ML20148P717

Proposed Tech Specs Revising Wording to Support Installation of Tube Sleeves as Alternative to Plugging to Repair Defective SG Tubes

ML20148P717
Person / Time
Site:	Calvert Cliffs
Issue date:	06/27/1997
From:	BALTIMORE GAS & ELECTRIC CO.
To:
Shared Package
ML20141F534	List: ML20141F530 ML20148P717
References
NUDOCS 9707030034
Download: ML20148P717 (15)

Text

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j 3/4.4 REACTOR C00UWIT SYSTEM 3/4.4.5 STEAM GENERATORS

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i LIMITING CONDITION FOR OPERATION i

3.4.5 Each steam generator shall be OPERABLE.

j APPLICABILITY: MODES 1, 2, 3 and 4.

j ACTION: With one or more steam generators inoperable, restore the i

4 inoperable generator (s) to OPERABLE status prior to increasing T., above 200*F.

i i

j SURVEILLANCE REQUIREMENTS i

4.4.5.0 Each steam generator shall be demonstrated OPERABLE by perfomance

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of the following augmented inservice inspection program and the requirements of Specification 4.0.5.

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4.4.5.1 St+am Generator Samole Se' ec':fon und Inspection - Each steam.

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generator small be detem' ned OPERnBLB dur' ng shutdown by selecting and i

inspecting at least the minimum number of steam generators specified in Table 4.4-1.

j 4.4.5.2 Steam Gonorator Tube Samole Select' on and Ensooction - The steam generator tube m' n' mum sample s' re, inspect' on resu' t c' assification, and the corresponding action required shall be as specified in Tablead A-h i

The inservice inspection of steam generator tubes shall be perfomed at the frequencies specified in Specification 4.4.5.3 and the inspected ~ tubes j

shall be verified acceptable per the acceptance criteria of

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Specification 4.4.5.4.

When applying the exceptions of 4.4.5.2.a through i

4.4.5.2.c. previous defects or imperfections in the area repaired by 1

i sleeving are not considered an area requiring reinspection. The tubes

[

selected for each inservice inspection shall include at least 3% of the total number of tubes in all steam generators; the tubes selected for these j

inspections shall be selected on a random basis except:

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

indicates critical areas to be. inspected, then at least 50% of j

the tubes inspected shall be from these critical areas.

b.

The first inservice inspection (subsequent to the preservice inspection) of each steam generator shall include:

i 1.

All nonplugged tubes that previously had detectable wall l

penetrations (> 20%), and 5-i i

4 i

i CALVERT CLIFFS - UNIT 1 3/4 4-10 Amendment No. 213 i

j 9707030034 970627 e

PDR ADOCK 05000317

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l 3/4.4 REACTOR C00UUli SYSTEM l

SURVEILLANCE REQUIREMENTS (Continued) m i

outage ~if the results of the two previous inspections were not in the C-3 Category. However, if the results of either of the 1

previous two inspections were in the C-2 Category, an engineering i

assessment shall be performed before operation beyond 24 months l

and shall provide assurance that all tubes will retain adequate j

)

structural margins against burst throughout nomal operating, j

transient, and accident conditions until the end of the fuel cycle or 30 months, whichever occurs first. 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 l

demonstrate that previously observed degradation has not continued and no' additional degradation has occurred.

i theinspection interval may be extended to a maximum of once per 40 months.

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b.

If the inservice insp ection 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 i

j least.once per 20 months. The increase in inspection frequency shall apply until the subsequent inspections satisfy the criteria i

of Specification 4.4.5.3.a; the interval may then be extended to l-a maximum of once per 30 or nths, as applicable.

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c.

Additional, unscheduled ins ce inspections shall be perfomed on each steam generator in a ordance with the first sample t

i inspection specified in Tabl 4.4-2 durino the shutdown M p. F 3 l

subsequent to any of the following conditions:

h t

l 1.

Primary-to-secondary tube leaks (not including leaks originating from tube-to-tube sheet welds) in excess of the l'

limits of Specification 3.4.6.2, i

2.

A' seismic occurrence greater than the Operating Basis Earthquake.

3.

A loss-of-coolant accident requiring actuation of the engineered safeguards, or 4.

A main steam line or feedwater line break.

d.

The provisions of Specification 4.0.2 do not apply for extending i

the frequency for perfoming inservice inspections as specified in Specifications 4.4.5.3.a and b.

F CALVERT CLIFFS - UNIT 1 3/4 4-12 Amendment No. 188 l

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3/4.4 _ REACTOR COOLANT SYSTEM I

SURVEILLANCE REQUIREMENTS (Continued) 4.4.5.4 Acceptance Criteria a.

As used in this Specification:

1.

Tubino or Tube neans 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 l

contour of a tube from that required by fabrication drawings or specifications.

Eddy-current testin 20% of the nominal tube wall thickness,g indications below if detectable, may be considered as imperfections.

3.

Deoradation means a service-induced cracking, wastage, wear l

or general corrosion occurring on either inside or outside of a tube.

4.

Decraded Tube means a tube containing imperfections > 20% of l

the nominal wall thickness caused by degradation.

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5.

% Deoradation means the percentage of the tube wall thickness I

affected or removed by degradation.

6.

Defect means an imperfection of such severity that it exceeds

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the plugging or repair limit. A tube containing a defect is defective. Any tube which does not pemit the passage of the eddy-current inspection probe shall be deemed a defective tube.

7.

Pluccino or Repair Limit means the imperfection depth at or beyond which the tube shall be removed from service by plugging, or repaired by sleeving in the affected area 1

because it may become unserviceable prior to the next inspection. The plugging or repair limit imperfection depths are specified in percentage of nominal wall thickness as follows:

a.

origi nal tube wal l................................ 40%

l b.

Westinghouse laser wd ded sleeve wall............. 40%

l 8.

Unserviceable describes the condition of a tube if it leaks I

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 4.4.5.3.c, above.

9.

Tu_be 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.

CALVERT CLIFFS - UNIT 1 3/4 4-13 Amendment No. 213 i

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t 3/4.4 REACTOR C0OLANT SYSTEN SURVEILLANCE REQUIREMENTS (Continued)

10. Tube Repair _ refers to a process that reestablishes tube serviceability. Acceptabl tube repairs will be perfomed by the following proces :

pg Westinghouse Laser Welded Sleeving as described in the a) proprietary Westinghouse Reports WCAP-13698~, Revision 2

" Laser Welded Sleeves for 3/4 Inch Diameter Tube Feedring-Type and Westinghouse Preheater Steam Generators, Generic Sleeving Report," April 1995; and WCAP-14469, " Specific Application of Laser Welded Sleeving for the Calvert Cliffs Power Plant Steam Generators," November 1995.

Tube repair includes the removal of plugs that were W

previously installed as a corrective or preventive measure.

' A tube inspection per Specification 4.4.5.4.a.9.is required prior to returning previously plugged tubes to service.

The steam generator shall be detemined OPERABLE after completing u.

the corresponding actions (plug or repair all tubes exceeding the plugging or repair limit and all tubes containing through-wall l

cracks) required by Tabl 4.4-2 j

O 44

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4.4.5.5 Reports Following each inservice inspection of stera generator tubes, the number of tubes )1ugged or repaired in each steam generator shall a.

be reported to tie Comission within 15 days pursuant to l

10 CFR 50.4.

The complete results of the steam generator tube inservice b.

inspection during the report period shall be submitted to the Comission prior to March 1 of each year pursuant to 10 CFR 50.4.

This report shall include:

1.

Number and extent of tubes inspected.

2.

Location and percent of wall-thickness penetration for each indication of an imperfection.

3.

Identification of tubes plugged or repaired.

Results of steam generator tube inspections which fall into c.

Category C-3 require verbal notification of the NRC Regional Administrator by telephone within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to resumption of plant geration. The written followup of this report shall provide a description of investigations conducted to determine cause of the tube degradation and corrective measures taken to prevent recurrence and shall be submitted within the next 30 days pursuant to 10 CFR 50.4.

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~~CA TNT-CLIFFS - UNIT-1

--3/4-4 --- --Amendment-No.-216---

= _ _

TABLE 4.4-3

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STEAM GENERATOR REPAIRED TUBE INSPECTION IST SAMPLE INSPECTION 2ND SAMPLE INSPECTION Sample Size Result Action Required Result Action Required A minimum of 20% of C-1 None NA NA repaired tubes (l)(2)

C-2 Plug Defective repaired tubes and C-1 None inspect 100% of the repaired tubes in this SG.

C-2 Plug defective repaired tubes I

C-3 Perform action for C-3 result of first sample C-3 Inspect all repaired tubes in this Other SG is C-1 None SG plug defective tubes and inspect 20% of the repaired tubes in the other SG.

24-hour verbal notification to Other SG is C-2 Perform action for C-2 result of NRC with written follow-up, first sampic l

pursuant 10 CFR 50.4.

Other SG is C-3 Inspect all sepaired tubes in each SG and plug defective tubes.

24-hour verbal notification to NRC with written follow-up, pursuant 10 CFR 50.4.

(1) Er.ch repair method is considered a separate population for determination of scope expansion.

(2) 'Ihe inspection of repaired tubes may be performed on tubes from either SG based on outage plans.

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3/4.4 REACTOR COOLANT SYSTEM BASES adequate structural margins against burst during all nomal operating, transient, and accident conditions until the end of the fuel cycle. This evaluation would include the following elements:

1.

An assessment of the flaws found during the previous inspections.

2.

An assessment of the structural margins relative to the criteria of Regulatory Guide 1.121 " Bases for Plugging Degraded PWR Steam Generator Tubes," that can be expected before the end of the fuel cycle or 30 months, whichever comes first.

.h 3.

An update of the assessment model, as appropriate, based on j

Q comparison of the predicted results of the steam generator tube q

integrity assessment with actual inspection results from previous j

inspections.

N The plant is expected to be operated in a manner such that the' secondary coolant will be maintained within those chemistry limits found to result in L

negligible corrosion of the steam generator tubes.

If the secondary

(

coolant chemistry is not maintained within these limits, localized A

corrosion may likely result in stress corrosion cracking. The extent of I

cracking during plant operation would be Ifmited by the limitation of steam

)j h generator tube leakage between the Primary Coolant System and the Secondary Coolant System (primary-to-secondary leakage = 1 gallon er minute, total).

Cracks having a primary-to-secondary leakage less than t is limit during operation will have an adequate margin of safety to withstand the loads i

imposed during nonnal operation and by postulated accioents. Operating

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plants have demonstrated that primary-to-secondary leakage of I gallon

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j g perminute can readily be detected by radiation monitors of steam generator blowdown.

Leakage in excess of this limit will require plant shutdown and j(

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an unscheduled inspection, during which the leaking tubes will be located k

i and plugged or repaired. Defective tubes may be repaired by a Westinghouse I

Laser Welded Sleeve The technical bases for Westinghouse Laser Welded l

Sleeve are described in the proprietary Westinghouse Reports WCAP-13698, Revision 2 " Laser Welded Sleeves for 3/4 Inch Diameter Tube Feedring-Type I

and Westinghouse Preheater Steam Generators, Generic Sleeving Report,"

April 1995; and WCAP-14469, " Specific Application of Laser Welded Sleev l

for the Calvert Cliffs Power Plant Steam Generators," November 1995.

l Wastage-type defects are unlikely with proper chemistry treatment of the secondary coolant. However, even if a defect should develop in service, it will be found during scheduled inservice steam generator tube examinations.

Plugging or repair will be required for all tubes with imperfections at or exceeding the plugging or repair limit of 40% of the original tube nominal wall thickness.

If a tube contains a Westinghouse Laser Welded Sleeve with imperfection exceeding 40% of nominal wall thickness it must be plugged.

The basis for the sleeve plugging limit is based on E,egulatory Guide 1.121 analyses, and is described in the Westinghous sleet ing technical report 5

1 mentioned above." Steam generator tube inspe ions < lf operating plants hay l

demonstrated th capability to reliabl de et degr idation that has A

M6-4 nh 1

E i ;,-ay CALVERT CLIFFS - UNIT 1 B 3/4 4-4 Amendment No. 213

i i

Insert A:

c.

ABB-Combustion Engineering Leak Tight Sleeve wall........ 28%

Insert B:

b.

ABB-Combustion Engineering Leak Tight Sleeving as described in the t

proprietary ABB-Combustion Engineering Report CEN-630-P, Revision i

01,' " Repair of 3/4" O.D.' Steam Generator Tubes Using Leak Tight i

l l

Sleeves," August 1996. A post-weld heat treatment during installation will L

i be performed.

l Insert C:

' The technical bases for the Combustion Engineering Leak Tight Sleeve are l

described in the proprietary ABB-Combustion Engineering Report CEN-630-P, Revision 01, " Repair of 3/4" O.D. Steam Generator Tubes Using Leak Tight L

Sleeves," August 1996 l

[

i-Insert D:

or an ABB-Combustion Engineering Leak Tight Sleeve exceeding 28%

i Insert E:

(Note: the sleeve plugging limit also includes 20% combined allowance for eddy -

current uncertainty and additional degradation growth.)

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ATTACHMENT (2) i 1

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UNIT 2 MARKED-UP TECHNICAL SPECIFICATION PAGES REVISED PAGES:

3/4 4-10 3/4 4-12 3/4 4-13 3/4 4-14 B 3/4 4-4 Baltimore Gas & Electric Company Docket Nos. 50-317 and 50-318 June 27,1997

l+

3/4.4 REACTOR COOLANT SYSTEM l

l 3/4.4.5 STEAM GENERATORS j.

LIMITING CONDITION FOR OPERATION I

3.4.5 Each steam generator shall be OPERABLE.

l APPLICABILITY: MODES 1, 2, 3 and 4.

ACTION: With one or more steam generators inoperable, restore the j

i inoperable generator (s) to OPERABLE status prior to increasing T.,, above 200 F.

}

j i

I j.

SURVEILLANCE REQUIREMENTS I

4.4.5.0 Each steam generator shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the i

j requirements of Specification 4.0.5.

l i

4.4.5.1 Steam Generator Sample Selection and Inspection - Each steam i 4. h Y

i generator shall be determined 0PERABLE dur' ng shutdown by selecting and inspecting at least the minimum number of steam generators specified in i

Table 4.4-1.

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I 4.4.5.2 Steim Generator Tube Sample Selection and Enspection - The steam j

generator tuae minimum sample size, inspection resu' t classification, an the corresponding action required shall be.as specified in Tablei4.4-2.

i i

The inservice inspection of steam generator tubes shall be perfonned at t e frequencies specified in Specification 4.4.5.3 and the inspected tubes s

shall be verified acceptable per the acceptance criteria of i

i Specification 4.4.5.4.

When applying the exceptions of 4.4.5.2.a through t

I 4.4.5.2.c previous defects or imperfections in the area repaired by i

sleeving are not considered an area requiring reinspection. The tubes

[

selected for each inservice inspection shall include at least 3% of the

]

J r

total number of tubes in all steam generators; the tubes selected for these i

inspections shall be' selected on a random basis except:

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.

l b.

The first intervice inspection (subsequent to the preservice inspection) of each steam generator shall include:

1.

All nonplugged tubes that previously had detectable wall penetrations (>20%), and

.CALVERT CLIFFS - UNIT 2 3/4 4-10 Amendment No. 190

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-i 4

i

.l' 3/4.4 - RfACTOR C00LMT SISIRI

[

SURVEILLANCE REQUIREMENTS (Continued) 1 j

were not in the C-3. Category. However, if the results of either of the previous two inspections were in the C-2 Category, an engineering assessment shall be performed before operation beyond 24 months and shall provide assurance that all tubes will retain j

adequate structural margins _ against burst throughout normal operating, transient, and accident conditions until the end of the fuel cycle or 30 months, whichever occurs first.

If two consecutive inspections follt ing 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 ma e ext d o a maximum of once per 40 j

months.

4.p i

e b.

If the inservice insection of a steam generator conduc+ed in accordance with Table'4.4-2 at 40-month intervals fall ia.

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 inspections satisfy.the criteria 1:

of Specification 4.4.5.3.a; the interval may then be extended to j

a maximum of once per 30 mo s or 40 mr#.hs, as applicable.

]

c.

Additional, unscheduled inservice inspections shall be performed j

on each steam generator in ac cordance with the first sample j,

inspection specified in Table 4.4-2nduring the shutdown subsequent-to.any of the following conditions:

4,4 y I;

1.

Primary-to-secondary tube leaks (not including leaks l

. originating from tube-to-tube sheet welds) in excess of the-limits of Specification 3.4 6.2, i

l 2.

A seismic occurrence greater than the Operating Basis Earthquake, 3.

A loss-of-coolant accident requiring actuation of the engineered safeguards, or

?

j-4.

A main steam line or feedwater line break.

d.

The provisions of Specificatin 4.0.2 do not apply for extending the frequency for perforning inservice inspections as specified j:

in Specifications 4.4.5.3.c and b.

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l CALVERT CLIFFS - UNIT 2 3/4 4-12 Amendment No. 165 l

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3/4.4 REACTOR COOLANT SYSTEM SURVEILLANCE REQUIREMENTS (Continued) 4.4.5.4 Acceptance Criteria 3

a.

As used in this Specification:

1.

Tubino or Tube means that portion of the tube or sleeve which fonns the primary system to secondary system pressure boundary.

2.

Imperfection means an exception to the dimensions, finish or l

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 det'ectable, may be considered as imperfections.

3.

Decradation means a service-induced cracking, wastage, wear l

or general corrosion occurring on either inside or outside of i

a tube.

4.

Deoraded Tube means a tube containing imperfections > 20% of l

the nominal wall thickness caused by degradation.

5.

% Deoradation 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 or repair limit. A tube containing a defect is defective. Any tube which does not pennit the passage of the eddy-current inspection probe shall be deemed a defective tube.

4 7.

Pluccino or Repair Limit means the imperfection depth at or beyond which the tube shall be removed from service by 1

plugging, or repaired by sleeving in the affected area because it may become unserviceable prior to the next inspection. The plugging or repair limit imperfection depths are specified in percentage of nominal wall thickness as i

follows:

1 I

a.

o ri gi nal tube wal l................................ 40%

b.

Westinghouse laser welded sleeve wall............. 40%

j 8.

Unserviceable describes the condition of a tube if it leaks l

+

or contains a defect large enough to affect its structural integrity in the event of an Operating Basis Earthquake, a j

loss-of-coolant accident, or a steam line or feedwater line j

break as specified in 4.4.5.3.c, above.

9.

Tube Inspection means an inspection of the steam generator I

tube from the point of entry (hot leg side) completely around 1

the U-bend to the top support of the cold leg.

j CALVERT CLIFFS - UNIT 2 3/4 4-13 Amendment No. 190

(.

j 3/4.4 BEA_CTOR C00LANT SYSTEN SURVEILUUICE REQUIREMENTS (Continued) i

10. Tube Reoair. refers to a process that reestablishes tube

!~

serviceability. Acceptab tube repairs will be performed by i

the following process: 65 l

a) Westinghouse Laser Welded Sleeving as described in the groprietaryWestinghouseRep/4InchDiameterTubeorts WCAP-13 Laser Welded Sleeves for 3 Feedring-Type and Westinghouse Preheater Steam Generators, Generic Sleeving Report " April 1995; and j

.WCAP-14469, " Specific Application of Laser Welded Sleeving for the Calvert Cliffs Power Plant Steam 1

Generators," November 1995.

Tube repair includes the removal of plugs that'were previously installed as a corrective or preventive measure.

A tube inspection per Specification 4.4.5.4.a.9 is required prior to returning previously plugged tubes to service.

b.

The steam generator shall be determined OPERABLE after completing the corresponding actions (plug or repair all tubes exceeding the plugging or repair limit and all tubes containing through-wall cracks) required by Table 4.4 stol + +-s 4.4.5.5 Reports 5

i a.

Following each inservice inspection.of steam generator tubes, the number of tubes plugged or repaired in each steam generator shall i'

be reported to the Commission within 15 days pursuant to 10 CFR 50.4.

l 1

b.

The complete results of the steam generator tube inservice inspection during the report period shall be submitted to the Commission prior to March 1 of each year pursuant to 10 CFR 50.4.

This report shall include:

1.

Number and extent of tubes 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 require verbal notification of. the NRC Regional Administrator _ by telephone within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to resumption of plant operation. The written followup of this report shall

' provide a description of investigations conducted to determine cause of the tube degradation and corrective measures taken to prevent recurrence and shall be submitted within the next 30 days pursuant to 10 CFR 50.4.

I CALVERT CLIFFS - UNIT 2 3/4 4-14 Amendment No. 193

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TABLE 4.4-3 s

STEAM GENERATOR REPAIRED TUBE INSPECTION IST SAMPLE INSPECTION 2ND SAMPLE INSPECTION Sample Size Result Action Required Result Action Required A minimum of 20% of C-1 None NA

-NA repaired tubes (l)(2) l C-2 Plug Defective repaired tubes and C-1 None inspect 100% of the repaired tubes in this SG.

C-2 Plug defective repaired tubes C-3 Perform action for C-3 result of first sample C-3 Inspect all repaired tubes in this Other SG is C-1 None I

SG plug defective tubes and inspect 20% of the repaired tubes in the other SG.

24-hour verbal notification to Other SG is C-2 Perform action for C-2 result of NRC with written follow-up, first sample f

pursuant 10 CFR 50.4.

Other SG is C-3 Inspect all repaired tubes in each SG and plug defective tubes.

24-hour verbal notification to NRC with written follow-up, pursuant 10 CFR 50.4.

I I

(1) Each repair method is considered a separate population for determination of scope expansion.

(2) The inspection of repaired tubes may be performed on tubes from either SG based on outage plans.

lC s

.. _ _. _ _ _ _ _. _ _.. _ = _ _ _. _. _ _ _ _ _ _ _ _ _ _.

_m.__..________-__m.______.___.__

i 3/4.4 -REACTOR COOLANT SYSTEM adequate structural margins against burst during all normal operatin 4

transient, and accident conditions until the end of the fuel cycle. g,This j

evaluation would include the following elements:

1.

An assessment of the flaws found during the previous inspections.

2.

An assessment of the structural margins relative 'to the criteria of i

l Regulatory Guide 1.121, " Bases for Plugging Degraded PWR Steam l

A, Generator Tubes," that can be expected before the end of the fuel t

L

,i cycle or 30 months, whichever comes first.

lh 3.

i

(

An update of the assessment model, as ap)ropriate, based on comparison of the predicted results of tte steam generator tube 1

integrity assessment with actual inspection results from previous 1

inspections.

j The plant is expected to be operated in a manner such that the secondary

_K coolant will be maintained within those chemistry limits found to result in i

' negligible corrosion of the steam generator tubes. If the secondary i

)

coolant chemistry is not maintained within these limits, localized i

corrosion may likely result in stress corrosion cracking. The extent of J

cracking during plant operation would be limited by the limitation of steam q) generator tube leakage between the Primary Coolant System and the Secondar Coolant System (primary-to-secondary leakage = 1 gallon per minute, total)y

}l Cracks having a primary-to-secondary leakage less than this limit during t

operation will have an adequate margin of safety to withstand the loads i

j imposed during normal operation and by postulated accidents. Operating I

}

plants have demonstrated that primary-to-secondary leakage of I gallon per minute can readily be detected by radiation monitors of steam generator blowdown.

Leakage in excess of this limit will require plant shutdown and

..g i

(T an unscheduled inspection, during which the leaking tubes will be located

)

and plugged or repaired. Defective tubes may be repaired by a Westinghouse 1

y(

Laser Welded Sleeve The technical bases for Westinghouse Laser Welded sleeve are descrLbed in the proprietary Westinghouse Reports WCAP-13698, N

Revision 2, " Laser Welded Sleeves for 3/4 Inch Diameter Tube Feedring-Type and Westinghouse Preheater Steam Generators, Generic Sleeving Report "

April 1995; and WCAP-14469, " Specific App 1tcation of Laser Welded Sleevi for the Calvert Cliffs Power Plant Steam Generators," November 1995.

i

g i

Wastage-type defects are unlikely with proper chemistry treatment of the i

secondary coolant. However, even if a defect should Melop in service, it.

will be found during scheduled inservice steam generator tube examinations.

Plugging or repair will be required for all tubes with imperfections at or -

exceeding the plugging or repair limit of 40% of the tube original nominal wall thickness.- If a tube contains a Westinghouse Laser Welded Sleeve with imperfection exceeding 40% nominal wall thickness it must be plugged. The basis for the sleeve plugging limit is based on gulatory Guide 1.121 analyses, and is described in the Westinghouse /si eving technical report J mentioned above. Steam generator tube inspec fion of operating plants have demonstrated the capabil ty_tn reliably dele. de adation that has 5

& A}ld-6sekUNere id$

Q CALVERT CLIF S - UNIT 2 B 3/4 4-4 Amendment No. 190 i

. m l

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l Insert A:

c.

ABB-Combustion Engineering Leak Tight Sleeve wall........ 28%

l Insent B:

b.

ABB-Combustion Engineering Leak Tight Sleeving as described in the proprietary ABB-Combustion Engineering Report CEN-630-P, Revision 01, " Repair of 3/4" O.D. Steam Generator Tubes Using Leak Tight Sleeves," August 1996. A post-weld heat treatment during installation will '

be performed.

Insert C:

The technical bases for the Combustion Engineering Leak Tight Sleeve are described in the proprietary ABB-Combustion Engineering Report CEN-630-P,

)

Revision 01, " Repair of 3/4" O.D. Steam Generator Tubes Using Leak Tight Sleeves," August 1996 Insert D:

or an ABB-Combustion Engineering Leak Tight Sleeve exceeding 28%

l Insert E:

(Note: the sleeve plugging limit also includes 20% combined allowance for eddy current uncertainty and additional degradation growth.)

1 i

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1

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Insert-A:

c.

ABB-Combustion Engineering Leak Tight Sleeve wall........ 28%

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Insert B:

b.

ABB-Combustion Engineering Leak Tight Sleeving as described in the proprietary ABB-Combustion Engineering Report CEN-630-P, Revision 01, " Repair' of 3/4" O.D. Steam Generator Tubes Using Leak Tight i

Sleeves," August 1996. A post-weld heat treatment during installation will j

be performed.

Insert C:

The technical bases for the Combustion Engineering Leak Tight Sleeve are described in the proprietary ABB-Combustion Engineering Report CEN-630-P, Revision 01, " Repair of 3/4" O.D. Steam Generator Tubes Using Leak Tight i

Sleeves," August 1996 l

Insert D:

or an ABB-Combustion Engineering Leak Tight Sleeve exceeding 28%

l Insert E:

(Note: the sleeve plugging limit also includes 20% combined allowance for eddy

.i current uncertainty and additional degradation growth.)

j l

L l

l 4

(L.

J