IR 05000301/1996014

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Insp Rept 50-301/96-14 on 961029-970109.No Violations Noted. Major Areas Inspected:Maint & Engineering
ML20134K248
Person / Time
Site: Point Beach NextEra Energy icon.png
Issue date: 02/07/1997
From:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20134K229 List:
References
50-301-96-14, NUDOCS 9702130203
Download: ML20134K248 (10)


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~U. S. NUCLEAR REGULATORY COMMISSION REGION 111 Docket No.: 50-301 License No.: DPR-27 Report No.: 50-301/96014(DRS) i

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Licensee: Wisconsin Electric Power Company l

231 West Michigan - P379 Milwaukee, WI 53201 Facility Name: Point Beach Nuclear Plant - Unit 2 Location: Two Rivers, WI 54241

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Dates: October 29-31, November 12-15,18 21, d December 2-5,16-19,1996, January 8-9,1997 Inspectors: M. Holn' berg, Reactor inspector ;

J. SchapKer, Reactor inspector i Approved by: Wayne Kropp, Chief Engineering Specialists Branch 1 Division of Reactor Safety 9702130203 970207 PDR ADOCK 05000301 G PDR

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, Report Details e

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ll Maintenance i

l M3 Maintenance Procedures and Documentation

$ M3.1 Unit 2 Steam Generator Reolacement (SGRP)

i Insoection Scope (73753,73052,73755)

To evaluate conformance with American Society of Mechanical Engineers (ASME)

Code Section V, IX, and XI nondestructive examination (NDE) requirements, the

[ inspectors reviewed:

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e Ultrasonic examination (UT) data and flaw sizing analysis associated with

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indications detscted during the preservice examination of the Unit 2 replacement steam generator reactor coolant system (RCS) loop piping i weldr e The personnel qualifications and certifications for welders, weld operators and nondestructive testing (radiography, ultrasonic and visual) personnel i supporting SGR '

e s Radiographs for the steam generator (SG) A and B reactor coolant loop piping hot and cold leg welds, SG A ar B girth welds, and feedwater piping weld In addition, inspectors interviewed the UT examiners involved in welding activities

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on the replacement SG girth and RCS ioop weld l Observations and Findinag Based on review of personnel qualifications and certifications for welders, weld operators and NDE (radiography, ultrasonic and visual) personnel supporting SGRP, inspectors concluded that requirements of the ASME Code, Sections V and IX, 1995 Edition, had been met. Additionally, based on review of radiographs for the SG A and B reactor coolant loop piping hot and cold leg welds, SG A and B girth welds, and feedwater piping welds inspectors concluded that ASME Code, Section Ill,1986 Edition,Section V,1995 Edition requirements had been me Significant UT indications were detected in the RCS loop welds which required further evaluation for relevance. The licensee reviewed the radiographs, liquid penetrant examinations, welding data, and had contracted an engineering consultant to assess the cause of these indications. The licensee review determined that the indications were due to the ultrasonic beam redirection (an anomaly caused by grain structure at the weld metalinterface, which is prevalent for UT examinations in stainless steel welds) and not a flaw or defect la the weld, The engineering evaluation concluded that the weld was suitable for continued service. Additionally, the UT examiners were able to finger dampen the indication

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signals on the inner diameter (ID) of the weld. Thus, the inspectors concurred with

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the licensee conclusions that the weld indications were due to beam redirection.

] The licensee has scheduled the weld for examination at the next refueling outage

for further evaluation, j

I Conclusion The NDE performed, data reviewed and NDE personnel certifications for these

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examinations associated with the Unit 2 steam generator replacement met ASME l Code requirements. The licensee's decision to employ an independent engineering i consultant to review the preservice UT indications demonstrated a conservative j action to ensure the indications were not flaws, i

111. Enaineerina i

I E2 Engineering Support of Facilities and Equipment

E2.1 Insoector Uodated Final Safety Analvsis Reoort (UFSAR) Review
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While performing the inspections discussed in this report, the inspectors reviewed q

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UFSAR sections:

Section Design Basis

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j Section System Design and Operation

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Section System Safety features
Section 4.4.1 - Reactor Coolant System inspection Section 10.2 - System Design and Operation Observations and Findinos Based on review of these sections the inspectors noted the following:

Table 4.1-4 - Listed design data for e Model 44 SG that were not applicable to the replacement steam generator (REG).

Table 4.1-7 - Listed a design pressure drop of 32.2 psid for the Unit 2 SGs, vice 22.9 37.1 psid for Model Delta 47 RSG *

Section 4.2.2 - Discussed fabrication anomalies, design Codes and repair history associated with the original Unit 2 Model 44 SGs and was not applicable to the RS _ _ _ ,

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o Table 4.2-1 - Listed materials of construction applicable to the Model 44 SGs, whien had changed for the Model Delta 47 RSG Section 10.2 - A steam flow limiting device in the Unit 2 Model Delta 47 SGs was not discussed as it was for the Unit 1 SGs. SG blowdown line diameter was discussed as a 2 inch line for the Unit 2 SGs, vice a 2.5 inch line for the RSG A licensee regulatory affairs staf,f member stated that the discrepancies in the UFSAR associated with Unit 2 SGRP would be corrected during the next planned UFSAR update in June of 1997. Inspectors concluded that this would meet 10 CFR 50.71(e) requirements for timeliness of revisions updating the UFSA Conclusions inspectors identified several areas of the UFSAR which required updating with information related to the Model Delta 47 cgs installed in Unit 2. Inspectors concluded that the Licensing Departn. .s s schedule of June i997 to update the UFSAR with this information would meet 10 CFR 50.71(e) requirement E4 Engineering Staff Knowledge and Performance E4.1 Unit 2 Steam Generator Reolacement (SGRP) Insoection Scone (50001)

Steam Generating Team, Ltd. (SGT), personnel performed replacement of the Unit 2 SGs with Westinghouse Model Delta 47 SGs. The inspectors observed work, reviewed procedures, welder / weld operator personnel certifications and data associated with the following activities:

  • SGT welder qualifications and weld mock ups for the SG reactor coolant loop pipin * SGT personnel performing welding of SG A and SG B RCS hot and cold leg pipin * SGT personnel establishing pre-heat and performing welding of SG A, and SG B girth weld * SGT personnel performing welding of the SG B feedwater nozzle to nozzle i extensio {

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Weld data records, radiographs, and nonconformance reports (NCRs) for the

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^ replacement steam generator RCS loop piping and girth weld ; Additionally, inspectors reviewed the following work packages:  !

e 3061 A " Steam Generator "A" Reactor Coolant Pipe Cut and installation,"

change 11 {

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e 3061-B " Steam Generator "B" Reactor Coolant Pipe Cut and Installation,"

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e 3081-A " Steam Generator A, Mainsteam/Feedwater," change 7 i e 3081-B " Steam Generator B, Mainsteam/Feedwater," change 8

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i Observations and Findinas All SGT welding procedures used for the SG replacement were supported by

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procedure qualification records (PORs) and had been reviewed and accepted for

! Code compliance by the Authorized Nuclear Inservice Inspector (ANil), inspectors i i

performed an in-depth review of weld procedure GTNG/8.8-1PB, Revision 1, used for welding the SG A and SG B RCS hot and cold leg loop piping. The inspectors f

i concluded that the procedure met ASME Code,Section IX,1995 Edition  ;

rcquirement '

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On November 13,1996,inspectoes identified that the total shielding gas flow used for the machine gas tungsten arc welding (GTAW) of the SG A and SG B reactor coolant system hot and cold leg RCS piping was set at 400 cubic feet per hour (cfh) on the flood gas cup, with an additional 60-70 cfh set for the center gas cup j immediately surrounding the tungsten electrode. Thus, a total shielding gas flow of 460-465 cfh was used for welding, vice 10-400 cfh specified by the weld ,

procedure specification (WPS) GTNG/8.8-1PB, Revision 1. Shielding gas flow is a l

nonessential variable per QW 256 of Section IX,1995 Edition of the ASME Cod Thus, the inspectors concluded that the welding proceduro qualification remained i valid and the increased flow rate had no observed adverse affects on the welding operations. Based on differing explanations by weld operators on how to apply the

,10-400 cfh requirement in the WPS, inspectors concluded that this requirement was not being uniformly met. Inspectors' questions prompted the licensee staff to issue revision two, to WPS GTNG/8.8-1PB, which specified an allowed flow rate of i 10-400 cfh for both the center and flood cups. The failure to adhere to WPS GTNG/8.8-1PB, Revision 1, constituted a minor violation of Criterion V of l 10 CFR 50, Appendix B, and is being treated as a Non-cited violation, consistent with Section IV of the NRC Enforcement Policy (50-301/96014-01(DRS)).

The inspectors verified that weld wire spools (W005/0067 and W005/0130) and i argon shielding gas supply bottles (040392M1 and HDA91E237) used in SG A and '

SG B RCS pipe welds, were traceaole to material certifications that complied with j i

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ASME Code, Section 111,1986 Edition: Section IX,1995 Edition; and WPS requirement On NNember 15,1996, the inspectors identified a concern with the ASME Code qualification of the GTAW procedure WPS GT-SM/3.3PB, Revision 1, used on the replacement steam generator gisth welds. OW-256 of Section IX,1995 Edition of the ASME Code implemented section OW-409.1 as a supplementary essential variable for GTAW. OW-409.1 of Section IX,1995 Edition of the ASME code states "An increase in heat input, or an increase in volume of weld metal deposited per unit length of weld, over that qualified." QW-409.1 supplemental essential variables were required to be met to qualify weld procedure, WPS GT-SM/3.3PB, Revision 1, to ASME Code Section I Therefore, if an increase in heat input was used in the SG girth weld, over that used to produce the Code qualification weld, the girth weld would not meet ASME

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Code Section IX requirements as a Code qualified weld. For the girth welding operations WPS GT- SM/3.3PB, Revision 1, allowed the welding to be performed with heat inputs of up to 73.3 kilojoules per inch (kj/in). Inspectors calculated that an average per pass heat input of 55.4 kj/in had been used for making 30 GTAW pe.sses as documented in POR GT-SM/3.3-02, Revision 1, (the POR for the weld used to Code qualify WPS GT-SM/3.3PB). The licensee staff considered that OW 409.1 requirements had been met based on a single weld pass with a recorded heat input of 114 kj/in documented in POR GT-SM/3.3-Q2, Revision 1. However, the inspectors concluded that OW-409.1 requirements would not have been met c

based on the average per pass heat input (55.4 kj/in) used in the qualifying weld (POR GT-SM/3.3-02), which was less than the 73.3 kj/in allowed in the WP Therefore, the inspectors considered this weld potentially "unqual;fied" per the ASME Code requirements and considered this issue an unresolved item (50-301/96014-02(DRS)) pending further NRC staff reviews. Based on discussions with the Office of Nuclear Reactor Regulation and the Office of Nuclear Regulatory Research technical staff and reviews of NDE results (Section M3), the inspectors did not have a concem for the technical adequacy of the girth weld The inspectors noted a relatively large number cf hold or witness points in work packages associated with SGRP. An SGT quality assurance data base, which tracked hold points in work packages associated with replacement of the Unit 2 SGs, listed a total of 3073 hold points. 532 of these hold points were designated hnids for the licensee's Quality Assurance and Engineering staff. 329 witness points were also designated for the licensee's staff. This large number of hold and witness points were indicative of an active licensee staff role in oversight of the SGRP activities performed by SGT. In addition, the inspectors noted that these work packages required SGRP interferences to be marked / tagged with a pre-assigned number and then tracked on a material data sheet, until reinstallatio On November 20,1996, the licensee staff identified misalignments between the existing feedwater pipe and feedwater nczzles for SG A (1.5 in) and SG B (2.2 in).

This condition was addressed in an engineering change request (ECR) 283. The engineering staff reported that the cause of this misalignment was due to the allowable construction tolerances between the original and replacement SGs and a down-slope (reported as 0.50 in) across the plane of the girth weld. Inspectors

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found no installation checks which required the plane of the girth weld to be level.

i 1 Engineering staff,in consultation with Westinghouse staff, reported that this minor l i

offset from vertical would have no affect on SG levelindication or operation. In

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addition, the licensee identified misalignments between the existing main steam pipe and the main steam outlet for SG A (0.99 in) and SG B (1.56 in). This l condition was addressed in ECR 277 and ECR 280. Engineering staff had planned emergent system modifications for the main steam system to install a short pipe

segment at the top of each SG main steam outlet to correct for this misalignment J

and to lower the existing feedwater lines down to the level of the SG nozzle extensions to correct this misalignment. Inspectors' questions conceming the

causes of the fecd uater and main steam misalignments appeared to prompt the i

engineering staff to issue condition report CR 96-1462. Based on the ECRs and applicable safety evaluations reviewed, the inspectors concluded that the licensee's entrective actions for these misalignments were acceptabl The original weld metalin the RCS loop piping to the SG nozzle (for the removed SGs) was not completely removed in preparation for the new narrow groove wel The inspectors questioned the licensee staff concernina the potential significance of

" sensitization" (precipitation of carbides at the grain boundaries of auster.itic stainless steel) in the original weld metal caused by deposition of a new weld metal layer in the RCS loop welds, and if the POR remained valid for this application. The licensee staff stated *. hat they intended to look into this issue. The inspectors considered this issue to be an inspection followup item (50-301/96014-03(DRS))

pending further review by the NRC and the license !

The inspectors' review cf the weld data records and nonconformance reports (NCR) i identified that a welder had performed welding on the SG-B girth weld, without the required ASME Code welder qualifications. The licensee contractor had identified !

this nonconformance, and documented the problem in NCR-159. Inspectors also interviewed welderc and welding foremen concerning the use of this unqualified welder on the SG B girth weld. The unqualified welder was qualified to the ASME Code for welding with the flux core arc welding (FCAW) p ocess, which was also used for the SG girth welds. However, the welder had performed shielded metal arc welding (SMAW) on the girth weld and was not qualified to the ASME Code for ;

t!il process. The welder was qualified in the SMAW process per the American W lding Society (AWS) standards. Since the licensee intended for the replacement

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SG and associated girth welds to meet ASME Code requirements, the welders had to meet ASME Code welder qualifications. Licensee corrective actions that had been taken for this issue included: removing the unqualified welder from the SG girth welding operations, removing the unqualified weld metal, and rewelding the i SG B girth weld using ASME Code qualified welders. The licensee also reevaluated i the welder's AWS qualification to ASME and reviewed weld data records to assure there were no other unqualified welders used in any of.the welds for the SG replacement. The inspectors' review of the NCR-159 and weld documentation determined that the weld applied by the unqualified welder had been removed and replaced by qualified welders. Additionally, the inspectors' reviews of the nondestructive examinations (see section M3), confirmed that the weld quality was not affected by this nonconformance. The inspectors concluded that the licensee's corrective actions that had been taken in response to the use of an unqualified welder were complete and comprehensive. Therefore, this licensee-identified and 6 j l

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corrected problem associated with an ASME unqualified welder performing a weld on the SG-B girth weld, which is contrary to 10 CFR 50, Appendix B, Criterion V, is being treated as a Non-cited violation (NCV 50-301/96014-04(DRS)), consistent with Section Vll.B.1 of the NRC Enforcement Policy, i Conclusions i The relatively large number of engineering and quality assurance hold points throughout the SGRP work packages indicated a good preplanned licensee oversight effort. Work packages contained pre-assigned numbers for SGRP interferences, which were tracked until reinstallation and indicated a good preplanned engineering i staff effort. However, misalignments of connecting feedwater and mainsteam I piping, which required emergent system modifications to correct, indicated that the engineering staff preplanning efforts associated with SG installation alignments i were not fully effectiv l Inspectors concluded that the welding activities observed associated with the steem generator replacement met the ASME Code requirements, vvith the following possible exceptions:

  • Inspectors were concerned that a GTAW welding process used for the SG girth welds may not have met ASME Code Section IX weld procedure

% qualification requirement * Inspectors were concerned with the potential for metallurgical " sensitization" of the original weld metal, caused by deposition of new weld metalin the reactor coolant system loop welds, and the validity of the ASME Code weld procedure qualification for this applicatio j

  • The inspectors concluded that the licensee staff had taken appropriate corrective actions for a welder that performed welding on the SG B girth weld without the required ASME Code welder qualification The inspectors observations of the overall welding processes and controls during the SG replacement were good. The site manager for the SGRP was receptive to the inspectors inquiry and provided necessary contacts and responses in a timely manne V. Manaaement Meetinas XI Exit Meeting Summary At the conclusion of the inspection on November 21,1996, and January 9,1997, the inspectors met with licensee representatives identified herein and summarized the scope and findings of the inspection activities. The inspectors questioned licensee personnel as to the potential for proprietary information in the likely inspection report material discussed at the exit. No proprietary information was identifie .

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PARTIAL LIST OF PERSONS CONTACTED Wisconsin Electric Power Comoany (WEPCo)

F. Cayia, Plant Manager M. Conry, Senior Project Engineer F. Flentje, Regulatory Administrative Specialist C. Grey, Operations Manager D. Johnson, Manager, Steam Generator Replacement T. Mielke, Senior Engineer J. Scheweitzer, Site Engineering Manager T. Quay, Regulatory Services Manager Steam Generatina Team. Ltd (SGT)

M. Cepkauskas, President E. Gorden, Project Welding Engineer M. Hendricks, Quality Control Manager Hartford Steam Boiler Enaineerina and Insurance Comoany (HSB)

J. Gault, ANil U. S. Nuclear Reaulatory Commission (NRC1 g C. Keller, Resident Inspector A. McMurtray, Senior Resident lospector INSPECTION PROCEDURES USED IP 50001 Steam Generator Replacement Inspection IP 73052 Inservice inspection - Review of Procedures IP 73753 Inservice inspection IP 73755 Inservice Inspection Data Review and Evaluation ITEMS OPENED, CLOSED, AND DISCUSSED Ooened 50-301/96014-01(DRS) NCV Failure to adhere to WPS GTNG/8.8-1PB, Revision 1 50-301/96014-02(DRS) URI Girth weld ASME Code qualification 50-301/96014-03(DRS) IFl Sensitization of SG loop weld and POR validity 50-301/96014-04(DRS) NCV Unqualified welder Closed 50-301/96014 01(DRS) NCV Failure to adhere to WPS GTNG/8.8-1PB, Revision 1 50-301/96014-04(DRS) NCV Unqualified welder O

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a LIST OF ACRONYMS USED

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l A Nil Authorized Nuclear Inservice Inspector

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ASME American Society of Mechanical Engineers 2 AWS American Welding Society

! cfh Cubic feet per hour

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ECR Engineering Change Request GTAW Gas Tungsten Arc welding

{ IFl Inspection Followup Item j IP inspection Procedure

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IR inspection Report

, kj/in Kilojoules per inch NCR Nonconformance report NDE Nondestructive examination i POR Procedure Qualification Record j 3CS Reactor Coolant System i RSG Replacement Steam Generater l SG Steam Generator SGRP Steam Generator Replacement i SGT Steam Generating Team, Ltd l SMAW Shielded metal arc welding i WPS Weld Procedure Specification i

UFSAR Updated Final Safety Analysis Report

UT q Ultrasonic examination i j WPS Weld Procedure Specification

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