IR 05000454/1987009

Safety Insp Repts 50-454/87-09 & 50-455/87-13 on 870226-0414.No Violations or Deviations Identified.Major Areas Inspected:Inservice Insp Activities,Shot Peening of Steam Generator Various Mods & IE Info Notices

ML20213A394
Person / Time
Site:	Byron
Issue date:	04/21/1987
From:	Danielson D, Ward K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20213A383	List: IR 05000454/1987009 ML20213A382
References
50-454-87-09, 50-454-87-9, 50-455-87-13, IEIN-86-099, IEIN-86-106, IEIN-86-99, NUDOCS 8704270535
Download: ML20213A394 (7)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Reports No. 50-454/87009(DRS); 50-455/87013(DRS)

Docket Nos. 50-454; 50-455 Licenses No. NPF-37; NPF-60 Licensee: Commonwealth Edison Company Post Office Box 767 Chicago, IL 60690 Facility Name: Byron Station, Units 1 and 2 Inspection At: Byron Site, Byron, Illinois Inspection Conducted: February 26, March 4-6, 11, 18-20, 25-26,

-2, 7-8, and 14, 1987 Inspector:M.D. Ward IJe/7J

/ Date Approved By: D. H. Danielson, Chief 4/2'/F7 Materials and Processes Date Section Inspection Summary Inspection on February 26, March 4-6, 11, 18-20, 25-26, April 1-2, 7-8, and 14, 1987 (Reports No. 50-454/87009(DRS); No. 50-455/87013(DRS)

I Areas Inspected: Routine, unannounced safety inspection of inservice inspection (ISI) activities including review of program (73051), procedures (73052), observation of work and work activities (73753), and data review and evaluation (73755); shot peening of steam generator tubes (73051, 73052, 73753,73755); licensee action on a 50.55(e) item (92700) and IE Information Notices (92704); and various modifications (37701).

Results: No violations or deviations were identifie DOk$500$454 PDR

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DETAILS 1. P_ersons Contacted Commonwealth Edison Company (CECO)

• R. Ward, Services Superintendent

• J. Pausche, Asst. Regulatory Assurance Supervisor

• W. Walter, Asst. Technical Staff Supervisor

• E. Zittle, Regulatory Assurance Staff

• D. Flowers, ISI, Coordinator

• J. Snyder, QA Inspector R. Klingler, Project QC Supervisor R. Moravec, Project Mechanical Supervisor J. Porter, Construction Supervisor W. Witt, NDE Supervisor, Level III P. O'Neil, QC Supervisor J. Ewald, Technical Staff Engineer Nuclear Regulatory Commission (NRC)

J. Hinds, Jr., Senior Resident Inspector

• P. Brochman, Resident Inspector Hunter Corporation (HC)

S. Finch, Foreman The Babcock & Wilcox Company (B&W)

C. Meredith, Supervisor Hartford Steam Boiler Inspection and Insurance Company (HSB)

P. Fisher, Assistant Regional Manager J. Hendricks, ANII The inspector also contracted and interviewed other licensee and contractor employee * Denotes those present at the final exit interview April 14, 198 . Licensee Action on 10 CFR 50.55(e) Items (Closed) 50.55(e) Item (455/86006-EE): Westinghouse Radiographs not retrievable per code. On October 30, 1986, a potential deficiency was reported to the Region III office pursuant to 10 CFR 50.55(e). The deficiency involved misplaced radiographs for equipment supplied by Westinghouse. Based on further review of this item, CECO concluded that

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this item does not meet the reporting requirements of 10 CFR 50.55(e) as referenced in an October 29,=1986,' letter from S. C. Hunsader to

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J. G. Keppler regarding CECO's corrective actions of.the misplaced ~

radiographs. This item was reviewed in NRC Inspection Report-i No. 50-455/86038(DRS). Therefore, this 50.55(e) item is considered closed.-

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' Licensee-Action on IE Information Notices

IE information' notice No. 86-99

Degradation of-steel containments'.

This information notice was to provide licensees with.information of-a potentially significant safety problem regarding the degradation of '

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a steel containment resulting form corrosio Ceco determined that this IE-information notice.was not applicable to Byron. CECO stated that the Byron station.is.a pressurized water-reactor (PWR) plant and does not have. voids'between the steel liner

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and the concrete, therefore no action is. planned at this tim ' IE information notice No. 86-106: Feedwater line brea This information notice was to alert licensees of a' potentially generic -

problem with feedwater pipe thinning and other problems related to this even On December 9, 1986, both units at the.Surry Power Station were operating at full power when the 18" suction line to the main feedwater pump "A" for Unit 2 failed catastrophically. The event was initiated by the main steam isolation valve on steam generator-1 "C"failingclosed. Because of the' increased pressure in steam generator C" that collapsed the voids in the water,-the reactor tripped on low-low level in that steam generator. A two by.four foot section of the wall of the suction line to the "A" main feedwater pump was blown out and come.to rest in an overhead cable

, tray. The break was located in an elbow in the 18" .line about one i

foot from the 24" header. The lateral reactive force generated by i escaping feedwater completely severed the suction line. The free-

! end whipped and came to rest against the discharge-line for the

other pum i f Surveillances IBVSXII-3 and IBVSXII-4 were performed by CECO l personnel during this outag The purpose of these surveillances were to verify the structural integrity of selected secondary side piping systems by performance of ultrasonic pipe. thickness' j measurement A selection of feedwater pump suction connections i were included in the surveillance sample. These surveillances are still in progress as of April 14, 1987.

' Inservice Inspection (ISI), Unit 1

! This is the first outage of the first period of the first ten year plan.

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Ceco contracted the Babcock and Wilcox. Company (B&W) to perform the eddy current examinations (ET) on the tubes in steam generators (SG) A, B, C, and D and ultrasonic examination (UT) of the reactor vessel. Most of the remaining ISI was performed.from 3 p.m. - 11 with CECO and Westinghouse (W) performing the visual examinations. The examinations were in accordance with ASME Section XI, led 0 Cdition, Winter 1981 Addend The UT was performed by B&W using pulse-echo UT flaw detection instruments and various angles and MHZ transducers. The procedures used by B&W were reviewed and approved by a Ceco Level III who was trained and qualified by EPRI. No intergranular stress corrosion cracking (IGSCC) was identified during this outag Review of Programs, Procedures, Material, Equipment and Personnel Certifications, Audits and Data The NRC inspector reviewed that ISI programs, procedures, specific relief requests and documents relating to the following:

• Ultrasonic instruments, calibration blocks, transducers, and UT

. couplant certification * Eddy current equipment

• Liquid penetrant materials

• Magnetic particle materials and equipment

• NDE personnel certifications in accordance with SNT-TC-IA, including training and experience

• Audits and surveillances

• ISI data reports

• ET data reports on the following tubes that were plugge STEAM GENERATORS )

IRC01BA IRC01BB IRC01BC IRC01BD Row Column Row Column Row Column Row Column 1 108 3 4 3 38 29 63 28 103 20 81 24 71 31 100 32 94

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The NRC inspector observed work an'd had discussions with. personnel during the following-ISI' activities. These observations-included calibration for pipe welds and the reactor vessel welds and performance of the NDE examination The related documentation was also_ included as part-of this revie * Magnetic' particle examination'(MT) of weld IFW 87CA-6, C-1 * Liquid penetrant examination.(PT) of weld ISI 09BA-10, J * Ultrasonic examinations.(UT);of weld RC-101-BA,.S/G C-06 and' weld 1FWO300-16, C * UT, MT and PT of reactor coolant pump fly wheels 1RC01PD-and IRC01P * Immersion ultrasonic examinations being performed'from the inside surface of the reactor vessel on the nozzle to shell welds and the nozzle ta safe and piping weld * Ceco Level III training B&W personnel in UT of full penetration butt welds in cast stainless steel component * Eddy current examinations on tubes in the "A," "B,"'"C,"

and "D" stream generator No violations or deviations were identifie . Shot Peening of Steam Generator Tubes Extensive operating, experience with PWR steam generators (SGs) indicates that the roll transition area of the tubes are susceptible.to intergranular  ;

stres's corrosion cracking (IGSCC). IGSCC requires a combination of tensile stress, susceptible material, and an aggressive environment. Elimination of any one of these conditions prevents IGSCC from occurring. The purpose ,

of shot peening is to remove the tensile stress on-the ID surface'of the-

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tube and replace it with compressive stres Shop peening is a cold working process whereby an item is bombarded with round shot (in this case type 316 stainless steel) leaving the surface in a residual compressive stat The system is an automated process thereby~

providing uniformity and repeatabilit ;

The corrosion testing performed to quality this process demonstrates.that:

primary side IGSCC in the tube roll transition areas is effectivel i eliminated for the design life of the SG l Individuals involved in shot peening were. trained on a mock-up on site prior to the actual shot peening of the SG tubes. -Written and oral examinations were given to individuals prior to performing shot peenin .

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O Shot peering was performed on approximately 29" inside each tube including i.pproximately 2" above the tube sheets on the hot leg side of SGs A, B, C, and CECO and B&W personnel walked the NRC inspecar through the shot peening process in detail including the mock-up and how it operated. The NRC inspector also observed by video the shot peening process in operation on the A, B, C, and D SGs and examined the following:

A completed peened tub *

A new I-stri *

An I-strip that had been used for intensity and coverage to verify the repeatability of the proces *

Documentation of an I-strip test in the compute The NRC inspector also reviewed procedures, personnel certifications, drawings and other related documentatio No violations or deviations were identifie . Modifications Modification M6-1-85-049: Replace high pressure nitro accumulators with the low pressure instrument air (IA) genaccumulato This modification replaced the high pressure nitrogen accumulators at the pressurizer power operated relief values (PORVs) with low pressure IA accumulators. The low pressure IA air system is more compatible with the operation of the PORVs, thereby increasing the reliability of the PORV All work for this modification was performed in accordance with ASME Section XI, Class C requirements. The NRC inspector observed cutting and fit-ups including marking a pipe for a proper fit-up to a 90 elbow. The NRC inspector also heat numbers on the pipe and fittings with the documentatio Observed tacking and welding and reviewed drawings, procedures, work request and other related documentatio No violation or deviations were identified, Modification M6-1-85-0567: Addition of steam generator blow down control valves. This modification involved the addition of eight valves and was required to provide redundant isolation of the steam generator blcw down in the event of a high energy line break in the auxiliary building portion of the SD piping. These additional air operated valves will assume the control activities from the previous containment isolation valves. This will reduce isolation valve leakage caused by seat wear associated with the pressure drop across the control valv >

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i e All work-for this modification was performedLin accordance with ASME Section XI, Class B. requirements. The NRC inspector observed welding, fit-ups, and cutting; also reviewed procedures, drawings, process sheets and other related documentatio No violations or deviations were identifie Modification M6-1-86-0138: Relocation of containment isolation valves. The previous sample lines to the post accident hydrogen monitors had low point loop seals that could fill with water and became inoperable.- ~This modification pertained to the re-route'of-

' containment post accident hydrogen. monitoring sample piping. .The

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new pipe routing from the hydrogen analyzers to the containment suction sample points contained no low points to eliminated potential condensate accumulatio All work for this modification was performed in accordance with ASME Section XI, Class B requirements. The NRC inspector observed welding and fit-ups; also reviewed procedures, drawings, process sheets and related documentatio No violations or deviations'were identified.'

6. Exit Interview The inspector met with site representatives (denoted in Persons Contacted paragraph) at the conclusion of the inspection. The inspector summarized the scope and findings of the inspection noted in this report. The inspector also discussed the likely informational content of.the inspection report with regard to documents or processes reviewed by thel inspector during the inspection. The licensee did not identify any such documents / processes as proprietar l l

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