ML20154A429

From kanterella
Jump to navigation Jump to search
Responds to NRC 880404 Request for Addl Info Supporting Util 861002 & 870312 Responses to IE Bulletin 85-003, Motor- Operated Valve Common Mode Failures During Plant Transients Due to Improper Switch Settings. Program Description Encl
ML20154A429
Person / Time
Site: Hatch  Southern Nuclear icon.png
Issue date: 05/04/1988
From: Mcdonald R
GEORGIA POWER CO.
To:
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
IEB-85-003, IEB-85-3, SL-4431C, NUDOCS 8805160001
Download: ML20154A429 (17)


Text

<

,o Georgia Power t ,ec o ,. o ,p vi m nt SL-4431c 1995C X7GJ17-H110 May 4, 1988 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Hashington, D. C. 20555 PLANT HATCH - UNITS 1, 2 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 REQUEST FOR ADDITIONAL INFORMATION ON ILJLILLETIN 85-03 Gentlemen:

By letters dated October 2, 1986, and March 12, 1987 Georgia Power Company (GPC) submitted its response to IE Bulletin (IEB) 85-03, "Motor-Operated Valve Common Mode Failures During Plant Transients Due to Improper Switch Settings," for Plant Hatch Units 1 and 2. On April 4, 1988, the NRC transmitted a request for additional information (RFAI) on GPC's IEB 85-03 program. Our responses are contained in Enclosure 1, and a detailed program description is contained in Enclosure 2.

During the recently completed Unit 2 Refueling / Maintenance outage, GPC completed static HOV testing on all the applicable High Pressure Coolant Injection (HPCI) and Reactor Core Isolation Cooling (RCIC) valves. (High delta pressure tests are planned.) Per the bulletin requirements, GPC had planned to submit a written request within 60 days of completion of the Unit 2 program. However, as a result of the RFAI, GPC is providing this interim submittal. In addition, GDC would like to schedule a meeting with appropriate NRC and Region II personnel to discuss the details of our program. As you know, we have elected to use a Motor Actuator Characterizer (MAC) system from Limitorque for signature analysis rather than the Motor-Operated Valve Actuation Testing System (HOVATS). Additionally the torque switch settings have been determined utilizing the Limitorque valve equations. GPC realizes that the NRC may be more familiar with MOVATS, and a discussion of our experience with the limitorque equipment and methodology can be included in the meeting agenda,

'f8 I\

i

~eso5160001 880504 \

PDR ADOCK 05000321 0 DCD

GeorgiaPower A U.S. Nuclear Regulatory Commission May 4, 1988 Page Two He hope the enclosed material will be helpful in your review. You may contact this office if you have questions. I i

Sincerely, i 2 $5 R. P. Mcdonald Executive Vice President Nuclear Operations GKM/ac/lc

Enclosures:

1. Response to RFAI on IE Bulletin 85-03.
2. IE Bulletin 85-03 Program Description.

c: Georgia Power Comoany Mr. J. T. Beckham, Jr., Vice President - Plant Hatch '

Mr. L. T. Gutwa, Manager Nuclear Safety and Licensing GO-NORMS U . S . N u c 1 e aLRegulltory_Commi s s i on . Huhing t o n . D . C1 Mr. L. P. Crocker, Licensing Project Manager - Hatch U.S. Nuclear Rf9211 tory Commistion. Region _H Dr. J. N. Grace, Regional Administrator Mr. P. Holmes-Ray, Senior Resident Inspector - Hatch 1995C wn

L

. GeorgiaPower A i

ENCLOSURE 1 l

PLANT HATCH - UNITS 1, 2  !

NRC DOCKETS 50-321, 50-366  !

OPERATING LICENSES DPR-57, NPF-5 l RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION (RFAI) - IE BULLETIN 85-03 The following is a response to the NRC request for additional information  !

on IEB 85-03 (Alan R. Herdt to George F. Head) dated April 4, 1988.  !

i Question 1.  ;

Revise the summary tables of the response dated March 12, 1987, to I include values of differential pressures for opening the following MOVs, 1 or justify exclusion of these pressures. As required by Action Item "a" l of the bulletin, assume inadvertent equipment operations.  ;

(a) HPCI MOV F004 is shown normally open in Zone 0-9 of Drawing H-16332, Revision 21, and as H0V 3 on Page 68 of BHROG Report  :

NEDC-31322 dated September 1986. How would suction from the  !

CST be ensured if this H0V were to be (a) actuated i inadvertently to the closed position upon intended initiation  !

of the system or (b) left closed inadvertently? .

(b) RCIC HOV F010 is shown normally open in Zone 0-0 of Drawing '

H-16334, Revision 16, and as H0V 3 on Page 72 of the BHROG Report. The question in Item 1(a) above applies here also. .

(c) HPCI HOV F007 is shown normally open in Zone E-5 of Drawing  :

H-16332, Revision 21, and as MOV 8 on Page 68 of the BHROG i Report. How would discharge to the reactor vessel be ensured  !

if this MOV were to be (a) actuated inadvertently to the closed [

position upon intended initiation of the system or (b) left '

closed inadvertently? r (d) RCIC MOV F012 is shown normally open in Zone E-6 of Drawing ,

H-16334, Revision 16, and as HOV 8 on Page 72 of the BWROG (

Report. The question in Item 1(c) above applies here also, j l

Resoonse to Question 1:  !

i The differential pressure calculations for the four valves which consider l' valve mispositioning errors are not available to provide to the NRC at this time. The BWR Owner's Group (BWROG) report (Reference 1) concluded i that the inadvertent valve operation information was beyond the design  !

basis of the plant. As such, the BHROG methodology for calculation of '

1995C El-1 05/04/88 SL-4431 t

""6 , - - - - . . - . - - _ . _ - . _ , , _ ._ - _ - _ - . . - _ . . .

Georgia Powerkh ENCLOSURE 1 (Continued)

BESPONSE TO RFAI - IE BULLETIN 85-03 differential pressure was not developed. If required. Georgia Power Company would use this methodology to calculate the Hatch-specific differential pressure as we did for the valves in our March 12, 1987, submittal.

He understand that the question of whether or not valve mispositioning should be considered under this program is still under discussion and that a revision to IEB 85-03 may be issued shortly. Although GPC may elect to follow the BWROG "position" delineated in the Reference 2 letter, we strongly disagree with any precedent which causes us to consider events beyond the plant design basis in this IEB 85-03 program.

Question 2:

Revise the RCIC summary table of the response dated March 12, 1987, to include Trip and Throttle Valve F524 leading to the RCIC Turbine, or justify its exclusion.

This HOV is shown in Zone D -3 of Drawing H-16335, ,

l Revision 11 for Unit 1, and as HOV X on Page 74 of the BWROG Report. Is this MOV meant to be identified with a number in Zone C-9 of Drawing H-26024, Revision 13 for Unit 2? Assume inadvertent equipment operations, as described in Item 1 above.

E11ponse to Question 2:

Valve number X in Reference 1 functions as the RCIC turbine trip and throttle valve. The active safety function of the RCIC turbine trip and throttle valve is to trip closed when required to protect the turbine and ,

l pump. The closure of the valve, when tripped, is spring actuated. The motor operator on this valve is only used to reset the valve to the open position following a turbine trip.

The differential pressure across the RCIC turbine trip and throttle valve during opening is negligible. The basis for this is that, prior to resetting the RCIC turbine trip and throttle valve, the RCIC system steam admission valve located upstream of the trip and throttle valve would first be closed. This action resets the RCIC system startup logic (i.e.,

the ramp generator for the RCIC turbine). The RCIC turbine trip and throttle valve above the seat drain upstream of the valve will vent steam that is trapped between the closed steam admission valve and the trip and throttle valve to the turbine exhaust line drain pot. This will reduce the differential pressure across the turbine trip and throttle valve to a negligible value prior to valve opening.

Unit 2 drawing H-26024 does not show the master part list (HPL) number for MOV X and will be corrected.

1995C El-2 05/04/88 SL-4431 m,

Georgia Powerkh ENCLOSURE I (Continued)

RESEORSE TO RFAI ___IE_ BULLETIN 85-03 Question 3:

Revise the summary tables of the response dated March 12, 1987, to include values of differential pressure for opening and closing the following MOVs, or justify exclusion of these pressures. According to Pages 55 and 59 of the BWROG Report, these CST test return valves have no safety action; however, utilities are expected to report differential pressures for testing, per Note "o" on Page 66.

(a) HPCI MOVs F008 and F0li are shown normally closed as MOVs 5 and 6 on Page 68 of the BWROG Report.

(b) RCIC MOV F022 is shown normally closed as MOV 5 on Page 72 of the BHROG Report, gesponst_t2_0y1511on_3:

The plant design basis evaluations for transient and accident responses analyzed in the FSAR assume the HPCI and RCIC systems are in their normal standby condition at the start of the event. This assumption is made because of the low probability of the system being in a test mode or out of service during the occurrence of an abnormal event. Based on this assumption, the HPCI MOVs F008 and F0li and the RCIC MOV F022 perform no active safety function during FSAR design basis events. These valves would not be included as part of GPC's IEB 85-03 program, especially since they are not among the nine valves of question relative to the mispositioning issue. (See response to Question 1.) Nevertheless, the Unit 2 summary tables from the March 12, 1987, submittal have been revised to includt these calculations and appear at the end of this enclosure. Unit I results will be similar and will be available at a l

later date. It should be noted that operation of these valves during system flow tests demonstrates their capability to operate against differential pressures that occur during testing.

Question 4:

The proposed program for action items b, c and d of the bulletin is incomplete. Provide tha following details as a minimum:

(a) commitment to justify continued operations of a valve determined to be inoperable, 1995C El-3 05/04/88 l

SL-4431 m'

7 i 4 Georgialbwer A ENCLOSURE I (Continued)

RESPONSE TO RFAI - IE BULLETIN 85_03 (b) description of a method possibly needed to extrapolate valve stem thrust determined by testing at less than maximum differential pressure, (c) justification of a possible alternative to testing at maximum differential pressure at the plant.

(d) consideration of pipe break conditions as required by the bulletin, and (e) description of program for selection of switch settings (i.e.,

torque bypass,. position limit, overload) for valve operation.

Resoonse to Ouestion 4:

(a) Much of the static HOV testing of the HPCI and RCIC valves was performed during the Unit 2 Refueling / Maintenance outage and similar testing is planned for Unit I during the Fall 1988 cutage. During the outage, HPCI and RCIC would not be required; therefore the valve could be instrumented and tested in the as-found condition and set up within IEB 85-03 program specifications without having to enter a limiting condition - for operation (LCO) for the applicable system.

For bulletin valves tested prior to shutdown (or for selected valves which will be tested at high differential pressure), the HPCI or RCIC system was (will be) declared inoperable and the LCO entered.

The valve was (will be) adjusted. If necessary, so the as-left condition was within program specifications and the system returned to service. In the very unlikely event that the valve could not be mace operable within the allowable outage time (A0T), GPC would probably pursue alternate paths of justifying continued operation (i.e., by analysis, repair, or replacement). If these efforts were unsuccessful and the LCO expired, appropriate actions per Technical Specifications would be taken.

(b) See Enclosure 2.

(c) See Enclosure 2.

(d) Consideration of pipe break conditions was included in the differential pressure calculations reported in our NRC submittals.

They were also factored in the establishment of permissible torque and thrust settings. (See Er. closure 2.) Georgia Power has no plans 1995C El-4 05/04/88 SL-4431 rwn _

Georgialbwer b ENCLOSURE 1 (Continued)

RESf0NSE TO RFAI - IE BULLETIN 15-03 to test these valves at full differential pressure, but will perform a static MOV test and adjust the required settings per the Limitorque equations relative to the maximum differential pressure expected during accident conditions.

(e) See Enclosure 2.

l l

1995C El-5 05/04/88 SL-4431 rxm

Georgia Power d ENCLOSURE 1 (Continued)

RESEQMSE TO RFAI - ILMLLETIN 85-03

REFERENCES:

1. NEDC-31322, "8HR Owners Group Report on the Operational Design P sis of Selected Safety-Related Motor Operated Valves," September, 198(.
2. Letter, R. F. Janecek (BWROG) to J. H. Sniezek (NRC), same subject, dated March 28, 1988.

l l

l l

l l

1995C El-6 05/04/88 SL-4431

,x m

go. 4 0 0% $ $ $ 5 $ 5 g "

$ $ 0 0 0 m =

c _h " * * * *

  • I I W #"
  • Q * * *
  • W W Eg et , -

I ERO E 9 9 n

=

w a . m e e 2 a mE

  • t o a M h + + a A C 3 C 3 3  : - .

"E b d og k 5 O E $ 3 d d d N N d d d D

E E

%. o c E E g 3 5 E E E 3 8 8 E E W E W 5 g E E E

. . = = w m m = = w w - = = =

=m - - - - -

. m m - g *- - -

= = g th E E E E E D S S E h E E E e h k h

wm N N N E N z $ m M N N N i alge m sm e a m e a 3

o ag o

=

m a o, u

g e m

m e

o e

m e

m m e

. I l

s a

' g W t n ,

j a h g d E E E "

= e

. g. .

. = = = _ e*

$ t % = S  !!! W W W 5 I = E =

E

? =

b 30 g

m_. m = =

e a

r E

y -

=

m m

y a 5" 4" e+

s 4" ( E e.

E t"

a e.

a

=.

- SE m

e e

m e e k m

a ae e e, e e

8 e e e e e

]c e

g "g ti i i siie a a i ssiiiisis i

N N N g N N N N g g M c

o c -c a  :- e e g m e e s =

. g 3

s m

s

~ e e e e ed e ~ m Egz d te an W

e e W

e

=

a

=

a w

w w

a w

a a

= m a

m a

=

a E

=

m a s m =

a

=

e M

e 7 t

-, m e -

. E g > >

$ W W W d # w w g -

w w $ w g w w w w a m W w I

u E

a

$_ $_ u E E * # E d d I I d d s e _ _ E E = w * - -

d d W d g -

m w = c - - -

m , _ _ d W , ,-

v=

_3 g

- =

g w g = = - - - -

- =

E _ = d w 5 - . . g g s y g = " "

= , E = = -

w e e -

y = =

g-w E _ c 5 E E ,_ =_

, = - g g g g W e a g = = = = = m a m m m - w w g g a E E e e e - -

I e m m a =

.E W

=

W

=

=

m 2 2

- _2 m m

m m e I

c 5 h m

E .E- E W W

. - _ _ - _ _ _ =_ .

w I gg

- - w w e

s e

s e w w d W E d d E d d

=

E I e 8- g g g g g I

~ ,,5 - m a 7 g . . m m m . . - -

E' g . . m a _

- =

. . , m m m e e . ,

2 2 5 E -

w *- ~

b e g b

  • E d,h* =8  ! a =

, . = w e" e- e

=

ti a m

- w: # mE - - = . = g =

g -

g g g g a e ~ ~

E 3l *" M" W S a g e - ~

g g g 12 e - e m

. m m m

= >

m g,- g& Ew h' h" M = E a a w

w g

y = 2 e 3

a l

i

,e da E E ,

m m

_ - g = = = = -

g - m i

3" = w=

w e

m e "k

=

k

=

k .=- W .m. I a.

. e.

a I e a m

o m . =

1 "J d

! 5- " "

  • g a g - = c 0 = = 0 0 M M E =

l DMU$.

mj~ =$ 8 2 2 , e E e  ; e  ; e e e e e c  :

$n Eb

=W h b = b b b b = b = b b b b b b b l

=sEm x = n n = n x = n n n n = n w w n n

I

- g%an. 'N m m m m m m n= R:

m m m m m m w = a a m ws s a w w w w

= = = w = w w m

w sa sw ma w s4

~ m e

E 8 =

s a - - - = c 8 m 3 A & A d m m *

=

e 5 IIi5 5 E B aaiin5 a < o E

. R d

i

.o a5 as

~-

s 5 s s R

n z w

s w

s w

w =

G w m aw e -

a w

w s

w s

w a

=

s w

a w

a a E

m s

a s

a m

a a

a

=

= lmm ]

= .

E a

a a

s a

8 a

a w

=

s w

=

a W

= W W a d d W W W m = W $ = W = W m W W W W Eeu e u

e u

e=

e e e a e e e e e

=

e e e e e a o u o o u o u o o a u u u a

I a -

s = s e a @

, = = z = a i =

  • M m e m M m s - s e s

=

i s g g t - t t e - d e d f E e+ 5 5 m - m m m a e a a e e t g + c -

e e+

a c

ts -

- g w n e = m a w = m m = =

a M c m

.: . t t -

t t t -

t t t t  ? t t t V I t i e- am a = a a a = a a s a = = a a a a a l c , =a o

l 3

- G n

u a

e u

s e

u s

e u

s e e u

s aus e e u

=

e a W W e

E W W = a a u

==

-- s s u

e u u e E

=

m e

o

& e

=

W

=

a e

a m e

a 5

a

$ 5 a a r d W

=

M e W.

e i o a. =- = a o u u -

a gn5 2 w

a g 8= g y y w g w e ' g y y

  • W W w w w w *
  • w w w w w w - =

w w w w e e - -

g w Y w g g * * * * *

  • g
  • g g a 8 s - -

w d W d d w W W - -

E l _ = m a m w - - - -

w - -

w w t a u m -

a a a a > - -

= = -

d d I

  • *e
  • R = = = = 8 3 3 - . s

- -

  • su = - M W 8 W m sy y a - =

e w - - - -

e y g" 5" E e

= a a - -

s s= a u

a s l

z a a =

e e= g g

=

II8 e m m m

=

m a w

a w

a E E a l mW = =

W m u _2 _3 5

=

5 m B h h h W E E W M W

= u m m m = u - - > > m N M M M M M M M M M M M M M M M M M

=

I sg .

S w

g g .

=

bbbb g

u a

s -

2 a

S

=

W m

m m

a m

a m

a m

a m

a aww

=

  • w w

w w

~ w -

= * "

3 . . = ==5 2 5 $ 5 5 5 m gr5 eg =I

=-

=

saa: =

a aae aaaaaaa-=

u mu

= a e e e - - = -

a -

e a a m m m s s 3 .

W

= - ~

e5u

- Ms s - m W E = " " a "s u

= 2 2 w w w g g k m

, =

B %W W s

m s

m I

e 2 h

t h

m b

m k

m b

m W m g W W W 3 m . >

ew M> e. e e e x = m a e e e s = 8 8 e e

$ 2' dM M E M M W W W M n" uw

= M M M S S S 3 3 e g5C-

- 5 - = o ~ m . . ~ . . - - m . . m E8 8 3 5 3 . .

ME"= "

Et t t t t 3

t 3

t 2

t 9

t 3

t 3

t 3

t 3

t E

t t S

t 2

t t

ma m m m a m a a m a a m m m a a a m aQE NmW W W W W W W W W W W W W W W W W W

L. : . :

GeorgiaPower d ENCLOSURE 2 PLANT HATCH - UNITS 1, 2 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 LE BULLETIN 85-03 PROGRAM DESCRIPTION Introduction IE Bulletin 85-03 addresses potential problems associated with switch settings on certain safety-related motor-operated valves. The bulletin was issued in response to several events at operating nuclear plants in which safety-related valves failed to operate due to improper switch settings. The bulletin requests each plant to implement a program to set and maintain certain MOV switches to ensure valve operability under maximum differential pressure conditions.

The program developed for Plant Hatch can basically be divided into four sections which correspond to Action Items a, b, c, and d of tha Bulletin. These sections include the following:

1. Identification of Valves and Determination of Maximum Differential Pressure.
2. Establishment of Correct Switch Settings.
3. Switch Adjustment and Demonstration of Operability at Maximum Differential Pressure.
4. Development of Procedures to Ensure that Switch Settings are Maintained for the Life of the Plant.

Each section of the program, along with its current status, is outlined t,el ow.

I. Identi fi rJtion of Valves and Determination of Maximum Differential Pressure The Hatch response to Action Item "a" is based on the "BHR Owners Group Report on the Operational Design Basis of Selected Safety-Related Motor-0perated Valves." This report identified the BHR valves covered by the bulletin and outlined a methodology for calculating the maximum differential pressure for each valve. For Plant Hatch, the bulletin covers a total of 22 valves on Unit I and 23 valves on Unit 2, all contained within the HPCI and RCIC systems.

1995C E2-1 05/04/88 SL-4431c 700775

GeorgiaPower A ENCLOSURE 2 (Continued)

IE BULLETIN 85-03 PROGRAM DESCRIPTION This section of the program has been ctopleted, and an initial submittal identi fying the bulletin valves and their maximum differential pressure was transmitted to the NRC on October 2, 1986. This submittal was subsequently amended on March 12, 1987, to revise the maximum differential pressure for certain valves.

II. Establishment of Correct Switch Settinas This section of the program can be divided into three parts, including: A. Switch Functional Review, B. Calculation of Required Opening and Closing Thrust, and C. Engineering Evaluation of Operator Capability.

A. Switch Functional Review The elementary wiring diagrams for each of the valves was reviewed to determine the design function of each of the switches contained in the Limitorque operator. In addition, the applicable maintenance procedures were reviewed to determine the current method for setting each of the switches. The results of this review are summarized below.

1. Open Torque Switch - This switch is not utilized in the control circuit of any bulletin valves.
2. Close-to-Open Torque Bypass Switch - This switch is not required because the open torque switch is not utilized in the control circuits of any bulletin valves.
3. Open Limit Switch - This switch is utilized to trip the operator in the opening direction. The switch is adjusted to ensure that inadvertent backseating due to inertia does not occur.
4. Close Torque Switch - This switch is utilized to trip the operator in the closing direction. The switch setting is currently based on manufacturer recommendations.
5. Open-to-Close Torque Bypass Switch -

This switch is utilized to bypass the close torque switch during the initial 1/8 in. of travel in the closing direction.

1995C E2-2 05/04/88 SL-4431C

""5

GeorgiaPower A ENCLOSURE 2 (Continued)

IE BULLETIN 85-03 PROGRAM DESCRIPTION 6.

Close controlLimit Switch circuit of any- bulletin This switch is not utilized in the valves.

7. Motor Overloads - The motor overloads are jumpered out during normal plant operation on all bulletin valves.

The motor overloads are in service only durinp routine surveillance and post maintenance testing.

The switch functional review indicated that the design '

philosophy of the operator trip scenario was sound and that it afforded the valve the maximum opportunity to perform its intended function. The significant switches, with regard to valve operability, are the open limit switch and the close torque and torque bypass switches. The setpoints for the open limit switch and the close torque switch are delineated in the applicable maintenance procedures. The close torque i switch settings are currently based on information provided by the valve and operator manufacturers and are in terms of switch position rather than engineering units.

\

In order to evaluate the adequacy of the torque swit h '

settings and operator sizing, it was necessary to know the minimum required thrust to open and close each valve under the maximum differential pressure. Standard Limitorque equations were used to revalidate the sizing and settings for full differential pressure. Although documentation on the valve and operator manufacturers' original torque switch setpoints was available, the detailed engineering l

' calculations sometimes were more difficult to locate. In addition, the origiral thrust calculations were based on i system design pressures rather than the actual expected maximum differential pressures. It was determined that the required thrusts to open and close each valve under its maximum differential pressure should be recalculated to 3

verify operator sizing and torque switch setpoints.

B. Calculation of Required Opening and Closing Thrust In order to calculate the required opening and closing thrusts, it was necessary to obtain data on the physical characteristics of the valves. This information was not always available on drawings or in vendor manuals and required going back to the original equipment manufacturer.

Each valve vendor was contacted and requested to provide the following information:

1995C E2-3 05/04/88

SL-4431c 4

700776

7

  • Georgia Power d ENCLOSURE 2 (Continued)

IE BULLETIN 85-03 PROGRAM DESCRIPTION

- Seat ring diameter.

- Disk or plug coefficient of friction.

- Stem efficiency. ,

j

- Stem diameter, pitch, and lead.

Maximum allowable torque.

These data were used to calculate the required opening and closing thrusts for each valve. These calculations were performed utilizing the standard Limitorque empirical equations for gate and globe valves. These calculations provide the minimum required thrusts to open and close each valve. The next step was to perform an engineering evaluation to determine whether each operator was capable of {

providing the required thrust.

C. Engineering Evaluation of Operator Capability A complete review of the Limitorque operator for each valve was performed to determine the maximum torque rating of each operator.

This included a review of operator capability at derated voltage (90-percent voltage for AC and 84-percent voltage for DC). This review verified that the original operator setting was sufficient to operate the valves against the maximum differential pressure and also established an upper limit above which the valve or operator could sustain mechanical damage.

With this section of the program complete, information became available regarding the minimum torque required to open and close each valve and the maximum allowable torque to avoid damage to the valve or operator. This information (in the form of "target" ranges of permissible torque and thrust) has been utilized to evaluate switch settings in the field and to adjust switches, as required to ensure operation at maximum differential pressure without damage to the valve or operator. Table 1 contains a summary of the MOV calculations for Unit 2. Calculations for Unit 1 will be available at a later date.

III. Switch Adiustment and Demonstrate Ooerability at Maximum Differential Pressure This section of the program can be divided into three parts, including: A. MOV Diagnostic Testing, B. Signature Analysis, and C. Differential Pressure Testing.

E2-4 05/04/88 l - 31c l

l wn

. GeorgiaPower A ENCLOSURE 2 (Continued)

IE BULLE'IN 85-03 PROGRAM DESCRIPTION A. MOV Diagnostic Testing on Unit 2 In order to veri fy the operability of each valve, the Limitorque Motor A:tuator Characterizer (MAC) was utilized.

This system allows the following parameters to be monitored and recorded during the respective closing or opening stroke of the valve:

- Stem thrust.

Output torque.

- Motor current.

- Spring pack displacement. '

Open torque switch.

- Open torque switch bypass.

- Open limit switch.

- Close torque switch.

Close torque switch bypass.

- Close limit switch.

Valve signatures were taken in the ts-found condition in ,

accordance with procedures. These data were evaluated in conjunction with the calculated data in Section II. If an adjustment was required, a new set of signatures was taken to verify that the setting.; were correct and to provide a record of the as-left condition.

B. Signature Analysis The static signatures taken with the MAC equipment were

analyzed to evaluate each valve's operability at maximum

! differential pressure. The static signatures quantified all valve loads other than those due to differential pressure in terms of thrust and/or torque. In addition, the status of the torque and limit switches was monitored with respect to time and was directly related to thrust and torque at the i

switch trip points. By comparing the thrust at the torque

, witch trip point to the calculated required thrusts to open and close the valve, a determination of valve operability at maximum differential pressure was made. If the thrust at the torque switch trip point was determined to be greater l than the required opening and closing thrust, the valve will l be capable of operating against the maximum differential pressure.

l 1995C E2-5 05/04/88 i

SL-4431c

!=m. - - . . - ... . - _ -- - -

Georgia Power A -

ENCLOSURE 2 (Continued)

IE BULLETIN 85-03 PROGRAM DESCRIPTION C. Differential Pressure Testing A differential pressure test will be conducted on the steam admission valves (2E41-F001 and 2E51-F045) of the Unit 2 HPCI and RCIC systems. Unit 1 testing will be completed at a later date. The purpose of these tests will be to help validate the methodology outlined in Section III.B for determining valve operability at maximum differential pressure. The steam admission valves were chosen due to their accessibility, high differential pressure, and the fact that these valves are stroked during system operability tests.

Each of the above valves will be outfitted with the MAC diagnostic equipment and stroked during a system operability test. The data obtained during this test will be evaluated in conjunction with the calculated thrust values to ensure that the Limitorque equations are providing sufficiently conservative results.

IV. Develooment of Procedures to Ensure that Switch Settinas are Maintained for the Life of the Plant ,

Existing plant procedures are presently being reviewed to identify changes necessary to ensure that switch settings are maintained for the life of the plant. A policy regarding periodic and/or maintenance-related retesting will have to be formulated prior to identifying all procedural requirements.

This policy and the procedural changes necessary to implement it i will be initiated prior to making our final submittal.

i l

l i

l l

i 1995C E2-6 05/04/88 SL-4431c wn . _ _ - . - . __ . - - _ _ . . . _. ..

1 Enclosure 2 (continued)

TABLE 1 l

l LMIT 2 IfN SIAliARY OF COO.USIONS l l

RATED RE @ REW WTR TARGET tut 0)E TAICET T2tlST LIWITl2 PAAAETER VALVE ETOR WTOR TORQUE RANGE RAEE FCR )

DESCRIPTION TORO uneneneenonennennunnensee no LE TCRCLE VAL.V.EIPL

e. nemennenuneeKRATED WINIH WAXIM WINIM WAXil&Al LPPER TARGE unnuennenennunenneennununeeeneen (FTLB)(FTLB) (LB) nunnenunneennenununununn enouenenben(FTLB) seene(FTLB) (FTLB) (LB) ennenenenenunnunnuenenenununennu '

Z414001 TWBINE STEAW SLPPLY 80 48.18 57.36 471.75 652.00 23843 32992 OPER W AVAll TOROVE Z414002 STEAW SUPPLY 120 W ISOLATION 25 20.52 25.33 472.12 639.20 23880 32305 OPER MAX AVAll TORM 2E414003 STEAW SLPPLY OllTBOARD ISCLAtl0H 40 21.80 25.96 472.12 850.00 23860 42958 OPER WM ALLOW TOR 1!

2E414304 PLAP SUCTION CST 15 4.12 4.91 91.46 361.84 4137 16727 OPER WM AVAll TORM 2E414006 PtAP 120ARD DISCmRGE 150 35.36 42.10 498.76 2200.00 19703 88908 VALV Wu A'.' 5 TCRM 2E414012 WIN FLOW BYPASS 25 7.39 8.79 123.M 342. M 8824 24000 OPER Wu A',LC# TWST Z414041 PtnP SUCTION Ff0d SLPPRESION POOL 15 8.27 9.85 173.18 348.78 7832 15775 OPER Wu AVAll TORM E41-F042 PLAP SUCTION FRCnl StPPRESION POOL 15 8.27 9.85 173.18 348.78 7832 15775 OPER Wu AVAll TOR 72 2E414059 COOLING IIATER SLPPLY 10 0.62 0.74 10.48 135.E2 1060 14000 OPIR Wu Al. LOW ThRUSi l.

2E414104 VAQAll BREAKER ISOLATION 2 0.35 0.43 8. 5*. 54.93 1015 6537 CPER Wu AVAll TORM 2E414111 VA3AAi BREAKER ISOLATION 2 0.35 0.43 8.53 54.93 1015 6537 OPER WM AVAll TORM 2514007 STEAW INBOAA0 ISOLATION 10 6.71 8.29 83.82 105.32 5618 9300 OPER MAX AVAll TOR M i

2514008 STEAM OUT20JA0 ISOLATICN 10 6.27 7.46 63.82 112.80 5618 9961 CPER W.a AVAll TORM 2E51-F010 PLAP SUCTION CST 5 1.53 1.82 26.32 fr.00 1751 5989 CPER W ALLCW TORM 2E514013 PLnP ISOLATION lh3 CARO 15 7.75 9.22 78.88 189.20 5752 12373 OPER WA AVAll TOR M 2E514019 TEST BYPASS TO CST 25 5.44 6.48 37.23 135.82 3843 14CCO OPER WM All0W THR.'ST E514029 PtnP SUCTION StPPRES$10N POOL 5 2.21 2.63 34.74 87.50 2312 5822 OPER KAX AVAll TOR 1I 2E514C01 PthP SUCTION STPRESSION POOL 5 2.21 2.83 34.74 87.50 2312 5822 OPER WAX AVA!L TORM 2E5i4045 TWBINE STEAW SLPPLY 40 15.30 18.21 192.52 295.26 15649 24000 OPER WAX ALLOW T R ST I

2E514046 (COLIN 0 RATER SLPPLY 10 1.40 1.67 23.58 135.62 2434 14000 CPER W ALLCW TR4T l

2E514104 YAD.AAI BREAXER ISOLAtlCN 2 0.36 0.44 7.31 45.00 1009 0293 CPER MAX AVAll TCRM 2E514105 YAD.I.Al BREAKER ISOLATich 2 0.36 0.44 7.31 45.00 1009 8293 CPER lLAX AVAll TORM 2E514119 STEAM ADilS$10H BYPASS 5 1.50 1.78 13.19 44.99 1625 0037 OPER WAX AVAIL TORM l.

l E2-7 5/4/88 l

l l

i I