ML18033B089
| ML18033B089 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 12/19/1989 |
| From: | Black S Office of Nuclear Reactor Regulation |
| To: | Kingsley O TENNESSEE VALLEY AUTHORITY |
| References | |
| TAC-62260, NUDOCS 8912210075 | |
| Download: ML18033B089 (6) | |
Text
December 19, 1989
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d<Q Docket No. 50-260 Mr. Oliver D. Kingsley, Jr.
Senior Vice President, Nuclear Power Tennessee Valley Authority 6N 38A Lookout Place 1101 Market Street Chattanooga, Tennessee 37402-2801
Dear Mr. Kingsley:
Distribution NRC PDR Local PDR ADSP Reading DCrutchfield BDLiaw RPierson SBlack quay BWilson WSLittle ACRS(10)
GPA/CA LA GGears DMoran JRutberg BGrimes EJordan DTerao SKim
SUBJECT:
BROWNS FERRY NUCLEAR PERFORMANCE PLAN - SECTION III.13.3 - FLEXIBLE CONDUIT - REqUEST FOR ADDITIONAL INFORMATION (TAC 62260)
As part of our review of the Browns Ferry flexible conduit program (Nuclear Performance Plan,Section III.13.3, Volume 3 and TVA letter dated August 18, 1989), the staff finds that additional information is needed to complete its review.
We request that you provide us with responses to the attached request for additional information within 60 days of the receipt of this letter.
The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents; therefore, OMB clearance is not required under P. L.96-511.
If you have any questions concerning this request, please call the Browns Ferry Project Manager, Gerald E. Gears, at 301-492-0767.
Sincerely, Original signed by Gerald E. Gears for Suzanne Black, Assistant Director for Projects TVA Projects Division Office of Nuclear Reactor Regulation
Enclosure:
Request for Additional Information cc w/enclosure:
See next page 85'12210075 891219 PDR ADOCK 05000260 P
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'Mr. Oliver D. Kingsley, Jr.
CC:
General Counsel Tennessee Valley Authority 400 West Summit Hill Drive ET llB 33H Knoxvi.l 1 e, Tennessee 37902 Mr. F. L. Moreadith Vice President, Nuclear Engineering Tennessee Valley Authority 400 West Summit Hill Drive WT 12A 12A Knoxvi1 le, Tennessee 37902 Dr. Mark 0. Medford Vice President and Nuclear Technical Director Tennessee Valley Authority 6N 38A Lookout Place Chattanooga, Tennessee 37402-2801
- Manager, Nuclear Licensing and Regulatory Affairs Tennessee Valley Authority 5N 157B Lookout Place Chattanooga, Tennessee 37402-2801 Mr. 0. J. Zeringue Site Director Browns Ferry Nuclear Plant Tennessee Valley Authority P. 0.
Box 2000
- Decatur, Alabama 35602 Mr. P. Carier Site Licensing Manager Browns Ferry Nuclear Plant Tennessee Valley Authority P. 0.
Box 2000
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- Decatur, Alabama 35602 Mr. G. Campbell Plant Manager Browns Ferry Nuclear Plant Tennessee Valley Authority P. 0.
Box 2000
- Decatur, Alabama 35602
- Chairman, Limestone County Commission P. 0.
Box 188
- Athens, Alabama 35611 Claude Earl Fox, M.D.
State Health Officer State Department of Public Health State Office Building Montgomery, Alabama 36130 Regional Administrator, Region II U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W.
Atlanta, Georgia 30323 Mr. Danny Carpenter Senior Resident Inspector Browns Ferry Nuclear Plant U.S. Nuclear Regulatory Coranission Route 12, Box 637
- Athens, Alabama 35611 Dt. Henry Myers, Science Advisor Coomittee on Interior and Insular Affairs U.S.
House of Representatives Washington, D.C.
20515 Tennessee Valley Authority Rockville Office 11921 Rockvil le Pike Suite 402 Rockville, Maryland 20852
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ENCLOSURE RE UEST FOR AODITIONAL INFORMATION ON BRO T 2 The inspection criteria for the Browns Ferry flexible conduit program are provided in TVA's program plan" (Reference 1).
The bases for the criteria are discussed in TVA calculation CEB-MA2-006 (Reference 2).
As a result of our review of the criteria and their bases, the staff requires additional informa-tion to complete its review:
2.
3.
The definition of K as well as associated numerical values do not reflect the intent of the CEB-MA2-006 calculation.
In the calculation, all equip-ment and devices are subject to thermal movement which is correct.
How-ever, the definition in your Program Plan seems to indicate otherwise.
Please clarify the discrepancy.
In obtain'ing resultant earthquake-induced displacement at the top of the Motor Control Center (MCC), the shaker table displacement is subtracted from the accelerometer derived displacement.
The licensee had indicated that it agrees with the staff that the subtraction of the displacement is not correct.
Subsequently, the licensee proposed to use the phase rela-tionship of the two motions to sum displacements algebrically.
The staff believes that the algebraic phase sum is not valid.
An absolute sum of the two maximum displacements is more appropriate and conservative.
Alge-braic sum is not reliable because peak displacement of the equipment represents a displacement at resonance frequency.
This displacement is obtained by applying a harmonic motion to the shaker table with the equip-ment's natural frequency.
Any algebraic calculation at resonance is not valid beca'use of the relatively large displacement associated with resonance.
This violates Hadamard's principles (Reference 4), which states that, among other things, one should not rely on a calculation where a small change in an introduced parameter represents a large change in the result.
Please provide justification for using a algebraic sum of the displacements for these calculations.
Please provide the references for the sources of the maximum shaker table acceleration of 1.4g and the displacement 0.137 inches and compare their significance -to the FSAR (plant specific floor response spectra).
Accelerometers are assumed to be located at mid-point of the cabinet.
Please provide verification and documentation for this assumption.
Once displacement of the mid-point is assumed, it is multiplied by two to extra-polate the data to the top of the cabinet where the flexible conduit is attached.
This is not a conservative, extrapolation since the bottom of the equipment is anchored to the floor and the top is free thus acting as a cantilever.
Free end displacement of the cantilever is more than twice the mid-point displacement.
5.
6.
TVA is currently updating piping calculations under the Browns Ferry's IAE Bulletin 79-14/79-0 programs.
This may affect results obtained in CEB-MA2-006 upon which flexible conduit inspection criteria are bases.
Please discuss Tennessee Valley Authority's (TVA) plan for possible future revision of the criteria.
In Reference 3 thermal expansion and dynamic displacement of the main steam pipe are tabulated.
However, there is no indication that dynamic displacement includes the seismic response of the pipe.
Please discuss how the value'of the dynamic displacement was deve1oped and the load combinations considered.
7.
8.
9 ~
10.
12.
In Reference 3, Appendix 8, a response spectrum is presented.
Please discuss how this pertains to the main text of the report (Reference 1).
TVA analysis considered only displacement of the equipment, devices and pipes.
These represent only one end of the flexible conduits.
The other end of the flexible conduit is supported most likely by a rigid conduit.
Rigid conduit also is subjected to seismic/thermal movements.
Please discuss why the final length of the flexible conduit does not consider displacements in both ends of the conduit.
In considering'CC thermal
- movement, a four foot length of the cabinet is used.
Please provide the basis for assuming a four foot length.
Terminals of the flexible conduits will be subjected to an inertia load from a seismic motion.
Please discuss how this load is accounted for in the seismic qualification of the end connections.
It was stated in the program plan that approximately 500 flexible conduits.
have been identified which require inspection.
Please provide a discus-sion on how this number demonstrates that all the flexible conduits are accounted for.
For instant, it is not certain that flexible conduits between two buildings are considered.
If they are considered, the con-duits between the buildings should be included in the inspection criteria.
If not, one should provide a justification not considering them.
On Page 5 of the Reference 2 calculation, the exponent -6 is missing at two locations.
Please verify that the omission is an editorial error.
REFERENCES 2.
3.
Tennessee Valley Authority, August 18, 1989 letter from M. Ray to
- NRC, forwarded the "Browns Ferry Flexible Conduit Program Plan."
CEB-MA2-006 "Seismic/Thermal Movement Class IE Flexible Conduit" Revision I, dated July 14, 1989.
EN DES Calculations "Seismic/Mechanical Analysis of Metal Bellows-Instrument Flex Hose "No.
CEB 82-0913-023, Revision 0, dated September 13, 1982.
4.
Issacson and Keller, "Analysis of Numerical Methods," John Wiley 5 Sons Inc.,
New York, 1966.
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