ML19312C767
| ML19312C767 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 06/20/1967 |
| From: | Grimes B US ATOMIC ENERGY COMMISSION (AEC) |
| To: | Boyd R US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 7912190980 | |
| Download: ML19312C767 (2) | |
Text
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6 g 10 Roger S. Boyd, Assistant Director for Reactor Projects, DRL DT Charles G. Long, Chief, RPB #3, DRL g S4"*d THRU:
B. Grimes, Reactor Project Branch No. &d@d,gG.
Division of Reactor Liesnsing Ch DUKE POWER COMPAllT - DOCKET NOS. 59269,50-2)),AND50-287
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OnJune6,1967,MrLeeof$ukePeserCompanycalledtoprovideinformation f
on topics raised at the May 31, 1967, ACES Subcommittee meeting ar.d by the staff in recent telephone conversations. The following topics were discussed:
(1) Thermal Design - Mr. Lee indicated that Duke and B&W were willing to list thermal design as a research and development item and would so state in the direct testimony to be given in the hearing and also in an amendment if the staff requires this.
I see no reason why this must be documented before the hearing since some areas of the thermal hydraulic design are already indicated as R&D.
(2) Rod Drives (a)
In response to the subcommittee's concern, B&W proposes to install a clutch which will provide positive insertion of the drives after a scram signal has been received.
They will also provide a device to prevent blowdown forces from lifting the rods after a scram.
(This latter provis-ion was installed after calculations indicated that upward forces during blowdown would be about equal to the weight of the rod.)
(b)
If a seal is completely lost on the rod housing, a ecllar on the shaf t will cut off flow out the break. Break of a vent line will cause no rod motion. Loss of the buffer aes' housing would cause a slow outward movement of the rod. Loss of the bolts on top of the housing would casse rod ejection.
(3) Turbine Stop Valves - In case of a steam line break accident, both valves on the unbroken line most close to prevent blowdown of the second generator. The valves on the broken line could not take the accident pressure in the reverse direction.
OFTICE >
SURNAME >
DATE >
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Form AEC.318 (Rev.FM) u.s. GOVEltMMENT PmM fM CmCI d M214-43 7912190980
JUN 2 01967 Roger S. Boyd (4) Bnergency Feedwater Pumps - Contrary to previous indications
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the applicant states that two emergency feedwater pumps will not be installed witn the first unit. We had requested that redundancy of energency feedwater pumps provided and Duke pro-posed that the outlet of the pumps fer each unit be cross-connected. This is a satisfactory solution when more than one unit is in operation but does not solve the requirement for redundancy when only cne unit is in operation. The applicant had agreed to look into installing the Unit 2 feedwater pump with Unit 1 and running temporary steam piping but now states that this will not be done.
(5) Refueling Meinistrative Error - If a high enrichment assembly werc placed in a low enrichmene region of the core burnout could take place according to Duke.
(6)
Steam Line Break - Duke indicated that the reactivity balance for the steam line break coincident with multiple tube rupture
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was calculated using all three high pressure injection pumps.
For the 125 tube rupture case with one rod stuck out of the l
core, the minimum shutdown margin calculated was 1.4%.
If only one boron injecticn pump operated this margin would be 1.2%.
The core is not uncovered in the 125 tube rupture case (which corresponds to a 0.2 ft2 andcoreuncoverywouldnotoccurfora0.4ft{imarysystem) break in the p break.
(7)
Instrumentation - At our requese the servo channel will be i
connected to one rather all 4 of the flux hhannels and a 2 out of 4 safety system will be used. Lee said that isolation amplifiers might be proposed as sufficient at a later date on the basis of equipment tests.
(8) Containment - We expressed our disapproval of tack welding the reinforcing bar to provide cathodic protection since over-heating and resultant embrittlement of the bar could occur in the absence of rigid quality controls. Duke stated that either the quality controls would be delineated or tack welding elimi-nation of tack welding would be possible if soil resistivity tests this week show high enough resistivity to eitminate need for a cathodic protection system.
Distribution:
Suppl. (3X 7'*
DRL Reading RPB #3 Reading C. G. Long B. Grimes RPB p--DRL RPB #3 DRL omcE>
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6 OATE >
Fnrm AEC.318 (Rev. 4-53) mammmmtw2 na
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