ML20206N192

Provides Revised Attachment 2 for Alternative Request IWE-02,originally Submitted 990429 Re Bolt Torque or Tension Testing of Class Mc pressure-retaining Bolting as Specified in Item 8.20 of Article IWE-2500,Table IWE-2500-1

ML20206N192
Person / Time
Site:	Grand Gulf, Arkansas Nuclear, River Bend, Waterford
Issue date:	05/10/1999
From:	Kansler M ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CNRO-99-00016, CNRO-99-16, NUDOCS 9905170164
Download: ML20206N192 (6)

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Jackson, MS 39286-1995 Tel 601368 5760 Michael R. Kansler Vice PresgWnt Ope <@ons Support May 10,1999 U. S. Nuclear Regulatory Comniission Attn.: Document Control Desk Mail Stop OP1-17 Washington, DC 20555-0001

Subject:

Entergy Operations, Inc.

Alternatives to ASME Code Requirements Arkansas Nuclear One - Units 1 & 2 Grand Gulf Nuclear Station Docket Nos. 50-313 & 50-368 Docket No. 50-416 License Nos. DPR-51 & NPF-6 License No. NPF-29 River Bend Station Waterford Steam Electric Station - Unit 3 Docket No. 50-458 Docket No. 50-382 License No. NPF-47 License No. NPF-38

Reference:

CNRO-99/00004," Alternatives to ASME Code Requirements," April 29,1999 CNRO-99/00016 Ladies and Gentlemen:

In the referenced letter, Entergy Operations, Inc. (Entergy) proposed three alternatives to various requirements of ASME Boiler and Pressure Vessel Code Section XI,1992 Edition, 1992 Addenda. One of the alternatives, IWE-02 (Attachment 2 of the referenced letter),

pertains to bolt torque or tension testing of Class MC pressure-retaining bolting as specified in item 8.20 of Article IWE-2500, Table IWE-2500-1, " Examination Category E-G, Pressure Retaining Bolting." j By this letter, Entergy is providing a revised Attachment 2 for Alternative Request IWE-02. g This revised attachment contains site-specific supplementary information pertaining to /(J7 7 ;

Arkansas Nuclear One - Units 1 and 2 that was inadvertently omitted from the referenced letter. The supplemental information is denoted by revision bars in the page margins. This information does not affect the information pertaining to Grand Gulf Nuclear Station, River Bend Station, or Water Steam Electric Station - Unit 3. Entergy personnel have discussed this submittal with Mr. George Dick of the NRR Project Directorate IV staff.

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Altarnativas to ASME Coda R:quiram:nts CNRO-99/00016 May 10,1999

! Page 2 of 2 I Should you have any questions regarding this submittal, please contact Guy Davant at (601) 368-5756. l Very truly yours,

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MAK MRK/SJB/GHD/baa l Mhattachment I cc: Mr. C. M. Dugger (W-3) l Mr. R. K. Edington (RBS) l Mr. W. A. Eaton (GGNS)

Mr. C. R. Hutchinson (ANO)

Mr. J. R. McGaha (ECH) l Mr. G. F. Dick, NRC Project Manager (Entergy) l Ms. J. L. Dixon-Herrity, NRC Senior Resident inspector (GGNS)

Mr. T. R. Farnholtz, NRC Senior Resident Inspector (W-3)

Mr. R. J. Fretz, NRC Project Manager (RBS)

Mr. N. D. Hilton, NRC Project Manager (ANO-1)

Mr. K. M. Kennedy, NRC Senior Resident inspector (ANO)

Mr. E. W. Merschoff, NRC Region IV Regional Administrator Mr. M. C. Nolan, NRC Project Manager (ANO-2)

Mr. C. P. Patel, NRC Project Manager (W-3)

Mr. G. D. Replogie, NRC Senior Resident inspector (RBS)

Mr. S. P. Sekerak, NRC Project Manager (GGNS) 1 l

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.- CNRO-99/00016 Attachm::nt 2 (rsvis:d)

Page 1 of 4 ARKANSAS NUCLEAR ONE - UNITS 1 & 2 GRAND GULF NUCLEAR STATION RIVER BEND STATION WATERFORD STEAM ELECTRIC STATION - UNIT 3 CONTAINMENT INSPECTION BOLTING TORQUE / TENSION TEST ALTERNATIVE REQUEST # IWE-02, Rev. O SYSTEMS / COMPONENTS FOR WHICH AN ALTERNATIVE IS PROPOSED Class MC pressure retaining bolting, Examination Category E-G, Item 8.20 of IWE-2500,

" Examination and Pressure Test Requirements," Table IWE-2500-1, ASME Section XI,1992 Edition with the 1992 Addenda.

CODE REQUIREMENT ,

ASME Section XI,1992 Edition with 1992 Addenda, Table IWE-2500-1 requires a bolt torque or tension test once each interval.

CODE REQUIREMENT FOR WHICH AN ALTERNATIVE IS PROPOSED l

Pursuant to 10CFR50.55a(a)(3)(ii), Entergy proposes an alternative to performing the Code-required bolt torque or tension test on the bolt connections that are not disassembled and reassembled during the inspection interval. The torque or tension testing will result in hardship without commensurate increase in the level of safety or quality.

BASIS FOR ALTERNATIVE 10CFR50.55a was amended, as cited in the Federal Register (61 FR 41303), to require the use of the 1992 Edition,1992 Addenda, of ASME Section XI when performing containment examinations. Bolt torque or tension testing is required on bolted connections that have not been disassembled and reassembled during the inspection interval. Determining the torque or tension value would require the bolting to be loosened and then re-torqued or re-tensioned. Discussions of bolted connections are presented below for each Entergy site.

These discussions address pressure-seating and pressure-unseating bolted connections.

Pressure-seating bolted connections are considered to be those connections that have additional seating loads due to accident pressures on the inboard (containment) side of the penetration. Thus pressure-seating connections have a low potential for leakage under accident loads. In contrast, pressure-unseating botted connections see unseating loads due to accident pressures on the inboard (containment) side of the penetration. Therefore, the potential for leakage through a pressure-unseating connection is greater than for a pressure-seating connection. As a result, the integrity of the connection is more dependent on proper tensioning of the treaded fasteners, possibly increasing the potential for leakage.

. CNRO-99/00016 Attachmsnt 2 (ravissd)

Page 2 of 4

1. Arkansas Nuclear One Penetration bolted connections are pressure seating during containment pressurization following a design basis accident, except in five cases as discussed below. Specifically, the equipment hatch bolted connections seat against the interior surface of containment l during containment pressurization and are therefore pressure seating. The bolted I

connections associated with the fuel transfer tube blind flange are also pressure seating. The exceptions are:

a. Both bulkheads on both personnel air locks and both emergency air locks are fitted with an electrical penetration assembly. Each of the four electrical penetration assemblies has a pressure seating connection on the inboard side and a pressure unseating connection on the outboard side. Thus, pressure loading on the unseating connection would only occur upon failure of the pressure seating connection.

j b. Both personnel air locks and emergency air locks have a bolted handwheel shaft

seal retainer on both the inner and outer bulkheads. The emergency air locks also I

have an additional door operating mechanism on both inner & outer bulkheads.

Thus, pressure loading on these unseating connections would occur only if the inboard door is open, or if the inboard bulkhead is breached.

c. Both personnel air locks and the emergency air lock on ANO-2 have a telephone penetration assembly that is pressure seating on the inboard side and unseating on i the outboard side. This penetration is only located in the outboard bulkhead. '

Thus, pressure loading on the unseating connection would only occur upon failure of the pressure seating connection.

d. The ANO-1 emergency air lock has eight inservice inspection (ISI) penetrations in the top of the air lock barrel assembly. Four of these are inside the reactor building and are pressure seating. The other four are outside the reactor building and are pressure unseating. Pressure loading on the four outside containment penetrations would only occur upon failure of the pressure seating connections inside the containment.

e. The ANO-2 electrical penetration assemblies have a penetration header plate with redundant o-rings that is attached to the weld flange with bolting on the Auxiliary Building side. These connections are pressure unseating.

2. Grand Gulf Nuclear Station Penetration bolted connections are pressure-seating, except for the following two cases:

a. Both bulkheads on both containment personnel airlocks are fitted with an electrical penetration assembly. Each of the four electrical penetration assemblies has a pressure-seating connection on the inboard side and a pressure-unseating l

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, CNRO-99/00016 -

Attachmsnt 2 (rsvisad)

Page 3 of 4

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connection on the outboard side. Thus, pressure loading on the unseating connection would only occur upon failure of the pressure-seating connection.

b. Both containment airlocks have a bolted handwheel shaft seal retainer and a bolted blind flange used for testing on the outboard bulkhead. (The flange is local leak-rate tested.) Thus, pressure loading on these unseating connections would occur only if the inboard door is open, or if the inboard bulkhead is breached.

3. River Bend Station Penetration bolted connections are pressure-seating, except for the following two cases:

a. The equipment hatch seats against the exterior surface of the containment and is therefore pressure-unseating. The equipment hatch is removed during maintenance outages, when necessary, and during each refueling outage. Prior to plant startup, the hatch and flange are Type B leak-tested in accordance with 10CFR50 Appendix J.

b. The fuel transfer tube blind flange bolting connection is pressure-unseating. The blind flange is removed during each refueling outage. Prior to plant startup, the flange is Type B leak-tested in accordance with 10CFR50 Appendix J. I

4. Waterford-3 Penetration bolted connections are pressure-seating except for bolted connections located within the exterior personnel airlock doors. These connections are Type B pressure-tested in a pressure-unseating fashion during leak tests of the airlocks in accordance with 10CFR50 Appendix J.

Each containment penetration is leak-tested in accordance with 10CFR50 Appendix J.

Successfully performing the test provides evidence the bolt torque or tension remains adequate to provide a leak rate within acceptable limits. The torque or tension value of bolting becomes an issue only 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. Appendix J testing and visualinspection are adequate to demonstrate the design function is met. Torque or tension testing is not required for any other ASME Section XI, Class 1,2, or 3 bolted connection or its supports as part of the Inservice inspection program.

The requirement to perform bolt torque or tension tests has been removed from the 1998 Edition of Subsection IWE of ASME Section XI. Entergy believes 10CFR50, Appendix J  :

Type B testing provides an equivalent level of quality and safety to the bolt torque testing required by Table IWE-2500-1. Therefore, loosening and subsequent re-torquing bolted connections that are verified leak-tight per Appendix J testing results in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

, CNRO-99/00016 Attachm:nt 2 (rsvissd)

Page 4 of 4 The NRC has approved a similar request for Davis-Besse Nuclear Power Station (#RR-E7) .

ALTERNATE EXAMINATIONS The following examinations and tests required by Subsection IWE ensure the structural integrity and the leak-tightness of Class MC pressure retaining bolting, therefore, no additional alternative 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.

2. Bolted connections shall meet the pressure test requirements of Table IWE-2500-1, Examination Category E-P, All Pressure Retaining Components, item E9.40.

In addition,10CFR50 Appendix J Type B testing is currently performed on each containment i penetration at least once each inspection interval. )

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' Letter dated June 30,1998, " Relief from Certain ASME Code Requirements for Inservice inspection for Facility Operating License No. NPF Davis-Besse Nuclear Power Station, Unit 1 (TAC No.

MA0414)*