IR 05000324/1993051

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Insp Repts 50-324/93-51 & 50-325/93-51 on 931025-29.No Violations Noted.Major Areas Inspected:Isi Review of Visual Exam Data & Evaluations for Select Welds in Unit 1 Reactor Vessel Shroud
ML20058J607
Person / Time
Site: Brunswick  Duke Energy icon.png
Issue date: 11/10/1993
From: Blake J, Coley J
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20058J576 List:
References
50-324-93-51, 50-325-93-51, NUDOCS 9312140169
Download: ML20058J607 (8)


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UNITED STATES

/jaata%g NUCLEAR REGULATORY COMMISSION

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$ ) $ 101 MARIETTA STREET, N.W., SUITE 2900 ~f rn ? .p AT LANTA, GEORGIA 303234199

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Report Nos.: 50-325/93-51 and 50-324/93-51 l Licensee: Carolina Power and Light Company -!

P. O. Box 1551  ;

Raleigh, NC 27602 }

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Docket Nos.: 50-325 and 50-324 License Nos.: DPR-71 and DPR-62 Facility Name: Brunswick 1 and 2 Inspection Conducted: October 25-29, 1993 Inspector: A. . M . hku 11- 8 4 3 J. L%0oley Date Signed

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Approved by:

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J. J B7aki, Chief Date Signed '

Mat iglsandProcessesSection En indering Branch  ;

Division of Reactor Safety f

SUMMARY

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l Scope:  !

This routine, announced inspection was conducted in the areas of inservice  :

inspection (ISI) review of visual examination data and evaluations for select  !

welds in the Unit I reactor vessel shroud, review of Unit I radiographic film  !

for the residual heat removal system, review of open NRC items, and review of  ;

licensee actions regarding NRC Bulletin 80-07 and GE's Service Information

Letter (SIL) No. 330 (Jet Pump Beam Cracks). i i

Results:

In the areas inspected, violations or deviations were not identifie !

Significant improvements continued to be seen in the licensees ability to effectively manage work activities. The improvements included: integrated l team work between management and staff, extensive preparation and planning,  !

and management holding personnel accountable for successful performance. The  !

inspector also performed an inspection of the Unit I reactor building, turbine  !

building, control room, and various pump, valve, and heat exchanger room The inspection revealed significant improvements are being taken by the  :

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licensee to improve plant habitability and equipment preservatio ,

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i 9312140169 931118 PDR ADOCK 05000324  :

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REPORT DETAILS  !

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l Persons Contacted l l l Licensee Employees i R. Anderson, Vice President, Brunswick Nuclear Plant I

  • H. Beane, Manager, Quality Control ,
  • M. Bradley, Manager; Nuclear Assessment Department  !
  • J. Crider, Manager, Inservice Inspection (ISI) ,

C. Hinnant, Director, Site Operations j

  • J. Ferguson, Manager, Material and Control Stores  ;
  • R. Godly, Manager, Regulatory Programs .
  • R. Grazio, Manager, Nuclear Engineering Department l

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  • J. Langdon, NDE Supervisor  ;

l *J. Mc Gowan, Specialist, Regulatory Affairs j

  • G. Miller, Manager, Technical Support
  • J. Titrington, Manager, Unit 2 Operations i *R. Vann, Nuclear Engineering Department j *E. Willett, Manager, Project Engineering Other licensee employees contacted during this inspection included engineers, technicians, and administrative personne Other Organizations General Electric Nuclear Energy (GENE) Services J. Briggs, Level III, Visual Nondestructive Test Examiner T. Brinkman, Project Manager, Automated Ultrasonic Activities on Unit 1 Reactor Vessel Shroud E. Dykes, Manager, Nondestructive Examination (NDE) Development T. Jaschke, Senior NDE Specialist NRC Resident Inspectors
  • R. Prevatte, Senior Resident Inspector

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P. Byron, Resident Inspector M. Janis, Resident Inspector

  • Attended exit interview

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Acronyms and initialism used throughout this report are listed in the last Paragrap J Inservice Inspection (ISI) Review of In-vessel Visual Examination Data and Evaluations for Specific Welds in the Unit 1 Reactor Vessel Shroud (73755)

The licensee and General Electric (GE) are presently completing their final evaluation of the crack indications in welds for the Unit I reactor vessel shroud. These visual examinations were performed as described in i

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GE's Sll No. 572. Detail and precise examination data, correct evalua- i tions, and clear video tape records are essential for comparing present '

crack indications with future examinations results. Accurate evaluation !

of flaw lengths permit a realistic determination of flaw growth in subse- !

quent outages. In order to ensure that the licensee's records conform to '

. this criteria a review was performed on a select sample of completed visual examination data for specific reactor shroud welds and the .

moisture separator and steam dryer hold down lugs. Final video tape data '

and evaluation records for the weld areas listed below were reviewed:

Video Tape N Weld N Area Examined and Comments ,

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BNP1 93-33A H-1 Outside Di * to 180* Lower HAZ BNPI 93-33A H-1 Outside Di * to 180* Upper HAZ BNP1 93-28A H-1 Lug No. 8 75* on Shroud Outside Di BNP1 93-28A H-1 Lug No. 11 105* on Shroud Outside Di ;

BNP1 93-28A H-1 Lug No. 14 135' on Shroud Outside Di '

BNP1 93-28A H-1 lug No. 16 165* on Shroud Outside Di BNP1 93-28A H-1 lug No. 20 195* on Shroud Outside Di ;

BNP1 93-28A H-1 Lug No. 23 225' on Shroud Outside Di ;

BNP1 93-35A H-1 Outside Di ' to 174* Upper HAZ BNP1 93-46A H-6A Outside Di * to 80* Lower HAZ '

BNPI 93-46A H-6B Outside Di * to 80* Upper HAZ BNP1 93-46A H-6B Outside Di * to 180* Lower HAZ '

BNP1 - 14 H-5 Inside Di Cell 38-07, Cell 34-03, Cell 30-03, Cell 26-03, and Cell ,

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The inspector's review of data for the above areas revealed that consid-erable effort has been taken to record these data accurately. Evalua- i tions of suspect crack indication lengths appear to be conservativ )

Within the areas examined, no violation or deviation was identifie . Review of Radiographic Film and Associated Records Unit 1 (57090)

The inspector reviewed radiographic film packages and the associated radiographic inspection records for the residual heat removal welds listed below to determine whether they were prepared, evaluated, and maintained in accordance with CP&L's approved Radiographic Procedure N NDEP-101. The radiographs in each film package were also reviewed to determine whether the following examination parameters had been correctly adhered to: film quality; penetrameter type, size, placement, and sensitivity; film density and density variation; film identification; and weld coverag Weld Identification Pipe Thickness and Size i

FW-1-E11-440 16" Dia. x 0.375" Thick FW-1-E11-340 16" Dia. x 0.375" Thick FW-1-E11-339 16" Dia. x 0.375" Thick FW-1-Ell-335 16" Dia. x 0.375" Thick i

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The inspector's review of the above radiographs revealed that this film i met the acceptance criteria of the NDE procedure for technique. The '

I associated radiographic inspection records also properly documented the l interpretation and disposition of all relevant indications.

l l In addition to the above, the inspector reviewed corrective measures taken by the licensee for two weaknesses observed in the area of radio-graphic film review during an inspection reported in NRC Report No. 93- -

34. The inspector found that the licensee had taken constructive steps *

l- to insure that the reported weaknesses will not effect film qualit ,

Within the areas examined, no violation or deviation was identifie j l 4. Review of Licensee Actions Regarding NRC Bulletin 80-07 and GE's Service !

Information Letter (SIL) No. 330 (Jet Pump Beam Cracks) Units 1 and 2 (92701)

NRC Bulletin 80-07, dated April 4,1980 identified problems with failure of Jet Pump Beams in certain BWR plants due to intergranular stress [

corrosion cracking (IGSCC). GE also issued SIL No. 330 which discussed >

the beam cracks , beam inspection, and jet pump performance monitoring to detect potential problem IGSCC cracking in Inconel X-750 jet pump beams has been attributed to a susceptible microstructure (resulting from the heat treating process),

tensile stresses (resulting from the beam preload), and the environment (dissolved oxygen in the reactor coolant). Mitigation alternatives e include improved heat treatment, reduction of stresses by reducing the initial preload, and environmental changes such as hydrogen addition to ;

the reactor coolant. The licensee has been ultrasonically inspecting the jet pump beams each refueling outage with GE providing the inspection service '

As a result of a recent jet pump assembly f ailure at another utility, the inspector reviewed examination data and held discussions with the licensee and GE to determine the type of inspection techniques used, ,

transducer fixture design, and test equipment used to perform the jet pump hold down beam examinations. Discussions were also held, and documents reviewed with operation personnel concerning CP&L's method of implementing recommendations in the GE SIL for daily monitoring jet pump loop flow / recirculation pump speed ratios and establishing a jet pump performance program. In addition, the inspector reviewed the examination results for inspections performed during the past two refueling outages of Units 1 and 2. The above reviews and discussions revealed the following:

  • Hold down beams used on the jet pumps for both Units 1 and 2 do not have the improved heat treatmen '
  • CP&L's jet pump beams are loaded using the higher preload values.

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  • During the previous two outages for both Units 1 & 2, a four transducer fixture was used by GE. This fixture, however, is not the new improved four transducer fixture that GE has recently developed for jet pump l

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beam examination l

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  • During the previous two examinations conducted on Unit 2, GE did not record indications which did not exceed 20% screen height. No indica-tions were recorded by GE during these examination * During the ultrasonic examinations recently performed on Unit 1, no minimum recording levels were established. No indications were recorded by GE during these examination .
  • Operations performs a daily test to determine the operability of the reactor recirculation jet pumps inaccordance with GE SIL 330 and Paragraphs 4.4.1.2.1 and 4.4.1.2.2 of the technical specification i l

. * The licensee has recently added the cepability to inject hydrogen into

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the reactor coolan Based on the above findings, the inspector concluded that jet pump beams at Brunswick are certainly susceptible to IGSCC. However, ultrasonic inspections performed by GE for Units 1 and 2 have not detected.any problems at this point. Some limiting conditions were involved in the examinations performed by GE. However, the effectiveness of GE's NDE Procedure No. GE-UT-500 in detecting defects originating in the ligament area of the upper surface of a jet pump beam has been verified by test on an actual jet pump beam containing crack Within the areas examined, no violation or deviation was identifie ,

5. Actions on Previous Inspection Findings (92701 and 92702) (Closed) Severity Level-4 Violation 50-325/90-48-01, " Recording of Examiner Interpretations of Relevant Radiographic Indications" CP&L's Radiographic Examination Procedure No. NDEP-101, Paragraph 15.2 and Radiographic Inspection Reports for radiographs listed in Paragraph 3 of this report were reviewed by tha inspector to deter- -i mine whether CP&L radiographic examiners properly implement parag- l raph T-292 of Section V to the ASME Code. Paragraph T-292 requires '

the manufacturer to record the interpretation of each radiograph and disposition of the material examined on a radiographic interpreta- .!

tion review form accompanying the radiograph. Paragraph 15.2 of the l licensee's NDE procedure correctly requires all relevant indications as defined in the acceptance criteria to be recorded. In addition, the inspector's review of the radiographic inspection reports (RIR)  ;

for the residual heat removal system welds listed in paragraph 3 revealed that CP&L radiographic examiners do an exceptionally good job documenting their interpretations of relevant weld indication The failure of the licensee to recorded the indications' reported in

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this violation was apparently an isolated instance. However, this violation addressed a point that needs to be emphasized and that is :

no limiting conditions will be accepted by NRC on recording relevant !

indications as define by ASME acceptance criteria on the RI I (Closed) Severity Level-4 Violation 50-325/90-48-02,"Re-examination of Examiner's Welds"  ;

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The licensee's response dated March 28, 1991 acknowledged the viola- )

tion finding that an examiner had failed to identify lack of fusion !

in a weld that he had ultrasonically examined. As corrective action 1 the licensee re-examined two additional welds that the examiner had inspected and used a military sampling standard (Mil-STD-105D) as their basis for not looking any furthe In NRC Inspection Report 91-32 the licensee's corrective action was reviewed by an inspector who considered the corrective action to be inappropriate and left i the item open. The basis for the inspector not closing the item was ;

that, the examiner had only inspected seven welds during the outage -I using ultrasonics, and had missed a serious weld defect in the one l weld audited by NRC. Therefore, to insure that this was an isolated i discrepancy, all seven of the welds needed be re-examine The inspector reviewed examination documentation for the remaining 4 )

welds which had subsequently been re-examined by the licensee. No '

additional weld defects were observed as a result of the re-examina-tions performed and this item is considered close (Closed) Severity Level-4 Violation 50-325/91-32-01 and 50-324/91-32-02, " Failure to Remove Insulation During Visual ISI Inspections" The licensee's response of January 3,1991 to this notice of viola-tion was acknowledged as acceptable in NRC letter dated August 31, 1992. During this inspection, the inspector verified the corrective actions taken by the licensee as stated in their letter of respons These actions included, the re-examination of 125 bolted connec-tions, revising three procedures used for the snubber support / pipe i support inspections to ensure that the bolted portion of a pipe I clamp connection will be available for hands-on inspection (includ-ing removal of insulation), and obtaining an answer on May 22, 1992, to their Code Inquiry from the ASME Code committee. This inquiry stated, "it was the intent of Section XI, IWF -1300(e) that the !

mechanical connection for a pipe clamp includes the bolting or pins j and their interface with the clamp, and excludes the pipe to clamp '

interface". The above actions are in accordance with the licensee's letter of response and this item is considered close !

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6 (Closed) Inspector Followup Item 50-325,324/92-34-03," Welding Program"

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Based on the audit performed by the inspector and reported in NRC Inspection Report 93-13, this item is considered closed. However, i portions of CP&L's welding program will continue to be examined i'

during subsequent outages to insure that corrective measures taken by the licensee in the areas of welding and material control contin-ue to be followe (0 pen) Unresolved Item 50-325,324/93-34-01, " Traceability of Safety -

Related Replacement Parts" This item was open to track the licensee's investigation of an !

Adverse Condition Report (ACR-93-281) finding which identified that material issue room attendants were not following procedure in uniquely identifying some materials they were issuing. The inspec- _

tor's primary concern with this problem was what effect did this i failure to follow procedure have on the traceability of safety !

related replacement parts in Units 1 and 2? The licensee audited l 169 Work Requests which included 657 line item This audit found !

numerous examples where in the issue room attendants had not fol- l lowed procedure in documenting the material issue form correctl I In addition there were examples of where the procedure did not give adequate instructions. However, the licensee did not find a single example where traceability had been los In summary, 70% of the line items had traceability by heat number, of the line items not traced to specific heat numbers, the items are traceable to CP&L part numbers which bounds the purchase order and heat numbers. Therefore, the licensee did not find any indication of improper parts being issue As a result of the above audit findings, this problem will not affect Unit I re-start. It will however, remain open until all licensee actions are complete and the inspector can verify that the measures taken by the licensee are working effectivel Within the areas examined, no violation or deviation was identified.

6 Exit Interview The inspection scope and results were summarized on October 29, 1993, with those persons indicated in paragraph 1. The inspector described the areas inspected and discussed in detail the inspection results. Although j reviewed during this inspection, proprietary information is not contained ;

in this report. Dissenting comments were not received from the license l

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. , Acronyms and Initialisms  !

ACR - Adverse Condition Report i ASME - American Society of Mechanical Engineers ;

BNP - Brunswick Nuclear Project CP&L - Carolina Power and Light  ;

Dia. - Diameter  !

FW -

Field Weld GE -

General Electric l GENE - General Electric Nuclear Energy '

IGSCC- Intergranular Stress Corrosion Cracking ;

ISI -

Inservice Inspection  !

MIL - Military N Number  !

Nos. - Numbers  !

NDE - Nondestructive Examination '

NDEP - Nondestructive Examination Procedure l NRC - Nuclear Regulatory Commission  !

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Degree STD - Standard

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