ML19246A392
| ML19246A392 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 06/13/1979 |
| From: | Taylor J BABCOCK & WILCOX CO. |
| To: | Mattson R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7906190452 | |
| Download: ML19246A392 (6) | |
Text
.
B'abcock & Wilcox g,e, aere,eoc, 0,m P.O Sex 1260. Lynchturg Va. 245C5 Te'ecncne: ;SO4) 384 5111 June 13, 1979 Dr.
R. J.
Mattson Director, Division of Systems Safety Office of Nuclear Reactor Regulation U.
S. Nuclear Regulatory Commission
.ia s h in g t o n, D.C.
20555
Subject:
Commitments Resulting from the T'!I-2 Incident Gentlemen:
Attached is an update o f the commitments to the NRC, made by Babcock 5 Wilcox on behalf of our operating plant customers.
This is a total list of the commitments completed and outstanding as I now see them.
Note tha since my letter to vou of April 30, 1979, many contaitments have been completed, some have been added, a few have beer dropped, and some schedules have been revised; all this has been our attempt to satisfy both our customers and the staff as the required work has become more well defined.
If you have any questions, please call me (Ext. 2817).
Very truly yours, SL *, /
James H. Tavlor
['
Manager, Licensing Nuclear Power Generation Division JHT:nw Attachment cc:
Mr.
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References 1)
J. H. Taylor to R. J. Mattson,'30 April 79,
" Babcock & Wilcox Company Commitments".
2)
" Evaluation of Transient Behavior and Small Reactor Coolant System Breaks in the 177 Fuel Assembly Plant" 7 May 79.
3)
J. H. Taylor to R.
J. Mattson, letter of 13 May 79 transmitting " Report on Analysis Methods for RCS Natural Circulation".
4)
J. H. Taylor to Harold Denton, " Independent Auxiliary Feedwater Control System", 22 May 79.
5)
J.
H. Taylor to D.
F. Rcss, Jr., " Response to Thermal Shock Con;ern", June 13, 1979.
Q30
Analytical Commitments from Reference 1 Commitment Status I.A Perform calculations, wors t
. Completed in Section 6.2.1 case break without AFW for of Ref.
2.
30 minutes.
NOTE:
Operator action was required in 20 minutes to avoid core damage.
I.3 Document natural circulation Completed in Appendix 1 tests conducted at Davis-to Ref.
2.
Besse and Oconee.
I.C Document all occurrences of Completed in Appendix 1 natural circulation which to Ref.
2.
happened inadvertently, include a description o f unexpected behavior.
I.D Document natural circulation Completed in Ref.
3.
analytical methods.
I.E Summarize and document Due 6 July 79.
sensitivity in key parameters 35W believes that much of the identified in the Tedesco work implied by NUREG-0560 report.
has already been submitted.
No further submittals are planned aside from those listed in this status report.
I.F (Deleted)
I.G Define and document thermal Completed in Ref.
5.
shock criteria for operation of low temperature with HPI pumps running and no natural circulation.
I.H Assessment of the safety Completed in Appendix 5 concerns raised in the report o f Re f.
2.
of Dr. Michelson.
II.A CRAFT Analyses 1.
Stuck open PORV, RCPs on, Deleted:
iten d2 below bounds normal AFW, 2 HPI pumps this case and shows acceptable results.
2.
Stuck open PORV, RCPs on, Completed in Section 6.2.3.1, normal AFW, 1 HPI pump.
Case 1 of Ref.
2.
Commitment Status 3.
Stuck open PORV, RCPs on, Deleted:
This case closely normal AFW, 200 gpn HPI.
parallels item 44 below and results in core damage.
4.
Best estimate of TMI-2 Completed in Section 3.3 transient.
of Ref.
2.
5.
.07/.02/.01 ft breaks.
Completed in Section 6.2.1 of Ref.
2.
6.
LOOP and LCMFh, no RCPs, Completed in Section 6.2.2 no AFW, manual HPI at of Ref.
2.
20 minutes.
7.
1.05 in break in the Completed in Section 6.2.3.1, pressuriner steam Case 2 of Ref.
2.
space S.
References to completed Clarification is requested of small break LOCA analyses the staff on this item.
and models.
II.B CADDS Analyses 1.
TMI-2 incident benchmark Completed in Section 3.2 of Ref.
2.
2.
AFW delay study - best Completed in Section 4.3 estimate.
of Ref.
2.
3.
Reactor trip with LOMF -
Completed in Section 4.4 best estimate.
of Ref.
2.
4.
Studies supporting changing Completed in Section 4.2 PORV and reactor trip of Ref.
2.
setpoints - best estimate.
5.
Sensitivity to initial Deleted.
power level.
III.A Deleted -- This was a repeat o f Section II above.
III.B Details of B5W's evaluation Completed in A andix 5 of the 'fichelson report.
of Ref.
2.
III.C System response to total Original submittal date -
loss of heat sink.
25 May 79 Revised submittal date -
31 Julv 79 III.D Sensitivity study of system Original ' submittal da to -
25 May 79 k
response to AEW flow rate.
Revisedsubmitt21b}Cate -
6 July 79 Commitment Status III.E Et.ect of anticipatory trip Completed in Section 4.4 on LOMFW.
,of Ref.
2.
IV A.
Benchmark analysis of Due 15 June 79.
sequential AFW to OT5G's for LCMFN.
Il B. System response to PORV and Completed in Section 6.2.3.2.3 Code safety valve actuation.
of Ref.
2.
Benchmarking natural circu-Due 2 July 79.
IV.
c.
lation cocling in CRAFTII.
IV D.
Evaluation of Michelson report Completed in Appendices 4 and operating criteria for and 5 of Ref.
2.
small breaks.
IV E. Worst _ase small break with Completed in Ref.
2.
1, Section 6.0, failure.
Supplement 1.
V.
Reliability analysis of Due 2: June 79.
the ICS.
VI.
A.
Operating instructions for Completed in Appendix 4 management of small breaks.
of Ref.
2.
VI.
B.
ICS FMEA Included in Item V above.
Non-Analytical Commitments from Ref. 1 I.
Develop means for decoupling Completed:
As cc mmitted in AFW control from the ICS.
Ret.
4, sfstem dc criptions were sent to our customers on 8 June ~9.
II.
A. More positive PORV Several possible methods were indication.
sent out fo r custome r review ;
terts are scheduled for week of 11 June 79 at the Alliance Research Center.
II.
3.
Saturated condition indicator Completed:
Proposals for computer for the RCS.
alarms have been sent to customers.
Proposals for computer-independent meters will be sent sor
\\'
Commitments Made at the 1 May 79 Meeting in Lynchburg Commitment Status 1.
CRAFT analysis for.01 ft Completed in Section 6.2.4.3.1 break to determine if Michelson
'of Ref.
2.
phenomenon is a problem for 17~ FA plants.
2.
Small break calculation to show Completed in Section 6.2.4.3.3 HPI provides adequate cooling and Vol.
3, Section 6, of at 2500 psig (Burp 5 Slurp)
Ref.
2.
3.
CRAFT analysis for.01 ft Completed in Section 6.2.4.3.2 break with AFh to only one of Ref.
2.
OTSG.
4 Check capability of RC pumps Completed in Appendix 3 to restart in two-phase flow, of Ref.
2.
5.
Discussions on CRAFT steam Completed in Section 5 of space break analyses.
Ref.
2.
6.
CRAFT analysis for.01 ft-Completed in Volume 3, break with AFN to only one Section 6 of Ref.
2.
OTSG for raised-loop plant.
7 Document CRAFT analyses Completed in Section 6.2.1 previously done for Duke of Ref, 2.
Power Company Other Commitments 1.
Davis-Besse 1 analysis Completed.
Transmitted to supporting PORV setpoint the customer on 10 May 79.
=
2365 psig, safety valve setpoint 2435 psig.
=
2.
OTSG thermal stress evaluation Completed in Appendix 2 of (no RCS flow, steam inside Ref.
2.
3.
Evaluat2 the pressurizer safety Completed in Section 6.2.3.2.3 valve break.
of Ref.
2.
4.
Probability study for opening Original submittal date -
the PORV 25 May ~9 Revised submittal date -
6 July 79 230 130
.