CP-201500775, Relief Request B-3, Second Ten Year Inservice Inspection Interval from 10CFR50.55a Inspection Requirements Due to Physical Interferences (1998 Edition of ASME Code, Section XI, 2000 Addenda Second Interval Start Date: August
| ML15224B361 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 08/03/2015 |
| From: | Flores R, Madden F Luminant Generation Co, Luminant Power |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CP-201500775, TXX-15115 | |
| Download: ML15224B361 (7) | |
Text
SRafael Flores Lurninant Power Senior Vice President P0O Box 1002 Chief Nuclear Officer 6322 North FM 56 Rafael.Flores@Luminant~com Glen Rose, TX 76043 Lu minant 25487550 CP-201500775 Ref. # 10CFR50.55a(g)(5)(iii)
TXX-15115 August 3, 2015 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555
SUBJECT:
COMANCHE PEAK NUCLEAR POWER PLANT DOCKET NO. 50-446 RELIEF REQUEST B-3 FOR UNIT 2 SECOND TEN YEAR INSERVICE INSPECTION INTERVAL FROM 10CFR50.55a INSPECTION REQUIREMENTS DUE TO PHYSICAL INTERFERENCES (1998 EDITION OF ASME CODE, SECTION XI, 2000 ADDENDA SECOND INTERVAL START DATE: AUGUST 3, 2004 SECON1D INTERVAL END DATE: AUGUST 2, 2014)
Dear Sir or Madam:
Pursuant to 10 CFR 50.55a(g)(5)(iii)), Luminant Generation Company, LLC (Luminant Power) is submitting Relief Request B-3 (see attachments) for Comanche Peak Unit 2 for the second ten year inservice inspection interval. Luminant Power has determined that certain inspection requirements of ASME Section XI are impractical due to physical interferences.
The geometry of the reactor coolant piping to the flange makes the Code required examination coverage requirements impractical. Ultrasonic Testing (LIT) of the subject welds was performed during the second interval to the maximum extent practical based on design configuration restrictions. Pressure test VT-2 visual examinations were also performed with no evidence of leakage identified for the subject component. No undue risk to the public health and safety is presented by this request.
This communication contains no new licensing basis commitments regarding Comanche Peak Unit 2.
U. S. Nuclear Regutatory Commission TXX-151 15 Page 2 of 2 08/03/2015 Should you have any questions, please contact Mr. Jack Hicks at (254) 897-6725.
Sincerely, Luminant Generation Company LLC Rafael Flores
/Fred W. Mvadden Director, External Affairs - Relief Request B-3 for Unit 2 Second Ten Year ISI Interval from 10CFR5O.55a Inspection Requirements due to Physical Interferences - Examination Data Sheets and Sketch (3 pages) c -
Marc L. Dapas, Region IV Baiwant K. Singal, NRR Resident Inspectors, Comanche Peak Rob D. Troutt, TDLR Jack Ballard, ANIT, Comanche Peak to TXX-15115 Page 1 of 2 COMANCHE PEAK NUCLEAR POWER PLANT UNIT 2 Relief Request Number B-3 for Unit 2 Second 10 Year ISI Interval From 10CFR50.55a Inspection Requirements due to Physical Interferences (Second 10-Year ISI Interval Start Date: August 3, 2004; End Date: August 2, 2014)
- 1.
ASME Code Component Affected:
Class 1 Risk-Informed Inservice Inspection (RI-ISI) piping weld as shown:
RI-ISI Piping Weld (formerly Code Category B-T)
Code Cat / Item No.
Description Weld No.
(Note)
R-A, R1.11 6' pipe to pipe flange TCX-l-4105-6 Note: As the methodology in EPRI TR-112657 Rev. B-A does not provide item numbers; the format in ASME Code Case N-578-1 is used for the assignment of this number.
- 2.
Applicable Code Edition and Addenda
The applicable ASME Boiler and Pressure Vessel Code (hereafter referred to as the "Code")
edition and addenda is ASME Section XI, "Rule for Inservice Inspection of Nuclear Power Plant Components," 1998 Edition, through 2000 Addenda. In addition, as required by 10CFR50.55a, ASME Section XI, 1995 Edition, 1996 Addenda is used for Appendix VIII, Performance Demonstration for Ultrasonic Examination System.
- 3.
Applicable Code Requirement
ASME Section XI, Figure IWB - 2500-8(c) 1998 Edition through 2000 Addenda requires volumetric examination of a minimum volume of the inner 1/3 t (one third of the thickness) extending into the piping base metal for a distance of 1/4" past the edge of the weld crown for NPS 4" and larger.
In a letter (NRR 10580) dated October 5, 2006, from the NRC to Comanche Peak Steam Electric Station, Unit No. 2, the NRC approved in relief request A-i the extension of risk-informed inspection (RI-ISI) program for ASME Code Class 1 and 2 piping for the second interval. The methodology in EPRI TR-112657 Rev. B-A is used as the examination method as well as the selection of welds to be examined. The RI-ISI program requires volumetric examination of the subject weld and extends the Code required volume of the inner 1/3 t to 1/2" past the edge of the weld crown if no counterbore is present or a distance of 1/4" on either side of the weld counterbore.
The Comanche Peak Nuclear Power Plant (CPNPP) second ten-year interval Inservice Inspection Program Plan also implements Code Case N-460, which is endorsed by the NRC in revision 14 of Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability ASME Section XI, Division 1." Code Case N-460 states in part, when the entire examination volume or area cannot be examined due to interference by another component or part geometry, a reduction in examination coverage on any Class 1 or Class 2 weld may be accepted provided the reduction coverage for that weld is less than 10 percent.
NRC Information Notice (IN) 98-42, "Implementation of 10CFR50.55a(g) Inservice Inspection Requirements," termed a reduction in coverage of less than 10 percent to be "essentially 100 percent. "TN 98-42 states in part, 'The NRC has adopted and further refined the definition of to TXX-15115 Page 2 of 2 COMANCHE PEAK NUCLEAR POWER PLANT UNIT 2 Relief Request Number B-3 for Unit 2 Second 10 Year IS1 Interval From 10CFR50.55a Inspection Requirements due to Physical Interferences (Second 10-Year 1SI Interval Start Date: August 3, 2004; End Date: August 2, 2014)
"essentially 100 percent" to mean "greater than 90 percent"... has been applied to all examinations of welds or other areas required by ASME Section XI.'
- 4.
Impracticality of Compliance:
The geometry of the subject component limits the examination to one side, dlue to the pipe flange welded to the pipe. Volumetric examinations were performed with shear wave search units with nominal angles of 45 and 60 degrees. Coverage obtained was 100% in the two circumferential directions, and 100% in the upstream; however, downstream scan could not be taken due to the pipe flange. Thus, the coverage is limited to 75% as shown in Attachment 2.
The examinations were conducted in accordance with procedure TX-ISI-302, "Ultrasonic Examination of Austenitic Piping Welds."
- 5.
Burden caused by Compliance:
The design configuration restrictions of the subject components make the Code required examination coverage requirements for the weld volume impractical. Plant modifications or replacement of components designed to allow for complete coverage would be needed to meet the Code Requirements. This would cause considerable burden to CPNPP.
- 6.
Proposed Alternative and Basis for Use:
Proposed Alternative:
The following alternatives are proposed in lieu of the required examination coverage of essentially 100 percent:
- 1.
Ultrasonic testing (UT) of the subject component weld was performed to the maximum extent practical during the second ten-year interval.
- 2.
Pressure test VT-2 visual examinations were performed, as required by Code Category B-P, during the second ten-year interval. No evidence of leakage was identified for this component.
Basis for use:
The basis for use of this alternative is that it provides the best examination coverage practical within the limitations of the current configuration. Based on the percentage of the examination volume completed and the lack of any indications identified, there is a high level of confidence in the continued structural integrity of the weld. CPNPP believes that there is no undue risk to the public health and safety presented by this request.
- 7.
Duration of Proposed Alternative:
The second ten-year ISI interval for Unit 2 began on August 3, 2004 and ended on August 2, 2014.
- 8.
Precedents:
None
0 Attah met 22o T)(X-15115 93 PDI Calibration Data Sheet Plant/Unit COMANCHE UNIT 2 Company WESDYNE Comp/System RC PRESSURIZER SAFETY Procedure No.
TX-ISI-302 RevlChng. No.
21! N/A Cal. Block No.
PDI-03 Cal. Block Temp. 710*. Comp.Temp.
87° Therm S/N TU 2261 Size 6,0" Sch.
160/.719 0T'"
r--1 Ferritic
[X] Austenitic Data Sheet #
9UT1 lB Page of Cal. Checks Time Initial Calib.
1030 Initial Calib. Date 10/12/06 Intermediate 1110 Intermediate 1150 Final Calib.
1231 Final Calib. Date 10/12/05 0
2
'4 6
8 CRT Div. =
0.24 80 l.a 60----------------
0 2
4 6
8.
CRT Div. =
0.38 Cal.Direction Scan Area:
Axial Circ. X Both J.
to Weld X
II to Weld X
Couplant Type:
ULTRAGEL II Batch:
06225 Access Recordable Indications Yes Noiw Geom Exam Sens.
Examination Area/Weld TCX-1-4501-1 1 1 SIDED_
lX 450-32.3 dB
__________________ SDED60RL 0-58.0 dB Remarks/Reasons for incomplete Scan(s)
FSH: ROMPAS BLOCK (SAP 102363) 75% CODE COVERAGE ACHIEVED Search Unit #1 Manufacturer:.
KBA Serial No.:
00YH5F Freg.:
2.25Mhz Size:
0.5" Shape:
ROUND Exam Angle:
45°S Model:
COMP G Measured Angle:
450 Wedge Style:
MSWOC Search Unit Cable Type:
RG 174 Length:
6' No. of Connecters 0
Instrument Settings Make/Model:
KBA / USN 52R Serial No:
SAP 102249 Search Unit #2 Manufacturer:.
MEGASONICS Serial No.:
50240 Freg.:
2.25Mhz Size:
2X (.25 x.so) Shape:
RECT Exam Angle:
60=RL Model:
CGD Measured Angle:
610° Wedge Style:
INTRAGRAL Search Unit Cable Type:
RG 174 Length:
6' No. of Connecters 0
Instrument Settings Make/Model:
KBA / USN 52R Serial No:
SP 1022,49 DisDelay:
0.oo0 ps Range:
3.801 Prb.Delay:
7.286 ps Pwidth:
FIXED M'tl CalNel:.2349 jis Pulser:
DUAL Damping:
1000 fi Reject:
0%
Rep. Rate:
HIGH Freq.:
2.0 -8.0 Filter:.
FIXED Dual:
N/A Voltage:
FIXED Rectify:
FULLWAVE Reference Sensitivity (Sens.)
Axial:
54.8 Db Circ.
N/A SDH Sensitivity:
N/A Examiners:
WALLACE W. REID Level Examiners:
N/A Level II Date 10/12/06 N/A Date N/A Dis.Delay:. 0,00o ps Range:
2.392 Prb.Delay. 6.349 ~is Pwidth:
FIXED M'tl CalNeh:.1231 its Pulser:
SINGLE Damping:
1000
- ) Reject:
,0%
Rep. Rate:
HIGH Freq.:
2.0 - 8.0 Filter:
FIXED Dual:
N/A Voltage:
FIXED Rectify:
FULLWAVE
- Reference Sensitivity (Sens.)
Axial:
14.3 Db Circ.
14.3 Db SDH Sensitivity:
N/A FUrther Evaluationi Needed?
livIes I)(]
No' (ldwer/ Ioi Ial Reviewer I Daic
/ 01/4/6 1~
,,/1
/-
lt~tt, ;,
'.1
, eTXX-1 5115 2oj*3 PROFILE OF THE EXAMINATION REPORT NO.
9UTll1 STATION COMANCHE PEAK UNIT 2
PAGE 2..
OF SYSTEM PRESSURIZER COMPONENT PIPE TO FLANGE DRAWING NO.
TCX-I-4S01 IDENT NO.
11 PROFILE SECTION DIAMETER 6'
WELD LENGTH 21" CROWN WIDTH 1,0" CROWN HEIGHT FLUSH LONG SEAM LOCATION(S)
N/A CENTERUNE WELD PIPE FLANGE (Thickness in inches)
.72
.72
.72
.80
.82
.80
- 90 N/A N/A
- ii 1 /""
÷1"
+ 1/2" TOE CUM.
TOE
.11?2
÷ 1
+ 1 1/2" UPSTREAM FLOW DOWNSTREAM MAEASURlEMENIS STAR1T AT C/I OF THE WELD, THIEN TOE OF WELD AND r
"[~~HEN I/2" FROM TOE, V
1 AND.4 1/2" ON BOTHI SIDE OF WELD AS AJ'PUCADLF-PROFILE EXAM COMMENTS PROFILE TAKEN ATO0° COVERAGE ACHIEVED SECTION XI X
RISK INFORMED X
AUGMENTED N/A PREVIOUS DATA REVIEWED YES TYPE UT EXAMINER WALLACE REID DATE 10/12106 EXAMINER (AJ)/_g DATEJJL)[
REIEER/
(r*
tS~D T
I4 EIWR 6~%7~DTJ2J/~
to TXX-1 5115 3o 3 of 3 LIMITATION TO EXAMINATION REPORT NO.:
9UT11 B QPAGE
~OF~
PLANT COMANCHE PEAK UNIT 2
SKETCH TCX-1 -4501 SYST./COMP.
RC PRESSURIZER SAFETY PROCEDURE TX-ISt-302, Rev. 2 EXAMINER WALLACE W. REID DATE 10/12/06 RELATED TO:
UT X
PROVIDE GENERAL INFORMATION TO DESCRIBE APPROXIMATE SIZE,. LOCATION AND) TYPE OF LUMITATION.
US SCAN
=
100%
DS SCAN
=
0%
CW SCAN
=
100%
COW SCAN =
100%
O
~300% +4 = 75%
TOTAL COVERAGE ACHIEVED = 75%
DOWN STREAM (DS) SCAN LIMITED BY FLANGE 0