ML13319A820
| ML13319A820 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 05/22/1991 |
| From: | Nandy F SOUTHERN CALIFORNIA EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9105300229 | |
| Download: ML13319A820 (5) | |
Text
Southern California Edison Company 23 PARKER STREET IRVINE, CALIFORNIA 92718 F. R. NANDY TELEPHONE MANAGER, NUCLEAR LICENSING May 22, 1991 714) 454-4504 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555 Gentlemen:
Subject:
Docket No. 50-206 Auxiliary Feedwater System Startup Testing Report San Onofre Nuclear Generating Station, Unit 1 This letter provides the results of the Auxiliary Feedwater System (AFW) tests conducted during startup from the Cycle 11 refueling outage. This testing confirmed the ability of the AFWS to meet all design criteria after the flow reduction modification approved by NRC Amendment No. 138, dated November 15, 1990. The flow reduction was required to minimize the probability of a water hammer by reducing the maximum flow to each steam generator to less than 150 gpm.
Amendment No. 138 requested these test results as a condition of approval for AFWS flow reduction. On September 10, 1990, we submitted the design requirements for the proposed flow venturis. The enclosure to this letter demonstrates the actual AFW flows meet the design requirements.
If you have any questions, please contact me.
Very truly yours, Enclosures cc:
G. Kalman, Senior NRC Project Manager, San Onofre Unit 1 J. 0. Bradfute, Project Manager, San Onofre Unit 1 J. B. Martin, Regional Administrator, NRC Region V C. Caldwell, NRC Senior Resident Inspector, San Onofre Units 1, 2, and 3 C. D. Townsend, NRC resident Inspector, San Onofre Unit 1 9105300229 910522 PDR ADOCK 05000206 IPDR
Enclosure Auxiliary Feedwater System Testing In the September 10, 1990 letter to the NRC, SCE transmitted the SONGS 1 Auxiliary Feedwater System Flow Requirements Calculation and the manufacturers data for the cavitating venturis to assist the NRC's review of our Amendment Application No. 185.
The calculation provided the technical support for the AFW system flow reduction and our justification for stating that the AFW system meets its design basis.
The physical venturi modification is complete and the system returned to service.
The return to service testing is also complete and Table 2.1, "AFW Requirements, Expected Flows and Margins," reflect the actual system performance.
The results of the AFW flow testing verify that the system is within the design basis.
The changes in system performance as a result of the return to service testing have been documented in a formal succeeding calculation.
Table 2-1 (Attached) presents the required flow requirements for each scenario and the margins expected.
The actual test results are identified by "**" in the table.
The remaining values are verified by calculation.
The Auxiliary Feedwater System consists of two independent and redundant trains.
Train A consists of motor-driven Auxiliary Feedwater pump G-10S and turbine-driven Auxiliary Feedwater pump G
- 10.
Train B consists of motor-driven Auxiliary Feedwater pump G loW.
TABLE 2.1 AFW REQUIREMENTS, EXPECTED FLOWS AND MARGINS Actual
/
Design Condition Required Flows Expected Flows Margin Remarks (GPM)
(GPM) 4.1 Loss of Normal Feed
>185 G10W=233 26%
To 3 S/Gs @1030 psia 4.2 MFW Line Break Upstream
>100 G10W=122 22%
To 2 S/Gs @ 1030 psia of Check Valve 4.3 MFW Line Break Down-
>175 G1OS=208 19%
To 2 S/Gs @ 15 psia Stream of Check Valve 4.4 Small.Break LOCA
>185 G1OW=233 26%
To 3 S/Gs @1030 psia 4.5 S/G Tube Rupture a)
>120 G1OW=294 145%
To 2 S/Gs @ 250-750 psia. GlOS cavitate
@319 gpm & 730 psig b)
>120 G1OS=250 108%
To 2 S/Gs @ 250-750 4.6 Normal Plant a)
>185 G1OW=272 47%
To 3 S/Gs @ 125-923 Cooldown psia b)
>185 G1OS=220 19%
To 3 S/Gs @
< 500 psig
- TABLE 2.1 AFW REQUIREMENTS, EXPECTED FLOWS AND MARGINS Actual /
Design Condition Required Flows Expected Flows Margin Remarks (GPM)
(GPM) 4.7 Steamline Break a)
>150 G1OW=233 55%
To 3 S/Gs @ 1030 psia outside containment b)
>280 G1OW=338 20%
To 3 S/Gs @ 700 psia c)
>280 G1OS=312**
11%
To 3 S/Gs @ 15-700 psia*
d)
>215 G1O+G1OS=383**
78%
To 3 S/Gs @ 875 psia.
Both pumps cavitated at 383 gpm.
e)
>215 G10W=288 34%
To 3 S/Gs @ 875 psia 4.8 Station Blackout a)
>185 G10=288 55%
To 3 S/Gs @ 923 psia b)
>185 G10W=272 47%
To 3 S/Gs @ 923 psia 4.9 ATWS
>185 G1OW=233 26%
To 3 S/Gs @ 1030 psia 4.10 Turbine Trip Loss a)
>185 G10W=272 47%
To 3 S/Gs @ 125-923 of Load, Loss of psia.
Vacuum Condenser b)
>185 G1OS=220 19%
To 3 S/Gs @ 125-923 psia*
4.11 Appendix 'R'
>185 G1OW=272 47%
To 3 S/Gs @ 923 psia <59 hours a) Venturis manually
>350 G1OW=450 28%
To 3 S/Gs @ 15 psia at 59 hours6.828704e-4 days <br />0.0164 hours <br />9.755291e-5 weeks <br />2.24495e-5 months <br /> bypassed
TABLE 2.1 AFW REQUIREMENTS, EXPECTED FLOWS AND MARGINS Actual **/
Design Condition Required Flows Expected Flows Margin Remarks (GPM)
(GPM) 4.12 Water Hammer
<450 G1O+G1OS
+G1OW=415 To 3 S/Gs @ 15-1030 4.13 Pump Runout
<420 G10S=312 To 3 S/Gs @ 15-1030 psia.
4.14 Steamline Break
<1419 G1OW=338**
To 3 S/Gs @ 15 psia Core Response 4.15 Steamline Break
<500 G10W=338**
To 3 S/Gs @ 15 psia Inside Containment
- Above 500 psig GlO is available.
- Shows the actual test data from the startup testing.
Note:
- 1. Where pressure ranges are shown the highest pressure was used to establish flow & margins.
- 2. Actual/Expected flows are from the most limiting conditions. Other pump combinations result in higher flows, increasing margins.