ML18153A755
| ML18153A755 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 05/31/1995 |
| From: | Beth Brown, Feige E, Hall K IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY |
| To: | NRC (Affiliation Not Assigned) |
| Shared Package | |
| ML18153A750 | List: |
| References | |
| CON-FIN-L-2556 INEL-95-0280, INEL-95-280, NUDOCS 9509120068 | |
| Download: ML18153A755 (34) | |
Text
ENCLOSURE 2 INEL-95/0280 Technical Evaluation Report on the Third 10-year Interval lnservice Inspection Program Plan:
Virginia Electric and Power Company, Surry Power Station, Unit 2, Docket Number 50-281 B. W. Brown E. J. Feige K. W. Hall A. M. Porter Published May 1995 Idaho National Engineering Laboratory Materials Physics Department Lockheed Idaho Technologies Company Idaho Falls, Idaho 8341 5 Prepared for the Division of Engineering Office of Nuclear Reactor Regulation U.S. -Nuclear Regulatory Commission Washington, D.C. 20555 Under DOE Idaho Operations Office Contract DE-AC07-94ID13223 FIN No. L2556 (Task Order 46) 9509120068 950830
.. . PDR ADOCK 05000281
- G PDR
ABSTRACT This report presents the results of the evaluation of the Surry Power Station, Unit 2, Thtrd JO-Year Interval Inservice Inspection Program Plan, Revision 0, submitted March 18, 1994, including the requests for relief from the American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, requirements that the licensee has determined to be impractical. The Surry Power Station, Unit 2, Third JO-Year Interval Inservice Inspection Program Plan, Revision O is evaluated in Section 2 of this report. The Inservice Inspection (ISI} Program Plan is evaluated for (a} compliance with the appropriate edition/addenda of Section XI, (b} acceptability of examination sample, (c} correctness of the application of system or component examination exclusion criteria,. and (d} compliance with !SI-related commitments identified during previous Nuclear Regulatory Commission reviews. The requests for relief are evaluated in Section 3 of this report.
This work was funded under:
U.S. Nuclear Regulatory Commission FIN No. L2556, {Task Order 46}
Technical Assistance in Support of the NRC Inservice Inspection Program ii
e
SUMMARY
The licensee, Virginia Electric and Power Company, has prepared the Surry Power Station, Unit 2, Third 10-Year Interval Inservice Inspection Program Plan, Revision 0, to meet the requirements of the 1989 Edition of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel ~ode,Section XI. The third IO-year interval began May 10, 1994 and ends May 9, 2004.
The information in the Surry Power Station, Unit 2, Third 10-Year Interval Inservice Inspection Program Plan, Revision 0, submitted March 18, 1994, was reviewed. Included in the review were the requests for relief from the ASME Code Section XI requirements that the licensee has determined to be impractical. As a result of this review, a request for additional information (RAI) was prepared describing the information and/or clarification required from the licensee .in order to complete the review. The licensee provided the requested information in the submittal dated November 28, 1994.
Based on the revi~w of the Surry Power Station, Unit 2, Third 10-Year Interval Inservice Inspection Program Plan, Revision 0, the licensee's response to the Nuclear Regulatory Commission's RAI, and the recommendations for granting relief from the ISI examinations that cannot be performed to the extent required by Section XI of the ASME Code, no deviations from regulatory requirements or commitments were identified in the Surry Power Station, Unit 2, Third 10-Year Interval Inservice Inspection Program Plan, Revision 0.
iii
- CONTENTS ABSTRACT ii
SUMMARY
. ii i
- 1. INTRODUCTION 1
- 2. EVALUATION OF INSERVICE INSPECTION PROGRAM PLAN 4 2.1 Documents Evaluated 4 2.2 Compliance with Code Requirements 4 2.2.1 Compliance with Applicable Code Editions . 4 2.2.2 Acceptability of the Examination Sample 4 2.2.3 Exemption Criteria . 5 2.2.4 Augmented Examination Commitments 5 2.3 Conclusions 6
- 3. EVALUATION OF RELIEF REQUESTS 7 3.1 Class I Components . . . . . 7 3.1.1 Reactor Pressure Vessel 7 3.1.1.1 Request for Relief SR-001, Examination Category 8-F, Item BS.IO, Reactor Vessel Nozzle-to-Safe End Butt Welds . . . . . . . . . . . . . . . . . . . . . . . 7 3.1.1.2 Request for Relief SR-007, IWA-2610, Weld Reference System for The Reactor Vessel and Vessel Nozzle Area . . 9 3.1.2 Pressurizer 10 3.1.2.1 Request for Relief SR-003, Examination Category B-D, Item B3.120, Examination of the Pressurizer Surge Nozzle Inside Radius Section . . . . . . . . . . . . . 10 3.1.2.2 Request for Relief SR-011, Examination Category B-B, Items B2.ll and B2.12, Examination of the Pressurizer Head-to-Shell Weld and Associated Longitudinal Weld 12
- 3. L 3 Heat Exchangers and Steam Generators . . . . . . . . . . 14 3.1.3.1 Request for Relief SR-002, Examination Category B-D, Item 83.140, Steam Generator (Primary Side) Nozzle Inside Radius Section . . . . . . . . . . . . . . . 14 iv
- e 3.4.3.3 Request for Relief 4, IWD-5223, System Hydrostatic Test of Class 3 Auxiliary Feedwater (AFW) 29 3.4.4 General 32 3.4.4.1 Request for Relief 5, IWA-5250(a)(2), System Pressure Test Corrective Measures . . . . . . . . . . 32 3.4.4.2 Request for Relief 6, IWA-5242(a), System Pressure Tests for Insulated Components 34 3.5 General .
. . . . . . . . . . . . . . . . . .. 36 3.5.1 Ultrasonic Examination Techniques 36 3.5.1.1 Request for Relief SR-005, ASME Section V, Article IV, Figure T-441.1 and Section XI, Appendix III, Figure 111-3230-2, Requirements for Ultrasonic Calibration Blocks .......... . 36 3.5.2 Exempted Components (No requests for relief) 3.5.3 Other . 38 3.5.3.1 Request for Relief SR-012, Request for Authorization to Use ASME Code Case N-524. . . . . . . . . . . . . . . . 38 3.5.3.2 Request for Relief SR-006, Weld Reference System for Class 1 and Class 2 Piping, Vessels, and Components 40 3.5.3.3 Request for Relief SR-009, Request Authorization to Use ASME Code Case N-509 . 42
- 4. CONCLUSION 44
- 5. REFERENCES 46 vi
e TECHNICAL EVALUATION REPORT ON THE THIRD 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN:
VIRGINIA ELECTRIC AND POWER COMPANY, SURRY POWER STATION, UNIT 2, DOCKET NUMBER 50-281
- 1. INTRODUCTION Throughout the service life of a water-cooled nuclear power facility, 10 CFR 50.55a(g)(4) (Reference 1) requires that components (including supports) that are classified as American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Class 1, Class 2, and Class 3 meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components (Reference 2), to the extent practical within the limitations of design, geometry, and materials of construction of the components. This section of the regulations also requires that inservice examinations of components and system pressure tests conducted during successive 120-month inspection intervals comply with the requirements in the latest edition and addenda of the Code incorporated by reference in 10 CFR 50.SSa(b) on the date 12 months prior to the start of the 120-month inspection interval, subject to the limitations and modifications 'listed therein. The components (including supports) may meet requirements set forth in subsequent editions and addenda of the Code that are incorporated by reference in 10. CFR 50.55a(b) subject to the limitations and modifications listed therein, and subject to Nuclear Regulatory Commission (NRC) approval.
The licensee, Virginia Electric and Power Company, has prepared the Surry Power station, Unit 2, Third JO-Year Interval Inservice Inspection Program Plan, Revision 0, (Reference 3), to meet the requirements of the 1989 Edition of the ASME CQde Section XI. The third 10-year interval began May 10, 1994 and ends May 9, 2004.
As required by 10 CFR 50.55a'(g)(5), if the licensee determines that certain Code examination requirements are impractical and requests relief from them, the licensee shall submit information and justification to the NRC *to support that determination.
1
The requests for relief are evaluated in Section 3 of this report. Unless otherwise stated, references to the Code refer to the ASME Code,Section XI, 1989 Edition. Specific inservice test programs for pumps and valves are being evaluated in other reports.
3
2.2.3 Exemption Criteria The criteria used to exempt components from examination shall be consistent with Paragraphs IWB-1220, IWC-1220, IWC-1230, IWD-1220, and 10 CFR 50.55a(b). The exemption criteria have been applied by the licensee in accordance with the Code, as discussed in the ISi Program Plan, and appear to be correct.
2.2.4 Augmented Examination Commitments In addition to the requirements in Section XI of the ASME Code, the licensee has committed to perform the following augmented examinations:
(a) Reactor vessel examinations in accordance with the requirements of NRC Regulatory Guide 1.150, Ultrasonic Testing of Reactor Vesse.7 Welds During Preservice and Inservice Examinations, Revision 1, (Reference 7);
(b) Volumetric examination of the reactor coolant pump flywheel high stress areas every 3 years, as well as volumetric and surface examinations with the flywheel removed at IO-year intervals, satisfying NRC Regulatory Guide 1.14, Reactor Coolant Pump Flywheel Integrity, (Reference 8);
(c) Examination of the portions of high energy lines specified in Technical Specification 4.15. For Surry, Unit 2, this specification applies to welds in the Main Steam and Main Feedwater lines in the Main Steam Valve House; (d) Examinations of the portions of sensitized stainless steel specified in Section B of Technical Specification Table 4.2-1; (e) Ultrasonic examination of Steam Generator Feedwater Nozzles per IE Bulletin 79-13, Cracking in Feedwater System Piping (Reference 9);
(f) Volumetric and surface examination of all low-pressure turbine blades and a volumetric examination of the low-pressure turbine disc bore and keyway every five years as specified in Technical Specification 4.2-1; and (g) Eddy current examination (100%), each refueling outage, of all reactor vessel in-core detector thimble tubes that are in service per IE Bulletin 88-09, Thimble Tube Thinning in Westinghouse Reactors (Reference 10).
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- 3. EVALUATION OF RELIEF REQUESTS The requests for relief from the ASME Code requirements that the licensee has determined to be impractical for the third IO-year inspection interval are evaluated in the following sections.
3.1 Class 1 Components 3.1.1 Reactor Pressure Vessel 3.1.1.1 Request for Relief SR-001, Examination Category B-F, Item BS.IO, Reactor Vessel Nozzle-to-Safe End Butt Welds Code Requirement: Examination Category 8-F, Item BS.IO requires a volumetric and a surface examination of Class 1 nozzle-to-safe end butt welds on 4-inch nominal pipe size or larger, as defined by Figure IWB-2S00-8.
Licensee's Code Relief Request: The licensee requested relief from performing the Code-required surface examinations on the
- following nozzle-to-safe end butt welds:
Weld# Drawing# Class 1-0IDM 11548-WMKS-RC-10-1 I 1-17DM 11S48-WMKS-RC-10-l I 1-0lDM 11S48-WMKS-RC-11-1 I 1-17DM I1S48-WMKS-RC-ll-l I 1-0lDM 1IS48-WMKS-RC-12-l I 1-17DM I1S48-WMKS-RC-l2-1 1 Licensee's Basis for Requesting Relief (as stated}:
"The outside diameter volumetric examination would be extremely difficult to perform. Access to the area is restricted by permanent neutron shielding and support structures. Any planned removal to provide access is made difficult by the relatively small sandplug access on the floor of the refueling cavity. The difficult access restrictions are also complicated by the anticipated high dose level. The general area estimate aroun~
the perimeter of the vessel and nozzle area is 1000 to 2000 MR/HR. The contact estimate ranges from 4000 to 8000 MR/HR in the vicinity of the sliding foot support."
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r
Conclusion:
The licensee's proposed volumetric examination in lieu of the surface examination should provide an acceptable level of quality and safety. Therefore, it is recommended that this alternative examination be authorized as requested, pursuant to 10 CFR 50.55a(a)(3)(i), provided a full-volume examination is performed.
3.1.1.2 Request for Relief SR-007, IWA-2610, Weld Reference System for The Reactor Vessel and Vessel Nozzle Area Code Requirement: Section XI, Paragraph IWA-2610, Weld Reference System - General, requires that a reference system be established for all welds and areas subject to surface or volumetric examinations. Each such weld and area shall be located and identified by a system of reference points. The system shall permit identification of each weld, location of each weld center line, and designation of regular intervals along the length of the weld.
Licensee's Code Relief Request: The licensee requested relief from establishing a weld reference system for the reactor vessel, including the reactor vessel nozzle area.
Licensee's Basis for Requesting Relief (as stated):
"The automated tool establishes its reference point using an existing zero reference in the reactor vessel. This point allows the device to repeat examination locations without the necessity of any other reference systems. It accomplishes this by use of an electronic encoder system which provides for sufficient repeatability."
Licensee's Proposed Alternative Examination (as stated):
"The automated vessel tool examinations will continue to establish it's reference system based upon the existing zero reference. No other system is planned or deemed necessary."
Evaluation: The Code requires a reference system that permits identification of each weld, location of each weld center line, 9
e e that will interrogate the inner radius section at precise angles.
Also, in order to obtain meaningful results, the nozzle material grain structure must be such that an adequate signal-to-noise ratio can be obtained over a long metal path distance.
"Integrally cast.nozzles contain limitations such as an irregular O.D. profile, a rough surface condition, and an attenuating grain structure. The irregular surface condition causes the beam angle to vary from point to point around the nozzle. The attenuating
. grain structure results in a low signal-to-noise ratio at the nozzle inner radius. Limited access to the nozzle as well as the limitations imposed by the material conditions, area dose rates and the ~omplicated nature of the examination technique would make evaluation of any indications very difficult.
"Any examination on this nozzle could only be described as "best effort", and not commensurate with the anticipated exposure to perform this examination. It is estimated that at least 3.675 man-rem would be required to perform this inspection and if the cables to the heater penetrations require removal to provide better access, then greater than 9 man-rem would be required."
In the November 28, 1994, response to the NRC's RAI, the licensee submitted the following additional information:
"A visual (VT-I) examination is considered impractical, since the area in question is covered by a welded retaining basket and the inner radius is partially covered by a thermal sleeve."
Licensee's Proposed Alternative Examination (as stated):
"A visual (VT-2) examination of the pressurizer surge line ~ozzle area will be performed during the normally scheduled pressure test (Class 1) each refueling."
Evaluation: The Code-required volumetric examination of the inner radius section of the pressurizer surge nozzle is impractical since integrally cast nozzles contain limitations such as an irregular 00 profile, a rough surface condition, and an attenuating grain structure. Limited access to the nozzle, as well as limitations imposed by the material conditions, area dose rates, and the complicated nature of the examination technique would make evaluation of any indications very difficult. To perform the Code-required examination, design modifications and/or replacement of the pressurizer would be required.
Therefore, the Code-required examination is impractical for the 11
e e removal of the support ring at the mechanical connection would allow some increase in coverage near the mechanical connection, where the support ring could be spread apart. However, the actual area of weld made accessible to this increased coverage is estimated to be very small in relation to the overall weld length, because the insulation support structure is rigid, interconnected with cross supports, and welded to the supports for the safety valves and power operated relief valves. The intersection of the circumferential shell to head weld and longitudinal welds is physically located behind one of these supports. Examination coverage of this area would not be improved by partial removal at the mechanical connection.
"Any removal of the mechanical connection and spreading apart of the support structure would increase the risk of misalignment problems, and warping of the structure. This risk ctiupled with the marginal increase in examination coverage, makes partial removal of the insulation support structure also impractical."
Licensee's Proposed Alternative Examination (as stated):
"A volumetric examination will be performed to the extent practical on welds 1-07 and 1-02. No extended beam path examinations can be performed, since the pressurizer is a clad vessel."
Evaluation: The subject pressurizer upper head-to-shell weld and associated upper shell longitudinal weld are partially covered by the upper head insulation and valve support assembly. Based on the review of this assembly, it appears that removal of the support ring to provide access for complete volumetric examinatiori would require a major effort and require many man-hours of skilled maintenance personnel, who would potentially undergo significant radiation exposure. Partial removal by spreading the rings at the mechanical connections is possible, but would not increase coverage significantly. Imposing the requirement on the licensee to remove the assembly and perform the volumetric examination to the extent required by the Code is ...
therefore considered impractical. To meet the Code requirement, the assembly would have to be removed, causing a considerable burden on the licensee.
==
Conclusions:==
The licensee is exam1n1ng the pressurizer upper head-to-shell weld and the associated upper shell longitudinal 13
e Also, in order to obtain meaningful results, the nozzle material grain structure must be such that a relativity high signal-to-noise ratio can be obtained over the required metal path_
distance. Additionally, for nozzles with a complex 0. D.
profile, examination personnel need training on the proper placement and manipulation of the search unit.
"Virginia Power has previously assessed the feasibility of performing examinations on the North Anna Unit 2 cast primary nozzle inner radii. Virginia Power performed examinations on a Westinghouse Model 44 channel head which was used to train welders for the North Anna Unit 1 steam generator replacement.
This channel head is made from the same cast material (ASTM 216-WGG) as Model 51 generators which are currently installed in Surry Unit 2. We believe that the general surface profile and acoustic properties are representative of the Surry Unit 2 steam generators.
"Examination Results
- 1. Comparison of Material Noise Figures A and Bon Attachment 12 depict the respective
.responses from notches 4 and 6 from calibration block VPSGINRl. This calibration block was manufactured to examine the North Anna Unit 1 replacement steam generator forged carbon steel primary nozzle inner radii. Both notch responses exhibit a high signal to noise ratio with little evidence of material noise. Figure A on Attachment 2 depicts the material noise from the Model 44 primary nozzle at the same sensitivity level. At this sensitivity level, there is no evidence of clad roll. The first indication of sound penetration (Attachment 1, Figure 8) appeared at 12db above the reference level when evidence of clad roll was detected.
- 2. The O.D. surface of the nozzle had an irregular contour which is typical of large cast products. Due to the surface contour, it was necessary to apply a lot of couplant to maintain contact with the examination surface. The irregular surface and large amount of couplant req~ired caused an apparent change in the sound beam angle from point to point over the examination surface. Therefore, it could
- not be determined where the sound beam was directed with respect to the inner radius.
"Conclusion The Surry Unit 2 steam generator primary nozzle inner radii were not designed for ultrasonic examination from the O.D. The nozzles are integrally cast into the channel head. Therefore, the nozzles contain examination limitations such as an irregular 2
Figures.and Attachments are not included in this report.
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Conclusion:
The Code-required volumetric examination of the steam generator nozzle inside radius sections is impractical to perform at Surry, Unit 2. Considering the examinations that are being performed and the impracticality of meeting the Code requirements, it is recommended that relief be granted pursuant to 10 CFR 50.55a(g)(6)(i), provided that a color system is used for the remote VT-I visual examination of the inside radius sections.
3.1.3.2 Request for Relief SR-010, Examination Category 8-D, Items 83.150 and 83.160, Examination of the Regenerative Heat Exchanger Nozzle-to-Vessel Welds and Nozzle Inside Radius Sections Code Requirement: Section XI, Table IW8-2500-l, Examination Category 8-D, Items 83.15Q and 83.160 require 100% volumetric examination of the regenerative heat exchanger nozzle-to-vessel welds and nozzle inside radius sections as defined by Figure IWB-2500-7.
Licensee's Code Relief Request: The licensee requested relief from performing the Code-required 100% volumetric examination of the following examination areas on Regenerative Heat Exchanger (2-CH-E-3):
Welds/Components Description Class 1-06 nozzle-to-vessel weld I NIR-06 nozzle inside radius 1 1-08 nozzle-to-vessel weld 1 NIR-08 nozzle inside radius 1 1-09 nozzle-to-vessel weld I NIR-09 nozzle inside radius I 1-11 nozzle-to-vessel weld I NIR-11 nozzle inside radius I 1-13 nozzle-to-vessel weld I NIR-13 nozzle inside radius I 1-15 nozzle-to-vessel weld I NIR-15 nozzle.inside radius I 17
e e considerable burden on the licensee. The licensee has proposed as an alternative to perform a liquid penetrant surface examination.* The liquid penetrant examination should provide reasonable assurance of structural integrity.
Conclusions:
The nozzle examination areas listed above are not conducive to a meaningful ultrasonic examination. Therefore, it is recommended that relief be granted as requ~sted, pursuant to 10 CFR 50.55a(g}(6}(i}.
3.1.4 Piping Pressure Boundary 3.1.4.1 Request for Relief SR-008, Examination Category 8-J, Selection Criteria for Examination of Class 1 Piping Welds Code Requirement: Examination Category B-J, Table IWB-2500-1 includes the following notes as requirements in selecting Class 1 piping welds for examination:
"(l} Examinations shall include the following:
(b} All terminal ends and joints in each pipe or branch run connected to other components where the stress levels exceed either of the following limits under loads associated with specific seismic events and operational conditions:
(1} primary plus secondary stress intensity range of 2.4Sm for ferritic steel and austenitic steel (2} cumulative usage factor U of 0.4 11 (2} The initially selected welds shall be reexamined during each inspection interval."
Licensee's Code Relief Request: The licensee requested relief from implementing Code weld selection requirements l(b} and 2 of Examination Category 8-J, Table IWB-2500-1.
Licensee's Basis for Requesting Relief (as stated}:
"The second interval selection was based upon the 1974 Edition with Summer 1975 Addenda (74/S75} of ASME Section XI. As a result, notes l(b} and 2 cannot be applied without some programmatic additions and modifications. In addition, although stress and utilization calculations exist for Surry Unit 2, no 19
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Conclusion:
Stress data for Class 1 piping welds required by the 1989 Edition are not available for weld selection. The licensee's approach to the selection of Class 1 piping welds (potential high stress) has a sound engineering basis and provides an acceptable level of quality and safety. Therefore, it is recommended that the proposed alternative be authorized, pursuant to 10 CFR 50.55a(a)(3)(i).
3.1.5 Pump Pressure Boundary (No requests for relief) 3.1.6 Valve Pressure Boundary (No requests for relief) 3.1.7 General (No requests for relief) 3.2 Class 2 Components 3.2.1 Pressure Vessels (No requests for relief) 3.2.2 Piping {No requests for relief) 3.2.3 Pumps 3.2.3.1 Request for Relief SR-004, Examination Category C-G. Item C6.10, Pump Casing Welds Code Requirement: Examination Category C-G, Item C6.10 requires a 100% surface examination of the Class 2 pump casing welds as defined by Figure IWC-2500-8.
Licensee's Code Relief Request: The licensee requested relief from performing a surface examination on the following pump casing welds in-the outside recirculation spray (RS) and safety injection (SI) pumps:
21
e e The licensee has proposed to perform a VT-1 visual examination of the accessible portions of the inside surfaces of the pump casing welds when a pump is disassembled and the pump shaft removed for maintenance. This will detect significant degradation and, therefore, provide reasonable assurance of operational readiness.
Conclusion:
The surface examination of the subject pump casing welds is impractical to perform at Surry, Unit 2. Therefore, it is recommended that relief be granted as requested, pursuant to 10 CFR 50.55a(g)(6)(i).
3.2.4 Valves (No'requests for relief) 3.2.5 General 3.2.5.1 Request for Relief SR-013, Examination Category C-C, Item C3.10, Integrally Welded Attachments to the Residual Heat Removal Heat Exchangers Code Requirement: ASME Section XI,. Examination Category C-C, Item C3.10 requires a surface examination of integrally welded attachments to Class 2 pressure vessels.
Licensee's-Code Relief Request: The licensee requested relief from the Code-required surface examination of integrally welded attachments to the Residual Heat Removal heat exchangers.
Licensee's Basis for Requesting Relief {as stated}:
"These heat exchangers and integral attachments were designed and constructed to ASME Section VIII, 1965 Edition, Winter 1966 Addendum. This Code limited the examination of the integral attachments to a visual type exam requiring (UW-38} that visible defects, such as cracks, pinholes, and incomplete fusion and defects detected by the hydrostatic test be removed. These fillet weld integral attachments never received nor were they required to receive a surface examination under the Construction Code. Additionally the initial preservice examinations at Surry were limited to Class 1 components, since Class 2 and 3 had not yet been placed into the Code, as such no preservice surface examination was conducted on these integral attachments. The 23
e
Conclusion:
Requiring tne licensee to perform surface examinations on the Residual Heat Removal heat exchangers' integral attachments would result in a hardship or unusual difficulties without an compensating increase in the level of quality and safety. Therefore, it is recommended that the proposed alternative be authorized as requested, pursuant to 10 CFR 50.55a(a)(3)(ii).
3.3 Class 3 Components (No requests for relief) 3.4 Pressure Tests 3.4.1 Class 1 System Pressure Tests 3.4.1.2 Request for Relief 1, IWB-5222, as Modified by Code Case N-498, for Class 1, Residual Heat Removal {RHR) Piping Code Requirement: Table IWB-2500-1, Examination Category 8-P, requires a system hydrostatic test, in accordance with IWB-5222, for Class 1 pressure-retaining piping. Code Case N-498 requires that:
(1) A system leakage test (IWB-5221) be conducted at or near the end of each inspection interval, prior to start-up.
(2) The boundary subject to test pressurization during the system leakage test extends to all Class 1 pressure-retaining components within the system.
(3) Prior to performing the VT-2 visual examination, the system be pressurized to nominal operating pressure for at least 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> for insulated systems and 10 minutes for noninsulated systems.
The system shall be maintained at nominal operating pressure during the performance of the VT-2 visual examination.
Licensee's Code Relief Request: The licensee requested relief from performing the hydrostatic test at the pressure required by 25
3.4.3 Class 3 System Pressure Tests 3.4.3.1 Request for Relief 2, System Hydrostatic Test, IWD-5223, of Circulating and Service Water System Code Requirement: Table IWD-2500-1, Examination Category D-A, requires a system hydrostatic test in accordance with IWD-5223, System Hydrostatic Test, for Class 3 pressure-retaining piping.
Licensee's Code Relief Request: The licensee requested relief from performing the hydrostatic test for the Class 3 Circulating and Service Water System piping upstream of the first isolation valve.
Licensee's Basis for Requesting Relief (as stated):
"The Code addresses the problem of performing hydrostatic tests on open ended portions of discharge lines beyond the last shut-off valve in non-closed systems in IWD-5223(d). A similar problem exists for the intake piping at Surry Unit 2 as it is non-isolatable for the increased pressure requirements of a hydrostatic test."
Licensee's Proposed Alternative Examination (as stated):
"As an alternative, the requirements applied to open ended portions of discharge lines (IWD-5223(d will be applied. In this case confirmation of adequate flow during system operation shall be acceptable in lieu of system hydrostatic test." Evaluation: IWD-5210{a) requires that the pressure-retaining components within the boundary of each system be pressure tested. For open-ended systems, the piping beyond the last discharge valve is exempted from the hydrostatic test requirements. The problems associated with testing are the same for suction piping prior to the first isolation valve as they are for open-ended systems beyond the last discharge valve. The only practical test to verify the operability of that portion of such a system is a fl ow test. 27
/
e Licensee's Proposed Alternative Examination (as stated):
"As an alternative, it is requested that 60 psig be used as this systems PD value."
Evaluation: IWD-5223(a) requires a test pressure of 1.10 times the system pressure for Service Water System hydrostatic tests. The licensee has proposed to use 60 psig as th~ design pressure for the Class 3 Service Water System piping and components shown on prints 11448-CBM-0718-3 and 11448-CBM-071D-3. The licensee has pointed out that using a design pressure (PD) of 100 psig would be excessive for the piping and components being pressure tested in the Service Water System. The licensee's proposed alternative pressure of 60 psig for the system PD value is based on maximum design pressures associated with non-isolable interconnected piping and components. The licensee's proposed design pressure of 60 psig should be sufficient to test the subject system.
Conclusion:
The proposed test pressure will provide an acceptable level of quality and safety. Therefore, it is recommended that the proposed alternative be authorized, pursuant to 10 CFR 50.55a(a)(3)(i). 3.4.3.3 Request for Relief 4, IWD-5223, System Hydrostatic Test of Class 3-Auxiliary Feedwater {AFW) Code Requirement: Table IWD-5223(a) requires a system hydrostatic test pressure of at least 1.10 times the system pressure, Pav, for systems with design temperatures of 200°F or less, and at least 1.25 times the system pressure, Psv' for systems with design temperatures above 200°F. Licensee's Code Relief Request: The licensee requested relief from performing the hydrostatic test at the pressure required by Table IWD-2500-1 for the Class 3 Auxiliary Feedwater (AFW) piping 29
"The basis for relief then is two-fold. The first impracticality is the overpressurization of piping and components downstream of the pressure reducing orifice and the design pressure class rating change. The second impracticality is the incorporation of the auxiliary feedwater pumps into the test boundary due to the lack of vent, drain, and manual isolation valves."
- Licensee's Proposed Alternative Examination (as stated):
"The identified components will be tested in accordance with IWD-5222, Functional Test Requirements, in conjunction with the associated auxiliary feedwater pump at normal operating pressure." Evaluation: The Code requires a system hydrostatic test for the subject Class 3 lines. However, because of the difference in design pressures and the configuration of the valves, the Code-required test pressure cannot be achieved without over pressurizing the piping downstream. Therefore, the Code requirement is impractical. Imposition of the requirement would. necessitate design modifications to adequately isolate the high-pressure portions of the system. This would represent a considerable burden on the licensee. In lieu of the hydrostatic test, the licensee will perform a functional test at normal operating pressure that should provide reasonable assurance of operational readiness. The subject portions of the AFW system are redundant loops fabricated from I-inch diameter piping. Consequently, if a leak occurred, the volume would be small, due to the pipe size, and this leakage should be detected during the system functional test. In addition, the impact of a potential leak on the AFW system would be reduced by system redundancy.
== Conclusion:== Based on the factors presented in the evaluation, reasonable assurance of operational readiness will be provided by the licensee's proposed examination. Therefore, it is recommended that relief be granted pursuant to 10 CFR 50.55a(g)(6)(i). 31
e bolting in the connection shall be removed and visually (VT-3) examined and evaluated to the Code requirements. The limitation of selecting only one bolt initially is the same as the Code requirements found in the 1992 Edition of ASME Section XI, IWA-5250(a)(2). Bolting removal, however would be limited to bolting material affected by boric acid wastage, such that visual (VT-3) examination would identify this condition .. "Additionally for bolting subject to boric acid wastage examined during pressure tests conducted just prior to start up (Class 1
- system leakage~.Class 1 hydrostatic, Class 2 pressure test scheduled in association with the Class 1 tests, and Code Case N-498 tests) in subatmospheric conditions, leakage identified near bolted connections shall be evaluated for removal need based upon the extent of leakage, correction requirements, and previous examination* history associated with commitment or any other examinations conducted during that refueling outage.
This evaluation shall be subject to the review of the Authorized Nuclear Inservice Inspector (ANII)." Evaluation: In accordance with the 1989 Edition of the Code, when leakage occurs at bolted connections, all bolting is required to be removed for VT-3 visual examination. The licensee's proposed alternative is to evaluate the bolted connection. The licensee's alternative to the Code requirement could potentially eliminate the removal and VT-3 visual examination of bolting at leaking bolted connections. Recent inGidents of degraded bolting have reinforced the reasons for removing and evaluating at least one bolt at a leaking bolted connection as part of the* corrective action. Because degradation rates cannot be reliably predicted and bolting material records may not be accurate, th~ removal of a bolt for evaluation and immediate corrective action when leakage occurs at any bolted connection, regardless of material, is warranted (Reference 11). It is reasonable to conclude that degradation, if present, would be detected provided that the licensee removes at least one bolt nearest the source of leakage for VT-3 visual examination. The licensee's alternative, in combination with the removal and VT-3 visual examination of at least one bolt closest to the source of 33
e the insulation. The test will be held at nominal operating pressure for four hours for insulated systems and ten minutes for noninsulated system prior to performing the visual VT-2 examination." Evaluation: Paragraph IWA-5242(a) requires the removal of insulation from pressure-retaining bolted connections in borated systems for direct VT-2 visual examination during system pressure testing. The licensee has stated that the requirement to remove insulation from bolted connections in such systems to perform a VT-2 visual examination under high temperature sub-atmospheric conditions results in an unusual hardship. Using the provision of IWA-5245 that allows cooldown of the systems to a temperature corresponding to 200°F prior to visual examination subjects the systems to unnecessary cycles and extended outages. The INEL staff has determined that imposing the above mentioned Code requirement is a hardship for Surry, Unit 2, that does not provide a compensating increase in the level of quality and safety. The licensee's proposed .alternative consists of performing a VT-2 visual examination at zero or static pressure with insulation removed and the Code-required testing without removing the insulation. These tests will be performed once each refueling outage for Cl ass 1 piping* and each peri ad for Cl ass 2 piping. The Code-required test will include a four-hour hold time for insulated systems and a ten minute hold for noninsulated system prior to performing the VT-2 visual examination. These alternative examinations should provide reasonable assurance of continued structural integrity.
== Conclusion:== Imposing the Code requirement to remove insulation from bolted connections in systems borated for the purpose of controlling reactivity to perform a VT-2 visual examination results _in a hardship without a compensating increase in the level of quality and safety. The licensee's propo~ed alternative should provide reasonable assurance of operational readiness. 35
e "Meet1ng the above new ASME Section XI requirements would require the fabrication of new calibration blocks. "Satisfactory ultrasonic system calibration can be performed with the existing calibration blocks. Use of the existing calibration blocks also allows correlation of ultrasonic data from previous interval examinations as required by IWA-1400(h). The location of the notches in the piping calibration blocks provides adequate signal separation for sweep calibration. Distance-amplitude calibration down to the clad-to-base metal interface, as delineated by Nonmandatory Appendix B to Section V, Article 4*, can be performed from the unclad portion of the clad side of the existing vessel calibration block." Licensee's Proposed Alternative Examination (as stated): "It is proposed that the existing calibration blocks be used during the third inspection interval." Evaluation: Section XI, Appendix III-3430 requires the calibration blocks to generally conform to the design layout shown in Figure III-3230-2. However, Appendix III-3430 also states "Alternate block design and layout may be used, provided similar beam paths are utilized." The calibration blocks meet this requirement and, therefore, relief is not required for those calibration blocks that deviate from Figure III-3230-2. Section V, Article IV, Paragraph T-441.1.2.2 requires the block to be clad to the component clad nominal thickness. The subject calibration blocks are partially clad instead of fully clad as shown by Figure T-441.1. The portions of the calibration blocks that contain the calibration reflectors are clad. Since the calibration is performed in an area that is clad, the calibration block meets the intent of the Code requirement. In addition, the existing blocks have proven satisfactory for performing calibrations for previous examinations. Continued use of the subject calibration blocks will provide results consistent with those of previous examinations. Any increase in plant safety that might occur with new blocks ~ould not compensate for the burden placed on the licensee to fabricate new calibration blocks to satisfy the current Code requirements. 37
"Code Case N-524 provides an acceptable level of safety and quality by concentrating the examination in the high risk location associated with the intersection of the circumferential and longitudinal weld in piping. Additionally the Code cas~
eliminates the portion of the current Code examination volume requirements beyond the intersection area. This area is perceived by the ASME Code as being relatively low risk. Continued examination of this area would significantly increase the exposure of examination personnel with a minimal increase to safety." Licensee's Proposed Alternative Examination {as stated):
"The requirements of Code Case N-524, Alternative Examination Requirements for Longitudinal Welds in Class 1 and 2 Piping Section XI Division 1, shall be followed."
Evaluation: The licensee requested relief from performing the surface and volumetric examinations, as applicable, of the longitudinal welds in Class 1 and Class 2 piping to the extent required by the Code. The licensee's proposed alternative is to follow ASME Code Case N-524, which requires surface and volumetric examination, as applicable, of the longitudinal weld in conjunction with the circumferential weld examination; volumetric examinations of circumferential welds include both transverse and parallel* scans. As a result, the length of longitudinal weld that falls within the circumferential weld examination area will be examined. The examination records for the circumferential weld examinations will be used to document the extent of longitudinal weld examined. Code Case N-524 is based on the position that longitudinal welds are unlikely to fail; this is the result of fabrication controls and non-susceptibility to conditions that lead to failure. The potentially critical portion of the longitudinal welds {i.e., the portion that intersects the circumferential weld) will be examined in conjunction with the circumferential welds. 39
e "In addition at the time welds are examined volumetrically for program requirements, a reference will be established for each weld, indicating a zero point and direction of examination. Welds which contain recordable indications (RI) shall be marked to ensure location of the indication, using appropriate reference marks. This reference system and marks will be permanently fixed on the weld." Evaluation: For an operating plant, establishing a weld reference system for all welds and areas subject to surface or volumetric examination is a major effort and, in some cases, is prohibitive due to inaccessibility and/or high radiation levels. In order to establish a weld reference system for all welds and areas subject to surface and volumetric examinations in accordance with the requirements, many man-hours and man-rem of radiatio~ exposure would be required to perform such tasks as locating the welds, removing insulation, marking the welds, and reinstalling insulation, regardless of whether or not the weld is scheduled for examination. Therefore, the Code requirement for establishing a weld reference system for all welds subject to examination, even if they are not being examined at that time, is impractical for an operating plant. Imposition of the requirement on Virginia Ele~tric Power Company would cause a burden. The licensee has committed to perform all required reference marking with each piping weld examination. Impracticality will not exist for these welds since access will have been provided to perform examinations.
== Conclusion:== Marking all welds and areas subject to surface or volumetric examination, as required by the Code, in the absence of inspection is impractical at Surry, Unit 2, since it is an operating plant. However, as each Class 1 and 2 piping system is examined, access for marking each weld will be provided and impracticality for that particular weld will not exist. Therefore, to provide assurance of traceability of piping welds and repeatability of examinations, it is recommended that relief be granted pursuant to 10 CFR 50.55a(g)(6)(i), provided that each 41
e Licensee's Proposed Alternative Examination (as stated): "Code Case N-509 will be used in its entirety. Code Case references to the 90 addendum of ASME Section XI are the same as the provisions in Code Case N-491, which has been implemented by our support program." Evaluation: The licensee proposes, as an alternative to the Code requirements, to apply the requirements of Code Case N-509 for the examination of integral attachments on Code Class 1, 2~ and 3 piping and components. Code Case N-509 provides an alternative to the examination of Class 1, 2, and 3 integral attachments. However, due to the ambiguity of notes in the examination table, if component supports were selected that did not contain any welded attachments then no welded attachments would be required to be inspected. The INEL staff believes that this is an editorial mistake and that Cope Case N-509 is acceptable provided that the licensee schedules a minimum of 10% of integral attachments in all Code Class 1, 2, and 3 systems.
== Conclusion:== The licensee's proposed alternative for the examination of integral attachments will provide an acceptable level of quality and safety. Therefore, it is recommended that the licensee's proposed alternative be authorized, pursuant to 10 CFR 50.55a(a)(3)(i), provided that at least a 10% sample of all Code Class 1, 2, and 3 integral attachments is examined.
~-
43
requirements probably could not be achieved. Therefore, it is concluded that the public interest is not served by imposing certain provisions of Section XI of the ASME Code that have been determined to be impractical. The licensee should continue to monitor the development of new or improved examination techniques. As improvements in these areas are achieved, the licensee should incorporate these techniques in the ISI program plan examination requirements. Based on the review of the Surry Power Station, Unit 2,- Third 10-Year Interval Inservice Inspection Program Plan, Revision 0, the licensee's response to the NRC's request for additional information, and the recommendations for granting relief from the ISI examinations that cannot be performed to the extent required by Section XI of the ASME Code, no deviations from regulatory requirements or commitments were identified. 45
1,.-...
* -5. REFERENCES e
- 1. Code of Federal Regulations, Title 10, Part 50.
- 2. American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, Division 1:
1989 Edition
- 3. Surry Power Station, Unit 2, Third JO-Year Interval lnservice Inspection Program Plan, Revision 0, submitted March 18, 1994.
- 4. NUREG-0800, Standard Review Plans, Section 5.2.4, "Reactor Coolant Boundary Inservice Inspection and Testing," and Section 6.6, "Inservice Inspection of Class 2 and 3 Components, July 1981.
11
- 5. Letter, dated October 20, 1994, B. C. Buckley (NRC) to J. P. O'Hanlon (Virginia Electric and Power Company) containing request for additional information on the Surry Power Station, Unit 2, Third JO-Year Interval lnservice Inspection Program Plan.
- 6. Letter, dated November 28, 1994, J. P. O'Hanlon (Virginia Electric and Power Company) to Document Control Desk (NRC) containing the response to the NRC's request for additional information.
- 7. NRC Regulatory Guide 1.150, Ultrasonic Testing of Reactor Vessel Welds During Preservice and lnservice Examinations, Revision 1, February 1983.
- 8. NRC Regulatory Guide 1.14, Reactor Coolant Pump Flywheel Integrity, Revision 1, August 1975.
- 9. IE Bulletin 79-13, Cracking in Feedwater System Piping, August 30, 1979.
- 10. IE Bulletin 88-09, Thimble Tube Thinning in Westinghouse Reactors, July 26, 1988.
11 .. NRC Event Number 26899, "Degraded Condition of Bolting During Operation," March 1994. NRC Event Number 26992, "Degraded/Unanalyzed Condition of Bolting," March 1994. 46
NA:,; c,j;,._, 335 U.S. NUCLEAR REGULATORY COMMISSION ;, :;epc~- \_ '."::= , :.391 !AniQned bv ~RC. Add Vol.. Succ .. Re..-., NPC:,1 11C2. 1nd Addendum Numoers. if '""., 3201, :202 BIBLIOGRAPHIC DATA SHEET
/See insrrucrions on rhe revers~/
- 2. TITL,f AND SUBTl"J;LE , , INEL-94/0280 1ecnnica1 Evaluation Report on the Third 10-Year Interval Inservice Inspection Program Plan: 3. 'uATE RE?OAT PL:3~:S'-ED Virginia Electric and Power Company, Surry Power Stat-ion, Unit 2 MONTH May i 199:s" Docket Number 50-281 4. FIN OR GRANT NUI/SE.i FIN-L2556 (T0-46)
- 5. AUTHOR ISi 6. TYPE OF REPORT Technical B. W. Brown, E. J. Feige, 7. PERIOD COVERED 11nclus,ve O,:c,.
K. W. Hall, A. M. Porter
- 8. PER FORMING ORGANIZATION - NAME AND ADDA ESS Ill NRC, provid* Division, Office or Rogian, U.S. Nuclo~r R*gularory Commission, *nd m*iling *ddms: ii conrracror. orov,ae nwne *nd m*iling MJtJ~ss.)
LITCO P.O. Box 1625 Idaho Falls, ID 83415-2209
- 9. SPONSORING ORGANIZATION - NAME AND ADDRESS/// NRC, rypo "Same** *bo~";il conrracror. provido NRC Division, Offico or Rogian, U.S. NuclHr R*gutarory Comm1s,1on.
and m*iling *ddmu..J Civil Eng. and Geosciences Branch Office of Nuclear Regulatory Commission U.S. Nuclear Regulatory Commission Washington, D.C. 20555
- 10. SUPPLEMENTARY NOTES
- 11. ABSTRACT /200 words or 1oss1 This report presents the results of the evaluation of the Surry Power Station, Unit 2, Third JO-Year Interval Inservice Inspection (ISI) Program Plan, submitted I March 18, 1994, including the requests for relief from the American Society of I Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Section XI requirements
- I that the licensee has determined to be impractical. The Surry Power Station, Unit 2, Third JO-Year* Interval ISI Program Plan is evaluated in Section 2 of this report:
The ISI Program Plan is evaluated for (a) compliance with the appropriate edition/addenda of Section XI, (b) acceptability of examination sample, (c) correctness of the application of system or component examination exclusion criteria, and (d) compliance with !SI-related commitments identified during previous Nuclear Regulatory Commission (NRC) reviews. The requests for relief are evaluated in Section 3 of this report.
- 12. KEY WORDSiDESCR I PTO RS /Lisr words or phra,.s m*r will *,sisrr.,o,rr:h*n: in locating rh* ,..Port. I 13. AVAIL.AiSIL.ii'Y STATEMENT Unlimited
- 14. SECURITY ClASS1**CATIO",
/This Pog*I Unclassified (Tl'lls Rtoorr, Unclassified
- 15. NUMBER OF PAGES
- 16. PRICE NAC FOAM JJ!i 12-l!91
SURRY POWER STATION, UNIT 2 Page 1 of 4 Third IO-Year ISI Interval TABLE 1
SUMMARY
OF RELIEF REQUESTS SR-001 Reactor B-F 85.10 Nozzle-to-Safe End Butt Welds Surface and Automated 100% Authorized Vessel volumetric volumetric exam from the examination pipe ID surface SR-002 Steam B-D 83.140 Nozzle Inside Radius Section Volumetric Visual (VT-1) Granted Generator examination examination from the (Primary nozzle ID Side) SR-003 Pressurizer B-D 83.120 Nozzle Inside Radius Section Volumetric Granted examination SR-004 Recirc. C-G C6.10 Pump Casing Welds Surface examination Visual (VT-1) Granted Spray and examination if pump is Safety disassembled and shaft Injection .removed for maintenance Pumps SR-005 Ultrasonic Calibration block fabrication Section XI, Use existing calibration Authorized Calibration requirements Appendix III and blocks Block Section V, Article IV SR-006 A11 Class 1 Weld reference system Weld reference Establish weld reference Granted w/ and Class 2 system per system as welds are conditions Paragraph IWA-2610 examined
r SURRY POWER STATION, UNIT 2 Page 2 of 4 Third 10-Year ISi Interval TABLE 1
SUMMARY
OF RELIEF REQUESTS SR-007 SR-008 Reactor Vessel and Vessel Nozzle Area Class 1 Weld reference system Weld reference system per Paragraph IWA-2610 To use the reference established by the automated tool Authorized B-J B-J Weld selection Table IWB-2500-1 25%, including all Authorized Piping Category B-J Notes typical high stress areas SR-009 Integrally Selection and examination of Surface Code Case N-509, Authorized w/ Welded Class 1, 2, and 3 integrally "Alternate Rules for the- conditions Attachments welded attachments Selection and Examination of Class 1. 2, and 3 Integrally Welded Attachments, Section XI, Division 1". SR-010 Regen Heat B-D B3 .150 Nozzle-to-Vessel Welds Volumetric Surface examination Granted Exchanger B3 .160 Nozzle inner radius sections examination* SR-011 Pressurizer B-B B2. ll Head-to-Shell Weld Volumetric Best effort volumetric Granted 82.12 longitudinal Weld examination examination SR-012 Class 1 and 8-J 89 .12 longitudinal Welds Volumetric and/or Code Case N-524 Authorized 2 piping C-F-1 CS.12 Surface examination C-F-2 CS.22 of at least 12" for CS.42 Class 1 and at CS.52 least 2. ST for CS.62 Class 2 piping CS.82 welds
SURRY POWER STATION, UNIT 2 Page 3 of 4 Third 10-Year ISi Interval TABLE 1
SUMMARY
OF RELIEF REQUESTS
*.* *RNeumbq~eesrt.......
liet1 jt . . . . . s.****yJt.*.**. en.>
.._*. .*. . * .*.*.o_Ir_
*. *.**.**.r_**.********* f< \ ?/
~J<#i \
C~on~nt.**. *. . Cii,teg~fY. SR-013 Residual c-c C3 .10 Integrally welded attachments Surface examination Visual (VT-3) Authorized Heat examination Removal Heat Exchangers RR 1 Class 1 B-P B15.51 Class 1 piping between MOV-2700 System hydrostatic System pressure test Granted Residual and MOV-2701 test in accordance conducted with the Heat with IWB-5222 normal Class 2 N-49B Removal pressure test at the pressure required by the adjoining Class 2 system RR 2 Class 3 Piping upstream of the first System hydrostatic System flow test as Authorized Circulating isolation valve test in accordance allowed in the and Service with IWD-5223 requirements applied to Water open ended portions of discharge lines (IWD-RR 3 Class 3 Class 3 Service Water System System hydrostatic 5223(d)) System hydrostatic test Authorized e Service piping used in the cooling of test in accordance using 60 psig as this Water component cooling water for the with IWD-5223 systems PD value charging pumps and lube oil for the charging pumps
SURRY POWER STATION, UNIT 2 Page 4 of 4 Third IO-Year ISi Interval TABLE 1
SUMMARY
OF RELIEF REQUESTS RR 4 Class 3 Auxiliary Class 3 portions of the Auxiliary Feedwater system between the System hydrostatic test in accordance System functional test IWD-5222 Granted e Feedwater following valves: with IWD-5223 2-FW-145 2-FW-149 2-FW-145 2-FW-629 2-FW-160 2-FW-164 2-FW-161 2-FW-628 2-FW-175 2-FW-179 2-FW-176 2-FW-627 RR 5 Bolted Corrective actions for leakage at IWA-5250(a)(2) 1992 Edition of ASME Authorized w/ Connections bolted connections found during Section XI, conditions pressure test IWA-5250(a)(2) RR 6 Insulated Insulated bolted connections IWA-5242(a) Inspected during outage Authorized Bolted with insulation removed Connections and no pressure requirements}}