IR 05000336/1985018

Insp Rept 50-336/85-18 on 850429-0503.No Violation Noted. Major Areas Inspected:Areas of Inservice Insp Program Activities,Including Ultrasonic Exam of Piping & Eddy Current Test of Steam Generator Tubes & Sleeves

ML20127E524
Person / Time
Site:	Millstone
Issue date:	05/29/1985
From:	Gray E, Wiggins J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20127E492	List: IR 05000336/1985018 ML20127E489
References
50-336-85-18, NUDOCS 8506240575
Download: ML20127E524 (5)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Report N /85-18 Docket N License No. DPR-65 Licensee: Northeast Nuclear Energy Company P.O. Box 270 Hartford, Connecticut Facility Name: Millstone Nuclear Power Station, Unit 2 Inspection At: Waterford, Connecticut Inspection Conducted: April 29, - May 3, 1985 Inspectors:

E. H. Gray, LeacVReactor Engineer h3 date

/8 Approved by:

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M dats 7d y.pWiggins, pff rf, Materials Uand ProcesW Section, DRS Inspection Summary: Inspection during April 29 - May 3, 1985 (Report N /85-18).

Areas Inspected: Routine, unannounced inspection by one region based inspec-to The inspection included the areas of Inservice Inspection (ISI) program activities including ultrasonic examination of piping and eddy current examina-tion of steam generator tubes and steam generator sleeves. Work in progress including sleeve installation on steam generator tubes and disassembly of the service water pump "A" were observed. The control and status of the reactor vessel material surveillance test coupons were reviewe The inspection in-cluded 35 hours4.050926e-4 days <br />0.00972 hours <br />5.787037e-5 weeks <br />1.33175e-5 months <br /> on site and an additional 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> at the regional offic Results: No violations were identifie ~

8506240575 850618 PDR ADOCK 05000336 G PDR

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1.0 Persons Contacted Northeast Nuclear Energy Company (NNECo)

J. Bergin, Engineer (Sleeving)

• T. Blanchard, ISI Coordinator - MS #2 S. Brinkman, Engineer (S.W. Pumps)

G. Closius, QC/QA Manager - MS#2

• J. Kelley, Superintendent, Millstone #2

• Romberg, Station Superintendent

• J. Smith, Engineering Supervisor Northeast Utilities Service Company (NUSCO)

L. Baird, ISI Coordinator H. Cote, Construction QC Supervisor R. Fuller, UT, Level III R. Michaud, Construction QC Manager

• Present at exit meeting on 5/3/8 Combustion Engineering (CE)

C. Ashman, EC, Level III ZETEC R. Miranda, EC Data Analyst 2.0 Steam Generator (SG) Tube Eddy Current Examination By the time of this inspection the eddy current (EC) steam generator tube examinations were complete although EC data analysis was still in progres The inspector observed a portion of the eddy current analysis in progress and reviewed the applicable procedure number STD-ISI-004, Revision Comparisons were made to the ASME Code Section XI, IWB 2413 and IWB2420 requirements and the intent of the NRC Regulatory Guide 1.83. The primary defect identified is pitting on the tube secondary (outside) side at a location within several inches above the upper surface of the tube shee All of the accessible tubes in both steam generators were examined in this area, to the first tube support plate, for pittin Those with pits in ex-cess of 39% through wall were scheduled for sleeving prior to continued servic The secondary side of the tubes in both steam generators were chemical cleaned as an assist in removal of the secondary side copper bearing

sludg In the opinion of this inspector, this cleaning operation has

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enhanced the EC response from existing pits or made their detection easier by removal of superfluous copper indications.

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In the sequence of eddy current data review, data is reviewed separately by two groups. The results are then compared with differences being reviewed and reevaluated. The licensee provided an independent third party review of selected portions of the eddy current evaluatio No violations were identifie .0 Steam Generator Tube Sleeving The detection of pits greater than 39's throughwall just above the tube sheet surface resulted in the decision to prepare those tubes for further service by the insertion of sleeves and hard rolling them to the tube in-side surface. The inspector reviewed the basic procedure for tube sheet sleeving and portions of procedures applicable to specific steps in the sleeving process. The training and mockup area for practice in both robotic and manual sleeving was observed. Sleeving operations in progress during the inspection including eddy current examinations to confirm that sleeving was successfully completed were observed to determine the confor-mance to applicable procedures, the level personnel training and control over the sleeving proces No violations were identifie .0 Ultrasonic Examination (UT) For Inservice Inspection (ISI)

The plant outage in progress during this inspection is the Final Examina-tion period of the first ten year ISI interva In continuation of in-spection 50-336/84-17, the progress toward meeting the 10 year interval ISI plant requirements was reviewed. The inspector noted the status of completion of examinations, schedule to meet examinations yet required and the documentation system in place to achieve the 10 year interval ISI program pla In the UT area the inspector observed examination of welds MSA-CG-16 and MSA-CG-14 as shown on drawing 25203-201-6 This UT was done in accor-dance with procedures NU UT-1 Revision 4 and NU UT-3 Revision 2 as re-viewed by the inspector. The UT observed and related activities were compared to the requirements of the ASME Code Section V, Articles 4 and 5, the ASME Code Section XI and ASNT-TC-1A. The UT test blocks for speci-fic UT data sheets were examined and data sheets, personnel qualifica-tions, the procedure of indication evaluation, significance of data sheet signoffs and the above mentioned UT procedures were reviewe No violations were identifie .0 Reactor Vessel Irradiation Material Surveillance Specimens The plant Technical Specification paragraph 4.4.9.1(c) requires that:

"The reactor vessel material irradiation surveillance specimens shall be removed and examined, to determine changes in material properties, at the intervals shown in Table 4.4-3."

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Table 4.4.-3 requires capsule W-97 be removed and examined after 3.0 ef-fective full power years (EFPY), with the next capsule (W104) scheduled for removal after 10 EFP The inspector determined that surveillance specimen removal and examina-tion is under control of the plant ISI coordinator. The first surveil-lance capsule (W-97) was removed from the Millstone Unit 2 reactor vessel in August -1980 after 3.0 EFPY. Mechanical test specimens of base metal, weld metal and weld heat affected zone provided for determination of ra-diation induced changes of both tension and impact propertie Temperature monitors, alloys with specific melting properties, indicated the irradiation temperature to be between 536F and 558 The inspector reviewed the report of evaluation of irradiated capsule W-97 dated April 1982 by Combustion Engineering, Inc., and noted that provision was made by the ISI coordinator for removal of capsule W-104 in 198 No violations were identifie .0 Service Water Intake Pump Columns - Independent Measurements The original material of the service water intake pump columns was cast iron. The cast iron was replaced with carbon steel on a temporary basis until stainless steel could be obtained. The last replacement design as installed in 1983 included type 316L flanges welded to type 316L plate rolled and welded to form cylinders with welding per the ASME Code Section I Pumps "A" and "C" operate continuously during normal conditions, which pump "B" is reserved for backup. During the 1985 outage scheduled inspection found the internal column welding of pump "C" circumferential velds had significant weld metal voids partially filled with a powder with a chemistry of 24.4% Cr, 5.4% Ni, 60.9% Fe. Pump columns "B" and "A" were removed and examined. Pump "B" had one area of one weld with a condition similar to pump "C". Pump "A" columns had no visible areas with the defective condition of pump "C".

The inspector saw a photograph of the defective condition of pump "C" columns and examined visually the column section welds of pump "A", in-cluding both the inside and outside surfaces of the longitudinal welds and the six circumferential flange to pipe welds. The longitudinal welds were noted to be nonmagnetic while the circumferential welds were slightly magnetic as typical for austenitic stainless steel weld with at least 10%

ferrit The Northeast Utilities Engineering / Materials Laboratory report

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dated March 29, 1985, by M. Galler and the purchase order for the columns I were reviewed. The pump 'B" and "C" columns have been repaired, "C" by the manufacturer and "B" at the site and examined both visually and ultra-  !

sonicall The pump "A" column flange to pipe welds are scheduled for l ultrasonic and formal visual examination. The pump manufacturer is con- l ducting an analysis of the weld proble No violations were identifie .0 QA/QC Involvement in Areas Inspected The inspector observed QA/QC personnel to be present and involved in areas covered by this inspectio Procedures used in ultrasonic examination, eddy current examination, and sleeving were noted to be reviewed by QA as part of the plant operating review committee activity in advance of performance of the actual work activitie During sleeving and eddy current sleeved tube area examination, QC personnel were present and actively involved in documentation of work steps and sequences. Level III nondestructive examination personnel were involved in both ultrasonic and eddy current examination activit No violations were identifie . Exit Meeting The inspector met with licensee representatives, listed in paragraph 1, at the conclusion of the inspection to summarize the scope and findings of the inspectio At no time during this inspection was written material provided to the licm see by the inspector.

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