ML20059L997

Summary of 931015 Meeting W/Util in Rockville,Md Re Licensee Program on MOVs & Completion of Actions Recommended in GL 89-10.List of Meeting Attendees & Handouts Encl

ML20059L997
Person / Time
Site:	Wolf Creek
Issue date:	11/12/1993
From:	William Reckley Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
GL-89-10, NUDOCS 9311180065
Download: ML20059L997 (27)

Text

.*

• f November 12, 1993 ,

i i Docket No. 50-482 LICENSEE: Wolf Creek Nuclear Operating Corporation i FACILITY: Wolf Creek Generating Station

SUMMARY

OF MEETING HELD ON OCTOBER 15, 1993 TO DISCUSS MOTOR OPERATED VALVES AND COMPLETION OF ACTIONS RELATED TO GENERIC LETTER 89-10 AT WOLF CREEK GENERATING STATION i On October 15, 1993, members of the NRC staff met with representatives of Wolf  !

Creek Nuclear Operating Corporation to discuss the licensee's program related to motor operated valves (MOVs) and completion of actions recommended in Generic Letter 89-10, " Safety-Related Motor-0perated Valve Testing and Surveillance." A list of the attendees is provided as Enclosure 1. The

[

handout associated with the licensee's presentation is provided as  ;

Enclosure 2.

The licensee presented their approach to reducing the number of MOVs which i

! would be subject to differential pressure testing. Discussions included the i need for programs to ensure continued valve operability, recent issues such as thermal binding, and future inspection plans. The staff considered it  :

appropriate for the licensee to submit an update of their MOV program in  !

accordance with the reporting requirements of the generic letter. l l

Original Signed By William D. Reckley, Project Manager Project Directorate IV-2 Division of Reactor Projects III/IV/V j

Office of Nuclear Reactor Regulation '

Enclosures:

DISTRIBUTION

1. Attendance List Docket File. EAdensam

2. Handout NRC PDR OGC Local PDR EJordan PDIV-2 R/F ACRS (10)

TMurley WJohnson, RGN-IV FMiraglia NRC Participants JCallan EPeyton JRoe OFFICE PDIV-2/LA PDIV-1/PJ PDIV-2/.D NAME EP t WRec eyh SBlaIh DATE 11/9/93 11/1 0/93 11/;D/93 / / / /

co" hES'/NO hNO YES/[0) u YES/NO YES/NO 0FFICIAL RECORD COPY an n m, NRC RE CBTfB C8PYi '

9311100065 931112 PDR ADOCK 05000482 '

P PDR

i . < - l

\

November 12,1993 l

cc w/ enclosures Jay Silberg, Esq. Mr. Otto Maynard Shaw, Pittman, Potts & Trowbridge Vice President, Plant Operations '

2300 N Street, NW Wolf Creek Nuclear Operating Corporation i Washington, D.C. 20037 P. O. Box 411 ,

Burlington, Kansas 66839 '

Mr. C. John Renken i Policy and Federal Department Regional Administrator, Region IV Missouri Public Service Comission U.S. Nuclear Regulatory Comission P. O. Box 360 611 Ryan Plaza Drive, Suite 1000

• Jefferson City, Missouri 65102 Arlington, Texas 76011 Regional Administrator, Region III Mr. Kevin J. Moles U.S. Nuclear Regulatory Comission Manager Regulatory Services 799 Roosevelt Road Wolf Creek Nuclear Operating Corporation Glen Ellyn, Illinois 60137 l P. O. Box 411

Burlington, Kansas 66839 Senior Resident Inspector U.S. Nuclear Regulatory Comission Mr. Neil S. Carns j P. O. Box 311 President and Chief Executive Officer Burlington, Kansas 66839 Wolf Creek Nuclear Operating Corporation Post Office Box 411 i Chief Engineer Burlington, Kansas 66839 Utilities Division ,

Kansas Corporation Comission  !

1500 SW Arrowhead Road Topeka, Kansas 66604-4027 Office of the Governor State of Kansas l Topeka, Kansas 66612  !

l Attorney General '

Ist Floor - The Statehouse Topeka, Kansas 66612 County Clerk Coffey County Courthouse Burlington, Kansas 66839 Mr. Gerald Allen Public Health Physicist Bureau of Environmental Health Services Division of Health Kansas Department of Health and Environment 109 SW Ninth l Topeka, Kansas 66612 i

l

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ENCLOSURE 1-LIST OF ATTENDEES ,

MEETING WITH WOLF CREEK NUCLEAR OPERATING CORPORATION l l REGARDING MOTOR OPERATED VALVES AND GENERIC LETTER 89-10 1

OCTOBER 15, 1993 .

i l

( NAME ORGANIZATION

, Candace Sprout WCNOC l

Lanny Ratzlaff WCNOC Steve Wideman WCNOC  ;

Tom Bergman NRC/NRR/PDIV-2 Tom Scarborough NRC/NRR/EMEB  :

Mike Runyan NRC/ Region IV l Tom Westerman NRC/ Region IV '

l Marc Huber NRC/ Region III i

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e i

l l

l l

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l

WCNOC METHODOLOGY FOR ~

COMPLIANCE AND CLOSURE OF NRC GENERIC LETTER 89-10 E

PRESENTATION TO NRR AND REGION IV A WASHINGTON, D.C. E

~

OCTOBER 15,1993

~

WOLF CREEK NUCLEAR OPERATING CORPORATION'S MOTOR OPERATED VALVE PROGRAM

1. MOV PROGRAM DESCRIPTION: WCNOC-85 ll. ORIGINAL METHODOLOGY THROUGH REFUEL VI 111. FEEDBACK, EXPERIENCE AND LESSONS LEARNED IV. HIGH MARGIN METHODOLOGY V.

SUMMARY

Page 2 of 24

l

) .' l. WCNOC MOV Proaram

Description:

WCNOC-85 l 4

PURPOSE: '

l 1. Ensure the operability of safety-related MOV's ,

! 2. Systematically approach, resolve, and address  !

l industry concerns and issues l 3. Maintain a high level of reliability for the MOV's l i

i j CONTENTS AND PROCESS: l l SECTION I: Program Description l

4 SECTION 11: Design Basis Analysis  :

l SECTION lil: Maximum Expected Differential Pressure i

i j SECTION IV: Reduced Voltage Evaluation i

SECTION V: Seismic & Stress Analysis

SECTION VI

Thrust & Torque Requirements t

SECTION Vil: Differential Pressure Testing l

SECTION Vlll: Tracking & Trending of MOV Performance l APPENDICES A: Scope of Valves for NRC GL 89-10 i

B: Justifications and Evaluations j C: MOV Team Organizational Chart

. D: Design Bases Verification i

j Page 3 of 24

II. ORIGINAL METHODOLOGY THROUGH REFUEL VI MOV PRIORITY: The original MOV priority at WCNOC was based upon safety significance, high differential pressure (open and close) and valves known to have low margin from Refuel V.

The top 52 GATE and GLOBE valves (Westinghouse, Anchor Darling, Masoneilan, Velan, Gimple) were then targeted to be the first through our enhanced MOV program and scheduled for dynamic testing during Refuel VI.

WCNOC-85 PROCESS:

1. DESIGN CONFIRMATION: Determine the design basis thrust / torque values for the application and optimize the actuator appropriately to maximize margins.

2. AS-FOUND STATIC VOTES TEST: Static test prior to any field work.

3. PRE-LOCAL LEAK RATE TEST (LLRT), if required.

4. REPLACE / REFURBISH (OVERHAUL) AND OPTIMlZE THE ACTUATOR i

t 4 .

Page 4 of 25

_ ~ _._.____ __ _ _ . - _ _ . _ _ _ _ _ _ . _ _ _ _ _ _ _

5. SET-UP VOTES TEST: Static test with torque monitored to optimize the thrust within the allowable window between the minimum required thrust (MRST) and maximum allowable thrust (MAST) values.

6. DP TEST: Dynamic test with reduced voltage and torque monitored.

7. BASELINE STATIC VOTES TEST: Static test with torque monitored (following the DP test) for comparative information against DP data and future static test data.

4

8. AS-LEFT STATIC VOTES TEST: Static test without torque to ensure the

MOV remains at the prescribed thrust value after the intrusive test equipment is removed.

9. POST-LOCAL LEAK RATE TEST (LLRT), if required.

4 i

Page 5 of 24

10. CLOSURE FROM G.L. 89-10: (Permanent thrust values determined including margin for degradation)

DP tests at > 100 % Design Basis: The ultimate design basis thrusts can be determined based upon DP testing results.

(NO FURTHER ACTIVITIES REQUIRED FOR CLOSURE)

DP tests at < 100 % Design Basis: Extrapolation and/or other data (EPRI, industry, vendor, etc.)

utilized to justify the ultimate design basis values.

(ADDITIONAL ACTIVITIES REQUIRED PRIOR TO CLOSURE)

11. PERIODIC TESTING: Periodically verifies thrust values are within the confirmed / permanent window for operability.

Page 6 of 24 i

Ill. FEEDBACK, EXPERIENCE AND LESSONS LEARNED i Differential pressure testing in accordance with NRC G.L. 89-10, where l practicable, has been initiated mainly due to the concern of motor operator capabilities and margin to ensure that the valve will perform its intended design function over a given period of time.

A. KEY REASONS FOR DP TESTING:

1. The valve seat coefficient of friction (valve factor) is a valve-specific factor that can be difficult to bound or approximate and significantly affects the DP load (thrust).

2. The stem / thread coefficient of friction is unknown unless torque and thrust measurements are obtained. If this factor is unknown, actuator / motor thrust capability is indeterminate.

3. Load sensitive behavior (commonly referred to as the rate of loading) cannot be determined analytically or if it even exists for an MOV. Without DP testing, a bounding assumption may be difficult to determine or may be

. an unnecessary penalty. This phenomonon is manifested in the stem thread coefficient of friction changing under DP loading conditions.

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Page 7 of 24

4. Reduced voltage motor capabilities, stroke time changes, and inertial effects are some of the other unknown issues that also require DP testing for validation and verification of assumptions.

B. REFUEL VI RESULTS FROM FULL DP TESTING:

Disc / seat coefficient of friction: Close Range: 0.04 to 1.02 (Average: 0.46)

Open Range: 0.02 to 1.17 (Average: 0.36)

Stem / thread coefficient of friction: Range: 0.05 to 0.22 (at Control Switch Trip) (Average: 0.14)

Rate of Loading for torque closed: Range: -8 to 19 %

(Average: + 5 %)

Percent Enertia above CST Thrust: Range: 3 to 67 %

(during DP test) (Average: 24 %)

Stroke time difference: Range: -1.82 to 0.892 sec (DP - Baseline static) (Average: 0.105 sec)

Page 8 of 24

Low DP tests These low differential pressure dynamic tests did not

( = < 200 psid) provide significant and/or any distinguishable differences in diagnostic traces than that seen on the corresponding baseline static trace

(# PRACTICABLE = REASONABLY ACHEIVABLE = MEANINGFUL) 1 4

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IV. HIGH MARGIN METHODOLOGY FOR WCNOC Based upon:

i 1

1. Remaining MOVs: Largely gate and butterfly valves with less safety significance.

2. Differential Pressures: Generally lower than those under the previous methodology.

l Previous MOVs (52): Tested Range: 66 to 2704 psid (Average: 958 psid)

( = 75% > 200 psid)

Remaining MOVs ( = 78): Design Basis Range: 33 to 2800 psid (Average: 361 psid)

( = 80% < 200 psid) i I 3. Utilization of existing data:

a. WCNOC Refuel VI results j b. EPRI Performance Prediction Program  ;

j c. Other industry data l

l Page 10 of 24

1

( 4. Specifying extremely conservative disc / seat coefficients of friction

5. Optimizing the actuator i A High Marain Window Can Be Established:

i

1. Definite conservative minimum thrust / torque requirements can be determined for each MOV/ family.

2. Relatively large thrust / torque windows can be established.

For torque closed MOVs: Thrust settings will be in the upper portion of the window and thereby inherently providing i a large degradation margin to easily

accomodate factors such as spring pack relaxation and stem lube degradation.

For limit closed MOVs: The margin between minimum required thrust i

and the limiting (motor / valve / actuator) capability will provide a large degradation margin for

factors such as stem lube or bearing coefficient

degradation.

Page 11 or 24

I I Resultina in:

1. No DP test required

2. Refurbishment / replacement schedule based upon margin available

3. Large margins created to excessively compensate for a combination of factors / degradations

4. Compliance with GL 89-10 and the preliminary draft of Supplement 6

• Testing where practicable / meaningful

• Sound basis for operability

• Grouping MOVs that are not practicable to test in a manner that provides adequate confidence in the capability to perform the design basis function

• Static testing each MOV and adjusting within conservative windows

• Utilizing both industry and plant-specific data l

• Justifying alternate approaches to dynamic testing where the licensee 4

has sufficient information te demonstrate the validityof its approach.

Page 12 of 24

EXAMPLES OF THE NEW MARGIN APPROACH Applicable to all valve models: GATES, GLOBES, and BUTTERFLYS A. GATE Valve Example (Torque Closed):

BBHV8037A/B: Pressurizer relief tank drain isolation to containment normal surnp 4" - 150# Westinghouse SMB-00 with a 15 ft-Ib,3600 RPM motor l

DP = 105 psid (OPEN/ CLOSED)

Assume: )

i Disc / seat cof = 1.0 Stem / disc cof = 0.2 Actuator rated thrust = 19,600 lbs (Using the extended thrust rating) i CLOSE OPEN Motor capability: 13,547 lbs 10,159 lbs Valve capability: 17,872 lbs 17,872 lbs Required Thrust: 3,298 lbs 4,007 lbs Page 13 of 25

GATE: Torque Closed BBHV8037A/B 14000 --- ~

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ - ~ ~ ~ ~ ' ~ ~ - '

f 3547 IMotor1] ~

% MARGIN is that 12000 -- -

amount above the Minimum Required Thrust 10159 (Motor]

10000 - - - -

311 % MARGIN

8000 --

e

~

s 154% MARGIN m

o cc z

H 6000 -

4007 3298 4bif.,1Uh,fIDjYkI$

, 0 Thrust Allowable / Capability

$:y;CN!'D[f;:sh.(${ .

, ,L y ,

._. , .,

r "'. < - g, , w Minimum Required Thrust

.3c. :n :N .- -

? ", .

2000 - ' kN 9- "

idh #a j,. . .

kk'C e' y{ mf '

P ic : .g-r r;ry ,, , . _ ,%

tg i Y: 't. t e1il.

%. ,, . O _ __g CLOSE . OPEN Page 14 of 24

. _ . _ _ _ _ _ . _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ _ _ _ _ ______________m _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _-

{

B. GATE Valve Example (Limit Closed):

BGLCV0112B/C: Volume control tank low level i isolation l

4" - 150# Westinghouse  !

SMB-00 with a 15 ft-Ib,3600 RPM motor l DP = 89 psid (OPEN/ CLOSED) .

Assume:

I Disc / seat cof = 1.0 Stem / disc cof = 0.2 Actuator rated thrust = 19,600 lbs (Using the extended  !

thrust rating)

_CLOSE OFLN ,

1 Motor capability: 17,275 lbs 12,956 lbs Valve capability: 16,000 lbs 16,000 lbs Required Thrust: 3,081 lbs 3,695 lbs Page 15 of 24

_ GATE: Limit Closed BGLCV0112B/C 16000 (Valvel 16000 - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

% MARGIN is that amount above the 14000 - - - - -- - ~

Minimum Required Thrust 12956 (Motor) 12000 --- -

10000 ~

419% MARGIN j 251% MARGIN

=

5 8000 --

E h

6000 4000 - 3695 O Thrust Allowable / Capability 3081 tiv N;j){MIti?4MIDAi { r.

.: Minimum Required Thrust

' 9M.9j , J iN N,'

... 2 t , .. ; f.;-Q-e, .* 7' 4

b. s L} .$ ff; f. - - - -

2000 -- jp, e- TiO fjs

_ , q. - , b N( * '. (

, N/u f, s 0 -- I Y CLOSE OPEN Page 16 of 24

4 l

C. GLOBE Valve Example: (All at WCGS are toraue closed)

BGHV8104: Immediate borate valve from the CCP suction isolation 2" - 1500# Velan SMB-00 with a 10 ft-lb,1700 RPM motor j DP = 139 psid (OPEN/ CLOSED)

Assume:

Disc / seat cof = 1.0 Stem / disc cof = 0.2 Actuator rated thrust = 19,600 lbs (Using the extended thrust rating) l l

! CLOSE OPEN Motor capability: 23,394 lbs 18,715 lbs Valve capability: 24,900 lbs 24,900 lbs Required Thrust: 4,401 lbs 1,809 lbs Page 17 of 24

GLOBE BGHV8104 20000 -

19600-I Actuatori - ----- - - - -

18715 (Motor) 18000 --- - - - -

% MARGIN is that 16000 amount above the Minimum Required Thrust 14000

~

- 345% MARGIN E

935% MARGIN

$ 10000 m

a:

I F-8000 6000 - ___ .-.

4401 0 Thrust Allowable / Capability 4000 "[ [;;[ ' j i ",5,f, y O Minimum Required Thrust

'f hlkk[$.$;jkhbkh;hb v 2000 '[ Yhi!h- $

.P 7 % +;; .b t ; ,

>r+ , ,;. pg. :( (!g i M* ___3'_MI W.-d 4 :

0 i I CLOSE OPEN Page 18 of 24

D. BUTTERFLY Valve Example:

ECHV0011/12: Fuel pool heat exchanger to CCW isolation 12" - 150# Fisher SMB-000 - H2BC with a 5 ft-Ib,1700 RPM motor DP = 100 psid (OPEN/ CLOSED) l l

l Assume: Bearing cof = 0.25 l Actuator rated torque = 1,300 ft-Ibs l

CLOSE OPEN Motor capability: 2880 ft-Ibs 2189lbs .

l Valve capability: 1100 ft-Ibs- 1100 ft-lbs Required Torque: 354 ft Ibs 354 ft Ibs-l l

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B_UTTERFLY ECHV0011/12 1200 --- ---- - - - - -- -

1100 [Valvel 1100 IValvel

% MARGIN is that 1000 - amount above the Minimum Required Torque 800 --

g S

ti3 coo cc x

P-400 354 354 5;

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- . , - t-n a, , . . - - 3 e i, ,.e .,5.,, Minimum Required Torque 200 g( k X > .( l'I' h lhi I*'d fi< .i H. -

E v[j';jih,; "

-(il e .

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p;t: c ,;

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• j c i CLOSE OPEN Page 20 of 24

i V.

SUMMARY

METHODOLOGY COMPARISONS ORIGINAL STEPS HIGH MARGIN STEPS DESIGN DESIGN '

PRE-LLRT (if required) PRE-LLRT AS-FOUND AS-FOUND REPLACE / REFURBISH /OPTIMlZE (See NOTE below)

SET-UP STATIC TEST SET-UP STATIC TEST (= BASELINE)

DP TEST BASELINE STATIC TEST AS-LEFT STATIC TEST AS-LEFT STATIC TEST POST-LLRT (if required) POST-LLRT NOTE: The main purpose for refurbishment is to ensure that the actuator is in the best possible condition for a " pure" DP and baseline test.

All high design basis DP MOVs will be replaced / refurbished and optimized prior to the set-up test. All low design basis DP MOVs i will be optimized prior to the set-up test. Refurbishment for these

! MOVs is also considered mandatory, but within a time frame

dependant upon the amount of margin available.

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Page 21 of 24

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MOV FLOW DIAGRAM I MOV D PROCESS I BEGINS

(

(6.1)  ; ,

f I DES'GN ARE A I DESIGN BASS DETERMINE ANALYSIS MINMWlUM VOLTAGE DAGNOSTIC REVIEW COND(TION ASSOUND _

(6 21 (6 4)

STATIC TEST (S D y

' SEISMIC & STRESS DETERMINE agggyg,g I MAKIMUM EXPECTED ,

(, .,

REV M ACCEPTADLE k

@ DFFERENTIAL PRESSURE (6 3)

(6 5) i I

h I DETERMINE I' THRUST / TORQUE e ROOT CAUSE REQUIREMENTS AND

_ _ c ANALYSS & MARGw CORRECTWE ACTION (6 6) l (616) __

I i i I i t

O M l

Y _

DAGNOSTIC SET.UP REFURB'SH AND  :

I STAE TEST A$rBUILT INFO

/ (6 9) j {

DP TEST REQUIRED D" # (6 6) y h 3

i DAGNOSTIC ,

[ DYNAMIC TEST IO N

%, ACCEPTABLE )

i DAGNOSTIC SET.UPt g

T V -j I

BASEUNE STATIC TEST (6 el (611) C M~

DAGNOSTIC AS-LEFT STATIC TEST I (6 121 l i DAGNOSBC y j PERIOOiC _i DAGNOSTIC j TEST 'j TEST i

(6 14) l EVALUATION r 1

f I

ew

( ACCEPTABtE N -

ew f

TRACKING

=

TRENDING (6 15)

PREVENT!VE I

& CORRECTWE FEEDBACK MAIN 4 NANCE l TO (6 13) l MOV PROGR AM l

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l NEW ENHANCED METHODOLOGY approach utilizing conservative factors is used to first evaluate the MOV family NO SPECIFIC (MINIMUM) MARGIN REQUIREMENTS: Each MOV family will be evaluated on a case-by-case basis.

HIGH MARGIN approach will be based on ENGINEERING JUDGEMENT from 1

evaluating appropriate and applicable data to establish justification for this method.

MOVs not providing HIGH " CONFIDENCE" MARGIN will be DP tested, if

! practicable and/or meaningful, following the ORIGINAL methodology and process.

THE MARGIN APPROACH WILL PROVIDE THE SAME CONFIDENCE LEVEL IN THE ABILITY OF THE MOV TO PERFORM ITS DESIGN BASIS FUNCTION.

ORIGINAL PURPOSE MAINTAINED: The WCNOC MOV program will continue to:

1. Ensure the operability of safety-related MOV's i

2. Systematically approach, resolve, and address industry concerns and issues

3. Maintain a high level of reliability for the MOV's Page 23 oI24

4 KEYS TO SUCCESS: 1. MOV team approach *

2. Aggressive and creative in approaching MOVs and their related activities and issues

3. Plant team work

4. Detailed planning and scheduling

5. Management / plant support l

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