ML20212L088
| ML20212L088 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 10/04/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20212L081 | List: |
| References | |
| NUDOCS 9910070153 | |
| Download: ML20212L088 (12) | |
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h UNITED STATES NUCLEAR REGULATORY COMMISSION 7*
WASHINGTON, D.C. 20665-4001
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION L
RELATED TO THE IMPLEMENTATION OF SUBSECTIONS IWE AND IWL l
OF ASME SECTION XI FOR CONTAINMENT INSPECTION -
L REQUESTS FOR RELIEF FLORIDA POWER CORPORATION CRYSTAL RIVER UNIT 3 DOCKET NO. 50-302
1.0 INTRODUCTION
l Pursuant to 10 CFR 50.55a(b) and (g), inservice inspection (ISI) of containment must meet the requirements of the 1992 Edition,1992 Addenda of American Society of Mechanical Engineers (ASME) Code,Section XI, Subsections IWE and IWL. Subsections IWE and IWL provide the requirements for ISI of Class CC (concrete containments), and Class MC (metallic containments) of light-water cooled power plants. Pursuant to Title 10, Code of Federal Reaulations (10 CFR) Section 50.55a(g)(6)(ii)(B), the first period containment examinations j
must be completed by September 9,2001. Altematives to the requirements of 10 CFR l
50.55a(g) may be authorized pursuant to 10 CFR 50.55a(a)(3), if (i) the proposed altemative provides an acceptable level of quality and safety, or (ii) compliance with the specific i
requirement'of the Code would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
By letter dated November 30,1998, the licensee, Florida Power Corporation (FPC), submitted Relief Request Nos.98-012 to 98-018, seeking relief from some of the ASME Code Section XI, Subsection IWE requirements for Crystal River L'oi; 3 (CR-3).
2.0 EVALUATION OF RELIEF REQUESTS 2.1 Relief Reauest No. 98-012-11 2.1.1 Code Reauirement Table IWE-2500-1, Examination Category E-D (Item Nos. E5.10 and E5.20) requires a VT-3 visual examination of seals and gaskets during the inspection interval. Seals and gaskets are to be examined for wear, damage, erosion, tears, surface cracks, or other defects that may violate the leak-tight integrity. Defective items are to be repaired or replaced.
i ENCLOSURE 9910070153 991004 F
PDR ADOCK 05000302 P
., 2.1.2 Code Reauirement From Which Relief is Reauested (as stated)
Relief is requested from performing the Code-required visual examination, VT-3, on the above identifient metal containment seals and geskets.
2.1.3 Basis for Relief (as stated)
Seals and gaskets, subject to examination per the ASME Section XI Code, are those used on penetrations (e.g. airlocks, hatches, etc.) which are required to assure containment leak tight j
integrity. As required by 10 CFR Part 50, Appendix J, these same seals and gaskets are i
required to be leak-rate tested (e.g., Type B test). The purposa of the Type B test is to detect local leaks at containment design pressure and to measure leakage across the leakage limiting I
. boundary of containment penetrations whose design incorporates resilient seals, gaskets, sealing compounds, and electrical penetrations fitted with flexible metal seal assemblies.
When compared to a visual examination, a leak rate test is considered a superior and proven method for detecting degradation that may cause containment leakage. If excessive leakage is detected during the test, then corrective actions would be taken and the connection re-tested. The performance of a visual examination will not provide any additional increase in j
quality and safety.
For those penetrations (e.g., equipment hatch, etc.) that are routinely disassembled during a refueling outage, a Type B test is required upon final re-assembly and prior to start-up. The mechanical connection associated with these penetrations employ a tongue and groove or ring joint configuration. Thus, the seals or gaskets are not accessible for examination when the connection is assembled. For this reason, a VT-3 examination of the seal or gasket would have to be' performed prior to final assembly. Since the potential damage to the seal or gasket would most likely occur during the final assembly of the connection, the visual examination provides no compensating increase in quality or safety. Any damage to the seal or gasket that may have occurred which affected the leak-tightness of the containment would be identified during the Type B test.
i Performance of the visual examination of the seals or gaskets would require disassembly and re-assembly of the mechanical connection for those penetrations (e.g., personnel airlock, etc.)
that are not routinely disassembled during a refueling outage. The seals or gaskets
. associated with these penetrations are not accessible for examination when the connection is assembled For this reason, the connection would require disassembly for the sole purpose of performing the visual examination. Since these connections are periodically Type B tested to
. verify their leak-tight integrity, the hardships of performing an additional as-found Type B test, performing disassembly and re-assembly activities, and the increase of the component l
damage probability has been dete; mined to be unwarrantec' ar.*>e%d e cur,ponsating l
increase in quality and safety.
Seals and gr.skets are not part of the containment pressure boundary under current Code rules (NE-1220(b)). When the airlocks and hatches containing these materials are tested in
- accordance with 10 CFR Part 50, Appendix J, degradation of the seal or gasket material would be revealed by an increase in the leakage rate.' Corrective measures would be applied and the component re-tested.' Repair or replacement of seats and gaskets is not subject to Code e
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- (1992, Edition,1992 Addenda) rules in accordance with Paragraph IWA-4111(b)(5) of ASME i
Section XI.
The visual examination of seals and gaskets in accordance with IWE-2500, Table IWE-2500-1 is an increased burden without a compensating increase in quality or safety.
Relief is requested in accordance with 10 CFR 50.55a(a)(3)(ii). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Testing the seats and gaskets in accordance with 10 CFR Part 50, Appendix J will provide adequate assurance of the leak-tight integrity of the seals and gaskets.
The requirement to examine seals and gsskets has been removed in the re-write of the ASME Code,Section XI, Subsection IWE, which has been approved by ASME and published in the
' 1998 Edition.
2.1.4 Altemative Examination (as stated)
The leak-tightness of seals and gaskets will be tested in accordance with 10 CFR Part 50, Appendix J. The 10 CFR Part 50, Appendix J, Type B testing is performed at least once each inspection interval.
2.1.5 Staff Evaluation The licensee proposes to use the existing 10 CFR Part 50, Appendix J, Type B testing as a verification of seal and gasket integrity, rather than disassembling the subject components for the sole purpose of examination.
Performing the VT-3 examinations on the subject gaskets and seals would require disassembly and re-assembly of the mechanical connection for those penetrations that are not routinely disassembled during a refueling outage. The ASME Main Committee and the Board of Nuclear Codes and Standards have also determined that a VT-3 examination of the seals and gaskets is no longer warranted. Both organizations have approved the re-write of Subsection IWE to delete the requirement for performing a VT-3 examination of the seals and gaskets.
This re-write of Subsection IWE was published in the 1998 Edition of the ASME Code,Section XI. Requiring the licensee to disassemble components for the sole purpose of inspecting seals and gaskets would place a significant hardship on the licensee without a compensating increase in quality and safety.
The licensee will verify the leak-tight integrity of seals and gaskets, utilized on penetrations, that are required to assure containment leak-tight integrity, in accordance with the applicable requirements of 10 CFR Part 50, Appendix J. Therefore, the proposed attemative is authorized pursuant to 10 CFR 50.55a(a)(3)(ii) on the basis that compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The proposed testing provides reasonable assurance of containment leak-tight integrity.
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4 2.2 Relief Reauest No. 98-013-Il l.
2.2.1 Code Reauirement Subarticle IWA-2300, " Qualification of Nondestructive Examination Personnel," requires
' qualification of nondestructive examination (NDE) personnel to CP-189 - 1991, " Standard for a
Qualification and Certification of Nondestructive Testing Personnel," as amended by the ASME Section XI.-
2.2.2 Code Reauirements From Which Relief is Reauested (as stated) l Relief is requested from the provisions of Paragraph IWA-2300, " Qualification of nondestructive Examination Personnel,"in accordance with CP-189, as amended by ASME Section XI.
2.2.3 Basis for Relief (as stated)
A written practice based on the requirements of CP-189, to implement Subsection IWE, duplicates efforts already in place for the CR-3 Third Ten Year Inservice inspection Program, which meets the requirements established in ASME Section XI,1989 Edition, no Addenda.
Personnel qualifications are currently based on SNT-TC-1 A, " Personnel Qualification and Certification in Nondestructive Testing," as amended by the requirements of ASME Section XI.
Additionally Subarticle IWA-2300 of ASME Section XI,1992 Edition,1992 Addenda, states,
" Certifications based on SNT-TC-1 A are valid until re-certification is required."
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' Visual examination is the primary NDE method required by Subsection IWE. The requirement established in SNT-TC-1 A for personnel certifications are similar to the requirements described i
in'CP-189. Therefore, use of CP-189 in place of SNT-TC-1 A will not improve the capability of examination personnel to perform the visual and ultrasonic thickness examinations required by
. lWE. -
Development and administration of a second program would not enhance safety or quality and would serve as a burden, particular1y in developing a second written practice, tracking of
' certifications, and duplication of paperwork. The current personnel certification program meets the requirements of ASME Code,Section XI,1989 edition.. Updating the personnel certification program to meet the requirements of ASME Code Section XI,1992 Edition and CP-189 would require a similar request for relief.
Relief is requested in accordance with 10 CFR 50.55a(a)(3)(ii). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a
- compensating increase in the level of quality and safety.
L 2.2.4 Alternative Examination (as stated)
Personnel qualified and certified to a written practice based on SNT-TC-1A and ASME g
l Section XI,1989 Edition, No Addenda, shall conduct examinations required by Subsection IWE. Visual examination personnel will receive specific training in conducting containment examinations.
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3 2.2.5 Staff Evaluation The current FPC program for qualifying and certifying NDE personnel is based on the 1989 Edition of the ASME Section XI requirements for Class 1,2, and 3 components. The 1989 Edition of the Code requires the use of SNT-TC-1 A for the qualification and certification of NDE personnel. Thus, the staff recognizes that the licensee would have to develop a second program for qualifying and certifying its NDE personnel for containment inspection in accordance with Subarticle IWA-2300 of the 1992 Edition of the Code.
As noted by the licensee, visual examination is the primary NDE method required by Subsection IWE. The requirement established in SNT-TC-1A for personnel certifications are similar to the requirements described in CP-189. Therefore, use of CP-189 in place of SNT-TC-1 A will not improve the capability of examination personnel to perform the visual and ultrasonic thickness examinations required by IWE.
Thus, the staff concludes that the imposition of the requirement of Subarticle IWA-2300 (1992 Edition) for containment inspection will subject the licensee to hardship without a compensating increase in the level of quality anti safety. The staff concludes that the licensee's proposed attemative is authorized pursuant to 10 CFR 50.55a(a)(3)(ii) on the basis that compliance with the specified requirements would result in hardship or unusual difficulty without a comperuating increase in the level of quality and safety.
2.3 Relief Reauest No. 98-014-11 2.3.1 Code Reauirement IWE-2200(g) requires that when paint or coatings are re-applied, the condition of the new paint or coating will be documented in the preservice examination records.
2.3.2 Basis for Relief (as stated)
The quality of property applied coatings is important to assure degradation of the liner does not occur, but neither paint nor coatings contribute to the structural integrity or leak tightness of the containment. The paint and coatings on the containment pressure boundary were not subject to Code rules when they were originally applied and are not subject to ASME Section XI rules for repair or replacement in accordance with IWA-4111(b)(5). The adequacy of applied coatings is verified through the inspections performed by the CR-3 Painting Program.
The Painting Program at CR-3 ansures that all protective coatings used for Service Level 1 coatings are proper coatings, applied by qualified personnel and in accordance with manufacturers' instructions, and are inspected and properly documented. The CR-3 Painting Program meets the intent of Regulatory Guide 1.54, Revision O.
Recording the condition of re-applied coating in the preservice record does not substantiate the containment structuralintegrity. Deterioration of the coating in the reapplied ana would require additional evaluation regardless of the preservice record. Recording the condition of new paint or coating in the preservice records does not increase the level of quality and safety of the containment.
4 In SECY'96-080, " Issuance of Final Amendment to 10 CFR Section 50.65a to incorporate by Reference the ASME Boiler and Pressure Vessel Code (ASME Code),Section XI, Division 1, Subsection IWE and IWL," dated April 17,1996, response to Comment 3.2 about IWE-2200(g) states, "In the NRC's opinion, this does not mean that a visual examination must be performed with every application of paint or coating. A visual examination of the topcoat to determine the
'~ soundness and the condition of the topcoat should be sufficient." This is currently accomplished through the inspections performed by the CR-3 Painting Program.
- Relief is requested in accordance with 10 CFR 50.55a(a)(3)(i). The CR-3 Painting Program
~ currently provides an adequate level of quality and safety.
The requirement to perform a preservice examination when paint or coatings are re-applied has been removed in the re-write of the ASME Code,Section XI, Subsection IWE, which has been approved by ASME and published in the 1998 Edition.
2.3.3 Altemative Examination (as stated)
Reapplied paint and coatings on the containment vessel will be examined in accorciance with the CR-3 Painting Program. Although repairs to paint or coatings are not subject to the repair / replacement rules of ASME XI (Inquiry 97-22), repairs to the primary containment boundary, if required, would be conducted in accordance with ASME Section XI Code rules.
2.3.4 Staff Evaluation In the basis for the relief request, the licensee states that the Painting Program at CR-3 ensures that all protective coatings used for Service Level 1 coatings are (1) proper coatings,
. (2) applied by qualified personnel in accordance with the manufacturers' instructions, (3) inspected, and (4) properly' documented. In addition, the Painting Program at CR-3 is
' written to comply with the applicable requirements of Regulatory Guide 1.54. The licensee's l
Painting Program provides a conservative approach to the inspection and documentation of new coatings and as such, the staff concludes that the proposed attemative provides an j
acceptable level of quality and safety. Therefore, the licensee's proposed altemative is authorized pursuant to 10 CFR 50.55a(a)(3)(i).
2.4 Relief Reauest No. 98-015-11 2.4.1. Code Reauirement i
IWE-2500(b) requires that when paint or coatings are to be removed, the paint or coatings shall be visually examined in accordance with Table IWE-2500-1 prior to removal.
2.4.2 Basis for Relief (as stated)
- The interiors of containments are painted to prevent rusting. Neither paint nor coatings contribute to the structuralintegrity or leak tightness of the containment. The paint and
. coatings on the containment pressure boundary were not subject to Code rules when they were originally applied and are not subject to ASME Section XI rules for repair or replacement in accordance with IWA-4111(b)(5). Degradation or discoloration of the paint or coating
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, materials on containment would be an indicator of potential degradation of the containment liner. Additional measures would have to be employed to determine the nature and extent of any degradat!on, if present. The application of ASME Section XI rules for removal of paint or coatings, when unrelated to an ASME Section XI repair or replacement activity, is a burden without a compensating increase in quality or safety.
The Painting Program at CR-3 ansures that all protective coatings used for Service Level 1 coatings are proper coatings, applied by qualified personnel and in accordance with manufacturers' instructions, and are inspected and properly documented. The CR-3 Painting Program meets the intent of Regulatory Guide 1.54, Revision O.
Relief is requested in accordance with 10 CFR 50.55a(3)(i). The inspections performed by the CR-3 Painting Program provide an adequate level of quality and safety.
The requirement to inspect coatings prior to removal has been removed in the re-write of the ASME Code,Section XI, Subsection IWE which has been approved by ASME and published in the 1998 Edition.
2.4.3 Altemative Examination (as stated)
The condition of the containment vessel bad.r aterial will be verified prior to the application of new paint or coating as required by the CR-3 Painting Program. Additional measures will be invoked to determine the condition of the containment pressure boundary, in the event degradation of the coating is identified. Repairs to the primary containment boundary, if
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necessary, will be conducted in accordance with ASME Section XI Code rules.
2.4.4 Staff Evaluation The staff finds that performing an additional examination prior to the removal of the old paint and documenting its condition (in addition to the licensees' program that is subject to the quality assurance requirements of 10 CFR Part 50 Appendix B) would be a burden without a compensating increase in quality or safety. The Crystal River Painting Program is adequate to monitor the proper remumi vi old paint and the application of new coatings. Therefore, the licensee's proposed attemative to the requirement of Subarticle IWE-2500(b) of the Code is authorized pursuant to 10 CFR 50.55a(s)(3)(ii).
2.5 Relief Reauest No. 98-016-11 2.5.1 Code Reauirement Paragraph IWE-5240, " Visual Examination," of the 1992 Edition,1992 Addenda, of AGME Section XI, requires that the requirements of Paragraph IWA-5240, " Visual Examination," for VT-2 visual examination is applicable following repair, replacement, or modification.
2.5.2 Code Reauirement From Which Relief is Reauested (as stated)
Relief is requested from performing the VT-2 visual examination in connection with system pressure testing following repair, replacement or modification under Article IWE-5000, " System Pressure Tests."
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- L 2.5.3 Basis for Relief (as stated)
Repair / replacements see performed in accordance with the CR-3 repair / replacement program,
- which specifies the repair methods and NDE necessary to ensure the original quality, and construchon requirements of the containment vessel are met. A VT-1 examination is conducted to detect discontinuities and imperfections on the surface of components.
Paragraph IWA-4422.2, " Defect Removal Without Welding or Brazing," states that after removal of defects detected by visual or surface examination, surface examination of the defect removal area shall be performed Paragraph lWE-5210 states that, except as noted within Paragraph IWE-5240, Visual Examination," the requirements of Article IWA-5000 are not applicable to Class MC or Class CC components. Paragraph IWE-5240 states that, the requirements of Paragraph IWA-5240
. corrected from IWA-5246 to IWA-5240 in the 1993 Addenda) for visual examinations are
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l-apphcable. Paragraph IWA-5240 describes a VT-2 visual examination. VT-2 examinations are -
conductcd to detect evidence of leakage from pressure retaining components, with or without leakage collection systems, as required during the conduct of a system pressure test.
Table IWE-2500-1, Examination Category E-P, specifies the examination method of 10 CFR Part 50, Appendix J following each repair, modification, or replaccment and does not specifically identify a VT-2 examination. Appendix J of 10 CFR 50 provides requirements for i
- testing as well as acceptable leakage criteria. These tests are performed by qualified personnel and utilize calibrated' equipment to determine acceptability.. Additionally,10 CFR 50.55a(b)(2)(x)(E) requires a general visual examination of the containment each period that would identify any structural degradt. tion that may contribute to leakage. A VT-2 visual i
examination will not provide additioreal assurance of safety beyond that of current repair / replacement and 10 CFR Part 50, Appendix J practices.
' Relief is requested in accordanct; with 10 CFR 50.55a(a)(3)(i). Pressure testing in accordance with 10 CFR Part 50, Appendix J, provides an adequate level of quality.
2.5.4 Altemative Examination (as stated)
Testing and examination shall be conducted in accordance with 10 CFR, Appendix J. A l
preservice visual examination (VT-1) will be performed on the repair / replacement.
2.5.5 Staff Evaluation ASME Sechon XI,1992 Edition with the 1947 Aodenda, %regraph IWE-5240, requires a i
visual examination (IWA-5240) on areas affected by repair / replacement activities. Paragraph IWA-5240, " Visual Examination," requires a VT-2 examination of pressure retaining components for evidence of leakage. The licensee proposes to perform repair / replacements l
in accordance with its own (CR-3) repair / replacement program, "which specifies the repair methods and nondestructive examinations necessary to ensure the original quality, and construction requirements of the containment vessel are met." As part of the CR-3 l
repair / replacement program, a VT-1 examination is conducted to detect discontinuities and imperfections on the surfaces of components.
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. Table IWE-2500-1, Examination Category E-P, specifies pressure testing via 10 CFR Part 50,
- Appendix J, followmg each repair, modification, or replacement and does not specify a VT-2
. examination. Therefore,' the staff agrees with the licensee that a VT-2 examination will not provide additional assurance of safety beyond the licensee's repair / replacement program, which includes a VT-1 examination to detect surface discontinuities and imperfections, and the pressure test required by 10 CFR Past 50,' Appendix J following each repair, modification, or
~ replacement. On this basis, the staff concludes that the altomative proposed by the licensee is authorized pursuant to 10 CFR 50.55a(s)(3)(ii).
- 2.6 Relief Reauest No. 98-017-11 '
2.6.1 Code Reauirement
' ASME,Section XI,1992 Edition,1992 Addenda, Paragraphs IWE-2420(b) and IWE-2420(c) requires that when component examination results require evaluation of flaws, evaluation of areas of degradation, or repairs in accordance with Article IWE-3000, " Acceptance Standards,"
and the component is found to be acceptable for continued service, the areas containing such flaws, degradation, or repairs shall be re-examined during the next inspection period listed in I
the schedule of the inspection program of Paragraph IWE-2411, " Inspection Program A," or Paragraph IWE-2412, " Inspection Program B," in accordance with Table IWE-2400-1, Examination Category E-C.
2.6.2 Code Reauirement From Which Relief is Reauested (as stated)
Relief is requested from the requirement of Paragraphs IWE-2420(b) and IWE-2420(c) to perform successive examination of repairs.
l 2.6.3 Basis for Relief (as stated)
The purpose of a repair is to restore the component to an acceptable condition for continued service in accordance with the acceptance standards of Article IWE-3000. Paragraph IWE-
- 4150, " Verification of Acceptability," requires the owner to conduct an evaluation of the suitability of the repair including consideration of the cause of failure.
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If the repair has restored the component to an acceptable condition, successive examinations are not warranted if the repair was not suitable, then the repair does not meet Code requirements and the component is not acceptable for continued servics. Neither Paragraph
- lWB-2420(b), Paragraph IWC-2420(b), nor Paragraph IWD-2420(b) requires a repair to be subject to successive examination requirements. Furthermore, if the repair' area is subject to
- accelerated degradation, it would st!'l require augmented examination in accordance with Table IWE-25001, Examination Category E-C.
7 The successive examination of repairs in accordance with Parsgraphs IWE-2420(b) and IWE-2420(c) constitutes a burden without a compensating increase in quality or safety.
in SECY 96-080, *lssuance of Final Amendment to 10 CFR Section 50.55a to incorporate by
. Reference the ASME Boiler and Pressure Vessel Code (ASME Code),Section XI, Division 1, Subsection IWE and Subsection IWL," dated April 17,1996, response to comment #3.3 states,
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"The purpose of IWE-2420(b) is to manage components found to be acceptable for continued service (meaning no repair or replacement at this time) as an Examination Category E-C component, if the component had been repaired or replaced, then the more frequent i
examination would not be needed "
l Relief is requested in accordance with 10 CFR 50.55a(a)(3)(ii). Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a j
compensating increase in the level of quality and safety.
The requirement to perform successive examinations following repairs has been removed in.
the re-write of the ASME Code,Section XI, Subsection lWE, which has been approved by ASME and published in the 1998 Edition.
2.6.4 Altemative Examination (as stated) 1 Successive examinations in accordance with Paragraphs IWE-2420(b) and IWE-2420(c) are i
4 not required for repairs made in accordance with Article IWA-4000.
i 2.6.5 Staff Evaluatign As the Code requires the licensees to verify the -%uacy of repairs, the staff has determined j
that successive examinutions after repair do I,.
!s an additional safety benefit.
Considering the hardship associated with these requirements without a compensating increase in the level of quality and safety, the staff finds that the licensee's proposed attemative to the Code requirements of IWE-2420(b) and IWE-2420(c) is authorized pursuant to 10 CFR 50.55a(a)(3)(ii).
2.7 Relief Reauest No. 98-018-11 2.7.1 Code Reauirement Table IWE-25001, Examination Category E-G (item no. E8.20) requires a torque or tension i
4 test of bolted connections that have not been disassembled and reassembled during the inspection interval.
2.7.2 Code Reauirement From Which Relief is Reauested (ac stated) 1 Relief is requested from ASME,Section XI,1992 Edition,1992 Addenda, Table IWE-2500-1 Examinatum Category E-G, Pressure Retaining Bolting, item E8.20. Table IWE-2500-1 requires a bolt torque or tension test on bolted connections that have not been disassembled 1
and reassemtned during the inspection interval.
2.7.3 Basis for Relief (as stated).
Determination of the torque or tension value would require that the bolting be un-torqued and then re-torquod or re-tensioned. Bolt torque or tension testing is currently required on bolted
. connections that have not been disassembled and re-assembled during the inspection interval.
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a 1 Each containment penetration receives a leak test in accordance with 10 CFR Part 50 Appendix J, Type B test, in accordance with the specified testing frequencies. As noted in
- 10 CFR Part 50 Appendix J, the purpose of Type B tests is to measure the leakage of containment penetrations whose design incorporates resilient seals, gaskets, sealant compounds, and electrical penetrations fitted with flexible metal seal assemblies. The performance of the Type B test itself proves that the bolt torque or tension remains adequate to provide a leak rate that is within acceptable limits. The torque or tension value of bolting
. only becomes an issue if the leak rate is excessive. Once a bolt is torqued or tensioned, it is not subject to dynamic loading that could cause it to experience significant change.
1 Appendix J testing and visual inspection is adequate to demonstrate that the design function is met. Torque or tension testing is not required for any other ASME Section XI, Class 1,2, or 3 bolted connections or their supports as part of the inservice inspection program CR-3 has two
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, pressure unseating penetrations, the equipment hatch and a blind f ange for post-accident sampling. The equipment hatch is normally removed during each outage, however the blind flange is not routinely disassembled during the outage.
' Relief is requested in accordance with 10 CFR 50.55a(s)(3)(ii). Un-torquing and subsequent re-torquing of bo!ted connections, which are verified not to experience unacceptable leakage through 10 CFR, Appendix J, Type B testing, results in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
The requirement to perform bolt torque or tension tests has been removed in the re-write of the j
ASME Code,Section XI, Subsection IWE, which has been approved by ASME and published in'the 1998 Edition.
2.7.4 Altemative Examination (as stated)
The following examinations and tests required by IWE ensure the structural integrity and the leak-tightness of Class MC pressure retaining bolting, and, therefore, no additional attemative examinations are proposed:
1.
Exposed surfaces of bolted connections shall be visually examined in accordance with requirements of Table IWE-2500-1, Examination Category E-G, Pressure Retaining Bolting, item No. E8.10, and
. 2.
Bolted connections shall meet the pressure test requirements of Table IWE-2500-1, l
Examination Category E-P, All Pressure Retaining Components, item E9.40.
2.7,5 Staff Evaluation
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ASidE Sechon'XI,1992 Edition with the 1992 Addenda, Table IWE-2500-1, Examination 2
Category E-G, Pressure Retaining Bolting, item E8.20 requires bolt torque or tension testing on bolted connections that have not been disassembled and reassembled during the inspection interval. This examination is used to aid in the determination that leak-tight seals exist and that the structuralintegrity of the subject bolted connections is maintained. The licensee proposes to use the 10 CFR Part 50, Appendix J, Type B test as an alternative to the Code requirement to verify the integrity of penetrations with bolted connections.
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d The staff agrees with the licensee that bolt torque or tension testing on bolted connections that have not been disassembled or reassembled during the inspection interval would result in a hardship, whereas the leak testing via 10 CFR Part 50, Appendix J, testing (pressure testing) would adequately verify the leak-tight integrity of the containment. The staff finds that compliance with ASME Code requirements will cause a hardship or an unusual difficulty because the un-torquing and subsequent re-torquing of bolted connections involves unnecessary radiation exposure and costs to perform the work. The staff also finds that the altamative approach proposed by the licensee (the pressure test required by 10 CFR Part 50, Appendix J, to verify the leak-tight integrity of bolted connections for containment vessel leak-tight integrity) will provide reasonable assurance of the containment leak-tight integrity, which is the basic purpose of the ASME Code requirements. On this basis, the staff concludes that the altamative proposed by the licensee is authorized pursuant to 10 CFR 50.55a(a)(3)(ii).
3.0 CONCLUSION
Based on the information provided in the relief requests, the staff concludes that for Request for Relief No.98-014, the licensee's proposed altemative will provide an acceptable level of.
j quality and safety. Therefore, the proposed altamative may be authorized for the first 10-year containment inservice inspection interval pursuant to 10 CFR 50.55a(a)(3)(i). For Requests for Relief Nos.98-012,98-013,98-015,98-016,98-017, and 98-018, the staff concludes that -
compliance ~with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality or safety. These proposed attematives will provide reasonable assurance of containment pressure integrity and, therefore, may be authorized pursuant to 10 CFR 50.55a(a)(3)(ii).
Principal Contributor: Clifford G. Munson, NRR Date: October 4,1999 i
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