ML20141F414
| ML20141F414 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 09/30/1985 |
| From: | SCIENCE APPLICATIONS INTERNATIONAL CORP. (FORMERLY |
| To: | NRC |
| Shared Package | |
| ML20141F182 | List: |
| References | |
| CON-NRC-03-82-096, CON-NRC-3-82-96 SAIC-84-1653, NUDOCS 8602250502 | |
| Download: ML20141F414 (56) | |
Text
_ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ . _ . .
) 7 SAIC-84/1653
)
?
! TECHNICAL EVALUATION REPORT SECOND INTERVAL INSERVICE INSPECTION PROGRNi l
ZION NUCLEAR POWER STATION UNITS 1 AND 2
) Submitted to U. S. fbclear Regulatory Commission Contract Pb. 03-82-096 {
3 I
) Submitted by Science Applications International Corporation Idaho Falls, Idaho 83402
)
)
September 1985 8602250502 860211 gDR ADOCK 05000295 von
)
S CONTENTS I N TR OD UCT IO N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 l
I. C LASS 1 COM PO NE NTS . . . . . . . . . . . . . . . . . . . . . . . . 3 A. Re a c to r V es s el . . . . . . . . . . . . . . . . . . . . . . . . 3
- 1. Relief Request IWB tb. 2, Reactor Yessel,
) tbzzles, Inside Radius Sections, Category S-0, Item B3.100 ....................... 3 ;
- 2. Relief Request IWB tb. 5, Bolting and Studs, Reactor Vessel Closure Head, Category B-G-1, Items 86.20 and B6.30 .................. 6
- 8. Pressurizer ......................... 8
- 1. Relief Request IWB tb. 2, Pressurizer Nozzle Inside Radius Sections, Category B-D, Item B3.120 .... 8 O 2. Relief Request IWB tb. 3, Pressurizer Nozzle-to-Vessel Wel ds, Ca tegory B-D, Item B3.110, (Unit 2 only) ...................... 11 C. Heat Exchangers and Steam Generators . . . . . . . . . . . . . 13 O 1. Relief Request IWB Pb. 2, Steam Generator Nozzle Inside Radii, Category B-D, Item 83.140 . . . . . . 13
- 2. Relief Request IWB Pb. 4, Steam Generator Nozzle-to-Safe End Wel ds, Ca tegory B-F, o
Item B5.70 . . . . . . . . . . . . . . . . . . . . . . . . 15 l
D. Piping Pressure Boundary . . . . . . . . . . . . . . . . . . . 17
- 1. Relief Request IWB lb. 7, Circumferential Butt Welds in 15-Degree Reactor Coolant System Elbows, Ca te go ry B -J, Item B9.11 . . . . . . . . . . . . . . . . . 17
- 2. Relief Request IWB lb. 8, Lor.gitudinal Electroslag Welds and Cast-to-Cast Circumferential Welds, Category B-J, Items B9.11 and 89.12 ........... 19
- 3. Relief Request IWB lb. 9, Branch-to-Pipe Connection Wel ds, Ca tegory B-J, Item B9.31. . . . . . . . 22 E. Pump P res s u re Bo un da ry . . . . . . . . . . . . . . . . . . . . 24
- 1. Relief Request IWB tb. 5, Bol ts and Studs,
_ Reactor Coolant Pump Main Flange, Category B-G-1, Item B6.180 ... ........ 24
_i _
)
F. Valve Pressure Boundary ................... 26
- 1. Relief Request IWB tb.10, Class 1 Valves
) Greater Than 4-Inches, Internal Examinations,
- Category B41-2, Item 812.50 .... ..... 26
- 2. Relief Request IWB tb. 5, Bolts and Studs on Valve Bonnets, Category B-G-1, Item 86.2.10 . . . . . . . . 28
) II. CLASS 2 COMP 0NENTS . . . . . . . ..... 10 A. Pressure Vessels ............. 30
- 1. Relief Request IWC No.1, Class 2 Pressure Yessels with Wall Thicknesses 1/2-Inch or Less, Catagory C-A,
) Items C1.10, C1.20, and C1.30 ........ . 30
- 2. Relief Request IWC tb. 5, Regenerative Heat Exchanger Circumferential Welds, Category C-A, Items C1.10, t .20, and C1. 30 .............. 32
) 3. Relief Requests IWC No. 2 and IWC No. 3, All Class 2 Nozzle-to-Shell and Inside Radius Section Examinations , Category C-B, Items C2. 21 and C2. 22 .... 34
- 8. Pi ping Pressure Boundary . . . . . . . . . . . . . . . . . . . 37
- 1. Relief Request IWC No. 4, Branch Connections
}
l with Welded Reinforcing Saddles, Category C-F, Item C5.30 . . . . . . . . . . . . . . . . . . . . . . . . 37 C. Pumps ( No relief requests)
) D. Valves (?b relief requests)
III. CLASS 3 CCMP0NENTS (fb relief requests)
IV. PR ES S UR E TES TS . . . . . . . . . . . . . . . . . . . . . . . . . . 40
) A. General ........................... 40
- 1. !tidro Relief Request Pbs.1 and 2, Class 2 Piping tbt Isolable from Class 1 Piping ......... 40
- 2. FFydro Relief Request lbs.1 and 7, Pressure
) Tests Associated with the Reactor Coolant Pump S e a l A re a s . . . . . . . . . . . . . . . . . . . . . . . . 43
- 3. Hydro Relief Request Nos.1, 2, and 8, Class 1 and 2 Pipe Sections Pbt Testable with Present Confiqurations ............... 45
)
)
- 4. Hydro Relief Request %s. 3 and 6, Various
) Class 3 Piping Sections ....... 47
- 5. Hydro Relief Request Pb. 5, Steam Generators and Attached Class 2 and Class 3 Piping ........ 50
)
R EF ER ENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
)
)
)
)
)
) '
)
-f i t -
)
)
l TECHNICAL EVALUATION REPORT SECOND INTERVAL INSERVICE INSPECTION PROCRAM l
) Zion ibclear Power Station, Units 1 and 2 1
INTRODUCTION This report evaluates requests for relief from certain examination and 2 pressure test requirements of Section XI of the American Society of Mech-anical Engineers ( ASME) Boiler and Pressure Vessel Code
- by the licensee, Commonwealth Edison Company (CECO), of the Zion ibclear Power Station, Units 1 and 2. The relief requests cover the second 120-month inspection intervals starting Decenter 31, 1983, for Unit 1, and September 19, 1984, for Unit 2. The requests are based on the 1980 Edition of Section XI, with
) Addenda through Winter 1981, as specified in the applicable revision qf 10 CFR 50.55a. Inspection intervals and examinations are scheduledtl1 according to Inspection Program B (IWA-2420 and Tables IWB-2412-1 and IWC-2412-1 ).
The current revision to 10 CFR 50.55a requires that Inservice Inspection (ISI) programs be updated each 120 months to meet the require-ments of newer editions of Section XI. Speci fically, each program is to meet the requirements (to the extent practical) of the edition and addenda of the Code incorporated in the regulation by reference in paragraph (b) 12 months before the start of the current 120-month interval.
) The regulation recognizes that the requirements of the later editions and addenda of the Code might not be practical to implement at facilities because of limitations due to design, geometry, and materials of construc-tion of components and systems. Therefore, the regulation permits exceptions to impractical examination or testing requirements to be evalu-a ted. Relief from these requirements can be granted, provided the health
)
and safety of the public are not endangered, giving due consideration to the burden placed on the licensee if the requirements were imposed. This report only evaluates requests for relief dealing with inservice examina-tions of components and with system pressure tests relating to Zion's second ISI interval . Outstanding relief requests from the first ISI interval and the second interval inservice test (IST) program for pumps f and valves are being evaluated separately.
The current revision of the regulation also provides that ISI programs may meet the requirements of subsequent Code editions and addenda, incor-porated by reference in paragraph (b) and subject to thclear Regulatory
)
Comission (PRC) approval . Portions of such editions or addenda may be
- Hereinafter referred to asSection XI or Code.
)
i 1
I used provided that all related requirements of the respective editions or addenda are met. If applicable, these instances are addressed on a case-
) by-case basis in the body of this report.
l Finally,Section XI of the Code provides for certain components and systems to be exempted from its requirements. In some instances, these exemptions are not acceptable to the PRC or are only acceptable with res trictions . As appropriate, these instances are also discussed in this
) re port.
The ISI program for the second interval, includ ng relief requests, was submitted to the FRC by letter dated June 27,1983.{IJ On the same date, in accordance with 10 CFR 50.55a(g)(5), the licensee submitted requests not previously which submitted for was applicable relief to the firstfrom the 1974 inspection Edition, 2i Subsequently interval.(Symmer 1975 Code p
the ifcqnsee requested additional first-interval relief on August 23, 1983. t 3i The PRC pcted on both sets of first-interval relief requests on Decenter 28, 1984.44)
On May 11,1984,( 5) the PRC requested additional information to
) complete the review of the second-interval relief reques ts. The in-formation was furnishe as attachments to letters dated June 26, 1984,(6) and August 14,1984. t 7 These letters also contained a revision of one relief request submitted in Reference 1, four additional relief reauests, and three withdrawals.
) As a result of the above submittals, 20 second-interval relief requests
( IWB Nos. 2-5, 7-10, IWC Nos.1-5, and Hydro Request Nos.1-3 and 5-8) have been identified as requiring disposition. These requests are evaluated in the following sections of +.his report. Unless otherwise noted, all items in this report pertain to both Zion units.
)
)
)
)
2
{.
I. CLASS 1 COMPONENTS A. Reactor Vessel j 1. Relief Request IWB tb. 2, Reactor Vessel ibzzles, Inside Radius l Sections, Category B-D, Item B3.100
? Code Requirement l
l All inside radius sections in the reactor vessel shall be l volumetrically examined in accordance with Figures IWB-2500-7(a),
(b), (c), or (d) during each interval of operation. thzzles with
)
full penetration welds to vessel shell (or head) and integrally cast nozzles are included, but manways and handholes either welded to or integrally cast in the vessel are excluded. At least 25% but not more than 50% (credited) of the nozzles shall be examined by the end of the first inspection period and the remainder by the end of the third inspection period of each inspection interval. If examinations are conducted from inside the component and the nozzle k weld is examined by straight beam ultrasonic method from the nozzle bore, the remaining examinations required to be conducted from the shell may be performed at or near the end of each inspection in terval .
) Code Relief Request Relief is requested from the requirements of volumetrically examining 100% of all reactor vessel nozzle radii during each inspection interval.
)
Proposed Al ternative Examina tion All eight reactor vessel nozzles will be visually examined using remote techniques (.t or near the end of the interval when thE
)
lower internals are removed.
Licensee's Basis for Requesting Relief
) The nozzles in the reactor vessel contain inherent geometric constraints and clad inner surfaces whi::h limit the ability to perform meaningful volumetric or surface examinations in the radii areas.
)
3
)
The construction of Class I and II vessel nozzles is such that the inner radii of curvature are not symmetric to the outer radif of curvature; this lack of symmetry allows the ultrasonic beam to deviate from potential perpendicularity to a flaw preventing reli-
) able flaw detection. In addition, the as-cast outer surfaces of the nozzles add to the inability to gain meaningful results.
Performances of the alternative examinations will provide reasonable assurance of the structural integrity of these nozzles.
These alternatives will not affect the safety or integrity of the
) plant.
Evaluation
) Relief is warranted this interval but only for the Code-l required volume that cannot be achieved with current methods. The licensee should attempt to volumetrically examine the nozzle inner radius sections to the extent practical, when thq nozzle-to-vessel welds are examined. Also, the alternative visual examinations proposed by the licensee should be performed. The combination of
) these examinations will provide r .cessary assurance of tne structural integrity of the nozzle-to-vessel junction. It is consistent with the requirement imposed by the staff for the first in terval .
If the examinations are done manually with a single probe,
) acceptable ul trasonic testing resul ts could be difficult to ob ta in . There are, however, automatic ultrasonic testing systems being developed that use mul tiple probes and mul tiple frequencies.
These systems are equipped to process the large amounts of data necessary to detect flaws under the adverse conditions described by the i tcensee. Efforts should therefore be made to use suitable new ultrasonic testing equipment when it becomes commercially available.
Conclusions and Recommendations
) Based on the evaluation, it is concluded that for the subject inner radius sections, adherence to the Code requirements is impractical. It is further concluded that the examinations discussed will provide necessary assurance of structural reli-ability during this interval. Therefore, relief is recommended
[ for the Code volume that cannot be achieved with current methods
) provided that (a) volumetric examinations are performed to the maximum extent practical and (b) the subject nozzles are visually examined to the extent
) proposed by the licensee.
i 4
)
It is further recommended that the licensee make a reasonable t
I effort to use any appropriate automatic ultrasonic testing systems
) that become commercially available during the interval.
References
) References 1, 4, and 6.
i r
l i
l l
)
f I
l
)
l t
> 5
l
)
- 2. Relief Request IWB 2. 5, Bolting and Studs, Reactor Vessel Closure Head, Category B-G-1, Items B6.20 and 86.30
! Code Requirements l All reactor closure studs largar than 2 in, in diameter shall l be volemetrically examined in accordance with Figure IWB-2500-12 i during each inspection interval . Bolting may be examined (a) in i
place under tension, (b) when the connection is disassembled, or (c) when the bolting is removed. Examinations may be perforned at or near the end of the inspection interval. Additionally, the reactor vessel clnsure studs are to be surface examined when removed in accordance with Figure IWB-2500-12.
)
l Code Relief Request l
Relief is requested from volumetric examination of bolting and studs on the reactor vessel closure head.
Proposed Al ternative Examination Surface and visual (VT-1) examinations will be done at the time of component disassembly.
Licensee's Basis for Requesting Relief Due to the inherent geometry of threaded fasteners and signal interference from the threads, volumetric examinations do not pro-vide a significant benefit since a flaw would most likely originate at the surface (root areas).
Eval ua tion la trasonic testing of studs is an accepted means of examining for inservice flaws. However, some experts believe that surface examination of the studs when removed provides better results for the reasons provided by the licensee. The Code requires both ultrasonic and surface examination when the studs are removed.
The licensee has provided no compelling reason to eliminate a Code requirement (volumetric examination). Relief is not warranted under these circumstances.
6 i _____ _ ______ - - - - - _ _ _ _ - - - - - - - - - - - - - - - - -
Conclusions and Recommendations f Based on the evaluation, it is concluded that for the subject l studs, adherence to the Code requirements is not impractical and relief is not warranted. Therefore, it is recommended that the licensee should perform surface and ultrasonic examinations of the l studs when the reactor closure is disassembled.
)
Re ferences References 1 and 6.
)
l t
I
)
4 7
)
- 8. Pressurizer
- 1. Relief Request IWB Pb. 2, Pressurizer Nozzle Inside Radius Sections,
) Category B-D, Item B3.120 Code Requirement
> All inside radius sections in the pressurizer shall be volu-mtrically examined in accordance with Figures IWB-2500-7(a), (b),
(c), or (d) during each interval of operation. tbzzles with full ,
penetration welds to vessel shell (or head) and integrally cast nozzles are included, but manways and handholes either welded to or integrally cast in the vessel are excluded. At least 25% but not y more than 50% (credited) of the nozzles shall be examined by the l
end of the third inspection period of each inspection interval.
Code Relief Request
)
Relief is requested from the requirements of volumetrically examining 100% of all pressurizer nozzle radii during each inspection in terval .
k Proposed Alternative Examination All five upper head nozzles will be visually examined from the mancy using direct or remote techniques when disassembled at or near the end of the inspection interval.
?
l The lower head nozzle will be visually examined to the extent practical from the outside diameter just prior to a unit shutdown for refueling at the normal operating pressure and temperatures and during startJp after refueling at normal operating pressure and tempera ture.
Licensee's Basis for Requesting Relief The nozzles in the pressurizer contain inherent geometric
- constraints which limit the ability to perform meaningful volumtric or surface examinations in the radii areas. Also, the pressurizer lower head nozzle I.D. is visually restricted due to the sparger, thermal sleeve, and heater bank interferences.
)
4 8
)
The construction of Class I and II vessel nozzles is such that the inner radii of curvature are not symmetric to the outer radii of curvature; this lack of symmetry allows the ultrasonic beam to
) deviate from potential perpendicularity to a flaw preventing reliable flaw detection. In addition, the as-cast outer surfaces of the nozzles add to the inability to gain meaningful results.
Performances of the alternative examinations will provide reasonable assurance of the structural integrity of these nozzles.
) These alternatives will not affect the safety or integrity of the pl ant.
Eval uation
)
Relief is warranted this interval but only for the Code-required volume that cannot be achieved with current methods. The licensee should attempt to volumetrically examine the nozzle inner radius sections to the extent practical. Also, the al ternative visual examinations proposed by the licensee should be performed.
) The conbination of these examinations will provide necessary assur-ance of the structural integrity of these integrally cast nozzles for Unit 1. The examinations proposed for the Unit 2 pressurizer nozzle-to-vessel welds (see Section I.B.2) will provide added assurance for that junction in that unit.
). If the examinations are done manually with a single probe, acceptable ultrasoalc testing results could be difficult to obtain.
There are, however, automatic ultrasonic testing systems being developed that use mul tiple probes and mul tiple frequencies. These systems are equipped to process the large amounts of data necessary to detect flaws under the adverse conditions described by the
) 1icensee. Efforts should therefore be made to use suitable new ultrasonic testing equipment when it becomes commercially available.
) Conclusions and Recommendations Based on the evaluation, it is concluded that for the subject inner radius sections, adherence to the Code requirements is im-practical. It is further concluded that the examinations discussed will provide necessary assurance of structural reliability during
) this interval . Therefore, relief is recommended for the Code volume that cannot be achieved with current methods provided that (a ) the volumetric examinations are performed to the maximum extent practical and
)
) 9
)
(b ) the subject nozzles are visually examined to the extent proposed by the licensee.
)
It is further recommended that the licensee make a reasonable effort to use any appropriate automatic ul trasonic tes ting systems that become commercially available during the interval.
)
i l Re ferences .
References 1 and 6.
)
)
)
)
)
)
)
10
)
- 2. Relief Request IWB tb. 3, Pressurizer Nozzle-to-Vessel Welds, Category B-D, Item B3.110 (Unit 2 only)
Code Requirement
! All nozzle-to-vessel welds in the pressurizer shall be volu-j mtrically exanined in accordance with Figures IWB-2500-7(a), (b),
or (c) during the first interval of operation. At least 25% but not more than 507, (credited) of the nozzles shall be examined by the end of the first inspection period and the remainder by the end of the inspection period of each inspection interval. If examinations are cenducted from inside the component and the nozzle
) weld is exanined by straight beam ultrasonic method from the nozzle l bore, the remaining examinations required to be conducted from the shell may be performed at or near the end of each inspection in te rval .
) Code Relief Request Relief is requested from examining 100% of the required volumes of the Unit 2 pressurizer nozzle-to-vessel welds. Unit 1 pressurizer nozzles are integrally cast with the vessel heads.
) There are no Unit 1 welds requiring examination in this category.
Propose!1 Alternative Examination
) Saminations will be performed on the maximum volume of each weld that is reasonably achievable with current technology. Addi-tionnlly, a surface examination will be performed on the areas where volumtric exanination is prohibited.
) Licensee's Basis for Requesting Relief Zion Unit 2 nozzles are welded to the vessel heads. The con-figuration around the weld permits examination from the vessel head and on top of the weld. Exanination cannot be performed on the
) nozzle side due to configuration which prohibits the total volume from being examined as required by Code. The proposed alternative examinations will provide assurance of the continued structural integrity and will maintain an. adequate level of safety.
)
)
11
J Evaluation Relief is warranted this interval but only for the Code-
) required volume that cannot be achieved with current methods.
The alternative examinations (volumetric to the extent practical and surface on inaccessible areas) proposed by the licensee should be performed. These alternatives appear to be adequate for deter-mining the welds' structural integrity.
] If the examinations are done manually with a single probe, acceptable ultrasonic testing results could be difficult to ob tain . There are, however, automatic ultrasonic testing systems being developed that use mul tiple probes and mul tiple frequencies.
These systems are equipped to process the large amounts of data necessary to detect flaws under the adverse conditions described by 3 the licensee. Efforts should therefore be made to use suitable new ultrasonic testing equipment when it becomes conuercially available.
) Conclusions and Reconinendations Based on the evaluation, it is concluded that for the subject welds, adherence to the Code requirements is impractical. It is further concluded that the examinations discussed will provide the D necessary assurance of structural reliability during this inter-val . Therefore, relief is recommended for the Code volume that cannot be achieved with current nethods provided that (a) the volumetric examinations are performed to the maximum extent practical as proposed and
) (b) surface examinations are performed as proposed on those areas where Code-acceptable volumetric examination results cannot be obtained.
It is further recommended that the licensee make a reasonable
) effort to use any appropriata automatic ultrasonic testing systems that become commercially available during the interval.
3 References Reference 1.
)
) 12
e C. Heat Exchangers _and Steam Generators
- 1. Relief' Request IWB No. 2, Steam Generator Nozzle Inside' Radii, 3 Category B-D, Item B3.140 Code Requirement O
All inside radius sections in the steam generators shall be volumetrically examined in accordance with Figures IWB-2500-7(a),
(b), (c), or (d) during each interval of operation. Nozzles with full penetration welds to vessel shell (or head) and integrally cast nozzles are included, but manways and handholes either welded D to or integrally cast in the vessel are excluded. At least 25% but not more than 50% (credited) of the nozzles shall be examined by the end of the first inspection period and the remainder by the end.
of the third inspection period of each inspection interval.
D Code Relief Reauest Relief is requested from the requirements of volumetrically examining 100% of all steam generator nozzle radii during each inspection interval .
O Proposed Alternative Examination All eight nozzles will be visually examined from the manway l Q using manual or remote techniques when disassembled at or near the end of the ~ inspection interval.
l Licensee's Basis for Requesting Relief D
The. nozzles in the steam generators contain inherent geometric.
constraints which limit the ability to perform meaningful vclumetric or surface examinations in the radii areas.
The construction of Class I and II vessel nozzles is such that D'
the inner radii of curvature are not symmetric to the outer radii of curvature; this lack of symmetry allows the ultrasonic beam to 'devi-ate from potential perpendicularity to a flaw preventing reliable flaw detection. In addition, the as-cast outer surfaces of the nozzles add to the inability to gain ~ meaningful resul ts.
J 13
)
Performances of the alternative examinations' will provide reasonable assurance of the structural integrity of these nozzles.
These alternatives will not affect the safety or integrity of the
) pl ant.
Evaluation
) Relief is warranted this interval but only for the Code-required volume that cannot be achieved with current methods. The licensee should attempt to volumetrically examine the nozzle inner radius sections to the extent practical. Also, the alternative visual examinations proposed by the licensee should be performed.
The conbination of these examinations will provide necessary assur-
) ance of the structural integrity of these integrally cast nozzles.
If the examinations are done manually with a single probe, acceptable results could be difficult to obtain. There are, how-ever, automatic ul trasonic testing systems being developed that use
. multipl a probes and multiple frequencies. These systems are
) equipped to process the large amounts of data necessary to detect flaws under the adverse conditions described by the licensee.
Efforts should therefore be made to use suitable new ultrasonic testing equipment when it becomes commercially available.
)
Conclusions and Recommendations Based on the evaluation, it is concluded that for the subject inner radius sections, adherence to the Code requirements is im-practical . It is further concluded that the examinations discussed
) will provide necessary assurance of structural reliability during this interval . Therefore, relief is recommended for the Code volume that cannot be achieved with current methods provided that (a) volumetric examinations are performed to the maximum extent practical and
)
(b) the subject nozzles are visually examined to the extent proposed by the licensee.
It is further recommended that the licensee make a reasonable effort to use any appropriate automtic ultrasonic testing systems
) that become commercially available during the interval.
Re ferences
) References 1 and 6.
) 14
C)
- 2. Relief Request IWB k. 4, Steam Generator Nozzle-to-Safe End Welds, Category B-F, Item B5.70 iO Code Requirement Steam generator nozzle-to-safe end welds greater than or equal to 4-in. diameter are to be examined in accordance with Figure IWB-
- 2500-8 by volumetric and surface means each interval. Examinations d are required of each safe-end weld in each loop and connecting branches of the reactor coolant system. The examinations may not be deferred to the end of the interval. The examinations include dissimilar metal welds between combinations of (a) carbon or low alloy steels to high alloy steels, (b) carbon or low alloy steel to high nickel alloys, and (c) high alloy steel to high nickel alloys.
- O Code Relief Request n Relief is requested from examining 100% of the required volume
'u on the steam generator nozzle-to-safe end welds.
Proposed Alternative Examination O volumetric examinations to the extent practical and visual (VT-2) examinations will be performed, in addition to the Code-required surface exam' nation.
O Licensee's Basis for Requesting Relief Examination of the steam generator primary nozzle safe-end to pipe welds is limited to both by the nozzle geometry, surface con-dition, and the limited surface preparation on-the pipe side of the wel d. The surface on the pipe side of the weld, which is a c.tst O elbow, is machined for a distance of approximately 3 inches fro.n the edge of the weld. (D trasonic examination is limited to this distance from the edge of the weld. Examinations can be performed on the surface of the weld but are severely limited from the nozzle e side by the rough, or cast surface. ;
Due to geometric configuration and surface preparation of areas around these welds, it is impossible to obtain meaningful results for uitrasonic examinations on 100% of the Code-required volume. An estimated 80% of the required volume (90 to 100% of weld volume) can be inspected. The majority of the volume which g cannot be inspected consists of base metal of the tapered, machine prepared side. ,
?O 15
- m e m en- m- <
-p u
O The alternative examinations proposed will provide adequate assurance of the continued structural integrity and will maintain
. the level of safety at the_ plant.
O Evalua tion The licensee should attempt to volumetrically examine the subject areas to the extent practical. Relief is warranted this interval but only for the Code-required volume that cannot be O achieved with current methods. Also, the alternative visual (VT-2) examinations proposed by the licensee should be performed, in addition to the Code-required surface examination. The visual examination during pressure tests would provide initial evidence of seepage from a through-wall perforation. The cottination of these examinations appears to be adequate for determining the welds' lo structural integrity.
If the examinations are done manually with a single probe,
, acceptable ultrasonic testing results could be difficult to ob tain . There are, however, automatic ultrasonic testing systems being developed that use mul tiple probes and mul tiple frequencies.
,0 These systems are equipped to process the large amounts of data necessary to detect flaws under the adverse conditions described by the licensee. Efforts should therefore be made to use suitable new ultrasonic testing equipment when it becomes commercially available.
!O --
Conclusions and Recommendations Based on the referenced evaluation, it is concluded that for the subject welds, adherence to the Code requirements is imprac-
'o ti cal . It is further concluded that the examinations discussed will provide necessary assurance of structural reliability during this interval . Therefore, relief is recommended for the Code volume that cannot be achieved with current methods provided that (a) the volumetric examinations are performed to the maximum
.O extent practical, as proposed and (b) visual (VT-2) and the Code-required surface examina-tions are performd as proposed.
It is further recommended that the licensee make a reasonable
.O effort to use any appropriate automatic ultrasonic testing systems that become commercially available during the interval.
Re ferences
=O References 1 and 6.
o 16
O D. Piping Pressure Boundary l
iC) 1. Relief Request IWB No. 7, Circumferential Butt Welds in 15-Degree
! Reactor Coolant System Elbows,' Category B-J, Item B9.11 (Item B4.5 in 1974 S75)
!O:
Code Requirement-The licensee has optionally (as allowed by 10 CFR 50.55a(b) ,
(2)(ii)) chosen to determine the extent of examination of Class 1 lC) piping welds using the 1974 Edition, Summer 1975 Addenda. This Code requires that examination be performed on all the area of 25% :
of the circumferential joints (including the adjoining 1-ft I
- sections of longitudinal welds) each interval. A different 25% !
sample is required in successive intervals. The 1980 W81 Code requires that, for circunferential welds in pipe of nominal size "C) 4 in, and greater, surface plus volumetric examinations be performed in accordance with Figure IWB-2500-8.
i Code Relief Request
- C)
Relief is requested from volumetric or surface examination on four reactor coolant circunferential butt welds.
.C) Proposed Alternative Examination
. YT-2 visual examinations will be performed during all pressure tes ts.
- O Licensee's Basis for Requesting Relief The circumferential butt welds attach the pipe to 15-degree elbows in each of the reactor coolant cold legs. Each of these welds is completely enclosed within the biological shield wall and C) not accessible for the examinations as required by code. The pro-posed alternative VT-2 examinations will provide assurance of continued structural integrity and will maintain an adequate level of safety.
4 1
4 i
.O 17
O.
Evaluation o" The number of inaccessible welds is small in relation to the total nunber of welds in the reactor coolant system. Also, if it is assumed that the workmanship and quality assurance of the welding were adequate, then examining other welds in the reactor coolant system should reflect their overall material condition.
The Code being used requires that the licensee pick different welds to examine each interval . Therefore, relief will be needed for the
'O
~
subject welds, although the licensee should attempt to maintain the required 25% sample size this interval . for this system. Al so , the proposed visual examinations, which will provide initial evidence of seepage from a through-wall perforation, should be performed during the pressure tests in accordance with IWA-5000.
- O o
Conclusions and Recommendations Based on the above evaluation, it is concluded that for the welds discussed above, the Code requirements are impractical.
It 10 is further concluded that the alternative examination discussed above will provide necessary added assurance of structural reli-ability. Therefore, it is recommended that relief be granted from the examination of the identifled welds with the following provisions:
O (a) The Code-required 25% sample size should be mintained, if practical, for examining the other welds in the system.
(b) The proposed visual examinations should be performed when leakage and hydrostatic tests are conducted in accordance
- O with IWA-5000.
References O
Reference 1.
'o i
- O 10 18
J
- 2. Relief Request IWB b. 8, Longitudinal Electroslag Welds and Cast-to-Cast Circumferential Welds, Category B-J, Items B9.11 and B9.12 O (Item B4.5 in 1974 S75)
Code Requirement The ifcensee has optionally (as allowed by 10 CFR 50.55a(b)
V (2)(11)) chosen to determine the extent of examination of Class 1 piping welds using the 1974 Edition, Summer 1975 Addenda. This Code requires that examinations be performed on all the area of 25%
of the circumferential joints (including the adjoining 1-ft sections of longitudinal welds) each interval. A different 25%
'q sample is required in successive intervals. The 1980 W81 Code requires that for circumferential and longitudinal welds in pipe of nominal size 4 in. and greater, surface plus volumetric examinations be performed in accordance with Figure IWB-2500-8.
n" Code Relief Request Relief is requested from performing volumetric examination on longitudinal electroslag welds and circumferential welds that are ca s t-to -cas t.
O Proposed Alternative Examination VT-2 visual examinations will be performed during all pressure
,g tes ts .
Licensee's Basis for Requesting Relief O L ngitudinal welds in the main reactor coolant loop, 90-degree j elbows, were made by the electroslag weld process in joining the two cast halves in each of the eight elbows. Present ultrasonic '
methods will provide no meaningful results due to the highly at- f tenuative characteristics of the austenitic grain structure in i these areas. l
'3 Ultrasonic examination of circumferential welds between cast stainless steel materials does not produce reliable and meaningful resul ts . The material properties of cast stainless steel attenuate and scatter ultrasound to the degree that examinations are effectively impossible.
g g 19
O Radiography is an impractical technique to use and, if applied, is not expected to provide any meaningful increase in benefit beyond the alternative presented due to the high levels of
.O background radiation emitting from these areas.
The combination of both the Code-required surface and al ternative VT-2 examinations will provide assurance of continued structural integrity and will maintain an adequate level of safety.
- O Evalua tion The metallurgical characteristics of cast and electroslag welded stainless steel materials are such that ultrasonic signals
- O are greatly dispersed and attenuated in these media. Experience has shown that results vary greatly from plant-to-plant and weld-to-weld depending in part upon the structure of the base metal .
Consequently, ultrasonic testing (UT) is currently not a con-sistently practical method for volumetrically examining components of this construction. The Westinghouse Owners Group has advised
'O the utC of the starting of a research program based on initial success at Millstone 3 with the refracted L-wave method.
Radiographic testing, using a MINAC/Shrinkac X-ray system, should also be considered as an alternative. Historically, radio-graphic testing is not normally considered as a method for reactor
- O piping ISI. Under norm 1 ISI conditions reactor piping, valves, and pumps remain filled with water, and it is frequently imprac-tical to drain all or any part of a system. Coherent or Rayleigh scattering in water from regular X-ray beams or radiography sources usually redJces or effectively eliminates discontinuity imging except for large, gross discontinuities. Also, thick sectioned
- O piping and valve and pump bodies require extended radiographic exposure time to acquire optimum film densities.
~; The use of MINAC/Shrinkac eliminates the problem of Coherent or Rayleigh scattering. Frequently, 2-2T radiographic quality is e-walled radiography in water-filled
.O possible pi when pes . L 9,10) J. shooting A. Jones tdoppi reports exposure times for weld thick-nesses that vary from 7.5 to 12 inches of from 10 to 110 minutes, depending on weld thickp sg gnd distance. The relatively small size of a Shrinkac headt e'Oi makes it possible to position the i head in all but the most difficul t positions. Electric Power Research Institute (EPRI) reports (9) that MINAC/Shrinkac radio-
- O graphy has been accomplished in the presence of high (1 to 2 R/h) radiation backgrounds.
! Because ultrasonic testing of the subject welds is likely not to be practical and because the applicability of MINAC/Shrinkac examinations to them is uncertain, relief from the Code-required lO
- volumetric exaninations would be appropriate. Because of the great I variability of the current ultrasonic methods, the licensee should i
r 20 (O
l
!O attempt UT on a 25% sample of these welds to demonstrate whether these methods are indeed impractical for his units. The licensee
- O should also actively pursue using MINAC/Shrinkac wherever practical to examine the subject components. The proposed visual (which will l
provide initial evidence of seepage from a through-wall perforation) and Code-required surface examinations will also add a measure of l
knowledge on the integrity of these components.
l O ,
Conclusions and Recommendations Based on the above evaluation, it is concluded that for the l welds discussed above, the Code requirements are likely to be
- impractical at this time. It is further concluded that the
'O alternative examinations discussed in the evaluation above will provide necessary added assurance of structural reliability.
Therefore, relief is racommended from the volumetric examination of the identified welds with the following provisions:
3 (a) The licensee should demonstrate on a 25% sample of the O subject welds whether ultrasonic testing by current methods is indeed impractical for his units.
(b) The Code-required surface and alternative visual (VT-2) examinations during pressure tests should be performed as proposed.
O It is further recommended that the licensee make a reasonable effort to examine the subject welds by MINAC/Shrinkac.
O References References 1, 8, 9, and 10.
l lO l
- O O
O 21
LO i
- 3. Relief Request IWB No. 9, Branch-to-Pipe Connection Welds, Category B-J, Item B9.31 (Items 84.6 and B4.7 in 1974 S75)
O Code Requirement As allwed by 10 CFR 50.55a(b)(2)(ii), the licensee has i elected to use the 1974 Edition of the Code, Summer 1975 Addenda to iO determine the extent of piping examinations under Category B-J.
The examinations performed during each inspection interval shall cover all the area of 25% of the pipe branch connection joints.
This Code requires that a different 25% sample be examined in successive intervals. The 1980 W81 Code requires that for welds in branch connections greater than 4 in., surface plus volumetric on examinations be performed in accordance with Figures IWB-2500-9,
-10, and -11.
Code Relief Request O
Relief is requested from performing volumetric examinations on branch pipe connection welds.
O Proposed Al ternative Examination YT-2 visual examinations will be performed during all pressure j tes ts.
O Licensee's Basis for Requesting Relief Weld configuration and materials of construction preclude any meaningful volumetric examinations presently in use. The conbined Code-required surface and alternative VT-2 examinations will pro-O vide assurance of continued structural integrity and will maintain an adequate level of safety.
, Evalua tion O It is expected that means will become available before the end of the interval to better examine welds with geometric constraints (see Section I. A.1 ). Currently MINAC/Shrinkac has been used (see Section I.D.2) to examine some welds with material constraints to -
UT examination. Hence, it may be possible to volumetrically b examine a significant percentage of branch connection welds. But h
because ultrasonic testing of the subject welds is not practical and because the applicability of MINAC/Shrinkac examinations to O
22 l
O them is uncertain, relief from the Code-required volumetric examinations would be appropriate. The licensee should, however, actively pursue using MINAC/Shrinkac wherever practical to examine the subject components. The licensee should also keep informed of
.O the new automated ultrasonic systems on the market and make a reasonable effort to use appropriate systems as they become commercially available. The proposed visual (which will provide initial evidence of seepage from a through-wall perforation) and Code-required surface examinations will also add a measure of kn wiedge n the integrity f these components.
O Conclusions and Recommendations Based on the evaluations referenced, it is concluded that for O the subject welds, adherence to the Code requirements is impracti-cal . It is further concluded that the examinations discussed will provide necessary assurance of structural reliability during this in terval . Therefore, relief is recommended as requested provided the licensee O (a) volumetrically examines the subject welds to the maximum extent practical and (b) performs the Code surface and proposed visual exami-
- nations according to the schedule of Table IWB-2412-1.
O It is further reco.nmended that the ifcensee actively pursue the use of any appropriate automatic ultrasonic testing or MINAC/Shrinkac systems that become commercially available during the interval to perform the required volumetric examinations.
O References M
Reference 1.
O (t O
O 23 g
- O E. Pump Pressure Boundary
- 1. Relief Request IWB 2. 5, Bolts and Studs, Reactor Coolant Pump Main Flange , Category B-G-1, Item B6.180
- O l
Code Requirements l
All bolts and studs larger than 2 in. in diameter in pumps ,
O shall be volumetrically examined in accordance with Figure IWB-2500-12 during each inspection interval . Bolting may be examined (a) in place under tension, (b) when the connection is disassembled, or (c) when the bolting is removed. Examinations may be performed at or near the end of the inspection interval. Exami -
nations are limited to bolts and studs on pumps selected for O examination under Examination Category B-L-1, as applicable.
Code Relief Request O Relief is requested from volumetric examination of bolting and -
studs on the reactor coolant pump main flange.
Proposed Alternative Examination Surface and visual (VT-1) examinations will be done at the time of component disassembly.
O Licensee's Basis for Requesting Relief Due to the inherent geometry of threaded fasteners and signal interference from the threads, volumetric examinations do not pro-vide a significant benefit since a flaw would most likely originate at the surface (root areas).
O Evalua tion Ultrasonic testing of bolts is an accepted means of examining O for inservice flaws. However, some experts believe that surface examination of the bolts when removed provides better results for the reasons provided by the licensee. The licensee has also proposed to perform visual (VT-1) examinations at disassembly, i which is required by Code Category B-L-2, Pump Casings, and to i which he has committed for this interval. Thus, the ifcensee's lO proposal should be accepted as an adequate substitute for the Code '
l requirement.
lO
! 24
I
!O l Conclusions and Recommendations Based on the evaluation, it is concluded that for the subject lO bolts, adherence to the Code requirements is impractical. It is .
further concluded that the alternative examinations discussed will provide the necessary assurance of structural reliability during this interval . Therefore, the following is recommended:
jo (1 ) Relief should be granted from performing ultrasonic l
examinations of the subject bolts.
i I ( 2) The licensee should perform surface and visual (YT-1) examinations of the bolts whenever a pump is disassembled per requirements of Code Category B-L-2.
O References O References 1 and 6.
O O
l 0
O l
O 25
- O 1
J F. Valve Pressure Boundary 0 1. Relief Request IWB %.10, Class 1 Valves Greater than 4-Inches, Internal Examinations, Category B-M-2, Item B12.50 Code Requirement g
The internal surfaces of at least one valve in each group of valves with the same construction design (e.g., globe, gate, or check valve) and manufacturing method that perform similar functions in the system (e.g., containment isolation and system verpressure protection) shall be visually examined (VT-3) during O each inspection interval. Examination my be performed on the same valve selected for volumetric examination of welds. The exami-nations may be performed at or near the end of the inspection in terval .
Code Relief Request Relief is requested to defer the required internal examina-tions on valve bodies which exceed 4-inch noninal pipe size until maintenance is required.
O Proposed Al ternative Examination Those valves disassembled for maintenance will be Code-O examined.
Licencee's Basis for Requesting Relief n"
The Code requirement to disassemble one valve from each design group for the purpose of visual examinations has a small potential for identification of service-induced flaws or degradation. The industrial performance of these valves has proven their excellent ability to resist service degradation or flawing. The combination of low potential for flaw detection and the large impact on expen-o' ditures of manpower does not substantially increase component reliability and is considered impractical. Also, the substantial expenditures of man-rem without increasing component integrity is
. undesirable due to ALARA concerns. As an alternative, these examinations will be ptrformd when disassembly is required for maintenance purposes but not greater than once per each inspection g in terval . Delay of these examinations until maintenance is per-formed will not affect the function or integrity of these componen ts.
O 26
~,
O-Eval uation
- g The Code-required visual examination specified is- to determine i whether unanticipated severe degradation of the body is occurring due to phenomena such as erosion or corrosion. However, the dis-assenbly of large valves to the degree necessary to inspect the internal pressure-retaining surfaces (bodies) is a major effort in terms of exposure of personnel. To do this disassembly solely to perform a visual examination of the internal bo# is impractical.
- O The licensee's proposed alternative to examine valves disassembled for maintenance is adequate to determine the overall condition of Class 1 valves.
Conclusions and Recommendations
' Based upo'n the above evaluation, it is concluded that for the valves discussed above, the Code requirements are impractical. It
- is further concluded that the alternative proposed examination IO discussed above will provide necessary added assurance of structural reliability. Therefore, the following are recommended:
i (a) Relief should be granted from the Code requirement to j visually examine the internal surfaces of Class 1 valves.
- (b) Any valves disassembled for maintenance should be Code-
)o examined as proposed, l
- o Reference Reference 1.
]
lo
!O T
!O 1
27
- O
~_
- 2. Relief Request IWB ib. 5, Bolts and Studs on Valve Bonnets, Category B-G-1, Item B6.210 0
Code Requirement All bolts and studs larger than 2 in. in diameter in valves shall be volumetrically examined in accordance with Figure q IWB-2500-12 during each inspection interval. Bolting may be
~
examined (a) in place under tension, (b) when the connection is disassembled, or (c) when the bolting is removed. uaminations nuy be performd at or near the end of the inspection interval.
Examinations are limited to bolts and studs on valves selected for examination under Examination Category B-M-1, as applicable.
10 Code Relief Request Relief is requestod from volumetric examination of bolting andjf lC studs on the valve bonnets. 47 l
l Proposed Al tornative Examination lO Surface and visual (VT-1) examinations will be done at the l time of component disassenbly.
Licensee's Basis for Requesting Relief iO Due to the inherent geoinetry of threaded fasteners and signal interference from the threads, volumetric examinations do not pro-l vide a significant benefit since a flaw would most likely originate at the surface (root areas).
O Eval ua tion The licensee has asked to perform surface and visual examina-tions when the valves are disassembled. The licensee has also asked LO for relief to examine valves when disassembled for maintenance (see i I. F.1 ). So, in effect, the examinations on b01 ts and studs in some l valves might never be performed. Clearly, the intent of the Code is that the examinations be performed. Thus, even though the volu-i metric examinations may not be as good as a surface examination when the valves are disassembled, they should be performed at the re-O quired frequency on Category B41-1 valves that are not disassembled
[
LO 20
O l for maintenance.* The licensee's proposal to surface and visually 4 i examine these bol ts and studs whenever a valve is disassembled for l maintenance should be accepted.
lO l
Conclusions and Recominendations Based on the above evaluation, it is concluded that for the subject bol ts and studs, the Code requirements are not totally im-O practical; only partial relief is recommended. The licensee should be permitted to substitute the surface and visual examinations for volumetric whenever a valve is disassembled for maintenance provided the volumetric examinations are performed at the other times required by the Code.
O
'i Re ferences O References 1, 2, and 6.
O O
i O
I i
'O
- Under similar circumstances for pump casings in the first interval, the licensee committed to examine RCP bolting in-place using the ultrasonic back reflection method.
O l
l 29 lO -
i
!O' i II. CLASS 2 COMPONENTS A. Pressure Vessels
- 1. Relief Request IWC No.1, Class 2 Pressure Vessels with Wall Thicknesses 1/2-Inch or Less, Category C-A, Items C1.10, C1.20, l
and C1.30 .
lO Code Requirements Essentially 100'. of shell circumferential welds at gross structural discontinuities, the head-to-shell circumferential C welds, and shell-to-tube sheet welds shall be volumetrically examined in accordance with Figure IWC-2520-1 during each inspection interval . For multiple vessels with similar design, size, and service (such as steam generators and heat exchangers),
the required examinations may be limited to one vessel or distri-g buted among the vessels.
Code Relief Request Relief is requested from the above Code volumetric examination requirements for the following pressure vessels:
O I Vessel Shell Thickness (inches) i .
l Seal Water Return Filter 0.165 to 0.185 l Seal Water Heat Exchanger 0.165 to 0.185
! Reactor Coolant Filter 0.165 to 0.185
!O volume Control Tank 0.218 to 0.250 Proposed Alternative Examinations O The above vessels will be subjected to surface and visual I (VT-1) exaninations in Ifeu of the required volumetric examinations, j g Licensee's Basis for Requesting Relief 1
l Ultrasonic examinations to the extent practical in the past interval have shown that the welds and base materials of the above vessels are much too thin to produce meaningful examinations.
Also, when geometry, design, and materials of construction are
'O taken int acc unt, the reliability of the UT examinations is reduced even further. The conbination of the proposed surface l
30 O
g and visual examinations will provide meaningful results and assure ccntinued structural integrity. The alternative exaninations as
.g proposed will maintain the required level of safety at the plant.
Evalua tion g The Code considers that, for piping and nozzle-to-vessel welds, ultrasonic methods of volumetric testing require a material to be greater than 1/2-in thick for proper return of signals. If these welds aro 1/2-in. thic'< or less, they are required only to be examined by surface methods. Hence, it would be appropriate to apply this criterion equally to all ultrasonic testing examinations g of material 1/2-in. thick or less. The ifcensee's proposed surface and visual exaninations should provide adequate information on the intagrity of the subject vessels.
J
- O Conclusions and Recommendations Based on the above evaluation, it is concluded that for the examinations discussed above, the Code requirements are impractical.
It is further concluded that the alternative examinations discussed above will provide necessary added assurance of structural reli-LO abil ity. Therefore, the following are recommended:
! (a) Relief should be granted from the required volunatric examinations of the subject vessels.
1 (b) As a condition of reifef, the proposed surface and YT-1 O visu11 examinations should be performed in lieu of the
- j. required volumetric examinations. '
l 1
- g Re ferences 1 Reference 1.
,0
'O 3I O
lO
- 2. Relief Request NC No. 5, Regenerative Heat Exchanger Circumferen-tial Welds , Category C-A, Items C1.10, C1.20, and C1.30
- O Code Requirement Essentially 100% of shell circumferential welds at gross structural discontinutties, the head-to-shell circumferential welds, and shell-to-tube sheet welds shall be volumetrically _
10 examined in accordance with Figure NC-2520-1 during each inspection interval . For multiple vessels with similar design, size, and service (such as steam generators and heat exchangers),
! the required examinations may be limited to one vessel or distri-buted among the vessels. >
0 Code Relief Request Reifef is requested from the volumetric examination of the O circumferential welds in the regenerative heat exchanger.
Proposed Alternative Examination O vi-1 and surface examinations will alternatively be performed on this component.
Licensee's Basis for Requesting Relief O
The regenerative heat exchanger is constructed of cast stain-less material. Ultrasonic examination of cast stainless steel material does not produce reliable and meaningful results. The material properties of cast stainless steel attenuate and scatter ultrasound to the degree that some examinations are effectively O impossible. The proposed alternative examinations will provide adequate assurance that the structural integrity and safety will be maintained during this interval.
O Evalua tion The metallurgical characteristics of cast stainless steel materials are such that ultrasonic signals are greatly dispersed and attenuated in these media. Consequently, ultrasonic testing is not a practical method for volumetrically examining components O of this ennstruction. Radiography is traditionally used to examine these components during fabrication. However, inservice radiography O 32 l
lC too, has limitations because of inaccessibility of component' interfors and high background radiation.
!O The licensee's proposed surface and visual examinations should provide adequate information on the integrity of the regenerative heat exchanger.
lO Conclusions and Recommendations Based on the above evaluation, it is concluded that for the examinations discussed above, the Code requirements are impractical .
It is further concluded that the alternative examinations discussed O above will provide necessary added assurance of structural reli-abii t ty. Therefore, the following are recommended:
(a) Relief should be granted from the required volumetric examinations of the regenerative heat exchanger.
O (b) As a condition of relief, the proposed surface and VT-1 visual examinations should be performed in lieu of the required volumetric examinations.
1 0 t Re ferences l
l Reference 1.
P
!O l
O-f O
1 f
<O 33
- 3. Relief Requests IWC No. 2 and IWC No. 3, All Class 2 Nozzle-to-Shell and Inside Radius Section Examinations, Category C-B, Items C2.21 and C2.22 0 '
Code Requirement The nozzle-to-shell (or head) welds of all nozzles in vessels over 1/2 in. in nominal thickness at terminal ends of piping runs n shall be surface and volumetrically examined in accordance with Y
Figure IWC-2520-4(a) or (b) during each inspection interval.
Terminal ends include nozzles welded to or integrally cast in vessels that connect to piping runs (manways and handholes are excl uded). Only those piping runs selected for examination under Examination Category C-F are included. In addition, the inside n radius sections of these nozzles are to be volumetrically examined each interval in accordance with Figure IWC-2500-4(a) or (b).
Code Relief Request O
IWC No. 2: Relief is requested from examining 100% of the required volume on all Class II nozzle-to-shell welds.
l IWC tb. 3: Relief is requested from the requirements of volumetrically examining 100% of all nozzle radif subject to Item lO C2.22 during the inspection interval.
l l
Proposed Alternative Examinations
.g Pbzzle-to-Shell Welds: Volumetric examinations will be l performed on the maximum volume reasonably achievable with current l technology. The Codo-required surface examinations will also be done.
thzzle Inside Radif: VT-1 examinations will be performd to lq
~
the extent practical when they are disassembled. Main steam and feedwater nozzles will receive Vl'-2 examination during pressure tests only due to inaccessibility.
O Licensee's Basis for Requesting Relief IWC 4). 2: Limitations exist at these type welds where geo-metry and sometimes surface conditions preclude ultrasonic coupling or access for the required scan length to accomplish the full vol ume. The combination of both the limited ultrasonics proposed lg and the Code surface examinations will provide an assured means of flaw detection and will militain an adequate level of safety.
O 34
O IWC No. 3: All nozzle radii to be examined per Iten C2.22 -
contain inherent geometric and construction constraints which limit the ability to perform meaningful volumtric examinations.
n The alternative VT-1 examinations are proposed to be performed upon disassembly for other reasons rather than according to the re-quired frequency. This is because the visual examinations have a small potential for identification of service-induced flaws or degradation . The industrial performance of these components has
'n
~
proven their excellent ability to resist service degradation or fl awing. The inappropriate balance of potential flaw detection and the large impact on expenditures of manpower without substantially increasing component reliability is considered impractical. Al so, the substantial expenditures of man-rem without increasing compon-ent integrity is undesirable due to ALARA concerns.
in
[ Delay of these examinations until maintenance is performd as proposed will provide assurance of the continued structural l
integrity and mintain an adequate level of safety.
I O
Eval ua tion The licensee should attempt to volumetrically examine the subject areas to the extent practical. Relief is warranted this l interval but only for the Code-required volume that cannot be lO achieved with current mthods. Also, the Code-required surface and alternative visual examinations proposed by the ifcensee should be performed. The combination of these exaninations appears to be adequate for determining structural integrity of welds and nozzles.
- O If the examinations are done manually with a single probe, l acceptable ultrasonic testing results could be difficult to l ob tain. There are, however, automatic ultrasonic testing systems being developed that use multiple probes and multiple frequencies.
These systems are equipped to process the large amounts of data necessary to detect flaws under the adverse conditions described by lC the licensee. Efforts should therefore be made to use suitable new l ultrasonic testing equipnent when it becomes commercially available.
1 Conclusions and Recommenditions lO l
Based on the referenced evaluation, it is concluded that for I the subject welds and inside radfi, adherence to the Code require-
! ments is impractical . It is further concluded that the examina-
- tions discussed will provide necessary assurance of structural reliability during this interval . Therefore, relief is recommended lC for the Code volumes that cannot be achieved with current mthods I provided l
0 35
O (a) the volumetric examinations are performed to the maximum extent practical and O' (b) the proposed alternative visual and Code-required surface examinations are performed on the subject areas.
It is further recommended that the licensee make a reasonable effort to use any appropriate automatic ultrasonic testing systems o that become commercially available during the interval.
O Re ferences References 1 and 6.
O O
O O
O O
O 36
B. Piping Pressure Boundary
- 1. Relief Request IWC No. 4, Branch Connections with Welded
'O Reinforcing Saddles, Category C-F, Item C5.30 Code Requirement iO The surfaces of 100% of each circumferential weld in pipe branch connections shall be examined in accordance with Figure IWC-2520-9 to -13 inclusive during each inspection interval. The welds selected for examination s:1a11 include
'O a. all welds at locations where the stresses under the loadings resulting from Normal and Upset plant conditions as calculated by the sum of Equations 9 and 10 in NC-3652 exceed the speci-fied value; l
1 l b. all welds at terminal ends (see (e) below) of piping or
- O branch runs;
- c. all dissimilar metal welds; I
- d. additional welds, at structural discontinuities (see (f)
! below) such that the total nunber of welds selected for lO examination includes the following percentages of circum-l ferential piping welds;
! 2. none of the welds in residual heat removal and emergency core cooling systems, O 3. 10% of the main steam system welds 8 in. nominal pipe
- . size and smaller,
- 4. 25% of the welds in all other systems.
l
- e. terminal ends are the extremities of piping runs that connect O to structures, components (such as, vessels, pumps, and valves) or pipe anchors, each of which act as rigid re-straints or provide at least two degrees of restraint to piping thermal expansion.
- f. structural discontinuities include pipe weld joints to vessel O nozzles, valve bodies, pump casings, pipe fittings (such as, ,
elbows, tees, reducers, and flanges conforming to ANSI l Standard B16.9) and nine branch connections and fittings; O
l l
!O '
37 i
O For welds in carbon or low alloy steels, only those welds showing reportable preservice transverse indications need to be examined for transverse reflectors.
lO In addition, longitudinal welds in pipe branch connections shall be surface examined in accordance with Figure IWC-2520-12 and -13 (2.5 t at the intersecting circumferential weld) during each inspec-tion interval.
- O l Code Relief Request Relief is requested from the requirements of surface exami-nation on branch connection piping with welded saddle plates.
Proposed Alternative Examination f The design of each connection includes telltale holes to detect 10 evidence of leakage during syste.n pressure tests. As an alternative, VT-2 examinations will be performed during all pres-sure tests as a substitute for the required surface examinations.
l l
0 Licensee's Basis for Requesting Relief The design is a reinforcement saddle plate positioned directly over the pressure boundary weld and fillet welded in place. The geometry of this plate completely encases the main weld and precludes any meaningful surface examination.
The alternative visual examination proposed will provide l
l assurance of continued structural integrity and maintain an adequate level of safety at the station.
'O Eval ua tion The reinforcing saddles covering these branch connection welds prevent the performance of the Code-required surface examinations. ,
For nozzles, the Code recognizes that the reinforced design exists O and has in those cases spect fied that the saddle-to-pipe welds, rather than the pressure-retaining welds, be surface examined. It I would be appropriate, therefore, to extend this philosophy to similar designs in kranch connections.
,0 O 38
\
~O Hence, a reasonable alternative program to that required by the Code would be to surface examine all applicable saddle-to-pipe
'g fillet welds and do the proposed visual VT-2 examination during pressure tests, which would provide initial evidence of seepage from a through-wall perforation.
- g Conclusions and Recommendations Based upon the above evaluation, it is concluded that for the welds discussed above, the Code requirements are impractical. It is further concluded that the alternative examinations discussed in the evaluation above will provide necessary added assurance of
- O structural rel fability. Therefore, the following are recommended
- ,
(a) Relief should be granted from the surface examination requirements for the subject branch connection welds.
(b) Each saddle-to-pipe fillet weld should be surface lO examined at the Code-required frequency.
(c) The joints should be visually examined as preposed.
r
'O References Reference 1.
- O
!O l C. Purnps No relief requests.
- O D. valves
- lb relief requests.
l lO 2
0 39
- O
~
III. CLASS 3 COMP 0NENTS No Relief Requests.
C)
IV. PRESSURE TESTS A. General
]() 1. Rydro Relief Request Nos.1 and 2, Class 2 Piping Not Isolable from Class 1 Piping Code Requirement O
- IWB-5222(a )
- The system hydrostatic test may be conducted at any test pressure specified in Table IWB-5220-1 corresponding to die selected test temperature, provided the requirements of IWB-5230 are met for all ferritic steel components within the boundary of the system (or portion of system) subject to the test pressure (see
- C) IWA-5245) .
IWC-5222( a ): The system hydrostatic test pressure shall be at least 1.10 times the system pressure Psv for systems with design temperature of 2000F (930C) or less, and at least 1.25 times the system pressur 'sv for systems with design temperature above 2000F
- C) (9300). The system pressure Psy shall be the lowest pressure setting among the number of safety or reifef valves provided for overpressure protection within the boundary of the system to be tes ted. For systems (or portions of systems) not provided with safety or relief valves, the system design pressure Pd shall be substituted for Psy.
- C)
Code Relief Request Relief requested from the Code hydrostatic tasts of those Class (3 2 lines not isolable from Class 1 piping as follows:
Hydro Relief No. Attat.* Pipe Section Class 1 2-1 A0V-VC 8169 to VC 8352 8 2 ,
!C) 1 VC 8393 to VC 8392 2 2 2-6 A0V-VC 8381 to VC HCY 123 2 2 2-7 RCLCV-459 to ADV-VC 8149 A, B, C 2 1 4-1 MOV-RH 8703 to RH 8949 A, B 2 i
- O
- Refers to attachments of P& ids to the ifcensee's ISI program, Reference 1.
1 40
O Hydro Relief No. Attmt.* Pipe Section Class 1 5-2 MOV-SI 8802 to SI 9001 A,B 2 ^
' MOV-SI 8802 to SI 9001C,0 2 5-3 MOV-SI 9011B to SI 8949C,0 2
.o 1 1 5-4 MOV-SI 9001 A to RH 8949A,B 2 1 6-1 MOV-SI 8808C to SI 8948C 2 MOV-SI 8808B to SI 8948B 2 MOV-SI 88080 to SI 89480 2 MOV-SI 8808A to SI 8948A 2 6-2 MOV-SI 8809A to SI 9001 A,8 2
- o 1 1 6-3 MOV-SI 8809B to SI 9001C,0 2 10 Proposed Alternative Examination Visual examinations will be performd for evidence of leakage at normal operating pressures.
lO Licensee's Basis for Requesting Relief The above listed lines are portions of piping that are not isolable from the reactor coolant system if Class 2 specified hydrostatic pressure is applied, because the hydrostatic pressure
,0 required for this Class 2 system is above the reactor coolant system hydrostatic pressure. Therefore, these portions cannot be hydrostatically tested to the Class 2 pressure, but can be hydro-statically tested to a Class 1 hydrostatic pressure. However, reactor coolant hydrostatic pressure is only 45 psig above normal operation (1.02 Po = 2280). Therefore, it is requested that the
- O lines be examined at normal operating pressure (2235 psig).
Evaluation
'O The lines listed above are not isolable from the Class 1 reactor coolant system and therefore cannot be pressurized to Class 2 hydrostatic pressure. The ifcensee states that Class 1 hydrostatic pressure can be applied but commits only to examining ,
the lines at normal operating pressure. The magnitude of the I Class 1 test pressure is not relevant, and ' relief has not been
- O. - asked from performing a Class 1 hydrostatic test. Therefore, a i more appropriate alternative would be to perform the subject examinations during a Class 1 hydrostatic test. j i
l O'
- Refers to attachments of P& ids to the licensee's ISI program, l Reference 1. ;
I k
41
!O
., ?. . _ . _ _ _ _ _ _ -- .
-O Conclusions and Recommendations Based on the above evaluation, it is concluded that for the
.O examinations discussed above, the Code requirements are impractical .
It is further concluded that the alternative examination discussed in the evaluation will provide necessary added assurance of struc- '
tural reliability. Therefore, the following are recommended:
(a) Relief should be granted from the Class 2 hydrostatic
'O test requirements of the Code for the subject lines.
(b) The subject piping sections should alternatively be hydrostatically tested along with the reactor coolant system during Class 1 sys t+1 tes ting.
O References References 1 and 7.
- O
- 1 1 l
!O <
1
-O 4
O
!O
-O 42
- O L
- , .,,p , , , , , . . , _ , , ,e m ,m__ , _ , ,, .,, y ,, , , , , ._ ,,, _ __
'O
- 2. Hydro Relief Request Nos.1 and 7, Pressure Tests Associated With the Reactor Coolant Pump Seal Areas O
Code Requirement IWC-5222(a) and IWD-5223(a): The system hydrostatic test pressure shall be at least 1.10 times the system pressure Psv for O systems with design temperature of 2000F (930C) or less, and at least 1.25 times the system pressure Psv for systems with design temperature above 2000F (930C). The system pressure Psv shall be the lowest pressure setting among the number of safety or relief valves provided for overpressure protection within the boundary of the system to be tested. For systems (or portions of systems) not O provided with safety or relief valves, the system design pressure Pd shall be substituted for Psv-g Code Relief Request Relief requested from the Code-required hydrostatic tests of the following Class 2 and 3 system areas:
Hydro Relief %. Attmt.* Pipe Section Class O 1 2-2 RCP ' A' Seals 2 1 2-3 RCP 'B' Seals 2 1 2-4 RCP ' C' Seal s 2 1 2-5 RCP 'D' Seals 2 7 13-1 CC 9495A to RCP ' A' 3 7 13-2 CC 9495B to RCP 'B' 3 O 7 13-3 CC 9495C to RCP ' C' 3 7 13-4 CC 9495D to RCP 'D' 3 O Proposed Alternative Examination The lines leading to the reactor coolant pump seals will be blanked off and tested as required.. The seals themselves will not be tested. The component cooling lines to the thermal barriers will be tested to 187.5 psi along with the rest of the component ,
O cooling lines. l
- Refers to attachments of P& ids to the licensee's ISI program, O Reference 1.
l I
O 43 1
2C)~
Licensee's Basis for Requesting Relief Pressurizing the reactor coolant pump seals to Class 2 hydro L
~C) pressure during cold shutdown could misalign and damage. the seals.
Therefore, it is the station's position, with manufacturer's concurrence, not to pressurize the seals during Class 2 testing.
The design pressure of the component cooling system lines leading to the reactor coolant pump thermal barriers requires ethat
' () . they be hydrostatically tested to about 3000 psig. However, the maximum differential pressure allowed across the diermal barriers is 200 psi. The corresponding reactor coolant system pressure of about 2800 psig is much greater than Class 1 hydro pressure and, therefore, not attainable.- It would also require component cooling .
to be operational. Hence, the subject conponent cooling liaes lc) cannot be Code examined.
Evalua tion
- C) Performing the subject hydrostatic tests to Code requirements
- would likely result in danage to the reactor coolant pumps. There-
. fore, the reactor coolant pump seals and subject component cooling lines should not be Code tested. The Code required visual exami-nations at normal operating pressures (IWC-5221 and E4D-5222) and traditional maintenance activities should be adequate to assure '
- C) system integrity.
l l
Conclusions and Recommendations ic) Based-on the above evaluation, it is concluded that for the examinations discussed above, the Code requirements are impractical .
It is further concluded that other examinations discussed in die 4
evaluation will provide necessary added assurance of structural l reliabil i ty. Therefore, it is recommended that relief be granted I from the Code requirements to hydrostatically test the reactor C) coolant punip seals and component cooling lines.
References
- O References 1 and 7.
.O C) 44 4--umvm----gg w-*-w-w e- %> e+ w++ .y -=+w- t g ,V--1m ww
0
- 3. Hydro Relief Request Nos.1, 2, and 8, Class 1 and 2 Pipe Sections Not Testable with Present Configurations O
Code Requirement i IWB-5222(a ): The system hydrostatic test may be conducted at any test pressure spect fled in Table IWB-5220-1 corresponding to the selected test temperature, provided the requirements of IWB-5230 O are met for all ferritic steel components within the boundary of the system (or portion of system) subject to the test pressure (see IW A-5245) .
IWC-5222(a ): The system hydrostatic test pressure shall be' at least 1.10 times the system pressure Psv for systems with design O temperature of 2000F (930C) or less, and at least 1.25 times the systeen pressure Psv for systems with design temperature above 2000F
( 9300). The system pressure Psv shall be the lowest pressure setting among the number of safety or relief valves provided for overpressure protection within tha boundary of the system to be tested. For systems (or portions of systems) not provided with O safety or relief valves, the system design pressure Pd shall be substituted for P sv-
- *"* "9 " "
O Relief is requested from the Code hydrostatic tests of the following piping sections:
Hydro Relief No. Attm t.
- Pipe Section Class O
1 1-1 FCV-CS01 to CS 0018 2 1 1-2 FCV-CS02 to CS 0023 2 1 1-3 FCV-CS03 to CS 0028 2 2 2-8 YC 8152, 8153 to IWO 187 2 1 3-2 VC-LCY 112D, E to VC 8546 2 0 1 3-6 MOV-VC 8110 to VC 84798 2 2 3-7 VC 8413 L VC 8101 2 1 5-5 MOV-SI 8806 to SI 8926 2 1 5-6 A0Y-SI 8883 to SI 8912 2 1 6-2 MOV-SI 8809A,B to SI 8957 A,8 1,2 1 6-4 MOV-SI '812A to SI 8958 2
.O. 6-5 1 MOV-SI 8812A to MOV-SI 88128 2 8 14-55 SS-0015 to XCV-SS-427 2 8 14-74-1 SS-0015 to XCV-SS-427 2 O
- Refers to attachments of P& ids to the licensee's ISI program, Reference 1.
t O -45 m __ __ _ - - - _
'O Proposed Alternative Examination Those sections that can be lined up with the volume control tank (attachments 14-55 and 14-74-1) or RWST (attachments 1-1,1-2, O l-3, 3-2, 5-5, 6-4, and 6-5) will be tested during the tank test.
Other sections (attachments 2-8, 3-6, 5-6, and 6-2) will be tested at normal operating pressure per IWC-5221.
Licensee's Basis for Requesting Relief O
All the above piping sections are required to be tested to a pressure that is higher than the maximum pressure of the available pressure source (pumps, tanks, lower design pressure piping). In addition, several of the subject lines do not contain fittings to attach a hydro punp (attachments 3-6, 6-2, and 6-5). The itcensee O believes that any requirement to install pressure taps or to remove check valve internals poses undue hardship.
Evaluation O
The only ways to test the subject piping sections to Code requirements are to install hydrostatic punp fittings or to remove check valve internals. The licensee has objected to these methods of achieving the required hydrostatic tests, and instead, states that the proposed alternative examinations will be adequate to o determine system integrity. Based on the fact that many of these sections will be Code examined by nondestructive examinations and on the licensee's rationale, the relief requested and the proposed alternatives should be accepted.
O Conclusions and Recommendations Based on the above evaluation, it is concluded that for the examinations discussed above, the Code requirements are impractical .
It is further concluded that the alternative examinations discussed O above will provide necessary added assurance of structural reli-ability. Therefore, the following are recommended:
(a) Relief should be granted from the Code requirements to hydrostatically test the subject piping sections.
O (b) The alternative tests proposed by the licensee should be performed in lieu of the Code testing.
Re ferences O
References 1 and 7.
O 46
O
- 4. Hydro Relief Request Nos. 3 and 6, Various Class 3 Piping Sections Code Requirement O
IWD-5223(a ): The system hydrostatic test pressure shall be at least 1.10 times the system pressure Psv for systems with design temperature of 2000F (930C) or less, and at least 1.25 times the system pressure Psv for systems with design temperature above 2000F
( 930C) . The system pressure P y shall be the lowest pressure O setting among the number of safety or relief valves provided for overpressure protection within the boundary of the system to be tested. For systems (or portions of systems) not provided with safety or relief valves, the system design pressure Pd shall be substituted for Psy.
O Code Relief Request Relief is requested from the Code hydrostatic tests of the f 11 wing class 3 piping sections:
O Hydro l Relief No. Attm t.* Pipe Section l 3 3-5 FCV-VC0111 A to VC8429 3 7-1 MOV-FW0057 to FWOO69 O MOV-P40056 to F40069 M0V-FW0055 to FW0068 M0Y-FW0054 to FW0068 3 7-3 MOV-FW0053 to FW0067 MOV-FW0052 to FWOO67 3 7-4 M0V-FW0051 to FWOO66 O MOV-FWOO50 to FWOO66 ,
8-1 SW0001 to Pump SWOO3 SW0004 to Pump SW002 SW0007 to Pump SW001 3 9-66 Line CC032 O Line CC003 Line CC001 Line CC012 3 9-67 Line CC032 l Line CC055 i 1
q Line CC056
" f a Line CC057 )
Line CC012 l
O
- Refers to attachments of P& ids to the licensee's ISI program, Reference 1.
O i
'O' Hydro .
Relief No. Attm t.
- Pipe Section 3 9-523 Line CC032 Line CC055 O Line CC056 Line CC057 Line CC012 3 10-1 Boric Acid Transfer Pumps 6 12-1 CC-Oll7 to CC-9441 O 6 12-2 CC-0006 to CC-9454 Proposed Alternative Examinations O
Testing for evidence of leakage will be performed at their noainal operating pressures in accordance with IWD-5222.
Licensee's Basis for Requesting Relief Hydrostatic testing of these portions of the Class 3 system is restricted due to the limiting design configurations of the pumps, piping, and valves. Mditionally, some portions of systems are O connected to common piping which cannot be isolated from the other unit without rendering those systems inoperable.. Also, hydrostatic testing the CC Surge Tank fill lines ( Attachments 12-1,12-2) could result in contamination of the station's pure water system with chromates from the surge tanks. The proposed alternative exami-nations will provide the desired results if leakage is present when O this testing is performed for the inspection interval.
Eval uation O Testing these piping sections would require modifications and risks to the plant that are not warranted by the benefits of the required hydrostatic tests. Therefore, the relief requested and the proposed alternative examinations should be accepted.
O
- Refers to attachments of P& ids to the licensee's ISI program, Reference 1.
O O 48
~
lO i
i
! Conclusions and Recommendations
. Based onLthe above evaluation, it'is concluded that for the
!C) examinations discussed above, the Code requirements 'are impractical .
- ' -It is further concluded that the _ alternative examinations discussed above will provide necessary added assurance of ' structural reli-l ability. Therefore, the following are recommended
- C) (a) Relief :hould be granted from the Code requirements to hydrostatically. test the subject piping sections.
(b) The alternative tests proposed by the licensee should be perforned in-lieu -of the Code testing.
,; C) -
1 References 4
C) References 1 and 7.
i I
i
}C) i t
I 1
JC) i t
k
)
iG) i i
49 O
O 5.- Ittdro Relief Requist b. 5, Steam Generators and Attached Class 2 and Class 3 Piping O Code Requirement IWC-5222(a) and IWD-5223(a): The system hydrostatic test pressure shall be at least 1.10 times the system pressure Psv for systems with design temperature of 2000F (930C) or less, and at -
least 1.25 times the system pressure Psv for' systems with design O temperature above 2000F (930C). The system pressure Ps y shall be the lowest pressure setting among the nunber of safety or relief valves provided for overpressure protection within the boundary of the system to be tested. For systems (or portions of systems) not provided with safety or relief valves, the system design pressure Pd shall be substituted for Psv-O Code Relief Request Relief is requested from Code hydrostatic ' testing the O secondary sides of the steam generators and the attached piping (up to the 2nd isolation valves) of the following systems:
Attachmen ts* Piping Sections Class ,
11-20 Main -Steam 2 l O
11-20 Auxiliary Steam 2,3 11-45-1 Blowdown (to ist Isolation) . 2 11-22 Feedwater (to ist Isolation) 2
.O Proposed Alternative Examination The steam generators and the above described piping will be tested at the maximum normal operating pressure, about 1000 psig.
O Licensee's Basis for Requesting Relief Hydrostatic testing of these portions of the Class 2 system is restricted due to the limiting design configurations of the piping, s valves, and steam generator tubing differential pressure (600 O psi). In order to test this piping at the Code-required pressure ;
(1313 psig) the main steam safety relief valves must be gagged.
This puts the unit in a " limiting condition for operation." This "
condition is not considered safe. The proposed alternative test i l
O
- Refers to attachments of P& ids to the licensee's ISI program, Reference 1.
I i
j O 50 ?
1
O will provide the desired results if leakage is present when the testing is performed and will not affect safe operation.
"O Eval uation Because of design differential pressure and pressure-O temperature _ limitations, the primary system and the secondary sides of the steam generators would have to be above 2000F with the main steam relief valves gagged shut to obtain the 1313 psig hydrostatic test pressure. However, the 10-year hydrostatic test of steam generators and secondary piping is an important part of ensuring structural integrity of these systems since other nondestructive
- g examination requirements of the Code are quite limited. Al so ,- a number of defects in these systems have been discovered in other facil ities . Therefore, the -licensee should meet the Code require-ment for test pressure, even if he must (a) conduct the hydrostatic test when the reactor has been totally emptied of fuel for other inspections or (b) modify the technical specifications.
lO Conclusions and Recommendations to Based on the above evaluation, it is concluded that for the steam generators and attached piping described above, the Code-required hydrostatic tests are not impractical. Therefore, relief should not be granted from the above Code requirement.
- O References l
- l Reference 7. 1 0
- 1 1
..O 1
o
- O 51 i
- ~
O l REFERENCES 1
0 1. F. G. Lentine (CECO) to H. R. Denton (EC), June 27, 1983; Second Interval ISI Program attached. !
- 2. F. G. Lentine (CECO) to H. R. Denton (EC), June 27,1983; First- l Interval ISI Program Relief Requests. l O 3. F. G. Lentine (CECO) to H. R. Denton (EC), August 23, 1983; additional First-Interval ISI Program Relief Requests.
- 4. S. A. Yarga (mC) to D. L. Farrar (CECO), December 28, 1984; relief from ASME Code Section XI.
O 5. S. A. Yarga (RC) to D. L. Farrar (CECO), May 11, 1934; Request for Additional Infornation (RAI).
- 6. R. N. Cascarano (CECO) to H. R. Denton (EC), June 26, 1984; partial response to RAI.
O 7. R. N. Cascarano (CECO) to H. R. Denton (EC), August 14, 1984; completion of response to RAI.
- 8. J. A. Jones Applied Research Services Company, "MINAC," an unpublished report on the use of MINAC Radiographic Systems available from J. A.
n Jones Applied Research Services Company,1300 Harris Boulevard, P.O.
Box 217097, Charlotte, North Carolina 28221, (704)S97-6100.
- 9. M. E. Lapides, " Radiographic Detection of Intergranular Stress Corrosion Cracking: Analysis, Qualification, and Field Testing," EPRI l NP-3164-SR, Electric Power Research Institute, October 1983.
,d
- 10. M. E. Lapides, " Radiographic Detection of Crack-Like Defects in Thick !
Sections," Materials Evaluation , May 1984, Vol . 42, MJmber 6. l O
O i O
52 O