TXX-4454, Significant Deficiency Rept SDAR-172 Re Drawing Requirements That No Tube Fittings Be Installed Between Two 45 Degree Bends in Instrumentation Tubing.Installations Will Be Reinspected & Tube Length Will Be Reduced to 8 Inches

Significant Deficiency Rept SDAR-172 Re Drawing Requirements That No Tube Fittings Be Installed Between Two 45 Degree Bends in Instrumentation Tubing.Installations Will Be Reinspected & Tube Length Will Be Reduced to 8 Inches

ML20115F782
Person / Time
Site:	Comanche Peak
Issue date:	04/10/1985
From:	Clements B TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	Hunter D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
SDAR-172, TXX-4454, NUDOCS 8504220025
Download: ML20115F782 (2)

Text

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D TEXAS UTILITIES GENERATING COMPANY MKYWAY TOWEN . 400 NORTH OLIVE MTHEET. L.R. MI . DALLAM. TEXAM 75201

m. "'.S I " d " E ! L . Apri1 10, 1985 TXX-4454

}[R @[2 0M[R APRI21985 Mr. D.R. Hunter, Chief p Reactor Project Branch 2 ,

U.S. Nuclear Regulatory Commission Office of Inspection & Enforcement 611 Ryan Plaza Drive, Suite 1000 Docket No.: 50-445 Arlington, TX 76012 COMANCHE PEAK STEAM ELECTRIC STATION INSTRUMENT FITTING LOCATIONS QA FILE: CP-85-11, SDAR-172 FILE NO.: 10110

Dear Mr. Hunter:

In accordance with 10CFR50.55(e), we are submitting the enclosed report of ,

actions taken to correct a deficiency regarding a drawing requirement that no tube fittings be installed between two 450 bends in instrumentation tubing.

Supporting documentation is available at the CPSES site for your Inspector's review.

Very truly yours, l ab BRC:tig Attachment cc: NRC Region IV - (0 + 1 copy)

Director, Inspection & Enforcement (15 copies)

U.S. Nuclear Regulatory Commission Washington, DC 20555 8504220025 850410 PDR ADOCK 05000445 S pop a[/ -

T1-9 7 a sursMsox or rexan e rst.ursen zu.ecrase co>n axr j t

TXX-4454 4/10/85 Page 2 ATTACHMENT INSTRUMENT FITTING LOCATIONS Description During a systematic review by TUGCo Nuclear Engineering to incorporate Component Modification Cards (CMC's) into the applicable drawing, a series of limiting conditions have been identified regarding the instrumentation tubing on CMC 57487.

Specifically, the design change contains a note regarding the location of fittings on tubing installations containing bend radii between supports.

The intent of the note was to state fittings were not allowed between supports in the event the length of tubing between the bend radii exceeds eleven inches (11"). However, the note has been interpreted incorrectly in the construction and inspection process to not allow fittings between the bend radii if the length of tubing (between the bend radii) is greater than eleven inches (11").

Misinterpretation of the note has resulted in instrumentation installations which may be unacceptable. The improper placement of fittings could amplify stress intensity factors beyond the current seismic evaluation. As a result, associated instrumentation and control systems could be rendered inoperable due to failure of the tubing and supports during a seismic event. The deficiency has been dc:umented on a site nonconformance report.

Safety Implications In the event the deficiency had remained undetected, the capacity of the operator to safely monitor plant conditions could be adversely affected during a seismic event.

Corrective Action Using the instrument seisnic support drawings, engineering will identify the specific installations for which specific as-built information will be required for evaluation. These installations (approximately 100) will be re-inspected by site quality personnel. For the purposes of identification and inspection, the tubing length requirement between bend radii will be

. reduced to eight inches (8").

L Based upcn the results of the inspection, individual installations will be evaluated on a case-by-case basis. Rework, if required, will be specified and implemented. The subject note has been clarified to preclude further l

recurrence.

In order to validate the identification and inspection process, engineering personnel will perform a field verification of an additional 100 installations.

The sample will be expanded as required.

i Our current schedule indicates engineering and QC activities should be complete in mid-May. Construction activities will be dependent upon release of systems by operations.

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