ML20058E013
| ML20058E013 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 07/19/1982 |
| 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, W3K82-0424, W3K82-424, NUDOCS 8207270466 | |
| Download: ML20058E013 (3) | |
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I OUISIANA P O W E R & L 1 G H T! P O DOX 6008. NEW ORLEANS LOUISIANA 70174
,4a ouAnoNoE s1nar (5041 366 2345
TEN ESE ut July 19, 1982 G. D McLENDON Senior Vice President W3K82-0424 Q-3-A35.07.59 Mr. John T. Collins, Regional Administrator, Region IV U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012
Subject:
Waterford SES Unit No. 3 Docket No. 50-382 Final Report on Significant Construction Deficiency No. 59
" Reactor Coolant Pump Supports - A490 Bolts"
Reference:
1)
LP&L Letter W3K82-0330 to NRC dated 6/8/82 2)
Telecon - R. G. Bennett (LP&L) to L. Martin (NRC) on 7/15/32
Dear Mr. Collins:
Evaluation of the significance of Potentially Reportable Incident No. 52 has been completed in accordance with 10CFR50.55(c) and is considered reportable. Hereafter, it will be referred to as significant Construction Deficiency No. 59.
If you have any questions, please advise.
Very truly yours, GDMcL/LLB/rd Attachment cc:
1)
Director Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 (with 15 copies of report) 2)
Director Office of Management Information and Program Control i
U. S. Nuclear Regulatory Commission hh Washington, D. C.
20555 i
W (with I copy of report) g i
da u
8207270466 820719 PDR ADOCK 05000382 s
PDR 1
.o FINAL REPORT SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 59
" REACTOR COOLANT PUMP SUPPORTS - A490 BOLTS" Introduction This report is submitted pursuant to 10CFR50.55(e) and describes a deficiency pertaining to the failure of A490 bolts during installation of the Reactor Coolant Pump Supports. The problem is considered reportable under the requirements of 10CFR50.55(e).
This problem has not been identified by LP&L to the Nuclear Regulatory Commission pursuant to 10CFR21.
Description of Deficiency This problem was identified to Ebasco by LP&L on August 1, 1980, as a result of an allegation submitted to the NRC by a NISCO employee. The problem as initially reported indicated that some A490 bolts had sheared during attempts to torque as prescribed by the AISC Specification.
Due to lack of documentativn by TiSc0 identifying the bolt shearing problem, it was difficult to determine the exact cause of the bolt failures.
In order to establish the actual mechanical properties of the installed A490 bolts, LP&L issued Purchase Order A-93022-D to Almay Research and Testing Corporation of Los Angeles, California, to perform testing and evaluation of the bolts.
Independent testing and evaluation was conducted by Ebasco Materials Applications and Design Engineering.
Based on these evaluations, it was determined that no problem existed with the mechanical properties or physical characteristics of the installed A490 bolts.
As a result of the evaluations and reinspections, it was determined that the initial installation was unacceptable.
Safety Evaluation The mechanical properties of the installed A490 bolts were evaluated by Ebasco Materials Application and Design Engineering and independently by Almay Research and Testing Corporation of Los Angeles, California.
Results of the analyses Indicated that the A490 material is acceptable for this application and that the problem resulted from improper installation.
Degradation of the Reactor Coolant Pump supports could result in the inability of the reactor coolant pumps to perform their required function during design loading conditions if the deficiency were not corrected.
Corrective Action Reverification program was established which required that all structural bolts in each support were properly torqued. The calibration of inspection wrenches was performed once each day during the inspection process.
A>>.
Each bolt that was inspected for proper torque was identified as accepted (bolt end painted green) or rejected (bolt end painted white). All bolts that were initially installed were impacted to 72 kips or 1150 foot-lbs.,
whichever occurred first, as directed by Ebasco Engineering.
Rejection was baued on the bolt breaking before reaching the desired torque value, or the nut continuing to rotate after a continuous impact of 10 seconds, or excessive bolt protrusion. A total of 195 bolts were replaced as a result of the reinspection program, none of which were a result of breakage.
All bolts identified as rejected were replaced with new A490 bolts.
The new bolts were from the same lot or heat number as the bolts used to establish the torque value for that particular period.
Based on the reinspection documentation reviewed, all bolts have been properly torqued with the exception of nine (9) bolts identified as inaccessible. These bolts were tightened two flats using a box end wrench and have been accepted by Ebasco Engineering.
Conclusion Based on the corrective action taken, it is concluded that the A490 bolts installed in the Reactor Coolant Pump Supports are adequate for their intended use.
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