ML20040A971
| ML20040A971 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  |
| Issue date: | 04/25/1980 |
| From: | PACIFIC GAS & ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20040A967 | List: |
| References | |
| NUDOCS 8201230020 | |
| Download: ML20040A971 (10) | |
Text
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EXHIBIT 7 is.nsa ccensspo:msxes PACIFIC GAS AND ELECTRIC COMPANY DEPARTME?lT OF NUCLEAR PLANT OPEPATI0h5 DIABLO CANYON POWER PLANT UNIT NOS. 1 AND 2 EMERGENCY OPEPATING FROCEDURE fl0. OP-13 TITLE: MALFUNCTION OF REACTOR PRESSURE CONTROL SYSTEM SCOPE The purpose of this procedure is to provide instructions to be followed in th'e event of a malfunction of the reactor pressure control system.
For simplicit this procedure is subdivided into four parts as follows:
g PART A.
Pressurizer Pressure Channel fz.iis high.
t PART B:
Stuck open spray valve.
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i PART C:
Pressurizer heater malfunction.'
g.a g
PART D:
Stuck open or leaking power operated relief valve.r
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1 PART A:
PRESSURIZER PRESSURE CHANNEL FAILS HIGH e
a i
SYMPTOMS j
1.
Failed channel will indicate high pressure.
Give the high pressurizer pressure alarm (PK05-16) and trip Ge a~ssocTated reactor ti-ip bystable (PK05-06).
2.
Other pressure channels show actual pressure is decreasing and gives low pressure alarm (PK05-17).
3.
PRT pressure, level and temperature indicators on VS-2 show abnormally high indication.
4.
" Pressurizer PORV Temperature High" annunciator alarms (PK05-23).
AUTOMATIC ACTIONS 1.
If the controllino channel fails high, a.'Both spray valves open.
b.
All pressurizer heaters de-energized.
c.
PCV-455C opens (closes again when pressure decreases to 2185 psig).
PAGE 1
0F 10 REVISION 1
DATE 4/25/80 APPROVAL 4
8201230020 820114 PDR ADOCK 05000275 0
DIABLO CANYON P05'ER PLANT UNTT N05.
1 AND 2 EMERGENCY OPERATlNG PROCEDURE NO OP-13 TITLE: MALFUNCTION'0F REACTOR PRESSURE CONTROL SYSTEM 2.
If the selected protection ' channel fails high, PCV-474 and PCV-456 will open (but close wnen actual pressure decreases to 2185 psig).
3.
Possible reactor trip on low pressure.
4.
Possible safety injection signal on low pressure.
OBJECTIVES 1.
To regain pressure. control by selecting the alternate control channel to terminate event without a reactor trip.
2.
To restore pressurizer pressure and level to referenc.e values.
3.
To trip all the bistables associated with the failed channel within one hour.
IMMEDIATE CPERATOR ACTIONS ACTION COMMENTS 1.
Select alternate channel for pressure 1.
Insure that the position control on selector switch P/455A.
selected does not utilize
~
the defective channel.
2.
Verify spray valves closed, PORV's closed and heaters energized.
3.
If step 2 does not occur, place the master pressure controller (HC-455K) in manual and return pressure to~
no'rmal.
4.
Stop any unit load changes in progress.
5.
If a reactor trip occurs, refer to Emergency Operating Procedure No. OP-5 6.
If a safety injection occurs, refer to Emergency Operating Procedure No. OP-0.
SUBSEOUENTOPERATORACTIOE ACTION COMMENTS 1
Select the pressurizer pressure recorder to record a valid pressure channel (P/455B).
PAGE 2
or,_10 REVISION I
DATE 4/25/80
DIABLO CANYON POWER PLANT UNIT N05. 1 AND 2 EMERGENCY OPERATZNG PROCEDURE N0. OP-13 TfTLE: MALFUNCTION OF. REACTOR PRESSURE CONTROL SYSTEM ACTION COMMENTS 2.
If a reactor trip does not occur:
a.
Ensure pressurizer level and pres-sure return to their normal value.
b.
Within one hour trip, all the by-b.
See table III A-1 in Volume stables associated with the failed 9 of DCPP Plant Manual.
pressurizer pressure channel.
3.
Refer to Operating Procedure No. A-4B to return the PRT to normal.
4.
Whenever the RCS experiences an abnormal pressure transient, the plant is in a condition designated as an UNUSUAL EVENT. Carry out the instructions given in Emergency Procedures General Appendix 2 (Notification of Off-Site Personnel in the Event of an Emergency).
PART B: STUCK OPEN SPRAY VALVE SYMPTOMS 1.
All pressurizer pressure channels show decreasing pressure.
2.
Low pressurizer pressure alarm (PK05-17).
3.
Pressurizer heaters'and spray on it the same time.
4.
Pressurizer surge line temperature is lower than normal due to upsurge and will give an alarm.
AUTOMATIC ACTIONS 1.
Backup heater energize.
2.
Possible reactor trip on low pressure.
3.
Possible safety injection signal.
OBJECTIVES 1.
To terminate spray valve action.
2.
To restore pressure control.
PAGE 3 0F 10 REVISION 1
DATE 4/25/80
l DIABLO CANYON POWER PLANT UNIT NOS.
1 AND 2 EMERGEn;Y OPERATING PROCEDURE OP-13 TTTLE: MALFUNCTION OF REACTOR PRESSURE CONTROL SYSTEM IMMEDIATE OPERATOR ACTION ACTION COMMENTS 1.
Piece affected spray valve controller to manual and close the spray valve.
2.
If spray valve does not completely close, ensure all heater groups are energized.
3.
Quickly drop load, if necessary, to 3.
If the RCP is tripped at reduce the power level to about 20%.
a power level much greater Then trip the reactor coolant pump of than 20%, the reactor will the loop associated with the defective probably trip on low steam spray valve.
generator level.
If the RCP is tripped above 35% power, the reactor will trip.
NOTE:
Loop No. 1 feeds PCV-455A and Loop No. 2 feeds PCV-4558.
4.
If step 3, above, results in a reactor trip, then:
a.
Trip the reactor coolant pump of the loop associated with the affected spray valve.
b.
Proceed to Emergency Operating Procedure No. OP-5.
5.
If a safety injection occurs, proceed to Emergency Operating Procedure No. OP-0.
SUBSEOUENT OPERATOR ACTIONS ACTION COMMENTS 1.
If system pressure was maintained without a reactor trip.
a Return system to normal pressure' a.
Us= the minimum number of by manual heater operation.
heater banks to maintain pressure.
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PAGE 4 0F 10 REVISION 1
DATE 4/25/80
DIABLO CANYON POWER PLNiT UNIT NOS. 1 AND 2 EMERGENCY OPEPATING PROCEDURE NO. OP-13 TITLE: MALFUNCTION OF REACTOR PRESSURE CONTROL SYSTEM ACTION COMMENTS b.
If normal spray is not useable or inaffective when system pressure is restored, use auxiliary spray or use a pressurizer relief.
Follow step No. 1C or 10 below.
~
c.
If auxiliary spray is needed.
- 1) Ensure letdown is not isolated.
1)
If letdown is isolated or becomes isolated, auxiliary spray cannot be used due to the AT limit (Tech Spec 3.4.9.2).
- 2) Close the normal charging path to the reactor coolant loop.
- 3) Monitor and maintain adequate RCP seal injection.
- 4) Open auxiliary spray valve to control pressure.
d.
If a pressurizer relief is needed for pressure control,
- 1) Close one pressurizer relief isolation valve.
- 2) When the isolation valve is closed, open its' associated PORV.
- 3) The motor operated isolation va.lve can now be jogged for pressure control.
e.
If a spray valve is stuck open, evaluate the conditions necessary l
for containment entry to repair or isolate the defective valve.
f.
If the defective valve was closed, repair if possible or evaluate plant conditions to determine the feasibility of continued power operation in such, a mode.
6 PAGE 5
op 10 REVISION I
DATE 4/25/80 l
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