ML20031A969
| ML20031A969 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 09/16/1981 |
| 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, W3K81-0338, NUDOCS 8109280438 | |
| Download: ML20031A969 (3) | |
Text
_ _ _ _ _ _ _ _ _ _
DH4 so.ssw)$1G3Gy r.
.7M I
l OUIStANA 342 OcLAnONOe natu P O W E F1 & L I G H T P O 80x 6008
- NEW OnLEANS LOUISIANA 70174 * (504) 366 2345 UTE NI[sS$
D L ASWELL S ept cnber 16, 1981 Vce Presdent Power Producten W3K81-0338 Q-3-A35.07 Q-3-A?. 02.01 gg Mr. K. V. Seyfrit, Director, Region IV y gj',@
U. S. Nuclear Regulatory Commission bl Office of Inspection and Enforcement 611 Ryan Plaza Drive, Suite 1000 gg ggg jz{GlOM lV Arlington, Texas 76012 Subj ect: Waterford SES Unit No. 3 Docket No. 50-382 Interim Report of Potentially Reportable Incident No. 52
" Reactor Coolant Pump Supports - A490 Bolts"
Reference:
Telecon - L. L. Bass (LP&L) to B. Hobacek (NRC) on August 18, 1981
Dear Mr. Seyfrit:
In accordance with the requirements of 10CFR50.55(e), we are hereby providing two copies of the Interim Report of Potentially Reportable Incident No. 52, " Reactor Coolant Pump Supports - A490 Bolts."
If you have any questions, please advise.
[ \\b I jf^b t
Very truly yours,
, n i-e-
+r s y XL,AL*jn N ' r(() Q D. L. Aswell O EP y ~
I--
a.
1981r
~0 DLA/LLB/grf
% ly'greer 5
/4\\
Attachment
).
g
'161fl
/
cc: 1) Director g
7 Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission S
Washington, D. C. 20555 (with 15 copies of report)
/I
- 2) Director Office of Management Information and Program Control U. S. Nuclear Regulatory Commisr,lon Washington, D. C. 20555 (with 1 copy of report) 8109280438 810916
{DRADOCK 05000362 PDR
INTERIM REPORT POTENTIALLY REPORTABLE INCIDENT NO. 52
" 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. At this time the reportability of this problem has not been determined. To the best of our knowledge, this problem has not been identified to the Nuclear Regulatory Commission pursuant to 10CFR21.
DESCRIPTION OF PROBLEM 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.
At first, it was believed that the problem was caused due to incorrect reuse of the A490 bolts by NISCO craf t during installation. However, subsequent testing at LI, Waterford Site by Ebasco Construction Engineering and LP&L QA showed questionable results similar to those encountered during the initial installation.
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. The results of this testing are documented on Almay Report No.
C-14330 dated February 12, 1981.
Independent testing and evaluation was conducted by Ebasco Materials Applications and Design Engineering.
In addition, Ebasco Design Engineering reviewed and commented on the Almay report.
Recommendations by Ebasco New York Design Engineering are documented on Memorandum No. 8-B-2 dated July 22, 1981.
N1SCO was directed by Ebasco to reinspect (two bolts per connection) the bolts installed in the Reactor Coolant Pump Supports.
This reinspection revealed several problems with NISCO's installation of these bolts. These problems were inadequately torqued bolts and bolts that were the wrong length for the structure. A further problem that surfaced was the fact that N1SCO had performed the bolt inspection in most cases several months af ter the bolts were installed and the inspection torque values varied considerably. Following this, Ebasco directed NISCO to perform a 100% retorque of the bolts to a value o f 1000 f t.
lbs.
Approximately 1400 bolts of Ae90 naterial are presently installed in the four Reactor Coolant Pump Supports.
Results of the analysis conductej thus far indicate that the A490 material supplied is acceptable for this application and that the problem is improper installation.
l
I a e -
LP&L and Ebasco are continuing the evaluation of this problem and have outlined a verification program.
SAFETY EVALUATION This aspect will be addressed in the final report.
CORRECTIVE ACTION Corrective action taken up to this time includes a 100% retorquing of the bolts in the Reactor Coolant Pump Supports and an inspection program to identify the bolts that are the wrong length for the structure.
Based on the results of these actions, an additional torque verification will be performed.
The corrective action to be taken to verify the acceptability of the bolting of the Reactor Coolant Pump Support structures is outlined in the following procedure:
a) Calibrate the torque wrench by using six (6) bolts in the bolt tension calibrator. Record the air pressure required to obtain this torque, the number of turns of the nut, aan the tension on the bol'.
b) Set the air pressure regulator to the minimum pressure requirad to reach 1150 ft. Ib. torque.
c) Tighten twenty (20) bolts installed in the Reactor Coolant Pump structure with tne above calibrated equipment to within torque range of 1125 - 1150 ft.
Ibs.
If more than five (5) cf the initial 20 belts inspected fail, the work is to be stopped and the program reevaluated, d) Testing shall continue until all bolts in the reactor coolant pump supports are torqued. If at any time, 25% of the torqued bolts are found to be defective, the work is to be stopped and the program reevaluated.
It is further noted that all A490 bolts procured for future use will be controllcd from procurement to final installation. Construction and Quality Control procedures have been revised to provide direction on how to assure proper requisitioning, warehousing, installation, and Q.C verification of A490 bolts on this project. Program requirements now mandate that bolts used in the bolt tension calibrator will be of the same lot or heat as those used in the installation. This is to eliminate any further confusion between those bolts used in the tension calibrator and bolts used for actual installation.
Corrective action will be completed and a Final Report submitted on or before December 31, 1981.
_g