ML20113G551
| ML20113G551 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 02/21/1990 |
| From: | Bell H GEORGIA POWER CO. |
| To: | |
| Shared Package | |
| ML20092F288 | List:
|
| References | |
| CON-IIT05-191-000A-90, CON-IIT5-191-A-90, RTR-NUREG-1410 LO-LP-12101-20, NUDOCS 9202210469 | |
| Download: ML20113G551 (64) | |
Text
r GEORGIA POWER POWER GENERATION DEPARTMENT VOGTLE ELECTRIC GENERATING PLANT TRAINING LIESSON P p TITLE:
RHR SYSTEM NUMBER:
LO-LP-12101-?O-C PROGRAM:
LICENSED /NON-LICENSED OPERATOR TRAINING REVISION:
20 SME:
H. BELL DATE:
2/21/90 APPROVED:
O DATE:
~bAP Nf90 A
V 6 v
v I.
LESSON FORMAT A.
Lecture with visual aids II.
MATERIALS A.
Overhead projector B.
Transparencies C.
White board with markers D.
VHS video tape player and monitor E.
Most recent revision of:
1.
13011 RHR System 2.
18019 Loss of RHR III.
EVALUATION A.
Written or oral exam in conjunction with other lesson plans IV.
REMARKS A.
Performance-based instructional units (IUs) are attached to the leeson plan as student handouts. After the lecture on RHR System, the student should be given adequate self-study time for the IUs.
Ino instructor should direct self-study activitiek and be available to answer questions that may arise concerning the IU materis'.. After self-study, the student will perform, simulate, observe, or discuss (as identified on the cluster signoff criteria lina) the task covered in the instructional unit in the presence of an evaluator.
B..This lesson plan may be used for Licensed or Non-Licenned Operator programs. Objectives are included for both.
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LO-LP-12101-20-C e
Licensed Operator Objectives for this lesson plan can be found in the Licensed Operator System Master Plan Section 2.3 (Qualification Signoff criteria)
Latest Revision of Cluster 12 RHR SYSTEM 2
LO-LP-12101-20-C 9
e Non-Licensed Operator Objectives for this lesson plan can be found in the Non-Licaased Operator System Hanter Plan Section 2.3 (Qualification Signoff criteria) 7atest Revision of Cluster 12 RHR SYSTEM e
3 f
m.
LO-LP-12101-20-C REFERENCES 1.
Plant Vogt19 Procedures
- 13011-1, Rasidual Heat Removal
- 17006-1, Annunciator Response Procedure ALB06
- 14805-1, Residual Heat Removal Pump.and Check Valve Inserv' ice Test 2.
Technical Specifications - 3.4.1.3 RCS/ Hot Shutdown
- 3.4.1.4.1 RCS/ Cold Shutdown - loops filled
- 3.4.1.4.2 RCS/ Cold Shutdown - loops not filled
- 3.5.2 ECCS/T 2 350 degrees F avg
- 3.5.3 ECCS/T 350 degrees F RF/hig$ Oa<er level)
- 3.9.8.1 t
- 3.9.8.2 RF/ low water level) 3.
Vogtle Text, " Residual Removal System", Chapter 10a 4.
Residual Heat Removal System Plant Manual, Chapter 32 6.
Piping and Instrument Diagrams:
~X4DB115-1 CVCS System
- 1X4DB116-1 CVCS System
- 124DB122-1 RHR System 7.
Commitments:
- IEB 80.012 Decay Heat Removal operability (commitment)
- SOER 85.004 Loss or degradation of residual heat removal capability in PWRs (commitment)
- SER 84.079 Loss of shutdown cooling due to inaccurate level indication (commitment)
- NUREG 0927 Water hammer (cournitment)
- SER 86.035 Extended loss of shutdown cooling due to steam binding of shutdown cooling pumps (commitment)
- IEN 86.101 Loss of RHR events at PWRs (commitment)
- CE 1851 RHR shutdown cooling suction isolation valve inspections (commitment)
- IEN 87.023 Loss of decay heat removal during low reactor coolant level operation
- NOP.464 Mid-loop operation Concerns
- NUREG 1269 Detailed description of Diablo Canyon Loss of RHR
- IEN 88.036 Possible sudden loss of RHR
- FF 86.004 Mini-flow setpoint changes
- FF 88.014 RHR Operation with RC$ Level at Mid-loop Vortexing
- GL 88.017 NRC Concerns and Actions on Loss of RHR
- SOER 88.003 Losses of RHR with reduced water level at PWRs
- FF 88.031 Auto closure initiation change per DCP 87.242
- LER 269.030 De-pressurization of FGDt lead to T.S. entry
- FF 88.017 RHR Vortexing at Mid-Loop 4
LO-LP-12101-20-C REFERENCES :
8.
Instructional Units c.
LICEMSED OPERATOR LO-IU-12101-001 Place RHR in Standby Readiness LO-IU 12101-002 Start Up RRR LO-IU-12101-003 Fill Ptfueling Cavity LO-IU-12101-004 Drain Refueling Cavity LO-In-12101-005 Investigate RHR Alarms b.
NON-LICENSED OPERATOR NL-IU-12101-001 Prepare RER for Operation NL-IU-12101-002 Drain Rafueling Cavity 9.
Transparencies LO-TP-12101-001 Objectives LO-TP-12101-002 RRR System LO-TP-12101-003 RHR System Time to Cooldown LO-TP-12101-004 RER CVCS Interfaces LO-TP-12101-005 RHR Train "A" Cooldown LO-TP-12101-006 RER Pump LO-TP-12101-007 RHR Pump Controle LO-TP-12101-008 RHR Pump Curves LO-TP-12101-009 Control Board Switches LO-TP-12101-010 Control Board Instrumentation LO-TP-12101-011 RHR Heat Exchanger LO-TP-12101-012 8701A/8701B and 8702A/8702D Controls LO-TP-12101-013 R11R Loop Suction Valves LO-TP-12101-014 RHR Pump Mini Flow Valve LO-TP-12101-015a Open RWST Suction Valves LO-TP-12101-015 RHR RWST Suction Valve Logic LO-TP-12101-016 RNR Containment Sump Suction Valves LO-TP-12101-017 Safety Grade S/D RHR Suction Valve Arrangement LO-TP-12101-018 Normal RCS Cooldown LO-TP-12101-019 ' Cold Leg Injection LO-TP-12101-020 Cold Leg Recirc LO-TP-12101-021 Hot Leg Recire LO-TP-12101-022 Solid Plant Pressure Control LO-TP-12101-023 Venting RHR System LO-TV-12101-02 4 RCS Elevations LO-TP-12101-025 Tygon Turs Level Indicators LO-TP-12101-026 Temporary Level Indicators LO-TP-12101-027 RCS Levels Vs Indicators LO-TP-12101-028 RHR Heatup Rate LO-TP-12101-029 Time to Boiling LO-TP-12101-030 Time to Core Uncovery i
5
LO-LP-12101-20-C REFERENCES :
10.
Student Handouts LO-HO-12101-001 Objectivee Page 2-10 Interlo,cks, Logica LO-HO-12101-c-002 Loss of Faut 11.
Video Tape Mid-loop RHR Vorteming 12.
Appendix A Westnghouse owners Group Narrative for Mid-loop Training Video Tape 13.
Standing night order 2-86-22 "RCS Level Monitoring" s
6
.m LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES I.
INTRODUCTION A.
When plant shutdown is required for refueling or mainte' nance, cooldown of plant is required.
1.
Cooldown is accomplished by dumping steam to main condenser, This methog will only allow cooldown to a.
around 212 F (steam formation at atmospheric. pressure).
b.
This method is slow when approaching low steam pressures.
2.
Cooldown is accomplished using RHR' system after main steam cooldown has reduced plant temperaturn to within RHR capacity.
a.
RER coolgown can take the plant to less than 140 b.
RHR used to maintain RCS temperature at low valves for long periods of time.
- 1) Removes fission product decay heat.
B.
Under accident conditions the RNR System serves as part of the Emergency Core Cooling System.
1.
Automatically rtarts to provide high volume borated water to the RCS.
C.
The RHR System is an important system used for routine plant cooldown and for emergency core cooling.
D.
Prevent Lesson Objectives LO-TP-12101-001 II.
PRESENTATION A.
Purpose / Functions 1.
To transfer heat from the RCS to the Component LO-1 Cooling Water System (CCW) in order to reduce NL-1.(A) the temperature of the reactor coolant to cold shutdown temperature (140 F).
2.
To serve as part of the ECCS during the low-pressure injection and recirculation phases following a LOCA.
3.
To transfer refueling water between the RWST and the reactor cavity before and after refueling.
7 l
. -..~
-... -..~...
LO-LP-12101-20-c
_E LESSON OUTLINE:
NOTES B.
System Layout LO-TP-12101-002 1.
Show the RNR System pointing out each item LO-2 s
which the student must be able to include in NL-2 (A) a one-line drawing of the system.
a.
Include the following:
Valve numbers are not required
- 1) Temperature enntrol valves (606 and 607)
- 2) Pump inlet isolation valves (8701 A/B and 8702 A/3) 3)
Pump miniflow control valves (610 and 611) 4)
Pump suction valves (8812 A/B and 8811 A/B)
- 5) Hot leg crossover isolation valves
-(d716 A/B)
- 6) _ Recirculation valves (8804 A/B)
- 7) Cold leg injection valve (8809 A/B)
- 8) RHR bypass valves (618 and 619)
- 9) RHR pumps
- 10) RNR HX 11)
Interfaces a)- RWST b) RCS c) cycs
~
d) 313 e). PRT f)- RHR HX/CCW g).BRS HUT c.
Design-~
1.
The RHR is placed in service approximately 4 8
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LO-LP-12101-20-C III.
LESSON OUTLINES.
NOTES hours after shutdown (with RCS at 340 F and 365 peig).
2.
Both Trains of RHR in service (5000 gpm CCW LE-TP-1'2101-003 flow at 10$oF, each train).
0 a.
Should reduce RCS temperature to 200 F in 0
3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> 140 F in 17 more hours.
0 b.
30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> to 200 F with only one train RHR.
3.
RHR System Operating Design LO-3 a.
Temperature 400 F b.
Pressure 600 peig D.
System Description
1.
Removes heat generated by a.-
Radioactive decay of fission fragments b.
Reactor coolant pumps 2.
Can divert a portion of the RHP. flow to the LO-TP-12101-004~
CVCS letdown line.
(color coded) a.
Allows checistry Control and sufficient letdown at low pressure.
b.-
Allows pressure control if solid.
3.
Two independent flow trains are provided LO-TP-12101-005 (Train A and B), each of which is espable of satisfying all requirements.
4.
Cooldown rate is varied by_ changing flow through the heat exchangers.
5.
Major components and controls
-a.
RHR pumpe LO-TP-12101-006
- 1) One pump in each train
- 2) Single stage, centrifugal 3) 400 horsepower a) 600 psig design discharge NL-3 (A) pressure
)
1
LO-LP-12101-20-C III.
LESSON OUTLINE NOTES
- 4) Starting limitations LO-4 a) Three consecutive starts from ambient temperature b)
Two starts from operating temperature c)
S9bsequent start permitted af ter 15 minutes if the motor is left running or 45 minutes if motor is left at standstill.
- Nscw a)
Pump 1A from 1AA02 NL-4a (A) b)
Pump 1B from IBA03
- 6) Require 14 feet of NFSH (should be LO-TP-12101-007 at least 20 available)
- 7) Design head is 375 feet TDH NL-3 (A)
- 450 ft (Differ-ence due to EOP considering system suction
- 9) Runout is 4500 gpm at 325 feet head) 10)
Miniflow line opene to maintain at Opening setpoint least 700 gpm flow and shuts when designed to pro-flow exceeds 1400 gpm.
vide between 530-654 gpm rectre a) Removes pump heat
" HOT", 500-617 gpm recirc " COLD" b) Prevents cavitation during low-flow conditions 11)
Control of RHR pump LO-TP-12101-007 a) Handswitch (main control board)
LO-TP-12101-008 and PSDA/PSDB (1)
Start LO-TP-12101-009 (2) Auto -- will start on LO-6 sequencec on an SI signal 10 1
.~
LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES-
.s
~
(3) Off LO-TP-12101-010 (4)
Pull to lock of f can also be started and stopped from its respective shutdown panel.
b.
RHR Heat Exchangern 1)
Single pass, U-tube and shell type LO-TP-12101-011 2)
Tubes are made of austenite stainless steel 3)
Shell is made of carbon steel 4)
Capacity = 32.8 x 10 BTU /hr c.
RCS Suction Valves-LO-8a 1) 8701A/8701B and 8702A/87025 (QMcB-A, LO-TP-12101-011 PSDA, PSDB)
LO-TP-12101-012 LO-TP-12101-013 2)
Motor operated 3)
Power supplies NL-4b (A) a) '8701A - MCCIABE Safety Grade S/D b) 8702A - INV. 1DDI16 c) 87018 - INV. ICDI15 d)- 8702B - NCC1BBE-4)
Three position handswitchee
~
a) Open-spring return to AU70 b) - Auto
-c)
Close-spring. return to AUTO 5)
-Control roon handewitch can only open-the valve if a) RCS EVLIS pressure is less than-4 transmitters, 365 psig, and one for each valve, off pts on RVLIS taps Surveillance 11 1 :-
,, -. ~ ~. -,. -
-. - ~. ~., ~. - _.. _ ~. -.... -.-. - _.-... ~.-
LO-LP-12101-20 C:
III..
LESSON OUTLINE:
NOTES i
test verifies b) That train's RWST suction valve LO-8s cont.
is shut (8812A, B) and
~
c) ECCsrecirculationvalvehorthat train is shut (8804A/88048)
TR AtCCP, TR Bt-SIP, and d) Containment sump isolation valve for that train is shut (8811A/
1 88118) 6)
suction valves will auto shut on RCs high pressure of 750 peig a)'~RCS RVLIS pressure transmitter failure high.
7)
Valve control can also be from their respective shutdown panel-a) Transfer switch on the shutdown panels (1) Transfers control to-shutdowr. panel
-(2)
De-energizes valve. position lights on Main Cortrol Board-
'(3)
Sounds,an annunciator on Main Control Board (4) Disables the opening inter-locks (S) -Disables the auto shut feature on hi pressure d.
suction Relief valves (8708A/87083) 1)
protect the RHR system from LO-7 overpressurization NL-5.(A) 2)
design prwesure of RHR much
_less.than RCS' 3)
Setpoint = 450 peig 4)
Relief flow capagity = 475 gym at 450-poig and 375 F each-12 I
l
LO-LP-12101-20 C 111.
Lt.% SON OUTL1HEs NOTES 5)
Water re11taved goes to the PRT (because inside RC) e.
suction line vent valves (IIV-10466,
-10165) 1)
To provide a moans of venting air Air pockets can entrapped in suction lines cause RHR puttp to becomo air bound L ~
2) stolenoid operated 3)
Remote position indication 4)
Controlled by handowitch (HS-10466,
-10465) on the QHCB 5)
Used ducing fill and vent procedure or as necessary if air binding of PJtR pump is indicated p
f.
Discharge relief valves (8856A/8856B and Lo-7 8842)
NLe5 (A)
~
y 1)
To prevent overpressuriaation of the RHR system due to maximum possible backloakage espected frce the RCs cold lege 2) 54tpoint a 600 poig 3)
Relief flow capacity = 20 95xn at 600 peig 4)
Water relievad goes to 1 HUT (because outside HC) i g.
Heat exchtnger outlet val' v NL-6 (A)
{
11 606 and 607 (QHcn, Ps.t RU 2)
Pneumatic operated (I/F, e)
Faile olen on loss of air or electrical signal
)
3)
Controlled by pushbutton Hagan controller a) Open-close pusAbuttons b) 0-100% volve indication v
s 13 i
4
_. -.. ~. -, - - -...
. _. ~. ~ -...
i I
Lo-LP-12101-20-c
~
112.
tzsson ouTtix :
~~
norme
- 4) Valve operation a) 100% demand signal moves valve 604 open i
(1) Valve travel limited to prevent pump ru< rut l
(2) Downstream flow orifices PO-10961; 10962; also prohibited pump runout 10963s 10964 l
b) Unit 1 tiow orifices are sized Wrong (too hig) l I
(1) Valve stroke reduced to 50%
to $5% open t
c) Unit 2 flow orifices are sited cortectly (1) Valves ntroke full travel i
1.e.,
60% open 33,73 l
5).
Valve position - manually set to
. control cooldown rate (works in conjunction with bypass, i.e.,
- bypass modulates open or closed to maintain constaat flow) 4)
Valva control also from respective
-SDP a) Transfer switch on 3DPs (1) Transfers control to SDPs a-(2)
Sounds annunciator on main control board h.
Plow control valve LO-8b 1) 414 and 619 (GMC8, PSDA, PSDB) 2)
Pneumatic operated (!/P) i Loss of air also e) Palle shut on loss of air or to 606/607' electrical power results in max cooldown rate 3)
Controlled by pushbutton Hagan controller-a).open/close.pushbuttons 14
__.._-.a_,__..._,___,_.u_.,a._.
.. m-...
1,0-1.P-12101 - 2 0
- C
!!!. LESSON OUTLINE 8 NOTE &
b) Auto / manual pushbutton c) 0-1006 valve position indication 7
d) 10 turn potentiometer - utad to set in total flow 4)
Total flow normally set to a minimum 1.0- 8 b of 3000 gpm a) As TCV 606/607 le manually Hx outlet opened / closed for cooldown rate i
b)
FCV 618/619 modulates to maintain Hx bypass flow rate 5)
Valve control also from respective SDP a) Transfer switch (sanc.as TO/s)
- 1.
Mini-flow recirculation valves Lo-pa PF 66.004 1) 610 and 011 (QMcD, PSDA, PSDB).
2)
Motor operated LO-7P-12101-14 3)
Three-position handowitch a) Open/close, spritg-return to AUTO b)- AUTO (1) controlled by flow transmitter at RHR pump.
outlet (2) Opens when flow is reduced NL-7 (A) to 700 gpm i
(t) To remove pump heat-(b)
Prevents cavitation during low-flow conditions (3) Closes when flow exceeds 1400 gpm 4)
Valve control also-from respective sDP 15
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T wv T e-*v+WM' w+ y*y**WWNw wr w-e M yr-4 iH M wwd-+-wm'-Niv*=v-*1+w-t9Nn7 verr-*upy'vDV"7-
+ v T'T'"W 9PM * #'
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LO-LP-12101-20-C 111.
LESSON OUTt1NB NOTES a) Transfer switch on SDPs (1) Transfers control to SDPs (2) Sounds annunciator o'n MCB (3) De-energises valve position ir.dicating lights on MCS j.
RW8'r Suction valves LO-8d 1) 8812 A and 3 (QMCA, PSDA, PSDR)
LO-TP-12101-015 2)
Motor-operated 3)
Three-position handowitch a) Open/close - spring return to normal 4)
Interlocks a) To open 8012A (1) Containment sump suction (8811A) shut and (2) CCP recirculation suction (8804A) must be shut b) To ogen 88128 (1) containment sump suction (88115) shut and (2) SIP suction (98045) shut 5)
Valve control also from respective e
-8DP a) Transfer. switch on SDPs (1) Transfers control to SDPs (2) sounds annunciator on MCs (3)
De-energizes valve position indicating lights on MCB (4)
Disables the oper.ing interlocks 16 A
i...,,..-.,i.i.,-...n..a
LO LP-12101-20-C III.
LESSON OUTLINE:
NOTES k.
Containment Sump Suction Valves LO-8e LO-TP-12101-016 1) 8811A and 3 (Omen only) 2)
Motor-operated 3)
Three-position handewitch a) open/close/ spring return _to auto b) Auto (1) Auto opens on UI signal and RWST low / low level 4)
Interlocks a) To open 8811A manually must have (1) At least one loop suction closed (8701A or 8) and (2) RWST suction 0812A closed b) To open 88113 (same except specified valves for Train B) 1.
Instrumentation LO-TP-12101-01$
1)
Recorders a) RWST level b) Containment sump level j
c) MX inlet / outlet toeperatures 2)
Meters a) RHR pump discharge pressure b) RHR pump discharge flow
- 3) Alarme a) RHR pump overload trip b) RHR pump i high discharge pressure c) RHR pump 2 high discharge pressure 17 l
~_._.__.________.__._.___,_____m___.___._,_.
i l
LO-LP-12101-20-C
!!1.
LESSON OUTLINE:
NOTES
..u-m.
Safety crade Cold shutdown RHR Functions LO-7P.12101-017 1)
Following reduction of RCS LQ-9 temperatgre and pressure to less than 340 F and 365 peig, one kHR AoV's in MIR will loop is placed in service using Est.
fail to maximum powered loop isolation valves.
'!CV cooldown; there-and FCV in loop have failed thus fore must have placing all flow through RHR heat alternate means i
exchanger.
RHR loop cross-connect of controlling valves are closed to reduce flow cooldown rates AOP-1802$
2)
NOTES Loop isolation valves, P701A 87014-Hec 1ADE i
and B and 8702A and R have separate 8702A-INV. 1DD116 power supplies to support 87018e!NV. 1CD115 I
requirements for safety grade cold 8702n-Hec lost I
shutdown
- 3) Allows isolation capability on loss of all Ac n.
Control board lockout switchee remove Lo-10 control power, usually 120 VAC, from the switch contacts on the bench board switch (HV-6809A/8 & HV-8840)
- 1) Ensures no inadvertent valve lineups can occur that will defeat an ECCS injectic,n flowpath
- 2) Requires direct operator intervention to perform switchover from cold to hot log recirculation E.
system Interface 1.
RHRS interfaces with the followings a.
RCS LO-11a NL-10a (A)
- 1) Not and cold leg injection for ECCS 2)
Loop 1 & 4 for normal cooldown suction returning via cold lege b.
RWST - supply of t, orated water during LO-11b ECCS NL-10b (A) c.
Containment - sump collects borated water LO-lle e
for recirculation phase NL-10c (A) 0 18
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...,_.__m
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- ~ _ _..,,,,.,_
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LO-LP-12101-20-C Ill.
LESSON OUTLINE NOTES d.
CVCS LO-11d NL-10d (A) 1)- RMA cleanup 2)
Pressure control
- 3) RCS seal injection e.
Safety injection-- same lines as RHR5 for LO*11e ESF injection phase NL-10e (A) f.
PRT - collects discharge from suction LO-ilt reliefs for maximum credible overpressure 1:L-10f (A) transient (PRT used because relief is in containment) i g.
BR5 HUT - collects discharge fran LO-11g discharge reliefs from RC$ btekloakage NL-10g (A)
(BR5 HUT used because relief is outside containment) i h.
CCW - supplies RHR heat exchangers and LO-11h pump seal coolers NL-10h (A) l 1.
NSCW - supplies RHR pump motor coolers LO-111 NL-101 (A) i F.
System Flow Pathe 1.
Overview a.
Normal cooldown flow path LO-124 HL-8a (A)
- 1) Flow from RCD 1 & 4 L-21 Thru RER suction valves LO-TP-12101-018
- 3) AMR pumps in operation providing-flow
- 4) Flow passes thru RHM heat exchangers for cooling
- 5) Cleat exchanger outlet valves throttled to maintain cooldown rate
- 6) Reat exchanger bypass valves automatically maintain system flow
. rate
- 7) RMR pump miniflow recirc automatically maintains mini flow to RHR pump 19 u.-.
.__. _ _ _ ~. _ _.. _ _
.m
.._m, t
i LO LP-12101-20-C 211.
!OSSON OUTLINRs NOTES
(
8)
Flow returns to RCS cold lege (1 & 2 f
Trn A and 3 & 4 Trn B) b.
Emergency Core Cooling Injection Flowpath LO-TP-12101-Ok9 LO-12b 1)
RHR pumps start automatically NL-8d (A) 2)
RWST is source of 2000 ppe borated water 3)
Pump suction valves from RWST (8812A/
88128) are open
' i
- 4) Other suction valves are shut i
- 5) Heat exchanger 6)
To cold legs (via 8009 A/5)
- 7) Won't inject flow into the reactor until reactor pressure drope to about 300 peig (20P's)
(450 ft. of head)
Cold Leg Mecirculation Phase Flowpath LO-TP-12101-020 c.
LC-12c
2)
RWST level drops
-3)
The water flows.into the RCS and over the core and then out the creak 1
ending up in the containment sump 4)
Level in RWST reaches the low-low level setpoint, then 5)
Suction valves.from containment sump auto open 6)
The operator should then manually shut RWST suctions (8012A/88128) 7)
8804A & a opened to provide suction to CCPs and SIPS
- 6) '8716A & B shut by operator LO-TP-121,01-021 d.
Hot Log Racirculation Phase Flowpath LO-12d NL-80 (A).
3 1)
Purpose Oissolve boric acid Crystals can' form-l s
20 i
l l
m-m I
LO-LP-12101-20-C ZZZ.
LFSSON OUTL1NSI NOTES
' crystals formed on upper Rx vessel upper regions of internals during cold leg core if voiding recirculation is significant a)
For reactivity control b)
Prevent degradation of heat transfer coefficient of upper region of core 3
2)
Following large LOCA, cold leg recire,, RWST LO-LO level, transfer from cold leg recire. to hot leg recirculation after IVENT initiation (Commence at 15 hes per E0P) a)
11 hours1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> on U-1 b) 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> on U-2
- 3) Align MHR system for hot leg recirculation a) Close RHR cold leg injection isolation valves KV-0009A/B b) Open RHR pump discharJe cross-connect valves HV-8716A/B c) Open RHR hot leg injection isolatson valve NV-8840 4)
Flowpath of hot leg recirculation LO-12d a) RHR Train "A* -.CTNT sump, to RRR RHR, SI pump to pump, to RHR HK, to RCS hot legs hot Legs, CCP to 1 & 4 and CVCS charging pump Cold Legs suction header, to cold lege 1, 2, 3,_and 4 b) RNR Train *B" - CTNT sump, to RNR pump, to RHR HX, to RCS hot legs s
1 & 4 and safety injection pump suction, to hot lege 1, 2, 3, and 4
G.
System Operations 1.
Guided by SCP 13011-1 and UOP 12006~1 LO-TP-12101-003 2.
RCS cooldown to 375 F LO-13a a.
Reduce number of RCPs running l
21 l
l_,._
___..._._._.___._.m_____.___
i LO-LP-12101-20-c IIh.
LEssoM OUTLINR NOTES i
b.
Start pressuriser cooldown and depressur-isation c.
ArW to 80s d.
ARM cops 3.
Start RHR (one train)
Nornial cooldown Sect. 4.2 l
a.
Restore power to loop inlet teolation valves
+
b.
Align one train for minLmum flow
- 1) close the following i
a) Hot leg crossover isolation LO-TP-12101-022 (HV-8716A or 3) j b)
RNA HX outlet valve (HV-606 or 607) c)
RNR HX bypass (TV-618 or 619),
put in manual d)
RW87 to RNR suction (HV-8812A or a) 2)
Perform the following a) Open loop inlet valves (RV-8801A and 3 or 8702A and 8) b) Remove power from 8804A and 88043 (1) Prevents overpressure condition of 81 or Charging system low pressure portion of system (pump suction piping)
(2) Prevents inadvertent operation of 8804A/88045 in 3
case of a cable tray fire (3) 8812A/B, 8920, and 87025 can only be operated from 80 panel due to. interlock power with 8804 valves c) Open miniflow isolation (rV-610 or 611) 22
__,_., _.._...,._.._ _.._,_ _ _.,_.._.~. _ - _ _
LO-LP-12101-20-c 111.. LESSON OUTLINES NOTES 3) 6 tart ML1 pump i
f
- 4) Warm up syntes as follows:
a)
Establish RHR letdown - emell portion of RHR is flowing from Res to CVCS allowing slow heatup
[
b)
Monitor temps c) When system le warm establish full flow 4.
solid Plant ope (12006-c Procedure)
{
a.
Res temp 120 F - 180 F
- 1) Maintain Res pressure
- 250 peig 2)
Place all L/D orifices in service 3)
Increase charging flow or lower RHR LD flow 4)
Indicated by I
a)
Increase in Rcs pressure b)
Rise in letdown flow 5)
Prosauro controlled by relative difference between letdown and charging P!c-131 now means of pressure control 5.
Shifting RNR Traine 13011-1 i
Section 4.4.
a.
Start up idle train on minimum flow
- 1) Align flowpath 2) start pamp b.
shift RHR letdown to train with minimum flow c.
Det chosistry and boron within space d.
shift from one train-to the other
- 1) Maintain total flow 3000-3500 gpa k
23 4-c
..,-.n.--,.
.,...n,,,,,,--.,-,,,,.
,,.n...,
.--.,-,,,..,-,,,,,._n,,
.,~e,,-
,+-,,m,,,
,-,e
- r~.,
s.
m _ _ -. _ _ _. _ _. _ _ _ _.. _ _ -.. _ _
t I
LO-LP-12101-20-C i
121. LtsSON OUTLINE HOTES L
i 1
- 2) Throttle HX outlet and bypass closed on outgoing train and open on incoming train i
3)
Cool ogtgoing train (miniflow'racirc) i to 200 F and stop pump 4)
Establish cooldown rate on running train 6.
Removing RMR frue service / Place in Standby I
LO-11 a.
Fill and vent if following maintenance 12001-C (Section 4.5) 13011-1 b.
If in properation for plant start up, section 4.1 o
cooldown to below 200 F t
Pun through miniflow until below 200*F c.
Trip pump, return to AUTO d.
Align for standby 1)
Flowpath established for 81; RWST to Checklist 2 Pum through HK to RCS cold leg
- 2) MX bypass in manual and clnsed
- 3) Loop inlet isolation closed, sump-inlet isolation closed, RHR to CCP and s!P suction closed 4)_ Parallel hot leg crossover inciations open (KV-8716A and B) and single hot log crossover isolution (HV-8840) t closed 5)
Power lockouts for cold leg discharge Lockouts ensure and hot leg dischargs_ valves 'off" direct operator _
(8809C & D and 8040A) intervention to switch from cold log to hot leg recite 7.
If RMR requires depressurisation it can be LO-TP-27101-023 i
vented via check valve teet lines 8.
Refueling ops (Filling RCS and Refueling 12007-C
.\\
24 I
u
.y..
y~
_m.,~
_,_,-o~m_,..., -.,....,_,_,,,.,,.., _,,..,., _,
,,_mm._,,,.,.._,w_,..
.,_....,-.,,__,.,_c..-..,
_ _. _ _ _ _. -.. _ _ _ _. _. _ _ _ _. _. ~. _ _ _ _. _. _ _..
s i
14-LP-12101-20-0 111.
Lrssom outLINs NOTES Cavity)
~
13011-1 i
a.
getablish applicable refueling cavity Section,4.6 l
monitoring NL-Ob b.
I6clate the following:
1)
RHR to cold leg i
2)
Mt bypase 3)
HX outlet 4) toop inlet c.
Open suction from RW87 and verify pump l
niiniflow ope t d.
OMn RHR to cold leg valve e.
May either gravity feed or use punp f.
Start RHR pump Section-4.3 Normal cooldown g.
Establish RHH letdown 1)
Close RMR let(.swn isolation valve Section 4.3 (HV-128) t
Prevents pressurising suction of idle R4R purp
- 3) 31DWLY open MV-128
- 4) Adjust ?V-131 h.
Verify chemistry and boron specifications are mot, or cleanup using letdown mixed bede until specs are met 1.
Warie-up RMR to within 25 F of RCS (or as otherwise epocified Ly 85)
- 1) Open RNA to cold leg isolation (NV-8009 A or 8) and slowly throttle open RNA HX bypass (PT-618 or 619) to obtain 500-1000 gren; adjust PV-131 as required 0>
1 i
,,.-,-m,
-,,.s,
, -.... ~,.. _, - - - - -,. -. _, _. -,.., - -, _
,_-._,-.-_-...,,,-----_-.-,w-..-
,......_,...-,..-,._.-m._..m---
4-,...
.___._.m..__.~.~m.
i LO-LP*12101-20-C l
111.
LES$0M OUTLIMla
~ NOTES L
a k) Monitor RHR HX inlet and Ph RCS Rhot j.
Initiate full RRR flow to RCS
[
l
- 1) Open HX bypass valve (TV-616 br 619) to establish at least 3000 gpm and place &n AUTO i
- 2) Verify minillow isolation valve closse
- 3) Adjust PV-131 in cycs i
k.
Cooldown rate will be established by slowly opening HK outlet valves.
(As coolant temperature decreases, these valvee will have to be opened further to maintain same rate. )
1.
If desired, pressuriter bubble is collapsed i
12006-1
- 1) Lower letdown
- 2) Maintain auxiliary spray i
m.
Throttle open HX uutlet to control flow i
n.
When full. clooe open valves (stop pump, if used) o.
Realign by opening loop inlet isolation and cold leg injection pathe 9.
Draining the refueling cavity 12000-C a.
setablish cavity monitoring 13011-1 Section 4.7 b.
Flovpath NL-Sc (A)
- 1) close CL injection valve, hot leg isolation for other trein, common hot leg crossover injection isolation valve, arid PwsT suction 2)
RX bypass in manual and closed.and MX outlet closed
- 4) Open loop inlet isolation and verify
-miniflow isolation open
- 5) open hot leg crossover isolation for i
applicable train 26 9 wet-e erweire-et-q n se =a
,s e c 5 gy e,,aw--et---n--m-+-...,-!.
,,wce.-
-,-.-r.n-,,
,.,e,y-3.c,me--,,--,twr.e-e-y,ww.-,--r,.w v=-,,,
--r,.iy---w
-, w-w w
.,et_--g
,e y a y
. - -. - - ~ - ~ -...... -..-,. -
-.., -. ~. - _ - -..,
i LO-LP-12101-20-C 111.
LESSON OU7t!NE's NOTES 4
c.
Start RHR pump d.
Slowly open HX outlet to desired flow Starts SOEA 88.003 9
a)
Encessive flowrate during pumpdown with Vpper Internale Assembly installed could lead to void formation in RHR pump suction
- 2) NOTE:
a) With the water level in the Refueling Cavity less than 217 feet 0 inches elevation (23 feet above the vessel flange),
both trains of the RHRS are required to be operable with one train operating
- 3) Control of Drsining Evolution a) Operation at reduced vessel water levele requires continuous.
operator attention b)
RHR system probleme must receive timely response c) Refer to 18019 and dieeuse (1) rigure 2 -- Time to Boiling (2)
Figure 3 -- Time for Core Uncovery (3)
Figure 4 ~~ Heatup Rate-d) operatore must be knowledgeable of all activities that could reduce RCs inventory e)
If level detection syntam is loss or accuracy becomes suspect (1) stop intentional draining e.
When gomplete, cloas HX to outlet, stop pump, open RHR cold leg injection and close and cock RHR return to RWST 27 f
J
+
~ ~ -.
,..-r..,,,w,,,,,,,+
q.,,,--+
y
..,w..
..r,..~..,_.g.
.y.,y,--._,,.w.._,,.,.r.,,ym,
,,,_,,e...,.9,_,.p,m.%,,
9.y,,,.w.,w-.,,w,
. _. - ~
LO-LP-12101-20-C
^
111.
LESSON OiJTLINRt NOTES 10.
Preventing Water Hamroer in RHR System Start NUREG 0927 (water hammer) a.
Water hat.ener can occur in any system under certas.. conditions b.
Can result in severs damage to piping and components c.
Primary cause of water haasner in PVR RHR systems is voiding d.
Operator should koop the possibility of water hanseer in mind when operating this system
- 1) Proper filling tend vanting of lines and components 2)
Check for possible back leakage of water / through check valves from P;CS (chacking temperature in lines, pressure relief valve operation)
- 3) AvoiG rapid valve motion stop NUREO 0927
?
H.
Precautions and LLaitations 1.
Precautions SOP 13011-1 a.
Do not throttle tooling water flow to RHR HX (to prevent overheating CCW) b.
Initiate flow through system slowly - to LO-15a avoid thermal shock
-RC8 pressure not to exceed 425,psig.
LO-15b c.
Temperature not to exceed 350 P d.
RER limited to single train operation LO-15e whenever RC8 is at mid-nozzle level (187
- 0* elevation) to prevent pctantial LO-16 suction due to gas entrainment from vortex formation. This could cause a loss of RHR due to gas binding.
2.
Limitatione a.
Tech. Spec, operability requirements for different modes 28 i
4 I
,,...m.__
--.,,,_.,___.-,.,...m,
....m.r.
m r.
.-....,,.___.,,.,4.
1 LO-LP-12101-20-c III.
LESSON OUTLINE:
340TES b.
Inlet isolation valve interlocks c.
RHR puop motor allowed one restart if allowed to coast to a rest between starts I.
Technical Specifications 1.
T.S. 3.4.1.3 (RCS/ hot shutdown)
LO-17 Cover LCo. one 2.
T.S. 3.4.1 4.1 (RCS/ cold shutdown - loops hour action filled) statements and applicability 3.
T.S. 3.4.1.4.2 (RCS/ cold shutdown - loops (snos cover eot filled) bases) 4.
T.S.
3.4.9.3 (RCS/ COPS) 5.
T.S. 3.5.2 (ECCS Tavg 2 350 F) 6.
T.S. 3.5.3 (ECCS Tavg < 3$0 F) 7.
T.S. 3.9.8.1 (RF high water level) 8.
T.S. 3.9.8.2 (RF low water level)
J.
System Operating History Start SER 84.079 SOER B$.004 1.
Events involving loss or degradation of RRR SER 86.035 caparility have occurred frequently throughout IEN 86.101 the industry over the last several years.
OE 1861 NED 00.012 a.
Have not resulted in major consequences, although it has resulted in boiling in some cores.
b.
Does have potential for major core damage
- 1) Coolant boiling may occur with long term risk of inadequate core cooling
- 2) Greatest potential when decay heat loads are high just after reactor shutdown
- 3) Loss of RHR while reactor vessel is partially drained has blaher potential for core un y and release of airborne ra-tweetivity, loss of core shielding, equipment damage and degradation of kCS temperature monitoring 29
LO-LP-12101-20-C III.
LESSON OUTLINR4 NOTES NOTES Point out to students that Stress may be working as shift Supervisors that refresher t-aining on special problems e
associated with placing the eenetor in a partially drained condition should be held prior to draining vessel. This is required per OL 80.017 LO-TP-12101-024 2.
Causes for loss of RHR capability LO-18 a.
Loss cf pueps due to air entrainment Root cause was loss of vessel
- 1) This problem has occurred at several level when RCS facilities due to faulty level is not filled indication and/or vortexing.
2)
In most cases, local level indicators NL-11 (A) utilising tygon tubing were being view Westinghouse used, often without any backup video of RHR indication available-vortexing at mid-loop i
a). Problems that have occurred root valves obetructed by debrio, lack of monitoring, tube construction b) Other special precautions should be taken when relying on use of tygon tubing for temporary level indication 4
c) Pressure vessel and referenen leg must have the saue overpressure i
in order to be accurate d) The system should be static
.(indication lag while draining) e) Temperature of fluid in the RCS I
and the tube should be roughly equal
- 3) At isrge flow rates (for example, when both RHR pumps are in service),
vorteming may occur at suction connection a) Vortexing can result in air Upon indication entrainment in water flowing to of air binding pump leading to air binding of enter AOP for 30 t
LO-LP-12101-20-c III.
LESSON OUTLINE NOTES the pump loss of RHR (restore level, vent auction utility valves HV-10465, -66>
b) Reference legs located on loops where RHR suction is taken are more likely to detect localised level fluctuations due to vortexing c)
Inaccurate or erratic level indication can make vortexing more likely d) Operator should understand correlation between flowrate (number of operating pumps and/or throttle valvo position) and water level as they relate to 4rtexing and air entrainment b.
Loss of RHA pumpa due to other causes LO-18 (cont)
Exneples evereurrent Trip c.
RHR loss due to unexpected closure of RRR suction vaiva 1)
Surre111ance Testing Lo-Ho-12101-c-001 a)
Procedure problems b)
Personnel error
- 2) Clocure due to high pressure interlock 3)
If valter go closed they must be reopened from SD panels due to 8804 valves owing tagged out d.
RER pump cavitation 1)
Indications a) Discharge flow - NOT normal for RCS pressure b) Discharge pressure le UNSTABLE
- 2) Corrective Actions 31
LO-LP-12101-20-c III.
LESSON OUTLINE:
Notts a) AOP 18019 Loss of RHR (1)
If running puep is cavitating, then stop the affected RHR puep(e)*
(2) Realign misaligned valves.
.(3) Vent affected pumps using HV-10466 (Train A) or HV-10466 (Train B)
(4) Continue with AOP etops as specified to return RNR to service or complete alternate actione se specified in procedure Starts NOP.464 3.
-Industry Evente Refer to LO-Ho-12101 for industry evente a.
Waterford 3 -- lose due to stone binding of shutdown cooling puep (SER 86.035) 1)
Event description a) RC5 drained for replacement of MCP esal b) Two drain path used; only one wee secured to stop drainage of Rcs c)
'.*his, in combination with f aulty I
level indication, resulted in escensive draining d)
Pump cavitated; shutdown cooling could not be restored due to air and etene binding e)
Boiling in core resulted; core remained covered 2)
Significance a)- Pailure of temporary level indication led to an extended lose of shutdown cooling and boiling in core b) Dependent upon operator action 32
bO-LP-13101-20ac 111.
LES$0M OUTLINRI HOTES to restore shutdown cooling or provide alternate means of cooling j
c) Worst case conditions (high decay heat rate and partially drained vessel) may only allow 15 to 30 minutes prior to core uncovery d) Monitor level closelv and be Stress aware of all drain paths in operation b.
Loss due to vortexing Start 1E:186.101 FF 88.017 1) show video tape on vortaxing 2)
San onotre 2-a) operators relied on inaccurate level indications and reduced Res level excessively b) Vorteming occurred, air bound Pump c)
Second pump started Lueediately Stress why this.
and also became air bound happened d) Local boiling occurred in core e) Steam and 2 curies of radio-nuclides releanad to containment
- 3) sequoyah 1 a)
RNR pump B being used for decay heat removal with partially drained vessel b) During evolution to switch to TR A, pump A was started before pump a secured c)
High flow while both pumpe running initiated vortaming, eventually both pumpe air bound, and shutdown cooling lost
- 4) catawba 1 a) With one RHR train inonerable,
+
33
__,__.,mm_,
s
. _,, _.., ~.
mm
LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES vessel level was lowered (T.S.
required both trains operable) b) Vortexing occurred, led to air binding c) No shutdown cooling available End IEN 86.101 for 81 minutes c.
Sion 1 a)
Inaccurate level indication resulted in draining RCS level to below RHR suction and RHR was socitred b) Reliable, sensitive and accurate level indication required for level control under these conditions.
If lost, level reduction should be secured until indication is returned 2)
V.C. Summer a) OOPS test resulted in closure of RNR suction isolation b) operators responded quickly to secure pump and then return it to service c) Events involving closure of suction valves have also occurred at Calvert Cliffs, Ginna, and Diablo Canyon 1 3)
Beaver Valley 1 a) Wire lifted prematurely while establishing clearance de-energized bus supplying RNR pump b) DG started and RHR pump was re-started within 2 minutes of trip 4)
D.C. Cook N
34
LO*LP-12101-20-C III.
LESSON OUTLINRt NOTES a) With one RHR pump in service with vessel partially drained, second PHR pump started b) High flow caused vortering, resulting in cavitation and air binding of both pumps d.
Loss of RMR at Davis-Besse 1 -- Its Start IED 80.012 80.012 1)
RHR lose for two and one-half hours while in Mode 6 2)
Many systems out-of-service for maintenance or testing a) Hay have placed too much burden on Supervisors in the control Room to coordinate activities 3) systems deactivated to preclude inadvertent actuation 4)
Initiating event Loss of 13.8 KV non-safeguards bus causing SFAS Logic a)
Details not Laportant
- 5) Hot leg suction to RHR isolated on logic signal 6)
Lesson learned a) Kaintenance and testing during refueling shutdowns must be closely coordinated and a questioning attitude must prevail.
"What if.
b) Strict adherence to procedures is important whilt in all MODES. A slack attitude during
" cold iron" conditions can get operations and the plant in trouble.
End Its 80.012 start IEN 87.023 35
i Lo-LP-12101-20-C III.
LESSON OUTLINES NOTES NUREO 1:69 e.
Loss of RHR at Diablo Canyon (IEN 87.023)
IEN 88.036 1)
Event initiation A plant engineer opened a valve to per-form a local leak rate test creating a leak from the Acs a) Loss of RKR cooling b) RNR pump began cavitating c) Operator shut down the running pump d) Operator started and then shut down the standby pump.
It also cavitated
- 2) RHR cooling capability lost a) No method of monitoring incore temperatures b) Validity of the temporary RV level indication suspected c) operator dispatched to check local RV tygon tube indication d) operator attempted to verify RCS integrity e), operators attempted to stop leak f) NOUR declared g) Leak stoppai after approx. 1.5 hre 1.w.., by engineer q T_' y I )y operators refilled the system from d
,y the RWST via a RER pump 2)-
Fundamental causes and discussion topice a).RV level indication system problems b)
Improperly seated salve c) operator awareness of evolutions 36
,, -. _ _ _. ~. _. -
., _ _. - - ~ _... -, _. -. _. - -..,.. _ _ -.
i l
I LO-LP-12101-20-c 311.
LESSON OUTLINE:
NOTES l
in progress d)
Containment integrity probleme e) Mid-loop operation f)
Instrumentation
)
g)
Communicatione probleme h)
Event wisclassification 3)
Post-event Technical and administrative
)
investigative actions taken at Plant Vogtle a) several procedure related defici-encies were identified and corrected End IEN 87.023 NUAEG 1269 f.
CL-88.01 Loos of Decay Heat Removal Significant new information has been gener-ated since the Diablo canyon event April 10, 1987
- 1) several previously unrecognised phenom-ena need to be addressed.
a) some of these realistically can cause core uncovery or complete core voiding in less than half an hour.
(Previously believed that 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> would be required.)
b) New phenomena not previously I
understood (1) Pressurisation eg (a) caused by steen fore-ation in unvented reactor vessel (b)
Inappropriate use of so nostle das can lead to core voiding within 15-20 minutes following lose of RHR (c)
Cold leg opening can allow water to be ejec-37 l
LO-LP-12301-20-c III.
LESSON OUTLINE NOTES 4
ted from vessel follo-wing loss of RHR until sufficient water is lost that steam,is relieved by clearing the crossov$r pipee (d)
Pressure difference with-in RCs may prevent water from reaching the RV (e)
Rapio RCs pressurisation may prevent gravity feed from tanks anticipated to be available (f)
Rapid pressuritation may cause instruments to mal-function or provide mis-leading indications (g)
Rapid pressurisation may cause the Ecs to respond in unanticipated ways (h) small Ecs openings (vents and draine) may lead to instrument malfunctions or unanticipated RCs responses (1)
Large RCA pressure bound-ary openings (Se aanway, RCP seals, pressuriser manways) may lead to in-ntrument malfunction or unanticipated RCs responses
- .* ca w (j) 80 secondary side inven-
'etV tory and opening may in fluence RCs behavior s.
(2) Vortexing (a) small amount of air into RHR pump suction may lead to subtle changes that occur over a time of min-utes to an hour or more (b)
Large amounts of air may 38 I
4
LO LP-12101-20-C III.
Lrsson OUTLINE:
HOTES E
cause beeediate loss of RHR (c) Vortaming may occur et levels higher than anticipated (d) Vortexing may not be re-flected by puep current and flow rate instrumente until it is sufficiently severe to cause a lose of RHR (e) Vortexing may cause RCs level indication errors (3) so tube draining (a) Draining $0 U-tube is frequently done by draining the Acs to the point where vortuming could occur (4)
RCS level differences (a) critical level parameter is in hot leg where RHR takes suction (b) Level instrumente con-nected at other points (c) Level difference existe between level indicator and het leg RHR connec-tion point.
(May be sev-eral inches difference)
(5)
RHR system effects (a) shifting from one train to another may cause level changes due to dit-forences in actual sise, etc.
(b) starting one system while another is running can increase total flow thus increase vortexing 39 l
LO-LP-12101-20-c III.
LESSON ~0UTLINE:
NOTES
{
(c)
G, orator response to a l
loss of one RHR pump by starting the second pump may result in the loss of the second pump also if started without cor-recting the cause of the loss of the first pump (d)
Stopping or starting RHR may cause RCS level changes due to partially filled system or air in~
duction into the RNR system (6)
Instrumentation (a) May be in error by half a foot or more without detection of inaccuracies i
(b)
Flow dynamico, entrapped
[
air, and pressurisation may affect level indica-tion, individually or all indicatora simultaneously (c) Many normal instruments disconnected during RV
+
head removal etc.
(d) Romaining instruments may be inadequate End IEN 87.023 NUREQ 1269 IEN 88.036 GL 88.017 g..
LER 289.030 - Depressurising lunt systum Start LER 289.030 leads to Tech spec 3.0.3 entry
- 1) Vogtle Unit 2 3/9/89 a) Just entered Mode 3-e b) Preparations for pressure.
isolation valve leakage test being made c) 38 decides to depressurise RNR system using.RHR test return valves t
40 L
Lo-LP-12101-20-C I.I I.
LESSON Of7LINEt NOTES (1) No approved procedures (2) Valves left open for 14 houre (3) Flow capacity of RHR'was released (4) Leads to inop under (T.F,.)
3.0.3 d) Caubes (1) Attempting an evolution without approved procedere (2) Lack of closed loop communicationv (3) Inadequato systern statuu sensitivity by shift team 4.
Recovery from Loss of RHR U9e AOP 18019-1 for this a.
Refer to-18019 " Loss of RHR*
discussion
- 1) Walk through a Loss of RHR event 5.
Level Indication Problems a.
Many. Industry Loss ct RHR Events have occurred due to level indication problems l
b.
Problems to watch fora
- 1) Colltpse of temporary level indication due to vscuum conditions
- 2) Kinked temporary level hose j'
3)
Improper lineup of level indication eystem END SER 84.079 SCEH 85.004
- 4) Inadequate venting of level indication IEN 86.'101 SER 86.035
Selected Systee Probleme 1.
Loss of air or electrical power to rcV-606 Lo-19a J
(507) or 618 (619) 41 0
1 m
a m_-
___m_
-__.m__-___m.
__.__m-
__u- - - - -
.m_._..
i LO-LP-12101-20-C III.
LESSON OUTLINR4 NOTES
]
a.
Failure mode 1) 606 (607) a) Fails open 2) 618 (619) a) Fails shut b.
System response 1) 606 (607) taLis open - the cooldown may be higher than desired, 618 (619) will respond to the increase flow thru 606 (607) by closing 2) 618 (619) fatis shut - may cause reduction in system flow since 606 (607) are controlled manually from the QMC5. This action may cause the miniflow rectre valves to open to maintain the pump min flow requirements c.
Corrective action 1) 606 (607) fails opent a) manually open heat exchanger bypass. valve 618 (619).to control cooldown b) dispatch operator to determine cause and correct c) shift RHR trains if required 2) 618 (619) fails shuts a) ensure mini flow is operating s
properly b) dispatch operator to determine cause and correct c) shift RHR tr*'ns if necessary
,):
2.
RCS wide range pressure transmitter failure LO-19b high Defeated per UOP 12006 when a.
RHR pump suction valves will auto close on PER Level is <17%
42
LO-LP-12101-20-C
- III.
LESSON OUTLINEl NOTES 4
L indicate high pressure (750 peig) 1)
This will cause suction pressure to decrease with resultant flow reduction through pump
- 2) Miniflow rectre will open to maintain pump minimum flow b.
Corrective action - stop RHR pump 3.
Failure or inaccurate temporary level indication a.
The concern here is not having indication of true reactor vessel level b.
Low levels could result in a loss of RHR pump (s) c.
Corrective action - establish alternate means of verifying level untti temporary level indication is restored d.
Methods of RCS level monitoring.
- 1) cold calibrated PR2R lovs1 (LI-462)
Lo-TP-12101-024 Lo-TP-12101-025
- 2) Tygon hose monitoring
- 3) Temporary level monitor (IC-392) e.
Minimum monitor availability criteria and precautione
- 1) Two of the three level indications should be available when the RCP is depressurized
- 2) When the temporary monitor can be in service its downtime must be minimised %
- 3) Level indications will be disrupted and erroneous indication will occur when draining from loop one-
- 4) Erratic level indication may exist during steam ganurator tube draining.
f.
Special anonitoring requirements
- 1) Continuously monitor tygon hose level 43 t
i 4
y
1
' LO-LP-12101-20-C III.
LISSON OUTLINE:
NOTES indicate high pressure (750 poig)
- 1) This will cause euction pressure to decrease with resultant tiow reduction throuth pump
~ iniflow recire will open to maintain 2)
M pump minimum f,*,ow
- b. _ Corrective action - stop RHR pump 3.
Failure or inaccurate temporary level indication The concern here is not having indication a.
of true reactor vessel level b.
Low levels could result in a loss of RHR pump (s) c.
Corrective action - establish alternate means of verifying level until teroporary level indication is restored d.
Methods of RC3 level monitoring
- 1) cold calibrated PRZR level (LI-462)
LO-TP-12101-024 Lo-TP-12101-015
- 2) Tygon hose monitoring
- 3) Temporary level monitor (IC-392) e.
Minimum moniter availability criteria and precautions
- 1) Two of the three level indicatione should be avs.ilable when the RCS is depressurized
- 2) When the temporary monitor can be in service its downtime must be minimized
- 3) Level indications will be disrupted and
_ erroneous indication will occur when draining f rorn loop one
- 4) Erratic level indication may exist during steam generator tube draining f.
Special monitoring requirements
- 1) Continuous,'.y monitor tygon hose level 43 A
v F'
---__-___x:-
LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES during RCS draining 2)
If control room monitors are not available tygon hose level must be continiously monitored
- 3) When the temporary monitor is in use, every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> the roving watch must call in tygon home level to the control room for comparison with moni-tor level.
Deviations of 2% or more between the tygon hose and monitor truet be investigated
- 4) When level is in region of hot legs trend RHR pump parameters (current) on ERP to detect pump problems due to vortexing 5)
If level becomes suspect, Stop draining and restore RCS lovel g.
Tygon hose installation is performed by the maintenance Dept IAW $4840 " Installation and Removal Instructions For RCS Temporary Level Indication Tygon Tubing" III SUMMAnY
.A.
Review Licensed Operator Objectives
- 1. LIST THE THREE FUNCTION.9 OF THE RHR SYSTEM a.
To transfer beat from the RCS to CCW to reduce RCS temp *5*tur*
- c ld "hutd ""
temperature (140 F) b.
To serve as part of the ECCS during low pressure injection and recirculation-phases c.
To transfer refueling water between RNST and reactor cavity before and after refueling 2.
GIVEN A ONE-LINE DIAGRAM OF THE RHR SYSTEM, IDENTIFY THE MAJOR COMPONENTS AND VALVES.
(INCLUD5 ALL VALVRS AND INSTRUMENTATION THAT INDICATE OR ARE CONTROLLED FROM THE MAIN CONTROL BOARD).
INDICATE VALVE LINEUPS FOR SI INJECTION, SI RECIRCULATION AND REFtTYLING Refer to LO-TP-12101-002 and poAnt out to the students the items required.
44
. ~.
LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES 3.
LIST THE DESIGN TEMPERATURE AND PRESSURE FOR THE RHR SYSTEM.
Temperature 400 F Pressure 600 psig
- 4. LIST THE RHR PUMP MOTOR START LIMITATIONS a.
Three consecutive starts from ambient temperature b.
Two starts from operating temperature c.
Subsequent start permitted after 15 minutes if the motor is left running or 45 minutes if the motor is left at standstill.
- 5. List the power supply for the RHR pumps.(005000K201) a) Pump 1A from 1AA02 b)
Pump 13 from IBA03 6.
STATE ALL AUTO-START SIGNALS FOR TWE RNR PUMPS.
Auto start on SI 7.
DESCRIBE HOW THE RER SYSTEM IS PROTECTED FROM OVERPRESSURIEATION.
INCLUDE SETPOINTS WHERE APPLICAB72.
Suction Relief Valves - 450 peig Diocharge Relief Valves - 600 peig 8.
DESCRISE THE ASSOCIATED LOGIC /OR TKE OPRRATION OF THE FOLLONIleG RER VALVES.
INCLUDE INTEkLOCES AND SETPOINTSa RCD' bion valvoe.
a.
Can open only ifs
- 1) 2:s wide range pressure is <365 psig, and
- 2) that trains RWST suction valve is shut, and
..-_,_m_.
LO-LP-12101-20-C III.
LESSON OUTLINRs NOTES 4
- 4) containment sump isolation valve for that train is shut.
Will auto shut on PCS high pressure of
-750 psig
'u.
heat exchanger outlet and bypass valve <
RHR heat. exchanger bypass valve automatically maintains flow at 3000 gpn
- monitors HX outlet flow
. i RHR heat exchanger outlet valve is manually throttled to maintain cooldown rate (temperature) c.
Miniflow recire controlled by flow transmitter at RHR pump outlet. Opens when flow reduces to 700 gps, closes when flow increases to 1400 gps d.
RWST suction valves Motor operated valves-- to open must have associated train containment sump suction valves shut and associate train suction to CCP/ SIP shut e.
Containoant sump suction valves Mater operated valves -
Auto opens on SI signal and RNST Low / Low level To open manually must have on associated traine, at least one loop suction closed and RMST sucti'on_ closed 9.
DESCRIER HOW THE RHR SYS*lEM MEETS THE w
REQUIREMENTS FOR SAFETY-GRADE COLD SHUTDOWN.
Loop isolation valves have separate power supplies.
10.
STATE THE PURPOSE OF Ri!R/ECCS LOCKOUT SWITCHES ON THE MAIN CONTROL BOARD AND IDENTIFY THE RHR VALVES EQUIPPED WITH LOCKOUTS.
Remove control power from the switch contacta
.46
.y.
g.
5
-am,,
.,,.y.
i
-- ~
- -..,. ~ -
-.. ~..... -. ~..-..-
- LO-LP-13101-20+C t
III.
LESSON OUTLINE
. NOTES on the benchboard for the RRR pump disch header isolation valves for the hot leg and cold ley headers (8809A, 8809B, 8840)
Purpose to ensure no inadvertent valvi lineups can occur that will defeat an ECCS injection 11cwpath. Require direct operator intervention to shift from cold to hot leg recirc.
11.
DESCRIBE HOW THE FOLLOWING SYSTEMS INTERFACE WITH THE RRR SYSTEM.
a.
- Providea hot and cold leg injection for ECCS
- Provides normal cooldown auction from loops 1 & 4 and return path to cold legs b.
RWST Supply of borated water during ECCS.
c.
- Containment Sumps collect borated water for recirculation phase d.
- RHR cleanup
- Pressure esntrol-
- RCP seal injection e.
Safety injection
.Uses same lines as RHR system.for RSF injection' f.
PRT Collects discharge from RHR. pump suction J
relief valvee-g.
BRS. HUT..
Collecta discharge from RHR pump discharge reliefs h.
CCW 47 4
i me Uw--n-
--oe rie-m m
%m, g
g-.
y y
m
-e-.
m.-m -y
m
._~_,..___.___._._..__m.._
..m..
==
LO-LP-12101-20-C III.
LESSON OUTLINES.
NOTES.
Supplies RHR heat exchanger and pump seal coolers 1.
NSCW Supplies RHR pump motor coolers 12.
BRIEFLY DESCRIBE THE FLOW PATH THROUGH THE RHR SYSTEM FOR THE POLLOWINO OPERATIONS:
a.
Normal cooldown Flow from loops 1 & 4, RHR suction valves, RNR pumpe, RHR heat exchanger, heat exchanger outlet valves, some flow thru RHR bypass valve, returns to RCS cold lege 1 & 2 for Trn A; 3 and 4 for Trn a b.
Emergency core cooling injection RWST to RHR pump suction, RHR pump, RHR heat exchanger, to RCS cold lege c.
Recirculatten phase Containment sump, to RHR pump, to RHR HE, to cold lege, and from RHR disch header to CCP Train A to RCS cold legg and from RHR disch header to SIP Trn B.to cold lege 1
d.
Het leg injection Containment sump suction valves to RHR pump, to RHR HX,.to RCS hot lege; and from RNR pump disch header to CCP euction, Trn A and to SIP Trn 8 then-to RCS hot lege Trn A'and 8 13.
DESCRISE THE MAJOR STEPS TO. COMPLETE THE FOLLOWING OPERATIONS:
a.
PLACE RER IN SERVICE FOR COOLDOWN FROM HODE 3-TO MODE 5 d
- Reduce number of RCP's running
- Start.pressuelzer couldown
- Arm COPS
- Aligu RHR train for minimum flow
- Align maniflow valves
- Start RNR pump
[
48 e
i e
e m
e
+ne n
+
~
--m.-
4 g.-
.m LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES b.
REMOVE RHR FROM SERVICE FROM HODE 5 TO MODE 3.
- Close RHR HX outlet valves and bypaso valves
- Run RHR through miniflow ugtil RHR loop cooled down below 200 F
- Trip RHR pump - place in AUTO
- Align RHR for standby operation 4
14.
DESCRIBE HOW RCS PRESSURE IS CONTROLLED DURING SOLID PLANT OPERATION.
RCS and pressurizer full; press controlled by relative difference between letdown and charging 15.
EXPLAIN THE OPERATING PRECAUTIONS AND LIMITATIONS OF THE RHR SYSTEM WHICH RELATE TO THE FOLLOWING:
a.
THERMAL SHOCK OF RCS COMPONENTS Initiate flow through system slowly, b.
PRESSURE AND TEMPERATURE LIMITATIONS ON RHR SYSTEM Pressuro 425 peig o
Temp 350 F c.
LIMITATION ON TRAIN OPERATION WHEN RCS LEVEL IN MID-NOZZLE single train operation 16.
EXPLAIN THE IMPORTANCE OF ACCURATE LOCAL LEVEL INDICATION FOR THE RCS DURING RCS DRAINING operations. Explain the precautions and limitations associated with the concern for accurate level indication Vortexing may occur if level indication is inaccurate (low) and have high RHR pump flow.
Vertexing would cause the RHR pumps to become air bound 17.
FOR EACH OF THE FOLLOWING TECHNICAL SPECIFICATIONS LISTED, STATE THE LIMITING CONDITIONS OF OPERATION, APPLICABILITY; SRO:
IDENTIFY ACTION STATEMENTS OF ONE HOUR OR LESS AND STATE THE BASES AND ACTION 49 t
. -. ~.
LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES STATEMENTS OF ONE HOUR OR LESS FOR THE TECH.
SPECS. IN ADDITION TO THE ABOVE.
- 3.4.1.3 (RCS hot shutdown)
- 3.4.1.4.1 (RCS cold shutdown, loops filled) 3.4.1.4.2 'RCS cold shutdown, loops not filled)
- 3.4.9.3 (RCS < Ops)
- 3.5.2 (ECCS T 2 350 degrees F)
- 3.5.3 (ECCS Tavg < 350 degrees F)
- 3.9.8.1.(RF h 90 water level)
- 3.9.8.2 (RF low water level)
Refer to the Technical Specifications and review each item as required.
18.
EXPLAIN HOW EACH THE FOLLOWINO CAUSES A LOSS OF RHR CAPABILITY a.
PUMP TRIPS Without the pump running there is no flow due to loss of driving head b.
CLOSURE OF RRR SUCTION Will require tripping FER pump c.
LOW LEVEL IN RCS This can cause vortexing at the RCS loop suction penetration resulting in air being drawn into the RHR pump causing them to become air bound with accompanying loss of flow, d.
EECESSIVE FLOW RATE IN RHR SYSTEM This could result in vortexing-at RCS-RNR penetration with subsequent air binding of RHR pumps' s
- 19. - DETERMINE THE RHR SYSTEM RESPONSE AND DESCRIBE THE APPROPRIATE CORRECTIVE' ACTION FOR THE FOLLOWINO:
a.
LOSS OF AIR'OR ELECTRICAL POWER TO FCV 606 OR 618 606' fails open - this will result:in-cooldown rate being at max value which may be excessive 50
. ~...
LO-LP-12101-20-C III.
LESSON OUTLINE NOTES Manually open HX bypass will reduce flow through HX until 606 can to restored to normal.
Shift RHR train is necessary 618 fails closed - this will resul't in reduced RHR flow.
Ensure miniflow if functioning properly, shift RHR trains may be required if cause can.not be found and corrected b.
RCS WIDE RANGE PRESSURE TRANSHITTER FAILURE (HIGH)
RHR suction valves will auto close Stop RHR pump (s) c.
FAILURE OF OR INACCURATE LEVEL INDICATION This could result in actual RCS level dropping, overtime, due to normal leakage, etc. to the point of allowing vortexing to occur and subsequent air binding of RHR pumps Shift to only one train of RHR may be necessary to reduce flow - correct level indication B.
Review Non-Licensed Operator Objectives 1.
LIST THE THREE FUNCTIONS OF THE RHR SYSTEM To transfer heat-from the RCS to the component Cooling Water System (CCW) in order to reduce the temperature of the regetor coolant to ce ld shutdown temperature (140 F).
To serve as part-of the ECCS daring the low-pressure-injection and recirculation phases following a LOCA To transfer refueling water between the RWST and the-reactor cavity before and after
-refueling.
2.
DRAW A ONE-LINE DIAGRAM OF THE RHR SYSTEM WITH MAJOR VALVES'SHOWN IN POSITION FOR A NORMAL PLANT COOLDOWN. THE DRAWING HUST-INCLUDE THE FOLLOWING (VALVE NUMBERS ARE NOT REQUIRED ON 4
51 v.,,,
m
LO-LP-12101-20-C 1II.- LESSON OUTLINE NOTES THE DRAWING)t
. a'.
TEMPERATURE CONTROL VALVES (606 AND 607) b.
PUMP INLET ISOLATION VALVES (8701 A/B
-AND 6702 A/8) c.
PUMP.MINITLOW CONTROL VALVES (610 AND 641) d.
PUMP SUCTION VALVES (8812 A/B AND 8811 A/8)-
e.
HOT LEO CROSSOVER ISOLATION VALVES (8716-A/S) f.
RECIRCULATION VALVES (8804 A/B) g..
COLD LEG INJECTION VALVE (8809 A/B) h.
RHR BYPAS$ VALVES (618 AND 619)
- 1. -RHR PUNPS j.
I1HR HX k.
INTERIACES 1)
- 2) RCS
-5)
- 6) RHR ME/LW
- 7) RR3 HUT Use NL-TP-12101-00-004 tn review the required
~ drawing.
3.
STATE THE~ FUNCTION AND DESIGN PARAMETERS (PRESSURE, FLOW) FOR THE RHR-PUMPS Provides driving head for RHR flow 600 peig discharge pressure 375 feet TDH 52
LO-LP-12101-20-C III.
LESSON OUTLINE:
NOTES 3000 gpm 4.
LIST THE ELECTRICAL SUPPLIES FOR THE FOLLOdING COMPONENTG a.
RHR PUMPS 1A - 1AA02 1B - 10A03 b.
PUMP INLET ISOLATION VALVES (INVERTER SUPPLILD) 8701A - HCCIABE 8702A - INV 1DD116 8701B - INV 1CD115 870?B - McClBBE 5.
DESCRIBE HOW THE RHR IS PROTECTED FROM OVER-PRESSURIZATION.
Suction and discharge relief valves 6.
WITH REGARD TO THE RHR SYSTEM, DESCRISE HOW TEMPERATURE AND FLOW ARF, CONTROLLED DURING NORMAL COOLDOWN.
RHR HX outlet flow control valve is manually positioned to control the flow through the heat exchanger which will in turn control the cooldown rate of the RCS.
The RHR heat exchanger byptus valve will auto-matically adjust to maintain total system flow as set by the cperator.
7.
DESCRIBE THE MINIFLOW LINE, EXPLAINING ITS PURPOSE AND OPERATION.
INCLUDE SETPOINTS.
The miniflow recire valve operates to maintain the miniane, flow requirements of the RHR pump to prevent pump cavitation by removing pump heat.
In auto the valve opens when flow ie reduced to 700 gpm and closes when the flow is increased to 1400 gpm as measured at the RHR pump outlet S.
BRIEFLY DESCRIBE THE FLOWPATH OF THE RHR SYSTEM FOR THE FOLLOWING OPERATIONS:
a.
NORMAL COOLDOWN sa j
i 1
--, - - ~
~. -.. -. ~.. -. ~.
~ ~.--..,
.LO-LP-12101-20-C-III.
LESSON OUTLINE:
NOTES ~
~~
RCS loops 1 and 4 hot legs, RHR pump suction valves, RHR pumps, RHR HX, RHR HX flow control valve, RCS cold legs b.
FILLING THE REFUELING CAVITY RWST.
RWST suction to Rl!R valves, RHR pump, RHR HX outlet flow control valve RCS cold-leg, c.
DRAINING THE REFUELING CAVITY RCS-loop 1 or 4, RHR suction valve, RHR pump, RHR HX, RHR HX outlet flow control valve, hot leg crossover isolation valve, RHR to RWST return valve, RWST d.
INJECTION FROH EMERGENCY CORE COOLING RWST, RWST to RNR suction valves, RHR pump, hMR HX, RHR HX outlet flow control valve, RCS cold legs.
e.
HOT LEG INJECTION (RECIRC)
Ctmt. sump, RHR pump, RHR HX, RCS hot legs, and CVCS CCP suction to RCS loops 1,-2, 3 and 4 cold legs.
Also from RHR Trn B to SIP suction to hot lege 1, 2, 3 and-4 9.
DEFINE THE TERH " SOLID. PLANT OPERATION".
BASICALLY DESCRIBE'HOW PRESSURE IS CONTROLLED IN THIS MODE.
RCS an1 PRER full. Press. controlled.by relative difference between chg and letdown.
l
\\
10.
DESCRIBE HOW THE.FOLLOWING-SYSTEMS INTERFACE WITH THE RNR SYSTEM.
INCLUDE A BRIEF EXPLANATION OF THEIR PURPOSE:
a.
.RCS Hot and cold leg injection pathe-for ECCS Normal cooldcwn from loope i and-4
-and return to RCS cold legs b.
RWST Supply of borated water during ECCS
$4 j
I
- s..f a
S.*
A.a
+
4.2w.,
in u _...,
LO-LP-12101-20-C~
III.
LESSON-OUTLINE:
NOTES
~
c.
CONTAINMENT Sump collects borated watet-for recirculation phase i
d.
CVCS RHR cleanup Pressure control i
e.
SAFETY INJECTION Same lines as RHR for SI f.
PRT collects discharge from suction reliefs.
g.
BRU HUT collecto discharge from discharge reliefs.
h.
CCW Supplies RHR heat exchangers and pump seal coolers L.
NSCW Supplies RHR pump motor cooler 11.~
DISCUSS THE IMPORTANCE OF ACCURATE LOCAL LEVEL INDICATION FOR THE RCS DURING RCS DRAINING OPERATIONS. -INCLUDE AN EEPLANATION OF LEVEL INDICATION RESPONSE DUE TO CHANGES IN VESSEL LEVEL.
Vessel level indication being inaccurate may result in lowering water level to point of causing a loss of RHR due to air binding of pumps from vortexing-in suction at loop penetration.
55 i
I LO-LP-12101-20-C SUKKARY OF IEN 86.101, ATTACH. 1 i
LOSS OF RHR EVENTS AT PURs san onofre Prior to partially draining the RCS for SG maintenance at San onofre 2, a CE designed reactor, wide-and narrow-range RCS-level instruments were put in service by installing their temporary connections and calibrating them.
Tygon tubing was also installed temporarily to provide a sight gauge for monitoring RCS water level. Thus, three devices were available for monitoring water level in the system.
To permit repairs, personnel began draining vessel water level to 17.5 inches above the bottom of the 42-inch diameter hot legs. One of the hot legs supplies water to the inlet side of the shutdown cooling system (SDCS) through a connection in the bottom of the pipe. While the water level was being lowered, a vortex formed on the suction side of the low pressure SI (LPSI) pump.
The vortex entrained' air causing the pump to become air bound, loss of SDCS flow, and thus loss of decay heat removal. The pump was secured and the redundant pump was started.
It, too, became air bound and was secured.
To reestablish flow through the
-SDCS, the system was vented, and the water level in the reactor vessel was raised.. Seventy minutes after the first indication of vortexing, decay heat removal was again established. Haanwhile, the hot leg temperature-increawad-from 114 to 210 degrees F, and local boiling occurred in the reactor cere. Steam and 2 curies of radionuclides were released to containment.
The operators did not trust installed narrow and wide-range level instrumentation becauss of its tendency to oscillate during the use of certain equipment, and were relying on the temporary tygon tubing sight gauge for level indication. However, during installation and filling of the tygon tubing, an air bubble was inadvertently trapped in the tubing causing to read high by 10.5 inchee.
Further, the reference scale for
]
the~ tubing was displaced by 2.5 inches in the upward direction causing a total error of 13 inches (high). Thus, lowering level to 17.5 inches as indicated on sight gauge would have lowered actual level to 4.5 inches.
-(Although the operator did not have confidence in the-narrow range instrument,-its reading was approximately correct at that time.)
Vortexing started at an actus1 level of about 9.5 inches.
Lack of knowledge about the performance of the system at low water levels and unreliable instrumentation-for monitoring water level were the principal causes of this event.
Secuovah 1 Sequoyah 1,_a Westinghouse reactor, was in cold shutdown with-the water level in the reactor vessel 4 inches below the contare of the hot leg nozzles.
RHR Train B was in servict for removal of decay heat.
During an-evolution to put Train A in service, RHR Pump A was started and then Pump B was secured. Running both pumps simultaneously with low reactor vessel water level caused 56
.,-~
LO-LP-12101-20-C initiation of vortexing and air binding in Pump A.
The pump was secured, and Pump B was restarted and operated normally. The alignment of Train A was restarted, but this time it became air bound and was secured.
Vessel level was raised, and about 43 minutes after loss of.
decay heat removal, Pump A was vented and returned to service.
Pump B was ventad, demonstrated operable and daenergized.
Both pumps take suction from the same hot leg, whose level would not support operation of both pumps simultaneously. The procedure for operating RHR with partially drained vessel did not adequately reilect the relationship between RRR flow rate and water level for the onset of vortexing in the suction line for the RHR pumps.
Catawba 1 Catawta 1 (Westinghouse) was in cold shutdown with RHR B in service to ramove decay heat.
Although RHR was inoperable due to maintenance, the licensee started to lower the water level in the reactor vessel for maintenance. Whilo draining was in progress, erratic performance of RHR Pump 3 indicated that vortexing, air entrainment, and air binding were occurring.
The pump was secured and vessel level was raised using a charging pump aligned with RWST.
RHR Pump B was returned to service.
Temperature of the RCS peaked at 177 degrees F.
It is believed that information obtained from inaccurate level instrumentation contributed to loss of RHR at this plant whose procedure for lowering water level in the vessel does limit RHR flow as a function of level, apparently to preclude the onset ;of vortexing.
Further,-the licensee incurred an increased risk of loss of RHR flow by lowering water level with one train of RHR cooling cuu of service. A Tech Spec LCO requires that one RHR train be operating and that the other be operable under the conditions present. The operators concluded incorrectly that water level could be lowered if corrective action had been initiated to comply with action statement for that limiting condition for operation.
Diablo Canyon IEN 87,023 Event Initiation A plant engineer opened a valve to perform a local leak rate test creating a leak from the RCS Loss of RHR Cooling RHR pump began cavitating. Operator shutdown the running pump.
Operator started and then shutdown the standby pump.
It also cavitated.
57
LO-LP-12101-20-C RHR cooling capability was lost.
There was no method of monitoring incore temperatures.
The validity of the temporary RV level indication was,
suspected. An operator was dispatched to check local RV tygon tube indication. The operator attempted to verify RCS integrity.
Operators attempted to stop the leak. NOUE declared.
Leak stopped after approximately 1.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> by Engineer, operators refilled the system from the RWST via a RHP pump.
Fundamental causes and Discussion Topics RV level indication system problems.
Improperly seated valve.
Operator awareness of evolutions in progress.
Containment integrity problems.
Hid loop operation.
Instrumentation.
Communications problems.
Event misclassification.
Post-event Technical and Administrative Investigative Actions taken at Plant Vogtle Several procedure related deficiencies were identified and corrected.
Procedures 12000 - Refueling Recovery, 12006 - Unit Cooldown to Cold shutdown, and 12007 - Refueling Entry have been revised to require at least 2 incore thermocouples to be maintained operable during periods of mid-loop operation.
If the RPV head is removed the disconnection of these thermocouples will be d9 layed until the last possible moment and restored at the first opportunity after the head is replaced.
Guidelines for monitoring reactor vessel level when draining or filling the RCS have been expanded. More information concerning the param6ters to be monitored is also given in procedures 12000 - Refueling Rocovery, 12006 - Unit Cooldown to Cold shutdown and 12007 - Refueling Entry.
Continuous monitoring when changing levels when PER level is < 17%
Periodic level checks are required between the control room indicators and the tygon tube every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
A continuous tygon tube watch is required if no control room indicator is available.
A continuous monitoring of the tygon tube level during mid-loop operation is required by 13005 Reactor Coolant System Draining.
RHR train operation guidance is given.
One train in operation with a flow of 3000 gpm in procedures 12000 - Refueling Recovery, 12006 - Unit Cooldown to cold Shutdown, 12007 - Refueling Entry, 13011 - Residual Heat Removal System, and 13005 - Reactor Coolant System Draining.
58 l
LO-LP-12101-;0-C During the draining of the steam generator U tubes guidance is given for expected RPV level responses in procedure 13005 Reactor Coolant System Draining.
Minimum level of 188 feet is maintained whenever the RHR is in service per procedures 12000 - Refueling Recover, 12006 - Unit Cooldown to Cold shutdown, 12007 - Refueling Entry, 13305 - Reactor Coolant System Draining.
13005 - Reactor Coolant System Draining instructs the operator that only one drain path shall be used at a time and operators shall be aware of the path being used.
Log entries shall be made'to keep personnel aware of drain paths.
13005 - Reactor Coolant System Draining instructs the operator that if draining via the RCDT, do not drain from the same loop (s) that are being monitored for level.
Thus filling or draining' operations should not have an adverse affect on level indication.
13011 - RHR system, has the operator disable valves 8804 A/B when placing the RHR system into service.
This disables the opening of 8812 A/B from the control root.
These valves, however, are operable from -5e remote shutdown panels if needed to refill air bound RHR pump suctions on a loss of RHR cooling.
Hardware Changes Temporary reactor vessel level indicators are to be installed on the control board using SI accumulator level instruments.
Both alarm functions and t onding information will be available.
An evaluation of the removal of interlocks associated with the RHR loop suction valves is in progcess End "'023 i
l 57
)
kbE 5TATEl{E Following completion of this lesson, the student will possess those knowledges systematically identified for the performance of the RHR SYSTEM tasks.
T O B O O KM W VES
~
1, (A) List the three functions of the RHR system.
2, (A) Draw a one line diagram of the RHR System with major valves shown in position for a normal plant cooldown.
The drawing must include the following (valve numbers are not required on the drawine,):
temperature control valves (606 and 607)
- pump inlet isolation valves (8701 A/B and 8702 A/B) pump miniflow control valves (610 and 611)
- pump suction valves (8812 A/B and 8811 A/B) hot leg crossover isolation valves (8716 A/B) recirculation valves (8804 A/B) ccid leg injection valve (8809 A/B)
RHR bypass valves (618 ano 619)
- RHR Hx/CCW BRS HUT
- 3. (A) State the function and design parameters (pressure, flow) for the-RHR pumps,
- 4. (A) List the electrical supplies for the fallowing components:
- a. RNR pumps
- b. Pump inlet isolation valves (inverter supplied) 5 (A) Describe how the RHR System is protected from overpressurization.
6, (A) Vith regard to the RHR system describe how temperature and flow are controlled during normal cooldown.
- 7. (A) Describe the miniflow line, explaining its purpose and operation.
Include setpoints.
1
OBJECTIVES FOR NL LP 12101 CONTINUED,
- 8. (A)_ Briefly describe the_ flowpath of the RilR system for the following operations:
- a. Normal cooldovn-b:. Tilling the refueling cavity
- c. Draining the refueling cavity
= d -Injection for emergency core cooling
- e. Ilot leg injection _(recirculation)
- 9. (A) Define'the term " solid plant operation." Basically describe how pressure is controlled in this mode.
- 10..(A) Describe how the.following systems interface with the RilR system, Include a brief explanation of their purpose:
a-.
- c. Containment d, CVCS e., Safety. injection
- f. PRT
- g. BRS tlUT_
h.-CCV--
- 1. NSCW
- 11. (A) Discuss the importance of accurate local' level indication for the
~
RCS during RCS draining operations.
Include an explanation of-level-indication response due to changes.in vessel level, s
Page
_ _ _, _ _,... ~.,..
M-J1J6 LICENSED OPERATOR OBJEGIIVES LO-LP 12101.c I
PURPOSE STATEMENT Following coepletion of this lesson, the student will possess those knowledges systematically identified for the performance of the RHR SYSTEM tasks.
11 LIiDFWJRTIVES 1.
List the three functions of the RHR System.
(KSA numbers: 005CEN0004) 2.
Given a one line diagram of the RHR Lvstem, identify the major components and valves (include all valves and instrumentation that indicate or are controlled from the main control board),
Indicate valve lineups for S1 injection, SI recirculation and refueling.
3.
List the design temperature and pressure for the KHR system, 4.
List the RHR pump motor start limitations.
5.
List the power supply for the RHR pumps.
(KSA numbers: 005000K201) 6.
State all auto start signals for the RHR pumps.
7.
Describe how the RHR System is protected from overpressuri:ation.
Include setpoints where applicable.
(KSA numbers: 005000K401) 8.
Describe the associated logic for the operation of the following RHR valves.
Include interlocks and setpoints:
~
- a. RCS suction valves b heat exchanger-outlet and bypass valve
- c. mini-flow recirculation valves
- d. RWST suction valves
- e. containment sump suction valves (KSA numbers: 005000K403, 005000K407, 005000K410) 9.
Describe how the RHR System meets the requirements for safety-grade cold shutdown.
(KSA numbers: 005000K401) 10.
State the function and purpose of RHR/ECCS lockout switches on the main control board and identify the RHR valves equipped with lockouts.
(KSA numbers: 005000K407) 1 i
___a
~
OBJECTIVES FOR LO.iP.12101 CONTINUED.
11.
Describe how the following systems interface with the RHR System, a, RCS
- b. RVST
- c. Containment
-d.
CVCS e.
Safety Injection
- f. PRT
- g. BRS HUT
- h. CCV
- i. NSCW (KSA numbers: 00$000K101, 005000K104, 00$000K106) 12.
Briefly describe the flovpath through the RHR System for the following operations:
a, normal cooldown i
b, emergency core cooling injection
- c. recirculation phase i
- d. hot leg injection (KSA numbers: 005000K411, 005000K412. 005000K402) i l
13.
Describe the major steps to complete the following operations:
- a. Place RRR in service for cooldown from mode 3 to mode 5
- b. Remove RHR from service from mode 5 to mede 3 (KSA numbers: 005000K411) 14.
Describe how RCS pressure is controlled during solid plant operation.
(KSA numbers: 005 GEN 0001) 15.
Explain the operating precautions and limitations of the RHR System which relate to the following; l
a, thermal shock of RCS components b, pressure and temperature limitations on RHR System
- c. Limitation on train operation when RCS level is i
mid. nozzle (KSA numbers: 005CEN0001)
)
16.
Discuss the importance of accurate local level indication for the RCS during RCS draining operations, (KSA numbers: 005000K409) l 1
-0BJECTIVES FOR LO LP 12101 CONTINUED.
17.
For each of the following_ Technical Specifications listed, state the limiting-condition of operation. applicability.
SRO, identify
. action statements of one hour or less and state the bases and action statements of one hour or less for the Tech Specs ~ in addition to the above.
3.4.1.3 (RCS hot shutdown) i
-3.4.1.4.1 (RCS cold shutdown, loops filled) 3.4.1,4.2 (RCS cold shutdown, loops not filled)
-3.4,9.3 (RCS < Ops) 3.5.2 (ECCS Tavg 350 degrees F) 3.5.3 (ECCS Tavg < 350 degrees F)
+3.9.8.l'(RF high water level)
-3.9.8.2 (RF low water level)
(KSA numbers: 005CEN0006, 005CEN0005) 18.
Explain how each of the followin6 can caue,e a loss of RHR capability:
- a. pump trips b, closure of RHR suction valves
- c. low level in RCS
- d. excessive flowrate in RHR System (KSA. numbers:-005 GEN 0001)
~
19.
Determine the RHR System response and describe the appropriate corrective actions for the following:
loss of air-or electrical power to FCV 606 or 618 a,
b, RCS RVLIS pressure transmitter failure.(high) c, failure of or inaccurate temporary. level indication (KSA numbers: 0005CEN008)
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