ML061080394

Relief, Request to Use a Later Edition and Addenda of the ASME Boiler and Pressure Vessel Code,Section XI for Repair/Replacement Activities at PVNGS in Accordance with 10 CFR 50.55a(g)(4)(iv)

ML061080394
Person / Time
Site:	Palo Verde
Issue date:	04/07/2006
From:	Mauldin D Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05461-CDM/TNW/RJR
Download: ML061080394 (5)

Text

10 CFR 50.55a(g)(4)(iv)

David Mauldin Vice President Mail Station 7605 Palo Verde Nuclear Nuclear Engineering Tel: 623-393-5553 PO Box 52034 Generating Station and Support Fax: 623-393-6077 Phoenix, Arizona 85072-2034 102-05461 -CDM/TNW/RJR April 7, 2006 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Units 1, 2 and 3 Docket Nos. STN 50-528/5291530 Request to Use a Later Edition and Addenda of the ASME Boiler and Pressure Vessel Code, Section Xi for Repair/Replacement Activities at PVNGS in Accordance with 10 CFR 50.55a(g)(4)(iv)

In accordance with the guidance provided in NRC Regulatory Issue Summary (RIS) 2004-16, "Use of Later Editions and Addenda to ASME Code Section Xl for Repair/Replacement Activities" dated October 19, 2004 and in accordance with 10 CFR 50.55a(g)(4)(iv), APS is requesting NRC approval to use a later Edition of the ASME Boiler and Pressure Vessel Code. Specifically, APS requests approval to use ASME Section Xi, 2001 Edition, no Addenda, paragraph IWA-4461.3, "P-Nos. 8 and 42 Materials," IWA-4461.4, "Alternatives to Mechanical Processing" and paragraph IWA-4461.4.1, "Qualification of Thermal Metal Removal Process," as described in the enclosure to this letter.

During refueling outages U3R12, U2R13 and U1R13, APS will be installing additional vent and drain lines in various sections of the safety injection (SI) system. APS will be using a thermal metal removal process during the modifications to the SI system. The current ASME Code of record for PVNGS is the 1992 Edition with 1992 Addenda which requires the mechanical removal of material from the thermally processed area on F'-

No. 8 and P-No. 43 materials. The use of the 2001 Edition and no Addenda of the ASME code will allow APS to qualify the thermal metal removal process [electro-discharge machining (EDM)] thereby avoiding the need to mechanically remove additional material from the processed areas.

APS requests NRC approval to use the later edition and addenda of the ASME code identified in the enclosure to this letter at PVNGS Units 1, 2 and 3 for the remainder of A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callawey

• Comanche Peak

• Diablo Canyon

• Palo Verde

• South Texas Project

• Wolf Creek 4-04:7

U. S. Nuclear Regulatory Commission Page 2 ATTN: Document Control Desk Request to Use a Later Edition and Addenda of the ASME Code their respective second 10-year Inservice Inspection Intervals which end in January 2008, March 2007 and July 2008 respectively. It is requested that the NRC provide their approval prior to Unit 3 entering Mode 2 (currently scheduled for the week of May 9, 2006)) in order to support the restart of PVNGS Unit 3 from the refueling outage.

There are no commitments being made in this letter. If you have any questions, please contact Thomas N.Weber at (623) 393-5764.

Sincerely, CDM/TNW/RJR

Enclosure:

Request to Use a Later Edition and Addenda of the ASME Code per 10 CFR 50.55a(g)(4)(iv) and RIS 2004-16 cc: B. S. Mallett NRC Region IV Regional Administrator M. B. Fields NRC NRR Project Manager G.G.Warnick NRC Senior Resident Inspector for PVNGS

- L Enclosure Request to Use a Later Edition and Addenda of the ASME Code per 10 CFR 50.55a(g)(4)(iv) and RIS 2004-16

Request to Use a Later Edition and Addenda of the ASME Code per 10 CFR 50.155a(g)(4)(iv) and RIS 2004-16 I. Applicable Code Edition and Requirements The current ASME Code of record for PVNGS is the 1992 Edition with 1992 Addenda. The applicable code requirements in the 1992 Edition with 1992 Addenda are as follows:

IWA-4322, "Process Requirements for P-No. 8 and P-No. 43 Materials "If thermal removal processes are used on P-No. 8 and P-No. 43 materials, a minimum of 1/16 in. shall be mechanically removed form the thermally processed area."

II. Proposed Alternative Code Edition and Requirements The proposed code is the 2001 Edition, no Addenda. The applicable code Requirements from that code are as follows subject to the limitations and modifications identified in 10 CFR 50.55a(b).

IWA-4461.3, "P-Nos. 8 and 43 Materials"

'If thermal removal processes are used on P-No. 8 and P-No. 43 materials, at least 1/16 in. (1.6 mm) of material shall be mechanically removed from the Thermally processed area."

IWA-4461.4, "Alternatives to Mechanical processing" Mechanical processing of thermally cut surfaces for materials identified in IWA-4461.3 is not required when the alternative of IWA-4461.4.1 is used.

IWA-4461.4.1, "Qualification of Thermal Metal Removal Process"

'Mechanical processing of thermally cut surfaces is not required when the thermal metal removal process is qualified as follows:

(a) The qualification test shall consist of two coupons of the same P-No.

material cut in production.

4b) The qualification coupons shall be cut using the maximum heat input to be used in production.

(c) The thermally cut surface of each coupon shall be visually examined at lOX and shall be free of cracks. The owner shall specify surface roughness acceptable for the application and shall verify that the qualification coupon meets the criterion.

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Request to Use a Later Edition and Addenda of the ASME Code per 10 CFR 50.!55a(g)(4)(iv) and RIS 2004-16 id) Each qualification coupon shall be cross sectioned, and exposed surfaces shall be polished, etched with a suitable etchant, and visually examined at 1OX. All sectioned surfaces shall be free of cracks.

(e) Corrosion testing of the thermally cut surface and heat affected zone shall be performed if the cut surface is to be exposed to corrosive media.

Alternatively, corrosion resistance of the thermally cut surface may be evaluated. The owner shall specify the acceptance criteria."

In accordance with the limitations contained in 10 CFR 50.55a(b)(2),

referenced below, Section IWA-4461.4.2, "Evaluation of Thermally Cut Surfaces," of the 2001 Edition will not be used.

10 CFR 50.55a(b)(2) states that "As used in this section, references to Section Xl of the ASME Boiler and Pressure Vessel Code refer to Section Xl, and include the 1970 Edition through the 1976 Winter Addenda, and the 1977 Edition (Division 1) through the 2003 Addenda (Division 1), subject to the following limitations and modifications:"

(xxiii) Evaluation of Thermally Cut Surfaces. "The use of the provisions for eliminating mechanical processing of thermally cut surfaces in IWA-4461.4.2 of Section Xl, 2001 Edition through the latest edition and addenda incorporated by reference in paragraph (b)(2) of this section are prohibited."

Enclosure Page 2