ML20107J962

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Proposed Tech Specs Re L* Tubesheet Region Cycle 11 Specific Plugging Criterion
ML20107J962
Person / Time
Site: Farley Southern Nuclear icon.png
Issue date: 04/23/1996
From:
SOUTHERN NUCLEAR OPERATING CO.
To:
Shared Package
ML20107J957 List:
References
NUDOCS 9604250335
Download: ML20107J962 (19)
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Text

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Technical Soecification Pages Page Channe Instructions Page 3/4 4-9 Replace Page 3/4 4-11 Replace Page 3/4 4-12a Replace Page 3/4 4-12b Replace Page 3/4 4-13 Replace Page 3/4 4-13a Replace Page B3/4 4-3a Replace Page B3/4 4-3b Replace I

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l 9604250335 960423 PDR ADOCK 05000364' p PDR

. REACTOR' COOLANT SYSTEM 3/4.4.6 STEAM GENERATORS LIMITING CONDITION FOR OPERATION 3.4.6 Each steam generator shall be OPERABLE.

APPLICABILITY: MODES 1, 2, 3 and 4.

i ACTION:

With one or more steam generators inoperable, restore the inoperable generator (s) to OPERABLE status prior to increasing Tavg above 200'F.

1 SURVEILLANCE REQUIREMENTS 4.4.6.0 Each steam generator shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the

requirements of Specification 4.0.5.

d 4.4.6.1 Steam Generator Sample Selection and Inspection - Each steam

, generator shall be determined OPERABLE during shutdown by selecting and inspecting at least the minimum number of steam generators specified in Table 4.4-1.

4.4.6.2.1 Steam Generator Tube # Sample Selection and Inspection - The steam generator tube minimum sample size, inspection result classification,

and the corresponding action required shall be as specified in Table 4.4-2.

The inservice inspection of steam generator tubes shall be performed at the frequencies specified in Specification 4.4.6.3 and the inspected tubes shall be verified acceptable per the acceptance criteria of Specification 4.4.6.4. The tubes selected for each inservice inspection shall include at least 3% of the total number of tubes in all steam generators. Selection of tubes to be inspected is not af fected by the F*/L*n designation. When l applying the exceptions of 4.4.6.2.1.a through 4.4.6.2.1.c, previous defects or imperfections in the area repaired by sleeving are not considered an area requiring re-inspection. The tubes selected for these

=

inspections shall be selected on a random basis excepts

a. Where experience in similar plants with similar water chemistry  !

indicates critical areas to be inspected, then at least 50% of the tubes inspected shall be from these critical areas. ]

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b. The first sample of tubes selected for each inservice
inspection (subsequent to the preservice inspection) of each steam generator shall include
1. All nonplugged tubes that previously had detectable wall penetrations greater than 20%.
  1. When referring to a steam generator tube, the sleeve shall be considered a part of the tube if the tube has been repaired per Specification 4.4.6.4.a.9.

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    1. L* Criteria is applicable to Cycle 11 only. l l

l FARLEY-UNIT 2 3/4 4-9 AMENDMENT NO.

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, REACTOR COOLANT SYSTEM' SURVEILLANCE REQUIREMENTS (Continued)

I b I I I I Category Inspection Results C-1 Less than 5% of the total tubes inspected.are degraded tubes and none of the inspected tubes are defective.

C-2 One or more tubes, but not more than 1% of the total tubes inspected are defective, or between 5% and 10% of the total tubes inspected are degraded tubes.

C-3 More than 10% of the total tubes inspected are degraded tubes or more than 1% of the inspected tubes are defective.

Nota: In all inspections, previously degraded tubes or sleeves must exhibit significant (greater than 10%) further wall penetrations to be included in the'above percentage calculations.

4.4.6.2.2 Steam Generator F*/L*n Tube Inspection - In addition to the ndnimum sample size as determined by Specification 4.4.6.2.1, all F*/L*

tubes will be inspected within the tubesheet region. The results of this inspection will not be a cause for additional inspections per Table 4.4-2.

4.4.6.3 Inspection Frequencies - The above required inservice inspections of steam generator tubes shall be performed at the following frequencies

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a. The first inservice inspection shall be performed after 6 s

Ef fective Full Power Months but within 24 calendar months of j initial criticality. Subsequent inservice inspections shall be performed at intervals of not less than 12 nor more than 24 calendar months after the previous inspection. If two consecutive inspections following service under AVT conditions, not including the preservice inspection, result in all inspection results falling into the C-1 category or if two consecutive inspections demonstrate that previously observed degradation has not continued and no additional degradation has occurred, the inspection interval may be extended to a maximum of once per 40 months.

j b. If the results of the inservice inspection of a steam generator conducted in accordance with Table 4.4-2 at 40 month intervals fall in Category C-3, the inspection frequency shall be increased to at least once per 20 months. The increase in inspection frequency shall apply until the subsequent i inspections satisfy the criteria of Specification 4.4.6.3.a; ,

the interval may then be extended to a maximum of once per 40 l months. I 1

c. Additional, unscheduled inservice inspections shall be performed on each steam generator in accordance with the first sample inspection specified in Table 4.4-2 during the shutdown subsequent to any of the following conditions:

N# L* Criteria is applicable to Cycle 11 only. l j EARLEY-UNIT 2 3/4 4-11 AMENDMENT NO. l

, REACTOR COOLANT SYSTEM.

1

, SURVEILLANCE REQUIREMENTS-(Continued) 1

6. Plugging or Repair Limit means the imperfection depth at j or beyond which the tube shall be repaired (i.e.,

]

sleeved) or removed from service by plugging and is i

greater than or equal to 40% of.the nominal tube wall i thickness. This definition does not apply for tubes that meet the F*/L*se criteria. For a tube that has been.

sleeved with a mechanical joint sleeve, through wall penetration of greater than or equal to-31% of sleeve  ;

nominal wall thickness in the sleeve requires the tube to

be removed from service by plugging. For a tube that has ,

been sleeved with a welded joint sleeve, through wall ,

penetration greater than or equal to 37% of sleeve 4

nominal wall thicknese in the sleeve between the weld 1

joints requires the tube to be removed from service by  ;

plugging. This definition does not apply to tube support .

plate intersections for which the voltage-based repair  !

criteria are being applied. Refer to 4.4.6.4.a.14 for l the repair limit applicable to these intersections.

7. Unserviceable de.cribes the condition of a tube or sleeve if it leaks or contains a defect large enough to affect l 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 4.4.6.3.c, above.
8. Tube Inspection means an inspection of the steam generator tube from the point of entry (hot leg side) completely around the U-bend to the top support of the cold leg. For a tube that has been repaired by sleeving, the tube inspection should include the sleeved portion of the tube.
9. Tube Repair refers to mechanical sleeving, as described by Westinghouse report WCAP-11178, Rev. 1, or laser welded sleeving as cescribed by Westinghouse report WCAP-12672, which is used to maintain a tube in service or +

return a tube to service. This includes the removal of plugs that were installed as a corrective or preventive measure. I

    1. L* Criteria is applicable to Cycle 11 only. l FARLEY-UNIT 2. 3/4 4-12a AMENDMENT NO.

l

, REACTOR COOLANT SYSTEM '

, SURVEILLANCC REQUIREMENTS (Continued)

10. Preservice Inspection means an inspection of the full length of each tube in each steam generator performed by eddy current techniques prior to service to establish a baseline condition of-the tubing. This inspection shall be performed after the field hydrostatic test and prior.to initial POWER OPERATION using the equipment and techniques expected to be used during subsequent inservice inspections.

11 F* Distance is the distance of the expanded portion of a tube which provides a sufficient length of undegraded tube expansionsto resist pullout of the tube from the tubesheet. The F* distance is equal to 1.79 inches and is measured down from the top of the tubesheet or the bottom of the roll transition, whichever is lower in elevation.

12. F* Tube is a tube:

a).with degradation equal to or greater than 40% below the F*

distance, and b) which has no indication of imperfections greater than or equal to 20% of nominal wall thickness within the F*

distance, and c) that remains inservice.

If the above criteria cannot be met, then the L* tube criteria may be applied or the tube must be plugged or repaired.

13. L* Length,, is the length of the expanded portion of the tube into the tube sheet from the bottom of the rolled transition or the top i of the tube sheet, which ever is lower, that has been determined to I be 1.45 inches.
14. L* Tube ,,: a) is a tube with degradation equal or greater than 40%

below the L* 1ength and not degraded within the L* length; b) the eddy current indication of degradation below the L* length must be determined to be the result of cracks with an orientation no greater than 15 degrees from axial; c) the L* criteria shall be limited to a maximum of 600 tube ends per steam generator; d) tubes qualifying as F* tubes are not classified as L* tubes; e) a minimum of 3.1 inches of the tube into the tubesheet from the top of tubesheet or bottom of the rolled transition, which ever is lower, c shall be inspected using rotating pancake coil eddy current technique or an inspection method shown to give equivalent or better information on the orientation and length of axial cracks; f) a minimum aggregate of 2.07 inches of sound roll expansion; g) a

. maximum crack length of .39 inches; h) a maximum of 5 distinct indications with a single band of tube degradation; and 1) that remains in service.

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    1. L* Criteria is applicable to Cycle 11 only. l 1

FARLEY-UNIT 2 3/4 4-12b AMENDMENT NO. l l

. . . . = -

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REACTOR COOLANT SYSTEM l

SURVEILLANCE REQUIREMENTS (Continued) 4

15. Tube Expansion is that portion of a tube which has been increased in diameter by a rolling process such that no crevice exists between the outside diameter of the tube and the hole in the tubesheet.
16. Tube Support Plate' Plugging Limit is used for the disposition of a steam generator tube for continued i service that is experiencing outside diameter stress corrosion cracking confined within the thickness of the
tube support plates.. These criteria are applicable for the Eleventh Cycle only. At tube support plate intersections, the repair limit is based on maintaining steam generator tube serviceability as described below f a. Degradation attributed to outside diameter stress corrosion cracking within the bounds of the tube support plate with bobbin voltage less than or equal to 2.0 volts will be allowed to remain in service.

, b. Degradation attributed to outside diameter stress corrosion cracking within the bounds of the tube

support plate with bobbin voltage greater than 2.0 volts will be repaired or plugged except as noted in 4.4.6.4.a.14.c below.

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c. Indications of potential degradation attributed to outside diameter stress corrosion cracking within the bounds of the tube support plate with a bobbin voltage greater than 2.0 volts but less than or equal to 5.6 volts may remain in service if a rotating pancake coil inspection does not detect degradation. Indications of outside diameter stress corrosion cracking degradation with a bobbin voltage greater than 5.6 volts will be plugged or repaired.

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b. The steam generator shall be determined OPERABLE after completing the corresponding actions (plug or repair of all tubes exceeding the plugging or repair limit) required by Table 4.4-2.

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J FARLEY - UNIT 2 3/4 4-13 AMENDMENT NO.

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~ r ,+a

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. REACTOR COOLANT SYSTEM SURVEILLANCE REQUIREMENTS (Continued)

  1. 1 I 4.4.6.5 Reports
a. Following each inservice inspection of steam generator tubes, the number of tubes plugged, repaired or designated F*/L*n in l ,

each steam generator shall be reported to the Commission within l 15 days of the completion of the inspection, plugging or repair effort.

b. The complete results of the steam generator tube and sleeve inservice inspection shall be submitted to the Commission in a Special Report pursuant to Specification 6.9.2 within 12 months following the completion of the inspection. This Special Report shall. include:
1. Number and extent of tubes and sleeves inspected.
2. Location and percent of wall-thickness penetration for each indication of an imperfection.
3. Identification of tubes plugged or repaired.
c. Results of steam generator tube inspections which fall into Category C-3 shall be considered a REPORTABLE EVENT and shall be reported pursuant to 10CFR50.73 prior to resumption of plant operation. The written report shall provide a description of investigations conducted to determine the.cause of the tube degradation and corrective measures taken to prevent recurrence,
d. For implementation of the voltage-based repair criteria to tube ,

support plate intersections, notify the staff prior to returning the steam generator to service (Mode 4) should any of the following conditions arise:

1. If estimated leakage based on the actual end-of-cycle voltage distribution would have exceeded the leak limit (for the postulated main steam line break utilizing licensing basis assumptions) during the previous operating cycle.
2. If circumferential crack-like indications are detected at the tube support plate intersections.
3. If indications are identified that extend beyond the confines of the tube support plate.
4. If the calculated conditional burst probability exceeds 1 x 10-2, notify the NRC and provide an assessment of the safety significance of the occurrence.
    1. L* Criteria-is applicable to Cycle 11 only. l FARLEY-UNIT 2 3/4'4-13a AMENDMENT NO.

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. REACTOR COOLANT SYSTEM

+

BASES 4

, I I I II I 4

b. Mechanical 2
1. Indications of degradation in the entire length of the sleeve must be evaluated against the sleeve plugging

, limit.

2. Indication of tube degradation of any type including a' l l complete guillotine break in the tube between the bottom-of the upper joint and the top of the lower roll expansion does not require that the tube be removed from service.
3. The tube plugging limit continues to apply to the portion j of-the tube in the entire upper joint region and in the ,

j lower roll expansion. As noted above, the sleeve i plugging limit applies to these areas also.

4. The tube. plugging limit continues to apply to that '

portion of the tube above the top of the upper joint.

b. Laser Welded
1. Indications of degradation in the length of the sleeve between the weld joints must be evaluated against the

, sleeve plugging limit.

2. Indicatjan Of tube degradation of any type including a complete break in the tube between the upper weld joint

, and the lower weld joint does not require that the tube

be removed from service.
3. At the weld joint, degradation must be evaluated in both the sleeve and tube.
4. In a joint with more than one weld, the weld closest to the end of the sleeve represents the joint to be inspected and the limit of the sleeve inspection. l l
5. The tube plugging limit continues to apply to the portion I of the tube above the upper weld joint and below the l lower weld joint. I F* tubes do not have to be plugged or repaired provided the remainder of the tube within the tubesheet that is above the F* distance is not degraded. The F* distance is equal to 1.79 inches and is measured down from the top of the tubesheet or the. bottom of the roll transition, 2

whichever is lower in elevation. Included in this distance is an allowance of 0.25 inch for eddy current elevation measurement uncertainty.

FARLEY-UNIT 2 B3/4 4-3a AMENDMENT NO.

, ., n, , . - . - 1

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, REACTOR COOLANT SYSTEM BASES L* is similar to F*; however, bands of axial degradation are allowed as long as sufficient non-degraded tubing is available to ensure structural and leakage integrity. L* criterion is only applicable for Unit 2 Cycle

11. Provided below is the Unit 2 Cycle 11 specific L* criterion:

Unit 2 Cycle 11 Specific L* Criterion Parameter Value Minimum distance of SRE 2.07 inches Maximum number of distinct degradation areas in 5 a band Maximum inclination angle within a single band 15 degrees Maximum crack length .39 inches Minimum distance of SRE from the bottom of the 1.45 inches transition roll to the top of the indication Steam generator tube inspections of operating plants have demonstrated the capability to reliably detect wastage type degradation that has penetrated 20% of the original tube wall thickness.

Whenever the results of any steam generator tubing inservice inspection fall into Category C-3, these results will be reported to the Commission pursuant to 10 CFR 50.~13 prior to resumption of plant operation. Such cases will be considered by the Commission on a case-by-case basis and may result in a requirement for analysis, laboratory examinations, tests, additional eddy-current inspection, and revision to the Technical Specifications, if necessary.

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FARLEY-UNIT 2 B3/4 4-3b AMENDMENT NO.

1

Attachment 3 Marked Un Proposed Technical Specification Pages 1

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,. ,,. . ;is**:n C0h u f 5'5*!a

. 3/4.4.6 STEAM GENERATOR $

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, LIMITING COWITION FOR OPERATION 4

3.a.6 Each steam generator shall be OPERABLE.

l APMICA8ILITY: 20E5 1, 2, 3 and 4 '

ACTION:

With one or more steam generators inoperable. restore the inoperable

) generator (s) to OPERA 8LE status prior to increasing favg above 200'F.

I, l 5'W EILLANCE REQUIREl(NTS i

i 4.4.6.0 . Each steas generator sna11 be demonstrated OPERA 8LE by performance of i the following augmented inservice inspection program and the requirements of Specification 4.0.5.

! 4.4.6.1 Steam Generator Sample Selection and Inspection . Each steam generator

shall be determined OPERABLE during shutdoem by selectTag and inspecting at

] least the minimum number of steam generators specified in Table 4.41.

4.4.6.2.1 Steam Generator Tube i Sample Selection and inspection - The steam geaerator tuce ninteurs sa.m;ie size, inspection result classification, and tne corresponding action required shall be as specified in Table 4.4 2. The inservice inspection of steam generator tubes shall be performed at the frequencies specified in Specification 4.4.6.3 and the inspected tubes shall be verified acceptable per the acceptance criterja et Sestffcatten 4.4.6.4. The tubes selected for each inservice inspection thall factude at least 35 of the i total ntenber of tubes in all steam generators. Selection of tubes to be i inspected is not af fected by the Ft des 19 nation. hen applying the exceptions of 4.4.5.2.1.a tnrough 4.4.6.2.14.g' previous defects er imperfections in the

.' area repaired by sleeving are not considered an aree requiring reinspection.

{$- A The tubes selected for these inspections sr.sil be selected on a randes basis

except

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a. Where esperience in similar plants with similar unter chemistry indicates critical areas to be inspected, then at least 505 of the
tubes inspected snall be from these critical areas.

i b. The first sample of tvoes selected for each inservice inspection (subsequent to the preservice inspection) of each steam generator shall include:

1. All nonplugged t. es that previously had detectable nell

, penetrations greater than 205.

i AWhen referring to a steam generator tube, the sleeve shall be considered a part of the tube if the tube has been repaired per Specification 4.4.6.4.a.9.

1 FAALET-UNIT 2 3/4 4.g AE NDf U T N0. ,

&l t!rY'o'r lS aff s..d,Ie N h cbe II o .

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,, ?EA:70A :::*. ANT SYs*EM t

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  • SURVEZL .ANCE REQUIREMENTS 10antinued)

Category Insoection mesults C-1 Less than Se of the total tubes inspected are degraded C-2 tubes and none of the insoected tubes are defective.

One or more tubes, but not more than it of .the totai tubes inspected are defective, or between St and 10% of the total C-3 tubes insoected are deeraded tubes.

t More than 100 of the totai tubes inspected are degraded tubes or more than 14 of the inspected tubes are defective.

4 Note:

exhibitInsignificant a11" inspections, previously degraded tubes or sleeves must 1

4 (greater than 100) included in the above percentage calculations.further wall penetrations to be i

1 4.4.6.2.2 Steam Generator F*[M#V/* Tube Inspection - In addition to the 4

minimum saeple size as determined by specification 4.4.6.2.1, all r*/ L p

tubes will be inspected within the tubesheet region.

inspection will not be a cause for additional inspections per TableThe results of this 4.4-2.

i 4.4.6.3 i Inspection Frequencies - The above required inservice i inspections frequencies: of steam generator tubes shall be performed at the following s.

The first inservice inspection shall bw performed after 6 2

I Effective initial Full Fower Meaths but withia 24 calender amonths of criticality. I Subsequent inservice inspections shall be performed at intervals of not less than 12 nor more than  ;

24 calendar months after the previous inspection. If two 1 consecutive inspections following service under AVT conditions, not including the preservice inspection, result in all inspection results falling into the C-1 category or if two consecutive inspections demonstrate that previously observed degradation has not continued and no additional degradation has occurred, the inspection interval may be extended to a ===4=== ef once per 40 months.

b.

! If the results of the inservice inspecties of a steam generater conducted is accordance with Table 4.4-2 at 40 meath intervals fall in Category C-3, the inspection frequency shall be increased to at least once per 20 months.

! The increase in inspection frequency shall apply until the l subsequest inspections satisfy the criteria of specification

4.4.6.3.as the interval may then be entended to a madmum of once per 40 months.

, c.

! Additional, unscheduled laservice inspections shall be performed on each steam generater la accordance with the

first sample inspection specified in Table 4.4-2 during the 4

1 shutdown subsequent to any of the fellowing conditions:

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  • 4 {

FARLrf-UNIT 2 3/4 4-11 ABENEMENT WO.106 l 1

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. . _ ~ . - - - . - . _ __ __ ___ _ _ _ _ _ - _ - - _ _ _ _ - _ _ _ _ _ _ - _ _ - _ _ _ - _ _ - _ - _ _ _ _ _ _ _ _ _ _

LD:"* a ::;p sys;pe J

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3.avttt:N.;g eggy:am erfs es-5.. .e s . -.

s. PI. seine er sesen t tami_t means the taperfection depta

, at er beyone watch sne tube shall be sepaised ti.e..

sleeved) er removed fsen service by pluggieg and is

/ eraetes thaa er equal to 404 et the assinet see e=11 L 'Y taistae n.1 e e m ' a =

@ u m m:

7 n'e t d e .,, ,*4.*o n do es ^ *y 6(f - d & t & c H:= ::;L = 2:h=,";u 7 W. :._. .. r^..

a i-i .. for i d e s T hai mgei 4Q -t h For a tube tAat has been sleeved with a l j , . mecAanisan joiht sleeve. through well penetrastes of M l' 8 0

  • greater than er equal to 316 of sleeve nonAnal well I

l p/L,.N C .

thicknass la the sleeve requires the tee to be removed from service by plugging. For a tube that has been I sleeved with a weided joint sleeve, through well l penetration greater than er equal to 376 of sleeve j amminai well thickasas La the sleeve between the weld joiats requires the tube to be removed from sesvies by j p1wsgitt. This dettaities does aet apply to tube supyst plate latessections for dish the voltage-based plugging criteria are betag applied. Refer to j e.4.6.4.a.14 iea t.he plugging limit applicable to theae 4

intersections.

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7. Unserviceable desesthee the eeedities of a tube or sleeve if it leaks or santatas a defset lasgo enough to l affect its structussi integrity La the event of as i operating Basis Berthquake, a less-of-coelaat accident.
. - , er a steaa line er feeduster lias break as spesified in
4. 4. 6. 3. e, above.

l I 0. Tube taspection osaas as inspeetles of the steen geasseter tube faesa the point of entry (het leg sidel

{ esap&ete&y around the 5=tead to the t4 seppese of the i sold leg. ret a tube that has been repetred by j sleeving, the tube inspecties should include the

sleeved perties si the tube.

i i 9. Tube possir refore to mechaatsal sleeving, as described i by Westinghouse report WCAp=11170, Rev.1, er laser

! welded sleeving as deessibed by Westinghouse report l WCAp-12612, which is used to malatata a tee is service

! er retuas a tube to servies. This laeludes the removal

! et plugs that were Lasta11ed as a corrective er preventive measu.se.

i CA J [5 alL d !c. e t. f cn .

l ^ FAAL8Y-UNIT 3 3/4 4-12a AMINEMErf 188 106 l i

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REA T:R 2:0LANT SYSTEM

, $URVEII,IRICE REQUIREMENT 3 (Continued)

10. Preservice' Inspection means an inspection of the full length of each tube in each steam generator performed j by eddy current techniques prior to service to

' establish a baseline condition of the tubing. This

> inspectioni shall be performed after the field hydrostatic test and prior to initial POWEA OPEAATION using the equipment and techniques espected to be used 1 '

during subsegaent inservice inspections.

11. P Distance is the distance of the espanded portion of l a tube which provides a sufficient length of undegraded tube expansion to resist pullout of the tube from the tubesheet. The P distance is equal to 1.79 inches and  ;

[ is measured down from the top of the tubesheet or the '

bottom of the roll transition, whichever is lower in j elevation.

3

12. P Tube is a tube .

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' a) with degradation equal to or greater than tot below I N- the P distance, and b) which has no indication of l

imperfections greater than or equal to 20% of nominal wall thickness within the P distance, and c) that 1

4 remains inservice.

i ff .lf. Tube Eirpansion is that portion of a tube which has been increased in diameter by a rolling process such that no i

crevice exists between the outside diameter of the tube

{ and the hole is the tubesheet.

i M5 j6 M Tube support Plate Pluesine Limit is used for the i disposition of a steam generator tube for continued Tb service that is emperiencing outside diameter stress

' corrosion cracking confined within the thickness of the tube support plates. These criteria are applicable for AO1 the Eleventh Operating cycle only. At tube support plate intersections, the repair limit is based on b6 maintaiaias steam generator tube serviceability as f d described below:

a. Degradation attributed to outside diameter stress l
corrosten cracking withia the bounds of the tube support plate with bobbia voltage less than or 4

equal to 2.0 volts will be allowed to remain in service.

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b. Degradation attributed te outside diameter stress corrosies cracking within the bounds of the tube l

support plate with a babbia voltage greater thaa 2.0 volts will be repaired or plugged except as j noted is 4.4.6.4.a.14.c below.

FAALEY-UNIT 2 3/4 4-12b AMENDMENT NO. 105

/g L crib h b [ub fE l'

"- ff 0" 7 -

    1. pr.A: TOR 0:0*.

. ANT sysTD4 3URVEIL* NICE REQUIRD4DIT5 (Continued)

% c. Indications of potential degradation attributed to outside diameter stress corrosion cracking within the bounds of the tube support plate with a bobbin voltage greater than 2.0 volts but less y than or equal to S.6 volts may remain in service  !

if a rotating pancake coil inspection does not detect degradation. Indications of outside '

diameter stress corrosion cracking degradation  !

with a Bobbin voltage greater than S.6 volts will

.. be plugged or repaired.

b. The steam generator shall be deterinined OPERABLE af ter completing the corresponding actions (plug or repair of all tubes exceeding the plugging or repair limit) required by Table 4.4-2.

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i rami n -owrr 2 2/4 4-12 mammer no. m u

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, 7E.A:702 00CLANT SYSTD4

  • 3 SURVEIL. *.ANCE REQUIPDtENTS (Continued) 4.4.6.5 Reports

/l,

! a.

! Following each inservice inspection of steam generator tubes,

- the number of tubes plugged, repaired or designated T* in f

  • each steam generator shall be reported to the Cossaission within 15 days of the completion of the inspection, plugging

] or repair effort.

b.

j

.The complete results of the steam generator tube and sleeve i

inservice inspection shall be submitted to the commission in a special Report pursuant to specification 6.9.2 within 12 months following the completion of the inspection. This

special Report shall include

a

1. Number and extent of tubes and sleeves inspected.

a i

2. Location and percent of well-thickness penetration for j each indication of an imperfection.

4

3. Identification of tubes plugged or repaired.

4 4'

c. Results of steam generator tube inspections which fall inte i'

Category C-3 shall be considered a REPORTABLE EVENT and shall he reported pursuant to 10CFRSO.73 prior to resumption of j

plant operation. The writtaa report shall provide a j

description of investigations conducted to determine the i cause of the tube degradation and corrective seasures takaa -

to prevent recurrence.

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d. For implementation of the voltage-based repair criteria to tube support plate intersections, notify the' staff prior to returning the steam generater to service (Mode 4) should any of the following conditions arises

~i

' 1. If estimated leakage based on tho' actual end-of-cycle i

voltage distributies would have eaceeded the leak limit

(for the postulated main steam line break utilising i licensing basis assumptions) during the previous operettag cycle.

a

2. If circumferential crack-like indications are detected ii at the tube support plate intersections.

i 3. If indications are identified that estead beyond the

confines of the tube support plate.

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. 4. If the calculated conditional burst probability exceeds 1 a 10-a, notify the NBC and provide as assessment of 1 the safety signia.aae. .f t=e ee-,,es .

  1. FAALEY-UNIT M ak,lc 2 h yp/. 43/4% 4-13a qpA//m/g~.

. No. 106 i

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.. REACTOR C00LANT SYSTEM .

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8ASES

a. Mechanical i
1. Indications of degradation in the entire length of the sleeve

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must be evaluated against the sleeve plugging limit.

2. Indication of tube degradation of any type including a
complete guillotine break in the tube between the bottom of the upper joint and the top of the lower roll expansion does not require that the tube be removed from service.

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3. The tube plugging limit continues to apply to the portion of the tube in the entire upper joint region and in the lower roll expansion. As noted above, the sleeve plugging limit applies to these areas also.
4. The tube plugging limit continues to apply to that portion of j

the tube above the top of the upper joint.

i j b. Laser Welded

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1. Indications of degradation in the length of the sleeve between the limit. weld joints must be evaluated against the sleeve plugging l ,
2. Indication of tube degradation of any type including a

! complete break in the tube between the upper weld joint and the ,

lower weld joint does not require that the tube be removed from

} service.

! 3.

At the weld joint, degradation must be evaluated in both the sleeve and tube.

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' 4. In a joint with more than one weld, the weld closest to the end of the sleeve represents the joint to be inspected and the limit of the sleeve inspection.

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5. The tube plugging limit continues to apply to the portion of

, h [ .b. the tube above the upper weld joint and below the lower weld

' joint.

! (tiedf9M)

F* tubes do not have to be plugged or repaired provided the remainder of the l

tube within the tubesheet that is above the F* distance is not degraded. The F*

distance is equal to 1.79 inches and is measured down from the top of the tubesheet or the bottom of the roll transition, whichever is lower in elevation.

included in this distance is an allowance of 0.25 inch for eddy current i' 1elevationmeasurementuncertainty.

@s b fSteam generator tube inspections of operating plants have demonstrated the

( capabi'ity to reliably detect wastage type degradation that has penetrated 205 lQ c . of the original tube wall thickness.

4 l FARLEY-UNIT 2 B3/4 4-3a

! AMDEMENT NO. 94 i

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"__-_____,________ZL_._ -, , , . . , , , _m.,

REACTOR COOLANT SYSTEM

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. BASES 1

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N 9T-~

Whenever the results of any steam generator tubing inservice inspection fall into Category C-3, these results will be reported to the Commission pursuant to s/ 10 CFR 50.73 prior to resumption of plant operation. Such cases will be i considered by the Commission on a case-by-case basis and may result in a i requirement for analysis, laboratory examinations, tests, additional eddy-current inspection, and revision to the Technical specifications, if necessary.

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FARLEY-UN!i 2 B3/4 4-3b AMEN 0 MENT N0. 94 4

o 4 =

, Insert A If the above criteria cannot be met, then the L* tube criteria may be applied or the tube must be plugged or repaired.

13. L* Length,,is the length of the expanded portion of the tube into the tube sheet from the bottom of the ro?. led transition or the top of the tube sheet, which ever is lower, that has been determined to be 1.45 inches.
14. L* Tubee , a) is a tube with degradation equal or greater than 40% below the L* 1ength and not degraded within the L* lengths b) the eddy current indication of degradation below the L*

length must be determined to be the result of cracks with an orientation no greater than 15 degrees from axial; c) the L*

criteria shall be limited to a maximum of 600 tube ends per steam generator; d) tubes qualifying as F* tubes are not classified as L* tubes; e) a minimum of 3.1 inches of the tube into the tubesheet from the top of tubesheet or bottom of the rolled transition, which ever is lower, shall be inspected using rotating pancake coil eddy current technique or an inspection method shown to give equivalent or better information on the orientation and length of axial cracks; f) a minimum aggregate of 2.07 inches of sound roll expansion; g) a maximum crack length of .39 inches; h) a maximum of 5 distinct indications with a single band of tube degradation; and 1) that remains in service.

Insert B L* is similar to F*; however, bands of axial degradation are allowed as long as sufficient non-degraded tubing is available to ensure structural and leakage integrity. L* criterion is only applicable for Unit 2 Cycle 11.

Provided below is the Unit 2 cycle 11 specific L* criterion:

Unit 2 Cycle 1i Specific L* Criterion Parameter Value Minimum distance of SRE 2.07 inches Maximum number of distinct degradation areas in a band 5 Maximum inclination angle within a single band 15 degrees Maximum crack length .39 inches Minimum distance of SRE from the bottom of the transition 1.45 inches roll to the top of the indication

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