ML042940196

Condition Report No. 02-00932

ML042940196
Person / Time
Site:	Davis Besse
Issue date:	03/05/2002
From:	- No Known Affiliation
To:	Office of Nuclear Reactor Regulation
References
FOIA/PA-2003-0187 02-00932
Download: ML042940196 (2)

Text

C N()P-LP2001-01 CONDITION REPORT CR Number TITLE: CRDM NOZZLE CRACK INDICATIONS 02-00932 DISCOVERY DATE I TME EVENT DATE TIME SYSTEM / ASSET#

2128/2002 1500 02/28/02 1500 064-02 NA EQUIPMENT DESCRIPTION Reactor Vessel Head DESCRIPTION OF CONDITION and PROBABLE CAUSE (If known) Summarize any attachments. Identify what, when, where, why, how.

0 Completion of Ultrasonic Testing (UT) on all 69 Control Rod Drive Mechanism (CRDM) Nozzles, R using the 'under-head' circumferential probe, and subsequent confirmatory testing using the "top-I down" tool under Framatome procedure 54-ISI-100-08 has revealed additional CRDM cracks l beyond those on CRDM nozzle # 3 as described and reported under CR 02-00891. Intotal, there G are indications of cracks on 5 nozzles:

N NOZLE #1 (location H8): Axial cracks, some with pressure boundary leakage.

A NOZZLE #2 (location G7): Axial cracks, some with pressure boundary leakage, and a partial depth T circumferential crack of approx. 30 degrees. (Note: this crack is sufficiently small that there was no I risk of nozzle failure - stresses had substantial margin before reaching.ASME code allowable values.)

o NOZZLE #3 (location G9): Axial cracks, some with pressure boundary leakage (CR 02-00891)

N NOZZLE #5 (location K7): Small axial cracks, predominantly below the weld, no leakage but requiring repair NOZZLE #47 (location D12): Small axial cracks, predominantly below the weld, no leakage but requiring repair Nozzles #1, 2, and 3 have leakage paths apparent on UT, which is corroborated by boric acid deposits on the reactor head. UT results with the 'top-down' tool also provide some evidence of carbon steel base metal corrosion at nozzles 2 and 3. Nozzle 2 also exhibits channeling of the alloy 600 material to a maximum depth of approximately 0.050 inches to form part of the leakage flow path. These effects must be considered during repair of the nozzles.

(There was initial suspicion of a small axial crack below the weld on nozzle #58 from output using the circumferential probe. However, the top-down tool, which is more comprehensive due to a greater number of probes, confirmed that there was no actual defect.)

SUPV COMMENTS I IMMEDIATE ACTIONS TAKEN (Discuss CORRECTIVE ACTIONS completed, basis for closure.)

Unlike the axial crack indications, the observed circumferential crack on CRDM nozzle #2 Is the type indentified In NRC bulletin 2001-01. However, due to its small size, the circumferential crack is not a safety concern. The 3 nozzles with pressure boundary leakage noted in this CR, i.e. nozzles #1, 2, and 3 are reportable per T.S. 3.4.6.2.a. This Issue was already reported under CR02-0891 on 2127/02 for nozzle #3, however, an update of that report will be needed. This CR will ensure the reporting requirements are satisfied.

Resolution of the issues will be addressed by CR 02-00891, which was classified as OSignificant-Root Cause".

QUALITY ORGANIZATION USE ONLY IDENTIFIED BY (Check one) El Seol-Revealed ATTACHMENTS Quality Org. Initiated E Yes 2 IndividuaVlWork Group E Internal Oversight Quality Org. Follow-up El Yes El No El Supervision/Management El External Oversight g Yes E No ORIGINATOR ORGANIZATION I DATE SUPERVISOR DATE PHONE EXT.

LANG, T LCM 2128/2002 LANG, T 3/5/2002 8116 Page 1 of 2 H53

NOP-LP-2001-01 CONDITION REPORT JoCR Number TITLE: CRDM NOZZLE CRACK INDICATIONS 02-00932 SRO EQUIPMENT E VALUATION IMMEDIATE ORGANIZATIO0N MODE CHANGE REVIEW OPERABLEREQUIRED INVESTIGATION REQUIRED NOIID RESTRAINT L g3 Yes 0 No El Yes 10 No a3 WA 0 Yes i] No [] Yes il No NIA EdYes 0 No MODE ASSOCIATED TECH SPEC NUMBER(S) ASSOCIATED LCO ACTION STATEMENT(S)

A L ij#~ -g~

N -1WI DECLARED REPORTABLE? One Hour W1AAPPLICABLE UNIT(S) 0 NOPERABLE (Date/Time) RYes EINo , }1 P 2/27/02 / 1330 ]Evat Required Other 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Ul E0 U2 E0 Both E COMMENTS R Refer to CR 02-0891. Made 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Non-Emergency update to the initial report (Event Number A 38732) to the NRC. Update was made via ENS at 1921, 3/5/02. The disposition of this CR will be T tied to that of CR 02-0891. NRC Resident Inspector was also notified, as well as the applicable I personnel listed in DB-OP-00002.

o Current Mode - Unit I Power Level - Unit 1 Current Mode - Unit 2 l Power Level - Unit 2 N 6 0 S SRO-UNIT 1 SRO - UNIT 2 DATE Ploeger, T Steenbergen, C 3/5/2002 CATEGORY/ EVAL ASSIGNED ORGANIZATION DUE DATE R REPORTABLE?

CF DBE 4/14/2002 E Yes O]No EOLERNNo.

ORPATREND CODES Comp Type I ID Resp u REPORTASILITY REVIEWER I Process I Activity/ Cause Code(s) (If Cause T or W) Org A Wolf, G SUPV HDW 0600 T

- __ 0 DATE MRS y 03/08/02 INVESTIGATION OPTIONS CLOSED BY DATE E Generic Impliations El Part 21 [ MaintRule OE Evaluation Page 2 of 2