ML18057A540

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Proposed Tech Spec 4.14 Re Augmented Inservice Insp Program
ML18057A540
Person / Time
Site: Palisades Entergy icon.png
Issue date: 10/22/1990
From:
CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML18057A539 List:
References
NUDOCS 9011010100
Download: ML18057A540 (17)
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Text

ATTACHMENT 1 Consumers Power Company Palisades Plant Docket 50-255 PROPOSED TECHNICAL SPECIFICATION PAGE CHANGE October 22, 1990 7 Pages

,-- 9011010100 901022 PDR ADOC~ 050002~5 p PNU_

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4.14 AUGMENTED,SERVICE INSPECTION PROGRAM FOR~EAM GENERATORS 4.14.1 Each steam generator shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the requirements of Specification 4.0~5.

4.14.2 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 4.14-1.

4.14.3 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 4.14-2. The inservice inspection of steam .

generator tubes shall be performed at the frequencies specified in Specification 4.14.4 and the insp~cted tubes shall be verified acceptable per the acceptance criteria of Specification 4.14.5.

The tubes selected for each ins~rvice inspection shall includ~ at least 3% of the total number of *tubes in all steam generators; the tubes selected for these inspections shall be selected on a random basis except:

a. Where experience in similar plant~ with similar water chemistry indicates critical areas to be inspected, then at least 50% of the tubes inspe~ted shall be* from these critical areas.
b. The first sample of tubes selected for each. inservice ins~ection (subsequent to the preservice inspection) of each steam generator shall include: *
1. All nonplugged tubes that previously had detectable wall penetrations greater than 20%.
2. Tubes in those area where experience has indicated
  • potential problems.
3. A tube inspection (pursuant to Specification 4.14.5.a;B) sha 11 be performed on each se 1ec;t_ed tube_.
  • If any ~elected . __ ...

tube does not permit the passage of the eddy current probe for a tube inspection, this shall be recorded and an adjacent tube shall be selected and subjected to ~ tube inspection.

c. The tubes selected as the second and third samples (if required by Table 4.14-2) during each inservice inspection may be subjected to a partial tube inspection provided:
1. The tubes selected for these samples include the tubes

.from those areas of the tube sheet array where tubes with imperfections were previously found.

4-66 Amendment No. ~~'~,,~i,J~~,JJi,J~i TSPR9002

4.14 AUGMENTED'SERVICE INSPECTION. PROGRAM FOR,EAM GENERATORS (Cont'd)

2. The inspections include those portions of the tubes where imperfections were previously found.*

The results of each sample inspection shall be classified into one of the following three categories:

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.

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

. 4.14.4 Inspection Frequencies* - The above required inservice inspection of steam gener~tor tubes shall be performed*at the following frequencies:

a. The first inservice inspection shall be performed after* 6 Effective Full Power Months but within 24 calendar months of inaugural criticality for the steam generato~s. 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 inclucjing 'the preservice ...

inspection, result in all inspections 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.
b. If the results of the inservice inspection of a steam generator conducted in accordance with Table 4.14-2 at 40 month i nterva 1s fa 11 into Category C-3, the inspection frequency shall be increased to at least once per 20 months.

4-67 Amendment No. $$,$~,~i,J~~,JJi,J$i TSPR9002

4.14 AUGMENTED~SERVICE (Cont'd)

INSPECTION PROGRAM FOR~EAM GENERATORS The increase in inspection frequency shall apply until the subsequent inspections satisfy the criteria of Specification 4.14.4.a; the interval may then be extended to a maximum of once per 40 months.

c. Additional, unscheduled inservice inspections shall be performed on each steam generator in accordance with the first sample inspection specified in Table 4.14-2 during the shutdown subsequent to any of the following conditions:
1. Primary-to-secondary tube leaks (not including leaks originating from tube-to-tube sheet welds) in excess of the limits of Specification 3.1.5.
2. A seismic occurrence greater than the Operating Basis Earthquake.
3. A loss-of-coolant accident resulting in initiation of flow of the engineered safeguards.
4. A main steam line or main feedwater line break.

4.14.5 Acceptance Criteria

a. As used in this Specification
1. Imperfection means an exception to the dimensions, finish or contour of a tube from that required fabrication drawings or specifications. Eddy-current testing indications below 203 of the nominal tube wall thickness, if detectable, may be considered as imperfections.
2. Degradation means a service-induced cracking, wastage, wear or general corrosion occurring on either inside or outside of a tube.
3. Degraded Tube means a tube containing imperfections greater than or equal to 20% of the nominal wall thickness caused by degradation. -
4. % Degradation means the percentage of the tube wall thickness affected or removed by degradation.
5. Defect means an imperfection of such severity that it exceeds the plugging limit. A tube containing a defect is.

defective.

6. Plugging Limit means the imperfection depth at or beyond which the tube shall be removed from service and is equal to 403 of the nominal tube wall thickness.

4-68 Amendment No. $$,$~,~i,J~~,JJi,J$i TSPR9002

4.14 AUGMENTED.SERVICE INSPECTION PROGRAM FOR,EAM GENERATORS (Cont'd)

7. Unserviceable described the condition of a tube if it lea ks or contains a defect large enough to--a ff ect 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 4.14.4.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.
9. Preservice Inspection means an inspection of the full length of each tube in 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 shop hydrostatic test and prior to initial POWER OPERATION using the equipment and techniques expected to be used during subsequent inservice inspections.
b. The steam generator shall be determined OPERABLE after completing the corresponding actions (plug all tubes exceeding the plugging limit and all tubes containing through-wall cracks) required by Table 4.14-2.
  • 4.14.6 Reports
a. Within 15 days following the ~ompletion 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.

6.9.3.3b. '

b. The complete results of the steam generator lube inser~ice inspection shall be submitted to the Commission in a Special Report pursuant to Specification 6~9.3.3b 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-thi.ckness ~enetration for each indication of an im~erfection.

3~ Identification of tubes plugged

c. ** Results of steam genera for tube* iris.pect i ans that fa 11 *into Category C-3 shall require 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> verbal notification to the NRC prior to resumption of plant operation. A written followup within the next 30 day~ shall provide a description of investigations and corrective measures taken to prevent recurrence.

4-69 Amendment No. ~~,~~'~i,J~~,JJi,J~i TSPR9002

Table 4.14-1 MINIMUM NUMBER OF STEAM GENERATORS TO BE

  • INSPECTED DURING INSERVICE INSPECTION Preservice Inspection ** Yes No. of Steam Generators per Unit Two Firsi Inservice Inspection One Second & Subsequent lnservice Inspections One 1 Table Notation:
1. The inservi.ce .inspection may be limited to one steam generator on a rotating schedule
  • encomp,assing 6% of the tubes if the results of previous inspections indicate that all steam generators are performing in a like manner. Note that under some circumstances, the operating conditions in one or more steam generators may be found to be more severe than those in other steam generators. Under such circumstances the sample sequence shall be modified to inspect the most severe conditions.

4.69a Amendment No .

. TSPR9002

c TABLE 4.14-2 STEAM GENERATOR TUBE INSPECTION I

lST 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 S.G.

C-2 Plug defective tubes C-1 None* N/A N/A and inspect additional I 2S tubes in this S.G. C-2 Plug defective tubes C-1 None and inspect additional 4S tubes in this S.G. C-2 Plug defective tubes C-3 Perform action for C-3 result of first Sample C-3 Perform action for I C-3 result of first N/A N/A Sample C-3 Inspect all tubes in All other None N/A N/A this S.G., plug de- S.G.s are fective tubes and C-1 inspect 2S tubes in each other S.G. Some S.G.s Perform action for .. N/A N/A I C-2 but no C-2 result of second additional sample 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> verbal S.G. are ,_

notification to NRC C-3 with written follow up within next Additional Inspect all tubes 30 days S.G. is each S.G. and plug C-3 defective tubes. N/A N/A s =3 N

- % Where N ts the number of .steam* generators in the unit, and n*is the number of steam generators n inspected ~uring an inspection 4-69b Amendment No.

TSPR9002

4.14 AUGMENTED S~RVICE INSPECTION PROGRAM FOR~EAM GENERATORS Basis (Coi -

The Surveillance Requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the PCS will be maintained. The program for inservice inspection of steam generator tubes is based on a modification of Regulatory Guide 1.83, Revision 1. Inservice inspection of steam generator tubing is essential in order to 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 operation would be limited by the limitation of steam generator tube leakage limit between the primary coolant system and the secondary coolant system that is stated in Technical Specifications 3.1.5. 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 experience has demonstrated that primary-to-secondary leakage in excess of the limits stated in Technical Specification 3.1.5 can readily be detected by radiation monitors of steam generator blowdown or condenser off-gas. Leakage in excess of this limit will require plant shutdown and an unscheduled inspection, during which the leaking tubes will be located and plugged.

Waste-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 will be required for all tubes with imperfections exceeding the plugging limit of 40% of the tube nominal wall thickness (ASME B&PV Code,Section XI, IWB 3521). Steam generator tube inspections of operating plants have demonstrated the capability to reliably detect 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 promptly reported to the Commission prior 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 Spec1fications, if necessary.

4-69c Amendment No.

TSPR9002

\I ATTACHMENT 2 Consumers Power Company Palisades Plant Docket 50-255 MARKED UP TECHNICAL SPECIFICATION PAGES October 22, 1990 8 Pages

4.13 (Continued 4-66 Amendment No. ' ' '

September 5, 1985 TSP0985-0287A-NL04

  • ~

.. e.

I 4-67 *Change No 20 Amendment No. 45 January 19, 1979 tSP0987-0145-NL04

4. 14 Augmented Inservice Inspection Program for Steam Generators Applicabilitz Applies to the tubes within both steam . generators.

Objective To provide assurance of continued integrity of the steam gener tubes over their service lifetime.

4. 14. 1 Inspect ns will be performed at an in~Tf'al of up o 24 calendar months a er the previous inspection.* Additi al tube /

inspection shall be performed when primary to condary leakage not includin leaks originating from tube to t e sheet welds) exceeds the 1 kage limits delineated in Spe fication 3.1.Sd.

4.14.2 Ins ection Re 4.14.2.1 For specificatio, "tube" refers to that portion of th steam generat r tubing from the point of entry on the cold legs de to the p'support of the cold leg, or from the point of on th hot leg side to the top support of the cold leg.

4.14.2.2 Tubes requiring inspection w include all unplugged tubes with eddy current indications o tu~ wall degradation greater than or equal to 30% in either of the pr Yious two inspections. Limited access tubes subject to his requ ement, which result in significant added rad . tion exposur to inspect, shall be inspected during an interval n t to-exceed two onsecutive inspections.

4.14.2.3 Tubes spection will also in ude a random sample of 2% of tubes and 1% of the col leg tub~s in each steam generato

  • Random samples shall be awn from those unplugged tu that do not have tube wall d radation identified as greater to 30% during the inspections.
  • The be extended to 30 months if the mean degrada increase for steam generator inspection interval was less +1%.

exception is allowed from the periodic eddy current .I n due by July 4, 1990. This exception is valid for a limit I to the September 1990 refueling outage when the steam generato s I cheduled to be replaced. If for any reason the steam generators a I no replaced, the required inspections of Technicai Specification 4.14 I s all be completed prior to startup from the 1990 refueling outage.

  • I 4-68 Amendment No. JJ, J2, l~f, lt2.

June 28, 1990 TSP0790-0055-NL04

4.14.2.4 A baseline inspection of all newly installed sleeves shall be performed prior to plant operation. Inspec~ion of each installed sleeve shall be performed once per three steam generator tube

  • inspection intervals, with approximately one-third of the sleeves inspected during each inspection interval.** In the event of sleeve degradation the sleeve inspection interval shall be evaluated.

4.14.2.5 In the case where a tube is sufficiently restricted to prev, nt ssage of an 0.540-inch diameter probe (blocked), all un ugged tu es surrounding the blocked tube will be gauged to en acce table denting levels.

4 .14. 2. 6 In the ~ent that tube inspections are required due to primary to secondarj\leakage, a 6% sample of unplugged tubes n tne affected leg(s) in ach steam generator with leakage in v olation of the limits of S cification 3.1.Sd shall be inspec d.

4.14.3 Su 4.14.3.l If the inspection or 4.14.2.6 yields results that one or more of the following criteria, then additional sampl of unplugged ubes shall be inspected according to Figure 4.1 .1.

a) More than 10% of the detectable wall degradation (grea through wal~)

where no previous degra b) More than 10% of d tubes in a leg exhibit further wall degradation a 10% increase in through wall degradation).

c) *.More* tha1t 1% Gf th*. inspected tub in a leg have indications of tube wall gradation in excess the repair criteria of Specificatio 4.14.4 where no wall de radation greater than 30%.~* de c~d in the previous two 4.14.3.2 In hat any of the above limits are ceeded, prompt notificatio . to. .. the Nuclear Regulatory. Collllllisaio pursuant to 2 sull occur ..

the in"stalled sleeves during th* inspection beginning in is not required.

4-68a Amendment No. Jf, J2, ttt, 132 June 28, 1990 TSP0790-00SS-NL04

'("

.14.3.3 When applying the criteria of Specification 4.14.3.1 to.the

  • **
  • inspection sample of Specification 4 .14 .2. 6, the leaking* tubes I that initiat.ed the inspection are not to be reflected in the I sample inspection results. I I

4.14.3. *When applying the criteria of Specification 4.14.3.l to the tub I sample inspection results, the samples are not to be treated I umulatively. The criteria shall be applied only to the I pe~tion results from the immediate additional sample wh I

  • dee ding whether or not to inspect the n.ext additiOnal s ple I int progression of Figure 4.14.1: I I

I

/.

4.14.4.1. A tube shal be declared defectiv~ and shall be using I methods cons tent with Specification 4.14.4.5 I following cond tions: I I

a). Inspection o the tube produces an e y current'indication I of volumetric egradation exceeding the limits as listed in l Specifications .14.4.2 and 4.14. /.

/

b) Inspection of the ube the presence of a crack ..

  • I indication. I

.I c) Inspection of the tube uces an eddy current indication of I tube wall degradation t is uninterpretable "and was greater I than or equal to 45%-d the previous inspection. I

/.

d) Tube restrictions of an 0.540-inch diameter I

  • probe. I I

4.14.4.2 The* following volum ric degradation ts shall be used to. l iderit_ify defectiv tubes: I I .

a) greater than 51% through identified by the I

... cuITent technique or equivale t * .I-b) Indic tions greater than 58% through wall dentified by a bob n probe eddy current technique or_equi I

c) ltiple indications greater than 29% through identified I

~y a bobbin probe eddy current techl'.!-ique or equi I 4-68b Amendment No. Jf, J%, 11 March 24, 1988 TSP0987-0145-NL04

\, .

4.14.4.3 The volumetric degradation limits for regions in the tube/sleeve I assemblies are as follows:

I I

Region I I

1. The undeformed region of the Sleeve degradation > 28% a I tube/sleeve assembly containing tube degradation exceeds I the original imperfection degradation limit for a I requiring sleeving. unsleeved tube. I I
2. region containing the expansion Either sleeve degr ation I join . Specifically, the region > 19% when tube d gradation in I of th tube/sleeve assembly bounded region 1 exceed the I by line approximately 1/4 inch and degradation 1 it for an r*

2 inches n board from the sleeve unsleeved se ion; or tube I ends. degradatio in region 2 is I greater t an the degradation I limit f an unsleeved tube. I I

. 3. The region of th tube/sleeve Tube egradation exceeds the I assembly contain! approximately adation limits for an I 1/4 inch of each en of the assembly. leeved tube. I

-/

4 . 14

  • 4 . 4 If the mean degrada ion the interval since* the I previous steam gener or inspectio .~han or equal to 1%, I then new degradation 1 to the NRC for I review and approval pri I I

4.14.4.5 Plugging each end of a defe tive tube is considered as acceptable I repair for all cases in S ec !cation 4.14.4.1. However, sleeving I may be selected as an a repair method. NRC approval for I the sleeving method is rior to repairing. I I

4.14.5 I I

submitted to the I of completion of the I I

I Basia I I

ce for establishing the requirements specification is I from Regulatory Guides 1.83 and 1.121, Combu ion Engineering I dard Te,chnical Specif icadons, and past experien e with the I alisadea steam generator problems*;-: I I

In October 1974, the secondary side water chemi~try I changed from coordinated phosphate treatment to all volatf e I treatment in order to arrest the degradation that had been served I in the steam generators~ Both intergranular attack and wasta e I were present at the time and appeared to be growing. The ste I generators suffered from excess leakage in January 1973, in I August 1973, and in May* 1974. I 4-68c Amendment No. 39, J2, 112 March 24, 1988 TSP0987-014S-NL04

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.FIGURE 4.14.l - SUPPLEMENTARY SAMPLING FLOW 'CHART I I

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I SPECIFICATIONS

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I 4.14.2.2 I PASS 4.14.2.3 I I

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REPAIR I ADDITIONAL INSPECTION I SAMPLES IN AFFECTED I LEG(S) AS AGREED TO I BY THE NRC I f PASS I

~ SPECIFICATION FAIL I jl. 4. 14. 2. 6 1 - - - - - - - - t I I

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'°OD *0 I OD

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N PASS - STEAM GENERATOR I.EG(S) PASSING THE CRITERIA OF SPECIFICATION 4.14.3.l FAIL - STEAM GENERATOR LEG(S) FAILING THE CRITERIA OF SPECIFICATION 4.14.3.1 I

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4 .14 Basis (Continued) I I

In March 1982, a primary to secondary leak in excess of the technical specification limit of 0.3. gallons per minute occurred in _I steam generator 'A'. Initial eddy current examination of possible I leakers with the bobbin probe showed no new tube defects. I Subsequent examinations with a pancake type eddy current probe I additional bobbin probe examinations showed the leaking defect I -

be through wall with a circumferential orientation. At this oint; I Consumers Power Company committed to develop a pancake prob (4C4F) I c for use in the 1983 refueling outage. I e 1983 bobbin coil inspection confirmed that there wa no I de adation*increase in the steam generators. Howeve , a 100% I insp ction of the steam generators with the 4C4F pro e revealed a I numbe of circumferential crack indications that h apparently I been in existence for some time but had gone unde ected during .* I previous obbin probe examinations. In additio , a number of I intergranu ar attack indications that were no previously I recognized re also characterized throughou both generators using I the 4C4F prob

  • I Inspection tech ques are used which in combination I are capable of me suring wastage and attack within I the presence of ~e I In Specification 4.1 1, the inspe ion interval requirement has I been established at a ximum of to 30 months. While the intent I is to conduct an inspect on dur g each scheduled refueling outage, I the long outage durations xpe lenced at the Palisades Plant I indicate a 30 month rather n a 24 month interval limit is I appropriate to prevent unsc uled shutd_o.wns for inspection. I
  • The inspection of a 6% s ple o tubes in steam generator legs I exhibiting leakage is i tended t provide information as to whether I--

or not degradation is ncreasing. The leaking tube{s) will not be I included in the init al inspection le results. Inclusion. of I the leaking tubes uld distort* the i spection results and lead to I unnecessary insp tions and personnel diation exposure. Such I tube leakage co d be due to isolated e ects rather than general I degradation i I The supplem tary sampling requirements in I are intend d to provide guidance in determini the appropriate I action i the event that any of the *criteria o Specification I 4.14.3. are exceeded. These requirements will rve*to help I the nature and extent of additional or ne degradation in I team generators. The results of inspection s les are not I tr ated cumulatively because as the nature and extent of the I ditional or new degradation becomes clearer with the nspection I of* more tubes, *the criteria for selecting tubes for addi ional I samples may change. Therefore, it is not appropriate to mbine I the results of two separate inspection samples when the tub ./

selection criteria differ between them. I

.The volumetric degradation limit for the 4C4F eddy current '/

technique is based upon the findings of the qualification progra

  • I Details of the 4C4F technique qualification program are in the I 1983/1984 Steam Generator Evaluation and Repair Report, l Docket 50-255, License DPR-20. I 4.,..69 Amendment No. Jf, J2, 112 March 24, 1988 TSP0987-0145-NL04
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