ML20063N585

to Evaluation of Effects of Postulated Pipe Failures Outside Containment for McGuire Nuclear Station

ML20063N585
Person / Time
Site:	McGuire, Mcguire
Issue date:	10/01/1982
From:	DUKE POWER CO.
To:
Shared Package
ML20063N577	List: ML20063N576 ML20063N584 ML20063N585
References
MDS-PDG-77-1, NUDOCS 8210040279
Download: ML20063N585 (3)

Text

O EVALUATION OF THE EFFECTS OF POSTULATED PIPE FAILURES OUTSIDE CONTAINMENT FOR MCCUIRE NUCLEAR STATION May 2, 1977 h)

REPORT NO. MDS/PDG-77-1 Revision 1 8-15-77 Revision 2 10-06-73 Revision 3 11-05-80 Revision 4 1-26-81 Revision 1 2

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ffR DO O O PDR g K

f' f, 2) For purposes of evaluating the mechanical integrity

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v ef fects of the impact of a whipping pipe or jet on piping compone*ts (i.e., pumps, valves, flanges, etc.), piping component pressure boundaries are con-sidered to be pipe of the same size and wall thick-ness as the main process piping to which the compo-nents are attached. Bodies of valves (including check valves) are assumed not to f ail upon impact by a smaller whippf ng pipe or jet from a smaller pipe.

3) An active component is assumed to be incapable of per-forming its active function following impact by a whipping pipe or jet, unless pro., etherwise by detailed impact analysis. External valve operators are assumed to be incapable of performing their intended function following impact by a whipping pipe or jet.

4) Cables and electrical equipment imp.cted by pipe

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[ 's whip or jet impingement will be assumed to fail along 6

('%ss with the final actuated devices the cables and equip-j ment support. Only the consecuences of failure of these final devices (e.g., MOVs, transmitters, etc.)  !

will be considered in the Electrical analysis. Further- l j more, the failure mode will al ays - be nonnechanistically assumed to be the position associated with loss of power to the device.

5) If pipe supports are damaged by whipping pipes or jets, the target pipe supported by t he hangers is assumed to remain supported upon the loss of one hanger.

b) Environmental Interactions

1) Structures are assumed f ailed if their design pressure is exceeded, unless integrity can be demonstrated.

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2) The final actuated devices that cables and electrical

(s equipment support are assumed incapable of performing their function upon exceeding the environmental qualifica-6 tion parameters (temperature, pressure, relative humidity) of the cabling or electrical equipment.

c) An active component is assumed incapable of performing its active function upon experiencing environmental conditions exceeding the environmental qualifications of the active canponent.

4.2.2 Pipina Systems Enclosed Within Structures For the purpose of assuring compliance with the requirements of Section 4.1 for piping systems within enclosures, breaks are postulated in accordance with Section 3.2, and it is demonstrated by analysis that such enclosure is adequately

'~s designed to prevent damage to essential structures and

'"# equipment from the effects of pipe whip, Jet impingement, pressurization of the enclosure compartment, environmental conditions, and flooding associated with the escape of the contained fluid. Piping restraints within the enclosure may by accounted for in limiting the effects of the postulated pipe rupture.

4.2.3 Other High-Eneroy Pipina Systems For the purpose of assuring compliance with the requirements of Section 4.1 for piping systems neither physically separated i

from essential structures and equipment nor enclosed, breaks I are postulated in accordance with Section 3.2; and it is demon-l l strated by analysis that the effects of pipe whip, jet impinge-ment, compartment pressurization, environmental conditions, and N

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