IR 05000387/1995009
| ML17158A645 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 04/26/1995 |
| From: | Modes M, Patnaik P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML17158A644 | List: |
| References | |
| 50-387-95-09, 50-387-95-9, NUDOCS 9505030087 | |
| Download: ML17158A645 (7) | |
Text
U. S.
NUCLEAR REGULATORY COMHISSION
REGION I
DOCKET/REPORT NO:
LICENSEE:
FACILITY:
DATES:
" 50-387/95-09 Pennsylvania Power and Light Company Allentown, Pennsylvania Susquehanna Steam Electric Station, Unit
Berwick, Pennsyvlania April 3-7, 1995 INSPECTOR:
Prakash Patnaik, eactor Engineer Haterials Section Division of Reactor Safety Date APPROVED BY:
Hichael C. Hodes, Chief Haterials Section Division of Reactor Safety Date Areas Ins ected:
This inspection included review of the inservice inspection program, an evaluation of a computerized ISI data management system, witnessing ultrasonic examination of the core shroud, and evaluation of the results of the mechanical stress improvement process (HSIP) performed on austenitic stainless steel piping to mitigate the effects of intergranular stress corrosion cracking (IGSCC).
Results:
The inservice inspection program for the outage met the requirements of the 1989 Edition, ASHE Code,Section XI.
The activities related to inservice inspection were coordinated properly.
The management oversight in this area was adequate.
Licensee's computerized data management system was believed to enhance efficiency in data storage and retrieval, data tracking and gA review.
The core shroud inspection was conducted in accordance with the ultrasonic examination procedure, whi,ch was proven to be satisfactory at other facilities.
The results of HSIP performed on five welds indicated that the process met the requirements of the engineering specification.
Susquehanna is implementing Code Case N-509 and Case N-524 before they are reviewed for acceptability by the NRC staff listed in Regulatory Guide 1. 147.
9505030087 950426 PDR ADOCK 05000387
U. S.
NUCLEAR REGULATORY COMMISSION
REGION I
DOCKET/REPORT NO LICENSEE:
FACILITY:
DATES:
50-387/95-09 Pennsylvania Power and Light Company Allentown, Pennsylvania Susquehanna Steam Electric Station, Unit
Berwick, Pennsyvlania April 3-7, 1995 INSPECTOR:
Prakash Patnaik, Reactor Engineer Haterials Section Division of Reactor Safety Date APPROVED BY:
Michael C. Modes, Chief Materials Section Division of Reactor Safety Date Areas Ins ected:
This inspection included review of the inservice inspection program, an evaluation of a computerized ISI data management system, witnessing ultrasonic examination of the core shroud, and evaluation of the results of the mechanical stress improvement process (HSIP) performed on austenitic stainless steel piping to mitigate the effects of intergranular stress corrosion cracking (IGSCC).
- Results:
The inservice inspection program for the outage met the requirements of the 1989 Edition, ASHE Code,Section XI.
The activities related to inservice inspection were coordinated properly.
The management oversight in this area was adequate.
Licensee's computerized data management system was believed to enhance efficiency in data storage and retrieval, data tracking and gA review.
The core shroud inspection was conducted in accordance with the ultrasonic examination procedure, which was proven to be satisfactory at other facilities.
The results of HSIP performed on five welds indicated that the process met the requirements of the engineering specification.
Susquehanna is implementing Code Case N-509 and Case N-524 before they are reviewed for acceptability by the NRC staff listed in Regulatory Guide 1. 14 DETAILS 1.0 INSERVICE INSPECTION (ISI) (73753)
1.1 Scope
, The conduct of inservice inspection using ultrasonic, magnetic particle and liquid penetrant examination methods ensures integrity of the pressure boundary.
During the NRC inspection of Susquehanna, Unit 1, the following items were covered:
A review of the current inservice inspection ( ISI) program enumerated in the ISI plan for the second 10-year interval, including the scope of nondestructive examination for Class 1, 2, and 3 components during the eighth refueling outage;
~
An evaluation of a newly-installed computerized ISI data management system;
~
'A review and evaluation of sample inservice inspection data;
~
Witness of the ultrasonic examination of the core shroud;
~
A review of results of the mechanical stress improvement process (MSIP)
performed on selected welds-to mitigate stress corrosion cracking.
~
Surveillance of nondestructive examination of high-pressure turbine rotor blades.
1.2 Findings For both units of Susquehanna, the second 10-year inservice inspection interval commenced on June 1,
1994.
To make this effective, the licensee chose to alter the Unit 1 and the Unit 2 first inspection intervals to allow for a mutual end date of June 1,
1994.
Accordingly, the Unit 1 first inspection interval was extended from its original completion date of June 8, 1993, to June 1,
1994, and the Unit 2 first inspection interval was shortened from its original completion date of February 12, 1995, to June 1,'994.
This is in accordance with the requirements of the American Society for Mechanical Engineers (ASME) Code,Section XI, Paragraph IWA-2400.
Both units have adopted the ASME Code,Section XI, 1989 Edition for inservice inspection.
A review of the program indicated that the licensee has utilized ASME Code Case N-509 for the examination of Class 1, 2, and 3 component supports and Code Case N-524 for the examination of longitudinal welds in Class 1 and 2 piping.
These code cases have not been accepted by NRC staff in Regulatory Guide 1. 147, Rev.
11, "Inservice Inspection Code Case Acceptability."
Hence, the licensee has taken the risk of having to augment examination of affected components for code compliance in the future, should the code cases not be acceptable to the NRC staf The inspector believes the utilization of the code cases has no substantial impact on public health and safety within the scope of the examination.
A review of the outage scope for components selected for examination indicated that the examination plan complied with the 1989 edition of the ASHE Code,
,Section XI, in all other aspects.
The licensee has incorporated a new data management system for inservice inspection.
The new system, called the
"IDDEAL" system for ISI data management, is extremely adaptable and has a user-friendly software program interface.
The inspector had a demonstration of the capabilities of this system and noted the following features:
~
The system allows import of the existing mainframe-based 10-year'lan into IDDEAL for easy access to outage data for update, edit, or expansion and allows printing the entire or selected portions of the inspection plan.
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'The data sheets can be customized into the IDDEAL program permitting data entry directly into the system for digital archiving and statistical processing.
~
All calibration records can be scanned along with input of calibration data to provide on-screen audit or review of records.
All personnel certification records can be scanned to provide on-screen audit or review of personnel records.
For each component, the NDE procedure to be used, including the calibration block and an isometric sketch of the line containing the item to be inspected, can be printed out.
All inservice inspection data can be reviewed, including disposition of indications and status of inspection.
The inspector believes the use of the computerized data management system will enhance efficiency in data storage and-retrieval, data tracking, gA review and real-time reporting capabilities.
The inspector reviewed manual ultrasonic examination data on the following welds for reactor recirculation piping.
Weld Nos.
Location Results VRRB 311-14-P VRRB 311-FW-A3 VRRB 311-10-L VRRB 311-10-M Valve to pipe weld Pipe weld Elbow to pipe weld Pipe weld No recordable indication No recordable indication No recordable indication No recordable indication Records of UT instrument qualification (linearity check)
and the calibration o
of equipment are available for review and were satisfactor Also reviewed, the data on the automated ultrasonic examination of the reactor vessel bottom head to shell weld, identified as AA.
The evaluation level was 20/ of DAC.
There were no relevant indications.
The inspector witnessed a
video presentation of the in-vessel inspection of the steam dryer.
The resolution on the screen was half a mil on the gray scale.
This inspection identified a crack in the steam dryer channel weld DC-A-1.
The crack was located in the lower weld of an 8"x 8"x 0.25" plate directly below the zero degree seismic bracket lug.
The crack ran horizontal, starting at the interface of the weld for up to 8".
The indication was documented in a condition report that would be dispositioned prior to returning the unit to service.
The inspector witnessed ultrasonic examination of the core shroud welds H-3 and H-4.
This examination was automated with "Smart 2000 OD Tracker,"
utilizing a 45'hear wave, an OD creeping wave, and a 60'efracted longitudinal search unit.
The examination was conducted using contractor's procedure GE-ISI-447, approved by the licensee.
I The written practice for qualification and certification of nondestructive test personnel of the licensee, complied with the requirements of SNT-TC-IA, 1984 Edition, and the additional requirements of the ASNE Code,Section XI, 1989 Edition.
A review of sample certifications of the contractor and the licensee's NDE personnel did not reveal any discrepancy against their written practices.
The inspector reviewed the procedure and the technique for the mechanical.
stress improvement process (HSIP)
used by the licensee to mitigate intergranular stress corrosion cracking (IGSCC) of stainless steel piping.
The NSIP is believed to produce compressive stresses at the inside diameter of the weld by mechanical means via a hydraulically-operated mechanical clamp used to contract the pipe on one side of the weld.
The results of HSIP performed on the following welds were reviewed for compliance with the engineering specification.
Weld No.
S stem Pi e Si ze DIA DCB-102-1-FW-1 DCA-110-1-FW-1 DBB-107-1-1-B N5B Nozzle N5A Nozzle Reactor Vessel Head Spray Residual Heat Removal Residual Heat Removal Core Spray Core Spray 6 inches 24 inches 24 inches, 10 inches 10 inches The inspector found that the change in the circumference of each weld was acceptable in accordance with the engineering specification.
Each weld was ultrasonically examined following HSIP, and there was no evidence of cracking as a result of the remediation.
During a site surveillance, the inspector witnessed magnetic particle inspection of the diaphragm of the high pressure (HP) rotor of the Unit
turbine.
The examination was conducted using the wet fluorescent magnetic particle method.
The personnel performing the examination were knowledgeable of the technique specified in the Examination Procedure No. 94-TCI-101, I
Rev.
0, was verified during surveillance.
The inspector reviewed a sample of test results of magnetic particle examination of the HP turbine blades.
The following blades were reported to have indications.
Stage No.
Turbine
Turbine
Turbine
Turbine
Generator
Blade No.
38
116
Indicat i on Linear Linear Linear Linear Linear (Ding)
Size I/>>
1/II 1/<<
5/32-'A" 5/32" From TIP q/n 4)/II g/ II 4'/4" 8" down Location Ed e 1'/4"
'/4" (TE)
'/4"~/i" (TE)
(TE)
1'/4" (LE)
Side Outlet
Outlet
Outlet
Outlet
Inlet TE
= Trailing Edge; LE = Leading Edge
- The indications on outlet side of blade are measured from the trailing edge.
The licensee stated that the above indications would be dispositioned prior to return of the unit to service.
2.0 tttANAGEMENT OVERSIGHT AND SELF-ASSESSMENT The Nuclear Assessment Services (NAS) performs audits and surveillances of the inservice inspection program and'the activities.
The audit by licensee's management performed in May 1994 evaluated the adequacy of the inservice inspection program in meeting the ASME Code,Section XI and the licensing commitments and also the effectiveness of program controls for performing inservice inspection.
Licensee's audit revealed that the ISI program and the implementing procedures adequately addressed the ASME Code requirements and other licensing commitments.
The implementation of the program and procedures was found to be effective and provided the required documentation to evidence the performance of inservice inspections, as well as resolution of anomalies noted during the conduct of the inspections.
The inspector believes the management oversight of the ISI program has met its goal, and their self-assessment was appropri ate.
3.0 ENTRANCE AND EXIT MEETINGS Members of the licensee's management and engineering staff were informed of the purpose of the inspection at the entrance meeting, which took place on April 3, 1995, and the findings of the inspection were presented to, and discussed with, members of the management at the exit meeting, conducted on April 7, 1995.
The licensee concurred with the findings of the inspection.
A list of attendees at the exit meeting is attached to this report as Attachment 1.
Attachment:
Exit Meeting Attendees
ATTACHMENT I EXIT MEETING ATTENDEES Penns lvania Power and Li ht H.
G.
R. A.
K. V.
T. C.
G. J.
G.
D.
H. J.
T.
K.
H. L.
R.
R.
Stanley Baker Chambliss Dalpiaz Kuczynski Miller Palmer Steingass Webb Wehry Vice President, Nuclear Operations Coordination Engineer, NgA Manager, Nuclear Operations Manager, Nuclear Maintenance Manager, Plant Support Manager, Nuclear Technology Manager, NSE Supervisor, ISI Supervisor, Maintenance Technology Licensing Engineer