W3P82-1755, Forwards Model Testing of Safety Injection Sys Sump. Grating Cages Will Be Installed to Protect Intakes from Vortex Formation
| ML20054J897 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 06/28/1982 |
| From: | Maurin L LOUISIANA POWER & LIGHT CO. |
| To: | Tedesco R Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20054J898 | List: |
| References | |
| Q-3-E24, W3P82-1755, NUDOCS 8206300179 | |
| Download: ML20054J897 (2) | |
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LOUISIANA P O W E R & L I G I1 T[ P O BOX 6008 14aOuanOsOn1nur
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unurn srsrf M June 28, 1982 t, y, g3ygig Vice President Nuclear Operations W3P82-1755 Q-3-E24 B.06 Mr. R. L. Tedesco Assistant Director of Licensing Office of Nuclear Reactor Regulations U.S. Nuclear Regular ry Commission Washington, D.C.
20555 SUB.J ECT : Waterford 3 SES Docket No. 50-382 Transmittal of Model Testing of the bufety Injection System Sump Report
Dear Mr. Tedesco:
Enclosed is a copy of the report by Western Canada Hydraulic Laboratories, Ltd. on the !!odel Testing of the Safety Injection System Sump for your review. The purpose of the hydraulic model study was to test and modify, if necessary, the Safety Injection System (SIS) sump to demonstrate that the Waterford 3 sump design will permit operation of the Safety Injection System and Containment Spray System (CSS) without vortex formation.
In addition the head loss across the screen cage at each intake was measured for use in the Net Positive Suction Head calculation.
In order to accurately determine vortex formation and head losses a 1:1 scale model was constructed of the SIS sump, intakes, screen cage and all containment geometry which could significantly affect the approach flow conditions. To investigate the susceptibility of the Wsterford 3 intakes to vortexin;, the vertical and horizontal screens were extensively blocked to create sump flow conditions which are much worse with respect to vortex-ing than.iny expected in the plant. When the recommended grating cages encapsulacing the intakes were installed, no vortices developed under any flow conditions tested. The conclusions and recommendations arrived at as a result of the testing are as follows:
1)
The sump and intakes with grating cages will not develop vortices even with 90 percent of the screen cage's open g
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area blocked and single intake discharges up to 11,000
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US gpm.
8206300179 820628 PDR ADOCK 05000382 A
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I' Mr. R. L. Tedesco W3P82-1755 i
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- 2) The maximum measured intake head loss referred to a prototype discharge of 8640 US gpm and with 50 percent screen blockage was 0.905 ft. for the train A intake and 0.892 ft. for the train B intake.
- 3) The maximum measured screen loss referred to a prototype discharge of 11,780 US gpm and with 50 percent screen blockage was 0.098 ft.
- 4) Based on the test results, it was recommended that the i
intakes be protected from vortex formation by installation of grating cages as shown in Figure 14 of the report.
In accordance with our response to Question 211.91 the recommended grating 4
cages will be installed at Waterford 3.
We feel that this report along with the actual NPSH, which will be provided after the completion of ECCS preoperational testing, will demonstrate that i
the SIS sump design will perform adequately with no vortex formation and minimal head losses and that the NPSH at the pumps will be adequate for proper operation of the SIS and CSS in the event that they are required.
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Yours very truly,
/7 M G w L. V. Maurin LVM/REW/pco Attachment cc w/ attachment :
S. Black, C. Liang cc w/o attachment:
E. L. Blake, W. M. Stevenson i
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