ML20040B814

Final Rept of Significant Const Deficiency 30 Re Selection of Fastener Matl for Motor Control Ctr & Switchgear Bus Connections Resulting in Overtorquing of Fasteners.Repairs Completed on 811218 Per Ebasco Nonconformance Rept W 3-2750

ML20040B814
Person / Time
Site:	Waterford
Issue date:	01/18/1982
From:	Mclendon G LOUISIANA POWER & LIGHT CO.
To:	Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
10CFR-050.55E, 10CFR-50.55E, W3K82-0019, W3K82-19, NUDOCS 8201260436
Download: ML20040B814 (3)

Text

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_0 UISIA N A , a OnAnoNot Sm m 4( p l T H.

E R & L l G H T! P O BOX 6008* NEW ORLEANS. LOUISIANA 70174 * [504) 366 2345 NN f4 5 SYSif M

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' CEWGD January 18, 1932

, \ G D McLENDON y g G JgQ>- .g '

Senior Voce President

-4 ngen;ctrm en:21 I W3K82-0019

'. Sea iumsts it / Q-3-A35.07.30 3 120 /'

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to to Mr. John T. Collins, Regional Administrator, Region IV U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 Arlington, Texa s 76012

SUBJECT:

Waterfrrd SES Unit No. 3 Docket No. 50-382 Final Report of Significant Construction Deficiency No. 30

" Change Out' of ASTM A193 S.S. Bolts on Motor Control Center Bus Bars"

Reference:

LP&L Letter to USNRC W3K81-0400 dated November 4, 1981

Dear tir. Collins:

In accordance with the requirements of 10CFR50.55(e), we are hereby providing two copies of the Final Report of Significant Construction Deficiency No. 30,

" Change Out of ASTM A193 S.S. Bolts on totor Control Center Bus Bars".

I f you have aay questions, please advise.

Very truly yours, CDMcL:LLB:ncd cc: II D i re c tor Of fice of Inspection & Enforcement U. S. Nuclear Regulatory Commission W a sh ing t on , D. C. 20555 (with 15 copies of report)

2) Director 0ffice of Management Information and Program Control U. S. Nuclear Regulatory Commission s

) '

Washignton, D. C. 20555 (with I copy of report) haf i

8201260436 920118 PDR ADOCK 05000382 S PDR

LOUISIANA POWER & LIGHT COMPANY WATERFORD SES UNIT No. 3 Final Report of Significant Construction Deficiency No. 30 Change Out of ASTM A193 S.S. Bolts on Motor Control Center Bus Bars Revicued by /*, ., '. s v- ~' du r22, /YP/

R. J. Milhiser - Site Manager D' ate Revieve by .# f

'J. L. Wills - Project Superintendent h E{}&[' Date Reviewed by

[c cnt cz,. th)ts,.  ?),I -2 /

'O J.' Hart - Project Licensing Engineer

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Date f

Reviewed by \ ] 14.tv ( s 'D LUd

'N ' ! _ ___.--

E /l lh gg,J % *ierrez - Q. A. Site Supervisor Datfe Reviewed by' i

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, /2 3/ f/

W.,taeger - Sr.'Kesident Engineer ' Date

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Reviewed by \ w .O/3 h,uxm J,;',EeBruin - ESSE Project Engineer

/ t/ Datef

/

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December 22, 1981

I i

4 FINAL REPORT SIGNIFICANT CONSTRUCTION DEFICIENCY No. 30 CHANGE OUT OF ASTM A193 S.S. BOLTS ON MOTOR CONTROL CENTER BUS BARS i

INTRODUCTION j This report is submitt.ed pursuant to 10CFR50.55(e). It describes a deficiency l i in the selection of fastener material for the MCC and switchgear bus j l connections which resulted in overtorquing of the fasteners. This problem is

considered reportable under the requirements of 10CFR50.55(e). To the be s t of

! our knowledge, this problem has not been identified to the nuclear Regulatory Commission pursuant to 10CFR21.

l DESCRIPTION OF DEFICIENCY The deficiency occurred during corrective action rework associated with Noncon-j formance Report W3-2250, issued to document the rusting of the fasteners on the MCC and switchgear bus connections. The disposition required that the rusty i bolt s be changed out with ASTM A193 material, but the grade was not specified.

During procurement of the replacement bolts, ASTM A193, Class 1:B8 bolts were specified based on corrosion resistance considerations. Structural adequacy

requirements were not considered at this time.

The initial installation utilized SAE GR 5 (or better) steel, torqued to 40 +

ft. lbs. in accordance with Drawings 5817-2701 through 2703. This type cf bolt has a yield strength of 92 KSI (minimum) and a tensile strength or 120 KSI (minimum).

The ASTM A193, Class 1:BS bolts have a yield strength of 30 KSI (minimum) and a tensile strength of 75 KSI (minimum).

At the time of the Interim Report, it was stated that the six (6) MCC's addressed were considered to be safety-related. Subsequent investigation revealed that two (2) of the MCC's listed, (3A411 and 3B411) are non-safety.

1 It has been verified that only four (4) of the MCC's listed are safety-related 4

as follows: 3A312, 3B311, 3B312, and 3B313.

SAFETY IMPLICATIONS If a degraded type of bolt were used on the 480V MCC bus bar bolted connections, the equipment would not satisfy the seismic requirements of the specification and would be incapable of performing its required function during and after a design basis earthquake.

CORRECTIVE ACTION Completion of repairs was accomplished on December 18, 1981 and performed in accordance with Ebasco Engineering's disposition detailed on Nonconformance Report W3-2750. The repairs were conducted at the Waterford 3 Site and were i tspected and documented by Louisiana Power & Light.

1 i

l

LOUISIANA POWER & LICllT COMPltNY t

WATERFORD SES UNIT NO. 3 ,

Final Report of Significant Canstruction Deficiency No. 30 l t

I Change Out of ASTM A193 S.S. Bolts on Motor Control Center Bus Bars  !

Reviewed by f k. ,6 w "* /).sof2, /f}V R.J.Miihisy-SiteManager D' ate i Revieve1 by , h / E f / J 6f ,[ [ I 8'J. L. Wills - Project Superintendent #

Date f Revieuet by _

Seonf. pie.b)/gs, $ } . [ Z .2.1 VJ .' IT t - Project Lidensing Engineer Date Revieve by_ h ,

2I

' terrez - Q. A. Site Supervisor Dade

( (J Reviewed byl L .

OL /2 / /

W./laege/ 'Sr. Yesident Engineer 'Date -[

Reviewed by . tO/9 [h u/_ / t/2. I 8/

Ifatd JpeBruin-ESSEProjectEngineer /

f December 22,. 1981 i:

i

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- -. - _ _ _ _ _ _ ?. .

i FINAL REPORT i , , SIGNIFICAdT CONSTRUCTION DEFICIENCY NO. 30 CHANCE OUT OF ASTM A193 S.S. BOLTS ON MOTOR CONTROL CENIER BUS BARS l

j INTRODUCTION This report is submitted pursuant to 10CFR50.55(c). It describes a deficiency in the selection of fastener material for the MCC and switchgear bus

! connections which resulted in overtorquing of the fasteners. This problem is l considered reportable under the requirements of 10CFR50.55(c). To the best of j our knowledge, this problem has not been identified to the Nucicar Regulatory Commission pursuant to 10CFR21.

1 1

DESCRIPTION OF DEFICIENCY I

The deficiency occurred during corrective action rework associated with Noncon-j formance Report W3-2250, issued to document the rusting of the fasteners on the i MCC and switchgear bus connections. The disposition required that the rusty

] bolts be changed out with ASTM A193 material, but the grade was not specified.

]

During procurement of the replacement bolts, ASTM A193, Class 1:BS bolts were j specified based on corrosion resistance considerations. Structural adequacy requirements were not considered at this time.

I j The initial installation utilized SAE CR 5 (or better) steel, torqued to 40 +

i ft. Ibs, in accordance with Drawings 5817-2701 through 2703. This type of bolt I has a yield strength of 92 KSI (minimum) and a tensile strength of 120 KSI l (minimum).

I

! The ASTM A193, Class 1:B8 bolts have a yield strength of 30 KSI (minimun) and a tensile strength of 75 KSI (minimun).

]

i l At the time of the Interim Report, it was stated that the six (6) MCC's

addre'ssed were considered ~to be safety-related. Subsequent investigation

! revealed that two (2) of the MCC's listed, (3A411 and 3B411) are non-safety.

l It has been verified that only four (4) of the MCC's listed are safety-related as follows: 3A312, 3B311, 3B312, and 3B313, i

! SAFETY IMPLICATIONS 1

j If a degraded type of bolt were use.1 on the 480V MCC bus bar bolted connections, the equipment would not satisfy the scismic requirements of the specification and would be incapable of performing its required function during and af ter a design basis earthquake.

CORRECTIVE ACTION Completion of repairs was accomplished on December 18, 1981 and performed in accordance with Ebasco Engineering's disposition detailed on Nonconformance Report W3-2750. The repairs were conducted at the Waterford 3 Site and were inspected and documented by Louisiana Power & Light.

_ _ - J