ML20082M716

Interim Deficiency Rept,Item 82 Re Adequacy of Contractor QC Insp of Pipe Supports.Initially Reported on 821201.Rept on Engineering Evaluation Performed by S&W for QA Level 1 Pipe Supports Encl.Results of Evaluation Favorable

ML20082M716
Person / Time
Site:	Fermi
Issue date:	11/28/1983
From:	Wells D DETROIT EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, 82, EF2-66480, NUDOCS 8312060246
Download: ML20082M716 (12)

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Novmber 28, 1983 EF2-66480 Mr. James G. Keppler, Regional Administrator Region III U.S. Nuclear Regulatory Ccumission 799 Roosevelt Road Glen Ellyn, Illinois 60137

Subject:

Interim Report on 10CFR50.55(e) Item on Questionable Qual-ity Control (OC) Acceptance of Pipe Hanger Installations

(#82)

Dear Mr. Keppler:

On Deceber 1,1982, Detroit Edison ccumunicated to Region III that as a result of analyses it had been concluded that a potentially reportable 10CFR50.55(e) deficiency existed involving the adequacy of contractor's quality control (OC) inspection of pipe supports.

Region III Inspector, Mr. I. Yin, investigated the matter, wtiich resulted in a " Confirmatory Action Letter" issued by Region III on December 10, 1982.

This is an interim report involving the first. two action itms of the letter, including the recently i ued final report on one of the tasks undertaken by Stone and Webster (S&W) . The task involved an engineering evaluation of pipe supports, exclusive of the inspection of strut assemblies and inspection of close-clearance and axial restraints. These inspections are being ccrapleted as separate tasks, and will be reported upon at c&pletion.

A meeting was held at the Fermi 2 site on May 20, 1983, where S&W reported to Mr. Yin the results of the inspection and evaluation of 26 percent of supports installed before December 9, 1982. Included in this report, was S&W's reccnmendation to Edison that the program be terminated because of the favorable statistical results. Mr. Yin tentatively concurred.

The attached report includes the results obtained by S&W for 53 per-cent of all safety-related supports installed before December 9, 1982. Please note that only " Attachment 2" of the attachments referenced in the S&W report is included with the copy of the report. Also, note that the inspection and engineering evaluation by S&W was terminated after 53 percent of the supports had been inspected.

8312060246 831128 PDR ADOCK 05000341 S PDR DEC - 1 1983 J62 2

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E Mr. James G. Keppler, Regional Administrator Novenber 28, 1983 EF2-66480 Page 2 If you have questions concerning this matter, please contact Mr. T.A. Alessi, Director - Project Quality Assurance.

Very truly yours,

) Ah DAW /TAA/pn cc: Mr. Richard DeYoung, Director Office of Inspection and Enforcenent U.S. Nuclear Regulatory Comnission Washington, D.C. 20555 Mr. Paul Byron, Senior Resident Inspector U.S. Nuclear Regulatory Comnission 6450 North Dixie Highway Newport, Michigan 48166

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l J.O.No. 13067.64 REPORT ON THE ENGINEERING EVALUATION OF PIPE SUPPORTS J.0.NO. 13067.64 ENRICO FERMI ATOMIC POWER PLANT - UNIT 2 DETROIT EDISON COMPANY Date Approvals:

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! 1 INTRODUCTION 1

2 . HISTORY OF EVENTS t 2

3 PROCEDURE 2

.,' h DATA, TRENDS, AND CORRECTIVE ACTIONS

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4 SAFETY OF QA LEVEL 1 PIPING SYSTEM 7

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J.O.No. 13067.64 ENGINEERING EVALUATION OF PIPE SUPPORTS 1 INTRODUCTION Stone & Webster Michigan, Incorporated (SWI) performed an Engineering Evaluation of QA Level 1 Pipe Supports for the Detroit Edison Company's Enrico lermi Atomic Power Plant - Unit 2 (EF2). This report summarizes the procedure, findings, and conclusions of the evaluation, relative to the safety of the as-installed QA Level 1 piping systems in EF2.

As a result of the engineering evaluation and Detroit Edison's commitment to specific corrective actions addressed in this report, SWI concludes that the EF2 QA Level 1 piping systems will serve their intended func-tion.

2 HISTORY OF EVENTS Detroit Edison Project Quality Assurance Department (PQA) reviewed sur-veillance reports of contractor Quality Control (QC) activities on nuclear safety-related pipe supports installed in the EF2 plant. This review resulted in a concern for the adequacy of the QC pipe support inspection. This concern was made known to the NRC - Region III. The result of the investigation that fallowed was the issuance of a con-firmatory action letter (CAL) by the NRC (Attachment 1) on Decem-ber 10, 1982.

SWI was retained by Detroit Edison to address Items 1 and 2 of the CAL, Engineering Inspection of Previously Installed Pipe Supports. From February to June 1983, under Task No. 13067.64, SWI performed an Engi-neering Inspection and Evaluation of QA Level 1 Pipe Supports installed at EF2.

In a meeting held on May 20, 1982, SWI presented to the NRC Inspector at the EF2 site the results of the inspection and evaluation of 1,841 QA Level I supports (26 percent) (Attachment 2).

SWI had established that these supports were well distributed by con-tractor, pipe size, and support type, and that the trends and results were representative of the entire 7,049 pipe supports. In this meeting, SWI concluded that, with Detroit Edison's commitment to implement the recommended corrective actions, the balance of the supports need not be reinspected.

Subsequent to this meeting, SWI and Detroit Edison jointly agreed to tersiinate this program with the firm understanding that Detroit Edison would implement and control two separate programs:

1. Reinspect 100 percent of all strut assembly installations.

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2. Reinspect all close-clearance restraints and axial restraints not reviewed by SWI. In October 1983, Detroit Edison retained SW1 to complete this task.

Deficient installations discovered by either program are t.o be repaired.

3 PROCEDURE This task was performed in accordance with the procedure outlined in SWI Project Instruction PI-22 (Attachment 3), which was reviewed and accepted by Detroit Edison PQA for QA Level I services (Attachment 4). A brief description of that procedure follows.

SWI performed and documented an engineering review and evaluation of QA Level 1 pipe supports installed prior to December 9, 1982, on the Detroit Edison EF2 project. The review included an onsite evaluation of the pipe supports by experienced pipe support engineers. The installation was evaluated against the design documents of record (sketches, DCRs, ABMs, specificati,ns, etc) using a checklist of pertinent engineering attri-butes as a guide. Deviations from the design documents were noted in the checklist. The noted deviations were evaluated on the basis af engi-neering judgment and/or calculations. All judgments rendered and cal-culations performed were submitted through Detroit Edison to the re-sponsible design organizations for their review at the completion of this task for incorporation into their calculation of record.

Deviations that were found to be unacceptable (i.e., those which prevent the support f rom serving its intended function) were documented on the checklist and on a Deviation Disposition Request (DDR) prepared by the SW1 Field Evaluation Group. The DDRs were presented to Detroit Edison PQA for issue and disposition by the appropriate design organization.

The unacceptable installations will be reworked in accordance with the disposition of the DDR, thus ensuring the adequacy of the pipe support.

4 DATA, 'i' RENDS, AND CORRECTIVE ACTIONS At the close of the program, SWI had inspected and evaluated 3,718 (53 percent) of the 7,049 QA Level 1 pipe supports. The supports were inspected for the attributes of the engineering checklist (Attachment 5).

Attachment 6 is a printout of the total data base.

SWI identified 345 supports that require enhancement to bring them within code compliance; they are listed in Attachment 7 and were dis-positioned by DDR-M-11824. Attachment 8 is a legend to be used in reading Attachments 6 and 7.

During the inspection, three generic trends were identified that require corrective action. They were:

4.1 UNQUALIFIED FILLET WELDS PROCEDURE The field welding procedure used an unqualified technique for 3/16-in.

fillet weld connecting plates with thicknesses greater than 1/2 in.

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4.2 STRUT ASSEMBLIES (PIN-TO-PIN)

Many unacceptable deviations of the installed strut assemblies (pin-to-pin) were found.

4.3 GAP CLEARANCES The. gaps on close-clearance supports and the gap between the pipe clamp and the lug on axial restraints often deviated beyond acceptable toler-ances.

SWI suggested the following specific corrective actions for the above generic problems, which Detroit Edison has implemented:

a. Unqualified Fillet Welds Procedure Detroit Edison will qualify a weld technique sheet for a 3/16-in, fillet weld for greater than 1/2-in. thick materials.

Detroit Edison's field welding engineer qualified the procedure used in compliance with AWS DI.1-75, Section 5, Part B.

b. Strut Assemblies Detroit Edison will reinspect 100 percent of all struts in-stalled and will rework defective instellations.

c. Gap Clearances Detroit Edison will reinspect the balance of all supports with engineered gaps that were not already reinspected by SWI under this program and implement corrective actions, as required.

In October 1983 Detroit Edison retained SWHI to complete this task.

5 INSPECTION ATTRIBUTES All supports were inspected using the checklist of pertinent engineering attributes (Attachment 5). However, as discussed in Section 5.8.2 of the procedure (Attachment 3), the attributes reviewed on each support were modified as generic trends and/or generic solutions developed. On April 20, 1983, SWI stopped inspection of strut-related attributes 4B and 6A through 6D. This decision was made to reflect Detroit Edison's commitment to a 100-percent reinspection of the strut assemblies (pin-to-pin).

On May 12, 1983, SWI stopped inspection of all pipe support attributes, except for gap attributes 2A and 5A through SC, This decision was based on SWI's firm opinion that only these attributes .ere of further con-cern.

On June 3, 1983, SWI stopped inspecting supports. This decision was based on Detroit Edison's commitment to inspect all the remaining sup-ports for gap attributes.

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6 NRC PRESENTATION On May 20, 1983, SWI presented to the NRC Inspector at the EF2 site the results of the inspection and evaluation of 1,841 QA Level 1 pipe sup-ports (26 percent). In this meeting, SWI recommended the termination of this task. This meeting is summarized in Attachment 2. Copies of the presentatica material are provided in Attachment 9.

SWI's conclusion that 100 percent of the QA Level 1 piping systems on the EF2 plant will serve their intended functica is based on the data presented in this meeting. Although SWI inspected and evaluated an additional 1,977 suppo: cts (27 percent) beyond those discussed in this meeting, the conclusion of that meeting is still valid for the following reasons:

1. SWI demonstrated that the sample upon which the conclusions were drawn was representative of the entire population.

2. SWI's review of the additional 1,977 supports indicated that the same trends and conclusions presented at the meeting held on May 20, 1983, have continued without change and still are valid.

7 SAFETY OF QA LEVEL 1 PIPING SYSTEM L. sod on the results of this program, and the implementation by Detroit Edison of the Corrective Action Programs recommended by SWI, SWI con-cludes, with a 95 percent confidence level, that 99.5 percer.t of all QA Level 1 pipe supports and 100 percent of all QA Level 1 piping systems will serve their intended functions.

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REPORT ON THE ENGINEERING EVALUATION OF PIPE SUPPORTS ATTACHMENT 2 NOTES OF MEETING, NRC PRESENTATION ON MAY 20,'1983 6 a mim i .

e ,4 Under Task 13067.64, Stone & Webster Michigan, Inc. (SWHI) performed an Engineering Inspection and Evaluation of QA Inval I Pipe Supports installed at the Detroit Edison Enrico Fermi - Unit 2 (EF2) power plant.

SWMI established through the use of Detroit Edison Field Banger Engineer

. Group's Pipe Support Monitoring Report (EFHR 100) that 7,050 QA I4 vel I pipe s2pports were installed and contractor QC-accepted prior to .

December 10, 1982. These 7,050 supports define the total scope of the task. he inspection and evaluation effort was conducted in accordance with a SWHI Project Instruction and SWHI Engineering Mechanics Division technical guidelines.

SWMI divided the personnel assigned to this, effort into two groups, the Field Evaluation Group and the Calculation Group. .

The Field Evaluation Group was organized into teams consisting of a primary ' team member (a pipe support engineer) and a secondary team member (an engineer or designer). He function of the Field Evaluation Group was to perform an onsite inspection of the pipe support and evaluate it against the design documents of record (pipe support sketches, design

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change requests [DCRs], as-built memoranda [ABMs], specifications, etc),

using a checklist of pertinent engineering attributes as a guide.

Deviations from the design documents were noted on the checklist. The noted deviations were evaluated based on a review of the calculation and the disposition was annotated on the checklist. Deviations requiring a more extensive evaluation were referred to the Calculation Group.

The Calculation Group consisted of pipe support engineers. They evaluated all deviatione that required a more ext'ensive review and/or the prepara-tion of supplemental calculations. ,

a he *oers of both groups received training specific for this task, as defined in SWMI's Enrico Fermi II Project Instruction.

The results of each day's inspection and the evaluation of deviations were entered daily into the computar monitoring data base. Stone & Webster Engineering Corporation's Computer Program, Pipe Banger Information i

System (PHIS, IS-202), was used to monitor the progress of this task,

! evaluate the program results, and identify trends in the data.

During the course of this task, Detroit Edison and SWMI Management reviewed the results and trends of this program and gave concurrence to all changes in task direction. Through this management involvement, the f results of this task were, presented to the NRC inspector at the EF2 site on May 20, 1983.

All deviations were evaluated by pipe support engineers and were determined to be acceptable or unacceptable. Acceptable deviations. indicate that the pipe support would serve its intended function and meet the require-ments of the governing code. As indicated above, methods of acceptance, -

including supplemental calculation number, have been clearly documented on the applicable section of the checklist. .

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Pipe supports with unacceptable deviations have been identified and will be enhanced to bring them into code compliance. Bowever, additional l

analysis 1.a,s been performed to assess the impact on plant safety had

- these deviations in the supports gone undetected. -

l First, the s'tructural and functional integrity of the support was veri-fied by allowing the support stress to' increase beyond code limits, but not to exceed yield. If the support did not pass this level of evalua-tion, the piping system integrity was verified either by reanalyzing the piping system to reflect the as-installed

• conditions, or by reanalyzing the piping system assuming that the subject support was not present. In both cases, af ter the reanalysis, the integrity of the piping system, and the pipe supports in the vicinity of the subject support, was verified.

Sumasry of Results l The results of the inspection and evaluation of 1,841 pipe supports was presented to the NRC inspector at the EF2 site on May 20, 1983. These  !

1,841 supports represent 26 percent of the 7,050 QA I4 vel I pipe / tubing '

support in the scope of this task.

SWHI has established that the supports inspected are well distributed by contractor, pipe size, and support type, and that the trends and results i are representative of the entire 7,050 pipe supports, f Of the 1,841 supports inspected. 744 supports (40 percent) had no de-viations from the design documents. Of the 1,097 supports (60 percent) with deviations from the design documen.ts, 899 were determined to serve their intended function and in full compliance with code allowables.

The remaining 198 supports with unacceptable deviations are grouped by deviation type, as follows: .

o 83 supports had deviations with the strat element o 91 supports had deviations with gaps on close-clearance frames i and/or lug-to-clamp fitup

'o 24 supports had other deviating attributes The 24 supports with other deviating attributes were evaluated for structural and functional integrity and/or systect integrity. Of the i

24 supports:

o 16 supports had their structural and functional integrity verified o 8 supports had their system integrity verified.

All 198 supports will be brough into compliance with the design documents.

Detroit Edison will establish separate programs to deal with the strut and gap situations. , .

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Conclusions Detroit Ed'ison vill establish separate programs to deal with the gap and strut situations. Recognizing this, SiMI has shown that the current program can be terminated with a 95-percent confidence level that 99.5 per-cent of the uninspected supports and 100 percent of the piping systems vill serve their intended function.

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