ML081120510

Summary of March 20, 2008, Meeting with Tennessee Valley Authority Regarding Steam Dryer Portion of the Extended Power Uprate Review (TAC Nos. MD5262, MD5263, and MD5264) - Slides

ML081120510
Person / Time
Site:	Browns Ferry
Issue date:	03/20/2008
From:	Tennessee Valley Authority
To:	Office of Nuclear Reactor Regulation
Brown Eva, NRR/DORL, 415-2315
References
TAC MD5262, TAC MD5263, TAC MD5264
Download: ML081120510 (7)

Text

TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT Extended Power Uprate Steam Dryers March 20, 2008

Steam Dryer Analyses AH-ft

• Unit 1 Analysis

- Submitted March 6, 2008

- Includes:

o Unit 1 specific strain gage data o Latest bias and uncertainty o FEM corrections o Noise reduction

- Results Location Node SR-P SR-a Freq. Shift (%)

.1 opCoerInerHo"~r co Oerta17pro,Perf.P ,ate ~ fý88059-. 30

2. Top Cover/Tie Bar Base 107054 3.47 1.59 10

3. Top Cover/Tie Bar Base 102407 3.29 1.62 2.5

4. Top Cover Middle Hood/Top Perf. Plate/Top Cover Overlap 91420 3.05 1.63 10

5. Top Cover/Tie Bar Base 96561 3.96 1.94 10

6. Top Perf/Top Cover/Dam Plate 103088 4.31 1.98 7.5

7. Submerged Drain Channel/Skirt 104539 2.57 2.15 10

8. Dam Plate/Lock 102521 4.76 2.19 7.5

9. Top Cover Inner Hood/Hood Support/Tie Bar Base 103094 4 2.28 10

10. Top Perf/Top Cover/Dam Plate 103089 5.14 2.4 5 2

Steam Dryer Analyses Unit 2 Analysis

- Scheduled to be submitted March 31, 2008

- Will include:

o Latest bias and uncertainty o FEM corrections

" Noise reduction 3

Steam Dryer Analyses Unit 3 Analysis

- Scheduled to be submitted June 2008

- Will include:

o Unit 3 specific strain gage data o Latest bias and uncertainty o FEM corrections o Noise reduction

- Outage status o Outage began March 18 o Acoustic vibration suppressors will be installed 0Strain gage data will be obtained following restart 4

Steam Dryer Analyses Potential for SRV Resonance

- Frequency range 105 Hz to 112 Hz most likely

- No demonstrated SRV resonance at CLTP velocities from plant data

- 1/5 Scale testing of A & B main steam lines o Testing shows SRV frequency onset starting at CLTP and small increase at EPU Mach numbers

- 1/8 Scale testing for EPU prediction o In progress

" Used to determine need for mitigation modifications 5

RAI Status

• Group 1 -January 31,2008

- Generic questions, plans to use unit-specific data, clarifications

• Group 2 - March 6, 2008

- Unit 1 stress analysis, damping

• Group 3- March 31, 2008

-Unit 2 stress analysis, misc.

• Group 4 -June 15, 2008

- Unit 3 stress analysis 6

Steam Dryer Monitoring Plan

" Draft provided for discussion

• Modeled after Vermont Yankee

• Includes

- Test plateaus at 5%

- Power increments of 2.5%

- Performance criteria based on limit curves

- Proposed license conditions 7