ML17139A730

Forwards Info in Response to NUREG-0737,Item II.E.4.2 Re Containment Vent & Purge Valves.Several Valves Do Not Meet Required Closing Time.Investigation Underway.Info Closes SER Item 84

ML17139A730
Person / Time
Site:	Susquehanna
Issue date:	06/10/1982
From:	Curtis N PENNSYLVANIA POWER & LIGHT CO.
To:	Schwencer A Office of Nuclear Reactor Regulation
Shared Package
ML17139A731	List: ML17139A730 ML18031A357 ML18031A359 ML18031A360
References
RTR-NUREG-0737, RTR-NUREG-737, TASK-2.E.4.2, TASK-TM ER-100450, PLA-1111, NUDOCS 8206160242
Download: ML17139A730 (15)

Text

REGULATORY I RMATION DISTRIBUTION SYS (RIDS)

'AOCESSION NBR:8206160242 DOC ~ DATE: 82/06/10 NOTARIZED: NO DOCKET FACIL:50"387 Susquehanna 'Steam Electric Station< Unit 1i Pennsylva 05000387 50-388 Susquehanna Steam "Electric Stations Unit 2< Pennsylva 05000388 AUTH'AME AUTHOR AFFILIATION CURTIS' ~ N ~ Pennsylvania Power 4 Light Co+

RHC IP. NaME RECIPIENT AFF ILIATION SCHNENCERgA ~ Licensing Branch "2

SUBJECT:

Forwards info in response to NUREG 073?iItem II.E.0,2 re containment vent 6purge valves'everal valves.do not yeet required closing time. Investigation underway. Info closes 'SER Item 80.

DISTRIBUTION CODE: A046S>>COPIES RECEIVED:LTR g ENCL Q SIZE TITLE: Response to NUREG '"0737/NUREG 0660 TMI Action Plan Rgmts (OL's)

NOTiES ~

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL LIC BR ¹2 BC 01 -7 7 INTERNAL; ELD/HOSP 1 0 IE/DEP, DIR 33 1 1 IE/DEP EPDS 1 1 IE/OEP/EPLB 3 3 NRR/DE D IR 21 1 1 NRR/OE/ADCSE 22 1 1 NRR/DE/ADMQE 23 1 1 NRR/DHFS OIR 28 1 1 NRR/OHFS/DEPY29 1 NRR/DL,OIR 19 1 1 NRR/OL/ADL 16 1- 1 'NRR/DL/ADOR 15 1 1 NRR/OL/AOSA 17 1 1 NRR/OL/ORAB 18 3 3 NRR/OSI DIR 2Q 1 1 NRR/DSI/ADDPS25 1 1 NRR/DSI/ADRP 26 1 1 NRR/DSI/ADRS 27 1 1 NRR/DS I/AEB 1 1 NRR/DS I/ET'SB 1 1 NRR/DSI/RAB 1 1 NRR/DST D IR 30 1 1 AOGP 31 1 NRR/DST/AOT 32 1 1 EG FILE 00 1 1 RGN1 1 1 EXTERNAL: ACRS '34 10 10 FEMA REP DIV 1 I'NPOpJ ~ STARNES 1 LPDR 03 '2 2 NRC PDR 02 1 1 NSIC 05 1 1 NTIS 1 1

'TOTAL NUMBER OF COPIES REQUIRED LTTR 54 ENCL 53

lP 0

P A Aj N

~ 'I S,l I ]t' q ~ I f 1

Pennsylvania Power 8 Light Company Two North Ninth Street ~ Allentown, PA 18101 ~ 215 / 7705151 Norman W. Curtis Vice President-Engineering 8 Construction-Nuclear 215/ 770-5381 JUN 10 1982 Mr. A. Schwencer, Chief Licensing Branch No. 2 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 SUSQUEHANNA STEAM ELECTRIC STATION QUALIFICATION DOCUMENTATION FOR CONTAINMENT VENT AND PURGE VALVES ER 100450 FILE 841-12 Docket Nos. 50-387 PLA-1111 50-388

Dear Mr. Schwencer:

The enclosed documentation is provided in response to NUREG-0737, item II.E.4.2, part 6. We have committed to provide the enclosed documentation to substantiate that the con'tainment vent and purge isolation valves meet the interim qualification criteria to close within the technical specification limits.

This documentation completes our commitment and will allow closeout of item II.E .4.2 and SER open item number 84.

A complication has been found during testing of these valves. Several valves do not meet the required closing time. An investigation is currently underway to resolve this problem. We plan to correct the deficiency prior to fuel load or limit the valve open position to assure compliance with the technical specifications. If you have questions, please feel free to contact me.

Very truly yours, N. W. Curtis Vice President-Engineering 6 Construction-Nuclear DPM/mks cc: R. Perch 8206i60242 8206i0 PDR ADOCK 05000387 ~ i.'

PDR

TELE XE 312.844~ . TELIC 720424

[PRATT HENRY PHATT COMPAl. 4Y

( l '. <<ll iX'i <'ll<>'il)( ('l ill<> i'()I i'iili(1 ~X'~i('l}7H 401 SOLTH HIGHLANDS'Ei~E . AURORAe ILLINOIS 60507 May 20, 1982 Bechtel Power Corporation Fifty Beale Street P. 0. Box 3695 San Francisco, Calif. 94119 Attn; E. B. Poser Subj: Susquehanna Purge valve analysis Your P. 0. 8856-P-31-AC Pratt Order No. D-34933 Gentlemen:

In response to your May 7, 1982 letter to Mr. R. Nelson, we offer the following:

l. Yes, the reports furnished for Susquehanna are very similar in format and content to those previously performed for other plants (and furnished to the NRC)..

2 6 3~ P in the bearing friction torque calculation represents hP, the differential pressure across the disc at any given disc angle as calculated during the LOCA flow event. Upstream pressure considers the pressure-time (drywell) curve furnished.

U, the sleeve bearing coefficient of friction equals

.25 for the bronze bearings furnished. This value identified in the appendix to A%PA C-504-80 (copy is attached for your reference) and is considered to be a higher value than typically expected in service.

However, for the sake of conservatism, Pratt has identified bearing friction torque in the reports but has not actually incorporated its value in our shaft stress calculations. That is, the highest stressed section of the shaft is the top stub shaft between the top bearing and the disc, and that section sees the maximum fluid dynamic torque minus the top bearing friction torque. In your reports we have used the dynamic torque value alone.

~ se eo roe AIllStBd

~ NO1I ~ T1 ~ 8

~

Bechtel Power Corp.

May 20, 1982 page The basis for our fluid dynamic torque calculation

.and our statement that maximum dynamic torque occurs when initial sonic flow occurs coincident with 68o-72o disc angles is as follows:

3 TD= CTD hP is the common equation used for dynamic torque calculations for flow through a butterfly valve (again reference the appendix to AWWA C-504-80). In order for Pratt to evaluate our empirical data we began plotting CT, torque coefficient vs P2/P , pressure ratio, on log-log paper. What we learned is tlat when CT above is substituted by C 2, where C' C hP/P2 then the resultant curves are upward an5 dowKward straight lines peaked at the critical sonic pressure ratio. The highest peaks were obtained at 68o for. asymmetric disc models and 72o for symmetric discs. Therefore, it convenience in plotting that we have elected to express is for this our torque equation on this absolute downstream pressure basis.

6. The 19-7 psia backpressure condition was an earlier assumption made by Pratt as a typical downstream pressure. In your reports, this assumption was not used as Pratt could not qualify its value. Instead, the downstream pressure was selected by considering the valve closure time and pressure-time curves furnished, such that the downstream pressure at 68o would yield the critical ratio for the air-steam mixture. This is considered to be the worst case approach.

7a. The steam/air mixture with 1.4 lbs. steam per 1 lb. of air

.was an assumption made by Pratt as a typical condition.

Variations on this mass ratio do not have significant impact on torques.

7b. The seating factor is the coefficient of seating or unseating torque as per the appendix of AWWA C-504.

by tests in our lab.

It is determined 7c ~ The outlet pressure (P ) refers to the new value of down-stream pressure identified in response number 6 above.

7d. Flow as well as 'torque coefficients were determined by Pratt in our model testing. The values of mass flow rates presented are intended as reference data for approximate information only.

~ ee AlllAd ot.ao INOV ~ TSI

~~

1 Bechtel Power Corporation May 20, 1982 page 7e. Hub seal torque refers to the frictional torque at the disc hub to body interface on certain on-center disc designs previously used. The model 1200 valves analyzed do not have hub seals and this value does not apply.

7f. In the Susquehanna valves analyzed, Pratt has'considered the effect of a 90 elbow, out of plane with respect to the valve shaft, immediately .upstream of the valve as the worst case approach. -This elbow effect is folded into the torque coefficients used.

8. The starting, or delay, times were defined by >echtel as a minimum of .1 second and a maximum of 5 seconds. The .2 second figure used for the 6" valve appears to be uncon-servative as the maximum delay time would have resulted in a higher upstream pressure. However, maximum dynamic torque for that size valve is so low that it appears that the the variance in starting times will not adversely affect the conclusions made in that report.

The 30 second, 17 second, and 2.8 second closing times were selected from our assembly and test reports which have recorded actual closing times for those valves as measured in our shop under no-flow conditions. They are not the minimum possible times and do not relate to duct pressure.

They represent, the only known times that Pratt could confirm as the original order did not specify opening or closing times.

9. The appropriate closing times should be determined by the owner. Ne can and do hereby state that controls on the actuators are revised such that a valve if the pneumatic closing time of 5 seconds or less is achieved, that the result of the reports furnished for Susquehanna will not be adversely effected.

He trust this information will be satisfactory to your needs.

Very truly yours,

Manager, Contract 6 Proposal Engineering TJW:pst Attach" A. K. Nilson

'C:

R, D, Nelson SLIAStBd

,R. N. Kaza ~ <<e oo ~ >so IIOOQOt1I ~ ~

12 BUBBER.SEATILD BUTTI!Bl I.Y VALVES AI'I'ENI)IX 13 "

The upper surface of the valve disc may make special provisions to pre- 4 Section 6-Mariting and Shipping shall bc visible and shall hc covered vent leakage past the seats. No part Sec. 6.1 Marking them for shipinent so that no damage with a pool of water at 0 psi pressure. of the valve or disc shall be perma-owing to the manufacturer's negli-The length of test shall bc at least 5 nently deformed by the test. It is the hfarkings for otlier than wafer gence will occur in handling or transit.

min., and there shall lie no indication purpow of this section t<i provide valves sliall lie cast on the Iio<ly or All caviti<s shall lie drained of water.

of leakage past the valve disc (visible evidciice of the adequacy of each basic shall lie on cast plates with rais<~i Valves larger tlian 36 in. in size shall in the form of bubbles in the water type offered by a manufacturer to letters attached to the valve liody. lie lwilted or otherwise fastened to pool on top of the disc) during the perform under design pressures within The markings shall show Ihe valve ski<Is in such a manner as to preclu<le test period. As an alternative to this the applicable rating for a sufficient size, manufacturer, class, and year of damage in subsequent haiidling. All test procedure, Class 150A or 1508 number of operations simulating a manufacture. The minimum size of unpainted steel- and iron.niacliinc<l valves may be given a 150.psi hydro- full service life. The adequacy is to letters shall be l in. for valves 3-12 surfaces shall be coated with a pro-static test. During the test, the valves be proved by tests, made on valves in. in diameter and f in. for valves tective slushing conipound. I ull.face shall be droptight. selected to represent each basic type larger than 12 in. in diameter. Cor- Range protectors of waterproof ply-of seat design of a size within each rosion-resistant plates attached to the wood or weather-rcsistant pressboard, applicable group in Table 6 and in a body and with }-in. etched or en- of a least the diameter of the Range Sec. 5.4 Hydrostatic Teat pressure class or classes equal to or graved letters may be used for mark- Oil, shall be fastened to each llange All valve bodies shall be subjected ing wafer valves. to protect lioth it and the valve to an internal hydrostatic pressure TABLE 6 interior. Small valves may lie fully equivalent to two times the specified Sec. 64 Shlpplng 7'stt Cydst Rc<p<iral packaged at the manufacturer's op-shutoff pressure. During the hydro- Valves shall be complete in all tion. Components shipped unattached static test, there shall lie no leakage No d Csdie respects when shipped. The manu- shall be adequately protected and through the metal, the end joints or facturer shall use care in preparing identified for correct field assembly.

the shaft seal, nor shall any part be permanently deformed. The time duration of the hydrostatic test shall 3-20 2I-I2 IS-72 I0,000 1,000 0 'PPENMX be sufficicnt to allow visual examina- Method for Calculating Torques Required tion for leakage and shall be at least to Operate ButterQy Valves min. for valves 8 in. and smaller. greater than the valves being pur-1 chased. ~ The required number of This apprwdi>> is for lw/orw<otlow owly aat is wol a port o/ rfIVII'A CSOf.

3 min. for valves 10 in. through 20 cycles appears in Table 6. Every in. and 10 min. for valves 24 in. and cycle shall consist of applying the rubber seat friction when the valve larger. The following factors affect the differcntial pressure to the disc in the disc is being seated or. unseated.

closed position, then opening the valve torque required to operate rubber- 2. Boaring friclion Iorqt<o. This is Sec. 5.5 Proofs-Desiga Tests (which will relieve the pressure) to the seated butterfly valves:

the torque required to overcome the wide-open position and then closing friction between the v<<ive shaft and Upon request, the manufacturer the disc. The valve shall be drop-

l. Valve diaineter shall furnish certified copies of the 2. Shaft diameter the shaft bearings.

tight under the rated pressure dif- 3. Bearing friction coelhcie<<t 3. Dynamic lorq<<o. This is the reports covering the tests. One proto- ferntial upon completion of the cycle type valve of each size and class of

4. Type ol seat and seat material torque developed by the disc on the test. 5. Shutoff pressure valve shaft because of the difference a manufacturer's design shall be 6. Velocity hydrostatically tested with twice the in pressures that exist across thc faces

7. Type of disc of the disc as a result of Row.

specified shutoff pressure applied to Sec. 5.6 Relectloiz 8. System head characteristics one side of the disc and zero pressure 4. Hydroslalic lorq<<c. This is the

9. Piping arrangement on the other side. The test is to be Any butterfly valve or part that torque caused by the diR'erence in made in each direction across the the inspector may condemn as not static head of water on the valve disc These factors combine to make up disc, and, in the case of Ranged conforming to the requirements of above and below the valve shaft when the following four classes of torques the shaft is horizontal. It is added to valves, the v'alve body shall bc this standard shall be made sa'tis-factory or shall be rejected and 1. Scaling or t<nssaling lorqt<c. This or subtracted from the seating or un-bolted to a flanged test head. Under replaced. is the torque tequired to overcome the seating torque.

the hydrostatic test, the manufacturer

14 RIIIIlllIt SRATRI) IIUTTI III:I.Y VAI.VI:.8 AI I I. It I)Ib 15 Operator torques can be calcu1ated using the following formulas:

Te ~ (Ts +

T, a (1.2 7'e + Ts)

Ts + Ts)

(6)

(7)

A ol reservoir, and (2) where the elevation the energy gradient is variable, de-such that head loss varies as the square of the velocity and the head T, Cef)s (1) pending on flow, as in the case ol a source is a constant elevation, a Cc 7's ~ 4 71 f Ec d P (2)

Equation 6 is solved by using the i centrifugal puinp. Jt should be noted value of 22 with valve fullyopen, and maximmn prcssure drop across the that all heads arc measured to energy a C, value o(85 Ts Csf)e P (3) valve with the disc in tlic c1oscd posi c gradients and thcrcfore must include

~ Problcsstt EVhat is the maximum V

Ts CrVP a

~ 3.06 f)c e

O.TSSf)e (4)

(5) tion; Eq 7 must bc solved succcssivcly for several values of vc1ocity to deter-mine the maxiinum combination ol dynamic and bearing torques. The velocity head, if any. Thc ordinate difference between tlie head source curve (or line) and the system head curve represents thc total head loss operator torque?

Solttfiottl The velocity and pressure drop with the valve fullyopen will be:

in which: head loss that will occur across tile valve for each value of velocity can (tota1 dynaniic head) across the valve at any velocity; therefore, the pres.

254 0.785 X 4 5t

- Ps T, ea seating or unseating torque, only bc determined by considering the sure drop across the valve correspond-in foot-pounds of the entire system. 'ydraulics ing to each value ol velocity can be P ea

/16%a ea 0.53 psi (Eq 5)

Ts ea bearing pounds torque, in foot- Figure A 1 illustrates a graphic determined and tabulated. ( )

(CJ method of determining the pressure The coeflicient, Cs, corresponding Td ~ dynamic torque, in foot- drop across a valve lor any velocity Because head loss varies as the square to each value of velocity can be cal-pounds between the valvewpen and closed culated by means of Eq 5, and the of the velocity and the head source is Ta ~ hydrostatic torque, in loot- position for two typical conditions: a constant elevation, the pressure corresponding coefficient, Cs, deter-poiinds (1) where the elevation ol the energy mined by using thc valve character- drop across the valve corresponding Q ae flow, in cubic feet per second gradient at the source of supply is istic curves showing the relationship to any velocity will be:

V ac velocity, in feet per second constant, as in the case of a large of Cc, Cs, and disc angle. Thc dy- 0.53) Vt D ~ diameter of valve, in feet namic torque, Td, and the correspond-(25 d ~ diameter ol shaft, in inches ing bearing torque, Ts, can then be 16t P ~ pressure drop across valve, calculated using Eq 3 and 2, respec- . ~ 25 0.0956 Vt in pounds pcr square inch tively.

oC, ~ coeflicient ol seating or un- Heed loss Iveiso Wde Osee) The following is an example illus- For any pressure drop across the seating torque trating thc method for calculating the valve, the bearing torque will be:

~ oCs ea coefficient ofdynaniic torque operating torque required for a valve. Te ae 4.71 Cs ac coeflicient ol flow Girctt: A 54-in. valve, a maximum X 4.5' 4.875 X 0.25 P (Eq 2).

f ~ bearing friction coefficient discharge rate, Q, with the valve full (usually assumed to be 0.25 X open, of 254 cfs, a maximum shutoff lor metal bearings) pressure across the valve of 25 psi, a Ts ~ 116.2P shaft diameter of 4$ in., valve shaft The required operator torque, T is a horixonta1, a system characteristic TabIe Al gives the various factors determined from the higher value Ssslea iieed loss I given by the two formulas:t uscsevoa oi teesss Csedacs Reosdsed ei TABLE Al SooNe So Sceadeia Veiecdr S) Factors fssdirotsd for Vsloritiss al l.ft lsstsesols Frost Sfaziauas Velocity The relationship of Ce, Cr. and disc angle Ssssea Heed loss varies depending upon the shape ol the disc Sleeeeea Vcsesor nea Srehe acde Ossa) and how it is mounted on the shaft. 'Char Y acteristic curves showing this relalionthip Decaa Ise p re and lhc value ol C, may be obtained from the Ce t4re re~i.tre osl Jtdt valve manufacturer. The values ol these vs loess I t) coetfscients should not be applied indiscsimi- Flg. kl. Bslattost Between Velodty and 16 0.53 22.00 naidy when calculating torque sequiremerits Psessate T)sop tn Buttetdy Valves 1$ 3.49 S.03 15.12 4,509 4ST $ ,296 for operation ol valves produced by another 14 6.26 5.59 9.36 $ ,339 873 6,'212 malsufaclusef. Tlr lfpars ittssstrotss a proPlic nsrtlod for d.d4 437 7.49 6,034 1,233 7,267 f Use lhe plus value for Td <<ben calculating *tsesiisiap prrssssrr efrosss across a t>>fos 11.23 3.5S 6.19 6,334 1,566 7,900 opening torque and lhe negative value <<ben sssssfsr tls tts>> conditiosss cfrscnbrd fss tbs 11 13.43 $ 33 6/23 l,d73 S,396 caksdating dosing torque., kst. 10 1$ .44 4.ld S,SSI 2.1$ 3 S,034 4 ~

Beohtel Power Corporation Enginoere-Coretructors

)H RKPI.Y PNASI RE4

"'i0 scale Street IU 166SO San <<enceco. Cetifornla Mell Iddreeer PO. 8ox 3M5, San Francisco, CA 94419 y;..( x "20167255 NCo Ti Ma Crimninsg Jr,

~ Pennsylvania Brwer and Light catpany P 0. Box 1870 Allentown, Pennsylvania 18105 Attention! W. Rhodes Sub)ect: Susquehanna Steam Electric Station Qrd.ts 1 and 2 Job 8856 Containnent e Valve Anal is The following is a axaplete reply to your letter No. PLB-14202 dated Merch Z9> 1982, our corresponding DocNttent Contxol No. '162703.

This is to advise you of the status of the ccntaimrant purge valve operability analysis by Henry Pratt Co. (P.O. 8856-P-31).

Ne have reviewed the reports subttitted by Pratt for the three valve si2es. These reports indicate that the valves are qualified for the .

closure tines contained in the Techical Specification to meet the MRC's interim position. Gctttments have been generated for Pratt's resolution. The amnents are clarifying/explanatory & nature intended to provide a nnre complete report and do not identify any eries in the subtd.tted material. ln a discussion with Pratt, we understand that Pratt has discussed, in a general manner, the bases for their torque calculations and that reports of a similar fovnat and level of detail have been prepared for other utilities and suhnitted, apparently successfully< to the NRC. On the basis of the above, we have no reason to believe that the reports are unacceptable and do not believe that the resolution of the amounts is necessary prior to suhnittal to the NBC to close out the SER open item.

Pratt's responses to the eeaeents are to be telempied to us by May'21.

Copies of the reports have been transmitted previously to your J, Agnew.

Ocetaf.went Pmqe Valve Analysis fig Corporation Paae 2 Bechtellower t:.;.f @ "20l67255

%e are currently investigatin9 the modifications required in order for the valves, to be fully qualified (i.e., 5 second closure t~)<

which is required hy the first refueling outage.

We wQl keep you closely infaaned of the status of this issue.

Very truly yours<

E. B. Poser project Engineer

,Written Response Req'd! No JB/(Ã)/cas cc: J, Agnew (PAL)

bcc: R. Parekh J. Saame D. Crosby A. Daily ID 7 '02016 581 7 Henry Pratt Qxpany 401 South Highland Avenue Aurora, Illinois 60507 Attention: Mr. R. Nelson

Subject:

Susquehanna Stean Electric Station Units 1 and 2 Job 8856 Contairxnent Isolatio+Purge Valve Anal is P.O. 8856-P-31-AC Gentlemen:

Ne have reviewed the subject analysis and have. the following canments which are generic to all three size valves.

Has the torque calculation m thod in the Henry Pratt's analysis been applied in the same form to other plants (in addition to SSES) 2

2. &at does the pressure differential, P, in the bearing friction torque calculations exactly stand for2 In. other mrds, what are the locations which are selected to determine this pressure differential? How are the pressure at these selected locations calculated fran the drywell pressures time history?

3. Also in the bearing friction torque calculation, what is the physical significance of U, designated in the Henry Pratt's analysis as bearing coefficient of friction? Nhat is its value? Has the expressioin of this quantity been verified against any aeasurerent? If yes, please provide references.

4. Por the fluid dynanic torque calculation, please provide references which delineate the analytical background of the hy9rodynanic torque equations and their canpatibility with measurements.

5. Please explain the arguments behind the conclusive statement on page 5 in the Henry Pratt analysis that says that "the maximum dynanic torque occurs when initial sonic flow occurs coincident with a disc angle of 72'symmetric) or 68 (asynmetrxc) fran the fully closed position."

R. Nelson

6. $ hat is the justification for stipulating that backpressure of 19.7-psia can be assed through out valve closing cycle?

Has this stipulation used in the analysis?

7. In the computer output, scae of the quantities are either not clear or not mll-defined. Specifically, 7-a. Is the mass ratio of saturated stean to air which equals 1.4 to 1 an assunption?

7-b. Mat is the aeaning of seating factor which has the value of 15?

7-c. Mat does the outlet pressure (P 6) refer to?

7-d. How does the Henry Pratt's analysis determine the mass flow rates, CB4 and S(XÃ?

7-e. Shat does the hA seal torque mean? Hmr is it determined?

7-f. How are the effects of elbows close to the valve accounted for?

8. 9he starting times for the analysis are 5 seconds for both the 24" and 18" valves but is 0.2 second for the 6" valve. Please explain the reasons for the difference in the starting times.

'3he closure tines appear to be 30 seconds, 17 seconds and 2.8 seconds for the 24" < 18" and 6" valve sizes, respectively.

Aee these the minima possible closure times? Do these closure times depend on the pressure in the duct?

R. Nelson gg 7'0201658

9. Please include in each Conclusion Section the appropriate closing tim s of the valves. Also include a statement to the effect that by changing the solenoid valve on the operator so that the valves close in less than 5 seconds, that the fast closure of the valve will not effect the result of the reports.

Very truly yours,.

E. B. Poser Project Engineer Written Response Required: Yes Date Due: Nay 14, 1982 Fuel Zaad Impact: Yes JS/MD:sla

~ cc: E. W. bhad . (PT) Grp. Resp.

Coda PE51/4-2 Orlo.

Gr . Ldr.

Gr . Su vr.