ML19262A533
| ML19262A533 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 10/16/1972 |
| From: | Mallay J BABCOCK & WILCOX CO. |
| To: | Schwencer A US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML19262A532 | List: |
| References | |
| NUDOCS 7911130539 | |
| Download: ML19262A533 (1) | |
Text
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,,v o y P.O. Box 1260. Lyr.cncuri;, Va. 24505 Te.epnor.e: (703) 384-5111 October lo,1972 Mr. A. Schwen'.er Chief, ?'47 3 ranch h Directcrate of Licensing U.S. Atemic Energy Consission
'4ashingten, D. C.
205L5
Dear Mr. Schvencer:
In response to your informal request for information on the method of reactor coolant pump support, E&'d submits the folleving:
Ouring normal operation of all the 3&'417' fuel assembly plants, the reacter coolant pump and motor sets are part. ily supported by dead veight hangers. About one-half of the total weight of the pump and noter set is carried by these hangers, and the remainder is carried by the piping itself. The effect of this weight is included in the stress analysis of the piping, which meets the requirements of ANSI 331.7.
In addition to the dead weight supports, seismic snubbers are also attached to the pump-motor set as required to maintain the piping stresses below the specified levels. The need for seismic restraints, of course, varies with the individr.al site seismic criteria. The effects of the restraints were included in the piping seismic stress analyses and the requirements as to location, number, and size of snubbers specified to the Architect /Ingineer (who supplies them).
During initial installation of the reacter coolant pump motor, the dead weight hangers do not have to be employed. The reactor ecolant piping is sufficiently strong to carry the full weight of both pump and motor, in the absence of pressure and temperature in the 1 cop and provided both suction and discharge legs are already velded to the pu=p casing. ?cr these conditiens, the maximum stress in the piping occurs at the end of the L50 elbcv on the steam generator discharge piping (pump suctien). At that point, the primary bending stress is 18,500 psi compared to a material yield strengt:- of 3S,000 psi.
Very truly ycurc, EAECCCK & '4:LCCX CCX?ANY Nucley Power Generation Q
James T Mallay 22)y Xanager, Licensing M /db o539 s
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