ML20101G964
| ML20101G964 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 06/19/1992 |
| From: | HOUSTON LIGHTING & POWER CO. |
| To: | |
| Shared Package | |
| ML20101G940 | List: |
| References | |
| NUDOCS 9206290069 | |
| Download: ML20101G964 (9) | |
Text
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ATTACllME!JT 2 PROPOSED CilAllGE TO TECH!iICAL SPECIFICATIOli 4.7.9 l
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9206290069 920619 ADOCK0500g8 PDR P
MISC \\92 085.003
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ptANT SYSTEt15
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ATTACHMENT 2
3/4.7.9 SNUBBERS ST.HL.AE. 41M
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1%CE 1 OF fd millM COND1110LL0f OPERAT10N
The only snubbers excluded from the requirements are those installed on nonsafety-related systems and then only if their failure or failure of the system on which they are installed would have no adverse effect on any safety-related system.
APPLICABILITY:
MODES 1, 2, 3, and 4.
H3 DES 5 and 6 for snubbers located on systems.tequired OPERABLE in those MODES.
ACTION:
With one or more snubbers inoperable on any system, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> replace or re-store the inoperable snubber (s) to OPERABLE status and perfort an engineering eval-
.uation per Specification 4.7.99 on the attached component or oeclare the attached system inoperable and follow the appropriate ACTION statement for that system.
EVPlfjut#CE RE001PEMEh'TS 4.7.9 Each snubber shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program in lieu nf the requirements of Specification 4.0.5.
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a.
Inspection Types As used in this specification, type of snubber shall mean snubbers of the same design and manufacturer, irrespective of capacity, b.
Visual Inspections 1143E RT " A
- Snubbers are categorized as inaccessible or accessible durino reactor op,,,t,on, a cs ce tnesc-g,c;p g n,cm 4% a.ma g y BEE ATTACHEE
-f4M4-inserv4< 0 vi c e:1 inspec-t4en Of each type of :nubber :h:11 be PMC
-per4emed O' ter ' m nth; but-within-10 months-of-ccr.nntir,g POWE4-
-OPHAT40N-end-+ha41-4nelvde :11 :nubber.
I f all snut+then--of-eAE4.-
-type tre fcund C#GA&M-49r4ng-the-f4Mt-4nsmke-vbe4-inspeM4+e,
-tte :: end -intervice vice:1 i pee 44en-sha44-t*e-performed at--the-f4+st.
n refecling-outege.
Otherwise -ebsequent-v4+ual-4nspeet4en: hall be-r perfered i~ ::ar-duce eith the fell:e!ng ::Mdulet-(
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SOUTH TEXA5 - UNITS 1 & 2 3/4 7-21
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~$1E iiMENT Z.
OT H1 AE 483 4
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' t.GC 10F B INSERT A (For Tech. Spec. 4.7.9 b)
Each of these categories (Inaccessible and Accessible) may be inspected independently or jointly according to the schedule determined by Table 4.7-2.
The visual inspection interval for each population or category of snubber shall be determined based upon the criteria provided in Tabic 4.7-2 and the first inspection interval determined using this criteria shall be based upon the
- previous inspection interval as established by the requirements in effect before amendment (*).
(*)
NRC will include the number of license amendment that implements thiu change.
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MISC \\ 92-08 5. 003
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[ ATTACHMENT
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. glu. AC. 4 0 4 PLANT SYSTEMS
!UM3M6 1
1LfDd'IllLOCIEQQiHENTS f.CMtim!tdI k~
b.
Visual Inspections (Continued)
Inoperable Snubbers of Each Type Subsequent Visual per insp 4mLPeriod Inspection Ptric e **,
TNSE R T ',B'
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O le r;taths's 2C 1
7 months t 25%
SEE ATTAcais.p 2
6 months 1 25%
3,4 124 days i 25%
6 5,6,7 2 25%
eore 31 days (
c.
Visual Inspection Acceptance Criteria Visual inspections shall verify that:
(1)*thefe ne no visible indications of damage or impaired OPERABILITY, (2) attachments to the foundation or supporting structure are functional, and (3) fasten-ers for attachment of the snubber to the component and to the snubber anthorage are functional.
Snubbers which appear inomerable as a result of visual inspections * :y be determined OPER G E for the purpose of establishing the next visual inspection interval, provided that: ft} the cause of the rejection is clearly established and L
remedied for that particular m v'ubcr and for other snubbers irresoec-tive of type that may be generically susceptible; and (4) the affected I
snubber is functionally tested in the as-found condition and determined i
OPERABLE per Specification 4.7.9f.
All snubbers' connected to an
- ""j inoperable common hydraulic Guid reservoir shall be counted as JW56RT,C,,-+ %eMie mbbm, g
en$ c reclarsif. ied acceptable d.
Transient Event inspection b
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f4GE An inspection shall be performed of all snubbers attached to sections of systems that have experienced unexpected, potentially damaging transients as determined from a review of operational data and a visual inspection of the systems within 6 months following such an event.
In addition to satisfying the visual inspection acceptance criteria, freedom-of-motion of mechanical snubbers shall be verified using at least one of the following:
(1) manually induced snubber movement; or (2) evaluation of in place snubber piston setting; or (3) stroking the mechanical snubber through its full range of travel.
'M ction interval for each type of snubber shall not be len th at a time unless a generic problem
. Identified more than on and corrected; (in thai D the inspection terv3T~Eay be lengthened one step the first time and twn ste er if no inoperable snubbers of that type are found.
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"The p;ouis cation 4.0.2 are not applicab e.
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SOUTH TEXAS - UN1151 & 2 3/4 7-22 l
l l ATT/sCHMENT 2.
$T lh AE. 9 34
[DSERT '8"
^ 2E 4 OF 8 TABLE 4.7-2 SNUBBER Y15UAL INSPECTION INTERVAL NUMBER OF UNACCEPTABLE $NUBBERS Population Column A Column B Column C or Category Extend Interval Repeat In @rval Reduce Interval (Notes 1 and 2)
(Notes 3 and 6)
(Notes 4 and 6)
(Notes 5 and 6) 1 0
0 1
80 0
0 2
100 0
1 4
150 0
3 8
200..
2 5
13 300 5
12 25 400 8
18 36 500 12 24 48 750 20 40 78 1000 or greater 29 56 109 Note 1:
The next visual inspection interval for a snubber population or cate-gory size shall be determined based upon the previous inspection interval and the number of unacceptable snubbers found during that interval. Snubbers may be categorized, based upon their accessibility during power operation, as accessible or inaccessible.
These categor-ies may be examined separately or jointly.
However, the licensee must make and document that decision before any inspection and shall use that decision as the basis upon which to determine the next inspection interval for that category.
Note 2:
Interpolation between population or category sizes and the number of unacceptable snubbers is permissible. Use nest lower integer for the value of the lirit for Columns A, B, or C if that integer includes a fractional value of unacceptable snubbers as determined by inter-polation.
Note 3:
If the number of unacceptable snubbers is equal to or less than the number in Column A, the next inspection interval may be twice the previous interval but not greater than 48 months.
If the number of unacceptable snubbe 3 is equal to or less than the Note 4:
number in Column B but greater @7[the number in Column A, the next inspection interval shall be besameasthepreviousinterval.
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IN GER T " 6"
%Bl. E 4,7 2 (C ord T 'p )
DJu DBE R Visub u ins tEcTio N I MTCRVA L.
Note 5:
If the number of unacceptable snubbers is equal to or greater than the number in Column C, the next inspection interval shall be two-thirds of the previous interval.
However, if the number of unacceptable i
snubbers is less than the number in Colur.n C but greater than the
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number in Column B, the next interval shall be reduced proportionally by interpolation, that is, the previous interval shall be reduced by a factor th.t is one-third of the ratio of the difference between the number of unacceptable snubbers found during the previous interval and the number in Column B tu the difference in the numbers in Columns B dnd C.
Note 6:
- The provisions of Specification 4.0.2 are applicable for all inspec-tion intervals up to and including 48 months.
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ATT ACHL8ENT 2-j
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INSERT C (For Tech. Spec. 4.7.9 c) unacceptable and may be reclassified as acceptable for determining I
the next inspection interval provided that criteria (1) and (ii) above are met.
A review and eve.Juation shall be performed and documented to justify continued operation with an unacceptable snubber.
If continued operation cannot be justified, the snubber shall be declared inoperable and the ACTION requirements shall be met.
MISC \\92-085.003
ATTACHVENT 2.
PLANT SYSTEMS
- M W /E-434
- M g r l._. Of_ R.
L EASES t
SNUEBERS (Continued)
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with Section 50.71(c) of 10 CFR Part 50.
The accessibility of each. snubber shall be determined and approved by the Plant Operations Review Committee. The detereination shall be based upon the existing radiation levels and the expected time to perform a visual inspection in each snubber location as well as other f actors associated with accessibility during plant operations (e.g., temperature, atmosphere, location, etc.), and the recomendations of Regulatir,' Guides 8.8 and 8.10.
The addition or deletion of any hydraulic or rechanical snubber shall be made in accordance with Section 50.59 of 10 CFR Part 50.
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The visual inspection trequency is based upon maintaining a constant level of snubber protection to eash safety related syste:Sduring an earthquake J
.r severe transient. Therefore, t % required inspection interval varies inversely with the observed snuR(
L ' lures on-a-<J ven4yste& anti is detercined
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by the number of inoperable 4rdw e !.vnd-4 ardng-a nd nspection-o f-eac h-systee-i I rM r.c T )
h-o rder-to-e stabl i sh--the -inspe J n irsquency-for.-each type-of-snubber-en-e-( g> ~r T
.sa fetynela ted4ys tw.., a-w,5-a numed-tha tr-thof requmcy-o f-s nubbee-f e H um-(c and-initiating-+ vents is-ccastanta.ith-Mas-and--that the f ailure-of-any-snubbec on-that-systeHould-cause-the-system-to-be-unprotected-and-to-result 4n-feHure- },gg r
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-derifvg,an-swu+ed-init4at4 Ag-event.
Inspecti"s perforced before that interval
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has elapsed may be used as a new reference pc.mt to determine the next inspection.
However, the results of such early inspections perforced befcre the original required tire interval has elapsed (nominal time less 25%) ray net be used to lengthen the required inspection interval.
Any inspection whose results require j
a shorter inspection interval will override the previous schedule.
The acceptance criteria are to be useo in the visual inspection to detertine OPERA 31LITY of the snubbers.
For example, if a fluid port of a hydraulic snubber is found to be uncovered, tm snuaber shall be declared,inepereMe--and-p"'
eeWno t-t Mete mi ned-CGAM-vu-w+t4ena4-t+s-t-imJr E.
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To previde assurance of snubber functional reliability, one of three (v'
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f unctional testing cethods is used with the ste.ed acceptance criteria:
'C C crf M umt D 1.
Functionally test 10% of a type of snubber with an additional
,s 1C% tested fcr each functional testing f ailure ir 2.
Functionally test a sample size and detemine sa ple acceptan:e or j
rejection using Figure 4.7-1, or 3.
Functionally test a representative sample size and determine sar?le acceptance or rejection using the stated equation.
l Figure 4.7-1 was developed using "Wald's Sequential Probability Ratio Plan" as described in " Quality Control and Industrial Statistics" by Acheson J. Duncan.
I Permanent or other exemptions from the surveillance program for individual snubbers may be granted by the Co=ission if 3 justifiable basis for exemption i
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SOUTH TEXA5 - UNITS 1 & 2 E 3/4 7-5 Unit 1 - kendment No.19 Unit 2 - Mendment No. 9 i
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ATTACHMENT Z
$T HL AE. $l31
{PACEE20F b INSERT D -(For the bases of Tech. Spec. 3/4.7.9) inoperable = snubbers found during the previous inspection, the total population or category size, and the previous inspection interval.
Snubbers may be categorized, based upon their accessibility during power operation, as accessible or inaccessible.
These categories may be examined separately or jointly.
However, that decision must be made and documented before any inspection, and that decision shell be used as the basis upon which to determine the next inspection interval for that category.
INSERT E (For the bases of Tech. Spec. 3/4.7.9) unacceptable and may be re-classified as acceptable for determining the next inspection interval provided that (1) an analysis for the hydraulic fluid of that particular snubber had indicated that the fluid still meets its required specifications and (2) the affected snubber is functionally tested in the as-found condition and determined OPERABLE per Specification 4.7.9 f.
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l' MISC \\02-C85,003
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