ML17286A558
| ML17286A558 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 01/18/1991 |
| From: | WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | |
| Shared Package | |
| ML17286A557 | List: |
| References | |
| NUDOCS 9101240081 | |
| Download: ML17286A558 (11) | |
Text
1 PLANT SYSTEMS 3/4.7.4 SNUBBERS CONTROLLED COPY LIMITING CONDITION FOR OPERATION 3.7.4 All hydraulic and mechanical snubbers shall be, OPERABLE.
APPLICABILITY:
OPERATIONAL CONDITIONS 1, 2, and 3.
OPERATIONAL CONDITIONS 4 OO I
d P
I I d 0 ERREEE I
OPER TE IIII COND ITIONSICI'.
ACTION:
With one or more required 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 restore the inoperable snubber(s) to OPERABLE status and perform an engineering evaluation per Specification 4.7.4g on the attached component or declare the attached system inoperable and follow the appropriate ACTION statement for that system.
d'URVEILLANCE RE UIREMENTS 4.7.4 Each snubber shall be demonstrated OPERABLE by performance of ihe following augmented inservice inspection program and the requirements of Specification 4.0. 5.
Ins ection T
es As used in this specification, type of snubber shall mean snubbers of the same design and manufacturer, irrespective of capacity.
b.
Visual Ins ections
~~e.~~- es
)v sGILt h
Snubbers are categorized s inaccessible or accessible during reactor operation.
Each of these ~cups (inaccessible and accessible) may be inspected independently according to the schedule b
econ-efeach-type-e$ -snubb~haR-be-performed a~e ~
hs but within 1Q months of commencing POWER OPE f
nd shall include a
lic and mechanical snubb all snubbers of each type on any system d
during the first inservice visual inspectio secon 'e visual inspection of that system e performed at the first re u 'age.
Othe su sequent visual inspections of a,given system sha II ~'RIR III 8Unless the removal'f snubber(s) for maintenance or testing is justified by engineering analysis.
MASHINGTON NUCLEAR " UNIT 2 3/4 7-10
'91.01240081 9101l8
!PDR AQOCK 05000397
~P PDR Amendment No.
4O
coMTzoLLso copv o
~
d
~
b p
r PLANT SYSTEMS SURVEILLANCE'E RE UIREHENTS Continued y,p~,z 4g Tel l
%.'7-l 4o.4nopera&eSnubbers-
-Eaeh-Type-,on-hny-Sys-te er n
e ion Period 1
2 3
,6,7rSor bsequ~
Ins
'riod*¹
- months,
+25,-
12 months i 25K 6 months i 25X s
i'25'2 days a
de. rwr'.Q C.
gAr.=>
gN J.-,.NA'I Yisual Ins ection Acce tance Criteria
+lac.
sasst,loL ci Visual inspections shall verify that: (1) %here-ave no visible indi-cations of.dama e or impaired OPERABILITY; (2) attachments to the oun ation or suppor sng s ruc ure are -secure, and (3) fasteners for attachment of the snubber.to the component and to the snubber anchorage are seeure.
Snubbers which appear inopersb'le as a result
(;Nd,s u]
o v)sua
>nspections may-be-detera4oed-6PERABhE-for the purpose of establishing the next visual inspection interval, provided that:
(1) the cause of the rejection is clearly established and remedied for that particular snubber and for other snubbers irrespective of fp~ tt t p b E
1 11p ptibl; d tpi affected snubber is functionally tested in the as-found condition and d
P OPERABLE p dp if'i
- d. f. Af.
A1 1 Pb d
to an inoperable common hydraulic fluid reservoir shall be counted as p tt bb~*
Pp
-t d
~ess4g-4he-suave-'Aance-schedule for-each-ofthe-r&eted-systems.
d.
Transient Event Ins ection An inspection shall be performed of all hydraulic and mechanical 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 cr'iteria, 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.
~Th thonmt~~for-each 'type-of-snubber-on-a~me~ste~h ot~
be lengthened more an-on~Mp at a time unless eneri em has been identified and corrected; in th 4.nY-=Eh
>spec~ 'al may be
- lengthened o
ep-&
erst time and two steps thereafter if no erablw mob ebs-ofthWtgp~reMoundmrr=tha~yYttm.
r Nt~ '
f-t
'N N~
ppN WASHINGTON NUCLEAR " UNIT 2 3/4 V-u.
Amendment No.
40
L
Insert A (page 3/4 7-10) determined by Table 4.7-1.
The visual inspection interval for each type of snubber shall be determined based upon the criteria provided in Table 4.7-1 and the first inspection interval determined using these criteria shall be based upon the previous inspection interval as established by the requirements in effect before amendment (*).
Insert 8 (page 3/4 7-11) shall be classified as unacceptable and may be reclassified acceptable Insert C (page 3/4 7-11) unacceptable for determining the next inspection interval.
A review and evaluation 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.
- NRC will include the number of the license amendment that implements this change.
TABLE 4.7-1 SNUBBER VISUAL INSPECTION INTERVAL NUMBER OF UNACCEPTABLE SNUBBERS Population or Category Notes 1 and 2
Column A
Column B
Extended Interval Repeat Interval
~66 d
6 LNNd6 Column C
Reduce Interval Notes 5 and 6
1 80 100 150 200 300 3
5 12 13 25 400
-500 750 1000 or greater 8
12 20 29 18 24 40 56 36 48 78 109 Note 1:
Note 2:
Note 3:
Note 4:
The next visual inspection interval for a
snubber population or category 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 accessibil-ity during power operation, as accessible or inaccessible.
These categories 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.
Interpolation between population or category sizes and the number of unacceptable snubbers is permissible.
Use next lower integer for the value of the limit for Columns A,
B or C if that integer includes a fractional value of unacceptable snubbers as determined by interpolation.
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 snubber is equal to or less than the number in Column B but greater than the number in Column A, the next inspection interval shall be the same as the previous interval.
If the number of un'acceptable 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 snubbers is less than the number in column C
but greater than the number in Column B, the next interval shall be reduced proportionally by interpolation, that is, the previous interval shall be reduced by a factor that 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 to the difference in the numbers in Columns B and C.
The provisions of Specification 4.0.2 are applicable for all inspection intervals up to and including 48 months.
0 PLANT SYSTEMS BASES CONTROLLED COPY 3/4.7.3 REACTOR CORE ISOLATION COOLING SYSTEM (Continued)
Mith the RCIC system inoperable, adequate core cooling is assured by the OPERABILITY of the HPCS system and justifies the specified 14 day out-of-service period.
The surveillance requirements provide adequate assurance that RCIC will be OPERABLE when required. 'lthough all active components are testable and full flow can be demonstrated by recirculation during reactor operation, a
complete functional test requires reactor shutdown.
The pump discharge piping is maintained full to prevent water hammer damage and to start cooling at the earliest possible moment.
3/4.7..4 SNUBBERS All snubbers are required OPERABLE to ensure that the structural integrity of the Reactor Coolant System and all other safety-related systems is maintained during and following a seismic, or other event initiating dynamic loads.
Snubbers excluded from this inspection program are those installed on nonsafety-related systems gand 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.
Dur-ing shutdown, snubbers which are redundant per engineering analysis can be removed for maintenance and/or testing and are excluded from the operability requirements.
Snubbers are classified and grouped by design and manufacturer but not by size.
For example, mechanical snubbers utilizing the same design features of the 2-kip, 10-kip, and 100-kip capacity manufactured by Company "A" are of the same type.
The same design mechanical snubbers manufactured by Company "B" for the purposes of this Technical Specification would be of a different type, as would hydraulic snubbers from either manufacturer.
A list of individual snubbers with detailed information of snubber loca-tion and size and of system affected shall be available at the plant in accord-ance with Section 50.71(c) of 10 CFR Part 50.
The accessibility of each snubber shall be determined and approved by the Plant Operations Committee.
The deter-mination 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 factors associated with accessibility during plant operations (e.g., temperature, atmos-phere, location, etc.),
and the recommendations of Regulatory Guides 8.8 and
- 8. 10.
The addition or deletion of any hydraulic or mechanical snubber shall be made in accordance with Section 50.59 of.10 CFR Part 50.
e-v+sua4-esp econ-4'-frequency i~based-upon-maietaining-a-eons&n of snubber ote to each safety-related system. The, e required inspection interval varies wit e-o e
snubber failures on a given system and is dete ed-b e
num
-4no able snubbers found during an ins e
or er to establish the inspection freque ch type of d '~
MASHINGTON NUCLEAR - UNIT 2 B 3/4 7"2 Amendment No.
52 (change dne to repagination i
previously Amend.
$40)
~
~
CONTROLLED COPY PLANT SYSTEMS BASES 3/4.7.4 SHUBBERS (Continued)
~
~
~
~
~
~
~
R snu at system could cause the system to be unprotected a
o-su t in failure during a
d initiating event.
Inspectio er rmed before that interval has elapsed may e
-e s
a new r e point to determine the next inspection.
However, the resul inspections perform<ed before the original required ti 'al has
- elapsed, (nom less 25K) may not be used to en he required inspection interval.
Any insp m
hose results er-ter
'map
'-the-prev-i+us-sch mine D
IpdrihiTY-os snubbers.
For exampie, i~-fjord-inir o.
a hydraulic snubber is foun be-unsevere, the-snub shall be declared inoperable and e-determined-0&GRAM~+
functus To p'rovide assurance of snubber functional reliability, one of two functional testing methods are used with the stated acceptance criteria:
1.
Functionally test l(C of a type of snubber with an additional 5
tested for each functional testing failure, or 2.
Functionally test a sample size and determine sample acceptance or continue testing using Figure 4.7-1.
V WASHINGTON NUCLEAR " UNIT 2 B 3/4 7-3 Amendment Ho.
54
r
Insert to Bases pages B 3/4 7-2 and 7-3 The visual inspection schedule is based on the number of unacceptable snubbers found during the previous inspection in proportion to the sizes of the various snubber populations or categories.
A snubber is considered unacceptable if it fails the acceptance criteria of the visual inspection.
Snubbers may be categorized, based upon their accessibility during power operation, as accessible or inaccessible.
These categories may be examined separately or jointly.
The decision to examine these categories separately or jointly shall be made and documented before the examination
- begins, and cannot be changed during the examination.
The inspection interval is based on a fuel cycle of up to 24 months and may be as long as two fuel cycles, or 48 months for other fuel cycles, depending on the number of unacceptable snubbers found during the previous visual inspection.
The examination interval may vary by a 25 percent to coincide with the actual outage.