IR 05000259/1992025
| ML18036A799 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 07/23/1992 |
| From: | Blake J, Economes N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML18036A798 | List: |
| References | |
| 50-259-92-25, 50-260-92-25, 50-296-92-25, GL-88-01, GL-88-1, NUDOCS 9208110152 | |
| Download: ML18036A799 (16) | |
Text
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~p8 REOII UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTASTREET, N.W.
ATLANTA,GEORGIA 30323 n
qo
+>>*<<+
'eport Nos.:
50-259/92-25, 50-260/92-25, and 50-296/92-25 Licensee:
Tennessee Valley Authority 3B Lookout Place 1101 Market Street Chattanooga, TN -37402-2801 Docket Nos.: 50-259, 50-260 and 50-296 License Nos.:
DPR-33; DPR-52, and DPR-68 Facility Name:
Browns Ferry 1, 2, and 3 Inspection Conduc d: Ju 2-26, 1992 Inspector:
N. Eco ate igned t
Approved by:
lake, Chief M terials and Processes Section Engineering Branch Division of Reactor Safety Date Signed SUMMARY Scope:
This routine, announced inspection was conducted in order to provide the inspector the opportunity'to meet with licensee and contractor personnel and discuss technical issues associated with the replacement of Unit 3 recirculation ringheader, risers, safe ends and jet pump instrumentation nozzle safe ends.
Results:
~
.
By document review, and through discussions with management and key technical personnel, the inspector ascertained that the licensee is moving forward in this project following guidelines of Generic Letter 88-01
~
9208110152 920724 PDR ADOCK 05000259
Accordingly, the licensee/contractor (GE), have generated controlling documents.
which address organization structural responsibilities, design, radiation protection, and engineering specification for procurement, pipe installation and testing activities.
In the areas inspected violations or deviations were not identifie REPORT DETAILS Persons Contacted Licensee Employees R. Baron, Licensing Manager S. Fox, Level II Examiner Radiography/Supervisor K. Groom, Welding Engineer Supervisor/Modifications E. Hartwig, Project Manager
"E. Knuettel, Licensing Engineer Unit 3
"J. Maddox, Engineering Manager
'"H. McCluskey, Vice President Browns Ferry Restart
"T. Pitchford, 'Project Coordinator, Pipe Replacement
".J. Scalice, Plant M'ariager
"O. Zeringue, Vice President, Browns Ferry Operations Other license employees contacted during this inspection included engineers, mechanics, technicians, and administrative personnel.
Other Organizations General Electric Nuclear Energy (GENE)
"R. Cameron, Manager QA/QC L. Grycko, Lead Welding Supervisor D. Harbison, Asst. Manager QA/QC V. Kenny, Project Manager QA J. Lancaster, Production Manager G. Nelson, Project Manager
"D. Porter, Manager System Modifications
"J. Rodabaugh, Piping Replacement Manager NRC Resident Inspectors
"C. Patterson, Senior Resident Inspector W. Bearden, Resident Inspector E. Christnot, Resident Inspector Attended exit interview Replacement of Recirculation Piping and Inlet Nozzle Safe Ends Unit 3, (251 2/13)
This inspection is a followup to that documented in Report 92-22.
On
e January 25, 1988 the Commission issued Generic Letter 88-01, NRC Position on IGSCC in BWR Austenitic Stainless Steel Piping.
By memorandum'44-880801804 dated August 1,
1988 the licensee committed to replace the subject piping in Unit-3 prior restarting the Unit.
Following publication of (GL 88-01), the Commission issued Revision 2 to NUREG-0313, dated January 1988, with specific recommendations and guidance for flaw evaluation per Section XI of the ASME Code, repairs of cracked piping, and pipe replacement.
By reference the licensee adopted the guidance and recommendations set-forth in the two Regulatory documents and is proceeding with plans to replace the subject components at this time.
Accordingly the licensee will replace existing intergranular stress corrosion cracking (IGSCC) susceptible material within the reactor coolant recirculation piping system with low carbon corrosion resistant austenitic stainless steel material.-
Scope of Pipe Replacement:
Essentially, the primary scope of this project is to:
(1) replace recirculation system piping from the residual heat removal (RHR), Cross-Tie up to the safe-.
ends on the N2 nozzles including the ringheader, risers and jet pump instrumentation (JPI) nozzles and associated piping, (2) replace the reactor water clean up (RWCU) system piping from the drywell penetration into the main steam tunnel, RWCU heat exchanger room and RWCU pump rooms, (3) modify the existing recirculation discharge ringheader and remove the two 22 inch flow control valves (FCV-68-33 and -35), (4) modify the two N-8 nozzle safe ends for JPI piping and remove existing drain valves, (5)'remove the Pressure Differential Indication Switch (PDIS) Sensor lines originally connected to the recirculation discharge riser pipes inside the drywell up to primary containment boundary, (6) reroute the 3/4" Recirculation Sampling piping, originally located on the'ecirculation discharge ring header between nozzles N2K and N2J, and connect it to the ring header between nozzles N2J and N2H.
'ollowing is a summary of components which are eliminated and the benefits derived by the subject pipe replacement.,
Remove valves68-530, -531, -534, -535, -536 and -539 which are associated with the two aforementioned FCV(s) removed.
Remove valves68-292, -293, -294 and -295 as they are no longer required because of the JPI nozzle safe end modification
Applicable Codes and Specifications The applicable Codes and Standards-for the pipe replacement project are:
American Society of Mechanical Engineers Boiler and Pressure Vessel (ASIVIE, B&PV) Code Sections III, V and XI 1986 Edition.
ASME, B5PV Code Section II and IX, Latest Edition.
American Welding Society (AWS) D1
~ 1-90 AWS D1.3-89 American National Standards Institute (ANSI) B31.1 1967 Edition.
American Society for Nondestructive Testing (ASNT) SNT-TC-1A 1984 (GE)
The subject modification is controlled by several engineering design change notices (DCN), issued by TVA. Of these, DCN-W17545A, Recirculation Safe End and Ringheader Replacement is central to this effort.
The inspector reviewed this document and those listed below for technical content and adequacy:
GE - Installation Specification 25A5090, "Recirculation Header and Riser Piping Replacement,"
Rev.
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GE - Installation Specification 25A102, ".Reactor Vessel-Recirculation Inlet Safe End," Rev. 1.
Ge - Installation Specification 25A5096, "Reactor Pressure Ves'sel jet Pump Instrumentation Seal Safe End," Rev.
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GE - Installation Specification 22A6049, Welding Specification for Field Modifications of Vessel Components SABFMDCN920046 Rev. 0 Safety Assessment SEBFDCN 920056 Rev. 0 Safety Evaluation As stated above and in Report 92-22, GE Nuclear Energy under contract with the licensee is responsible for procurement, fabrication, installation and testing activities required by this DCN. Accordingly GE, is the repair organization and
is therefore responsible for development and qualification of welding procedures; qualification and direct supervision of welders/welding machine operators.
GE is also responsible for quality control (QC), inspection as well as quality assurance (QA), surveillance and audits during the duration of this project. The services of an independent inspection agency (HARTFORD), have been contracted for this project.
By reference,-the reactor recirculation piping, JPI nozzle seal and reactor recirculation inlet safe-ends replacement is considered to be a repair replacement and as such it is within the scope of Articles IWA4000, IWA7000, IWB 4000 and IWB 7000 of ASME B5PV Code Section XI. Therefore, this DCN is to be performed in accordance with the requirements therein.
Welding Activities:
By review of the subject specifications and through discussion with cognizant contractor personnel, the inspector ascertained the following information on welding activities.
Welding, thermal treating and cutting were demonstrated as suitable for the project/application on mock-ups.
These demonstrations were performed within the requirements of the applicable ASME Code, Sections III, IX and XI. The majority of production welding procedures were qualified for automatic Gas Tungsten Arc Welding (GTAW) on equipment manufactured by Diametric or Arc Machine Inc. Welding qualification was done by remote control aided by video equipment.
Weld joints will be made using "K" type consumable inserts, 1/8" x 5/32".
This includes the thermal sleeve welds.
Welding procedures were qualified using a 50/50 (a 5%).Argon-Helium shielding gas mixture. The backing gas used is 99.9% high-purity argon. The shielding gas mixture is required to be welding grade or better.
Maximum heat input for welding of butt weld joints is 2.0 megajoules per cubic inch with a primary voltage of 10.0 maximum except for root passes and weld caps where this restriction does not apply.
Shielding and backing gasses will be filtered and dried as necessary to provide a maximum dewpoint at the weld of-45'.
Welding operators were required to be qualified on site using 316 NG or 316L, 0.2% maximum carbon material.
Completed welds will be nondestructively examined in accordance with ASME Sections III, V, and XI requirements as applicable.
Post-modification hydrostatic testing willbe performed per the requirements of
ASME Section XI~
Preservice and Inservice examinations will be conducted in accordance with ASME Section XI requirements.
This area will be addressed in subsequent inspections.
Other areas reviewed during this inspection included quality.
Procurement and Receiving Filler Metal Material Welding consumables required for this DCN were procured, receipt inspected and are controlled/issuedby GE in accordance with the applicable code and the aforementioned specifications.
The following tabulation identifies material for which quality records were reviewed for completeness, accuracy and compliance with applicable specification requirements.
~Te Size Heat Lo P.O.
ER308L'R309L E 309L E 309L
.035" diam. wire
~035" diam.
16" x 3/32" diam.
16 x 1/8" diam
"ER309L 1/8" x 5/32" diam, ER308L 36" x 3/32" diam.
ER308L 36: 1/8" diam.
"ER308L 1 "/8" x 5/82" diam.
XT6207 ¹2 XT6072 1MIC-1A 1 J15E-15A CT-6072 DT-581 5 T-6207 T-6117 PWMNT-9201, Item ¹
¹3
¹6
¹7
¹8
¹9
¹12
¹13
"Consumable Inserts Additional restrictions placed on these materials by the applicable specifications included minimum delta ferrite content of 8FN with no less than 5FN on any individual reading.
Field Inspections At,the time of this inspections, GE had cut and removed from the drywell all the original piping.
the inspector performed daily walk through inspections
inside the drywell to observe work in progress on each nozzle and associated piping. Work observed included machining of weld preps on thermal sleeves and certain safe-ends; mitering on T connections and machining counter bores.
Other activities observed included fitup of safe-ends to nozzles and welding on the following joints.
Weld No.
Descri tion Status RWR-3-002-G021 Cross-Tee to Ringheader Arm, Loop "B", 22" dia.
Welding out joint,
.Root RT Accepted RWR-3-002-GOIO Nozzle N2D 'to Safe-end Loop "B", 12" dia.
Welding out joint Root RT, Accepted RWR-3-002-G04 Nozzle N2 B to Safe-end Loop "B"., 12" dia.
Thermal Sleeve Weld Welding out Safe-end RWR-3-001-G025 Discharge Pipe to Tee 28" dia. x 1.425" thick, Loop "A" Weld Complete RWR-3-002-G025 Discharge Pipe to Tee 28" dia. x 1.425" thick Loop "B" Weld Complete For welds in progress the inspector observed weld metal deposition through TV monitors and checked welding parameter settings on the automatics.
Parameters checked included amperage, primary voltage, travel speed, oscillation amplitude, wire feed, and background pulse.
Other items checked included log entries describing shift activities, welder identifications, weld wire documentation, interpass temperatures checks and shielding gas flows. The dew point temperature log was reviewed to ascertain. whether parameters where being monitored, equipment (meters) were in calibration and flowgauges were. functioning satisfactorily.
Performance qualification records of welding machine operators working on the welds above were reviewed to verify their qualification status.
The programmatic a'spects of this area were documented in Report 92-22. As such, there was no effort made to revisit this area.
Radiographic Review Radiographic film of completed welds shot during this inspection were reviewed to ascertain whether film and radiographic quality was
consistant with applicable code requirements.
Welds involved in this review were as follows:
Weld No.
Size Condition RWR-3-001-'G025 RWR-3-002-G025 Nozzle N2G Weld Prep 28" x 1.425" 28" x 1.425" Nozzle Weld Prep Machined Land for Information Final Final Porosity in wdd Prep Area Undergoing Evaluation Nozzle N2J Weld Prep Nozzle Weld Prep Machined Land for Information Porosity in wekl Prep Area Undergoing Evaluation The radiographs reviewed appeared to be consistent with applicable code requirements.
Radiographic Stations 5-6 and 7-0 of weld RWR-3-001-G025 had been reshot to satisfy film density requirements.
The reshots were found to be satisfactory.
Field Deviation Disposition Reports (FDDRs)
GE(s) program uses FDDRs as a means of. documenting, evaluating and dispositioning deviations from specification requirements.
As such, the inspector reviewed a number of FDDR(s) involving machining and welding operations.
Within these areas the inspector noted that in four nozzles, machining had exceeded the final safe-end bore dimension
. requirements of 11.382 s 0.01, specified on GE drawing 101E6129 Rev. 0.
The nozzles and the bore dimensions reported following machining were as follows:
Nozzle N2D N2G N2H Bore Dimension 11.410" diameter 11.412" diameter 11.410" diameter FDDR ER3-0646 ER3-0646 ER3-0647
N
~
N2J 11.401" diameter ER3-0646 A disposition to address these deviations was being evaluated at the end of this inspection.
In addition, because these deviations appeared to be attributed to a lack'of attention of details, GE stopped operations implemented corrective measures and took strong disciplinary action against'those individuals who had responsibility for this field activity.
The inspector will revisit this area on a future inspection to evaluate results of this'action.
Within the areas inspected deviations or violations were not identified.
3.
Exit Interview The inspection scope and results were summarized on June 26, 1992, with those persons indicated in paragraph 1.
The inspector" described the areas inspected and discussed in detail the inspection results. Proprietary information is not contained in this report.
Dissenting comments were not received from.
the licensee.