ML20217J014

Requests Relief to Use Performance Demonstration Initiative Program as Alternate to ASME Boiler & Pressure Vessel Code Requirements Re Plant Second ten-yr ISI

ML20217J014
Person / Time
Site:	Calvert Cliffs
Issue date:	10/14/1997
From:	Cruse C BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
PDI, NUDOCS 9710200014
Download: ML20217J014 (7)

Text

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C u rusIs 11. C ut u Hahinmre Ons and Lieurie Cornpany Vice Preudent Cahert Clif fs Nuslear Power Plant Nucicar Energy 1650 Cah ett Chif 6 P,ukw ay i Lustiy. htaryland 20657 l 410 495-445$ I October 14,1997 U. S. Nuclear Regulatory C insion l

Washington, DC 20$55 ATTENTION: Document Control Desk SUILIECT: Calvert Clif1s Nuclear Power Plant Unit No- 1 & 2; Docket Nos. 50 317 & $0 318 Reactor Pressure Vessel Second Ten-Year Inservice 'nspection Relief Request to Use Performance Demonstration Imtlative Program as an Alternative to Code

}{tqukement

REFERENCES:

(a) latter from Mr. R. A. Capra (NRC) to Mr. G. C. Creel (PGE), dated January 11,19c0, Approval of Second Ten Year Inservice inspection Program Plan for Calvert Cliffs Units 1 and 2 (Unit i TAC 67094; Unit 2 TAC No. 67095)

(b) NRC Proposed Generic Communication; " Effectiveness of Ultrasonic Testing Systems in Inservice Inspection Programs," Federal Register I Notice, Volume 61 Number 2!2, December 31,1996 page 69117 (c) Letter from Mr. R. A. Capra (NRC) to Mr.1. Johnson (Comed), dated hiay 13,19P7, Evaluation of the First 10 Year Interval luspection Program Plan Request for Relief NR 29 Braidwood Station, Units 1 and 2 (TAC Nos. M97134 and M97135)

(e Meeting Summary by Mr. A. W. Dromerick (NRC), dated \

October 2,1997, Sunmary of August 27, 1997 Meeting Regarding Calvert Cliffs Nuclear Power Plant, Units Nos. I and 2 Reactor Pressure Vessel 10 Year Inservice inspection Project /

Pursuant to 10 CFR Part 50, Paragraph 50.55a(a)(3)(i), Baltimore Gas and Electric Company hereby proposes an alternative to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) requirement concerning the Calvert Cliffs Nuclear Power Plant (CCNPP) reactor pressure vessel (RPV) Second Ten Year Inservice inspecti on (ISI). Calvert Cliffs Technical Specification 4.0.5 states in par *., " Inservice inspection of ASME Code Class 1,2, and 3 components

. . . shall be performed in accordance with Section XI of the ASME Boller and Pressure Vessel Code and applicable Addenda as required by 10 CFR 50, Section 50.55a(g) . . . ." Paragraph 50.55a(a)(3)(i) allows h ipo$ b b PDR-17 hl![Il$lhll! }l!'$lhll} l g '

Docum3nt Control Desk October 14,1997 Page 2 the use of alternatives to the requirements of Paragraph 50.55a(g), that provide an acceptable level of quality and safety, when authorized by the Director of the Ofuce of Nuclear Reactor Regulation.

The Second Ten Year ISI Program Plan for CCNPP, Units I and 2 meets the requirements of the 1983 Edition, Summer 1983 Addenda of Section XI of the ASME Code, as approved by Nuclear Regulatory Commission (NRC) letter dated January 11,1990 (Reference a). Table IWB 25001 in Section XI describes the method of examination for the components and parts of pressure retaining boundaries.

Article IWA 2232 of Section XI requires ultrasonic examination (UT) of vessel welds to be conducted in accordance with Article 4 of Section V. As an alternative, BGE proposes to use examination procedures, equipment, and personnel qualified by performance demonstration in accordance with the Performance Demonstration initiative (PDl) program.

The PD1 program was developed by the U.S. Nuclear Industry to manage implementation of the perfonnance demonstration criteria of Appendix Vill,Section XI of the ASME Code,1992 Edition, 1993 Addenda. Appendix Vill was developed to ensure the efTectiveness of the UT examinations within the nuclear industry by means of e rigorous, item specific, performance demonstration. The performance demonstration requires that equipment, procedures, and examlurs be tested on Dawed and notched materials and configurations similar to those found in actual plant conditions, llence, performance based UT techniques provide a higher degree of reliability for detection and characterization of flaw when compared to the conventional amplitude based UT techniques that is required by the current Code of record for CCNPP. The NRC staff has assessed the PDI program activities and found that the "PD1 has established and is in the process of executing a well planned and effective program . . . "(Reference b).

In addition, the NRC staff has recently approved the use ef PDI techniques at Commonwealth Edison Company's Braidwood Station for the first ISI interval to be implemented during the Units 1 and 21997 outages (Reference c).

On August 27,1997, we met with the NRC stafTto discuss our strategy for CCNPP Units I and 2 Second 10 Year RPV Inservice inspection (Reference d). During this meeting, we informed the staff of our plan to implement the PDI techniques by invoking Section XI, Paragraph IWA 2240, provision for alternative examinations. Instead, the stalt recommended that we submit a proposal in accordance with 10 CFR 50.55a(3) for their review and evaluation. At this meeting, we also infonned the staff of our intention to satisfy the 10 CFR 50.55a(g)(6)(ii)(A) " augmented," RPV inspection requirements, in addition to the Code Requirements during the Second 10 Year ISI.

COMPONENT FOR WHICH_RELLEF IS REOUESTED

+ Components that will be examined using PDI techniques only:

=> CCNPP Units I and 2 RPV Circumferential Welds (Weld Nos. 8-203,9 203,and 10 203)

=> CCNPP Units 1 and 2 RPV Longitudinal Welds (Weld Nos.1203A/B/C,2 203A/B/C, and 3 203Ml/C)

=> CCNPP Units I and 2 RPV Lower llead Welds (Weld Nos,4 204 and 1204 A)

D6cument Control Desk October 14,1997 Page 3 i

+ Components that will be examined using PD1 Techniques in Combination with AshtB Code Techniques:

o CCNPP Units 1 & 2 RPV Vessel to Flange Weld (Weld No. 7 203 This weld will be examined from the flange seal surface using AShiE Code techniques for detection of Daws parallel to the weld pinne Examination for transverse Daws will be conducted from the vessel inside surface using in u dmiques.)

o CCNPP Units 1 & 2 RPV Nozzle to-Shell Welds (Weld Nos.10 205A/I) and 4 205A/B/C/D PD) techniques will be applied from the vessel wall for detection of transverse reacctors. ar the detection of Daws that are parallel to the weld, examinations will be conducted from the nozzle bore using standard ASME Code techniques.)

CODE REOUlltEMENTS FOR WillCILRTLIEF IS llEQ1]ESIEI)

American Society of Mechanical Engineers Code,Section XI,1983 Edition, with the Summer 1983 Addenda, Subsection IWB, Table IWil 25004, Examination Cstegory B A Items 111.11. Bl.12,111.22, 111.30, and B D ltem 113.90 require volumetric examination. The requirements for volumetric examinations are stated in Article IWA 2232, which requires that examinations be conducted in accordance with Article 4 of Section V as amended by Section XI.

PROPOSED ALTERNATIVE Examination procedmes, equipment, and personnel qualified by performance demonstration will be utilized, in accordance with the PDI Program, in combination with Section V, Article 4 techniques.

Attachment (1) provides a comparison of the proposed PD1 technique for CCNPP and the standard Article 4,Section V and Regulatory Guide 1.150 procedures.

As a minimum, all Code requirements of the 1983 Edition through Summer 1983 Addenda of Section XI will be implemented, except where specific differences have been identi0ed in this submittal and Reference (a). ?n addition, as mentioned above, it is our intention to satisfy the 10 CFR 50.55a(g)(dii)(A)" augmented," RPV insp:ction requirements.

SUPPORTING INFORMATION llaltimore Gas and Electric Company has contracted with Southwest Research Institute (SwRI) to perfomi the Second Ten Year RPV examination using a combination of the PDI quali0ed techniques and ASME Section V Article 4 techniques. South', vest Research Institute's procedures were quali0ed in accordance with the PD1 program covering Supplements 4, " Qualification Requirements for the Clad / Base Metal Interface of Reactor Vessel,' and 6, "Quall0 cation Requirements for Reactor Vessel Welds Other than Clad /Dase Metal Interface," of Appendix Vill,Section XI ASME Code. Both double-and single sided approaches were qualined for Supplement 4 applicat!ons and for Supplement 6 applications up through 12 inch wall thicknesses. (Southwest R^ search Institute's PDI certification is on file at the Electric Power Research Institute Non-Destructive Examination Center in Charlotte, NC.)

Southwest Research Institute's PDI detection procedure utilizes two types of search units (55 degree, multibeam) when scanning can be accomplished from two sides of the weld, and three types of search units (45,55, and multibeam) when scanning can only be accomplished from one side of the weld. The

17ocument Control Desk

• October 14,1997 Page 4 multibeam search unit is used to examine the inner 25 percent thickness. The 45 and 55 degree shear.

wave search units are used to examine the outer 75 percent. A 0-degree search unit may also be used to detect laminar reDectors and determine component thickness. (NOTE: Baltimore Gas and Electric Company has instructed SwRI to scan from two sides of each weld whenever it is possible.) Scanning is performed: (1) perpendicular to the weld fer Daws orientated parallel to the weld; and (2) parallel to the weld for Daws orientated perpendicular (transverse) to the weld. Flaw discrimination inethods are independent of signal amplitude. Scanning sensitivities are determined based on the actual material noise.

Analysis and sizing of indications are performed by qualined Level 111 Data Analysts using SwRI procedures. Regardless whether the detection examinations are being performed per ASME Code or PDI procedures, SwRl's sizing procedures utilize tip-diffraction methods qua. lined in accordance with the PD1 guidelines.

SAFETY COMMrITEE REVIFM The proposed teller request has been reviewed by our Plant Operations and Safety Review Committee, and they have concluded that the proposed alternative provides an acceptable level of quality and safety.

SC11EllULE The Second Ten Year Calvert Cliffs Unit 1 RPV ISI is scheduled to take place during the spring 1998 refueling outage. We request that the NRC review and approve our proposed alternative by February 15,1998, to allow a timely preparation and implementation of the PDI procedures.

Should you have questions regarding this matter, we will be pleased to discuss them with you.

Very truly yours, f

/ l'

/ ;m ,W  ?&t/ -

./

CilC/GT/bjd Attechment: (1) Comparison of Reactor Pressure Vessel Welds Examination Techniques cc: R. S, Fleishman, Esquire 11. J. Miller, NRC J. E. Silberg, Esquire Resident inspector, NRC Director, Project Directorate 1 1, NRC R.1. McLehn, DNR A. W. Dromerick, NRC J 11. Walter, PSC S. J. Todd, Sw R1

ATTACilMENT (1)

COMPARISON OF REACTOR PRESSURE VESSEL WELDS EXAMINATION TECIINIQUES Calvert Cliffs Nuclear Power Plant Units 1 and 2 October 14,1997

ATTACIIMENT m -

COMPARISON OF REACTOR PRESSURE VESSEL SIIELL WELD EXAMINATION TECtINIQUES 4 SnRI PDUAppendix VIII Qualified Procedser Description (Code Reference) .

Regulatory Guide I.150 Procedure  :

Examination Angles Four transducers required to perfonn the detection Two types of search umts; a multibeam search unit scans 0*,45', and 60' plus a multibeam transducer and 55' search unit, are used to perform the double (Section V, T-441) for clad-to-base metal interface (Regulatory Guide sided detection examinations. i 1.150 requirement)is used. Three types of scarch units, multibeam; 45* and 55 s

. j

, are used for single sided detection examinations. The 7{

multibeam search units are used to examine the near surface, and the 45' and 55' search units are used to examine the remainder of the wall These examination angles were successfully qualified under the PDI protocol using the PDI g- cry uu test blocks.

Instrument Calibrations Section V requires that instrument screen height and SwRrs PDI-qualified procedure does not require that (Section V. T 431,Section XI, amplitude control linearity be evaluated at least every linearity checks be performed on site before and after IWA-2232) three months.Section XI requires that these linearity examinations because amplitude lineanty is not relied checks be performed before and after the upon for evaluation of flaws. SuRI does perform examinations performed during one outage. instrument linearity checks at least every 6 months as part of the maintenance and Loumucra certification Process.

System Calibrations Requires that the original system calibration be per- One calibration standard is used for the multibeam (Section V, T-435) formed on the Code basic calibration block. It allows search unit and another standard is used for the 45' the use of different types of reference blocks and and 55'scarr.h units. These standards contain a series electronic simulators to perform system calibration of side drilled holes and are used to establish a verifications. calibrated time base and initial sensithity. Periodic sweep calibration checks are made and sensitivity checks are made on the vessel wa!L I

A'ITACHMENT (1)

COMPARISON OF REACTOR PRESSURE VESSEL SHELL WEIE EXAMINATION TECHNIQUES Uf--- (Code Reference) R, Standard Secties

_ _y weide V,XI, 1.150 Precedere hRI N ( " VH1 W h Scanning Sensitivity Scanning is performed at the reference level Initial sensitivity is incicaxd. if m, until (Section V,T-425) sensitivity when electronic distance amplitude background noise from the riaterial in the correction (DAC) is used for automated examinations. examinaten area equals a level specified in the qualified procedure. This method of determining scanning sensitivity was successfully qualified under the PDI protocol using the PDI p vy.-- test blocks.

Recording level Section V requires recording and evaluation at 50% No amplitude thresholds are used. Data are recorded (Section V,T-44I) DAC. Regulatory Guide 1.150 requires recording and and evaluated independently of signal amplitude.

evaluation at 20% DAC for the inner 25% of material This evaluation method was successfully qualified thickness. under the PDI protocol using the PDI test blocks.

Scan Index, Pulse Repetition Sec'?ou V requires a minimum merement overlap of Scanning overlap is 10 % for the near surface Rate 10% of the dimension of the piezoelectric element multibeam search units and 40% for the other (Section V, T-425 and Section between scans.Section XI requires 50% overlap detection search units, as qualified under the PDI XI,IWA-2232) when not scanning in beam direction. Regulatory protocol using the PDI test blocks. Pulse repetition Guide 1.150 requires 25% minimum overlap for rate is set such that data are collected at 0.040-inch detection and 0.25' maximum increment for increments in the directen ofscan.

characterization.Section XI also requires a pulse repetition rate sufficient to provide at least 10 %

overlap of the minimum beam dimension.

F:aw Sizing and Evaluation Amplitude based sizing at 50 % DAC. Other Multibeam tip diffraction techniques are used for (Section V,T 441 and T-451) techniques and methods may be used. through-wall sizing. The length sizing is accom-plished using amplitude drop methods. Beam spicad calculations are not pu foi o.cd for these keniqws.

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