ML17252B137

Letter Referring to Inspection Report 05000249/19760023 Concerning Review of Special UT Test Program for Feedwater Nozzles, Core Spray and Recirculation Bypass Inspection Results, In-Service Plan and Procedures - Dresden Unit 3

ML17252B137
Person / Time
Site:	Dresden
Issue date:	11/24/1976
From:	Heishman R NRC/RGN-III
To:	Brian Lee Commonwealth Edison Co
References
IR 1976023
Download: ML17252B137 (10)

Text

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UNITED STATES NUCLEAR REGULATORY COMMISSION

• REGION Ill.

799 ROOSEVELT ROAD GLF.:f~.ELLVN,.fLUNOIS 60137 N"OV 2 4 1976 Commonwealth Edison Company ATTN:

Mr. Byron Lee, Jr.

Docket No. 50-249

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Vice President P. O. Box 767 Chicago, Illinois 60690-Gentlemen:

i, This refers to the inspection conducted by Mr. C. M. Erb of this office on September 28-30, October 18 and November 2, 1976, of.activities at Dresden Nuclear Power Station, Unit 3, authorized by NRC Operating License No. DPR-25 and to the discussion of our

. findings with Mr. B. Stephenson at*.the conclusion of the inspection.,

The enclosed copy of our inspection report identifies areas examined during the inspection.

Within.these areas, the inspection consisted of a selective examination of procedures and representative records, observations, and interviews with personnel.

No items of noncompliance with NRC requirements were iden-tified during the courseof this inspection.

In accordance with Section 2.790 of the NRC's "Rules of Practice," Part 2, Title 10, Code of Federal Regulations, a copy of this letter and the enclosed inspection report will be placed in the. NRC's Public Document Room, except as follows.

If this report contains information that you or your contractors believe to be proprietary, you must apply in writing to this office, within twenty days of your receipt of this letter, to withhold such information from public disclosure.

The application must include a full statement of the reasons for which the information is co.nsidered proprietary, and should be prepared so that proprietary information identified in the application is contained in an enclosure to the application.

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Conunonwealth Edison Company NOV 2'11976 We will gladly discuss any que-stions you have concerning this

'i nspection.

Enclosure:

IE Inspection Report No. 050-249/76-23 cc w/encl:

Mr. B. B. Stephenson, Station Superintendent Central Files Reproduction Unit NRG 20b PDR Local PDR NSIC.

TIC Anthony Roisman, Esq.,

Attorney Sincer*ely y;ours, R. F. Hei~hman, Chief Reactor Construction and Engineering. Supp*ort Branch

• i.

UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND* ENFORCEMENT REGION III Report of Constr1:1c;tion Inspection IE Inspection Report No.

050-249/76-2~

• ,I I

4 Licensee:

Commonwealth Ed:rso*r; Company P. O. Box 767 Chicago, Illinois 60690

. I Dresden Nuclear Power Statiori, Unit 3 Morris, Illinois Type of Licensee:

Type of Inspection:

Dates of Inspection:

Princ~pal Inspector:

GE BWR 810 MWe Unannounced, Routine September 28-30, October

~~,-I 12rl 4~-.

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,.,/~-ctd~r C.

. Erb Accompanying Inspectors:

• None Other Accompan~~e Reviewed By:

• R. F. Heishman,.Chief Reactor Construction and Engineering Support Branch License No. DPR-24 Category:

C 18 and November 2, 1976 I

//-:?.J-Zd (Date) 7

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• f

SUMMARY

OF FINDINGS

. Insl?ec t ion Summary Inspection September 28-30, 1976, (Unit 3,* 76-23):

Review special UT Test program for feedwater nozzles, cor.e spray and recirculation by-pass inspection results, in-service pla~ and ~rocedures.

Inspection on October 18 and November 2, 1976, observation of ISI work,* review UT ~esults.

Enforcement Items None.

Licensee Action on Previously Identified Enforcement Items (IE Inspection Reports No. 050-237 /76-20 and No. 050-249/76-18).

The licensee QA inspector performed an audit on Midwes.t Pow.er Corporation weld rod control and found that corrective action had been implemented on temperature control of the electrode holding oven.

This matter is closed.

Other Significant Items A.

Systems and Components Nope.

B..

Facility Items (Plans and Procedures)

None.

C.

Managerial Items None.

D.

Noncompliance Identified and Corrected by Lice.nsee None.

E.

Deviations None.

F.

Status of Previously Reported Unresolved Items

1.

Unresolved Item -

(IE Inspection Report No. 050-237 /76-20)

Audit QAM-12-76-20, by*the licensee, of three welders qualifi-cation dat~ sheets which were lacking thickness and diameter 2 -

.~.

_-*e

2.

range qualifications, showed that these omissions had been corrected by the*licensee's contractor.

This matter is closed.

Unresolved Item -

(I~ Inspection Report No. 050-237/76-20)

Audit QAM-12-76-20 by the licensee has verified that weekly inspection records made by the contractor on the storage area are now on site and available for review.

This matter is closed...

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Management Interview A.

The following CECO per_soi;i.iiel ~ere involved in the management interview:

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.-*1..

B. B. Stephenson, Station Superintendent J.,~,_ Martin, Coordinator, Inse1ifvice Inspection T. Borzym,.Quaiity Assurance Coordinator B..

Matte"rs discussed and comments on the part of the management were as follows:

- 1.

2.

The inspector asked if IE Bulletin No. 76-04, relating to solution treatment of stainless piping after cold work had been implemented for Dresden Unit 3.

The licensee stated that all suspect areas had been UT examined and no defects were found.

(Paragraph 1,.Rep6rt Details)

The inspector asked about *the disposition of a surveillance sample holder which was found to be unsecured at the bottom attachment point.

This sample holder was removed and_ will not be inserted for the n~xt power production period.

(Paragraph 2, Report Detaits)

3.

The inspector asked if the 'visual examina*tion of the. feed-water Sparger units had shown up any cracks.

The licensee stated that. no defects were found during this inspection.

(Paragraph 3, Report Details)

4.

The inspector.asked if any repairs by welding were performed as a result of the inservice inspection.

The licensee stated that no defects requiring this type of* repair were found.

5.

The inspector discussed the results and disposition of UT indication found by the revised Gotti procedure in the feed-water nozzles and nozzle bores.

The licensee stated that he felt satisfactory quantita~ive results had been Becured by this UT test, and that NRR had approved another power cycle based on fracture mechaniCs.

(Paragraph 4, Report Details) 3 -

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..c*:... **

6.

The inspector asked if any rework action ~as required due to a slight distortion of the top guide rod for the reactor vessel steam dryer.

The licensee said, the guide rod did not require straightening and the dryer was ~laced in the vessel with no problem.

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REPORT DETAILS Persons.Contacted I

The following individuals in addition to those listed in the management interview were contacted during the *inspec,tion.

CowJ11onwealth Edison Company (CECO)

W. Witt, NDT Inspection-OAD T. Watts, Supervisor, Technical Group R. Mirochina, Inservice Inspection Coordinator Hartford Steam Boiler and Insurance Company (HSB)

J. Mislevy, Inspector A. Jimenez, Inspector Nuclear Services Corporation (NSC)

L. Thomas, NDT Inspection, Level III R. Chapman, NDT Inspection, Level II D. MacGill, NDT Inspection Level III.

Results of Inspection

l.

Solution Treatment of Cold Worked Austenitic Steel In response to IE Bulletin No. 7 6-04,. a review was made of* all stainless steel piping spool~ to determine if they had been pro-perly solution.* treated after cold working.

Any bent piping where heat treatment records did not clearly.indicate solution t~eatment was given a UT inspection.

The following spools were inspected and found to be acceptable:

300 System (Control Rod Drive Hydraulic System)

Spools 3-304-16 through 3-304-21 Spool 308-4A Noz?le N-18 Water Spray to Head 1300 System (Isolation Condenser)

Spool 3~1302-4 1400 System (Core Spray System)

Spool 3-1404-12 Spool 3-1404-13 L.

2.

Unsecured Surveillance Sample Holder During internals inspection a specimen holder was found unfastened from its bottom clamp.

' The installed acoustical systeTl).in the reactor vessel gave evidence during power operation, that there was a loose piece in the reactor vessel.

This holder was removed and not reinstalled for the upcoming

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cycle.

It will be installed during a future outage.

3.

Inspection of Feedwater SpaTgers

4.

The feedwater spargers were found to be*acceptable from an underwater examination.

However, four replacement spargers were fabricated up to the point of machining to the vessel opening as built dimensions.

Feedwater Nozzle and Bore Inspection by the Modified Gotti UT The "B" nozzle showed a recordable indication at 37% of* full screen

-height in the radius area of th~ nozzle.

This in~ication is compared with the 80% full screen indication from an 8 mm saw cut made in a

._calibration vessel-nozzle mockup, which was procured. by the licensee*

to establish the validity of their UT examination.

On the basis of this 37% FSH indication, the licensee maintains that this defect did not penetrate throush the cladding and into the base metal.

'J;'he "A" and "D" nozzles did not show any recor4able indications in the radiation or bore areas by the modified Gotti UT examination.

The "C" nozzle did not show any recordable indications in the radius area) but did show two recordable indications* in the bore which were

• identified as clad defects.

An h

1 f.

d b l/

ot er eye e o operation was approve y NRR-based on fracture mechanics and 25 cycles maximum of operation before the next outage.

5.

Inservice Contractors, Procedures and Qualifications Nuclear Services Corporation (NSC) performed this inservice examination for the licensee, except that T. Lambert of Lambert and Company acted as a consultant *and aided CECO in the UT testing of the four feedwater nozzles, where the modified Gatti method of UT was used.

The UT procedures were from CECO and had been approved for previous

• ISI examinations as had the calibration blocks.

All data sheets were reviewed and approved by a Level II inspector employed by the licensee.

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Letter, Karl R. Goller to R. L. Bolgar, 11/8/76.

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The following calibration UT equipment were used during this inspection:

Sonic Sonic Branson Sonic Model MK-1 Model MK-1 Model 301 Model MK-1 S/N 752311 S/N 750601 S/N 11428.

S/N 750304 All NDT procedures were qualified and approved.

NDT C-24, Inspection by QT ~f the feedwater nozzel outs~de radius and NDT-C-25, Inspection by UT of the feedwater nozzle bore area were used.

Qualifications for four Level II inspectors and two Level III inspectors were examined and found to be in order.

6.

Data Reports

• The following data reports were examined and found to be. acceptable to ASME Code Section XI.

Category Area or Part NDT Procedure Cal. Std.

G-1 91 studs and nuts - reactor UTC-14 99992.

vessel head 99994 c

Vessel to flange UTC-5 99978 c

Head to flange UTC-12*. ~.

99978 D

Nozzle to vessel. N2A UTC-5, C-10 99978 D

Nozzle to vessel N8 UTC-10, C-12.

D Nozzle to vessel N9 UTC-10, C-5 99978 F

Safe end to nozzle N2A PT-2, C-16 99910 F

Safe end to nozzle N8 UTC-16 99911 F

Safe end to nozzle N9 PT-1, C-16 99911 J

Recirculation Line 22B3 UTC-2 v

Recirculation Line 22B6 UTC-2 Supports to pipe attachment UTC-4 7

• - l

.e 2 valves internal surf~ces V-1 4 support and pipe attachments V-1 Reactor water clean up, weld No. 8-K-74 Reactor i~ternals, Vessel* ins~de surface visual underwater 8 -

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UTC-2

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