TXX-6047, Interim Deficiency Rept CP-85-34 Re Adequacy of Conduit Supports to Perform Intended Design Functions.Initially Reported on 850906.Field Verification Data Being Analyzed. Next Rept Expected by 870227
| ML20215K910 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 10/21/1986 |
| From: | Counsil W, Keeley G TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | Johnson E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| CP-85-34, TXX-6047, NUDOCS 8610280369 | |
| Download: ML20215K910 (2) | |
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OCT 22 '86 7:54 LICENSE TUGCO PAGE.02 Log # TXX-6047 File # 10110 l
903.9 TEXAS UTILITIES GENERATING COMPANY SKYWAY TowuA. ges 880ST,e OLivs sfas37. L2,54. DA11AAL TEXA9 78991 October 21, 1986 R 3@[@0\\V/ $'
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OCT 211986 Mr. Eric H. Johnson, Director j
Division of Reactor Safety and Projects U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76012
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SUBJECT:
COMANCHEPEAKSTEAMELECTRICSTATION(CPSES) 1 DOCKET NOS. 50-445 CONDUIT SUPPORT DESIGN SDAR: CP-85-34 (INTERIM REPORT)
Dear Mr. Johnson:
i on September 6,1985, we verbally notified your Mr. C. Gould of a deficiency involving the adequacy of conduit supports to perform their intended design functions. Our latest interim report, logged TXX-4805, was submitted on May 16, 1986. We are reporting this issue under the provisions of 10CFR50.55(e) and the required information follows.
DESCRIPTION The seismic conduits and conduit supports at CPSES, Unit 1, are segregsted into Trains A, B and C.
Conduit supports on Trains A and B are Seismic Category I. Train C conduit supports are non-seismic except for conduits larger than 2 inches in diameter and those supports which are Seismic Category II and either seismically designed or seismically restrained with aircraft cables. Non-seismic designed conduits are not within the scope of this issue.
Seismic conduit and support design is governed by design package S-0910 for Unit I and Common areas. This document describes various types of
" engineered" and " generic" supports and allowable conduit spans. Supports deviating from generic support criteria are identified as " Modified" or
" Individually Engineered" (IN) supports. These conduit supports were initially installed as field run systems supported in accordance with Gibbs &
Hill Drawing 2323-S-0910.
4 The S-0910 design package was generated in general conformance with industry practices. However, a number of potential design concerns related to conduit supports have been identified through external design review. These reviews resulted in several concerns regarding the adequacy of the conduit supports to perform design functions.
In orh r to resolve these issues a 100%
verification of the conduit system design is being conducted in accordance with CPRT Program Plan Item DSAP VIII.
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OCT 22 '86 7:54 LICENSE TUGCO PAGE.03 TXX-6047 October 21, 1986 Page 2 of 2 SAFETY IMPLICATIONS Failure of seismically designed conduits and conduit supports to meet the design criteria could result in an inability of associated safety-related systems to perform as required for safe operation and shutdown.
CORRECTIVE ACTION The identification and as-built configuration of conduit and conduit supports affected by the revised design criteria of S-0910 is currently being established through field verification. Demonstration of the adequacy of, or alternatively, identification of configurations requiting further study or modification is being accomplished through analysis of the field verification data.
Unistrut and transverse supports have been examined differently than in the above mentioned verification activity.
For Unistrut supports, a Unistrut Test Program was implemented to determine the adequacy of Unistrut supports with regard to torsional loading. Any Unistrut support determined from test to have capacities below those given in the original S-0910 package or not tested will be replaced or will be demonstrated to be not needed. All transverse supports will either be converted to multidirectional supports or will be demonstrated to be not needed.
Completion of these programs is currently scheduled for February 2,1986. We anticipate submitting our next report by February 27, 1987.
Very truly yours, W. G. Co is 1 By:
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G. S. Keeley Manager, Nuclear _u e/nsing JCH/amb c - NRC Region IV (0 + 1 copy)
Director, Inspection & Enforcement (15 copies)
U. S. Nuclear Regulatory Commission Washington, D.C.
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