ML20214J108

Proposed Tech Spec 3/4.7.7,revising Requirements for Snubbers

ML20214J108
Person / Time
Site:	Davis Besse
Issue date:	03/12/1987
From:	TOLEDO EDISON CO.
To:
Shared Package
ML20214J100	List: ML20214J098 ML20214J104 ML20214J108
References
TAC-65069, NUDOCS 8705270648
Download: ML20214J108 (9)

Text

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. Docket No. 50-346 '

Lic:l;nac No. NPF-3 i Sarici No. 1346 -

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PtANT SYSTEns 1

{ , 3/4.7.7 SNUB 8tR$ , , l i \

j L151IDG_CDFDIIl0M.IOR.DPEMIION '  ;

t 3.7.7 All safety related soubbers shall be OPERAtt.E. ,

,t l APPLICA8tt,17Y: N00E5 1, 2, 3 and 4. (H00ES 5 and 6 for se'ubbers located  !

) en systems required Op1RAB!.E is these MODES). '

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j ACTIONt i

) a. With one or more snubbers (noperable 1. withia 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> j replace or restore the inoperable snubber (s) to OPERAtt.E

status, or 2. verify systee operability with the snubber (s) ,

l inoperable by engineering evaluation withia 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />; er -

3. declare the supported subsystem inoperable and follow ' l j -

the appropriate ACTIOW statement for that system.  ;

l and, for snubbers which have failed either the visual er  !

l functional tests t

i i b. Perform an engineering evaluaties within to days te deter-J .

eine it any safety-related systes er composest has bees I adversely affected by the inoperability of the saubber and

• l if the snubber nede of failure has imparted a sigstficant  ;

effect er degradaties es the supported composest er systee.1 i

,' The previsions of Technical Specificaties 3.0.4 are not  ;

, applicable for the componeet, or system. '

}

125.ll!#RE9EA2 DIS

, 4.7.7 Each snubber 8 shall be demonstrated OPERAli2 by the requirements i

I of the fallowing surveillance prograss and pursuant to require-seats of Specificaties 4.0.5. }

4.7.7.1 Visual fospecties Prearse f

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1 Engineering evaluaties is not required when a snubber is renewed for

! surveillance testing provided it is returned to OffRA8!.E status withis I the requirements of action statenest a. l' 1

l 8 Safety related saubbers are listed in the latest revisten of applicable

! surveillance test precedure(s). Saubbers may be added to, or removed l j f roe, safety related systees and their assigned groups without te6ee en f

i,1ces Amendeest.

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DAVIS SESSE, IMIT 1 3/4 7 20 ggg g, g4 4 1

Dock:st No. 50-346 1.icen;3 No. NPF-3 S3rici No. 1346 P!.W SYSTT.95 -

f, 05%'UMMEIlMISC311LUGIM -

a. General Requirements At least once per inspection interval, each group of soubbers in use in the plant shall be visually inspected in accordance with Spectfication 4.7.7.1.b and 4.7.7.1.c.

Visual inspections may be performed with binoculars, or other visual support devices, for those snubbers that are' difficult to access and where required to keep espesure as low ~as reasonably achievable. Response to fa!!ures shall be in accordance with Specification 4.7.7.1.d.

b. Taspection Interval and Sample Criteria The inspectton interval and sample criteria say be applied on the basis of snubber groups. The soubber groups may be established based on physical characteristics and accessi-bstity. Isaccessible soubbers are defined as those locat.

ed: (a) inside contairaent, (b) in high radiation exposure zones, or (c) in areas shere accessibility is tietted by physical constralsts such as the need for scaffolding.

Visual inspections for a group shall be performed in accordance with the following schedule:

Saubbers are divided into four (4) groups " Accessible" -

Group I and "!naccessible" Group !! for either hydraulic or sechanical.

No. of !aoperable Soubbers nlithin a Group - Subsequent Group Visual per Inspection laterval faspection Intervat 3 * ,8 0 18 months

.I 12 monthe 2 6 month:

3, 4 124 days

$, 6, 7 62 days 4 or more 31 days the tospections for a group shall teclude 100 percent of soubbers la that group.

I Ihe inspection interval shall not be lengthened more than one step at a tilse, and The provisions of Spectitcation 4.0.2 are not applicable.

'All the time intervals are 12$1, eacept that the inspection of inaccessible saubbers may be deferred to the nest shutdous when plaat conditions allow $ days for inspectica.

DAVIS 8ES$t, W!! ! 3/4 7 21 Anendment No. 94-

\ uvaut.bo. su-> u I

Licenza No. NPF-3 Serial N6.13bv!

P SYSTD'S .

M4MQ!11gVIS (Ntim4)

c. Acceptance Criteria A snubber shall be considered OPERABLI as a result of a visual inspection ift (1) there are no visible indications

! of damage or inoperability, and (2) attachments to the '

foundation or supporting structure are secure.

d. Response to Tailures_

for each soubber unit which does oor, meet the visual inspection acceptance criteria of Specification 4.7.7.1.c:

Detensine the snubber OPERABI.E by functionally testing the snubber per Specification 4.7.7.2, unless the (Lydraulic) soubber was determined inoperable because the fluid port was found uncovered; O ,

f 1. Perfora the ACT!0N specified in 3.1.Ta; g

2. Perfone an engineering evaluation as specified in j 3.1.7.b.i I

.gd a

3. Increase the frequency of group inspection as de-scribed in Specification 4.7.7.1.b unless the cause of the rejection is clearly established and resedied for that particular snubber and for other snubbers that say be generically susceptible.

e. "Inse.ri W 4.7.7.2 Functional Test Protrae ,

a. Ceneral Requirements.

At least once per laspection interval a representative saepte of each group of saubber to use in the Plant shall be functionally tested in accordance with Specifications 4.7.7.2.b and 4.7.7.2.c. Ilesponse to the failures shall be in accordance with Specification 4.7.7.2.d.

For all snubbers, functicast testing shall consist of either beach tasting or toplace testing.

b. lospectico Interval and $4epte Criter a The snubbers say be categorized inte groups based en physical characteristics. Snubbers are divided inte four (4) groups: " Accessible" Croup 1 and "tasccessible" -

Group 11 for either hydraulic or mechanical, tack group say be tested tadependently free the standpotat of per=

forming additional tests if fattures are discovered, i

DAVIS lES$t, WIT 1 3/4 7*22 Amendment No. Q ,94

Docket No. 50-346

, Lican23,No. NPF-3 Satici No. 1346 .

I Insert "A" Transient Event Inspection An inspection shall be performed of all hydraulic and mechanical snubbers ,

attached to sections of systems that have experienced unexpteted, potentially damaging transients as determined from a review of operational data. A i visual inspection of the snubbers on these systems shall be performed within six 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.

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[Joc au t ,,ho . JU-J40 Licenza No. NPF-3 S2ri5l Nb. 13hy sysitns -

SMTllL$1CEJJay1ReMNTS (continuedi The inspection interval for functional testing shall be 18 months.

Snubbers which are scheduled for removal for seat mainte-nance say be included in the test sample prior to any maintenance on the snubber.

The representative sample shall consist of at least to percent (rounded off to next highest integer) of each group of snubbers in use in the Plant. The selection process shall ensure that all snubbers, regardless+of their accessibili- l ty classification, are functionally tested at least once every ten inspection intervals,

c. Acceptance Criteria for hydraulic snubbers (either inplace testing or bench testing), the test shall verify that:

l. Snubber piston will allow the hydraulic fluid to

, " bypass" free one side of the piston to the other to assure unrestrained action is achieved within the specified range of velocity or acceleration in both tension and compression.

2. When the snubber is subjected to a movement which creates a load condition that exceeds the specified range of velocity or acceleration, the hydraulic fluid is trapped in one end of the snubber causing suppres-sion of that sovement.

3. Snubber release rate or bleed rate, where required, occurs in compression and tension.

For mechanical snubber in place and bench testing, the test shall verify that:

1. The force that initiates free movement of the snubber rod in either tension or compression is less than the specified maximum drag force.

1

2. Activation (restraining action) is achieved in both tensionandcompressioy wA:n Ae spec $cJ roop 8

P:=::::t--et-ethe. m_,,,iens4.e f.eetien;! testing fer iedisids1 -

savhbees-in-these-eetetecie; ;;;y be g;;ated by tt.e 0 issi;; ;;17 i f-a 5 eti m .1: b:ei: fer ::c.p i:: i: ;;;;;;; d.

DAVIS-BESSE, UNIT 1 , 3/4 7-23 Amendment No. H , 94

Dqc ke t .5k) . 50-346 Licsn;3 No. NPF-3 s

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rimi N'o. 1346 . - - .'i r; I PLA.YT SYSTEMS -

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. . il d t, . _ . , 1 SilHYEl'.I.L C' JIMIEf.I'ENIS_ffontinue f1, , ; . , ,; '

4. Response to Failures For each inoperable snubber per Specification 4.7.7.2.c:

1. Perform the ACTIONS specified in 3.7.74 and 3.7.7b; and

2. Within the s'pecified inspection interval, functionally test an additional sample of at least to percent of the snubber units from the group that the inoperable snubber unit is in.

The functional testing of an additional sample of at least 10 percent from the inoperable snubber's group is required for each snubber unit determined to be inoperable in subsequent functional tests, or until all snubbers in that group have been tested; and

3. The cause of snubber failure vill be evaluated and, if caused by a manufacturing or design deficiency, all snubbers of the same or similar design subject to the same defect shall be functionally tested within

, 90 days from determining snubber inoperability. This testing requirement shall be independent of the requirements,in 4.7.7.2.d(2) above.

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l 1 DAVIS-BESSE, UNIT 1 3/4 7-24 Amendment No. 1),94 (Tables 3.7-3 and 4.7 4 deleted.

_ _ _ _ _ . - _ _ _ . _ - DrR mrn 1& M\ _LKW ____-_-__-

Docket.N.o. au-ho i Licensa No. NPF-3 Sarial N'o. 1346 PLOT SYSTEMS BASES PLWT SYSTEMS 3/4.7.7 SNUB 8ERS

! BASES A11' safety-related snubbers are required OPERABl.E to ensure that the

1. structural related systems integrity of the reactor is maintained duringcoolant and following systesa anglgother 5 safety-

__. event.

e are, those installed on l Snubbers safety-related excluded systems for from loads thisother inspection than progegJMY or on nonsafety-related systems and then only if their failure or failure of the system on g which they are ig" stalled, vould have no adverse effect on any safety-related system during a . . W.S event. l

Inoperable is defined as

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1. For visual test -

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a. The fluid no long' er is supplied to the valve block, or

b. Mounting pins are disengaged from the saubber.

c. Attachment to foundation or supporting structure is not secure.

2. For functional test .

a. The snubber (excluding end anchors, i.e., pin-to pia) does not

, meet specified test criteria.

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The visual inspection frequency is based upon maintaining a constant level of snubber protection to systems. Therefore, the required inspection i

I interval varies inversely with the observed snubber failures and is '

determined by the number of inoperable saubbers found during an inspec-j tion.

Inspections performed before that interval has elapsed say be used i as a new reference point to determine the next inspection. However, the results of such early inspections performed before the original required '

time interval has elapsed (noeinal time less 257) may not be used to lengthen the required inspection interval. Any inspection whose results

! require a shorter inspection interval will override the previous schedule.

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Wen the cause of the rejection of a snubber is clearly established and remedied for that snubber and for any other snubbers (Tat say be generi-cally susceptible, and verified by functional testing, that saubber may be exempted free being counted as inoperable. Generically susceptible snubbers are those which are of a specific make or model and have the same design features directly related to rejection of the soubber by visual inspection, or are similsely located or exposed to the same environeestal conditions such as temperature, radiation, and vibration.

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j DAVIS-8 ESSE, UNIT 1 B 3/4 7 ,

Amendment No. 94

- - - _ ~ - , , ~ . - . - - - - , - - - - - - ...-,----ns.-...,---.--- . . - - - . - . - - - - - - - - , - . - - - - - ~ - - , , , - . , . . - . . - , . - - - . - - - , . - - - , - - - - - - . , - ,

1 Oucket .S o . JU-Jau- 1 Licznsa No. NPF-3 .fj f ,. , * .

. . . , , , ,  ; {l Sarial No. 1346 PLANT SYSTI.MS 5<; - . \

I O 9 '. ' ..  ; .....  :,,;c;d I SASES l Uben a snubber is found inoperable through a visual or functional test, an engineering evaluation is performed, in addition to the determination of the snubber mode of failure, in order to determine if any safety-related component or system has been adversely affected by the inoperability of the snubber. The engineering evaluation shall determine whether or not the snubber mode of failure has imparted a significant effect or degrada-tion on the supported- component or system.

To provide assurance of snubber functional reliability, a representative sample of the installed snubbers will be functionally tested at 18 month inte rvals . Observed failures of these sample snubbers shall require functional testing of additiocal units. When a snubber is found to be inoperable due to failure to lock up or failure to move (i.e., f rozen in place), the cause will be evaluated for further action or testing.

In cases where the cause of failure bas been identified, additional snubbers that have a high probability for the same type of failure or are being used in the same application that caused the failure shall be tested. This requirement increases the probability of locating inoperable snubbers without testing 100% of the snubbers.

Hydraulic snubbers and mechanical snubbers may each be treated as a dif ferent entity for the ab'ove surveillance programs.

i DAVIS-BESSE, UNIT 1 8 3/4 7-$a Amendment No. 94

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LICENSE AMEN 0 MENT 055293 012887 150.00 150.00 Ord.Cr CATE 40 vtecOs rati'i TOTAL AMOUNT

>S- 540642 020687 873800 UNITED STATES NUCLEAR _ 15_0. 0_0

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540642 TOLEDO TRUSTCORP 70'.tDO u ANSFELD. CP*O VOD AFTER 90 DAv5 NCf VA.c pot MO8t THAN 5:5 000 UP4E55 COUNTER 5GC PAY To rm ci:t- :s _ _ _ DA.TE . AMOUNT-UNITED STATES NUCLE AR _02/.06/87 $********150.00 REGULATORY COMMISSICN OFFICE OF THE CONTRCLLER WASHINGTON OC 20555

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