ML17266A359

Final Deficiency Rept Originally Reported on 800325 Re Defective Hydramotor Actuators for Dampers & Louvers.Caused by Mfg from Incorrect Matl.Dampers Reworked & Retested. Dampers & Louvers to Be Tested in Preoperational Program

ML17266A359
Person / Time
Site:	Saint Lucie, Three Mile Island
Issue date:	10/31/1980
From:	Robert E. Uhrig FLORIDA POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
10CFR-050.55E, 10CFR-50.55E, IEB-80-09, IEB-80-9, L-80-365, NUDOCS 8011140059
Download: ML17266A359 (6)

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t.o. BOX 529100 MIAMI.F L 33152

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FLORIDA POVIER 5 LIGHT COMPANY October 31, 1980 L-80-365 N. James p. O'Reilly, Director, Region II Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission .

101 Harietta Street, Suite 3100 Atlanta, Georgia 30303

Dear Hr. O'Reilly:

Re: St. Lucie.Unit 2 Docket No. 50-389 Dam er Actuators  !

American Marming 5 Ventilating, Inc. (AWV) has.previously notified the HRC of deficiencies in their damper/louver actuators. On Harch 25, 1980 (L-80-103)

Florida Power 8 Light Company {FPL) submitted an interim deficiency report, pursuant to 10 CFR 50.55{e) requirements, advising the NRC ef the impact of those deficiencies on St. Lucie Unit 2 damper/'louver actuators. Additional information was provide'd to you in a June 30, 1980 letter {L-80-208) .which also stated that a final deficiency report would be submitted by October 31, 1980. Accordingly, a final report is attached for your review.

In a letter to the Director of Reactor Construction. Office of Inspection and Enforcement, in response to IE Bulletin 80-09 (Hydramotor Actuator Deficien-cies), FPL reported the existence of 47 .damper/louver actuators that could have contained the deficiencies reported by .AMV. During the preparation of the final report, it was determined that the correct nImIber of damper/louver actuators is 45, as initially reported to you on torch 25. 1980.

Very truly yours,

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Vice President Advanced Systems c Technology REU/TCG/ah

'ttachments cc: Harold F. Reis. Esquire of Inspection and Enforcemebt

'irector U. S. Nuclear Regulatory Commission Mas ington, 'D. C. 20555

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FINAL DEFICIENCY REPORT DAMPER'CTUATORS Name of Station: St. Lucie P1ant - Unit 2 Owner:, Rorida Power 8 Light Company Architect/Engineer: Ebasco Services, Incorporated Date BRC Notified: February 21, 1980 Interim Report Filed: Harch 25, 1980 Final Report Fi1ed: October 31, 1980

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SUMMARY

American Razming t'* Ventilating, Znc. (A%V) has notified the NRC, pu suant to 10CFR 21, of potential de"ects in some hydromotor actuatoxs fox dampers and louvexs, puxchased by AWV from XTT General Controls of Glendale, California. These potential defects involved incorrect material in' certain spring used in some actuators and the selection nomographs used for sizing certain actuators, which could be interpreted incorrectly.

The interim report (L-80-103, dated March 25, 1980) identified 45 dampezs .

and louvers as heing affected. Please note that L-80-241, dated July 28; 1980, incorrectly quantified the number affected as 47. The 19 dampers identified in the interim report as being placed on hold in the vendor's shop,, have been retestect and reworked as necessary by XTT and subsequent-ly shipped to the site for installation. AHV has evaluated the remaining 26 dampers and Iouvers (24 dampezs and 2 louvers) shipped to St Lucie site before -the deficiency was detected, using statistical data provided by XTT. Out of 26 dampers and louvers four dampers require spring re-..

placement; five dampexs require a spring adjustment, 15 dampers have been evaluated as meeting the torque requirements and corrective actions he perfoxmed on the two louvezs.

vill Per the requirements of 2.0CPR50.55(e) the events are deemed reportable.

By telephone PPL notified the NRC on Pebruaxy 21, 1980, and an interim

-report was submitt d on Haxch 25, 1980. This final report is submitted, to advise the NRC of the do'scription of the deficiency and the correct-ive actions that vill I

be taken.

. XX. DES CRZPTZON ZTT General Controls of Glendale, Califorziia, a subcontractor supplying nctuators to Amexican Haaaing & Ventilating Xnc., notified American

$ Tarnmg of the existence of a'material deviation in a certain spring in "ome hy'dramotor actuatozs. One spring, XTT Part No. 17443A, used in some NH91, 92, 95, 96 and 98 milliampere hydzamotor actuators has been discovered (in December, 1979) to be manufactured from an incorrect material. Zt does not possess the designed strength -and will, upon ac-tuation of a greater than three inch stroke, take a permanent set. This r sul'ts in a decreased force'utput of approximately 160 lbs. at all com-pressed positions. Nhen these aforementioned actuators are subjected elecuical input control signal of zero,. the actuatox output does not to'n develop the published. force when the output shaft is moved to its full position (i.e., fully closed or fully opened)'.

The dampers (D) impacted by the above spring material deviation are as follows:

Shi oed to Site before Deficiency was Detected D-14 D-30 D-16 D-31 D-29 D-32 Placed on Hold D-8A D-9A D-15 D-34 D-36 D-8B D-9B , D-33 D-35

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On February .5, 1960 American Narming received a letter from XTT General Controls stating that American Rarming purchased ITT General series or NH90 series hydramotor actuators which may have been se-Controls'H90 lected or sized by using the "Selection Nomographs" on XTT's application form 0608.1067.2. This "Selection Nomographs" problem was discovered, by XTT General Controls in the course" of their investigation concerning the spring material deviation problem. XTT General Controls advised American arming that the subject nomographs could be interpreted incorrectly.

The forces that are derived from the chart represent the actual spring or hydraulic forces only, i.e., the effects of friction or residual forces axe not included. These actuators could have about, 100 lbs.

hydrau-'9.c of friction and an additional 40 lbs. of residual hydraulic pressure.

. This means that the e was a possibility that, the XTT General series actuators supplied with. American Warming dampers and louvers Controls'K90 auld not meet the specified safety factors with respect to thrust deli-vered to ths damper assembly.

The dampers (D) and louvers {L) impacted by the above nomograph problem Mclude the 15 dampers listed above plus the fol3.owing 30 additional.

ed to Site before Deficien 1'hia was Detected D-7A D-18 D-27 D-73 D-19 D-28 D-12A D-20 D-39 D-12B D-21 D-40 D-13 D-22 D-17A D-23 D-.173 D-24 2L-7A $ Mote: These louvers were incorrectly 2L-7B 'I labled 2L-8 and 2L-ll in lette I-80-103 Placed on Hold D-1 D-6A D-2 D-1IA D-6B'-3 D-4 -. D-llB D-5A D-SB

.All the above dampers and louvers are safety related.

XXX COR~~CTXVE ACTION The 19 dampers identified as "placed on hold" have been reworked and.

retested by XTT General Controls and now meet all performance recpxire-ments.

The XTT General Controls has performed an actual test program with a large number of actuators (normal voltage, single phase) to determine thei minimum output forces. Actuators produced prior to December 1979 were included in the samples.

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Their Engineering Report no. 721.80.118 "AH/HH 90 Series Actuatoxs>>

Net Output Forces" dated July 15, 1980 is bossed on a statistical analysis of these test data. A copy of the. report was sent to the.

HRC's Office of Inspection and Enforcement by American Harming &

'Ventilating, Inc. The actuator farce data contained in this report included the lover force produced by the incorrect material'number

. 1 spring. Based on this statistical approach the report concluded that at an 808 confidence level, 98% of the units would have output forces at, or in excess of a statistical minimum..'This statistical minimum of the output forces was compared to each recpxired actuator l'-7A output force including .safety factors.

'ased on the At& has concluded that, E l

1) The following 15 dampers with'ITT actuators meet the specified

,.minimum torque xecpzixements:

D 18 D-24 D-73 D-14 D-16 D 19 D-20 D-21

- '-40.

D-39 D-17A D-22 D-17B D-23

2) The following 5 dampers recruire -a spring adjustment that could be performed without removing the actuator from damper. Access to these dazpers would. be available for later spring adjustment woxkf h W D-13 D-29 D-30 D-31 D-32

3) The fa9.l"return springs of the following 4 damper actuators have to be replaced to provide the required torque. Access to these dampers would also be available so that recpxixed work may be perfoxmed by

.A%V.

D-12A D-123 '-27 D-28

4) The following two louver actuators have to be either reworked or

-replaced to ensure the required output forces.

2L-7A~ 2L-7B Xn preparation for implementation of these. changes, St Lucie Unxt 2

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Site construction has been notified of the re~ired work on the dampexs and louvers

,Note that the above listed dampexs and louvers were already shipped to the site before the deficiency was detected.

As part of the plant's preoperational testing program, all the safety x lated dampexs and louvars will be test d prior to fuel load. to assuxe proper system operation.

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TV SAZETY Z~IPLZCATIONS The safety of operation of the nuclear power plant could have been adversely affected sometime throughout the expected lifetime of the

.plant, if the damper actuators that require spring adjustment or

-replacement were to have remained uncorrected.

V CONCLUSION Corrective action as indicated in Section XZZ of this report will be underta3cen by the vendor {AHV) at the St Lucie site. This closes out this item for St Lucie Unit 2 as regards both 10CFR50.55(e) and ZZ Bulletin 80-09.