TXX-6383, Interim Deficiency Rept CP-86-82 Re Cable Tray Hanger (Cth) Splice Welds.Initially Reported on 870106.CTHs Subjected to as-built Program W/Visual Exam or Ndt.Next Rept Will Be Submitted by 870717
| ML20206G288 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 04/03/1987 |
| From: | Counsil W, Keeley G TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| CP-86-82, TXX-6383, NUDOCS 8704140493 | |
| Download: ML20206G288 (2) | |
Text
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a Log # TXX-6383 9
File #10110 903.9 r
=
Ref: 10CFR50.55(e) nlELECTRIC April 3, 1987 Emurns Ske hesidens U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C.
20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET NOS. 50-445 AND 50-446 CABLE TRAY HANGER SPLICE WELDS SDAR: CP-86-82 (INTERIM REPORT)
Gentlemen:
On January 6,1987 we notified you by our letter logged TXX-6201 of a deficiency involving certain welds which are used to splice cable tray hangers (CTHs) channel sections end-to-end to form posts which we deemed reportable under the provisions of 10CFR50.55(e).
This is an interim report submitted to status corrective action implemented to date.
The CTHs of Unit I have been subjected to an as-built program. The CTHs without thermolag have been visually examined and the locations where this condition has occurred are noted on the as-built drawings.
Each condition will be " repaired" or " reworked" in accordance with established project procedures.
CTH's with potential hidden splice welds due to installed thermolag are being investigated as follows:
A)
To determine whether splice welds exist on the po',t and tier members of the CTH's, nondestructive testing (UT) is being utilized on members which are channels 62" or less in length (for C8 channels or larger, UT can be performed up to 84" or less length).
B)
Where the potential condition is identified by UT, the thermolag will be removed to provide for visual confirmation.
C)
Thermolag will also be removed from all supports where UT produces indeterminate results or cannot be utilized (e.g. CTH members over the lengths specified above) to verify the subject condition.
870414'0493 B70403 PDR ADOCK 05000445 g
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TXX-6383 April 3, 1987 Page 2 of 2 UT has been performed on over 1173 hangers to date which has identified 14 splice welds with this deficiency.
Each condition which is determined to be unacceptable by engineering evaluation will be " repaired" or " reworked" in accordance with established project procedures.
Some instances of the subject condition have been identified in Unit 2.
The cases identified to date have been corrected as part of the design verification program.
(Problems of inaccessibility due to thermolag installation are not of concern in Unit 2.)
Identification of the subject condition and any necessary corrective action will continue for Unit 2.
The cause of this construction deficiency is attributed to a lack of specific direction regarding problems encountered during the " original" fabrication and installation of the cable tray hangers.
The following Construction Procedures, which address cable tray and hanger installation for Units 1 and 2, have been revised to correct this condition.
-ECP-10, Rev. 9 (Unit 1)
Issued January 13, 1987 l
" Cable Tray Hanger Installation"
-ECP-10A, Rev. 4 (Unit 2)
Issued September 8, 1986
" Cable Tray Hanger Installation, Unit 2" l
We will submit our next report no later than July 17, 1987.
Very truly yours, bhr
&<d W. G. Co sil By: M, #
4/
G. S. Keeley
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Manager, Nuclear b ensing DAR/amb c - Mr. E. H. Johnson, Region IV Mr. D. L. Kelley, RI - Region IV Mr. H. S. Phillips, RI - Region IV i
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