ML20036A135

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Discusses Summary of 930414 Enforcement Conference Re Failure to Maintain Required Availability of Two Independent Nuclear Svc Water Sys Loops
ML20036A135
Person / Time
Site: Catawba  
Issue date: 04/22/1993
From: Merschoff E
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To: Tuckman M
DUKE POWER CO.
References
EA-93-054, EA-93-54, NUDOCS 9305100088
Download: ML20036A135 (26)
v • d • e


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APR 2 21993 Docket Nos. 50-413, 50-414 License Nos. NPF-35, NPF-52

-i EA 93-054 Duke Power Company

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ATTN: Mr. M. S. Tuckman Vice President Catawba Site 4800 Concord Road York, SC 29745-9635 Gentlemen:

SUBJECT:

ENFORCEMENT CONFERENCE

SUMMARY

(NRC. INSPECTION REPORT NOS. 50-413/93-07 AND 50-414/93-07)

.j This letter refers to the Enforcement Conference held at our request on April 14, 1993. This meeting concerned activities authorized for your Catawba facility. _ The specific issue discussed at this conference related to the failure to maintain the required availability of two independent Nuclear j

Service Water System loops. This Enforcement Conference was open for public observation in accordance with the Commission's trial program for conducting open enforcement conferences as discussed in the Federal Register, 57 FR 30762, July 10, 1992. Your presentation was beneficial in clarifying the

.l issues associated with the previous degraded Nuclear Service Water System and i

provided us with an understanding of your corrective actions. A list of i

Attendees, Enforcement Conference Summary and a copy of your handout are enclosed. We are continuing our review of this issue to determine the j

appropriate enforcement action.

l In accordance with Section 2.790 of the NRC'S " Rule of Practice," Part 2, Title 10, Code of Federal Regulations, a copy of the letter and its enclosures i

will be placed in the NRC Public Document Room.

l Should you have any questions concerning this matter, please contact us.

I Sincerely,.

hr 72 b N!#C t 47 Ellis W. Merschoff, Director Division of Reactor Projects

Enclosures:

1 1.

List of Attendees 2.

Enforcement Conference Summary 3.

Enforcement Conference Handout 9305100088 930422' PDR ADOCK 05000413 G

PDR i

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APR 2 21993 Duke Power Company 2

cc w/encls:

R. C. Futrell Compliance

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4800 Concord Road York, SC 29745-9635 A. V. Carr, Esq.

Duke Power Company 422 South Church Street Charlotte, NC 28242-0001 J. Michael McGarry, III, Esq.

Winston and Strawn 1400 L Street, NW Washington, D. C.

20005 i

North Carolina MPA-1 Suite 600 P. O. Box 29513 Raleigh, NC 27626-0513 Heyward G. Shealy, Chief Bureau of Radiological Health S. C. Department of Health and Environmental Control 2600 Bull Street Columbia, SC 29201 Richard P. Wilsca, Esq.

Assistant Attarney General i

S. C. Attorney General's Office P. O. Box 11549 Columbia, SC 29211 Michael Hirsch Federal Emergency Management Agency 500 C Street, Sw, Room 840 Washington, D. C.

20472 North Carolina Electric Membership Corporation P. O. Box 27306 Raleigh, NC 27611 Karen E. Long Assistant Attorney General N. C. Department of Justice P. O. Box 629 Raleigh, NC 27602 cc w/encls:

Continued see page 3 j

APR 2 21993 Duke Power Company 3

i cc w/encls: Continued I

Saluda River Electric Cooperative, Inc.

l P. O. Box 929 Laurens, SC 29360 T. Richard Puryear Nuclear Technical Services Manager Carolinas District Westinghouse Electric Corporation P. O. Box 32817 Charlotte, NC 28232 County Manager of York County York County Courthouse York, SC 29745 Piedmont Municipal Power Agency 121 Village Drive Greer, SC 29651 G. A. Copp Licensing - EC050 Duke Power Company P. O. Box 1006 Charlotte, NC 28201-1006 bcc w/ encl:

R. E. Martin, NRR W. Miller, RII A. R. Herdt, RII S. J. Vias, RII M. S. Lesser, RII Document Control Desk NRC Resident Inspector U.S. Nuclear Regulatory Commission Route 2, Box 179-N York, SC 29745 f

i Jen ns C

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4/g/93 4/d/93 4/

93 4/g/93 4/g/93 i

ENCLOSURE 1 LIST OF ATTENDEES U. S. NUCLEAR REGULATORY COMMISSION L. A. Reyes, Deputy Regional Administrator, Region II (RII) i E. W. Merschoff, Director, Division of Reactor Projects (DRP), RII T. A. Peebles, Chief, Operations Branch, Division of Reactor Safety (DRS), RII F. Jape, Chief, Test Programs Section, DRS, RII A. R. Herdt, Chief, Reactor Projects Branch 3, DRP, RII M. W. Branch, Acting Chief, Test Programs Section, DRS, RII G. R. Jenkins, Director, Enforcement and Investigation Coordination Staff (EICCS), RII B. Uryc, Senior Enforcement Specialist, EICCS, RII R. E. Martin, Senior Project Manager, Project Directorate 11-3, Nuclear Reactor Regulation (NRR)

T. G. Scarbrough, Senior Mechanical Engineer, Mechanical Engineering Branch, NRR W. T. Orders, Senior Resident Inspector, Catawba, DRP, RII P. C. Hopkins, Resident Inspector, Catawba, DRP, RII W. H. Miller, Jr., Project Engineer, DRP, RII M. L. Marshall, Project Engineer / Intern, DRP, RII D. M. Tamai, Project Engineer / Intern, DRP, RII DUKE POWER COMPANY M. S. Tuckman, Vice President, Catawba Nuclear Site (CNS)

J. S. Forbes, Engineering Manager, CNS R. C. Futrell, Compliance Manager, CNS P. A. McIntyre, Engineering Supervisor, CNS S. W. Brown, Engineering Supervisor, CNS H. P. Smith, Design Engineer, CNS D. Brewer, Senior Engineer, Nuclear Services

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N. E. Estep, Nuclear Production Engineer, Nuclear Services G. Savage, Media Relations Specialist, General Office Staff OTHER P. R. Pappus, Director of Nuclear Operations, North Carolina Electric Membership Cooperative 1

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l ENCLOSURE 2 ENFORCENENT CONFERENCE

SUMMARY

On April 14, 1993, representatives from Duke Power Company (DPC) met with the NRC in the Region II Office in Atlanta, Georgia to discuss the failure to maintain the required availability of two independent Nuclear Service Water 1

(RN) System loops at the Catawba facility. The RN System was inoperable from j

August 1992 through February 25, 1993, due to several RN pump discharge valves i

being unable to open against RN pump discharge pressure because of improper torque switch settings on the valves. This problem was identified by the i

licensee on February 25, 1993, during the performance.of routine Inservice Testing activities on the RN pumps.

Upon further investigation, the licensee found that the system had been in various stages of degradation for approximately the past seven years.

Opening remarks, concerning the purpose of the meeting, were presented by Mr.

Luis A. Reyes, Deputy Regional Administrator, Region II (RII). Mr. George R.

Jenkins, Director, Enforcement and Investigation. Coordination Staff, RII, provided a discussion of the NRC Enforcement Policy. An overview of the issue i

and a discussion of the apparent violation were presented by Mr. Ellis W.

i Merschoff, Director, Division of Reactor Projects, RII.

Following these remarks, DPC gave a presentation, Enclosure 3, on the issue.

1 i

An introduction to DPC's presentation was given by Mr. M. S. Tuckman, Vice President, Catawba Nuclear Site (CNS). The formal presentation was given by l

Mr. J. S. Forbes, Engineering Manager, CNS. The presentation included an i

overview of the RN System, historical perspective and sequence associated with the event, root causes and corrective actions, and safety significance.

Closing remarks were provided by Mr. Tuckman.

Following a question and answer period, the NRC closed the meeting by thanking DPC for their presentation and stating that the presentation had served to enhance the NRC's understanding of the issue and DPC's corrective actions.

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I ENCLOSURE 3 ENFORCEMENT CONFERENCE NRC AND DUKE POWER COMPANY APRIL 14,1993 l

1 i

u ISSUES ASSOCIATED WITH t

CATAWBA NUCLEAR STATION I

l NUCLEAR SERVICE WATER SYSTEM 4

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CATAWBA NUCLEAR STATION DUKE POWER COMPANY PRESENTATION AGENDA l

l A.

INTRODUCTION M. S. TUCKMAN l

B.

NUCLEAR SERVICE WATER (RN)

J.S.FORBES SYSTEM OVERVIEW l

C.

SEQUENCE OF EVENTS J.S.FORBES 1.

OVERVIEW 2.

EVENT

SUMMARY

3.

HISTORICAL PERSPECTIVE D.

ROOT CAUSES AND CORRECTIVE ACTIONS J.S.FORBES 1.

INADEQUATE PROCEDURE IMPLEMENTATION 2.

INADEQUATE DESIGN / ENGINEERING VALVE TORQUE SWITCH SF1 TING (TSS)

DETERMINATION l

E.

SAFETY SIGNIFICANCE J.S.FORBES l

1.

PAST OPERABILITY ASSESSMENT 2.

DESIGN BASIS ACCIDENT TIMELINE 3.

SAFETY SIGNIFICANCE F.

CLOSING REMARKS M. S. TUCKMAN r

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LAKE WYLIE gg pg 54 69 18 389 29 O/G n

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VC TRAIN B a

M 10 DrG N690 IB N

DH 29 ESS -

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40 le 388 HEADER

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HEADER b[ 400 N 489 03 03 2A ESS _

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29A N G7A b

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SIMIPLIFIED FLOW O!AGRAM OF CATAWBA LAKE WYLIE Dc D C.---,

1A N

IA D/G NUCLEAR SERVICE WATER ( RN) SYSTEM IA 29 s

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NUCLEAd SERVICE WATER SY6 FEM (RN) 1 3

SUPPLIES COOLING TO BOTH SAFETY AND NON-SAFETY COMPONENTS j

SHARED SYSTEM BETWEEN U1 & U2 i

RN PUMP DISCHARGE VALVES INTERLOCKED WITH PUMP START ONE RN PUMP NORMALLY RUNS

- CROSS CONNECTS OPEN

- ANY RN PUMP CAN SUPPLY HEADER SUCTION:

LAKE WYLIE OR STANDBY N'UCLEAR SERVICE WATER POND LOADS:

D/G COMPONENT COOLING BUILDING SPRAY CONTROL ROOM VENTILATION EMERGENCY SIGNALS WILL START ALL FOUR (4) RN PUMPS AND ISOLATE CROSS CONNECTS DESIGN BASIS:

COOLDOWN ON 1 UNIT LOCA ON OTHER WITH CONCURRENT LOOP SINGLE FAILURE A

4

~

.m SEOUENCE OF MAJOR EVENTS

~1976 1979-80 1985 11/85 1986-88 VALVE PROCURED RN SYSTEM CNS STARTUP_

'LER 413/85'-68 FLUSHING i

  • 1RN69B AND
  • Provided valve
  • Valves Opened 1RN28A failed operating under full DP to fully open conditions to during testing valve

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  • Action:

manufacturer (shutoff head, Readjust TSS to max max flow)

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'g SEOUENCE OF MAJOR EVENTS 10/88 6/89 7/89 12/89 PIR-0-C88-0314 CORRECTIVE LER 413/89-29.

ACTIONS FOR PIR-0-C88-0314 1/2 RN148A failed to open

  • 1KC81B,
  • 1RN38B TSS 2KC56A during testing readjusted to Determined to e ACTIONS:

3.0 for open be incapable of

- Identified

- Recommmended opening against seat hardening max TSS for 56

  • 2RN28A and DP from issue for BIF BIF B/F valves 2RN38B TSS Engineering butterfly

- Readjusted incorrectly set study.

valves TSS for at 1.5 open i

  • Action:

1/2 RN148A

- DP tested Implement open inlets / outlets torque switch bypass mod i

s s

1

SEOUENCE OF MAJOR EVENTS

~

3/90 1991-92 8/92 1992-93

~2/25/93

'.m ACTIONS /GL89-10 LER 413/93-02

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e 1RN28A and

~per GL 89-10

. inoperable on criteria CNS-1; CNS-2 in (TSS ~2)

No mode

  • DP testing not performed 1-3 4

s 4

1

i EVENT

SUMMARY

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RN TRAINS SEPARATED l

"A" TRAIN SUPPLYING LOAD i

e RN PUMP 1B IWP TEST COMPLETED:

PUMP WAS SHUTDOWN e

RN PUMP 2B IWP TEST STARTED:

2RN38B FAILS TO OPEN RN PUMP 2B SHUTDOWN; RN PUMP 1B STARTED 1RN38B FAILS TO OPEN ENGINEERING EVALUATION:

"A" TRAlN PUMP

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DISCHARGE VALVES SUSCEPTIBLE TO SIMILAR PROBLEM e

UNIT 1 ENTERS T.S. 3.0.3; UNIT 2 IN NO MODE e

1/2 RN 28A AND 1/2 RN 38B RETURNED TO OPERABLE AND DP TESTED

SEOUENCE OF MAJOR EVENTS 1976 1979-80 1985 11/85 1986-88 t

VALVE PROCURED RN SYSTEM CNS STARTUP LER 413/85-68 4

FLUSHING

  • Provided
  • 1RN69B AND valve-
  • Valves Opened 1RN28A failed operating under full DP to fully open conditions to during testing valve manufacturer
  • Action:

(shutoff head, Readjust TSS to max flow) max l

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2

!!ISTORICAL TIME

  • Valves
  • Worked NRC IE BULLETIN
  • Purchased i

specified per w/MOVATS on 85-03 MOVATS standard preop test of equipment l

industry movats product

  • Review high (Gate, Globe practice -

pressure valve testing) flow, pressure applications to asure TSS meet operational requirements h'

ALL VALVES SET UP BASED ON TSS (WITHIN RANGE) 6l~

l4 NO SUITABLE. DIAGNOSTIC TESTING EQUIPMENT COMMERCIALLY AVAILABLE TO N'

l MEASURE TORQUE APPLIED TO VALVE STEM FOR BUTTERFLY VALVES i

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SEQUENCE OF MAJOR EVENTS 10/88 6/89 7/89 12/89 PIR-0-C88-0314 CORRECTIVE LER 413/89-29 ACTIONS FOR 1/2 RN148A PIR-0-C88-0314 failed to open

  • 1XC81B, during testing
  • 1RN38B'TSS 2KC56A readjusted to Determined to
  • ACTIONS:

3.0 for open be incapable o.

- Identified

- Recommmended opening against seat hardening max TSS for 56

  • 2RN28A and DP from issue for BIF BIF B/F valves 2RN38B TSS Engineering butterfly

- Readjusted incorrectly set study.

valves TSS for at 1.5 open 1/2 RN148A

  • Action:

- DP tested Implement open inlets / outlets torque switch bypass mod HISTORICAL TIME

  • Purchased GL89-10 ISSUED VOTES equipment
  • Measure torque / thrust delivered to valve

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  • Conduct DP testing lC BUTTERFLY VALVES SET UP DASED ON TSS (WITIIIN RANGE)

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'd NO SUITABLE DIAGNOSTIC TESTING EQUIPMENT COMMERCIALLY AVAILABLE TO N

MEASURE TORQUE APPLIED TO VALVE STEM FOR BUTTERFLY VALVES 1

SEQUENCE OF MAJOR EVENTS 3/90 1991-92 8/92 1992-93 2/25/93 ACTIONS /GL89-10 LER 413/93-02

  • 1RN28A and

No mode

  • DP testing not performed HISTORICAL TIME ER.C IEN 90-21
  • Issued on testing of with valve seat butterfly Fisher /POSISEAL hardening issue valves to conduct extensive out-
  • Based on
  • BARTS. system of plant B/F Catawba event, available, DPC valves testing LER 413/89-29 chooses not to pursue h

g BUTTERFLY VALVES SET UP BASED ON TSS (WITHIN RANGE) k NO SUITABLE DIAGNOSTIC TESTING EQUIPMENT 5l<

CNS PURCHASES VOTES

=l COMMERCIALLY AVAILABLE TO MEASURE TORQUE APPLIED 1/4 TURN SYSTEM, IN-SHOP TO. VALVE STEM FOR BUTTERFLY VALVES VALIDATION IN PROGRESS 1

INADEQUATE PROCEDURE IMPLEMENTATION ROOT CAUSE e

FIELD SETUP PROCEDURE FOR LIMITORQUE ACTUATORS NOT DETAILED ENOUGH; RESULTED IN TSS REVERSED ON 2RN28A AND 2RN38B (7/89)

SUBSEQUENT CORRECTIVE ACTIONS e

2RN28A AND 2RN38B RESTORED TO OPERABLE STATUS WITH FULL DP TEST CONDUCTED FOR EACH VALVE FIELD SETUP PROCEDURE VERIFIED TO HAVE e

BEEN REVISED IN 1991; AND PROVIDED ADDITIONAL DETAILED GUIDANCE INCLUDING GRAPHICS FOR TORQUE SWITCH IDENTIFICATION AND SETUP

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INADEQUATE PROCEDURE l

lMPLEMENTATION i

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SUBSEQUENT CORRECTIVE ACTIONS (continued)

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ASSESSED IMPLICATIONS FOR OTHER VALVES l

(LIMITORQUE, GL89-10 VALVES)

GATES AND GLOBES - ALL LIMITORQUE OPERATED VALVES HAVE BEEN SET UP ON MEASURED THRUST i

BUTTERFLY - BIF - (SAFETY FUNCTION TO i

OPEN) ALL HAVE EITHER BEEN DP TESTED I

OR O PER ATIO N AL CONDITIONS DETERMINED TO RESULT IN A SMALL DP

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( < 5 PSID)

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FISHER /POSISEAL - TSS FOR OPEN AND

]

CLOSE FUNCTIONS SET THE SAME 2

a ALLIS CHALMERS - (SAFETY FUNCTION j

TO OPEN) ALL VALVES SET UP AFTER j

PROCEDURE CHANGED l

4 i

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INADEQUATE DESIGN / ENGINEERING TSS DETERMINATION ROOT CAUSE i

i FAILURE OF PROVEN METHODOLOGY TO l

ESTABLISH ADEQUATE TORQUE VALUES (8/92) i l

l REASONS:

i i

TURBULENCE FACTOR POTENTIALLY NON-CONSERVATIVE l

POTENTIAL DEGRADED COMPONENT; RAW j

WATER APPLICATION i

j OPERATIONAL HISTORY N O T-FULLY CONSIDERED ACCEPTABLE DIAGNOSTIC EQUIPMENT NOT AVAILABLE TO FULLY VALIDATE SIZING j

FACTORS I

1/2 RN28A AND 1/2 RN38B EXCLUDED FROM

" TESTABLE UNDER DP" POPULATION ALL PUMP SUCTION AND DISCHARGE VALVES EXCLUDED DUE TO POTENTIAL-

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DAMAGE TO PUMP

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INADEQUA TE DESIGN / ENGINEERING TSS DETERMINATION SUBSEQUENT CORRECTIVE ACTIONS 1RN28A AND 1RN38B RESTORED TO OPERABLE STATUS WITH FULL DP TEST CONDUCTED FOR EACH VALVE 2RN38B REMOVED FOR LABORATORY DIAGNOSTIC TESTING l

REPLACED WITH FISHER /POSISEAL; DP TESTED l

j PLAN TO CONDUCT TESTS TO VALIDATE ROOT CAUSE l

ASSESSED IMPLICATIONS FOR OTHER VALVES (GL89-10 VALVES)

ISSUE LIMITED TO BUTTERFLY VALVES BIF - (SAFETY FUNCTION TO OPEN) ALL HAVE EITHER BEEN DP TESTED OR OPERATIONAL CONDITIONS DETERMINED i

TO RESULT IN A SMALL DP (< 5 PSID) i i

1 FISHER /POSISEAL - EXTENSIVE OUT OF i

PLANT TESTING DEMONSTRATES l

SIGNIFIC' ANT MARGIN IN~

SIZING i

CALCULATIONS ALLIS CHALMERS - (SAFETY FUNCTION i

TO OPEN) ALL VALVES SET TO MAXIMUM t

__....__..._.._._____.._.-_~..-...-_..__.-_..--_..-.~.__..._-___.____.-----.___-____-_,i

,II i

l INADEQUATE DESIGN / ENGINEERING TSS i

DETERMINATION l

PLANNED CORRECTIVE ACTIONS j

e EVALUATE APPRO PRI ATENESS OF i

TURBULENCE FACTORS EPRISTUDY f;

STUDY WITH FISHER /POSISEAL

)

e CONSIDER OPERATIONAL HISTORY i

CONDUCT SPECIAL TESTING ON 2RN38B j

(REMOVED)

VALIDATE ASSUMPTIONS VALIDATE ROOT CAUSE i

j e

DETERMINE LONG-TERM DISPOSITION OF RN j

PUMP DISCHARGE VALVES i

e REEVALUATE TESTING PLAN FOR GL 89-10 VALVES

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^

l PAST OPERABILITY ASSESSMENT PAST OPERABILITY TIMEUNE RN PUMP STARTUP (DISCH. VLV) 1/85 11/85 7/89 8/92 2/93 1A 1.5 3.0 2.0 2.0 3

(IRN28A)

M.g.

20 o 2A 1.5 1.5 3.0 (2RN28A) liddddj$W$W@lHHdjWl$jldlhWlEllililill@l IHHlWW@lll$llNH@HH@HlHElllHMlWWQj@llHWMlWlHHNlll@lllWHHHlll@@hWWlWlWl@llhWWWW@HHWlWldlWllllllllHQ l

18 1.5 1.5 3.0 2.0 2.0 (IRN388)

"'!""?P"l!$ "f W""T""F"i !M'!?

lM 20 deg.

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28 1.5 1.5 3.0 (2RN388)

$$ll@Hl@MQMMM@HlllMl5 llglgMgMl i

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OPERABLE lllll lNOPERABLE g

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DESIGN BASIS ACCIDENT LINE (NINUTES) i T=0 T=5 TO 6 T=10 T=18 T=25 l

1 1

1 I

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'N' ;

o ASSUME:

  • D/G FAILS

- LOCA NO RN FROM

- 1A D/G W/O RN 2B RN PUMP

- LOOP

- MONITOR LT PNL

- IB D/G (CALC.)

DISCHARGE

- 2A D/G FAILS

- ANNUNCIATOR PNL

- 2B D/G VALVE

- 2B D/G STARTS

- 1A D/G/ STARTS

- 1B D/G STARTS TO RN STRUCTURE 2B D/G AND INITIATES I

ECCS l

l I

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'B' TRAIN ECCS OPERATING NO ECCS b

REESTABLISH m

m m

a' ECCS ASSUMPTIONS:

UNIT 1 UNIT 2 (NON-ACCIDENT. UNIT)

(ACCIDENT UNIT)

  • BOTH D/G START
  • NO RN
  • D/G 2A FAILS, (SINGLE FAILURE)
  • D/G 2B STARTS
  • NO RN i

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i SAFETY SIGNIFICANCE l

1 i

j l.

DESIGN BASIS ACCIDENT CONDITIONS

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DESIGN BASIS ACCIDENT CONSIDERED AS MOST j

ENVELOPING IN CONSEQUENCES:

UNIT 2 LARGE j

BREAK

LOCA, LOSS OF OFFSITE
POWER, DETERMINISTIC FAILURE OF 2A D/G AS MOST LIMITING SINGLE ACTIVE FAILURE i

I; j

DESIGN BASIS EXCEEDED f

CONTAINMENT INTEGRITY MAINTAINED l

l l

j 10CFR100 LIMITS NOT EXCEEDED i

i ASSUMPTIONS:

j

-ILRT RESULTS BASED ON AS FOUND TESTING i

j

-TID-14844 SOURCE TERM AND SOURCE TERM TIMING l

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- ASSUMES FULL CORE MELT @ T=0

- NO AC POWER TO ESF FOR 15 MINUTES

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k SAFETY SIGNIFICANCE II.

RISK PERSPECTIVE (PRA) e PROBABILITY OF DESIGN BASIS ACCIDENT SCENARIO (LBLOCA, LOOP, FAILURE OF 2A D/G)IS STATISTICALLY INSIGNIFICANT CMF INCREASED BY A FACTOR OF ~2 DURING 7 e

MONTH PERIOD (DUE TO LOSS OF NUCLEAR SERVICE WATER INITIATOR RESULTING IN REACTOR COOLANT PUMP SEAL LOCA)

... -.. - -.. -. ~. - -.

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.E BlF Calculation Method Comparison i

i 6

Parameter Original Sizing 89-10 Set-up Difference l

(Ft-Lb) l Bearing friction -

0.08 0.1 230 coefficient j

Seating / unseating 16 to 19 25 420 to 631 coefficient Hydrostatic Uncertain Assumed even 104 torque though not present Total dynamic No turbulence Turbulence factor 350 (Applies to factor to account for dynamic torque l

piping only) l configuration (1.2) l Instrument None 10%

300

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l Tolerance &

i Repeatability i

Set-up Margin None 10%

300 j

DP Margin over 115-95=20 psid 115-95=20 psid 200 (Added l

actual achievable margin to both methods)

Total at Shaft 1354 Ft-Lb Total Actuator 59 Ft-Lb l

l L

Original Set-up Range:

Minimum of 1.5 = 130 Ft-Lb l

Maximum of 3.0 = 254 Ft-Lb 89-10 Set-up Range:

Minimum of 157 Ft-Lb Maximum of 171 Ft-Lb l

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

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