ML20008F912
| ML20008F912 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 05/04/1981 |
| From: | Hoffman D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| TASK-04-02, TASK-4-2, TASK-RR NUDOCS 8105120303 | |
| Download: ML20008F912 (37) | |
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General offices: 212 West MicNoen Avenue, Jackson, MI 49201 * (517) 788 4550 D
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Director, Nuclear Reactor Regulation f
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xb Operating Reactors Branch No 5 De(cfi [Td '
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US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-155 - LICENSE DPR BIG ROCK POINT PLANT - SYSTEMATIC EVALUATION PROGRAM TOPIC IV-2, REACTIVITY CONTROL SYSTEMS DESIGN AND PROTECTION AGAINST SINGLE FAILLTES By letter dated Dece=ber 15, 1980, the NRC requested infor=ation concerning the design of the reactivity control systems at Big Rock Point. Attached Appendices A, B and C are provided in response to this request. Appendix A provides our specific responses to the questiens raised in the December 15, 1980 letter.
Appendix B provides a failure codes and effects analysis for the Big Rock Point control rod drive system. Appendix C provides an analysis of the effects of a single uncontrolled rod withdrawal in the Big Rock Point reactor.
David P Hoffman (Signed)
David P Hoff=an Nuclear Licensing Administrator CC Director, Region III, USN2C NRC Resident Inspector-Big Rock Point oc0481-0350s-43 O
l 810512o3o3
4
. CONSUMERS PCT ='ER COMPANT BIG ROCK POINT PLANT Response to'51C Request for Information SEP Topic IV-2 Contents-SLT ARY APPENDIX A - Answers to Questions APPENDIX B - Failure Modes and Effects Analysis APPENDIX C - Control Rod Withdrawal Analysis 4
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nu0481-0350a-43 April 1981 S
9 SDD!ARY This report was prepared to respond to an NRC request for information on SEP Topic IV-2, Single Failures in the Reactivity Control Systems, for Big Rock Point. The answers to the questions are provided in Appendix A.
To provide-the response, a Failure Modes and Effects Analysis was performed on the control rod drives and related control and actuation systems. This analysis is given in Appendix B.
The failures identified by this analysis that potentially have the most severe consequences are a failure of a collet locking mechanism which allows a rod to drift out of the core, and a failure in the electrical system that would cause a control rod to be continuously withdrawn when the operator attempts to withdraw the rod only a single notch.
Appendix C provides an analysis of the effects of a rod withdrawal on the fuel at Big Rock Point. Using the XN-2 critical power correlation (Reference 3 of Appendix C), the calculated CPR resulting from the rod withdrawal is 1.1974.
The proposed lower limit on CPR from Reference 5 is 1.32.
The calculated CPR also falls below 1.225, the CPR for which Reference 3 makes a 95/95 statement (95% confidence that 95% of the fuel pins will not experience departur,e from nucleate boiling). Thus, there is a reasonable probability that a few fuel pins in the two assemblies with a CPR less than 1.225 will experience boiling transition and fail.
I nuo481-0350a-43
.~
1 i
i APPENDIX A Answers to Questions Question 1 i
Describe the single failures within systems used for reactivity control which can:
a.
Cause an inadvertent reactivity insertion.
b.
Cause a single or combination of rods to be positioned in other than the design sequence. For PWRs this should include consideration of single rod withdrawal / insertions which can result from a single equipment component failure.
Response
The response is broken down into two parts: Failures that will not do anything without an initiating event (such as the operator attempting to move a control rod) and failures that will cause a rod movement without an initiating event. The answers given below refer to the item number on the list of failures in the single failure analysis (Appendix B, Tables B-1, B-2 and B-3).
la, Part 1: Failures that will cause a reactivity insertion without an initiating event: Drive Mechanism, Item 2; no items in the Drive Hydraulic System; Drive Electrical System, Items 25, 49, 51 and 53.
These failures may be categorized as:
a.
Failure of the collet locking mechanism to lock which would allow the rod to drift out of the core.
b.
Failure of the rod to settle onto the locking collet after a rod movement which would allow the rod to settle onto the collet at a later time, possibly one notch out of position.
la, Part 2: Failures that will cause a reactivity insertion only with an initiating event: Drive Mechanism, Item 1; Drive Hydraulic System, Item 24; Drive Electrical System, Items 1, 25, 30, 34, 49, 51 and 53.
These failures may be categorized as:
Failure of the drive to poison section coupling spud which a.
could cause a rod drop accident if the rod were to stick in the core and the operator failed to notice the rod not fol10 wing the drive.
b.
Spurious opening of a second selector valve while moving a control rod which would allow two rods to move at the same time.
nu0481-0350b-43 A-1
c.
Driving a rod continuously even with the jog override switch in jog mode.
d.
Failure of the rod to settle onto the locking collet which would allow the rod to settle onto the collet at a later time, possibly one notch out of position.
Ib, Part 1: Failure that would cause a rod to be mispositioned without an initiating event: Drive Mechanism, Item 2; Drive Hydraulic System, Items 9, 13, 14 and 27;' Drive Electrical System, Items 25, 49, 51 and 53.
These failures may be categorized as:
a.
Failure of the collet locking mechanism to lock which would allow the rod to drift out of the core.
b.
A single rod or all of the rods drifting into the core, Failure of a rod to settle onto the locking collet which c.
would allow the rod to settle onto the collet at a later time, possibly one notch out of position.
Ib, Part 2: Failurr, that would cause a rod to be mispositioned only with an initiating event: Drive Mechanism, Item 1; Drive Hydraulic System, Item 24; Drive Electrical System, Items 1, 5, 16, 25, 30, 32, 34, 36, 39, 48, 49, 51, 53 and 56. These failures may be categorized as:
Failure of the drive to poison section coupling spud which a.
could cause a rod drop accident if the rod were to stick in the core and the operator failed to notice the rod is not following the drive.
b.
Spurious opening ot a second selector valve while moving a control rod which would allow two rods to move at the same time.
Failure of the rod to settle onto the locking collet which c.
would allow the rod to settle onto the collet at a later time, possibly one notch out of position.
d.
Driving a rod continuously even with the jog override switch in the jog mede.
e.
Continuously inserting a control rod as soon as the selector valve is opened even though the rod positioning switch is on "Off."
Question 2 l
Delineate those design features which limit reactivity insertion rates and rod malpositions resulting from a single failure. Provide the appropriate circuit schematics showing these design features.
nu0481-0350b-43 A-2
Response
The reactor protective system is the only system available to limit reactivity insertion rates. There is no hardware available which will protect against rod malpositions unless the malposition would cause a reactivity insertion.
The RPS will protect against an inadvertent reactivity insertion in one of three ways that depend.on the reactor power level.
At' low power (less than about 4% of full power), if there is a large enough reactivity insertion to cause a 10-second period, the reactor will scram on short period.
If there is not enough reactivity to cause a 10-second scram, the reactor will trip when power level reaches about 40% of full scale. These functions are bypassed when the nuclear instrumentation is set to the full power range. At power operation, the reactor will trip at 120 i 5% of full power.
The circuit schematics are shown in Drawings 0740G30743, " Reactor Protection System" and 0740F30760, " Neutron Monitoring System." Note that this RPS drawing is not an actual schematic, but is an elementary diagram which shows the basic functional operation of the system. Both the reactor protective system and neutron monitoring system drawings are included in the standard set of Big Rock Point Piping and Instrumentation Diagrams (P&ID) which have been previously provided to the NRC.
Question 3 Provide or reference appropriate analyses to demonstrate that specified acceptable fuel damage limits are not exceeded in the event of any of the single failures identified in Item 1 above.
Response
A summary of failures and their effects that must be analyzed is given below:
Failure or Result of Failure Effects on Reactor 1.
Collet locking mechanism Allows a single rod to drift out of the fails to support rod.
core causing a positive reactivity insertion.
2.
A failure that prevents Allow a single rod to settle at some a rod to settle onto the time after the rod movement occurs, collet after movement.
causing a reactivity insertion.
The rod may be one notch out of position.
3.
Rod drive to poison section This is the beginning of a sequence coupling spud fails to hold of events that would cause a rod the poison section to the drop accident.
drive.
nu0481-0350b-43 A-3
Failure or Result of Failure Effects on Reactor 4.
Spurious activation of a Allows movement of two rods at a second selector valve when time. This results in one rod being attempting to drive a rod.
one notch out of sequence and a larger than expected reactivity insertion, either positive or negative.
5.
A failure that allows Allows continuous insertion or continuous rod motion even withdrawal of a single rod while with the " jog override" the operator is expecting only a switch,in " jog" mode.
single notch movement. This results in a larger than expected reactivity insertion, either positive or negative.
6.
A failure that results in All of the drives will drift into overpressurizing the drive the core, causing a negative cooling header.
reactivity insertion.
Any of-the above failures that cause a negative reactivity insertion should be of no consequence. Since Big Rock has no automatic power controller, any negative reactivity insertion during power operation will cause a power decrease with no loss of thermal margin.
If a single rod or all of the rods are inserted at zero power, the worst possibility would be to violate a. limit on rod worth or notch worth, but no fuel damage could result from such an incident.
Of the failures that result in a reactivity insertion, the failure of the coupling spud is specifically excluded from consideration by General Design Criterion 25.
The failures that' result in one rod being one notch out of sequence are of no consequence with regard to fuel damage.
In fact, the results of this type of failure are but a subset of the results of a failure where a rod is continuously withdrawn or of a rod drifting out of the core.
So any analysis for a failure where a rod moves more than one notch will bound the results for a failure where a rod is only one notch out of sequence.
The remaining failures result in a rod withdrawal that is either under the power of the rod drive system (Failure 5 above) or is drifting out by the force of gravity and normal seal leakage (Failure 1 above). At low power, l
with the short period trip and 40% of scale range trip in effect, the reactor will trip with one or the other of these trips before any fuel damage occurs.
At power operation the only trip available is the high flux trip at 120 5%
of full power. The effects of the rod withdrawal at power are identified in l
the attached analysis (Appendix C).
Quest g 4 Iden'ify the operating procedures, alarms, interlocks, or protection system actitns which must be used in limiting the consequences following a single nu0181-0350b-43 A-4
failure within systems used for reactivity control. Where equipment actions are required, indicate whether the equipment meets the criteria of IEEE-279.
Response
The equipment responses required to limit the consequences after a failure are:
(a) Short period trip with a reactor period less than 10 2 seconds.
This trip is bypassed when reactor power is greater than about 4% full power.
(b) High flux trip at 40% of scale range. This trip is also bypassed when reactor power is greater than about 4% full power.
(c) High flux trip at 120 i 5% of full power.
The equipment required does not meet all of the criteria of IEEE-279. For example, the reactor protection system does not have channel independence.
Additional information concerning single failures of the RPS is provided on Pages 9-11 of GE Report NEDC-20640, Rev 1, " Reactor Protection System Common Mode Failure Analysis" (submitted to AEC by Censumers Power Company letter dated October 21, 1974).
1 nu0481-0350b-43 A-5
APPENDIX B Control Rod Drive Single Failure Analysis SYSTEM DESCRIPTION To understand the single failure analysis, a basic understanoing of the Big Rock Point control rod drive system is required. The following discussion describes the major components of the system. For brevity, some of the minor system components have been excluded. Note that the piping drawing for this system is Drawing M-122 in the standard set of Big Rock Piping and Instru-mentation Diagrams (P& ids) which have been previously provided to the NRC.
CONTROL ROD DRIVE SUCTION During normal plant operations, suction is taken from the discharge of the condensa,te pumps. Pressure switch PS 626 on the condensate pump discharge header will switch the control rod drive suction to the condensate storage tank if the condensate discharge pressure falls below 50 psig. PS 626 does this by controlling the operation of Control Valves CV 4016'(suction from condensate pumps) and CV 4090 (suction from condensate tank). Suction to the two control rod drive pumps is through a common header.
CONTROL ROD DRIVE PUMPS The two control rod drive pumps are positive displacement pumps with a capacity of 25 gpm each. They are driven by 40 hp, 480 V ac motors. During normal operations, only one pump is on.
The second pump will automatically start on a reactor trip signal. There are annunciated alarms for both suction and discharge low pressure. The discharge of the two pumps is through a common header.
FILTERS There are two filters installed in parallel in the rod drive pump discharge line. Only one filter is normally in service at a time. There is an annun-ciated alarm for high-filter differential pressure at 20 psig.
FILTER OUTLET The filter discharge branches into two lines.
One line supplies the control rod drive cooling and driving headers and the other line supplies the scram accumulator charging header.
O CONTROL VALVE CV NC 18 This valve is installed in the line from the filter to the drive headers. The pressure tap, which controls the valve, is in the line going to the accumu-lator charging header. The valve controls the pressure in the accumulator charging header at reactor pressure plus 400 psid.
nu0481-0351a-43 B-1
CONTROL ROD DRIVE BYPASS VALVE CV NC 33 This valve is a manual remotely controlled (from the centrol room) valve that allows for variations in scram valve leakage or rod drive pump supply while maintaining the drive header supply pressure at react 1r pressure plus 200 psid. It is situated just downstream of Control Valve CV NC 18 and its discharge is piped through the regenerative heat exchangers to the reactor vessel.
CONTROL VALVES HCV NC 17 AND HCV NC 30 HCV NC 17 is downstream of where the bypass valve (CV NC 33) branches off and also downstream from where the drive header supply branches off. HCV NC 17 is a manually operared vcise that controls the drive header supply to reactor pressure plus 200 psid with Bypass Valve CV NC 33 at its optimum controlling position. The discharge from this valve splits to the drive cooling header and a return line to the reactor (via the same line that the bypass valve uses).
HCV NC 30 is on the line that returns to the reactor, downstream from HCV NC 17, but upstream from where this return joins the return from the bypass valve. HCV NC 30 is also a manually operated valve which controls the drive cooling header pressure at reactor pressure plus 30 psid.
DRIVE COOLING HEADER The drive cooling header feeds water through a check valve to the insert side of each of the 32 control rod drives. The drive seals are cooled by small amounts of water flowing past the seals and entering the reactor vessel.
MASTER CONTROL VALVES The master control valves allow flow to the drive header from the supply line and from the drive headers to a discharge header. The discharge header feeds back to the reactor vessel via the line from the regenerative heat exchangers.
The supply line branches off after Control Valve CV NC 18 and before Control Valve HCV NC 17.
The master control valves are arranged in two sets with four valves each, called Unit A and Unit B.
Only one control unit is valved into service at a time.
SV NC 13 D or H, when activated, will pressurize the withdraw header (only one will operate as they belong to different control units). SV NC 13 A or E will pressurize the insert header, C or G will depressurize the withdraw header and B or F will depressurize the insert header.
The withdraw and insert headers transmf.: the pressure to the withdraw and insert-parts on each of the control rod drives through the selector valves.
nu0481-03Sla-43 B-2 1
SELECTOR AND FLOW CONTROL VALVES Each drive is equipped with.a selector valve which allows flow in either direction between the insert header and the insert port on the drive and between the withdraw header and the withdraw port on the drive. Only one selector valve is opened at a time, so when the master control valves open to allow rod motion, only oae rod will move.
The flow control valves control the speed of rod motion for both withdraw and insert. Each drive has two flow control valves and three check valves installed between the selector valve and the insert port. Each flow control valve controls the speed in one direction only, so it is equipped with a bypass check valve to allow flow in the opposite direction. The third check valve allows flow from the drive cooling header to enter the insert port on the drive but does not allow the water from the drive headers (at a higher pressure) to enter the cooling header.
CONTROL ROD DRIVES A control rod drive is essentially a hydraulic cylinder with a collet locking device to hold the drive in position and to support the weight of the poison section while driving pressures are absent. The collet will unlock auto-matically on insert but must be unlocked before the rod can be withdrawn.
This is done by inserting the rod less than a full notch; the withdraw pressure will then hold the. collet La the unlocked position.
There is a ball shuttle valve that allows reactor water to enter the drive insert port when the drive insert pressure falls below reactor pressure. This is used when the rods are scrammed to complete the motion of the rod because the scram accumulators do not contain enough reserve to fully insert the drives.
CONTR0L ROD DRIVE OPERATION To insert a control rod, assuming Control Unit A is in operation, the follow-ing valve manipulations are made:
(1) Selector Valve CV NC 19 is opened by manual remote control, opening a flow path from the drive headers to their respective ports on the drive, (2) Control Valve SV NC 13 A opens which pres-surizes the drive insert header; simultaneously, SV NC 13 C opens to vent the drive header back to the reactor. These two actions begin the automatic sequence of events that the operator initiates by turning the rod motion switch, (3) water at a pressure of the reactor plus 200 psi enters the insert port, pushes the rod into the reactor and forces the water above the drive out into the drive withdraw header and vents it to the reactor, (4) cfter a preset a=ount of time has elapsed, SV NC 13 A and C will close to stop the rod =otion and SV NC 13 B will open, which allows water on the insert side of the drf.ve to vent to the reactor through the drive insert header, allowing the drive to settle onto the locking collet, (5) SV NC 13 B closes after another preset amount of time which ends the set of automatic actions, and (6) the operator closes the selector valve.
nu0481-0351a-43 B-3 T
To withdraw a rod, a slightly more complex sequence of valve operation is required:
(1) Selector Valve CV NC 19 is cpened as before, (2) the automatic sequence starts with Control Valves SV NC 13 A and C opening to insert the drive, (3) the drive is inserted by water pushing :he rod in from the insert header and water from the withdraw port venting to the reactor, (4) after a short preset a=ount of time (shorter than when an insert signal is given),
SV NC 13 A and C will close and simultaneously SV NC 13 D and B will open to reverse the flow of water, (5) water is now forced into the withdraw side of the drive and vented from the insert side; this pushes the drive down and bolds the locking collet in the unlocked position, (6) after another preset amount of time, SV NC 13 D will close, leaving B open to allow the rod to settle onto the locking collet, (7) after the preset settling ti=e, SV NC 13 B will close which ends the sequence of automatic actions, and (8) finally, the operator must close the selector valve to return the system to its initial condition.
For normal operation on rod withdra,al, the rod is first inserted enough to unlock the collet and then the rod is withdrawn, with the withdraw pressure holding the collet unlocked. The short insert ensures positive unlocking of the collet and minimizes wear in the drive. By design, however, it may be possible to withdraw the rod without first inserting it a short way if the contact surfaces of the collet and notch are mechanically clean.
SCRAM ACCUMULATORS There is one accumulator for each of 32 rod drives. Each accu =ulator is constantly charged with water from the charging header, with a check valve to prevent backflow. The accu =ulators have a horizontal flexible bladder with the water charge above the bladder and a nitrogen gas charge belcw.
SCRAM VALVES AND THE SCRAM DUMD TANK The outlets of the scram accu =ulator have a flew orifice to control the rate of rod insertion. Dcwnstream of the orifice is the normally closed scram inlet valve CV NC 09.
The scram inlet valve is piped directly to the insert port of the rod drive, thus bypassing all of the valves and piping used for nor=al control. The piping from the outle port on the drive has a branch that goes directly tc the scram outlet valve CV NC 10.
Thus, the scram controls are entirely independent from the normal centrols. The scra= outlet valve discharges to a scram du=p header which, in turn, discharges to the scram du=p tank. The scram du=p tank collects the water discharged froo the rod drives during a scra= operation. The scram du=p tank is vented through a check valve to the reactor with a one-=inute ti=e delay af ter a scram so that it will not put back pressure on the withdraw side of the rod drives after a scram.
SCRAM OPERATION The scram signal opens all 64 of the scram inlet and outlet valves, allowing water frem the accu =ulators to pressurize the insert side of each of the 32 drives and allowing water on the withdraw side of tne drives to vent to the nuG431-0351a-43 B-4
E scram dump tank.-
This starts the scram strohe on each of the drives. Since
-there is not enough stored energy in the accumulators to complete the stroke, the scram stroke is completed by reactor water entering the insert port through the ball shuttle valve. Since piping for the scram system is connected directly to the rod drives, the scram function will be available-despite any malfunction in the normal control system.
ROD SELECTION SWITCHES 4SI AND 4S2 These two switches each have a set of 6 contacts that are used to activate all of the 32 selector valves. Each contact completes one-half of a ' circuit to a set of 4 or 6 selector valves. When one contact is closed on.each of 4S1 and-4S2, the wiring is such that only one selector valve is energized and opened.
CONTROL UNIT SELECTOR SWITCH 4S4 l-This switch will complete the circuit to only the set of master control' valves that are to be used. The control valves in the unit that is not selected will not be energized.
ROD POSITION SWITCH 4S3 This switch controls the rod motion by controlling the Master Valves SV NC 13 A through H through a set of timed relay switches. The switch is labeled " Increase" to pull rods out and " Decrease" to push rods into the core.
J0G OVERRIDE SWITCH Normal operation is to move one notch on one control rod at a time.
In order to move the same or another rod, the relays must be reset by turning the rod motion switch to "Off."
The jog override switch, when set to "Run," will
~
bypass this function. This is done by' completing a circuit around the timed relay that controls the rod motion (either insert or withdraw). Thus, when the relay times out and would ordinarily break the circuit to the master j
control valves, the circuit is not broken because of the extra circuit through the switch, so the rod does not stop moving until either the jog override switch or the rod position switch is released or the rod reaches the end of its travel.
SWITCH AND RELAY OPERATION FOR ROD INSERT l
The following description of operation may be better understood by examining the simplified drawing of the rod drive electrical system shown on Figure B-1.
The selector valve for the drive chosen is opened by turning the Selector Switches.4S1 and 4S2 to the number-letter combination, which corresponds to the designation of the rod to be moved. The Unit Selector Switch 4S4 is turned to Unit A so solenoid control valves SV NC 13 A, B, C and D will be i
actuated while E, F, G and H will not be.
If Unit B were selected, the same sequence would activate Unit B and leave Unit A alone.
nu0481-0351a-43 B-5
,,+
-n
The Rod Motion Switch 4S3 is turned to " Decrease" (decrease reactivity or push rods into the core) which closes Contacts 1-1T on 4S3. This actuates Relays 4K3, 4K1 A and B, simultaneously. Relay 4K3 will not do anything until 1.2 seconds have passed when it will open the circuit to Relays 4K1 A and B, deactivating them. Relay 4K1 A closes the circuit to Control Valves A and C, inserting the rod. Rod insercion stops when Relay 4K3 times out which deactivates relay 4K1 A, de-energizing Control Valves A and C.
Relay 4K1 B will not initially actuate a control valve because it has two sets of contacts in series. Contact 3-4 closes when Relay 4K1 B is energized while simul-tane+5 sly Contact C-NC opens, so no circuit is completed. When Relay 4K3 times out and de-energizes Relay 4K1 B, Contect C-NC returns to the closed position while Contact 3-4 is held closed for a period of three seconds.
Thus, a circuit is created to Control Valve B, depressurizing the insert header to allow the drive to settle onto the locking collut. The end of the automatic sequence occurs when Relay 4K1 B times out at three seconds, de-energizing Control Valve B.
To make another rod movement, the relays must be reset by turning the rod motion switch to "Off."
The system is returned to its initial condition by turning the rod selector switches to "Off" (which closes the selector valve) and by turning the rod motion switch to "Off."
=
SWITCH AND RELAY OPERATION FOR ROD WITHDRAWAL The selector valvo for the rod is opened with the Selector Switches 4S1 and r
4S2. The automatic actions com=ence when the Rod Position Switch 4S3 is turned to " Increase" (increase reactivity by pulling rods from the core).
Contacts 2-2T, 3-3T and 4-4T on AS3 close. These initial actions are very similar to when a rod is inserted.
Relays 4K1 A, B and 4K3 are energized by a circuit created by Contacts 2-2T and 3-3T of 4S3 and by Contact 6-4 of Relay 4K5.
Relay 4K1 B does not open any control valves as yet.
Relay 4K3 has no normal active function for this scheme because Contact 6-4 of Relay 4K5 will time out and break the circuit to 4K1 A and B before 4K3 will do so.
Relay 4K1 A energizes Solenoid Control Valves A and C to insert the rod. Contact 6-4 of Relay 4K5 times out at 0.3 second, de energizing Relays 4K1 A and B.
Thus, the rod is inserted only 0.3 second instead of the 1.2 seconds that a normal insert lasts. The circuit to Control Valves A and C is broken by Relay 4K1 A while Relay 4K1 B creates a circuit to Control Valve B.
When Contact 6-4 of Relay 4K5 broke the circuit to Relays 4K1 A and B, Contact 6-2 of 4K5 created a circuit that energized 4K2.
Contacts 1-7 and 8-2 of Relay 4K2, along with Contact 4-4T of Switch 4S3, create a circuit to Control Valves B and D.
There are now two parallel circuits to energize Control Valve B.
Control Valves B and D are now open to withdraw the rod. Relay 4K2 will de-energize when Contact 6-a of Relay 4K4 times out and breaks the circuit. This de-energizes Control Valve D but Valve B is still energized through Contacts 3-4 j
and C-NC of Relay 4K1 B.
Thus, the insert header remains depressurized, F
allowing the drive to settle onto the locking collet. The final automatic action is Contact 6-4 of Relay 4K4 timing out, de-energizing Relay 4K2, which nuo481-0351a-43 3-6 l
SIMPLIFlED DRAWING 0F R00 DRIVE ELECTRICAL SYSTEM TAKEN FROM DRAWING 0740F30731' SHEET 2
. 4S3 2$
2T TD0
-.3 4..
E m" l20 VAC 3
SAFETY INTERLOCKS 3 SEC
'"4 4T r"n 5 l
j 4K2 mN IT
'N 614K5 61 TD0 W
N 2
TDC.3 SEC 41 3 SEC 4K3. 2 3-NC 3
g 4KIA
.5 SEC 1T :4SS. 2T 2
- g 484 2T
- 4K4 *>4K5
- 4K2
%4KI A kyKlB' 4K3 kC
![E kD kF A
G B
ll SWITCH 4S3 SWITCH 4S4 SWITCH 4SS POSITION CONTACTS CLOSED POSITION CONTACTS Cl0 SED POSITION CONTACTS CLOSED OFF NONE UNIT A l-IT,3-3T,lA-IAT J0G NONE DECREASE l-IT RUN 1-lT,2-2T INCREASE 2-2T,3-3T,4-4T UNIT B 2-2T,4-4T,2A-2AT IrFY:
NOTE: SWITCH AND RELAY CONTACTS ARE SHOWN
--Il-SWITCH OR RELAY CONTACTS WITH 4S4 ON UNIT A, 4SS ON J0G AND 4S3 ON OFF ggy
'///A-SOLEN 0ID VALVE (SV NC 13 A TilROUGil H) ai
closes Control Valve B.
To make another rod motion, the relays must be reset by turning Switch 4S3 to "Off."
To return the system to its initial condition, the selector valve must be closed by turning Switches 4S1 and 4S2 to "Off" and by turning the rod positioning Switch 4S3 to "Off."
SINGLE FAILURE ANALYSIS The single failure analysis for the control rod drive system is presented on Tables B-1, B-2 and B-3.
This is essentially a Failure Modes and Effects Analysis for all of the components in the control drive system as identified in a controlled set of Big Rock Point P& ids.
The analysis is divided into three parts: Table B-1 for the drive mechanism, Table B-2 for the hydraulig system and Table B-3 for the electrical system.
nu0481-0351a-43 B-7
o 1
Appendix il Tablo 11-1 Control Itod Drivo Hochanism.
rquipment failuro Symptoms, Effects &
- Compensa t f eng Errects on AL ID Modo _
_ Dopenderit failur g Detection Prov i s i oris System Remarks 1
Coup l i tig Un-if the rod is stuck, Ovu rt rave l Nono.
Rod can be to poison coupled the poison section a: hoc k, rinc l ea r driven in.
If section will not follow the instrumentation, poison section drivo,. the position d rop s, it indication will be in could causo a o r ro r, reactivity in-sortion.
2 t ockirig Un-Rod may drif t in or Itod pos i t ior?
May cause an Roror to NitC collet latched
- out, indication, undetected ro--
letter dated activity in-1/11/fl0 and sortion.
CP Co lotter datod'$/9/80.
G rpula1-0352a-71 t
1
t 1
Appendix B lable H-2 Control Rod Drive flydraulic System Equipment railure Symptoms, Effects &
Compensating Errects on
_No_
ID Mode Dependent railures Detection Provisions System Remarks 1
PS-626 As is Possible loss or CRD Annunciated Operator may Possible loss Sc ram s t i l l (M106) pump suction from alarm.
restore suction of rod drive availablo, but condensato pump dis-to condensate and cooling scram timo may cha rge at 50 psig storage via
- flow, be slow due to
( dec rea s ing )
IIS 7022 (M106).
excess seal di scha rgo pressure.
leakage.
Rod drive seals may rail due to lack of cooling.
2 At 50 psig (increas-Position indi-
- Nono, ing) on condensate cating lamps on d i sc ha rge, CRD pump CV 4090 ac suction will not CV 4016 (M106).
swi tch f rom condon-sato storago.
3 No Possible loss of CRD Annunciated Operator may Possible loss Sc ram st i l l contact pump suction, a l a rm.
restore suction of rod drivo available, but mado to condensate and cooling scram timo may storage via
- flow, be slow due to HS 7022 (M106),
excess seal leakage.
4 CV 4090 Closed Loss of CRD pump suc-Annunciated Operator may Possible loss Sc ram s t i l l (M106) tion ir condensato alarm.
restore suction or rod drive available, but d i scha rgo < So psig, to condensato and cooling scram timo may storage via flow.
be slow duo to HS 7022 (M106).
excuss seal l ea kago.
Open Nono.
6 CV 4016 Closed loss or CRD pump suc-Annunciated Operator may Possible loss Scram still (M106) tion ir condensato alarm.
restore suction or rod drivo available, but-d i scha rge > $0 psig.
to condensate and cooling sc ram timo may storage via
- flow, be slow due to HS 7022 (M106),
excess seal leakage.
7 CV 4016 Open None.
(M106) rp0481-03S2b-71
i I
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Equipment failuro Symptoms, Effects &
Compensating Effects on
_No ID Modo Dependent f a i lures Dolection Provisions System Remarks 8
Pis A o r u Stop Pressure in rod drive Annunciated Operator may Possible loss Sc ram s t i l l (M106) running system decays,
- alarm, sta rt other of rod drivo available, but pump.
and cooling scram timo may
- flow, be slow due to excess seal leakage.
9 Platt o r A Spurious Pressure surgo in rod PI RD 19 (M122)
CR0 pump dis-The rod d rive.
(M106) start drive system.
displays pros-cha rgo roller cooling header sure, possible valves may lift, will overpres-annunciated Operator may surize which alarm in cooling trip the pump could push all
- header, or open flow of the rods in, control valve NC33 (M122).
10 CRD pump Rupturo loss of rod drive and Annunciated None.
Rod drives a re Sc ram s t i l l suction or seat cooling pressure.
alarm.
frozen in posi-available. but d i scha rge Rod drive seals would tion.
scram timo may heador fait due to lack of be slow due to (M106) cooling.
excess seat leakago.
11 dels RD 39 Switch Loss of indication of 10 the filter Operator may Rod drives may Scram still (M122) contacts fi l te r ope rabi l i ty, plugs: low flow valvo in the freezo in posi-available, but fail open Possible loss of rod indicated by other filtor.
Lion.
scram t imo may drive seals due to flRD 36 (M122) be slow due to lack of cooling if Annunciated excess seal the filter plugs, a l a rm rod d rivo
- leakage, tempe ra t u ro.
12 CV NC 18 Closed Loss of rod drivo and Low cooling flow Nono.
Rod pGsitions Sc ram st i l l (M122) seat cooling pres-indicated by a re f roze64, available, but su re.
Possible loss F1 RD 26 scram timo may of rod drive sea l s.
(M122).
Iow be slow due to AP indicated by excess seal dPl RD 01 leakage.
(M122). Annuu-c i a ted a la rm o f rod drive temp-o ra tu re.
13 Open Pressure surge in rod liigh pressure &
Manual adjust-Rod drives may drive & cooling flow indica-monts of flow drift in via headers.
Lions in control valves normal seal fl RD 36 &
HCV NC 30 & 17.
leakage.
P1 IA 05 (M122).
rpol81-0352b-71
3
[quipment Failuro Symptom, Criucts &
Competisa t i ng Errects on
_NrL ID MotJL DonondeDt failuroL Dole 311mi Provisions System Remarks 14 CV NC 33 Closed liigh pressure in rod liigh pressure &
Manual adjust-Rod drivos may (MI22) drivo & cooling flow indica-monts or flow drif t in,
- headers, tions in control valves r1 HD 36 &
IlCV NC 30 & 17.
P1 1A OS (M122).
I 's Open toss of pressure in Low cooling flow Manually close Rod drives a re Scram still rod d ri vo & coo l i ng indicated by block valves.
frozen in posi-available. but headers.
Possible II HD 36 tion.
scram timo may loss or rod drivo (M122),
low be slow due to seals.
AP indicated by excess seal dPl HD 01 leakage.
(M122). Annun-ciated alarm or rod drivo temp-o ra t ta ro.'
16 SV NC 13 il Closed On withdraw signa l-Itod does not Manually switch Withdraw not or D loss or ability to wi thd raw on control units.
available untJI (M122) wi thdraw rods,
- demand, control units are switched.
17 SV NC 13 11 Opon Continuously pressur-fxcessivo flow Manually switch Rod wi thd rawa l Sc ram ava i l-or D izo the withdraw at il RD 8 5 control units.
may be sticky ablo.
4 (M122) heador to all selec-(M122) during becau*o un-tor va lves.
during rod in-latching may
- sortion, not opera to.
Rod insertion may be ' slow.
16 SV NC 13 C Closed On Insert signal:
Hod does not Manually switch ' Hod wi thd rawa l Sc ram ava i l-or C loss of ability to movo on insert control units.
may not operato able.
(M122) to insert rods.
signal, may not
'becauso un-move on with-latching does d raw.
not opera to.
Rod insertion doos not oper-ato.
19 Open Continuously pressur-Excessive flow Manually switch Rod insert will ize the insert header at F1 HD 8 5 control units.
ope ra to, rod 4
to all selector (M122) during wi thd rawa l may
- valves, rod wi thdrawa l.
be slow.
20 SV NC 13 C Closed Unable to depressur-low riow at Manually switch ' Hod insert not Sc ram ava l l-ar G izo the wi thdraw Fl HD is$ (M122) control units, available. Hod
- able, header.
on insort, wi thdraw may not opora to, rp0881-0352h-71 4
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Equipment fafluro Symptoms. Errects 1k Compensating Errects on J o_
10 Mode Dependent failureg_
Detection P rov i s ionL System Remarks 31 Open None.
None.
Rod insert is Scram time not too fast for a rrec ted.
d ri ve.
32 itow con-Closed
- None, ir fully None.
Rod wi thd raw i s Scram not trol valvo closed: rod too slow for arrected.
V2 (M122.9 drive is stuck, d ri ve.
33 open None.
None.
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e rp0881-0352b-71 4
1 Appendix 8 lable B-3 Control Hod Drive Electrical System Equipment railure Symptoms, Errects &
Compensating Errects on
(
_yo 10 Modo Denendent failures Detection Provisions System Hemarks 1
Humber Closed Possible spurious Hod position Ino rod can be Possible to 4
selector activation of a indication will moved back to d rive two rod s switch 4S2 selector valve change for. two its correct a t a t i me.
contacts (SV NC 13) when rod rods, not just position.
1-11, 2-2T selection switchop one when a rod 3-31, 4-4T, 451 end 452 a re is moved.
5-51 or moved.
6-6T 2
Open Se l ec to r va l vo re-Rod position Hono.
Seve ra l rods Sc ram i s s t i l l quired to movo rod indication will a re ' f rozen in available.
may not be actuatud, not move, current posi-tiGn.
3 Number Closed Possible spurious indicating Position indi-Only the selector activation or a light may como cation will co rrec t rod is switch 4S2 rod selection indi-on.
move for the moved.
c ntacts cating light when rod correct rod 1. I, 8-81, selection switches only.
9-91, 4SI 4S2 a re moved, t
10-10T, d
11-111, or 12-12T 4
Open Selection light does Light is not on Position indi-Rod moves nor-not como on when it when it should cation will
- mally, should be, be, chango when rod is moved.
5 totter Closed Possible spurious Hod position the rod can be Possible to selector activation of a so-indication will moved back to drive two rods switch 4SI lector valvo change for two i ts correct a t a t i me.
contacts (SV NC 13) when rod rods, not Just position.
1-1T, 2-2'i,
selection switches one when a rod 3-31, 4-4T, 4S1 and 4S2 a re is moved.
S-5T or moved.
6-6T 6
Open Selector valvo re-Rod position None.
Seve ra l rods Sc ram i s s t i l l qui red to move rod indication will a re f rozen in available.
may not be actuated, not move.
curreni posi-tion.
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3 Equipment ra i l u re Symptoms, Errects &
Compensating Errects on
_No_
ID Mode Dependent railures Detection Provisions System Hemarks
'r 15 Switch 4S3 Closed Holays 4K4 and 4K5 Unable to with-Hono.
Hod withdraw contacts will energize ared d raw rods be-not available.
2-2T time out.
Holay 4K2 cause relays will be energized have not been b rie f ly.
No reset.
control valves will open.
16 Switch faS3 Open On wi thdraw, relays The selected None.
Withdraw not contacts 4 K4 & 4 KS a re ene r-rod moves in available.
2-2T gized through con-continuously, tacts 3-3T or 4S3.
not out a This circuit is bro-single notch, ken when 4K5 timo de-lays out at.3 j
seconds. The relay is then reset and creates the ci rcuit d
again.
This will continee indori-nitely. Thus relays 4KI A pauf 4KiB a re energized completing ci rcuits to SV NC 13 A & C or E & G and D or i flolay 4K3 will time out and be reset by relay 4KS timing out, resetting and recreating the energizing circuit.
The end result is the control rod selected will be continuously inserted instead or withdrawn a single notch.
17 Switch 4S3 Open on wi thdraw, relays Hod may not None.
Withdraw not 4KI A and 8 K10 are not wi thd raw, available.
contacts 4
3-3T energized. Thus the
" tempora ry insert" signal is not given so the drive does not unlatch before the wi thd raw signa l.
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Equipment failure Symptoms, Errects &
Compensating Errects on
_gg_
19 Modo __
Dependent failure 1_
Detection P rovi s ions System Remains 31 Switch 4S$
Open On insert with " jog Rod does not Rod may"be Continuous in-contacts override" relay 4k3 continuously
" Jogged in, sortion not 2-2T is not bypassed, so
- insert, available, relays 4k1A and 4K18 are de-energized when relay 4K3 times out.
Relays 4KIA and 4K18 control the solenoid valves to insert rods.
Thus the in-sort signal times out no rma l ly.
32 Closed on insert, without Rod does not Switch 4S3 may Rod may be in-
" Jog override," relay stop inserting, be turned to sorted too rar 4k3 is bypassed such orr.
but may be that relays 4KIA and withdrawn to 4K18 do not de-ener-correct posi-gize when relay 4K3
- tion, times out.
Relays 4KI A and 4KlB control the solenoid valves that insert rod s.
Thus the road is con-tinuously inserted.
33 Relay 4K4 Open On withdraw, relay Rod does not None.
Rod withdraw contacts 4h2 i s not ene rg i zed.
wi thd raw.
not ava ilable.
4-6 Relay 4k2 controls the solenoid valves that wi thdraw rods.
Thus, the rod does not wi thdraw.
Fail-ure is the same as the relay sticking in energized state, rpO481-0352c-11
t' 7
Equipment Failure Syoptoms, Effects &
Compensating Effects on
_No_
ID Modo Dengndgat Failures Det9ction Provisions System Rema rk s 384 Closed on wi thdraw, relay Rod will stop Switch 4S3 may Rod will be 4K2 is energized withdrawing for be turned of f.
wi thdrawn too norrally but it is a short period far but may be not do-energizec when of timo and inserted to its it should be.
Felay then continu-correct posi-4K2 controls the ously wi thdraw.
tion.
solanoid valves that withdraw rods.
This failuro does not a rrec t the "sottle" signal, so the con-trol valves will be sligned such that the drive riow will go directly to the dis-chargo header while the settle" signal lasts.
After
" settle" is termi-nated, the rod will continue to withdraw.
This failure is the sano as the relay sticking in the do-energized state.
35 Relay 8h5 Open On wi t hd raw, relays Rod may not None.
Rod withdraw t
contacts 4KI A and 4K18 are wi thd raw be-not available.
4-6 not ene rgized. Rolay cause it does 8 KI A controls the not unlatch, 4
solenoid valves to insert rods. Relay fK18 controls the l
" settle" rods, rp0881-0352c-71 4
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10 Equ!pment Failure Symptoms, Errects &
Compensating Errects on
_Mo_
ID Mode Dopendent Failures
__ Delegtlon P rovi s ions System Remarks 45 Relay 4K2 Stich in On w i t hd raw, solenoid Rod will not None.
Rod withdraw de-ene r-va lves SV NC 13 D o r wi thd raw.
not available, gized H will not energize state to wi thdraw rods.
During " settle" af ter the wi thd raw, SV NC 13 8 or I will not ene rg i ze to a l l ow settling.
46 Rolay 4K2 Stick in On withdraw, SV NC 13 Rod may not None.
Rod withdrawal ene r-D or H will energize wi thd raw be-may not be gized p rema tu re l y.
During cause it may available, state the " tempora ry in-not insert to sort," withdraw riov unlatch to will go directly to collet.
the discha rge header.
This also happens during " settle."
47 Relay 4K1A Open On insert or withdraw Rod does not None.
Rod movement Sc ram s t l I l contacts
( du r i ng"" tempo ra ry insert or with-not available, available.
3-4 insert, ) the sole-d raw.
nold valves that in-sert a re not ener-rized. Failure is the same as the relay railing in the de-energized state.
48 Closed Solenoid control Rod vill insert valves SV NC 13 A & C as soon as rod o r E 4 G a re cont in-selection uously energized, switches 4St regardless or switch and 4S2 a re 453 position.
Fall-
- set, ure is tt:e same as the re lay ra i l ing in the energized state.
49 Relay 4k18 Open On insert or with-Rod position None.
Collet may not contacts draw, solenoid valve indication may latch af ter rod 3-4 SV NC 13 8 will not show the rod one
- movement, energize to " settle" notch out or the rod af ter move-position af ter i
- ment, movement, rp0481-0352c-71
e 11 Equipment Failure Symptoms. Errects &
Compensa t i ng Errects on
_Ng_
10 Mode __
Denendent failures Detee'.ign Provisions System Remarks 50 Relay 4K1B Closed Solenoid valves None.
None.
contacts SV NC 13 8 or I are 3-4 energized regardless of position or switch 4S3.
With rod move-ment the valve will close when contacts C-NC of relay 4K18 open so the rods will move normally.
51 Relay 4K18 Open Solenoid valves Rod position None.
Rod may be mis-contacts SV NC 13 8 o r F wi l l indication may positioned by C-NC not energize when the show the rod one notch.
A settle" signal is one notch out given.
or position be-cause it has not settled to allow the collut to Iatch.
52 Closed Solenoid valves Rod will not None.
Rod movement Sc ram st i l l SV NC 13 8 o r F wi l l insert and may not available.
available, be energized prema-not withdraw turely on rod move-because it did ment.
On insort, not unlatch the this means that the collet.
insert flow will go directly to the dis-charge herder.
53 Relay 4K1B Stick in Solenoid control Rod position Rod ma'y be mis-de-e ne r-valvo SV NC 13 8 or F indication may positioned by gized will not o show the rod one notch,
" settle." pen on state one notch out or position bo-cause it has not settled to
.i allow the collet to latch.
54 Stick in Solenoid control energized valve SV NC 13 8 or r state will not open on
" settle."
rp0481-0352c-71
~
.+.
a 0
12 j
Equipment railure Symptoms. Effects &
Compensating Errects on
- _go, ID Mode Dependent f a i lu res Detection Provisions System Rema rk s 55 ftelay 4K3 Open Relays 4KIA and 4K18 Rod will not None.
Rod movement Scram still contacts will not be ener-insert or with-not available, available.
2-3 gized.
Thus, the d raw, solenoid valves that insert rods will not be energized.
Fall-ure is the same as if the relay railed in the energized state.
56 Closed On insert, relays Rod will not Switch 8S3 may Rod may be with-4 4KI A and 4Kl0 do not stop inserting be turned off d rawn to i t s.
time out with 4K3.
On insertion.
to stop i nse r-correct posi-Thus, the insert sig-
- tion, tion, nal is continuous.
On withdraw the fa il-ure acts normal since relay 4k5 controls the timing. Failure i s the same a s i f the relay failed in the de-energized sta te.
rpO481-0352c-71 l
e s
APPENDIX C Control Rod Withdrawal Analysis (Extracted From Reference 5)
This analysis describes the effects of a single control rod withdrawal on the Big Rock Point reactor. The rod withdrawal.is caused by one of two possible events:
(1) An equipment malfunction will cause a rod to be withdrawn con-tinuously when the operator attempts to withdraw the rod one notch; and (2) the locking collet fails and the rod.will drift out of the core under the force of gravity, restrained by the friction of the displaced water leaking through the drive seals.
The assumptions used in this analysis and the justification for their use are:
1.
The reactor is in equilibrium with respect to Doppler and in-channel void feed-back mechanisms. This is allowed because the rod motion is slow when compared to the time constant for fuel heat transfer.
2.
The reactor power stays in equilibrium with the steam drum and the rest of the plant so the inlet subcooling stays in step with reactor power. This is only partially true for the rod withdrawal by the control system but the subcooling will rapidly catch up with the power level and come to equilibrium. However, constant subcooling is a less conservative assump-tion than equilibrium subcooling. From Table C-1, the core MCPR is 1.2862 with equilibrium subcooling, while it is only 1.3245 with constant subcooling.
3.
The feedback due to xenon is not allowed to vary. This is because the rod withdrawal !.s much faster than the time it would take for xenon to come to equilibriuu. Also, xenon would depress the increase in power so freezing the xenor. (allowing a greater increase in power) will be conservative.
4.
The reactor protective system is not allowed to scram the reactor at 120 5% of rated power. Since the power increase is localized around the rod, the excore detectors, which sense reactor power for the RPS, may not "see" the power increase.
5.
The initial condition that gives the most limiting results is at beginning of a cycle at 102% of rated power. This is because the core will have the highest rod density and, due to the high power, will have the lowest margin to fuel damage limits.
6.
The uncertainties in the radial power distribution and the amount of reactor power increase are accounted for by applying a 5% engineering factor to the final (rod withdrawn) power level. The uncertainties in the axial and local power distributions are accounted for by applying another 5% engineering factor to the peak heat flux.
Tha analytical tool used for this calculation is GROK, a three-dimensional nodal reactor simulator with full thermal and hydraulic feedback. GROK is nu0481-0353a-43 C-1
based on FLARE (Reference 4) but it has been tailored for use at Big Rock Point.
It can be used for reactivity inventory, design, core follow and chermal limits calculations. To evaluate fuel damage limits, the critical power ratio is calculated using the XN-2 correlation (Reference 3).
The analysis starts with a search for the control rod pattern that would be critical at 244.8 NWt (102% of plant rated 240 MWt) at the beginning of Cycle 17.
The rod patterns searcF 3d on are taken from those presented in the Cycle 17 Physics Package (Reference 1).
Once the critical rod pattern is found, one of the pair of rods that is farthest inserted is pulled out of the core and the new power level is calculated. The calculated power with the rod out is then increased by 5% for an evaluation of fuel damage limits by the critical power ratio calculation.
With the rod fully withdrawn, reactor power increases to 336.1 MWt (which includes the 5% factor) and six assemblies end up with a CPR less than the acceptable CPR of 1.32 which is proposed in Reference 3.
These six assemblies all have CPRs less than 1.296 for which the 99/99 statement can be made (Reference 3).
99/99 means that, with 99% confidence, 99% of the fuel rods will not experience DNB. Two of the six assemblies have CPRs less than 1.225 for which a 95/95 statement can be made. The assemblies and their CPRs are given in Attachment 4.
The CPRs for the 99/99 and 95/95 statements were derived from the one data set of the five data sets available in Reference 3 that gave the most conservative result. That data set containea 130 data points. All of the data sets combined had a total of 471 data points.
If all of the data were used, the 95/95 statement could be made for a CPR of 1.141 and the 99/99 statement could be made for a CPR of 1.212.
Using these criterion, only one assembly is less than the 99/99 CPR and no assemblies are less than the 95/95 CPR.
There are at least two factors not accounted for in this analysis that would minimize the effects of a rod withdrawal. One is that the operator will receive at least one alarm (the bypass valve opening) that he must respond to.
Since the control rod position indication will remain operable, the operator should be able to diagnose the problem. The other factor is that the plant would probably not be able to support a power level of 320 MWt.
Either the feed pumps will run out trip on low suction or the condenser will trip on low vacuum.
nu0481-0353a-43 C-2
i TABLE C-1 Results of Analysis Initial Final Assembly MCPR MCPR Comments G227 1.8890 1.2862 No Uncertainties G412 1.7550 1.3011 Initial Power 244.8 Wt Final Power 320.1 W t From Fiche 2 G227 1.8890 1.1974 With Uncertainties G412 1.7550 1.2237 Initial Power 244.8 Wt G315 2.2376 1.2617 Final Power 336.1 Wt G311 2.2809 1.2711 From Fiche 3 G301 2.0546 1.2830 H102 2.0577 1.2905 G227 1.8890 1.3245 No Uncertainties G412 1.7550 1.3533 Constant Subcooling Initial Power 244.8 Wt Final Power 301.1 Wt From Fiche 2 i
t nu0481-0353a-43 C-3 a
-,,,-w.
,,-w.,
---,.-n
WP o
References for Control Rod Withdrawal Analysis 1.
Big Rock Point Cycle 17 Physics Package UFI 740/22*13*32 PERFIL B.C.17.801205 I
2.
Design Review by Glen Seeburger; Rerun core follows Cycles 13 through 16-for Big Rock Point. UFI 740/22*13*21 PERFIL B.Z.GR0K.801027 3.
XN-75-34, "The XN-2 Critical Power Correlation, Revision 1, August 1, 1975, K. Galbraith and J. Jaech 4.
Delp, DL, et al, " FLARE - A Three-Dimensional Boiling Water Reactor Simulator," GEAP-4598, July 1964 5.
Design Review by Glen Seeburger; Analyze a rod withdrawal for Big Rock Point. UFI 740/22*13*20 PERFIL B.C.17.810313 l
l I
(
nu0481-0353a-43 C-4 i