ML20211P006
| ML20211P006 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 09/07/1999 |
| From: | ENTERGY OPERATIONS, INC. |
| To: | |
| Shared Package | |
| ML20211N991 | List: |
| References | |
| NUDOCS 9909130119 | |
| Download: ML20211P006 (12) | |
Text
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- s PROPOSED TECHNICAL SPECEJCATION CHANGES 9909130119 990907 PDR ADOCK 05000313 P
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a.
The first semple inspaction during each inservice inspection (subssquant to the baseline inspection) of each steam generator shall includes 1.
All nonplugged tubes that previously had detectable wall l
penetrations (>20%), except tubes in which the wall penetration has been spanned by a sleeve, and 2.
At least.50% of the tubes inspected shall be in those areas where experience has indicated potential problems, except 4
where specific groups are inspected per Specification 4.18.3.a.3.
A tube inspection (pursuant to Specification 4.18.5.a.9) shall be f
performed on each selected tube.
If any selected tube does not perndt the passage of the eddy current probe for a tube inspection, this shall be recorded and an adjacent tube shall be selected and subjected to a tube inspection.
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3.
Tubes in the following groups may be excluded from the first random sample if all tubes in a group in both steam generators are inspected. The inspection may be concentrated on those portions of the tubes where f
imperfections were previously found. No credit will be l
taken for these tubes in reeting minimum sample size requirements. Where only a portion of the tube is inspected, the remainder of the tube will be subjected to
{
the random inspection.
(1)
Group A-1:
Tubes within one, two or three rows of the open inspection lane.
(2)
Group A-2:
Unplugged tubes with sleeves installed.
)
(3)
Group A-3:
Tubes in the wedge-shaped group on either side of the lane region (Group A-1) as defined by Figure 4.18.1.
4.
Implementation of the upper tubesheet ODIGA alternate repair l
criteria requires a 100% bobbin coil inspection of the non-plugged and non-sleeved tubes, spanning the defined region of the upper tubesheet, during all subsequent SG inspection intervals pursuant to 4.18.4.
Tubes with ODIGA identified during previoas inspections which meet the criteria to remain in service will not be included when calculating the inspection category for the OTSG.
The defined region begins one inch above the upper tubesheet secondary face and ends at the nearest tube roll transition.
ODIGA indications detected by the bobbin coil probe shall be characterized using rotating coil probes in accordance with topical report BAW-10235P, Revision 1.
b.
All tubes which have been repaired using the reroll process will have j
'the new roll area inu?ected during the inservice inspection.
c.
The second and third sample inspections during each inservice inspection as required by Table 4.10-2 may be less than a full tube inspection by concentrating the inspection on those areas of
'the tube sheet array and on those portions of the tubes where tubes with imperfections were previously found.
Amendment No. 24,44,46, M6, 110jl i
b
o
.A 4;18.5
^ Acesptanca criteria
_a.
'As used in_this specifications a.
~.,
- 1. '
Tubing or Tube means that portion of the tube or sleeve which forms the primary system to secondary system pressure boundary.
2.
Imperfection means'an exception to the dimensions, finish or contour of a tube from that required by fabrication drawings or specifications.
Eddy. current testing indications below 20% of the nominal tube wall thickness, if detectable, may be considered as imperfections.
~
3.
Degradation means a service-induced cracking, wastage, wear or general corrosion occurring on either the inside or outside of a tube.
4.
Degraded Tube means a tube containing imperfections s 20% of the nominal wall thickness caused by degradation, except where all degradation has been spanned by the installation of a sleeve.
5.
% Degradation means the percentage of the tube wall thickness affected or removed by degradation.
6.
Defect means an imperfection of such severity that it exceeds the plugging limit except where the imperfection has.been spanned by the installation of a sleeve. A tube containing a defect in its pressure boundary is defective.
7.
Pluqqing Limit means the imperfection depth at or beyond 40% of the nominal tube wall thickness for which the tube shall be sleeved, rerolled, or removed from service because it may become unserviceable prior to the next inspection.
This does not apply to ODIGA indications within the defined region of the upper j
tubesheet. These indications shall be assessed for continued I
plant operation in accordance with topical report BAW-10235P, Revision 1.
I The reroll repair process will only be used to repair tubes with defects in the upper tubesheet area.
The reroll repair process will be performed only once per steam generator tube using a 1 inch roll length. The new roll area must be free of detectable degradation in order for the repair to be considered acceptable.
The reroll repair process is described in the topical report, BAW-10232P, Revision 00.
8.
Unserviceable describes the condition of a tube if it leaks or contains a defect large enough to affect its structural integrity in the event of an Operating Basis Earthquake, a loss-of-coolant accident, or a steam line or feedwater line break as specified in Specification 4.18.4.c.
9.
Tube Inspection means an inspection of the steam generator tube from the point of entry completely to the point of exit.
For tubes that have been repaired by the reroll process within the upper tubesheet, that portion of the tube above l
the new roll can be excluded from future periodic inspection i
requirements because it is no longer part of the pressure boundary once the repair roll is installed.
b.
The steam generator shall be determined operable af ter completing
-the corresponding actions (plug, reroll, or sleeve all tubes exceeding _the plugging limit and all tubes centaining through-wall cracks) required by Table 4.18-2.
Amendment No. 24,4h86,M6,M4,MO 110m i
4.18.6 Rrporte Following each inservice inspection of steam generator tubes, the complete result,s of the inspection shall be reported to the NRC.
This report, to be
submitted within 90 days of. inspection completion, shall include:
l
~
a.
. Number and extent of tubes inspected; b.
Location and percent of wall-thickness penetration for each indication of an imperfections c.
Identification of tubes plugged and tubes sleeved; d.
Number.of tubes repaired by rerolling and.numoer of indications detected inLthe new roll area of the repaired tubes; and Summary of the condition monitoring and the operational assessment e.
results (including growth) when applying the upper tubesheet ODIGA alternate repair criteria.
'This report shall be in addition to'a Special Report (per Specification
'6.12;5.d) required for the results of steam generator tube inspections which fall into Category C-3 as denoted in Table 4.18-2.
The Commission shall be notified of the results of steam generator tube inspections which fall into Category C-3 prior to resumption of plant operation. The written Special Report shall provide a description of investigations conducted to deterndne cause of the tube degradation and corrective measures taken to prevent recurrence.
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l Amendment No. B4,44,M,M6,H4, 11Om1 M9, %0,4% ~
I Besss The surveillance requirements for inspection of the steam generator tubes
', ensure,that the structural integrity of this portion of the RCS will be maintained. The program for inservice inspection of steam generator tubes is based on a modification of Regulatory Guide 1.83, Revision 1.
Inservice inspection of steam generator tubing is essential in order to nmintain surveillance of the conditions of the tubes in the event that there is evidence of mechanical damage or progressive degradation due to design, manufacturing errors, or inservice conditions that lead to corrosion.
Inservice inspection of steam generator tubing also provides a means of characterizing the nature and cause of any tube degradation so that corrective measures can be taken.
In. general, steam generator tubes that are degraded beyond the repair limit can either be plugged, sleeved, or rerolled. The steam generator (SG) tubes that are plugged are removed from service by the installation of plugs at both ends of the associated tube and thus completely removing the tube from
-service. When the upper tubesheet outer diameter intergranular attack (ODIGA) alternate repair criteria is applied, indications found within the defined region of the upper tubesheet may be left in service under the guidelines of topical report BAW-10235P, Revision 1.
The defined region begins one inch above the upper tubesheet secondary face and ends at the nearest tube roll transition.
Following a SG inspection, an operational assessment is performed to ensure primary-to-secondary leak rates will be maintained within the assumptions of the accident analysis.
Degraded steam generator tubes can aJso be repaired by the installation of sleeves which span the area of degradation and serve as a replacement pressure boundary for the degraded' portion of the tube, thus permitting the tube to remain in service.
Degraded steam generator tubes can also be repaired by the rerolling of the tube in the upper tubesheet to create a new roll area and pressure boundary for the tube. The rerolling methodology establishes a new pressure boundary below the degradation, thus permitting the tube to remain in service.
The degraded tube above the new roll area can be excluded from future periodic inspection requirements because it is no longer part of the pressure boundary once the repair roll is installed in the upper tubesheet. The rerolling repair process will only be used to repair defects in the upper tubesheet in accordance with BAW-10232P, Revision 00.
All tubes which have been repaired using the reroll process will have the new roll area inspected during future inservice inspections.
Defective or degraded tube indications found in the new roll and any indications found in the original roll need not be included in determining the Inspection Results Category for the generator inspection.
The reroll repair process will only be used to repair tubes with defects in the upper tubesheet area. 'The reroll repair process will be performed only once per steam generator tube using a 1 inch roll length.
Thus, multiple applications of the reroll process to any individual tube is not acceptable.
The new roll area must be free of detectable degradation in order for the repair to be considered acceptable. After the new roll area is initially deemed acceptable, future degradation in the new roll area will be analyzed to determine if the tube is defective and needs to be removed from service.
The reroll repair process is described in the topical report, BAW-10232P, Revision 00.
Amendment No. 34,M,86,446,444, 110n 4%, %99,4%
,J t.
l MARKUP OF CURRENT ANO-1 TECHNICAL SPECIFICATIONS (FORINFORMATION ONLY) 1 l
Legend Strike-through Deleted Text
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Double Underline =
Added Text Shaded Text being deleted from current page and being moved to another
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Boxed Text being added to current page from another page
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l a.
The first atmple inspection during each inservice inspection (subsequsnt to the baselina inspection) of each steam generator shall include 1.
All nonplugged tubes that previously had detectable wall penetrations (>20%), except tubes in which the wall penetration has been spanned by a sleeve, and 2.
At least 50% of the tubes inspected shall be in those areas where experience has indicated potential problems, except where specific groups are inspected per Specification 4.18.3.a.3.
A tube inspection (pursuant to Specification 4.18.5.a.9) shall be performed on each selected tube.
If any selected tube does not permit the passage of the eddy current probe for a tube inspection, this shall be recorded and an adjacent tube shall be selected and subjected to a tube inspection.
3.
Tubes in the following groups may be excluded from the first random sample if all tubes in a group in both steam generators are inspected.
The inspection may be concentrated on those portions of the tubes where imperfections were previously found. No credit will be taken for these tubes in meeting minimum sample size requirements. Where only a portion of the tube is inspected, the remainder of the tube will be subjected to l
the random inspection.
I (1)
Group A-1:
Tubes within one, two or three rows of the open inspection lane.
l (2)
Group A-2:
Unplugged tubes with sleeves installed.
]
(3)
Group A-3:
Tubes in the wedge-shaped group on either side of the lane region (Group A-1) as defined by Figure 4.18.1.
4.
Implementation of the upp_er tubesheet ODIGA alternate repair criteria requires a 100% bobbin coil inspection of the non plyggeg gnd_,Jigq-sleeved tubesu pannina the d.e11ned region of. the upp,e,I s
pubesheet, during_all subsequent SG inspection interyals_ pursuant to 4.18.4.
Tubes with ODIGA identified durina, previous
)
inspections which meet the criteria to remain in servic.e will not be included when calculating the inspection cateoorv for the_OISG 1
The defined recion begip_s one ingh_above the upper tubesheet sec_ondary face and ends at the_Re3 Lest tube _ Loll transitiona ODIGA indications detected by the bobbin coil _ probe shall be characterized using rotatino coil probes in accordance with topical report BAW-10235P, Revision 1.
b.
All tubes which have been repaired using the reroll process will have the new roll area inspected during the inservice inspection.
c.
The second and third sample inspections during each inservice inspection as required by Table 4.18-2 may be less than a full tube inspection by concentrating the inspection on those areas of the tube sheet array and on those portions of the tubes where
. tubes with imperfections were previously found.
Amendment No. G4,44,86,406 110jl L.
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4.18.5 Acceptance criteria a.
As used in this specification:
-1.
Tubing or Tube means that portion of the tube or sleeve which forms the primary system to secondary system pressure boundary.
2.
Imperfection means an exception to the dimensions, finish or contour of a tube from that required by fabrication drawings or specifications.
Eddy current testing indications below 20% of the nominal tube wall thickness, if detectable, may be considered as imperfections.
3.
Degradation means a service-induced cracking, wastage, wear or general corrosion occurring on either the inside or outside of a tube.
4.
Degraded Tube means a tube containing imperfections j% 20% of l
the nominal wall thickness caused by degradation, except where all degradation has been spanned by the installation of a sleeve.
5.
% Degradation means the percentage of the tube wall thickness affected or removed by degradation.
]
6.
Defect means an imperfection of such severity that it i
exceeds the plugging limit except where the imperfection has been spanned by the installation of a sleeve. A tube containing a defect in its pressure boundary is defective.
7.
Plugging Limit means the imperfection depth at or beyond 40% og
,tJhrlominal tube wall thickness fq1 m
which the tube shall be :::tered t: :::vice:bility by the inct:llati:n f a sleeved, rerolled, or removed from service because it may become unserviceable prior to the next inspection,i,t 4t 1: ::;u:1 to 400 cf th; n:=in:1 tub.::11 thichn ::. This does not apply to the oDIGA indiceAions within the defined recion of the upper tubesheet. These indications shall be assessed _ Lor continued plattt_oppg.ation in accordance with topical repor_t BAW-10235P, Revision 11
. Amendment No. 44,44,M,M6,H4,4%
110m l
en.-
.+
i Tha reroll repair process will only be used to repair tubes with I
dafects in tha upper tubesheet area.- The raroll repair process will be performed only once per steam generator tube using a 1 inch roll length. The new roll area must be free of detectable degradation in order for the repair to be considered acceptable.
The reroll' repair process is described in the topical report, BAW-10232P, Revision 00.
8.
Unserviceable describes the condition of a tube if it leaks or contains a defect large enough to affect its structural integrity in the event of an Operating Basis Earthquake, a'
loss-of-coolant accident, or a steam line or feedwater line break as-specified in Specification 4.18.4.c.
9.
Tube Inspection means an inspection of the oteam generator tube from the point of entry completely to the point of exit.
For tubes that have been repaired by the reroll process within the upper tubesheet, that portion of the tube above the new roll can be excluded from future periodic inspection requirements because it is no longer part of the pressure boundary once the repair roll is installed.
b.
The steam generator shall be deterndned operable af ter completing the corresponding actions ' (plug, reroll, or sleeve all tubes exceeding the plugging limit and all tubes containing through-wall cracks) required by Table 4.18-2.
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c.
Idtntification of tubes plugged and tubes sleeved;-end d.
Number of tubes repaired by rerolling and number of indications detected in the new roll area of the repaired tubesvt=and
~
e.
Summary _of the condition monitoring _and the ope. rational assessment results (including _srowth) when ap, plying _the upper tubesheet ODIGA alternate repair criteria.
This report shall be in addition to a Special Report (per Specification 6.12.5.d) required for the results of steam generator tube inspections which fall into Category C-3 as denoted in Table 4.18-2.
The Commission shall be notified of the results of steam generator tube inspections which fall into Category C-3 prior to resumption of plant operation. The written Special Report shall provide a description of investigations conducted to deterndne cause of the tube degradation and corrective measures taken to prevent recurrence.
1 l
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[df TNumbeiof tubesTispaired b9"reiolling and nLrWeForindications deteeted in the new roll 1 <
i ; area;of the. repaired tubest i f
a u,__m iThisjepsit Tshall beIinf additloh toVS;iecist' Rep 6rt (psr SpecificatioE6.12;53) fequir'ed for the fesUlts of /
' steam gen lerator tube inspections;which fall into Category C-3 la's denoted in Table 4.18-2J The i Commission 'shall be notified of the;results of steam generator tube inspections which fall. into Category J C-3' prior to resumption of plant operation: The written Special Report shall provide a description.of L ~
^
. investigations conducted to' determine cause of the tube l degradation.and correctivs measures taken tol prevent recurrence._
m
_m m
m Bases The surveillance requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the RCS will be maintained. The program for inservice inspection of steam generator tubes is based on a modification of Regulatory Guide 1.83, Revision 1. Inservice inspection of i
steam generator tubing is essential in order to maintain surveillance of the conditions of the tubes in the j
event that there is evidence of mechanical damage or progressive degradation due to design, manufacturing errors, or inservice conditions that lead to corrosion. Inservice inspection of steam generator tubing also provides a means of characterizing the nature and cause of any tube degradation so that corrective measures can be taken.
hlseneraksSteam generator tubes that are degraded beyond the repair limit can either be plugged, sleeved, or rerolled. The steam generator (SQltubes that are plugged are removed from service by the installation of plugs at both ends of the associated tube and thus completely removing the tube from service. When the upper tubesheet outer diameter inter _ granular _attagk__{0DIGAL al_ ternate repair criteria is applied,_ indications found within the defined gegion of the upper tubesheet may_be_left in_serviggunder_t;he cuide_ lines _ of Logical report BAW-10235L_BeX sjon 1.
The defined region begins one inch j
i above the upper tubesheet secondary _ face and ends at the nearest tube roll transition.
Following a SG inspection, an operationaLassessment is gerformed to ensure primary-to-seg_ondary_ leak rates will be maintained within the assumptions of the accident ana lysis.
Degraded steam generator tubes can also be repaired by the installation of sleeves which span the area of degradation and serve as a replacement pressure boundary for the degraded portion of the tube, thus j
permitting the tube to remain in service.
j Degraded steam generator tubes can also be repaired by the rerolling of the tube in the upper tubesheet to create a new roll area and pressure boundary for the tube. The rerolling methodology establishes a i
new pressure boundary below the degradation, thus permitting the tube to remain in service. The degraded tube above the new roll area can be excluded from future periodic inspection requirements because it is no longer part of the pressure boundary once the repair rollis installed in the upper tubesheet. The rerolling repair process will only be used to repair defects in the upper tubesheet in accordance with BAW-10232P, Revision 00.
All tubes which have been repaired using the reroll process will have the new roll area inspected during future inservice inspections. Defective or degraded tube indications found in the new roll and any indications found in the original roll need not be included in determining the inspection Results Category for the generator inspection.
The reroll repair process will only be used to repair tubes with defects in the upper tubesheet area. The reroll repair process will be performed only once per steam generator tube using a 1 inch roll length.
Thus, multiple applications of the reroll process to any individual tube is not acceptabie. The new roll area must be free of detectable degradation in order for the repair to be considered acceptable. After the new roll area is initially deemed acceptable, future degradation in the new roll area will be analyzed to determine if the tube is defective and needs to be removed from service. The reroll repair process is described in the topical report, BAW-10232P, Revision 00.
Amendment No. 24,44,86,406,448, 110n 472,490,494