IR 05000301/1986021

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Insp Rept 50-301/86-21 on 861015-16,21-22,29-31,1114 & 19-20.No Violations or Deviations Identified.Major Areas Inspected:Inservice Insp Activities,Including Review of Program Procedures & Observation of Work
ML20214V661
Person / Time
Site: Point Beach NextEra Energy icon.png
Issue date: 12/05/1986
From: Danielson D, Ward K
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20214V645 List:
References
50-301-86-21, TAC-61433, NUDOCS 8612090776
Download: ML20214V661 (8)


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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Report No. 50-301/86021(DRS)

Docket No. 50-301 License No. DPR-27

Licensee: Wisconsin Electric Power Company 231 West Michigan Milwaukee, WI 52303  ;

Facility Name: Point Beach Nuclear Plant, Unit 2 Inspection At: Point Beach Site, Two Creeks, Wisconsin Inspection Conducted: October 15-16, 21-22 and 29-31, November 14 and

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19-20, 1986 M.; A M Inspector: Kavin D. Ward /MT/fd

, Date Approved By: D. H. Danielson,_ Chief / f6 Materials an'd Processe Date Section Inspection Summary Inspection on October 15-16, 21-22 and 29-31, November 14 and 19-20, 1986 Report No. 50-301/86021(DRS)

Areas Inspected: Routine unannounced inspection of inservice inspection (ISI)

activities including review of program (73051), procedures (73052), observation

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of work and work activities (73753), and data review and evaluation (73755); of the reactor internals upflow conversion (37701); of the component cooling water heat exchanger modification (37701, 55700, 57700); of-the steam generator nozzle dams modification (37701, 57700); of the fuel assembly rod examination and removal (37701, 57700); and of the reactor vessel internals visual inspection with deep sea minirover-(73052, 73753, 73755).

Results: No_ violations or deviations were identified.

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DETAILS 1. Persons Contacted Wisconsin Electric Power Company (WEPCo)

  • J. Zach, Manager
  • J. Reisenbuechler, Superintendent
  • R. Zyduck, Suoerintendent
  • J. Knorr, Regulatory Engineer
  • Pullins, Inservice Inspection (ISI) Engineer
  • Flentje, Administrative Specialist J. Schweitzer, Lead Mechanical Engineer K. Crawley, Nuclear Engineer M. Keehan, Nuclear Engineer Hartford Steam Boiler Engineering and Insurance Company R. Motquin, ANII EBASCo Services, Inc. (EBASCo)

J. Sengenberger, Level III Nuclear Regulatory Commission (NRC)

  • R. Hague, Senior Resident Inspector
  • R. Leemon, Resident Inspector The NRC inspector also contacted and interviewed other licensee and contractor employee * Denotes those present at the final exit interview November 20, 198 . Inservice Inspection. Unit 2 General

+ WEPCo contracted Westinghouse Electric Corporation (W) to perform the eddy current examinations (ET) of the steam generator (SG) tubes in accordance with ASME Section XI, 1974 Edition, Summer 1976 Addenda and 1983 Edition, Winter 1984 Addend The EBASCo and WEPCo Quality Assurance Department performed the ISI in accordance with ASME Section XI, 1977 Edition, Summer 1979 Addend * This was the first outage of the second period of the second ten year pla '

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  • Most of the ultrasonic examinations were performed by EBASCo using Ultrasonic Procedure No. PB-UT-1, Revision 2. A pulse-e-ho ultrasonic plan detection instrument and transducers from 45 - 70 were used finding no intergranular stress corrosion cracking (IGSCC). For indications which lie parallel with the weld, the size may be determined by using various angles (45 , 60 or 70 ). The EBASCo ultrasonic procedure is similar to EPRI's procedure for detecting IGSCC. Several of EBASCo's personnel were qualified at the EPRI NDE Cente b. Programs and Procedures The NRC inspector reviewed the ISI procedures and programs and found them to be acceptable. Where these rules were determined to be impractical, specific relief was requested in writing. The NRC inspector reviewed the specific relief requests including the related correspondence between the licensee and the NR c. Review of Material, Equipment and Personnel Certifications, Audits and Data The NRC inspector reviewed documents relating to the following:
  • Ultrasonic instruments, calibration blocks, transducers and UT coolant certification * Magnetic particle equipment certification * Liquid penetrant material certifications
  • NDE personnel certifications in accordance with SNT-TC-1 * Welding personnel certification in accordance with ASME Section I * Audits and surveillance * NDE report * Data from last outag * ET equipment certification * ET data reports - On S/G "A", 4,740 tubes were ET'd, 14 tubes were plugged this outage and 120 tubes were plugged previously. On S/G "B", 4,797 tubes were ET'd, 58 tubes were plugged this outage and 89 tubes were plugged previousl * Data reports - A branch connection to elbow weld No. RC-4-DR-2003-1, located in a 4" OD drain line off the loop "B" hot leg, was found to be unacceptable by UT. UT characterized the defect as 4!s" of lack of fusio The

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decisionwas-madetoremovethedefectbySemovingthewald-and associated piping and subse_quently welding'a pipe cip in.-

its place. : After welding the weld was found to be acceptable i

by liquid penetrant,. radiography and ultrasonic-examination '

The examinations provided baseline'information for future:

, examinations. )The weld'was also hydrostatically tested and 9 . found to be acceptabl ,

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'.- b j- Observation of Work Activities

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! TheNRCinspectorobse$vedworkandhaddiscussions.withpersonnel i during the ISI activities. These observations included calibratio and performance of the following NDE and documentation:

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in the "A" and "B" SG' "

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Ultrasonic examinations on reactor coolant pump "B" studs'usin j a 60 transducer through.the bore. Stud No.' 16 had an-

!. unacceptable indication.

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'* Visual examination on reactor coolant pump "B" studs. . .i j * Magneticparticleexamination(fluorescent)on'reactorvessEl j closure head stud No violations or deviations-were identifie . Steam Generator (SG) Nozzle Dams' Modifications

! WEPCo contracted Nuclear Energy. Services:(NES) to modify the.SG for the

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installation of nozzle. dam systems.in the inlet.and outlet nozzles. The

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modification consisted of welding two partial ~60* ring segments inside the SG channel head for each' nozzle. The segments are require ~d~since 1 these original SG's were designed without nozzle" rings. .The-segments

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contain the threaded. inserts which allo'w for support of the nozzle dam This provides a positive barrier between the primary coolant ~and the SG channel head. A positive barrier allows coolant levels to be independent

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of SG maintenance operation As a result,. refueling and other. activities requiring a flooded. cavity can proceed in parallel with SG work, j effectively removing the SG from the critical path.

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The NRC inspector visually examined the completed welding and reviewed-l the following documents:

F * NDE and welding procedures ,

i * Purchase orders-

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Material test reports '

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  • NDE-reports "

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  • - : Various_ correspondents

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- No. violations or deviations were identifie * '

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4. -Reactor Vessel Internals Vis.ual Inspection The NRC inspector observed the Deep Sea Minirover MKII vehicle being used by WEPCo to perform visual examinations on the reactor vessel internals in accordance with Procedure No. SMP-613, Revision 1 and ASME Section XI, 1977 Editien, Summer 1979 Addenda, Subsection 1WA-2211 and IWA-221 The MKII was equipped with a tilting, low-light level, high resolution, color TV camera in which the sensitivity was very goo A. weighted nylon rope was positioned along the reactor vessel wall in which the rope acted as a landmark to ensure that the camera was moving vertically downward along the vessel wall. The camera on the vessel was positioned so that the rope could be seen on the screen and that the underwater video delivery system (UVDS) rollers were on the vessel wal The visual examinations were performed by manipulating the camera downward along the vessel wall looking for the conditions listed below: ,

  • Cracks
  • Abnormal wear
  • Corrosion / erosion
  • Physical damage on surfaces
  • Loose parts
  • Debris
  • Loss of integrity at welded or bolted connections
  • Structural integrity
  • Detection of physical displecement
  • Structural adequacy of supporting elements
  • Connections between load-carring members
  • Tightness of bolting
  • Other indications not listed above '

, After reaching the farthest downward point of the examination, the UVDS was manipulated to the top of the vessel. The nylon rope and the camera were then repositioned to scan the adjacent section of the vessel wal The procedure was repeated until the entire vessel wall area was examined. The UVDS was manipulated around the inlet and outlet nozzles and the vessel bottom was examined by tilting the camera lens downwar No unacceptable indic:tions were found by the visual examination Also the NRC inspector reviewed the following:

  • Technical specifications of the UVD * Procedure No. SMP-61 * Drawing of vessel
  • Data No violations or deviations were identified.

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.p 5. . Reactor Internals'Upflow Conversion .

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_Since1971,some-plantswithWestinghouse'designedandmanufacturedj'

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-reactor vessel internals have experienced fuel ~ rod-failures resulting from flow induced vibration. This vibration!is initiated by reactor

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coolant ~ cross. flow-jetting through the joints between the baffle plate .In response to such an occurrence, Westinghouse conducted a comprehensive .

evaluation program which confirmed-the cause.of such fuel-damage (i.e., crossflow jetting through. baffle-joir.ts) for certain designs in some plants with-downward flow in the core barrel / baffle regio L $ .:

In order to substantially reduce the possitiility of the "Baff7e Jetting" phenomenon in such plants,' Westinghouse developed an approach whereby the reactor vessel internals are field modified.to reverse the secondar L coolant flow pattern'in the' baffle 7 barrel r.egion and reduce the jet-driving pressure differential across the baffle joints. ' This "Upflow

. Conversion"hasbeensuccessfullyinhlementedbyWestinghouse'atFarley

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Unit 1, KORI Unit 1, and tMs, outage at Point Beach Unit 2. This modification'is to be-imp 1emented.at Point Beach Unit.1 approximately April 198 .

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Westinghouse plugged 16 1.250" flow holes in the core barrel'between the

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top and second former level and Power Cutting, Inc., machined.8.2.50";ne .

flow holes in the top former plate. Implementation of these modifications '

were accomplished remotely and under water because of-the work pi'ece-being-extrem.ely radioahtiv *

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Using specially developed; remote tooling equipment, the~ barrel t0;the thermal shield annulus,# core barrel flow hole diameter, and flow hole chamfer depth were measur^ed. This data was used to. select the appropriate-plug and flange combination which were installed' utilizing special

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tooling. These operations were performed entirely underwater and were monitored by underwater TV camera ~

9 4 Plugging and drilling were accomplished in an area of limited access' and all work generated debris was controlled / collected and disposed o ;

The NRC inspector observed the activities at various times during the .

modifications and reviewed the following:

  • Program, including training program Procedure ~
  • Material certifications ,
  • Drawings- c j; '
  • Upflow licensing safety evaluation report
  • Training personnel certifications  ;
  • QA/QC personnel certifications . I No violations or deviations %ere identifie x- ,

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;- Component Cooling Water heat Exchanger Modification

Three component cooling water heat exchangers, approximately 100 feet of

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1 3" schedule 40 carbon steel piping, and supports in the auxiliary

'! steam supply system were removed because of severe tube-to-tube sheet

.' crevice ccrrosion. Four new component cooling water heat exchangers

/3 were installed in accordance with various procedures, specifications and

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ASME Section VIII, 1983 Addition, Summer 1984 Addenda, Division The NRC inspector observed various activities of the fabrication and installation of the component cooling and service water supply, return piping, valves, supports and miscellaneous appurtenances necessary to tie

.in the additional heat exchanger HX-12B. The work was performed by AZCo Hennes, In Also the NRC inspector reviewed the following:

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  • Drawings
  • NDE and welding procedures and specifications
  • Modification requests
  • Purchase requests i * Welding and NDE personnel certifications
  • Hydro / pneumatic / inservice test data sheets.

3 No violations or deviations were identifie . Fuel Assembly Rod Examination and Removal The BBC Brown Boveri Failed Fuel Rod Detection System (FFRDS) permits an operator to quickly inspect the individual rods in a fuel assembly and accurately pinpoint those with through wall defects. Through the use of a remotely controlled automatic ultrasonic (UT) detection system, the inspection can be done without having to disassemble the bundl The FFRDS ccnsisted of:

  • A flexible UT probe with transmitter and receiver to be inserted into the fuel rod row * A support frame to mount the manipulator and_to position the fuel assembly with respect to the prob * A control device for the motion of the prob * An UT system and recording devic ,

fhe FFRDS used UT pulses passing from a transmitter to a receiver. Both transmitter and receiver were attached on opposite sides of a two-finger probe which was designed to be inserted into the fuel assembly on either

, side of a row of fuel rods. The probe was inserted near the bottom of i the assembly above the lower spacer grid (skirt). When only water is j 7 . -

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present, as .was in S5-3, between transmitter and receiver, it is indicated by a certain amplitude and signal transit time of the received UT pulse signal. When a fuel rod is encountered,-the signal transit. time will be reduced due to the increased propagation velocity of the UT waves-in the metal rod compared with only water. In addition, the amplitude of tha signal is lowered due to scattering of UT waves at the fuel rod / water interfaces. If the rod is defective, then the amplitude of the signal is reduced still further by the' additional scattering caused by water inside as well as outside the rod. Thus, failed fuel rods are readily detected by simply recording the reduced amplitude of the transmitted signa When the UT probe is moved along a fuel rod row, two discrete through wall echoes are received for every fuel rod, the first from the_ front'

'balf of the fuel rod, and the second from the back hal ,

The UT pulse's between transmitter and receiver were recorded by selecting the desired evaluation range on the oscilloscope by means of an automatic gate device. As stated above, it is this reduced amplitude of the echoes which signals th'e presence of water in a leaking rod. In order to pass by the thicker guide tubes inside the fuel-rod bundles of some PWR fuel assemblies, the UT probe was of flexible design. This ensured that the fuel assemblies to be inspected were not damaged. The motion of the probe and the inspection operations were electronically controlled in both automatic and manual modes. During inspection of one row of fuel rods, any attempted manual movement of the UT probe to another row was prevented by a fail safe interlock system. In the automatic mode, the probe was automatically indexed to each successive row, returning to the starting position after completing inspection of the entire assembl The results of the inspection were plotted on an X-Y recorder and simultaneously displayed on a monitor for the operator. BBC made available the services of a Level III and a Level II UT examine The NRC inspector observed various activities on a fuel rod removed from fuel assembly P 54, using Combustion Engineering Technical Services, in accordance with their Procedures No. 17985-NSS-001 and No. 17985-NSS-002 and WEPCo Procedure No. SMP 755, Revision Also the NRC inspector reviewed the following:

  • Procedures No. WMTP 2.3 and No. SMP 755
  • Drawings
  • Data
  • Traveler for drilling i No violations or deviations were identifie . Exit Interview The inspector met with site representatives (denoted in Paragraph 1) at the conclusion of the inspection. The inspector summarized the scope and

/ findings of the inspection noted in this report. The inspector also r

discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspection. The licensee did not identify any such documents / processes *

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