ML20038C576

Final Deficiency Rept Re Linear Indications in Electrical Cable Tray Seismic Support Clips 88R1,previously Reported 801223.Clips 88R1 & 88R2 Found in Testing to Be Structurally Sound & Adequate for Intended Use

ML20038C576
Person / Time
Site:	Waterford
Issue date:	12/03/1981
From:	Aswell D LOUISIANA POWER & LIGHT CO.
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
10CFR-050.55E, 10CFR-50.55E, W3K-81-04335E, W3K-81-4335E, NUDOCS 8112110242
Download: ML20038C576 (7)

Text

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i_Q UISI AN A / W DELARONDE STREET P OWE R & LiG H T/ P O box 6008

• NEW ORLEANS. LOutSIANA 70174 * (504) 366 2345 UT OYsbsYE D L ASWELL December 3, 1981 u, p,,o.,,t%,, p.

W3K-81-0433 Nt gf j"<(x, /\Q-3-A35.07.21 N[,- ,;n. *'<y.

Mr. K. V. Seyfrit, Director, Region IV l' -

U. S. Nuclear Regulatory Commicsion [~)[ ((tIfjf'[5[k'" ~

E. 7 Office of Inspection and Enforcement g]

2 O['[g g -gl 611 Ryan Plaza Drive, Suite 1000 -

s Arlington, Texas 76012 '

- *8'""*"% oD" M

%/ Ni

Subject:

Waterford SES Unit No. 3 N // a -sk Docket No. 50-382 Final Report of Significant Construction Deficiency No. 21

" Linear Indications in Electrical Cable Tray Seismic Support Clips (88Rl)"

Reference:

LP&L Letter to USNRC W3K-80-0037 dated December 23, 1980

Dear Mr. Seyfrit:

In accordance with the requirements of 10CFR50.55(e), we are hereby providing two copies of the Final Report of Significant Construction Deficiency No. 21, " Linear Indications in Electrical Cable Tray Seismic Support Clips (88Rl)."

If you have any questions, please advise.

Very truly yours, Q L/

D. L. Arvell DLA/LLB/grf Attachment cc: 1) Director Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 (with 15 copies of report)

2) Director Of fice of Management ,. ,

l Information and Program Control i U. S. Nuclear Regulatory Commission Washington, D. C. 20555 (with I copy of report) gf '/

l 8112110242 811203

{DRADOCK 05000382 PDR

LOUISIANA POWER & LIGHT COMPANY WATERFORD SES UNIT No. 3 Final Report of Significant Costruction Deficiency No. 21 Linear Indications in Electrical Cable Tray Seismic Support Clips (88Rl)

Reviewed by:, 4 / 2/eM R/J." Milhiser - fite Man (ger Date Reviewed by: ~ I.'L. Wills - Project Superintendent

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M Date m l Reuteued by: N< v fb?'!! k  ?'!/,*f/ l} ~Date l~ h/

J Hart - Project Licensip Engineer Reviewed by: ,

c>fMc,M / s/s !,( /

J 4 dB'r61n - ES'St~1)rpjsct Engineer / , Da t'e Q

Reviewed by:  ! '

o MM.! / '/- I/

J.,Gutierrez - Q. A. Site,, Supervisor Date December 1, 1981 I

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FINAL REPORT SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 21 LINEAR INDICATIONS IN ELECTRICAL CABLE TRAY SEISMIC SUPPORT utIPS (88Rl)

INTRODUCTION This report is submitted pursuant to 10CFR50.55(e). It describes deficiencies in the base metal of the 88R1 Electrical Cable Tray Seismic Support Clips. The problem was evaluated to determine whether the scope must be expanded to in-clude 88R2 type clips. The problem was defined as " reportable" as a result of the extensive engineering investigation which was conducted. This problem is considered reportable under the requirements of 10CFR50.55(e). To the best of our knowledge, this problem has not been identified to the Nuclear Regulatory Commission pursuant to 10CFR21.

DESCRIPTION fischbach & Moore, Inc., detected indications (laminationu) on the edges of the 88R1 clips during preparatory weld activities and after welding operations. Non-conformance Report Numbers W3-600, W3-620, W3-628 and W3-710 were issued to docu-ment and disposition this condition. Nonconformance Report W3-710 supercedes the other previously issued Nonconformance Reports.

These clips were manufactured from A36 material, Heat Number A20238, and supplied by Peden Steel through Purchase Order No. NY-403509. The Ebasco Material Receiv-ing Report No. 701770 indicates that a total of 232 88R1 and 318 88R2 clips of this heat number were received. Approximately 400 88R1 and 88R2 clips from this heat and a replacement heat have been installed in the Reactor Auxiliary Building.

Examination of the extent of the laminations was performed by UT examining ten (10) randomly selected 88R1 clips per Peabody Procedure 3.22.A.2, Rev. O, Amendment 1903-2. The results of this examination are documented on Revision 2 of Noncon-formance Report W3-710. To study the behavior of the laminations during welding l operations, a weld bead of the same size and configuration as used during installa-tion was deposited on the clips with additional UT performed subsequent to deposit-

, ing the weld metal. This data was submitted for technical evaluation. Results of an analytical structural analysis show that certain characteristics of the lamina-tion manifested in one of the clips are not considered acceptable for both 8" and 6" square tubing section hangers and also unacceptable for some wide flange section (or W shape) hangers under seismic loading conditions. Therefore, it was concluded that further investigation was required to determine the performance of the clips under actual loading conditions.

SAFETY IMPLICATIONS Ebasco Design Engineering's evaluation has concluded that under certain loading conditions, the 88R1 clips are considered unacceptable. Therefore, if this de-

! ficiency is left uncorrected, some of the clips would conceivably be unable to support the safety-related cable trays during a seismic event, potentially result-

ing in failure of the trays with subsequent damage to the cables in the trays as l well as falling on and damaging other safety-related equipment. This will cause degradation of safety-related systems.

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CORRECTIVE ACTION Construction Technology Laboratories (CTL), a division of the Portland Cement Association, has concluded load tests on seven (7) cable tray hanger mockup as-semblies. .This work was authorized by Purchase Order W3-12024 dated June 9, 1981. The clip connection details used to fabricate the mockups represent the connection details actually used in the cable tray supports; they are the same as shown on Ebasco Design Drawing LOU-5817G-695S06. The mockup assemblies were fabricated using 88R1 clips containing laminations representative of the conditions found at the Site. Specified tension and shear loads were applied by CTL to each specimen. Strains and brittle coating crack patterns on the vertical legs of the clip angles were recorded. The tests were performed with the most susceptible material subject to the most critical load conditions. The tests revealed the following results:

1) All test specimens sustained the specified loads with no visual signs of distress.

2) Maximum strain at peak loads measured with Gage 2A ranged from 440 millionths to 940 millionths. (The latter value corresponds to a stress of approximately 27 ksi which is within 90 percent of the yielding strength for A-36 material; this is acceptable under SSE [ Safe Shutdown During Earthquake] design con-ditions.)

3) Brittle coating applied to end surfaces of vertical legs of each clip angle did not produce any definite indication of strain through the leg thickness.

4) Strain gages mounted horizontally on ends of the vertical legs of each clip angle indicated only negligible strains through the leg thickness ^during load tests.

Based on the above findings, it is concluded tha: the 88R1 and 88R2 clips are structurally sound and adequate for their intended use.

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LOUISIANA POWER & LIGHT COMPANY WATERFORD SES UNIT NO. 3 Final Report of Significant Costruction Deficiency No. 21 Linear Indications in Electrical Cable Tray Seismic Support Clips (88Rl)

Reviewed by:.. 4 R/J.' Milhiser - flite Man (ge:

/2 4/k Date Reviewed by:

f.'L. Wills - Project Superintendent

/h/M' Date Reviewed by: __ / 4[/I J Hart - Project Licensip Engineer

_ [ M5 [/*:/t /2 -Date /~ 8[

Reviewed by: m /p/MM / i_/i /4 /

J d ~'r61n B - ES'S M rpjsct Engineer / ,Dat'e

.r y Reviewed by: k/ -

e M[A5 - '/ a J.,Gutierres - Q. A. Site, Supervisor

, Date December 1, 1981 9

. .]

FINAL REPORT SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 21 LINEAR INDICATIONS IN ELECTRICAL CABLE TRAY SEISMIC SUPPORT CLIPS (88Rl)

INTRODUCTION This report is submitted pursuant to 10CFR50.55(e). It describes deficiencies in the base metal of the 88R1 Electrical Cable Tray Seismic Support Clips. The problem was evaluated to determine whether the scope must be expanded to in-clude 88R2 type clips. The problem was defined as " reportable" as a result of the extensive engineering investigation which was conducted. This problem is considered reportable under the requirements of 10CFR50.55(e). To the best of our knowledge, this problem has not been identified to the Nuclear Regulatory Commission pursuant to 10CFR21.

DESCRIPTION Fischbach & Moore, Inc., detected indications (laminations) on the edges of the 88R1 clips during preparatory weld activities and after welding operations. Non-conformance Report Numbers W3-600, W3-620, W3-628 and W3-710 were issued to docu-ment and disposition this condition. Nonconformance Report W3-710 supercedes the other previously issued Nonconformance Reports.

These clips were mancfactured from A36 material, Heat Number A20238, and supplied by Peden Steel through Purchase Order No. NY-403509. The Ebasco Material Receiv-ing Report No. 701770 indicates that a total of 232 88R1 and 318 88R2 clips of this heat number were received. Approximately 400 88R1 and 88R2 clips from this heat and a replacement heat have been installed in the Reactor Auxiliary Building.

Examination of the extent of the laminations was performed by UT examining ten (10) randomly selected 88R1 clips per Peabody Procedure 3.22.A.2, Rev. O, Amendment 1903-2. The results of this examination are documented on Revision 2 of Noncon-formance Report W3-710. To study the behavior of the laminations during welding operations, a weld bead of the same size and configuration as used during installa-tion was deposited on the clips with additional UT performed subsequent to deposit-ing the weld metal. This data was submitted for technical evaluation. Results of an analytical structural analysis show that certain characteristics of the lamina-tion manifested in one of the clips are not considered acceptable for both 8" and 6" square tubing section hangers and also unacceptable for some wide flange section (or W shape) hangers under seismic loading conditions. Therefore, it was concluded that further investigation was required to determine the performance of the clips under actual loading conditions.

SAFETY IMPLICATIONS Ebasco Design Engineering's evaluation has concluded that under certain loading conditions, the 88R1 clips are considered unacceptable. Therefore, if this de-ficiency is left uncorrected, some of the clips would conceivably be unable to

' support the safety-related cable trays during a seismic event, potentially result-ing in failure of the trays with subsequent damage to the cables in the trays as well as falling on and damaging 'ther safety-related equipment. This will cause degradation of safety-related systems.

CORRECTIVE ACTION Construction Technology Laboratories (CTL), a division of the Portland Cement Association, has concluded load tests on seven (7) cable tray hanger mockup as-semblies. This work was authorized by Purchase Order W3-12024 dated June 9, 1981. The clip connection details used to fabricate the mockups represent the connection details actually used in the cable tray supports; they are the same as shown on Ebasco Design Drawing LOU-5817G-695S06. The mockup assemblies were fabricated using 88R1 clips containing laminations representative of the conditions found at the Site. Specified tension and shear loads were applied by CTL to each specimen. Strains and brittle coating crack patterns on the vertical legs of the clip angles were recorded. The tests were performed with the most susceptible material subject to the most critical load conditions. The tests revealed the following results:

1) All test specimens sustained the specified loads with no visual signs of distress.

2) Maximum strain at peak loads measured with Gage 2A ranged from 440 millionths to 940 millionths. (The latter value corresponds to a stress of approximately 27 ksi which is within 90 percent of the yielding strength for A-36 material; this is acceptable under SSE [ Safe Shutdown During Earthquake] design con-ditions.)

3) Brittle coating applied to end surfaces of vertical legs of each clip angle did not produce any definite indication of strain through the leg thickness.

4) Strain gages mounted horizontally on ends of the vertical legs of each clip angle indicated only negligible strains through the leg thickness'during load tests.

Based on the above findings, it is concluded that the 88R1 and 88R2 clips are structurally sound and adequate for their intended use.