ML17311A823

Proposed Tech Specs Section 3/4.4.4 Re Sleeving Process for SG Tube Repair

ML17311A823
Person / Time
Site:	Palo Verde
Issue date:	04/18/1995
From:	ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:
Shared Package
ML17311A821	List: ML17311A823
References
NUDOCS 9504270149
Download: ML17311A823 (32)

Text

R INFORMATION ONL REACTOR COOLANT SYSTEM SURVEILLANCE RE UIREMENTS (Continued) 4.4.4.4 Acce tance Criteria

a. As us ecif ication a.a. cnsc.r 4 pe t2.

z4 contour of a tube from that required by fabrication drawings or specifications. Eddy-current testing indications below 20K of the nominal tube wall thickness, if detectable, may be considered as imperfections.

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

than or equal to 20K of the nominal wall thickness caused by degradation.

%~i affected or removed by degradation.

I s

ot r a pa.ic Defect means/an

' imperfection of such

't.

severity that it exceeds th u A tube containing a defect is defective.

Sea. in eel 4 Pdm-qa.

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 4.4;4 3c., above.

~Tt from the point of entry (hot leg side) completely around the U-bend to the top support of the cold leg.

Preservice Ins ection 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 Sc tL ines.< r pet.cp PALO VERDE - UNIT 1 3I4 4-14 9504270i 49 'SO .

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INSERTS TO PAGE 3/4 4-14 system pressure boundary.

Plu in or Re air 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. The plugging or repair imperfection depths are specified in percentage of nominal wall thickness as follows:

a. Original tube wall 40%

b. ABB-CE Leak Tight Sleeves 35%

it, ~Tube Re air refers to welded cleaving as described in ABB Combustion Engineering Rcport CEN-dig-p "Palo Verde Units 1, 2, and 3 Steam Generator Tube Repair using Leak Tight Sleeves" Rev 01 dated January 1995 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 preventative measure. A tube inspection per Specification 4.4.4.4.a.9 is required prior to returning previously plugged tubes to service.

I~

lR INFORMATlON ONL REACTOR..COOLANT. SYSTEM SURVEILLANCE RE UIREMENTS Continued) condition of the tubing. This inspection was performed prior to the field hydrostatic test and prior to initial POWER OPERATION using the..equipmgnt and techniques expected'o be used during subsequent inservice inspections.

oc mph.ic'he steam generator shall be determined OPERABLE after completing the corresponding actions (plugall tubes exceeding the plugging<or <<~<<

limit and all tubes containing through-wall cracks) required by Table 4,4>>2. c ~p~c.'ri~p- 'r~~~~ ~~y 4~ ~~q~i~h 'i~ ~~~~he ~~ ~db

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4& CD&(SAC QL % 4&&It Within 15 days following the completion of each inservice inspection of steam generator tubes, the number of tubes plugged in each steam generator shall be reported to the Commission in a Special Report pursuant to Specification 6.9.2. ~Dr Co Pn.wax.g

b. The complete results of the steam generator tube inservice inspection shall be submitted to the Commission in a Special Report pursuant to Specification 6.9.2 within 12 months following completion of the inspection. This Special 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<os c~pc <<c-@-

C. Results of steam generator tube inspections which fall into Category C-3 shall be reported in a Special Report to the Commission pursuant to Specification 6.9.2 within 30 days and prior to resumption of plant operation and shall provide a description of investigations conducted to determine cause of the tube degradation and corrective measures taken to prevent recurrence.

PALO VEROE " UNIT 1 3/4 4-15

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TABLE 4.4-2 STEAM GENERATOR TUBE INSPECTION 1ST SAMPLE INSPECTION 2ND SAMPLE INSPECTION 3RD SAMPLE INSPECTION Sample Size Result Action Required Result Action Required Result Action Required A minimum of C-1 None N. A. N. A. N. A. N. A.

S Tubes per g c~,~bc S. G.

C-2 p oc Wps.wr C-1 None Plugdefective tubes N, A. N. A.

and inspect additional Plug defective tiibes C-1 or rwpa.ir None 2S tubes in this S. G. C-2 and inspect addiiiunal C-2 Plug defective tubes 4S tubes in this S G Perform action for C-3 C-3 result of first sample Perform action for C-3 C-3 result of first N. A. N. A.

sample C-3 Inspect all tube in All other this S. G., plug~ e. S. G.s are None N.A, N. A.

fective tubes and C-I inspect 2S tubes in Some S Gs Perform action for each other S. G. N. A.

C-2 but no C-2 result uf a<cond additional sample Notification to NRC S. G. are pursuant to f50.72 C-3 (b)(2) of 10CFR Additional Inspect all tubes in ec'c.Qir Part 50 S. G. is C-3 each S. G. and plug defective tubes.

Notification to NRC N. A.

pursuant to $ 50.72 (b)(2) of 10 CF R Part 50

+Iiere N is the number of steam, generators in the unit, and n is the number of steam generators inspected

-3 N during an inspection

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REACTOR COOLANT SYSTEt'1 BASES 3/4.4.4 STEAN GENERATORS The surveillance requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the RCS will be main-tained. 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 maintain 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 Qf characterizing the nature and cause of any tube degradation so that corrective measures can be taken.

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 negligible corrosion of the steam generator tubes. If the secondary coolant chemistry is not maintained within these limits, localized corrosion may likely result in stress corrosion cracking. The extent of cracking during plant opera-tion would be limited by the limitation of steam generator tube leakage between the primary coolant system and the secondary coolant system (primary-to-secondary leakage = 0. 5 gpm per steam generator). Cracks having a primary-to-secondary leakage less than this limit during operation will have an adequate margin of safety to withstand the loads imposed during normal operation and by postulated accidents. Operating plants have demonstrated that primary-to-secondary leakage of 0.5 gpm per steam generator can readily be detected by radiation monitors of steam generator blowdown. Leakage in excess of this limit will, require plant shutdown and an unscheduled inspection, during which the leaking tubes will be located and plugged. c r c ohio.'i~c-h-Wastage-type defects are unlikely with proper chemistry treatment of the secondary coolant. However, even if d defect should develop arnein service, it will be found during scheduled inservice steam generator tube examinations. Plugging~vv re.gc 'v.

will be required for all tubes with imPerfections exceeding the Plugging~limit mr re.f~;s-of qOX of the tube nominal wall thicknes Steam generator tube inspections of operating plants have demonstrated the capability to reliably detect degradat'ion that has penetrated 20".0 of the original tube wall thickness. (<~~~~4 R)

C e>'qi'~ < gg/ a J.'~ e.he,-c.sm 4sLag Q~++ 5~a. ~tgt i~X ma.<N Whenever the results of any steam generator tubing inservice inspection fall into Category C-P, these results will be promptly reported to the Commis- (a~sees, S) sion pursuant to Specification 6.9.1 prior to the resumption cf 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 of the Technical Specifications, if necessary.

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PALO VERDE UNIT 1 B 3/4 4-3

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R iNFORMATlON QNL REACTOR COOLANT SYSTEM SURVEILLANCE REOUI'REMENTS Continued) 4.4.4.4 Acceptance Criteria

a. As S ecification L. c.c. tnscr pc c, 2 i,.

contour of a tube from that required by fabrication drawings or specifications. Eddy-current testing indications below 20'f the nominal tube wall thickness, if detectable, ling may be considered as imperfections.

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

~DT than or equal to 20K of the nominal wall thickness caused by degradation.

~ Dearadation means the percentage of the tube wall thickness affected or removed by degradation.

or c'ape.'6 Oefect means an imperfection of such severity that it exceeds t in .limit. A tube containing a defect is defective.

Sac t~sc rW p'a.qa 8V,. 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 4.4.4.3c., above.

9 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.

io,g. 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 ll. Sa.tL WWaa e4 gem p

PALO VERDE - UNIT 2 3/4 4-14

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INSERTS TO PAGE 3/4 4-14 system pressure boundary.

a Plu in or Re air 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. The plugging or repair imperfection depths are specified in percentage of nominal wall thickness as follows:

a. Original tube wall 40%

b. ABB-CE Leak Tight Sleeves 35%

i l. ~Tube Re air refers to welded sleeving as described in ABB Combustion Engineering Report CEN-613-P "Palo Verde Units 1, 2, and 3 Steam Generator Tube Repair using Leak Tight Sleeves" Rev 01 dated January 1995 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 preventative measure. A tube inspection per Specification 4.4.4.4.a.9 is required prior to returning previously plugged tubes to service.

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fR INFORMATION ONL)

REACTOR COOLANT SYSTEM SURVEILLANCE RE UIREMENTS (Continued) condition of the tubing. This inspection was performed prior to the field hydrostatic test and prior to initial POWER OPERATION using the equipment and techniques expected to be used during subsequent inservice inspections.

or C'a.q~r

b. The steam generator shall be d termined OPERABLE after completing the corresponding actions (plug<all tubes exceeding the plugging<oc r~pc6a limit and all tubes containing through-wall cracks) required by Table 4.4-2. Dqfacki~a %t W~s me 4c. ~cpa ice.h t~a~~b~~c.~~'t9

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ms e e Ra.V. Ol ha~4 Ya~egt~Se seseess tssi~~s ss 4a~'q~sr Within 15 days following the completion of each inservice inspection of steam generator tubes, the number of tubes plugged in each steam generator shall be reported to the Commission in a Special Report pursuant to Specification 6.9.2. o~ v'a qa.'i<a.h, The complete results of the steam generator tube inservice inspection shall be submitted to the Commission in a Special Report pursuant to Specification 6. 9. 2 within 12 months following completion of the inspection. This Special 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<ac ca.qai~a.4.

C. Results of steam generator tube inspections which fall into Category C-3 shall be reported in a Special Report to the Commission pursuant to Specification 6.9.2 within 30 days and prior to resumption of plant operation and shall provide a description of investigations conducted to determine cause of the tube degradation and corrective measures taken to prevent recurrence.

PALO VERDE - UNIT 2 3/4 4-15

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TABLE 4.4-2 STEN GENERATOR TUBE INSPECTION 1ST SAMPLE INSPECTION 2ND SAMPLE INSPECTION 3RD SAMPLE INSPECTION Sample Size Result Action Required Result Action Required Result Action Required A minimum'of C-1 None N. A. N. A. N. A. N. A.

S Tubes per OCC.+j,~

S. G.

C-2 P~lug defective tubes ffqgo"W None N. A. N. A.

and inspect additional Plugdefective tubes C-1 None 2S tubes in this S. G. C-2 and inspect additional C-2 . Plug elective tubes 4S tubes ln this-S. G.

Perform action for C-3 C-3 result of first sample .

Perform action for

~r Sa gMAC C-3 C-3 result of first N. A. N. A.

sample C-3 Inspect all tubes in All other this S. G., plugde- S. G.s are None N. A. N. A.

fective tubes and C-1 inspect 2S tubes ln Some S. G.s Perform action for each other S. G. N. A. N. A.

C-2 but,no C-2 result ot second additional sample Notification to NRC S. G, are pursuant to f50.72 C-3 (b)(2) of 10 CFR Additional Inspect all tubes in Of Wyatt<

Part 50 S. G. Is C-3 each S. G..and plug<

defective tubes.

Notification to NRC N. A. N. A.

pursuant to $ 50.72 (b)(2) of 10CFR Part 5Q is the number

~here N is the number of steam gsnerators in the unit, and n of steam generators inspected during an inspection

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REACTOR COOLANT SYSTEM BASES 3/4.4.4 STEAM GENERATORS The surveillance requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the RCS will be main-tained. The program for inservice inspection of steam generator tubes is based

'fon a modification of Regulatory Guide 1. 83, Revision l. Inservice inspection steam generator tubing is essential in order to maintain 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.

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 negligible corrosion of the steam generator tubes. If the secondary coolant chemistry is not maintained within these limits, localized corrosion may likely result in stress corrosion cracking. The extent of cracking during plant opera-tion would be limited by the limitation of steam'enerator tube leakage between the primary coolant system and the secondary coolant system (primary-to-secondary leakage = 0.5 gpm per steam generator). Cracks having a primary"to-secondary leakage less than this limit during operation will have an adequate margin of safety to withstand the loads imposed during normal operation and by postulated accidents. Operating plants have demonstrated that primary-to-secondary leakage of 0.5 gpm per steam generator can readily be detected by radiation monitors of steam generator blowdown. Leakage in excess of this limit will require plant shutdown and an unscheduled inspection, during which the leaking tubes will be located and plugged ~<<~q~'~~4 ~

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~, repair will be required for all tubes with imperfections exceeding the plugging limit of 40K of the tube nominal wall thickness Steam generator. tube inspections of operating lants have demonstrated the capability to reliably detect degradation that has penetrated 2(C af the origina1 tube wall thickness. Qx~s ~4 2) 0+in+

Whenever the results of sbf a5/ af any steam generator

~ tubing inservice dbhb.-CX L~TtqkQ Shstavc. ncssw,tvusA saysmhk @scgsn inspection

~,

fall into Category C-3, these results will be promptly reported to the Commis- ('ines k K) sion pursuant to Specification 6.9.1 prior to the 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 of the Technical Specifications, if necessary.

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OR lNFORMATION OW REACTOR COOLANT SYSTEM SURYEILLAHCE RE UIREHEHTS (Continued 4.4.4.4 As u

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Acce tance GQ.a Criteria

'cification LnSer4 contour of specifications.

a

~ tube from the nominal tube wall thickness, as imperfections.

i h that required by fabrication drawings or Eddy-current testing indications below 20X of if detectable, may be considered lt. I~li "i i 1 general corrosion occurring on either inside or outside of a tube.

9 3. Oe raded Tube means a tube containing imperfections greater than or equa to 20X of the nominal wall thickness caused by degradation.

5W. X De radation means the percentage of the tube wall thickness a ected or removed by degradation.

or imperfection of such severity that it exceeds

~e.pa,ir'efect means an the u in imit. A tube containing a defect is defective.

c.c. a~sa.r4 Unserviceable describes the condition of a tube if it leaks or conta>ns a defect large enough to affect its structural integrity in the event of an Operating Basis Earthquake, a loss-of-coolant

<<g accident, or a steam line or feedwater line break as specified in 4.4.4.3c., above.

~Tb I<<i i i from the point of entry (hot leg side) completely around the U-bend to the top support of the cold leg.

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 ll,. %a.a. ie,z~4 pa cy PALO VEROE - UNIT 3 3/4 4-14

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INSERTS TO PAGE 3/4 4 14 system pressure boundary.

Plu in or Re air 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. The plugging or repair imperfection depths are specified in percentage of nominal wall thickness as follows:

a. Original tube wall 40%

b. ABB-CE Leak Tight Sleeves 35%

11. T~ube Re air refers to welded sleeving as described in ABB Combusdon Engineering Report CEN-613-P "Palo Verde Units 1, 2, and 3 Steam Generator Tube Repair using Leak Tight Sleeves" Rev 01 dated January 1995 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 preventative measure. A tube inspection per Specification 4.4.4.4.a.9 is required prior to returning previously plugged tubes to service.

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ypR lNFORMATlON ONI REACTOR COOLANT SYSTEM SURVEILLANCE RE UIREHENTS Continued) condition of the tubing. This inspection was performed prior to the field hydrostatic test and prior to initial POWER OPERATION using the equipment and techniques expected to be used during subsequent inservice inspections.

ar c'c.paxe The steam generator shall be determined OPERABLE after completing the corresponding actions (plu <all tubes exceeding the plugging<cd r'~p~<

limit and all tubes containing through-wall cracks) required by Table 4.4-2. ~f~c~~a c~~a.a r e ~ a~ ra.p~(ra.g i~ ~vhav ca us'i%~ w~w 4a~Mu.wQ~~ 6vC~i4~<~ 9 a poA'%M '4%%-9 "~c'irma. Pu&G~ 'So.cwhA Ca, 4.4.4.5 orts +~a N<<~~ ~~~>

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Within 15 days following the completion of each inservice inspection ee.gavage.

of steam generator tubes, the number of, tubes plugged in each steam generator shall be reported to the Commission in a Special Report pursuant to Specification 6.9.2. oc The complete results of the steam generator tube inservice inspection shall be submitted to the Commission in a Special Report pursuant to Specification 6.9.2 within 12 months following completion of the inspection. This Special 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 pl ugged< a~ r c pa i~4-C. Results of steam generator tube inspections which fall into Category C-3 shall be reported in a Special Report to the Commission pursuant to Specification 6.9.2 within 30 days and prior to resumption of plant operation and shall provide a description of investigations conducted to determine cause of the tube degradation and corrective measures taken to prevent recurrence.

PALO VERDE - UNIT 3 3/4 4-15

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TABLE 4.4-2

-STEAH GENERATOR TUBE INSPECTION 1ST SAMPLE INSPECTION 2ND SAMPLE INSPECTION 3RO SAMPLE INSPECTION Sample Size Result Action Required Result Action Required Result Action Required A minimum of C-1 None N. A. N. A. N. A. N. A.

S Tubes per S. G.

oc tc pckb. ~~C C-2 P)u~gdefective tubes C- I None N. A. N.A.

and inspect additional Plug~defective tubes C-1 None oi- t'~e tr 2S tubes in this S. G. C-2 and inspect additional C-2 Plug defective tubes 4S tubes in this S. G.

Perform action for C-3 C-3 result of first sample Perform action for ec'~P C-3 result of first N. A. N. A, sample C-3 Inspect all ubes in All other this S. G., plug< e. S. G.s are None N. A. N. A.

fective tubes and C-1 inspect 25 tubes in Some S. G.s Perform action for each other S. G. N. A. N. A.

C-2 but no C-2 result of second additional sample Notification to NRC S. G. are pursuant to $ 50.72 C-3 (b)f2) of 10CFR Additional Inspect all tubes in Part 50 S. G. is C-3 each S. G. and plug<

OC'tkhc defective tubes.

Notification to NRC N. A. N. A.

pursuant to f50.72 lb) (2) of 10 CF R Part 50 is the number of steam generators in the unit, and n is the number of steam generator~;

S 3 % Qfhere N during an inspection

V II

fR lNFORMAT,QN GNL' REACTOR COOLANT SYSTEM BASES 3/4.4.4 STEAM GENERATORS The surveillance requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the RCS will be main-tained'. The program for inservice inspection of steam generator tubes is based on a modification of Regulatory Guide 1.83, Revision l. Inservice inspection of steam generator tubing is essential in order to maintain 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.

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 negligible corrosion of the steam generator tubes. If the secondary coolant chemistry is not maintained within these limits, localized corrosion may likely result in stress corrosion cracking. The extent of cracking during plant opera-tion would be 'limited by the limitation of steam generator tube leakage between the primary coolant system and the secondary coolant system (p'rimary-to-secondary leakage = 0.5 gpm per steam generator). Cracks having a primary-to-secondary leakage less than this limit during operation will have an adequate margin, of safety to withstand the loads imposed during normal operation and by postulated accidents. Operating plants have demonstrated that primary-to-secondary leakage of O.5 gpm per steam generator can readily be detected by radiation monitors of steam ger eratcr blowdown. Leakage in excess of this limit will require plant shutdown and an unscheduled inspection, during which the leaking tubes will be located and plugged. ~~ ~~pc ~c~ .

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 oc be required for all tubes with imperfections exceeding the plugging limit

~~p~i<'ill of 40K oi the tube nominai wall thickness. Steam generator tube inspect~ions o operating lants have demonstrated the capability to reliably detect degradation Whenever the results of oe ~5'f, ~f any steam generator

~tubing inservice that has penetrated 20K of the original tube wall thickness.(>~>~<2)

ASSs-% Lsb4a.4;riage Q4auc. n.tbwkmmt 4 us~at inspection ~~gwa.aa, fall into Category C-3, these results will be promptly reported to the Commis-sion pursuant to Specification 6.9.'rior to the resumption of plant operation. (~<<~

Such cases wi 11 be considered by the Commission on a case-by-case basis and may i

result in a requirement for analysis, laboratory examinations, tests, additional eddy-current inspection, and revision of the Technical Specifications, if necessary.

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ATTACHMENT2 COMBUSTION ENGINEERING, INC.

REPORT CEN-613-P REVISION 01 DATED JANUARY 1995 ARIZONA PUBLIC SERVICE CO.

PALO VERDE UNITS 1, 2, AND 3 STEAM GENERATOR TUBE REPAIR USING LEAK TIGHT SLEEVES FINAL REPORT

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