumferential-shooting TOFD transducer pair only collects meaningful data down to a point 0.200 inch above the chamfer. Below this point, UT data cannot be collected with transducers 1 and 2. To resolve the probe's blind zone limitation, new UT equipment would have to be developed and appropriately qualified.

In conclusion, CEDM nozzles can be inspected in accordance with the Order from 2 inches above the J-groove weld to a point approximately 1.544 inches above the bottom of the nozzle. Below this point, compliance to the Order would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

C. Suitability of Proposed Altemative The suitability of the proposed altemative was established by an engineering evaluation that includes a finite element stress analysis (FEA) and fracture mechanics evaluations. The intent of the engineering evaluation was to determine whether residual stresses in the bottom 1.544 inches of the ANO-2 CEDM nozzles were sufficient to cause an axial flaw to propagate to the nozzle J-groove weld region. As explained in Section IV.A above, the 1.544-inch dimension defines the UT examination lower limit with respect to the bottom of the CEDM nozzle. The axial flaw geometry was selected for evaluation because of its potential to propagate to the nozzle J-groove weld region.

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Four (4) CEDM nozzle locations were selected for analysis in the engineering evaluation. Selected locations were 00, 8.80, 28.80, and 49.60 with the 0° location at the vertical centerline of the RPV head, the 49.60 location being the outermost nozzles, and the other two being intermediate locations between the center and outermost locations. The selected nozzle locations provide an adequate representation of residual stress profiles and a proper basis for analysis to bound all nozzle locations.

Postulated flaw locations along the nozzle circumference were identified by an azimuth angle, zero degrees being the furthest point from the center of the RPV head (downhill side of nozzle). Hoop stress distributions for each of the selected nozzles were determined for flaws located at 00 and 900 because these locations represent the shortest distance that a flaw would have to propagate to reach the nozzle J-groove weld region.

The stress distributions in the selected CEDM nozzles were evaluated in the Ufree-span length" from the bottom of the nozzle to the face of the J-groove weld (at the projected cladding interface), exclusive of the fillet weld reinforcement. See Figure 3 for additional details. The free-span length used in the FEA was 2.70 inches.

However, based on ANO-2 design drawings, the minimum free-span length for the selected nozzles was determined to be 2.48 inches, which is 0.22 inch shorter than that the used in the FEA. To compensate for the longer free-span nozzle length of the FEA model, the location for determining the through-wall hoop stress distribution in the FEA was also adjusted to align the FEA location from which the residual stresses were determined with the design location of the UT examination lower limit.

To determine whether residual stresses at the UT examination lower limit were sufficient to cause an axial flaw to propagate to the nozzle J-groove weld region, partial-depth surface flaws on the inside and outside diameter surfaces and through-wall flaws were analyzed at the 00 and 900 azimuthal locations for each of the selected nozzles. Crack growth rates from EPRI Report MRP-55 were utilized.

Twenty-one (21) different flaw cases were analyzed with the following results:

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Nozzle Location Flaw Location on Axial Flaw Flaw Evaluation Results

• on RPV Head Nozzle (Azimuth) Evaluated 00 N/A ID Surface 13.12 years to reach J-weld OD Surface 20.90 years to reach J-weld Through-wall 3.52 years to reach J-weld 8.80 Downhill ID Surface 17.56 years to reach J-weld OD Surface 19.02 years to reach J-weld Through-wall 3.80 years to reach J-weld 900 ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall 9.72 years to reach J-weld 28.80 Downhill ID Surface No potential for flaw growth OD Surface 4.58 years to reach J-weld Through-wall 4.16 years to reach J-weld 900 ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall No potential for flaw growth 49.60 Downhill IDSurface No potential for flaw growth OD Surface 2.01 years to reach J-weld Through-wall 4.88 years to reach J-weld 900 ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall No potential for flaw growth

• - Indicating operating years In conclusion, the fracture mechanics evaluation demonstrated that residual stresses in the bottom 1.544 inches of the CEDM nozzle are insufficient to cause an axial flaw to propagate into the nozzle J-groove weld region prior to re-inspection during the next refueling outage. Based on the flaw evaluation, the shortest time for a flaw to grow from the UT examination lower limit to the nozzle J-groove weld region would be 2.01 years. Conservatism in the analysis (i.e.,

pressure applied to the flaw faces and high aspect ratio) provides additional assurance that an undetected flaw at the UT examination lower limit would not reach the nozzle J-groove weld region within one (1) operating cycle. Because stresses in CEDM nozzles below the UT examination lower limft are either lower than those at the limit or compressive, the potential for crack growth in this region is also significantly lower. For details regarding the engineering evaluation and its conclusions, see Engineering Report M-EP-2003-002, which is contained in of this submittal letter.

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Impracticalitv of Supplemental Liquid Penetrant (PT) or ECT Entergy also evaluated the feasibility of inspecting the bottom 1.544 inches of each CEDM nozzle using either the PT or ECT examination method. However, to perform a PT inspection, the guide cones would have to be removed from and reinstalled on all eighty-one (81) CEDM nozzles before and after performing the PT examinations. Entergy does not have the tooling to perform these operations remotely; therefore, the removaVreinstallation of the guide cones and the PT examinations would have to be performed manually. Manual performance of these operations would result in a significant increase in personnel radiation exposure.

Entergy estimates that the dose associated with performing this PT inspection to be approximately 3 REM per nozzle.

The feasibility of using ECT was also evaluated. However, as with the UT inspection, the bottom 1.344 inches could not be inspected due to the design of CEDM nozzle in the guide cone connection and chamfer region. Additionally, a small ECT blind zone would exist above this region, which would further reduce the effectiveness of ECT.

V. CONCLUSION Section IV.F of the Order states:

"Licensees proposing to deviate from the requirements of this Order shall seek relaxation of this Order pursuant to the procedure specified below. The Director, Office of Nuclear Reactor Regulation, may, in writing, relax or rescind any of the above conditions upon demonstration by the Licensee of good cause. A request for relaxation regarding inspection of specific nozzles shall also address the following criteria:

(1) The proposed alternative(s) for inspection of specific nozzles will provide an acceptable level of quality and safety, or (2) Compliance with this Order for specific nozzles would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety."

Entergy believes that compliance with the UT inspection provisions of Section IV.C.I.b(i) of the Order as described in Section II, above, would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The proposed alternative, described in Section III.B, would provide an acceptable level of quality and safety. The technical basis for the proposed alternative is documented in Engineering Report M-EP-2003-002, which is contained in Enclosure 3 of this submittal letter. Therefore, Entergy requests that the proposed altemative be authorized pursuant to Section IV.F of the Order.

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REACTOR -

PRE5SLRE VESSEL HEAD CONE OETAIL A' CEDM NOZZLE TYPICAL CEDM NOZZLE DETAIL W/ GUIDE CONE DETAIL DETAIL "A" FIGURE 1 TYPICAL CEDM NOZZLE DETAILS Page 8 of 10

CEDM Nozzle Blind Zone 0 0 Threaded Connection and Chamfer Region 0 0 UT Inspection Probe Schematic - See Table Below For Transducer Information Guide Cone Nozzle Position Mode Diameter Description 1 Transmit 0.25 inch Circumferential Scan Using TOFD 2 Receive 0.25 inch Circumferential Scan Using TOFD 3 Transmit 0.25 inch Axial Scan Using TOFD 4 Receive 0.25 inch Axial Scan Using TOFD 5 Transmit 0.25 inch Standard Zero Degree Scan Receive 6 Transmit 0.25 inch Standard Zero Degree Scan Receive 7 N/A 0.25 inch Eddy Current FIGURE 2 TYPICAL CEDM NOZZLE DETAILS Page 9 of 10

CEDM Nozzle J-Groove Weld RPV Head Inspectable Zone Analysis Crack Weld Length Growth Region (Shaded)

Uninspectable Zone r -.

CEDM /

Guide Cone FIGURE 3 DETAIL OF ANALYSIS CRACK GROWTH REGION Page 10 of 10

ENCLOSURE 2 CNRO-2003-00020 RELAXATION REQUEST FOR WATERFORD STEAM ELECTRIC STATION, UNIT 3

ENTERGY OPERATIONS, INC.

WATERFORD STEAM ELECTRIC STATION, UNIT 3 COMPONENT/EXAMINATION Component/Number: RC MRCT001

Description:

Reactor Pressure Vessel (RPV) Head Penetration Nozzles Code Class: 1

References:

1. NRC Order EA-03-009, Issuance of Order Establishing Interim Inspection Requirements for Reactor Pressure Vessel Heads at Pressurized Water Reactors

2. Letter W3F1-2003-0014 from Entergy Operations, Inc. to the NRC: Entergy Operations, Inc. - Answer to Issuance of Order Establishing Interim Inspection Requirements for Reactor Pressure Vessel Heads at Pressurized Water Reactors", dated February 28, 2003

3. Engineering Report M-EP-2003-002, Fracture Mechanics Analysis for Pimary Water Stress Corrosion Crack (PWSCC) Growth in the Un-Inspected Regions of the Control Element Drive Mechanism (CEDM) Nozzles at Arkansas Nuclear One Unit 2 & Waterford Steam Electric Station Unit 3

4. EPRI Material Reliability Program Crack Growth Rates for Evaluating Primary Water Stress Corrosion Cracking (PWSCC) of Thick-Wall Alloy 600 Materials (MRP-55)

Revision 1 Unit: Waterford Steam Electric Station, Unit 3 (Waterford 3)

Inspection Interval: Second (2nd) 10-Year Interval

11. REQUIREMENTS The NRC issued Order EA-03-009 (the Order) that modified the current licenses at nuclear facilities utilizing pressurized water reactors (PWRs), which includes Waterford Steam Electric Station, Unit 3 (Waterford 3). The NRC Order establishes inspection requirements for RPV head penetration nozzles. Waterford 3 is categorized as a High" PWSCC susceptibility plant based on an effective degradation year (EDY) greater than

12. According to Section IV.C.1(b) of the Order, RPV head penetration nozzles in the

'High' PWSCC susceptibility category shall be inspected using either of the following methods each refueling outage:

(i) Ultrasonic testing of each RPV head penetration nozzle (i.e. nozzle base material) from two (2) inches above the J-groove weld to the bottom of the nozzle and an assessment to determine if leakage has occurred into the interference fit zone.

Page 1 of 10

(ii) Eddy current testing or dye penetrant testing of the wetted surface of each J-groove weld and RPV head penetration nozzle base material to at least two (2) inches above the J-groove weld.

Ill. PROPOSED ALTERNATIVE A. Background The Waterford 3 RPV head has one hundred-two (102) penetration nozzles that include ninety-one (91) Control Element Drive Mechanism (CEDM) nozzles, ten (10) Incore Instrument (ICI) nozzles, and one (1) vent line nozzle. Nozzle dimensions are identified below.

RPV Penetration Nozzle Dimensions Nozzle Outside Dia. Inside Dia. Thickness CEDM 4.050 inches 2.728 inches 0.6610 inches ICI 5.563 inches 4.750 inches 0.4065 inches Vent Line 1.050 inches 0.742 inches 0.1540 inches Entergy Operations, Inc. (Entergy) plans to inspect RPV head penetration nozzles at Waterford 3 using the ultrasonic testing (UT) method in accordance with Section IV.C. 1(b)(i) of the Order. However, due to nozzle configuration at the guide cone connection and UT coverage limitations, CEDM nozzles cannot be inspected to the bottom as required by the Order. Therefore, Entergy requests relaxation from the UT coverage requirements of Section IV.C.1(b)(i) of the Order and proposes an altemative in Section III.B, below.

This relaxation request does not apply to ICI nozzles or the vent line nozzle.

B. Proposed Alternative Paragraph IV.C.1(b)(i) of the Order requires that the UT inspection of each RPV head penetration nozzle extend from two (2) inches above the J-groove weld to the bottom of the nozzle." Entergy requests relaxation from this provision for CEDM nozzles and proposes the following alternative:

• CEDM nozzles (i.e., nozzle base material) shall be ultrasonically examined from two (2) inches above the J-groove weld to 1.544 inches above the bottom of the nozzle. A fracture mechanics evaluation has been performed and demonstrates that residual stresses in the bottom portion of the nozzle are insufficient to cause an axial flaw to propagate into the pressure boundary region of the nozzle along the J-groove weld (nozzle J-groove weld region) prior to re-inspection during the next refueling outage.

Page 2 of 10

IV. BASIS FOR PROPOSED ALTERNATIVE A. Background UT inspection of CEDM nozzles will be performed using a combination of time-of-flight diffraction (TOFD) and standard 0 pulse-echo techniques. The TOFD approach utilizes two pairs of 0.250-inch diameter, 550 refracted-longitudinal wave transducers aimed at each other. One of the transducers sends sound into the inspection volume while the other receives the reflected and diffracted signals as they interact with the material. There will be one TOFD pair looking in the axial direction of the penetration nozzle tube and one TOFD pair looking in the circumferential direction of the tube. The TOFD technique is primarily used to detect and characterize planer-type defects within the full volume of the penetration tube.

The standard 0 pulse-echo ultrasonic approach utilizes two 0.250-inch diameter straight beam transducers. One transducer uses a center frequency of 2.25 MHz while the other uses a frequency of 5.0 MHz. The 0° technique is primarily used to plot the penetration tube outside diameter location and the J-groove attachment weld location, which are used to characterize orientation and size of the defect.

Additionally, the 0 technique is capable of locating and sizing any laminar-type defects that may be encountered.

The UT inspection procedures and techniques to be utilized at Waterford 3 have been satisfactorily demonstrated under the EPRI Materials Reliability Program (MRP) Inspection Demonstration Program.

B. Hardship and Unusual Difficulty Section VI.C.1(b)(i) of the Order requires UT inspection of RPV head penetration nozzles (i.e., nozzle base material) from two (2) inches above the J-groove weld to the bottom of the nozzle. However, a UT inspection of CEDM nozzles at Waterford 3 can only be performed from 2 inches above the J-groove weld down to a point approximately 1.544 inches above the bottom of the nozzle. The reduced coverage is due to CEDM nozzle configuration (1.344 inches) and inspection probe design limitations (0.200 inch) as described below.

• Nozzle Confiauration Limitation Guide cones (funnels) are attached to the bottoms of the Waterford 3 CEDM nozzles. The funnels are connected to the CEDM nozzles by threaded connections - the CEDM nozzles have intemal threads while the funnels have external threads. The length of the threaded connection region is 1.25 inches.

Additionally, a 450 chamfer exists immediately above the threaded connection region. The length of the chamfer region is 0.094 inch. (See Figure 1 for additional details.)

Due to the threaded connection and chamfer region at the bottom of each CEDM nozzle, a meaningful UT examination in that area cannot be performed.

The UT scans of the region are obscured by multiple signals reflected back by the threaded surfaces and chamfer. Therefore, UT of the bottom 1.344 inches of the CEDM nozzles is Impractical. To resolve UT limitations due to nozzle Page 3 of 10

configuration, the existing CEDM nozzle-to-funnel threaded connections would have to be eliminated, redesigned, and physically modified to provide for an acceptable UT examination.

• Inspection Probe Blind Zone The inspection probe to be used in the inspection of Waterford 3 CEDM nozzles consists of seven (7) individual transducers, as shown in Figure 2. Transducers 1 and 2 perform circumferential scans using TOFD; transducers 3 and 4 perform axial scans using TOFD; transducers 5 and 6 perform a standard 00 scan; and transducer 7 performs eddy current testing (ECT). (Note that the TOFD circumferential scans have demonstrated the capability to detect axial flaws in addition to circumferential flaws.) In order to achieve the maximum ultrasonic inspection coverage, the inspection probe is operated in such a way as to allow transducers 1 and 2 (UT TOFD for circumferential scans) to scan down to the top of the chamfer at the completion of the downward scan.

The inspection probe is designed so that the ultrasonic transducers are slightly recessed into the probe holder. This recess must be filled with water to provide coupling between the transducer and the component (i.e., nozzle wall).

Because of this design, the complete diameter of the transducer must fully contact the inspection surface before ultrasonic information can be collected.

Because UT probes I and 2 have a diameter of 0.250 inch, these transducers should, in theory, be able to collect meaningful UT data down to a point approximately 0.125 inch (1/2 diameter) above the chamfer. However, based on prior UT inspection experience and a review of UT data from previous inspections, the circumferential-shooting TOFD transducer pair only collects meaningful data down to a point 0.200 inch above the chamfer. Below this point, UT data cannot be collected with transducers 1 and 2. To resolve the probe's blind zone limitation, new UT equipment would have to be developed and appropriately qualified.

In conclusion, CEDM nozzles can be inspected in accordance with the Order from 2 inches above the J-groove weld to a point approximately 1.544 inches above the bottom of the nozzle. Below this point, compliance to the Order would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

C. Suitability of Proposed Alternative The suitability of the proposed alternative was established by an engineering evaluation that includes a finite element stress analysis (FEA) and fracture mechanics evaluations. The intent of the engineering evaluation was to determine whether residual stresses in the bottom 1.544 inches of the Waterford 3 CEDM nozzles were sufficient to cause an axial flaw to propagate to the nozzle J-groove weld region. As explained in Section IV.A above, the 1.544-inch dimension defines the UT examination lower limit with respect to the bottom of the CEDM nozzle. The axial flaw geometry was selected for evaluation because of its potential to propagate to the nozzle J-groove weld region.

Page 4 of 10

Four (4) CEDM nozzle locations were selected for analysis in the engineering evaluation. Selected locations were 00, 7.80, 29.10, and 49.70 with the 00 location at the vertical centerline of the RPV head, the 49.70 location being the outermost nozzles, and the other two being intermediate locations between the center and outermost locations. The selected nozzle locations provide an adequate representation of residual stress profiles and a proper basis for analysis to bound all nozzle locations.

Postulated flaw locations along the nozzle circumference were identified by an azimuth angle, zero degrees being the furthest point from the center of the RPV head (downhill side of nozzle). Hoop stress distributions for each of the selected nozzles were determined for flaws located at 00 and 900 because these locations represent the shortest distance that a flaw would have to propagate to reach the nozzle J-groove weld region.

The stress distributions in the selected CEDM nozzles were evaluated in the free-span length" from the bottom of the nozzle to the face of the J-groove weld (at the projected cladding interface), exclusive of the fillet weld reinforcement. See Figure 3 for additional details. The free-span length used in the FEA was 2.70 inches.

However, based on Waterford 3 design drawings, the minimum free-span length for the selected nozzles was determined to be 2.86 inches, which is 0.16 inch longer than that used in the FEA. As a result, the location of the UT examination lower limit in the FEA model is higher than the design location by 0.16 inch. Although the FEA location provides a higher through-wall hoop stress distribution, this location was used in the analysis for conservatism.

To determine whether residual stresses at the UT examination lower limit are sufficient to cause an axial flaw to propagate to the nozzle J-groove weld region, partial-depth surface flaws on the inside and outside diameter surfaces and through-wall flaws were analyzed at the 00 and 900 azimuthal locations for each of the selected nozzles. Crack growth rates from EPRI Report MRP-55 were utilized.

Twenty-one (21) different flaw cases were analyzed with the following results:

Page 5 of 10

Nozzle Location Flaw Location on Axial Flaw Flaw Evaluation Results*

on RPV Head Nozzle (Azimuth) Evaluated 00 N/A ID Surface 23.44 years to reach J-weld OD Surface No potential for flaw growth Through-wall 8.56 years to reach J-weld 7.80 Downhill ID Surface > 40 years to reach J-weld OD Surface No potential for flaw growth Through-wall 8.92 years to reach J-weld 900 ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall 35.52 years to reach J-weld 29.10 Downhill ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall 28.08 years to reach J-weld 90 ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall No potential for flaw growth 49.70 Downhill ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall No potential for flaw growth g0 ID Surface No potential for flaw growth OD Surface No potential for flaw growth Through-wall No potential for flaw growth

• - Indicating operating years In conclusion, the fracture mechanics evaluation demonstrated that residual stresses in the bottom 1.544 inches of the CEDM nozzle are insufficient to cause an axial flaw to propagate into the nozzle J-groove weld region prior to re-inspection during the next refueling outage. Based on the flaw evaluation, the shortest time for a flaw to grow from the UT examination lower limit to the nozzle J-groove weld region would be 8.56 years. Conservatism in the analysis (i.e.,

pressure applied to the flaw faces and high aspect ratio) provides additional assurance that an undetected flaw at the UT examination lower limit would not reach the J-groove weld interface within one (1) operating cycle. Because stresses in CEDM nozzles below the UT examination lower limit are either lower than those at the limit or compressive, the potential for crack growth in this region is also significantly lower. For details regarding the engineering evaluation and its conclusions, see Engineering Report M-EP-2003-002, which is contained in of this submittal letter.

Page 6 of 10

Impracticalitv of Suplemental Liquid Penetrant (PT) or ECT Entergy also evaluated the feasibility of inspecting the bottom 1.544 inches of each CEDM nozzle using either the PT or ECT examination method. However, to perform a PT inspection, the guide cones would have to be removed from and reinstalled on all ninety-one (91) CEDM nozzles before and after performing the PT examinations. Entergy does not have the tooling to perform these operations remotely; therefore, the removal/reinstallation of the guide cones and the PT examinations would have to be performed manually. Manual performance of these operations would result in a significant increase in personnel radiation exposure.

Entergy estimates that the dose associated with performing this PT inspection to be approximately 3 REM per nozzle.

The feasibility of using ECT was also evaluated. However, as with the UT inspection, the bottom 1.344 inches could not be inspected due to the design of CEDM nozzle in the guide cone connection and chamfer region. Additionally, a small ECT blind zone would exist above this region, which would further reduce the effectiveness of ECT.

V. CONCLUSION Section IV.F of the Order states:

'Licensees proposing to deviate from the requirements of this Order shall seek relaxation of this Order pursuant to the procedure specified below. The Director, Office of Nuclear Reactor Regulation, may, in writing, relax or rescind any of the above conditions upon demonstration by the Licensee of good cause. A request for relaxation regarding inspection of specific nozzles shall also address the following criteria:

(1) The proposed alternative(s) for inspection of specific nozzles will provide an acceptable level of quality and safety, or (2) Compliance with this Order for specific nozzles would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety."

Entergy believes that compliance with the UT inspection provisions of Section IV.C.1(b)(i) of the Order as described in Section II, above, would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The proposed alternative described in Section III.B of the request would provide an acceptable level of quality and safety. The technical basis for the proposed alternative is documented in Engineering Report M-EP-2003-002, which is contained in Enclosure 3 of this submittal letter. Therefore, Entergy requests that the proposed altemative be authorized pursuant to Section IV.F of the Order.

Page 7 of 10

NOZZLE REACTOR -

PRESSURE VESSEL HEAD UIDE CONE DETAIL A-CEDM NOZZLE TYPICAL CEDM NOZZLE DETAIL W/ GUIDE CONE DETAIL DETAIL "A" FIGURE 1 TYPICAL CEDM NOZZLE DETAILS Page 8 of 10

CEDM Nozzle

.I, Blind Zone 0 I I Threaded Connecton and Chamfer Region 0 0 UT Inspection Probe Schematic - See Table Below For Transducer Information Guide Cone Nozzle Position Mode Diameter Description I Transmit 0.25 inch Circumferential Scan Using TOFD 2 Receive 0.25 inch Circumferential Scan Using TOFD 3 Transmit 0.25 inch Axial Scan Using TOFD 4 Receive 0.25 inch Axial Scan Using TOFD 5 Transmit 0.25 inch Standard Zero Degree Scan Receive 6 Transmit 0.25 inch Standard Zero Degree Scan Receive 7 N/A 0.25 inch Eddy Current FIGURE 2 Inspection Probe Module Detail Page 9 of 10

CEDM Nozzle J-Groove Weld RPV Head Inspectable Zone Analysis Crack Weld Growth Region (Shaded)

Uninspectable Zone CEDM /

Guide Cone FIGURE 3 DETAIL OF ANALYSIS CRACK GROWTH REGION Page 10 of 10

ENCLOSURE 3 ENGINEERING REPORT M-EP-2003-002 FRACTURE MECHANICS ANALYSIS FOR THE ASSESSMENT OF THE POTENTIAL FOR PRIMARY WATER STRESS CORROSION CRACK (PWSCC)

GROWTH IN THE UNINSPECTED REGIONS OF THE CONTROL ELEMENT DRIVE MECHANISM (CEDM) NOZZLES AT ARKANSAS NUCLEAR ONE UNIT 2 &

WATERFORD STEAM ELECTRIC STATION UNIT 3

M-EP-2003-002 Engineering Report No. Rev. 00 Page I of 52

--- En(eg ENTERGY NUCLEAR SOUTH Engineering Report Coversheet Fracture Mechanics Analysis for the Assessment of the Potential for Primary Water Stress Corrosion Crack (PWSCC) Growth in the Un-Inspected Regions of the Control Element Drive Mechanism (CEDM) Nozzles at Arkansas Nuclear One Unit 2 & Waterford Steam Electric Station Unit 3 Engineering Report Type:

New X Revision 5l Deleted IEl Superceded .5 Applicable Site(s)

ANO X Echelon X GGNS El RBS O UTF3 X Report Origin: X ENS Safety-Related: X Yes El Vendor O No Vendor Document No.

Comments: Attached:

Prepared by:

1)-

1- r.4 I%ov-. *&x 4tW-k Date: 6 17/on0 DYes o Yes 4' w Responsipl Engineer 3 No 2 No Verified/ A C-2 R . Igi Reviewed by: Date: /b/o3gYes 2-Yes Design Verifier/jew KNo Approved by: Date: El Yes o Yes ResponsibleSupervisor or /tkNo , No Responsible Central Engineering Manager (for multiple site reports only)

Engineering Report -EP-2003-002 Rev. 00 Page 2aof 52 Engineering Report No. Rev.

Page of RECOMMENDATION FOR APPROVAL FORM Comments: Attached:

Date: E]Yes E Yes Prepared bv:

_4~ 9, yw/vyR C este (No No Concurrence. ttj Date: 6U-3 O)yes O Yes ReshsibleEngineering Manager, ANO UNo 1'No Not Applicable Concurrence: Date: O Yes O Yes Responsible Engineering Manager, GGNS O No No Not Applicable Concurrence: Date: _________ 0 Yes O Yes Responsible Engineering Manager, RBS No No Concurrence: See Page 2b for WF3 signature(s) Date: E Yes O Yes Responsible Engineering Manager, WF3 No No

Engineering Report M-EP-2003-002 Rev. 00 Page 2bof 52 Engineering Report No.

Page of RECOMMENDATION FOR APPROVAL FORM Comments: Aftached:

Date: a Yes El Yes Prepared by: See Page 2a for ANO signature(s)

Responsible Engineer a No Cl No Concurrence: Date: [I Yes El Yes Responsible Engineering Manager, ANO E No _l No Not Applicable Concurrence: Date: O Yes El Yes Responsible Engineering Manager, GGNS El No No Not Applicable Date: El Yes El Yes El No El No E Yes El Yes o-N  ;--

Engineering Report M-EP-2003-002 Rev. 00 Page 3 of 52 Table of Contents Section Title Page Number List of Tables 3 List of Figures 4 List of Appendices 7 1.0 Introduction 8 2.0 Stress Analysis 11 3.0 Fracture Mechanics Analysis 32 4.0 Discussion and Results 38 5.0 Conclusions 50 6.0 References 51 List of Tables Table Number Title Page Number IA ANO-2 CEDM Downhill Location Nodal Stresses 22 IB ANO-2 CEDM Ninety Degree Location Nodal 23 Stresses IIA WSES-3 CEDM Downhill Location Nodal Stresses 24 IIB WSES-3 CEDM Ninety Degree Location Nodal 25 Stresses III Hoop Stress Distribution Used for Analysis 26 (1.644' above Nozzle Bottom)

IV ANO-2 Evaluation Results 40 V WSES-3 Evaluation Results 41 VI Available Nozzle Length for (PWSCC) Flaw 42 Growth ViI ANO-2 Results for PWSCC Growth Cases 47 Vill WSES-3 Results for PWSCC Growth Cases 50

Engineering Report M-EP-2003-002 Rev. 00 Page 4 of 52 List of Figures Figure Title Page Number Number 1 Details of funnel connection to CEDM [21. Detail extracted from Drawing 9 M-2001-C2-107 [2]. The threaded region in the CEDM is 1.125 inch.

Both ANO-2 and WSES-3 have similar connection geometry 2 Sketch of the inspection probe [3a]. Both probes (EC and UT) have a 10 diameter 0.25 inch. The UT probes to detect axial flaws are numbered 1 and 2 and the EC probe is numbered 7.

3 ANO-2 CEDM Nozzles at four locations on the head. The region of 12 interest is located at the bottom. The cyan contour ranges fro 1Oksi (tensile) to zero; the light blue contour from zero to -10 ksi 9compressive and the dark blue contour is compressive stresses in excess of -10 ksi.

4 WSES-3 CEDM Nozzles at four locations on the head. The region of 13 interest is located at the bottom. The cyan contour ranges fro 1Oksi (tensile) to zero; the light blue contour from zero to -10 ksi 9compressive and the dark blue contour is compressive stresses in excess of -10 ksi.

5 ANO-2 Hoop stress profile (ID & OD) for the zero degree nozzle. 14 6 ANO-2 Hoop stress profile (ID & OD) for the "8.8" degree nozzle at the 15 downhill location.

7 ANO-2 Hoop stress profile (ID & OD) for the "28.8" degree nozzle at the 15 downhill location.

8 ANO-2 Hoop stress profile (ID & OD) for the "49.6" degree nozzle at the 16 downhill location.

9 ANO-2 Hoop stress profile (ID & OD) for the "8.8" degree nozzle at the 16 ninety degree location.

10 ANO-2 Hoop stress profile (ID & OD) for the "28.8 degree nozzle at the 17 ninety degree location.

11 ANO-2 Hoop stress profile (ID & OD) for the "49.6" degree nozzle at the 17 ninety degree location.

12 WSES-3 Hoop stress profile (ID & OD) for the zero' degree nozzle. 18 13 WSES-3 Hoop stress profile (ID & OD) for the "7.8" degree nozzle at the 19 downhill location.

14 WSES-3 Hoop stress profile (ID & OD) for the "29.1" degree nozzle at the 19 downhill location.

15 WSES-3 Hoop stress profile (ID & OD) for the "49.7" degree nozzle at the 20 downhill location.

16 WSES-3 Hoop stress profile (ID & OD) for the "7.8" degree nozzle at the 20 ninety degree location.

17 WSES-3 Hoop stress profile (ID & OD) for the "29.1" degree nozzle at the 21 ninety degree location.

18 WSES-3 Hoop stress profile (ID & OD) for the "49.7" degree nozzle at the 21 ninety degree location.

Engineering Report M-EP-2003-002 Rev. 00 Page 5 of 52 List of Figures (Continued)

Figure Title Page Number Number 19 ANO-2 downhill location for all nozzles evaluated. The stress distribution 27 is from the ID to OD. The coefficients in the respective equations will be used in the fracture mechanics analysis.

20 ANO-2 90° azimuth location for all nozzles evaluated. The stress 28 distribution is from the ID to OD. The coefficients in the respective equations will be used in the fracture mechanics analysis.

21 ANO-2 downhill location for all nozzles evaluated. The stress distribution 28 is from the OD to ID. The coefficients in the respective equations will be used in the fracture mechanics analysis.

22 ANO-2 900 azimuth location for all nozzles evaluated. The stress 29 distribution is from the OD to ID. The coefficients in the respective equations will be used in the fracture mechanics analysis.

23 WSES-3 downhill location for all nozzles evaluated. The stress 30 distribution is from the IDto OD. The coefficients in the respective equations will be used in the fracture mechanics analysis.

24 WSES-3 900 azimuth location for all nozzles evaluated. The stress 30 distribution is from the IDto OD. The coefficients in the respective equations will be used in the fracture mechanics analysis.

25 WSES-3 downhill location for all nozzles evaluated. The stress 31 distribution is from the OD to ID. The coefficients in the respective equations will be used in the fracture mechanics analysis.

26 WSES-3 900 azimuth location for all nozzles evaluated. The stress 31 distribution is from the OD to ID. The coefficients in the respective equations will be used in the fracture mechanics analysis.

27 Comparison of SIF from reference 8 and 9 utilizing the same 34 stress distribution (WSES-3, 7.80 nozzle at the 00 azimuth at an axial elevation of 1.644" above bottom of nozzle.

28 Curve fit equations for the "extension and bending" components 36 in reference 10. Table 1c and 1d for membrane loading and tables I g and I h for bending loading.

29 ANO-2; Plots for an ID surface crack growth and SIF versus 43 operating time for the 00 nozzle at the 00 azimuth (downhill position).

30 ANO-2; Plots for an ID surface crack growth and SIF versus 43 operating time for the 8.80 nozzle at the 00 azimuth (downhill position).

31 ANO-2; Plots for an OD surface crack growth and SIF versus 43 operating time for the 00 nozzle at the 00 azimuth (downhill position).

32 ANO-2; Plots for an OD surface crack growth and SIF versus 44 operating time for the 8.80 nozzle at the 00 azimuth (downhill position).

33 ANO-2; Plots for an OD surface crack growth and SIF versus 44 operating time for the 28.80 nozzle at the 00 azimuth (downhill position).

Engineering Report M-EP-2003-002 Rev. 00 Page 6 of 52 List of Figures (Continued)

Figure Title Page Number Number 34 ANO-2; Plots for an OD surface crack growth and SIF versus 44 operating time for the 49.60 nozzle at the 0" azimuth (downhill position).

35 ANO-2; Plots for a through-wall axial crack growth and SIF versus 45 operating time for the 0° nozzle at the 0° azimuth (downhill position).

36 ANO-2; Plots for a through-wall axial crack growth and SIF versus 45 operating time for the 8.80 nozzle at the 0" azimuth (downhill position).

37 ANO-2; Plots for a through-wall axial crack growth and SIF versus 45 operating time for the 28.8" nozzle at the 00 azimuth (downhill position).

38 ANO-2; Plots for a through-wall axial crack growth and SIF versus 46 operating time for the 49.60 nozzle at the 0" azimuth (downhill position).

39 ANO-2; Plots for a through-wall axial crack growth and SIF versus 46 operating time for the 8.8" nozzle at the 900 azimuth 40 WSES-3; Plots for an ID surface axial crack growth and SIF 47 versus operating time for the 00 nozzle at the 0° azimuth (downhill position).

41 WSES-3; Plots for an ID surface axial crack growth and SIF 48 versus operating time for the 7.80 nozzle at the 0° azimuth (downhill position).

42 WSES-3; Plots for a through-wall axial crack growth and SIF 48 versus operating time for the 00 nozzle at the 00 azimuth (downhill position).

43 WSES-3; Plots for a through-wall axial crack growth and SIF 48 versus operating time for the 7.80 nozzle at the 00 azimuth (downhill position).

44 WSES-3; Plots for a through-wall axial crack growth and SIF 49 versus operating time for the 29.1" nozzle at the 0" azimuth (downhill position).

45 WSES-3; Plots for a through-wall axial crack growth and SIF 49 versus operating time for the 7.80 nozzle at the 900 azimuth.

Engineering Report M-EP-2003-002 Rev. 00 Page 7 of 52 List of Appendices I Appendix Content of Appendix Number of Number Attachments In Appendix I Design Input Information- Concurrence from Site 4 II Mathcad worksheets for ANO-2 Analyses 21 III Mathcad worksheets for WSES-3 Analyses 21

Engineering Report M-EP-2003-002 Rev. 00 Page 8 of 52 1.0 Introduction The US Nuclear Rgulatory Commission (NRC) issued Oder EA-03-009 [1],

which modified licenses, requiring inspection of all Control Element Drive Mechanism (CEDM), In-Core Instrumentation (ICI), and vent penetration nozzles in the reactor vessel head. The region for inspection, specified in the Order paragraph IV.C.1.b, requires the inspection to cover a region from the bottom of the nozzle to two (2.0) inches above the J-groove weld. In the Combustion Engineering (CE) design the CEDM nozzles have a funnel affached to the bottom of each CEDM. Figure 1 [2]

provides a drawing showing the attachment detail and a sketch showing the typical CEDM arrangement in the reactor vessel head. The attachment is a threaded connection with a securing set-screw between the funnel and the CEDM nozzle. The CEDM nozzle is internally threaded and the funnel has extemal threads. Thus, the CEDM nozzles in the region of attachment, including the chamfered region, become in-accessible for both Eddy Current (EC) and Ultrasonic Testing (UT) to interrogate the nozzle base metal in this region. The design of the EC probe would have a small dead zone above the chamfer region whereas the design of the UT probes would have a larger region above the chamfer (0.200 inch [reference 3a &3b]) that cannot be inspected. Therefore, the region of the CEDM base metal that can be inspected extends from about 1.544 inches (UT) above the bottom of the CEDM nozzle to two (2.0) inches above the J-groove weld. The unexamined length constitutes the threaded region, the chamfer region, and the UT dead zone (1.250 + 0.094 + 0.200).

Therefore, the examination region would be the difference between the freespan length of the nozzle below the J-weld and the un-examinable region. The freespan length for both Arkansas Nuclear One, Unit 2 (ANO-2) and Waterford Steam Electric Station, Unit 3 (WSES-3) were determined by a detailed review of applicable design drawings and are provided as an attachment in Appendix I. The freespan lengths were compared to the freespan length used in the finite element based residual stress analysis to ascertain the location for the determination of throughwall stress distribution. This aspect is discussed in more detail in Section 2.

In order to exclude the inaccessible region from the inspection campaign, a relaxation of the Order is required pursuant to the requirements prescribed in Section IV.F and footnote 2 of the order [1]. This relaxation request must demonstrate that not examining the full extent of the nozzle tube below the J-weld will not negatively impact the level of quality and safety.

The purpose of this engineering report is to document the analyses performed for ANO-2 and WSES-3 to assess the propensity for primary water stress corrosion cracking (PWSCC) based on postulated flaws existing in the un-inspectable region.

The results of the various analyses performed demonstrate that not inspecting the inaccessible region will not negatively impact the level of quality and safety.

Engineering Report M-EP-2003-002 Rev. 00 Page 9 of 52 DETAIL "A" CEOM NOZZLE DETAIL TYPICAL CEOMNOZZLE W/ GUIDE CONE OErAIL a b C Figure 1: a)CEDM Nozzle tube.

b) Details of the chamfer in the machined recess of the threaded region. Provides dimensions for the threaded and chamfer regions.

C) Details of funnel connection to CEDM 2J.

d) Sketch of a typical CEDM penetration showing the region of interest The freespan of the CEDM labeled L' is the nozzle extension below the J-weld and is the freespan length.

Detail extracted from Drawing M-2001-C2-23 (ANO-2) & 1564-506 (WSES-3) 12). The threaded region in the CEDM is 1.344 inches (Threads plus Recess plus chamfer). Both ANO-2 and WSES-3 have similar connection geometry.

d The detail of the funnel-to-CEDM connection shows that the threaded +

chamfer region is 1.344 inches in height. The UT dead zone, determined to be 0.200 inch above the top of the threaded region in the CEDM, is based on the inspection probe design [3b], (shown in Figure 2).

Engineering Report M-EP-2003-002 Rev. 00 Page 10 of 52 CEDM Nozzle-T 0.200' Blind 0 Q I

Threaded Connection and Chamfer Region 0 0D UT Inspection Probe Schematic - See Table Below For Transducer Infornation Guide -

Cone k1._,_

Position Mode [Diameter Description T Transmit 0.25" Circumferential Scan Using TOFD 2 0.~Receive 5 Circumferential Scan Using TOFD 3 Transmit 0.25" Axial Scan Using TOFD 4 Receive 0.25" Axial Scan Using TOFD fi Transmit 5 Standard Zero Degree Scan Receive 6 Transmit 0.25" Standard Zero Degree Scan Receive Figure 2: Sketch of the inspection probe 13aJ. Probe 7 is a Eddy Current (EC) probe.

Based on the probe design and the geometry of the nozzle at the threaded connection, the explanation provided in Reference 3b shows the dead zone to extend 0.200 inch above the chamfer region immediately above the threads. Therefore, to account for the thread region, chamfer and the NDE dead zone, the un-inspected height is determined to be 1.544 inch (1.250" + 0.094"+0.2") above the bottom of the nozzle. Thus, the stresses in the region of interest are 1.544 inches above the bottom of the nozzle tube. The hoop stress at this location will be utilized to evaluate the PWSCC growth potential given an assumed axial part through-wall surface flaw equal

Engineering Report M-EP-2003-002 Rev. 00 Page 11 of 52 to the smallest flaw successfully detected by UT. The details of the geometrical input, stress analysis, and crack growth rate utilized for the analyses presented in this report are provided in Appendix I. The initial flaw size is obtained from Reference 4 (ID axial flaw is 0.035 inch deep; OD axial flaw is 0.0665 inch deep). The flaw length is estimated based on an aspect ratio of ten (10) such that the stress intensity factors (SIF) are conservatively maximized for the given depth. In addition, a through-wall axial flaw having a length of 0.5 inch is evaluated to ensure completeness of the assessment. The axially oriented flaws at this location have the potential for propagation towards the attachment weld. Therefore, axial flaws are postulated for the fracture mechanics based analysis.

The analyses performed include a finite element stress analysis of the CEDM nozzles and fracture mechanics based crack growth analysis for PWSCC. These analyses were performed for four nozzles in each reactor vessel head (ANO-2 and WSES-3) to account for the varied geometry of the nozzle penetration. The sections that follow contain a description of the analyses, the results, and conclusions supported by the analyses.

2.0 Stress Analysis Finite element based stress analysis for the ANO-2 and WSES-3 CEDM and ICI nozzle penetrations, using the highest tensile yield strength for each group of nozzles in each plant, were performed in February 2002 to ensure that sufficient information existed to perform fracture mechanics analyses in the event flaws were, discovered during the inspection campaign of 2002. Four nozzle locations that spanned the CEDM penetrations were selected for analyses. The locations were selected to provide an adequate representation of residual stress distribution and, hence, facilitate proper analyses. The yield strength values used are presented in tables IA, IB, IIA, and IIB with the hoop stress values. These analyses were performed to assess the stress profiles using both the welding induced residual and the operating stresses in the nozzle and the J-groove welds. The analysis for ANO-2 is documented in Reference 5a and for WSES 3 in Reference 5b.

Four CEDM nozzles representing the various hillside angle were selected for analyses described in this report. The stress contours for ANO-2 [5a] CEDM nozzles are presented in Figure 3 and for WSES-3 [5b] in Figure 4. The hoop stress plots for the ANO-2 CEDMs show that the stresses in the region of interest, the bottom part of the nozzle, range from a very low tensile value to predominantly compressive stress.

The nozzle extension below the J-groove weld on the downhill side is shorter than on the uphill side, indicating that a flaw in the uphill region would have to propagate a longer distance. Therefore, the region of interest for analysis is the downhill and an azimuthal plane ninety degree rotated from the downhill location.

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The cyan contour ranges from 10 ksi (tensile) to 0 ksi; the light blue contour from 0 ksi to -10 ksi (compressive) and the dark blue contour indicate compressive stresses in excess of -10 ksi.

The CEDM at zero degree (00) is axi-symmetric and the contours show the symmetric behavior. The other CEDM nozzles at higher penetration angles begin to show asymmetry. The CEDM at 8.80 shows the compressive stress and the low stress regions in the bottom of the nozzle in the region of interest. The distribution is skewed towards the downhill side of the nozzle. The distance from the bottom of the CEDM to the attachment J-weld on the downhill side is shorter than on the uphill side.

In addition, the stress distribution change on the downhill side occurs over a shorter nozzle length. At ninety degrees from the downhill side the distribution appears to be between the downhill and uphill side distributions. At these higher hillside angles the stress profiles at both the downhill and at the ninety degree locations were evaluated.

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Engineering Report M-EP-2003-002 Rev. 00 Page 13 of 52 The nozzles at higher penetration angles show the asymmetric distribution to a higher degree. Therefore, for these nozzles both locations were evaluated.

The stress contours for the WSES-3 CEDMs are presented in Figure 4 below.

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• s l IIIIl Il f.t3cEDE 29 ld s9k*4 es/2 728*2 ss-O2B): Operatt66 "29.1 " Degree CEDM Figure 4: WSES-3 CEDM Nozzle at four locations on the head. The region of interest is located at the bottom.

The cyan contour ranges from 0ksi (tensile) to 0 ksi; the light blue contour from 0 ksi to -10 ksi (compressive) and the dark blue contour indicates compressive stresses in excess of -10 ksi.

The stress contours for WSES-3 are similar to those for ANO-2, presented in Figure 3. Therefore, the locations for the evaluations are also similar. The hoop stress distribution along the nozzle height from the bottom of the nozzle to the bottom of the J-weld was plotted for both units at the two regions of interest (downhill and the ninety degree plane). Figures 5 through 11 present the information for ANO-2 and Figures 12 through 18 present the information for WSES-3. In these figures, the hoop stress for both the ID and OD surfaces are plotted and the lower inspection limit is shown for reference.

Engineering Report M-EP-2003-002 Rev. 00 Page 14 of 52 The CEDM nozzle lengths for the ANO-2 nozzles were determined (Appendix I, Attachment 4) and the minimum freespan length was found to be 2.48 inches.

However, the freespan length used in the finite element residual stress analysis was 2.70 inches. Therefore, the actual nozzle is 0.22 inch shorter than that used in the residual stress analysis. The stresses at the end of the nozzle are compressive and hence the use of a shorter length in the finite element analysis is inconsequential. To account for the shorter design length of the nozzle, the location where the through-wall residual stress would be estimated was determined as the sum of the un-inspectable length (1.544 inch) plus the difference in the nozzle length (0.22 inch).

Thus, the location for determining the through-wall hoop stress distribution was established to be 1.764 inches. This location is shown on Figures 5 through 11 as a red line labeled "Analysis Elevation". The nozzle bottom is shown in blue.

ANO-2 "O" Degree CEDM - Downhill 60 --- ID Distribution OD distribution 40~ ~ -<1.544 j inches 40 to ~ Nozzle Bottom Analysis Elevation 0

0.

0 0

0 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Bottom of Nozzle inch)

Figure 5: ANO-2 hoop stress profile (ID & OD) for the zero degree nozzle. This nozzle is symmetric about its central axis, hence this distribution would exist at all azimuthal locations.

Engineering Report M-EP-2003-002 Rev. 00 Page 15 of 52 ANO-2 "8.8" Degree CEDM - Downhill 60 40 0

2 20 0

0 0

I 0

-2 0 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Bottom {inch}

Figure 6: ANO-2 hoop stress profile (ID & OD) for the 8.8" degree nozzle at the downhill location.

ANO-2 "28.8" Degree CEDM - Downhill 80 60 0

v 40 8 20 I

0

-20 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Bottom {inch}

Figure 7: ANO-2 hoop sttess proflle (ID & OD) for the 28.8" degree nozzle at the downhill location.

C- oLf

Engineering Report M-EP-2003-002 Rev. 00 Page 16 of 52 ANO-2 "49.6" Degree CEDM - Downhill 80 -

No 1.544 inches tn 4 0 - Analysis Elevation t

2 cjvt 0.

Nozzle Bottom 0

0 I

0-0 Distribution O1D distribution

-40 0.0 0.5 1.0 1.5 2.0 Axial Distance from Nozzle Bottom {inch}

Figure 8: ANO-2 hoop stress profile (ID & OD) for the "49.6" degree nozzle at the downhill location.

ANO-2 "8.8" Degree CEDM -"90" Deg. Plane 60 40 CO

'a 2

'n 20 0

0 I

0

-20 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Bottom {inch}

Figure 9: ANO-2 hoop stress profile (ID & OD) for the 8.8" degree nozzle at the ninety degree location.

Engineering Report M-EP-2003-002 Rev. 00 Page 17 of 52 ANO-2 "28.8" Degree CEDM - "90" Deg. Plane 50

'a!t 30 o

0 0

I 10

-1 0 0.0 0.5 1.0 ' 1.5 2.0 2.5 3.0 3.5 Axial Distance from Nozzle Bottom {inch}

Figure 10: ANO-2 hoop stress profile (ID & OD) for the "28.8" degree nozzle at the ninety degree location.

ANO-2 "49.6" Degree CEDM -"90" Deg. Plane 40 -_ . 1.544 inches 30 -

. 2Analysi EID Dstton I D Distribution l

-2 0 0 1 2 3 4 Axial distance from Nozzle Bottom inch}

Figure 11: ANO-2 hoop stress profile (ID & OD) for the 49.6 degree nozzle at the ninety degree location.

The CEDM nozzle lengths for the WSES-3 nozzles were determined (Appendix 1,Attachment 4) and the minimum freespan length was found to be 2.86 inches.

However, the freespan length used in the finite element residual stress analysis was

Engineering Report M-EP-2003-002 Rev. 00 Page 18 of 52 2.70 inches; therefore, the actual nozzle is 0.16 inch longer than that used in the residual stress analysis. The analysis location was measured at 1.544 inches from the finite element analysis model nozzle bottom. As a result the analysis location is actually higher than the lower limit of the inspection zone. This provides a conservatively higher hoop stress distribution at the analysis location. Thus, the location for determining the through-wall hoop stress distribution was established at 1.544 inches. This location is shown on Figures 12 through 18 as a red line labeled "Analysis Elevation". The nozzle bottom is shown in blue and the measurement for the analysis location is from the green line (finite element model nozzle bottom).

WSES-3 "O"Degree CEDM - Downhill 100 60 40 r:-

ci, CD 0

0 I° 0

-20 1

0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Botom {inch}

Figure 12: WSES-3 hoop stress profile (ID & OD) for the "zero' degree nozzle. This nozzle is symmetric about its central axis, hence this distribution would exist at all azimuthal locations.

~------

---~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

---

~~~

~~~~~~~~

6-07

Engineering Report M-EP-2003-002 Rev. 00 Page 19 of 52 WSES-3 "7.8" Degree CEDM - Downhill 60 40 ea 2

00 2 0 I

0

-20 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Bottom (inch)

Figure 13: WSES-3 hoop stress profile (ID & OD) for the "7.8" degree nozzle at the downhill location.

WSES-3 "29.1" Degree CEDM - Downhill 80 60 40 U2

0. 40 0

MO 20 0

-20 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Bottom {inch}

Figure 14: WSES-3 hoop stress profile (ID & OD) for the "29.1" degree nozzle at the downhill location.

! - 6e)

Engineering Report M-EP-2003-002 Rev. 00 Page 20 of 52 WSES-3 "49.7" Degree CEDM - Downhill 90 a!.60

'n 0

C5 0

0 o0 0.0 0.5 1.0 1.5 2.0 2.5 Axial Distance from Nozzle Bottom {inch)

Figure 15: WSES-3 hoop stress profile (ID & OD) for the "49.7 degree nozzle at the downhill location.

WSES-3 "7.8" Degree CEDM - "90" Degree Plane 60 40 m

0) 0 20 0

I 0

-2 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Axial Distance from Nozzle Bottom {inch}

Figure 16: WSES-3 hoop stress profile (ID & OD) for the 7.8" degree nozzle at the ninety degree location.

Engineering Report M-EP-2003-002 Rev. 00 Page 21 of 52 WSES-3 "29.1" Degree CEDM - "90" Degree Plane 50 0 30 I

10

-1 0 0 1 2 3 4 Axial Distance from Nozzle Bottom {inch}

Figure 17: WSES-3 hoop stress profile (ID & OD) for the "29.1 degree nozzle at the ninety degree location.

WSES-3 "49.7" Degree CEDM - "90" degree Plane 50 30

'u4 n 10 U1)C 8

I -10

-30

-50 0 1 2 3 4 5 Axial Distance from Nozzle Bottom {inch}

Figure 18: WSES-3 hoop stress profile (ID & OD) for the "49.7 degree nozzle at the ninety degree location.

c -/O

Engineering Report M-EP-2003-002 Rev. 00 Page 22 of 52 The nodal stresses at each location within the region of interest, including the CEDM nozzle through-wall distribution, were obtained. The data for ANO-2 [5a] are presented in Table IA (downhill) and IB (ninety degree).

Table IA: ANO-2 CEDM Downhill Location Nodal Stresses 0 Dogree CEDM: Nozzle Yield Strength 42.5 ksl Through-wall Hoop Stress (ksi) at Axial Elevation above Nozzle Bottom (inch)

(% l 0.000" 0.648" 1.167" 1.682" 1.915" 2.182" ID -18.174 -3.378 17.707 27.601 35.706 36.728 25 -16.566 -4.971 13.472 24.308 30.013 30.156 50 -15.827 -6.589 8.529 18.751 24.861 27.991 75 -15.241 -8.046 4.002 13.672 21.360 33.445 OD -14.746 -9.230 -0.022 5.239 18.031 41.952 8.8 Degree CEDM: Nozzle Yield Strength 42.5 ksi Through-wall Hoop Stress (ksl) at Axial Elevatlon above Nozzle Bottom (Inch)

(%) 0.000" 0.649" 1.168" 1.584" 1.918"1 2.185" ID -13.903 -3.845 14.107 24.745 33.654 34.984 25 -12.842 -4.967 9.739 19.809 27.773 29.025 50 -12.437 -6.115 5.959 15.965 23.761 27.507 75 -12.104 -7.186 2.702 12.974 20.928 32.595 OD -11.845 -8.071 0.107 6.544 17.580 41.361 28.6 Degree CEDM: Nozzle Yield Strength 56.0 ksl Through-wall Hoop Stress (ksl) at Axil Elevation above Nozzle Bottom (inch)

M_) 0.000" 0.623" 1.121" l 1.521" 1.841" l 2.097 ID -15.079 -7.353 3.146 17.682 21.792 28.594 25 -12.024 -6.067 1.976 15.261 23.215 31.061 50 -10.260 -5.324 1.019 14.009 23.236 32.744 75 -8.553 -4.750 0.316 11.128 24.993 38.493 OD -6.900 -4.182 -OA86 7.402 21.289 49.119 49.6 Degree CEDM: Nozzle Yield Strength 42.5 ksi Through-wall Hoop Stress (ksi) at Axial Elevation above Nozzle Bottom (Inch)

(%) 0.000" 0.551" 0.994" 1.348" 1.632" 1.859" ID -25.184 -15.541 -4.320 -2.348 0.394 5.222 25 -17.168 -9.772 -1.460 1.854 6.302 15.202 50 -11.981 -5.649 0.195 6.109 11.947 27.448 75 -7.221 -2.000 2.671 8.699 16.295 37.283 OD -2.522 1.254 4.723 7.663 12.200 43.599

Engineering Report M-EP-2003-002 Rev. 00 Page 23 of 52 Table IB: ANO-2 CEDM Ninety Degree Location Nodal Stresses 8.8 Degree CEDM: Nozzle Yield Strength 42.5 ksi Through-wall Hoop Stress (ksl) at Axial Elevation above Nozzle Bottom (Inch)

(%) 0.000 0.730" 1.314" 1.783" 2.158" ID -10.731 -4.281 12.692 24.989 34.068 25 10.112 -5.586 8.192 20.902 28.570 50 -10.106 -6.943 3.707 15.434 23.531 75 -10.114 -8.196 -0.094 10.477 19.021 OD -10.115 -9.191 -3.033 2.675 14.013 28.8 Degree CEDM: Nozzle Yield Strength 56.0 ksl Throughwall Hoop Stress (ksi) at Axial Elevation above Nozzle Bottom (Inch)

(%) 0.000" 0.921" 1.658" 2.248" 2.722" ID 2.507 -0.870 6.063 23.514 30.524 25 -0.271 -3.316 1.576 17.081 24.882 S0 -2.420 -5.308 -1.711 12.746 21.125 75 4.253 -7.142 -3.799 8.482 18.233 OD 6.128 -8.711 -4.940 4.216 14.638 49.6 Degree CEDM: Nozzle Yield strength 42.5 ksl Through-wall Hoop Stress (ksi) at Axial Elevation above Nozzle Bottom (Inch)

%) 0.000" l 1.202" 2.165" 2.937" 3.555" ID 13.205 6.283 11.399 15.862 9.889 25 5.620 0.693 4.622 10.927 7.302 50 0.451 -3.364 2.033 7.467 7.076 75 4.177 -6.778 -0.817 3.172 7.085 OD -8.970 -9.281 -3.788 -0.814 6.674 The nodal stresses at each location within the region of interest, including the CEDM nozzle through-wall distribution, were obtained. The data for WSES-3 [5b] are presented in Table IIA (downhill) and IIB (ninety degree).

Engineering Report M-EP-2003-002 Rev. 00 Page 24 of 52 Table IIA: WSES-3 CEDM Downhill Location Nodal Stresses 0 Degree CEDM: Nozzle Yield Strength 52.5 ksi Through-wall Hoop Stress (ksl) at Axial Elevation above Nozzle Bottom (inch)

(h) 0.000" 0.696" 1.253" 1.699" 2.057" ID -14.500 -4.490 16.567 33.118 41.880 25 -13.368 -5.979 10.041 30.631 35.593 50 -13.089 -7.512 3.380 24.076 29.972 75 -12.849 -8.946 -0.004 16.650 26.244 OD -12.575 -10.116 -2.125 7.590 21.339 7.8 De gree CEDM: Nozzle Yield Strength 5 .5 ksl Through-wall Hoop Stress (ksl) at Axial Elevation above Nozzle Bottom (inch)

(%) 0.000" 0.692" 1.246" 1.69" l 2.045" ID -11.488 4.984 9.838 33.456 40.203 25 -10.750 -5.963 5.152 26.212 33.889 50 -10.612 -7.074 1.606 20.615 29.000 75 -10.497 -8.133 -0.676 15.121 25.574 OD -10.364 -8.997 -2.072 8.298 20.134 29.1 Degree CEDM: Nozzle Yield Strength 69.0 ksl Through-wall Hoop Stress ksl) at Axial Elevation above Nozzle Bottom (nch)

(%) 0.000" 0.716" 1.29" 1.749" 2.117" ID -12.397 -8.061 1.677 22.321 34.745 25 -9.637 -7.005 -0.108 17.800 32.422 50 -8.301 -6.463 -1.732 13.249 30.144 75 -6.813 -6.130 -2.813 9.424 27.897 OD -5.430 -5.664 4.077 7.569 23.028 49.7 Degree CEDM: Nozzle Yield Strength 59.0 ksi Through-wall Hoop Stress (ksi) at AxIal Elevation above Nozzle Bottom (inch)

(%) 0.000" 0.675" l 1.216" 1.649" 1.997" ID -22.205 -15.824 -7.096 5.740 21.020 25 -14.637 -10.492 4.329 6.370 22.571 50 -10.002 -6.695 -2.708 7.491 22.166 75 -5.449 -3.499 -0.646 8.396 22.359 OD -1.196 -0.489 0.843 9.419 17.193

Engineering Report M-EP-2003-002 Rev. 00 Page 25 of 52 Table IIB: WSES-3 CEDM Ninety Degree Location Nodal Stresses 7.8 Degree CEDM: Nozzle Yield Strength 52.5 ksl Through-wall Hoop Stress ksl) at Axial Elevation above Nozzle Bottom (inch)

( 0.000 " 0.777" 1.4" 1.898" l ID -8.232 -5.188 11.329 30.559 25 -7.953 -6.473 5.581 27.114 50 -8.301 -7.828 -0.398 20.483 75 -8.554 -9.125 -3.343 13.027 OD -8.717 -10.159 -5.068 4.659 29.1 Degree CEDM: Nozzle yield strength 59.0 ksl Through-wall Hoop Stress (ksl) at Axial Elevation above Nozzle Bottom (Inch)

(%) 0.000" l 1.039" 1.871" l 2.538" ID 5.028 -2.506 3.494 26.467 25 2.012 -4.591 -0.645 19.804 50 -0.454 -6.325 -4.005 14.930 75 -2.381 -8.016 -5.897 9.303 OD -4.504 -9.380 -7.383 3.556 49.7 Degree CEDM: Nozzle Yield Strength 59.0 ksi Through-wall Hoop Stress (ksl) at Axial Elevation above Nozzle Bottom (inch)

(%/0) 0.000" l 1.365" 2.459" 3.335" ID 15.024 4.876 11.553 19.564 25 7.228 -0.670 4.623 15.107 50 1.713 -4.692 0.302 11.645 75 -3.023 -8.447 -1.890 6.550 OD -8.086 -11.634 -3.866 2.396 The hoop stress at the location selected for evaluation of the potential for PWSCC crack growth was obtained by linear interpolation between two axial nodal positions at each through-wall location. The axial heights above the nozzle bottom based on the earlier discussions were 1.764 inches above the nozzle bottom for ANO-2 and 1.544 inches above the nozzle bottom for WSES-3.

Table IlIl provides the hoop stress data at the location for the two nozzle orientations (downhill and ninety degree). The zero degree CEDM penetration has a hoop stress distribution that is axi-symmetric; hence, no separate ninety degree location data is needed for this orientation.

Engineering Report M-EP-2003-002 Rev. 00 Page 26 of 52 Table Ill: Hoop Stress Distribution Used for Analysis

{ANO-2: 1.764"; WSES-3: 1.544" above Nozzle Bottom)

Through-wall ANO-2 "0" Degree Nozzle WSES-3 "0" Degree Nozzle

(%) Downhill 90 Azimuth Down Hill 900 Azimuth Hoop Stress (ksl) Hoop Stress (ksl) Hoop Stress (ksi) Hoop Stress (ksl)

ID 32.0308 Values are the same 27.366. Values are the same as for the downhill as for the downhill 25 27.426 location because the 23.475 location because the 50 21.992 nozzle has a 16.883 nozzle has a symmetic geometry. symmetic geometry.

75 17.8738 10.862 OD 12.2304 4.214 Through-wall ANO-2 "8.8" Degree Nozzle WSES-3 "7.8" Degree Nozzle

(%) Downhill 900 Azimuth Downhill 900 Azimuth Hoop Stress (ksl) Hoop Stress (ksi) Hoop Stress (ksi) Hoop Stress (csl)

ID 29.5463 24.491 25.69 16.889 25 24.101 20.387 19.287 11.807 50 20.1664 14.959 14.364 5.639 75 17.2606 10.049 9.926 1.39 OD 12.4915 2.444 4.888 -2.255 Through-wall ANO-2 "28.8" Degree Nozzle WSES3 "29.1" Degree Nozzle

(%) Downhill 900Azimuth Downhill 900 Azimuth Hoop Stress (ksl) Hoop Stress (ksi) Hoop Stress (ksl) Hoop Stress (ksi)

ID 20.803 9.198 13.101 1.136 25 21.3011 4.362 9.802 -2.196 50 21.0158 0.886 6.558 4.917 75 21.6567 -1.593 3.959 -6.73 OD 17.9474 -3.295 2.368 -8.168 Through-wall AN0-2 "49.6" Degree Nozzle WSES-3 "49.7" Degree Nozzle

(%) Downhill 900 Azimuth Downhill 90° Azimuth Hoop Stress (ksi) Hoop Stress (ksl) Hoop Stress (ksl) Hoop Stress (ksl)

ID 3.2015 9.269 2.627 5.968 25 11.4773 2.986 3.776 0.137 50 20.9608 -0.214 5.018 -3.875 75 28.4995 -3.299 6.203 -7.374 OD 30.4584 -6.075 7.135 -10.363 The hoop stress data tabulated in Table I were curve fit with a third order polynomial to obtain the stress coefficients that would be used in the fracture

Engineering Report M-EP-2003-002 Rev. 00 Page 27 of 52 mechanics evaluation for the ID and OD part through-wall surface flaws. The curve fit and the curve fit equation were obtained using Axxum software [6]. The stress coefficients are multiplied by the shape coefficients to obtain the influence coefficients for determining the SIF. The method for determining the SIF using influence coefficients is provided in the following section.

Figures 19 through 22 present the through-wall hoop stress distributions for the ANO-2 nozzles at the locations shown in Table ll. The equations, with coefficients, provided in the table are annotated to show the nozzle location. The nozzle location is in front of the equation and an arrow indicates the respective curve. For the zero degree nozzle, at the ninety degree azimuth location, no curve is provided since the nozzle at this location is symmetric about its axis.

ANO-2 Hoop Stress Distribution "O"Degree Azimuth for ID Surface Flaws Axial Elevation 1.764 inches above Nozzle Bottom 2 3 Deg. = 32.1020 - 20.7862'x +4.6978*x - 3.7120'x 30 -

0 20-0 a) 0 I

10 -

3

'49.8' Deg = 3.2084 +25.8182*x +37.6387'x2 - 36.2000*x 0-0.1 0.3 0.5 0.7 0.9 1.1 Radial Distance from ID to OD {fraction}

Figure 19: ANO-2 downhill location for all nozzles evaluated. The stress distribution is from the ID to OD. The coefficients in the respective equations will be used in the fracture mechanics analysis.

c- l/

Engineering Report M-EP-2003-002 Rev. 00 Page 28 of 52 ANO-2 Hoop Stress Distribution "90" Degree Azimuth for ID Surface Flaws Axial Elevation 1.764 inches above Nozzle Bottom 20 -

'e 10 -

0 0

I 0-

= 9.2238 - 30.888s8 30.3394'x - 14.7947..3

-10 -Figure 9O azimuth location for all nozzles evaluated. The stress distribution is from the ID to OD.

ANO-220:

0.1 0.3 0.5 0.7 0.9 1.1 Radial Distance ID to OD {fraction}

Figure 2: ANO-2 90°'azimuth location for all nozzles evaluated. The stress distribution is from theID to OD.

The coefficients in the respective equations will be used in the fracture mechanics analysis.

AN 0-2 Hoop Stress Distribution "0" Degree Azim uth for OD Surface Flaws Axial Elevation 1.764 inches above N ozzle Bottom

..4 6" 0kg = 30 4653 7 5044'x - 70 961 3'2 36 2000*x3 30 -

20 0

I 10 -

4 V Dag = 12.3016 22 5266'x 6 382 '

• 37120'x3 0 - _ I , . .~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

0.1 0 3 0.5 0.7 0.9 1 .1 R adial D istance from O D to ID {fraction}

Figure 21: ANO-2 downhill location for a/ nozzles evaluated. The stress distribution is from the OD to ID. The--

coefficients in the respective equations will be used in the fracture mechanics analysis.

(-j~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Engineering Report M-EP-2003-002 Rev. 00 Page 29 of 52 ANO-2 Hoop Stress Distribution "90" Degree Azimuth for OD Surface Flaws Axial elevation 1.764 inches above Nozzle Bottom 2 3 "8.8' Deg. = 2.5162 + 33.1133*x - 18.3783x +7.3120x 20 -

c0 Deg. = -3.2970 +5.7448*x + 3.6389x +3.1093x 10 -

0 0

0 I

0-2 "49.6 Deg. = -6.1202 + 14.5939'x- 14.04463x + 14.7947*x3

-10*

0.1 0.3 0.5 0.7 0.9 1.1 Radial Distance OD to ID {fractional}

Figure 22: ANO-2 900 azimuth location for all nozzles evaluated. The stress distribution is from the OD to ID.

The coefficients in the respective equations will be used in the fracture mechanics analysis.

The data for WSES-3 nozzles, presented in Table 111, were fit to a third order polynomial in a similar manner. The results of the fitting and the polynomial coefficients are presented in Figures 23 through 26. The equations and coefficients for each of the nozzle location provided in Table I are shown in the respective figure.

The nozzle location is appended to each equation and an arrow points to the respective curve. For the zero degree nozzle, at the ninety degree azimuth location, no curve is provided since the nozzle at this location is symmetric about its axis.

( 3 U

Engineering Report M-EP-2003-002 Rev.

00 Page 30 of 52 WSES-3 Hoop Stress Distribution "O" Degree Azimuth for ID Surface Flaws 25 20 0G15 I,2 0

5 0*

0.1 0.3 0.5 0.7 0.9 1.1 Radial Distance ID to OD {fraction}

Figure 23: WSES-3 downhill location for all nozzles evaluated.

The stress distribution is from the ID to OD. The coefficients in the respective equations will be used in the fracture mechanics analysis.

WSES-3 Hoop Stress distribution "90" Degree Azimuth for ID Surface Flaws Axial elevation 1.544 inches above Nozzle Bottom

'7.8 Deg= 1 6.9507 - 20.11 5O' - 80423'X2 + 01 33-YY 1 4-9-

e 4-I9 I50

-1 -

3 2 529. " Deg = 1.1479 - 15 . 002-x e 7.2549-y

-1 1 - .2587.x3 0.1 n -. I s .:

....... U.7 0.9 1.1 Radial Distance ID to OD {fraction}

Figure 24: WSES-3 90° azimuth location for all nozzles evaluated. The stress distribution is from the ID to OD.

The coefficients in the respective equations will be used in the fracture mechanics analysis.

.... (" I U/

Engineering Report M-EP-2003-002 Rev. 00 Page 31 of 52 WSES-3 Hoop Stress Distribution "0" Degree Azimuth for OD surface Flaws Axial elevation 1.544 inches above Nozzle Bottom 2 3 "0" Deg. = 4.2779 23.2705-x +10.9429.x - 11.0613'x _

25 -

2 "7.8" Deg. = 4.8893 +22.6744x - 12.9657?x + 11.0933 20 -

U215 -

- 5.0827 jx3 8 10 5-0- "49.7" Deg. = 7.1357 - 3.0242-x - 3.3291-x2 +1.8453x 3

l I I I I 0.1 0.3 0.5 0.7 0.9 1.1 Radial distance OD to ID {fraction}

Figure 25: WSES-3 downhill location for all nozzles evaluated. The stress distribution is from the OD to ID. The coefficients in the respective equations will be used in the fracture mechanics analysis.

WSES-3 Hoop Stress Distribution "90" Degree Azimuth for OD Surface Flaws Axial Elevation 1.544 inches above Nozzle Bottom "7.8" Deg. = -2.1933 + 9.1596-x + 1 8.9977.x2 - 9.0133-x3 14 9

In a- 4 0

0

-1

-6

-11 0.1 0.3 0.5 0.7 0.9 1.1 Radial Distance OD to ID {fraction}

Figure 26: WSES-3 90 azimuth location for all nozzles evaluated. The stress distribution is from the OD to ID.

The coefficients in the respective equations will be used in the fracture mechanics analysis.

Engineering Report M-EP-2003-002 Rev. 00 Page 32 of 52 3.0 Fracture Mechanics Analysis Surface Flaw The outside radius-to-thickness ratio (RJt) for the CEDM nozzle was about 3.0.

The fracture mechanics equation used in the proposed revision to the ASME Code Section Xl is based on the solution from Reference 7. This solution is valid for "Rot" ratio from 4.0 to 10.0. Since the CEDM nozzle ROdt ratio is lower indicating that the CEDM nozzle is a thicker wall cylinder than those considered in Reference 7. Therefore the fracture mechanics formulations presented in Reference 8 were chosen (the applicable URJt" ratio is from 1.0 to 10.0).

The SIF for the postulated flaw under the stress distribution presented in the section above was determined using the formulation from the Ductile Fracture Handbook [8a and 8b]. The model chosen was for an intemal part-through-wall flaw subjected to an arbitrary stress distribution. This model is valid for a ratio of the inside radius (Rinner)-to-thickness (t) between 1.0 and 10.0. Since the ratio for the CEDM nozzle is about 2.0, hence this model is considered applicable.

The equation for the stress intensity factor for the deepest point of the crack is given as [8a]:

3 K = () 05 *[Ev G]

t=0 Where:

K, = The SIF ksNin.)

t = The CEDM wal thickness inch]

= Coefficients of the stress polynomial describing the hoop stress variation through the wal thickness fobtained from the previous section).

Gi = Shape factors associated with the stress coefficients defined as:

G = Ao +(Ala, +A 2 a2 +A 3 aqj +A 4 aj4 +A 5 aT)I[0.102(Rj /t)-0.02] 005 Where:

a1 =(alt)1(alp)m R = Inside radius inch) a =Flaw depth inch) c = One half of flaw length (inch)

A and m are the coefficients provided in Reference 8a.

Engineering Report M-EP-2003-002 Rev. 00 Page 33 of 52 The SIF for the surface point of the crack is given as [8a]:

3 K (,z)05 *[EiG]

i=0 Where:

Gs = G1 [A6 + A 7(at) 2]/(aIc)r The coefficients A" and the exponent "r" were obtained from Reference 8a.

The SIF equations for the deepest point and for the surface point are decoupled in this model. This separation enables independent evaluation of the potential for growth at the deepest point and at the surface independently.

The SIF for an external flaw originating on the OD surface was also obtained from Reference 8b and the SIF is given as:

3 K1 = (,) 05 *[Y iG 1 ]

ia=

The above equation is similar to the SIF equation for the deepest point, presented earlier. However, the shape function coefficients are different and are defined [8b] as:

G = AO + (Ala, + A 2 a,2 + 3 a3 ) I(A4 IR,ide / t}-A )

and:

a, =[a/t]/[a/c] m The values for the coefficients "Ax" and the constants n and m"were obtained from Reference 8b. In Reference 8b there was no separate formulation provided for the SIF for the surface point. Therefore, the surface length of the flaw is derived using the aspect ratio (a/c).

To ensure the formulations used in the current report provide a reasonable value for the SIF, a comparison was made with NASGRO-3 [9]. The NASGRO-3 model for the geometry considered was SCO4. The stress distribution for the WSES-3 CEDM nozzle at 7.8 degrees at the downhill location ("O" degree azimuth) was used.

The flaw aspect ratio (a/c) and flaw depth were obtained from the output from the analyses performed for the current evaluation (Appendix 111). The analysis method used in both References 8 and 9 is based on influence function method for an arbitrary stress distribution. The stress coefficients used in Reference 8 use the stress fit to the full thickness of the nozzle, whereas in Reference 9 the stress coefficients are obtained from a fit over the flaw depth. The SIF obtained from the two analyses are presented in Figure 27 for ID (intemal) surface flaws. The comparison shows that the SIF calculated in the current analysis is always greater than those obtained from the analysis performed using Reference 9. The significance of this comparison shows that the SIF obtained in this analysis is conservative and will result in higher PWSCC crack growth rates. A similar comparison for OD (external) flaw

Engineering Report M-EP-2003-002 Rev. 00 Page 34 of 52 was performed and showed that the SIF in the current evaluation was higher than that obtained from Reference 9 ( 5.93 ksiIin vs. 4.34 ksi4in).

Comparison of Stress Intensity Factors NASGRO-3 (SC04) and Present Analysis 50 -

Line of Perfect Agreement

• SIF "Depth"

• SIF"Surface" o 40 -

0) a v 30 c

U)

U)

.U)

• "I 2) a c)10-0-

I I I I I I I 0.000 10.000 20.000 30.000 40.000 50.000 SIF NASGRO-3 {ksi sqrt. inch}

Figure 27: Comparison of SIF from References 8 and 9 utilizing the same stress distribution (WSES-3, 7.80 nozzle at the 0° azimuth at an axial elevation of 1.544" above bottom of nozzle.

Through-Wall Axial Flaw The analysis for a through-wall axial flaw was evaluated using the formulation of Reference 10. This formulation was chosen since the underlying analysis, presented in Reference 10, was performed considering thick wall cylinders that had "Ro/t" ratio in the range of the application herein. The analysis used the outside surface (OD) as the reference surface and, hence, the same notation is used here.

It was noted in Reference 10 that the formulations based on thin shell theory do not consider the complete three-dimensional nature of the highly localized stress distribution. This would be the case for the residual stress distribution from welding.

The nonlinear three-dimensional stress distribution coupled with shell curvature must be properly addressed to account for the material behavior at the crack tip, which controls the SIF, such that the SIF is not underestimated. The information presented in Reference 10 compared the results from formulations derived using thin shell theory

Engineering Report M-EP-2003-002 Rev. 00 Page 35 of 52 and that derived using thick shell formulation which, highlighted the need to use thick shell based formulation for situations such as the current application.

The formulation provides the correction factors, which account for the "RJt" ratio and flaw geometry (), that are used to correct the SIF for a flat plate solution subjected to similar loadings. The correction factors were given for both "extension" and "bending" components. The flat plate solutions for both membrane and bending loads were to be used to obtain the applied SIF. The formulations for SIF were given as [10];

K oaer = {Ae + Ab}

• K For the OD surface;

and, Khme,r = {Ae - Ab }* Kp For the ID surface; where:

Ae and Ab are the extension" and "bending" components; and, Kp is the SIF for a cracked Flat Plate subject to the same boundary condition and loading as the cracked cylinder.

The flat plate SIF solutions are written as:

Kp Membrane = ah* for membrane loading, and Kp-,ewing = b *V7 for bending loading.

Where:

Ah and Jb are the membrane and bending stresses and r is one-half the crack length.

The reference surface used in the evaluation was the OD surface. The stresses at the ID and OD at the axial elevation of interest (1.764 ANO-2 and 1.544 WSES-3 inches above nozzle bottom) were decomposed into membrane and bending components as follows:

a ,res-OD+ are--ID for membrane loading; and 2

ab res-02D cres'f for bending loading.

2

Engineering Report M-EP-2003-002 Rev. 00 Page 36 of 52 where:

Ures-OD iS the residual stress on the OD surface; and, ares-ID iS the residual stress on the ID surface.

The data presented in the tables in Reference 10 for determining the Ae and Ab components were curve fit using a fifth order polynomial such that they could be calculated knowing the parameter X,which is defined as [10]:

A = [12 * (I_V2 )]025 *(R *t) where v is Poisson's ratio and R is the mean radius.

The curve fit results for the components are presented in figure 28 below.

Extension and Bending Constants for Throughwall Axial Flaws R/t = 3.0 r (ASMF PVP 350 1997; pp 143) 2 3 4 5 AeM:- 1.0090 +0.3621'x +0.0565x - 0.0082x +0.0004-x - 8.3264E-006-x to 4-C a

AbB:-

0

,o E

5 2 + 8.8052E-006'x c

0 0-2 3 4 5 AbM :- -0.0063 +0.091 9x - 0.01 68x - 0.0052x + 0.0008x - 2.9701 E-005"x

-2 I~~ I I 0 2 4 6 8 10 12 Parameter Lambda {dimensionless}

Figure 28: Curve fit equations for the "extension and "bending" components in Reference 10. Tables Ic and d for membrane loading and Tables g and h for bending loading of Reference 10 were used.

PWSCC Crack Growth Rate To evaluate the potential for crack growth due to PWSCC, the crack growth rate equation from EPRI-MRP 55 [10] was used. The crack growth rate as a function of the stress intensity factor with a correction for temperature effects is given as [11]:

c-I]~~~~~~~~~~~~~~~~~~

Engineering Report M-EP-2003-002 Rev. 00 Page 37 of 52 d = exp[- Q(T-T )]a(K-Kh)#

dt R TTfJ Where:

da/dt = crack growth rate at temperature T (mls)

Qg = thermal activation energy for crack growth (31.0 kcallmole)

R = universal gas constant (1.103x 103 kcal/mole-oR)

T = absolute operating temperature at crack tip ( 0R)

T = absolute reference temperature for data normalization (1076.67 -RI a = crack growth amplitude (2.67x1Cf 12 J K = crack tip SIF Mpalm)

Kth = threshold SIF for crack growth fMPa4rm

,B= exponent (1.16]

Analysis The surface flaws were modeled such that the upper flaw tip was at the analysis location. This flaw geometry would permit the evaluation of the growth toward the J-weld, which is of interest in this application. The analysis in which potential for PWSCC flaw growth was predicted; the graph for surface flaw growth in the direction of the J-weld was plotted. For the through-wall flaw, the center of the flaw was located at the analysis elevation. When the propensity for PWSCC flaw growth was predicted, growth towards the J-weld was plotted. For each plant, twenty one (21) separate analyses was performed to ensure all possible nozzle geometry, flaw geometry and flaw orientation were addressed.

In the analysis performed, the SIF was calculated both in English and Si units.

The crack growth was first computed in the Si units and then converted to English units. For surface flaws, the initial flaw used was the shallowest detected flaw from the EPRI mockup tests [4] (0.035 inch deep for ID initiated flaws and 0.0665 inch deep for OD initiated flaws). The flaw lengths were based on an aspect ratio of ten (10) as discussed earlier. For through-wall axial flaw, the flaw length used was 0.5 inch. The stress intensity based on the applicable stress intensity was computed and then compared to the threshold SIF. If the SIF was less than the threshold SIF, then no flaw growth would occur. The analysis was performed using a Mathcad [12]

worksheet. The SIF and crack growth equations were solved in a recursive manner for time increments of about one month. Therefore, if growth were to occur (K > Kth),

the crack dimensions could be increased by the amount of growth and the SIF would be recalculated. The Mathcad worksheets utilized in the evaluation for ANO-2 are presented in Appendix II and those for WSES-3 in Appendix III.

Engineering Report M-EP-2003-002 Rev. 00 Page 38 of 52 4.0 Discussion and Results The goal of the inspection program designed for the reactor vessel head penetrations is to ensure that the structural integrity is not challenged during the upcoming operating cycle following the refueling outage when the inspections are performed. Safety analyses performed by the MRP have demonstrated that axial flaws in the nozzle tube material do not pose a challenge to the structural integrity of the nozzle. Axial flaws, if not inspected on a periodic basis can produce a primary boundary leak that can cause damage to the reactor vessel head (carbon steel) and create a conducive environment for initiating and propagating. OD circumferential flaws. These conditions do challenge the pressure boundary and hence critical importance is paid to proper periodic inspection and to the disposition of flaws that may be discovered. Therefore, proper analyses are essential to ascertain the nature of axial flaw growth such that appropriate determination can be accomplished.

The analyses performed in this report were designed to capture the behavior of postulated flaws that might exist in the un-inspected zone. The growth region for the postulated flaws was to the intersection of the J-weld with the tube OD. The flaw growth in the tube in the region of the fillet weld is not considered to challenge the J-weld. Field experience for flaws in the nozzle has demonstrated that propagation is confined to the nozzle base material. Therefore, considering the flaw propagation in the nozzle region adjacent to the fillet weld region is not expected to unduly challenge the J-weld.

In all cases the estimated flaw growth time was limited to the flaw reaching the J-weld to nozzle OD intersection. Hence the J-weld would not be unduly challenged.

The design review of the reactor vessel head construction, the detailed residual stress analyses, the selection of representative nozzle locations, selection of representative fracture mechanics models, and the application of suitable crack growth law has provided the bases for arriving at a comprehensive and prudent decision.

The axial flaw geometry was selected for evaluation because this flaw has the potential for propagation into the pressure boundary weld (the J-groove weld) because the circumferentially oriented flaws will not propagate towards the pressure boundary weld. The hoop stress distribution at the downhill location and at an azimuth ninety degrees were chosen for evaluation because these locations have the closest proximity to the pressure boundary J-groove weld.

The uphill location is farther removed from the J-groove weld; hence the hoop stress is expected to be lower. The axial distribution of the hoop stress magnitude for both the ID and OD surfaces show that at axial location below the evaluated elevation, the stresses drop off significantly; hence potential for PWSCC flaw growth would be significantly lower. If flaws had been postulated flaws in the un-inspected zone on the uphill side, their results would be bounded by the analysis presented herein. Hence no additional analyses are required.

The fracture mechanics evaluation considered the flaw face to be subjected to the operating reactor coolant system (RCS) pressure. This is accomplished by

Engineering Report M-EP-2003-002 Rev. 00 Page 39 of 52 arithmetically adding the RCS pressure to the uniform stress coefficient in the surface flaw analysis and added to the membrane stress for the through-wall flaw analysis. In this manner, the stress imposed on the flaw is accurately and conservatively modeled.

The PWSCC flaw growth used the equations from Reference 8. The operating temperature for the flaw tip was taken to be 604 "F. Thus, the potential for flaw growth is maximized. The seventy fifth percentile curve from Reference 8 was used for calculating PWSCC flaw growth.

The model for evaluation was developed as a coupled stress intensity factor and flaw growth model. The calculations were performed in a recursive manner. The time step for each PWSCC growth block was seventy hours. At the end of the block, the incremental crack growth was doubled and added to the flaw length and a new flaw size was obtained. Therefore, the flaw is expected to grow in both directions.

Using the new flaw length the SIF was computed and the growth for the subsequent block was calculated. This recursive method accounts for concomitant increase of the stress intensity factor as the flaw advances. A small time-step (block) ensures better approximation of the process. The detailed Mathcad calculation worksheets for ANO-2 are presented in Appendix 11and that for WSES-3 in Appendix Ill.

The results of the evaluation are presented in Table IV for ANO-2 and Table V for WSES-3. In these tables the initial SIF at the flaw tip locations evaluated and the corresponding result is provided. When the analysis showed a potential for flaw growth, a figure number is provided, which shows the flaw growth and SIF behavior.

For the ID surface flaws, the behavior of the two flaw tips were independent as mentioned earlier. For the OD surface flaw, SIF could only be computed at the deepest flaw tip and the flaw aspect ratio was used to obtain the surface growth behavior. For the through-wall axial crack cases, the SIF was evaluated at both the ID and OD flaw tips. The flaw growth was computed by using an average of the SIF at these locations.

Engineering Report M-EP-2003-002 Rev. 00 Page 40 of 52 Table IV: ANO-2 Evaluation Results Nozzle Identification Surface Intial Stress Intensity Result/Figure Number Flaw Factor (ksl4ln)

Location on Azimuth on Origin Deepest Surface RV Head Nozzle ID or OD Polnt Point

• 0" Degree Downhill ID 10.32 5.79 PWSCC Growth; Figure 29 8.8' Degree Downhill ID 9.39 5.34 PWSCC Growth; Figure 30

'28.8" Degree Downhill ID 7.07 3.92 No Potential for PWSCC Growth "49.6" Degree Downhill ID 2.06 0.99 No Potential for PWSCC Growth "8.8" Degree 90 Degree ID 7.99 4.51 No Potential for PWSCC Growth "28.8" Degree 90 Degree ID 3.20 1.89 No Potential for PWSCC Growth "49.6" Degree 90 Degree ID 3.06 1.87 No Potential for PWSCC Growth "0" Degree Downhill OD 8.32 NA PWSCC Growth; Figure 31 "8.8' Degree Downhill OD 8.36 NA PWSCC Growth; Figure 32 "28.8" Degree Downhill OD 11.14 NA PWSCC Growth: Figure 33 "49.6" Degree Downhill OD 17.14 NA PWSCC Growth; figure 34 "8.8" Degree 90 Degree OD 3.30 NA No Potential for PWSCC Growth "28.8" Degree 90 Degree OD <0.0 NA No Potential for PWSCC Growth "49.6' Degree 90 Degree OD <0.0 NA No Potential for PWSCC Growth Nozzle Identification Flaw Inital Stress Intensity Result/Figure Number Type Factor Through- (ksNin)

Wall IDSrae D Location on Azimuth on ID SurFace OD RV Head Nozzle surface

'0' Degree Downhill Axial 31.94 18.22 PWSCC Growth; Figure 35 "8.8' Degree Downhill Axial 29.81 18.11 PWSCC Growth; figure 36 "28.8" Degree Downhill Axial 22.95 21.92 PWSCC Growth; Figure 37

• 49.6" Degree Downhill Axial 9.37 31.01 PWSCC Growth; Figure 38 "8.8' Degree 90 Degree Axial 23.98 8.11 PWSCC Growth; Figure 39

• 28.8" Degree 90 Degree Axial 9.82 0.64 No Potential for PWSCC Growth

• 49.6 Degree 90 Degree Axial 9.49 <0 No Potential for PWSCC Growth

Engineering Report M-EP-2003-002 Rev. 00 Page 41 of 52 TableV: WSES-3 Evaluation Results Nozzle Identification Surface Initial Stress Intensity ResultFigure Number Flaw Factor {kslAin)

Location on RV Azimuth on Orlgin Deepest Surface Head Nozzle ID or OD Point Point "0" degree Downhill ID 9.04 5.03 PWSCC Growth, Figure 40 "7.8" Degree Downhill ID 8.19 4.68 PWSCC Growth, Figure 41 "29.1" Degree Downhill ID 4.58 2.58 No Potential for PWSCC Growth "49.7" Degree Downhill ID 1.58 0.84 No Potential for PWSCC Growth "7.8" degree 90 Degree ID 5.67 3.22 No Potential for PWSCC Growth "29.1" degree 90 Degree ID 0.82 0.54 No Potential for PWSCC Growth "49.7" Degree 90 Degree ID 2.12 1.32 No Potential for PWSCC Growth "0 Degree Downhill OD 4.14 NA No Potental for PWSCC Growth

'7.8" Degree Downhill OD 4.34 NA No Potential for PWSCC Growth "29.1" Degree Downhill OD 2.63 NA No Potential for PWSCC Growth "49.7" Degree Downhill OD 4.89 NA No Potential for PWSCC Growth "7.8" Degree 90 Degree OD 0.40 NA No Potential for PWSCC Growth "29.1" Degree 90 Degree OD <0.0 NA No Potential for PWSCC Growth "49.7" Degree 90 Degree OD <0.0 NA No Potential for PWSCC Growth Nozzle Identification Flaw Initial Stress Intensity Resulitgure Number Type Factor Through- (kslAn)

Location on Azimuth on Wail ID Surface l O RV Head Nozzle surface "0" degree Downhill Axial 26.74 10.16 PWSCC Growth; Figure 42 "7.8" Degree Downhill Axial 25.37 10.55 PWSCC Growth; Figure 43 "29.1" Degree Downhill Axial 6.43 14.03 PWSCC Growth; Figure 44 "49.7" Degree Downhill Axial 5.57 9.36 No Potential for PWSCC Growth "7.8" degree 90 Degree Axial 16.68 2.69 PWSCC Growth; Figure 45 "29.1" degree 90 Degree Axial 2.10 <0 No Potential for PWSCC Growth "49.7" Degree 90 Degree Axial 6.00 <0 No Potential for PWSCC Growth The results presented for ANO-2 and WSES-3 demonstrate that flaw growth is possible for some penetration locations at the location evaluated. The time needed for the flaw to grow to the J-weld interface is obtained by subtracting the un-inspectable length height from the nozzle projection below the J-weld, (Apendix ;

Engineering Report M-EP-2003-002 Rev. 00 Page 42 of 52 ). The growth distance was estimated from the inspection lower limit to the J-weld intersection for a particular nozzle location. The available length for flaw growth for the nozzles considered in this analysis are presented in Table VI. Since the stresses at locations below the current flaw location are at significantly lower magnitude of stress (including compressive), it is not plausible that PWSCC flaw growth could occur at elevations below the evaluated position. Therefore, the region that cannot be inspected is not expected to negatively impact the structural and leak integrity of the primary pressure boundary at the reactor vessel head penetrations.

Table VI Available Nozzle Length for (PWSCC) Flaw Growth Nozzle Location Freespan Nozzle Un-Inspected Length Length available for Flaw Length above Nozzle Bottom Growth (inch) (inch) finch)

ANO-2 0'degree; downhill 2.48 1.764 0.716 z.degree; downhill 2.48 1.764 0.716 "28.8'dbiree; downhill -2.48 1.764 0.716 496gdgre, downhill 2.48 1.764 0.716

.8 degree; inety degrees 2.83 1.764 1.066 WSES-3

-0egree, ffioWnhill 2.88 1.544 1.336 7:8raeijee; downhill 2.88 1.544 1.336 291deee; downhill 2.88 1.544 1.336 72gree,downhill 2.88 1.544 1.336 7gzegre ety7derees 3.185 1.544 1.641 For those analysis cases where PWSCC growth was observed, the behavior of crack growth as a function of operating time are presented in Figures 29 through 45.

In these figures the behavior of SIF is also presented. Figures 29 through 39 provide the information for ANO-2 CEDM nozzles and Figures 40 to 45 for WSES-3 CEDM nozzles.

Engineering Report M-EP-2003-002 Rev. 00 Page 43 of 52

~~~~~~~~~oII 1 loonOnf 13.12 II I-I S

o~~~~~~~~~~~~~~~~~~~~~~~

I 0 2 4 6 8 10 12 01 0 4 PWSCIj ) 201 0 2 4 6 t to 12 14 16 IS 20

.005 PWSCC, , 20 Oprolig 11i-1 Yaaro}

-Dep,s MPoint

(*..i.g T.e D-

-- I 0Surxco Figure 29: ANO-2; Plots for an ID surface crack growth and SIF versus operating time for the 00 nozzle at the 00 azimuth (downhill position). The assumed flaw reaches the J-weld interface in 13.12 operating years. (source: Appendix II, Attachment 1) 60 2

2 I I

'VSC I8;u PWS(

,5 137 o.l

,004 PWSC48. " 25 I

15 2 2S

- De-po Pon CV13,J81,-,I0

'llI. - '10 Th

-- O Sodacc llpol,,g oo 10000i Figure 30: ANO-2; Plots for an ID surface crack growth and SIF versus operating time for the 8.80 nozzle at the 0 azimuth (downhill position). The assumed flaw reaches the J-weld interface in 17.56 operating years. (source: Appendix II, Attachment 4) 2 ~ ~~~~~~~~

.ingl olflow on Sorlaco 9(1 20 2118 I

j: I S

S'P sq-vsPWCi ; / 0716 178 fs 2

20 0

0 11 o 1 Is 20 25 "I ZS .161)0 PWSC& 6

1) 25

,PA11< PWSC6. 1o Deepet Poit Operatinglimc Yar' Figure 31: ANO-2; Plots for an OD surface crack growth and SIF versus operating time for the 0° nozzle at the 0° azimuth (downhill position). The assumed flaw reaches the J-weld interface in 20.90 operating years. (source: Appendix II, Attachment 8)

Engineering Report M-EP-2003-002 Rev. 00 Page 44 of 52 90 2

1 t

7 1 i I 7.

t'WC%e

-:11WSC,,

4 I 178

-4I

~~~~I I 1 15 20 25 25

,?A,' PWSt2% 25 55

,S~~~~~~~~~~i

.040~~~~~Opnn .im PU'SC Ii03 Pwsc¶>

D)peetig ime {Ycer.I

- Deepest Point Figure 32: ANO-2; Plots for an OD surface crack growth and SIF versus operating time for the 8.80 nozzle at the 0° azimuth (downhill position). The assumed flaw reaches the J-weld interface in 19.02 operating years. (source: Appendix II, Attachment 9) t.-gth of 1a on tSd-90 05 T ~ ~~~~~~~~~~~~

I?

2 I

I,5 I71. I i 178 0.716 2

c .2

.0. t) 2 1 4 S 6 7 XX 0 1 2 3 4 S 8 S 6 7 9 I0 .tb Mm-, PWgsz , Y a.thtt3. PWSCS,, to OtpeetigTimc IYnl - Deepest Poil pttt tm et Figure 33: ANO-2; Plots for an OD sufface crack growth and SIF versus operating time for the 28.80 nozzle at the 0° azimuth (downhill position). The assumed flaw reaches the J-weld interface in 4.58 operating years. (source: Appendix II, Attachment 10)

Length ol Sft let Suefce /

iz

/IPO71

,-PWS%C_,

5-I

_i 0 0.5 1 L5 3

(>;, , . .. . ..

I 15 2 2.5 3 ,XN40', PwscJ, PWSCqY: b Operdng ime Ys

- Deepest Point Op-tJ ig ime lY- ns Figure 34: ANO-2; Plots for an OD surface crack growth and SIF versus operating time for the 49.60 degree nozzle at the 0° degree azimuth (downhill position). The assumed flaw reaches the J-weld interface in 2.01 operating years. (source: Appendix II, Attachment 11)

Engineering Report M-EP-2003-002 Rev. 00 Page 45 of 52 Fa .nh sTime 1; ~~~~ ~~~~~12222g 6 /222 I I :2 II z2_

N TWC _sae 3i 362.

I~~~~~~~~~~~~~~~~~~~~~~ ;6 73 I I

oS 9 1 2 1 3 4 S 2 759 2 l 3

05222.222.5 2222222 222..221 I

.220. I >KW im3,,,yn 122Cf' 1

.929J. T9 C ,

- ODSIF -

---

ID)SiF Figure 35: ANO-2; Plots for a through-wall axial crack growth and SIF versus operating time for the 0° nozzle at the O azimuth (downhill position). The assumed flaw reaches the J-weld interface in 3.52 operating years. (source: Appendix II, Attachment 15)

Fl.. I-Slh ,.Ti- 1I99 I-I5 i

I t "I",", "¢ I

I . I I

,2 o.5 I

9

o. 1 2 3 4 5 6 I 8 9 lo

,or-\C 7,L 10 99S OUfl _,, 1,-

- -- IDSIF Figure 36: ANO-2; Plots for a through-wall axial crack growth and SIF versus operating time for the 8.80 nozzle at the 0° azimuth (downhill position). The assumed flaw reaches the J-weld interface in 3.80 operating years. (source: Appendix II, Attachment 16) w /'~~~~

69 ftto //I

.2T6 63 3~~~~~

I.

o . , . .~

11-3sm-, cl-TWC,.

ip 2222 I I Figure 37: ANO-2; Plots for a through-wall axial crack growth and SIF versus operating time for the 28.80 nozzle at the 0 azimuth (downhill position). The assumed flaw reaches the J-weld interface in 4.16 operating years. (source: Appendix II, Attachment 17)

Engineering Report M-EP-2003-002 Rev. 00 Page 46 of 52 iF i

L i I

.I 2 4 6

,o 4, TWC ,',j. "

0 1 2 3 4 5 6 7 I(

.0W TW7w, 1 10 Oc-mng Tim IYe5r

- OD SIF Oper-ong Fime1 e6T6 -- I1SIF Figure 38: ANO-2; Plots for a through-wall axial crack growth and SIF versus operating time for the 49.6° nozzle at the 0 azimuth (downhill position). The assumed flaw reaches the J-weld interface in 4.88 operating years. (source: Appendix II, Attachment 18)

Fl.. 1ouOh i-161 9i7 i E /~~~~~~~~~~~7

/ 106~~[

I 4*0

,IV9Ss, eI-I 0 2 4 6 8 10 12 14 I16 15 .604. \c,, 15

- OD0sF 3a-ggTi (-.

OPeing-Ti- l - ID

-IF Figure 39: ANO-2; Plots for a through-wall axial crack growth and SIF versus operating time for the 8.80 nozzle at the 900 azimuth. The assumed flaw reaches the J-weld interface in 9.72 operating years. (source: Appendix II, Attachment 19)

The graphs for the SIF for surface flaws (ID initiated) show that the surface SIF is higher than the SIF at the deepest penetration; hence, it follows that the flaw growth would tend to be higher on the surface than in the through-thickness direction. This behavior is observed in flaws that have been found in-service where the crack profile has a "canoe" shape rather than a semi-elliptical profile. The information obtained from the graphical results, such as time to reach J-weld intersection and the final SIF at that time, are provided in Table VII for ANO-2.

Engineering Report M-EP-2003-002 Rev. 00 Page 47 of 52 Table VIl: ANO-2 Results for PWSCC Growth Cases "8.8" Degree Downhill ID 34.62 49.75 17.56.

"0" Degree Downhill OD 26.32 NA 20.90 "8.8" degree Downhill OD 23.71 NA 19.02 "28.8" Degree Downhill OD 30.76 NA 4.58 Location onbRw4 , tSg,,,lt Azim C ;:e>,gID Sldc >e swac {Q"rUn Years)

Ha doze.

"0"Degree Downhill Axial 61.54 46.66 3.52 "8.8" Degree Downhill Axial 57.77 45.99 3.8 "28.8" Degree Downhill Axial 47.88 50.17 4.16 "49.6" Degree Downhill Axial 28.93 60.52 4.88 "8.8" Degree 90 Degree Axial 60.52 40.86 9.72 i

~2 I 5 10 15 20 25 4) 5 10 15 20 25

,rl 0; a'WSO To - Deepest Point Opeating limc Yenes)

Opr-ting Ti- Y,! -. On Surface Figure 40: WSES-3; Plots for an ID surface axial crack growth and SIF versus operating time for the 0° nozzle at the 0 azimuth (downhill position). The assumed flaw reaches the J-weld interface in 23.44 operating years. (source: Appendix I, Attachment 1)

Engineering Report M-EP-2003-002 Rev. 00 Page 48 of 52 I-gl2h f116 fl o Stc-1c I.

156~

1~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11(

l 92PWK2Cj,

- P scq.,

61 5

2 I 06 0 1 0 5 .0 3

,468 (R51 5 20 2 U 1 I 10 4(1 Pw633 11 u6N JU Opoingitt Y3,,

O 15W20 25 "I 55 4 D04 pWScqj. - D0033033 P-m3 rime13 -31 n-pem.333 -- 0h Suac Figure 41: WSES-3; Plots for an ID surface axial crack growth and SIF versus operating time for the 7.80 nozzle at the 0° azimuth (downhill position). The assumed flaw does not reach the J-weld interface in 40 operating years, because the SIF was barely above the threshold value(source: Appendix II, )

,n7 5 6

.633, 10

- CF TIII Figure 42: WSES-3; Plots for a through-wall axial crack growth and SIF versus operating time for the 0 nozzle at the 0° azimuth (downhill position). The assumed flaw reaches the J-weld interface in 8.56 operating years. (source: Appendix I, Attachment 15) 2 2 1, e3Wlcgh,1im6 0U6U e5 336ACvsj)6 46i0w,3/;r... .3' 3-3 --

4 0 2 a 6 4 ,04 T3346.33 lU 5

.0 4 TWC-t-,

- OD SIF 3re3-m33i I l .. IDSIF Figure 43: WSES-3; Plots for a through-wall axial crack growth and SIF versus operating time for the 7.8° nozzle at the 0° azimuth (downhill position). The assumed flaw reaches the J-weld interface in 8.92 operating years. (source: Appendix I, Attachment 16)

_ __ _ _ _ _ _ _ _ ~ 23

~~~C-

Engineering Report M-EP-2003-002 Rev. 00 Page 49 of 52

,11 50 50

• 2 I

_ l o

20

... ,...- =-

0 5 I0 15 22 25 lo 35 I

4 II 5 1M IS 20 25 30 35 4(

.5104. ~~~~IWC pl,1

- ODSSIF ONO$gl0m l.,,l

- . IDSIF Opnrslig Ti.. -12,2 Figure 44: WSES-3; Plots for a through-wall axial crack growth and SIF versus operating time for the 29.10 nozzle at the O azimuth (downhill position). The assumed flaw reaches the J-weld interface in 28.08 operating years. (source: Appendix I, Attachment 17)

FlavLengths Time 102

/ 64 I I t 3 a

0 0 S 10 1 20 25

.004, IWC ,1 -o 4(

(o 5 I )5 20 25 30 35 40 (4 40

- ODSIF Oi8 I0, -

porotm8li-g To -1 ---- IDSl:

Figure 45: WSES-3; Plots for a through-wall axial crack growth and SIF versus operating time for the 7.8nozzle at the 90° azimuth. The assumed flaw reaches the J-weld interface in 35.52 operating years. (source: Appendix I, Attachment 19)

As was observed in the graphs for ANO-2, the WSES-3 graphs show similar trends. The SIF for surface flaws (ID initiated) show that the surface SIF is higher than the SIF at the deepest penetration. The information obtained from the graphical results, such as time to reach J-weld intersection and the final SIF at that time, are provided in Table VIII for WSES-3.

(-~~~~~~~~~~~

Engineering Report M-EP-2003-002 Rev. 00 Page 50 of 52 TableVill: WSES-3 Results for PWSCC Growth Cases N&2161dintification Suface FinalStress Intensity Time to Reach J-Weld Intersection Flaw Factor (ksln)

Location on RV Azimuth on 9 Deepest Surface (Operating Years)

Head Nozzle ID or OD Point Point

'0'degree Downhill ID 35.00 49.39 23.44 7.8- Degree Downhill ID 8.26 4.77 >40 Nozzle Identification Flaw Final Stress:Intensity Time to Reach J-Weld lntersection Type Factor Through- (ksl4in)

Wall (Operating Yeams Location on RV Azimuth on ID Surface OD surface Head Nozzle

.0 Vdegree Downhil X Axial 84.05 62.72 8.56 7.8 Degree Downhill Axial 80.68 67.65 8.92

'29.1" Degree Downhill Axial 46.46 36.58 28.08

'7.8" degree 90 Degree Axial 58.68 36.43 35.56 5.0 Conclusions The evaluation performed and presented in the preceding sections support the following conclusions:

1) The shortest PWSCC growth time for ANO-2 is a part through-wall OD axial flaw on the 49.6 degree nozzle at the downhill location. The growth time to reach the J-weld interface was calculated to be 2.01 years. This time is in excess of one operating cycle of eighteen (18) months.

2) The shortest PWSCC growth time for WSES-3, is for a through-wall axial flaw for the central CEDM location ("0" degree). The growth time to reach the J-weld interface was calculated to be 8.56 years. This time is in excess of five operating cycles of eighteen (18) months duration.

3) The conservatisms used in the analysis (pressure applied to flaw faces and high aspect ratio) provide assurance that an undetected flaw at the lowest elevation for inspection will not reach the J-weld interface within one operating cycle. Therefore adequate opportunities exist to detect the postulated flaw before it reaches the J-weld.

Engineering Report M-EP-2003-002 Rev. 00 Page 51 of 52

4) The regions below the lowest inspection elevation experience lower stresses and, hence, significantly lower potential for flaw growth by PWSCC. Therefore at these lower locations PWSCC flaw growth is not expected.

5) The analysis presented herein demonstrates that there will be no negative impact on the level of quality and safety by excluding the un-inspectable region, (1.764 inches for ANO-2 and 1.544 inches for WSE-3), at the bottom of the CEDM nozzle. Therefore, the proposed inspection extent provides an acceptable level of quality and safety.

6.0 References

1) NRC Order; Issued by letter EA-03-009 addressed to "Holders of Licenses for Operating Pressurized Water Reactors"; dated February 11, 2003.

2) Drawing Number M-2001-C2-23, ANO Design Engineering Drawing files &

1564-506 WSES-3 Design Engineering Drawing files.

3) a: E-mail from R. V. Swain (Entergy) to J. G. Weicks (Entergy); Dated 5/15/2003.

b: E-mail from R. V. Swain to J. G. Weicks; Dated 5/12/2003.

4) EPRI NDE Demonstration Report; MRP Inspection Demonstration Program -

Wesdyne Qualification": Transmitted by e-mail from B. Rassler (EPRI) to K. C.

Panther (Entergy); Dated 3/27/2003.

5) a: DEI Calculation titled " ANO Unit 2 CEDM and ICI Stress Analysis- Using Monotonic Stress Strain curves"; Calculation Number C-7736-00-5; dated 2/5/2002.

b: DEI Calculation titled " Waterford 3 CEDM and ICI Stress Analysis- Using Monotonic Stress Strain curves"; Calculation Number C-7736-00-4; dated 2/4/2002.

6) Axxum 6; Data Analysis Products Division, Mathsoft Inc., Seattle, WA; February 1999.

7) "Stress Intensity Factor Influence Coefficients for Intemal and External Surface Cracks in Cylindrical Vessels"; I. S. Raju and J. C. Newman, Jr.; ASME PVP Volume 58 "Aspects of Fracture Mechanics in Pressure Vessels and Piping";

1982.

Engineering Report M-EP-2003-002 Rev. 00 Page 52 of 52

8) a: "Ductile Fracture Handbook - Volume 3, Chapter 8, section 1.5"; Electric Power Research institute; NP-6301-D-V3; June 1989 b: "Ductile Fracture Handbook - Volume 3, Chapter 8, section 1.9"; Electric Power Research institute; NP-6301-D-V3; June 1989NASGro

9) "NASA- NASGRO 3.0 "A Software for Analyzing Aging Aircraft"; S. R. Mettu etal.; Scientific and Technical Information; NASA; Report Number STI-19990028759; 1999.

10) New Stress Intensity factor and Crack Opening Area Solutions for Through Wall Cracks in Pipes and cylinders": Christine C. France, etal.; ASME PVP Volume 350 "Fatigue and Fracture"; 1997.

11) "Materials reliability Program (MRP) Crack Growth Rates for Evaluating Primary Water Stress Corrosion cracking (PWSCC) of Thick Wall Alloy 600 Material": MRP-55 Revision 1; Electric Power Research Institute; May 2002.

12) Mathcad - 11; Data Analysis Products Division; Mathsoft Inc.; Seattle WA; November 2002.

ENCLOSURE 4 APPENDIX I ENGINEERING REPORT M-EP-2003-002

Engineering Report: M-EP-2003-0002 Rev. 00 Appendix I Appendix I

. Attachment Attachment Content Number 1 Data Input Concurrence from ANO 2 Data Input Concurrence from WSES-3 3 NDE Dead Zone Information 4 Determination & Verification of CEDM Freespan for ANO-2 and WSES-3

Design Input Sheet for Fracture Mechanies Evaluation of CEDM nozzles below the Attachment J-weld (ANO Unit 2 and WSES Unit 3) iW.~~~~~~M ' * -~~~~~~~~~~~~~~-M I

Length from bottom of nozzle to Drawing M-2001-C2-23 1.25 inches Site Desigi) Engeqrmg top of thread relief counterbore revision 4 (CE drawing E- ANO: Jamie GoBell (includes 1 inch thread length plus 234-760-2) ANO-2 WSES3:

'/4 inch thread relief counterbore) E-74170-112-01 WSES-3 Maximum Chamfer Dimension Same Drawing as above 0.094 inches Site Desi along the axis of the nozzle, AN0: Jamie GoBell including 1/32" tolerance WSES3:

'EL A477 3 Swain's Notes of

• Rie 0.300 4/23/03 attc ANO:

4/23/03 I.J Co3 Residual Stress Distribution DEI calculations: Nodal stresses below J- DEI Calculations were performed for Wes.tghouse C-7736-00-5 ANO-2 weld under contract to Westinghouse for ANO-2 and C-7736-00-4 WSES-3 WSES3 RVHP evaluations. Wesbngbouse (OEM}

provided design input Westighouse and DEI have Appendix "B" qualified QA progran and these calculations were performed under the applicable program This provides reasonable assurmce that the results are applicable.

PWSCC Crack Growth rate EPRI-MRP 55 revision 1. Seventy-fifth Permentile EPRI report based on information provided by all Curve utilities and the analyses for the report was performed under EPRI QA program The report was reviewed by Utlity peer group {MRP) for correctness, completeness and applicability. The information is reasonable for use for ANO-2 and WSES-3 application.

Nozzle Dimensions (ID and OD) Drawing M-2001-C2-23 OD = 4.05"; ID = 2.719" Site Desim EngneeKn&:

revision 4 (CE drawing E- OD = 4.05"; ID = 2.719" ANO:_Jamie GoBell mg.

234-760-2) ANO-2 WSE3 _ _ _

E-74170-112-01 WSES-3 ___ *

- Co 1: Concurrenceis only requiredforitems that have a signatureblock The Residual Stress results and PWSCC crackgrowthratereporthave been provided under approved QA programsand there is reasonableassuranceofthe result's accuracy. Hencefor these two items specific concurrence is not required. 3 ( ;L CD o0

~~~~~~~~~~~ I 1- I Design Input Sheet for Fracture Mechanics Evaluation of CEDM nozzles below the Attachment J-weld (ANO Unit 2 and WSES Unit 3)

Thread length E-234-760-2 ANO-2 1.25 inches Site Desig Engineering:

E-74170-112-01 WSES-3 ANO:

WSES3:TiJ Chamfer Dimension Same Drawing as above 0.094 Site Design Engineering.

ANO: 1i WSES3- vzo &

MSSe 73_C_

RQ~~~~~--Knae SwainsNotes of 0.300__

P07V44/230 ANO:

owAGc,

-- ,egV 23/0 -4123/03 5.

to Residual Stress Distribution 6/'R7 DEI calculations: Nodal stresses below J- DEI Calculations were performed for Westinghouse

,, Reidual tressDistriutionC-73605 ANO-2 weld under contact to Westinghouse for ANO-2 and 0 C-7736-00W WSES-3 WSES3 RVHP evaluations. Westinghouse OEM) 10

S provided design input. Westinghouse and DEI have rr Appendix "B" qualified QA program and these la (E.

calculations were perforned under the applicable progran. This provides reasonable assurance that the S results are applicable.

eD  :.

PWSCC Crack Growth rate EPRI-MRP 55 revision 1. Seventy-fifth Percentile EPRI report based on infornation provided by all Curve utilities and the analyses for the report was performed under EPRI QA progamm. The report was reviewed by

a. ~0 cm S

Utlity peer group {MRP} for correctness, 0

EPO completeness and applicability. The infonnation is reasonable for use for ANO-2 and WSES-3 application.

Nozzle Dimensions {ID and OD) E-234-760-2 ANO-2 OD = 4.05"; ID = 2.719" Site Design Engineering:

E-74170-112-01 WSES-3 OD = 4.05"; ID = 171 ANO: K o)

C

. WSE3:

1: Concurrence is onlyrequiredforitems that have asignatureblock The ResidualStress results andPWSCCcrackgrowthratereporthave S.1 beenprovidedwiderapprovedQAprograms andthere is reasonableassuraneeofthe result's accuracy. Hencefor these two items specific concurrenceis not required.

- o

t. o

Engineering Report: M-EP-2003-002 Rev. 00 Appendix ; Attachment 3 NDE Dead Zone Design Input June 6, 2003 Design Input to Engineering Report M-EP-2003-002:

At the request of Entergy, Westinghouse reviewed UT data for 10 penetrations taken from the 2R15 ANO-2 reactor head Inspection. This Inspection was performed with a 7010 ultrasonic end-effector, using 0.250' diameter, 24mm PCS ime-of-Flight-Dtffraction ultrasonic transducers. The penetrations were chosen by their location on the head, in order to provide a representative sample of the entire head. The analysis was performed Inorder to determine the ultrasonic dead band located Immediately above the threaded region of the CEDM nozzles. This revlew detemined the dead band to be 0.200'.

Ronald V. Swain UT Level IlIl Waterford 3 SES

Engineering Report: M-EP-2003-002 Rev. 00 Appendix I; Attachment 4 Page 1 of2 ANO-2 & WSES-3 CEDM Freespan Measurement To support the crack growth rate evaluation for the portion of the CEDM nozzle that extends below the J-groove weld on the ANO-2 and W-3 heads, the length of this portion of the nozzle is required. Because this length varies with the nozzle location, an Excel spreadsheet was developed to calculate the various parameters of the nozzle J-groove weld configuration.

To describe the geometry, the following nomenclature is used: The location of the nozzle relative to the curvature of the head is identified by the angle in degrees between the vertical centerline of the head, and a line created by the radius of curvature of the bottom surface of the cladding where it intersects with the centerline of the nozzle. The nozzle locations included in the crack growth rate evaluation are identified as the following:

ANO-2 Waterford-3 Nozzle location Penetration No. Nozzle location Penetration No.

o I 00 _

8.80 2,3,4,5 7.8° 2,3 28.80 30, 31, 32, 33, 34, 29.10 36, 37, 38. 39,40, 35, 36, 37 41,42, 43 49.6 7 71 72, 73, 74, 49.7" 88, 89, 90, 91 75, 76, 77,78,79,

_____________ 80,81 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

The point location around the OD of the nozzle is identified by the azimuth angle with the zero degree azimuth location being the point furthest from the vertical centerline of the head, which is also the lowest point that the lgrove weld attaches to the nozzle (the 'low-hillside"). The length of the portion of the nozzle that extends down below the J-groove weld is calculated at the zero degree azimuth for each of the nozzle locations evaluated.

The length, 'L", of the portion of the nozzle that extends down below the J-groove weld is deined as the vertical distance from the point where the surface of the cladding would intersect with the outside surface of the nozzle at the zero degree azimuth location down to the botton of the nozzle (see attached sketch).

Using ANO drawings M-2001-C2-23, M-2001-C2-26, M-2001-C2-32, M-2001-C2-55, and M-2001-C2-107, and Waterford drawings 1564-506, 1564-1036, and 1564-4086, the length "L" was calculated as shown in the following table:

ANO-2 _ Waterford-3 Nozzle location L (inches) Nozzle location L inches]

00 2.50 0" 2.88 8.8 2.49 7.8' 2.88 28.8° 2.48 29.1° 2.86 49.6° 2.48 49.7° 2.92 Verified by:

l , N0-2 I Waterford-3 I 2= AMU t1, 6/4/03 IW Ke 1 6/4/03 I / Jamie GoBell I Date_ NaraRay_l I Date

0 CD~~~~~~~~~

E I 0~~~~~~~~~~~~t