ML20148R859
| ML20148R859 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 01/29/1988 |
| From: | DETROIT EDISON CO. |
| To: | |
| Shared Package | |
| ML20148R834 | List: |
| References | |
| NUDOCS 8802020291 | |
| Download: ML20148R859 (17) | |
Text
,
115M' A 10 yarne 3/4 6-27 Primary Containment Gaseous Radioactivity Monitor Isolation Valves Inboard: T50-F450 60 T50-F451 60
- t Outboard: T50-F455 60 [
T50-F456 60 i I
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i 8802020291 880129 PDR ADOCK 05000341 P PDR i
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1
I TABLE 3.6.3-1 (Continued)
PRIMARY CONTAINMENT ISOLATION VALVES i . ,
TABLE NOTATIONS (Continued) r t
15.
Group 15 - Traversina In-Core (TIP) System (Continued)
NOTE:
Either of these signals initiate TIP withdrawal which results in automatic closure of the TIP Ball Valves when '
the TIP probe has entered the shield cask.
- 16. Group 16 - Nitrocen inertina System Reactor Vessel Low Water Level - Level 2 Drywell Pressure - High Fuel Pool Ventilation Exhaust Radiation - High l
17.
Group 17 - Recirculation Pump System and Prim.,4 N4..-.,4 R&w MJ4.?,y 5,39,,
Reactor Vessel Low Water Level - Level 2 Orywell Pressure High
' 13. Group 18 - Primary Containment Pneumatic Supply System Reactor Vessel Low Water level - Level 2 J
Orywell Pressure - High a (b) These valves are hydrostatically leak tested. [
RWCU Water Temperature - High automatically closes G33 F004, outboard ,
(c) isolation, and G33-F001, inboard isolation. !
Also closes automatically as a result of Torus Room Floor Orain Sump 3
(d) Level - High - High and Drywell Floor Orain Sump Level - High - High.
7 These valves may be closed remotely from one of the following locations: I (e) t
- 1) control room.
i
~ 2) their respective local panels.
(f) Will automatically reposition as a result of the actuation of the LPCI Loop Selection Logic.
(g) Will automatically close when the corresponding RHR loco flow is greater than 1500 gpm.
Will automatically close when the corresponding core spray loop flow is (h) greater than approximately 775 gpm.
Will automatically close when a) HPCI Turbine Steam Stop valve E41 F067 (1) closes or b) HPCI Turbine Steam Supply Isolation Valve E41-F001 closes. [
(j) Will automatically close as a result of the condition listed in Note (i),
t above, as well as when HPCI flow is greater than 1200 gpm.
t
+
1 k
3/4 6-46 FERMI - UNIT 2
Attachnent to MC-88-0004 Page 13 l
l IFIRR PAGE CHMGES
UFSAR SECTION Paae No. Description of Chance 6.2.4.2.2.3.1 77 Mded PCIMS to the CDC 56 alternatives -
"two icolation valves outside containnent" .
6.2.4.2.2.3.2 79 Corrected the penetration nunber to X-4W.
81 Mded PCINS to the UFSAR section describing "lines connecting to the drywell".
Table 6.2-2 161 Mded PCINS sanple suction valves to the table.
189 Corrected the valve position information for T5000F408A.
189 Mded the PCINS sanple return valves to the table.
Table 6.2-15 228 Mded a reference / consent for the PCINS (suction) at X48.
233 Mded a reference /conment for the PCINS (return) at X-215.
235 Mded penetratlon "PCIES" to depict the nultiple roles for the X48 and X215 penetrations "essential" versus "non-essen tial" .
Table 6.2-16 236 Mded PCINS "non-essential" classification.
7.3.2.2.7.1 41 Mded ICIES to the listing of reactor level 2 isolation signals.
! 7.3.2.2.7.6 43 Corrected the high drywell pressure listing by m3 ding torus water rnanagerent.
Mded PCIES to the list of high drywell pressure isolation signals.
'j Figures 7.6-11 Revisions to P&ID 6I721-2679-1 for the
& 11.4-1 PCIN isolation valves.
! 7.6.1.12.1.3 37 Mded information to clarify that PCINS i isolation valves use interruptible air.
I i
i 1
FERMl 2 UFSAR Fynetration No.
System Postaccident suppression pool atmosphere sample As stated in GDC 56, two isolation valves--one inside and one outside the containment--are required in lines that penetrate the ,
primary containment and connect directly to the containment '
atacJphere. However, @c 56 allows for alternatives to these explicit isolation requirements where the acceptable basis for ,.
each alternative is defined. The following are alternatives to explicit conformance with GDC 56. Notes in Table 6.2-2 identify the alternative basis to which each penetration is designed.
Two Isolation Valves outside containment - A M. '
1!,e Primary Containment Radiation Monitor Systen (PCRMS) is associated with Division I of the Primary Containment Atmosphere Monitoring i Systes (PCAMS). The non-essential PCRMS has two isolation valves on the inlet and two isolation valves on the outlet. These isolation valves are a normally open spring-to-close solenoid operated globe
/ valve and air operated ball valve. These inlet and outlet lines are
( connected to the containment staosphere via PCAMS piping during normal operation. These valves receive containment isolation signals on the postulated 14CA.
For lines that connect to the suppression pool, an isolation valve located inside the containment would necessitate placement of the valve either under water or in a high-humidity, nonacces-sible area. Pluch placement would subject these valves to an extremely hostile environment, which could compromise their reli- ~
ability and prevent routine inspection and maintenance, Thus, as an alternative to the explicit requirements of GDC 56 for lines in ESF or ESF-related Jystans, both isolation valves are located outcid6, and es cicJe to, the containment wall as practical.
Relief Valves aw Isolation Valvee Relief valves are provided in the RER, care spray, BPCI, RCIC, and combustible gas control (C0C) systems e.s overpressure-l protection devices. These valves are required for the design
[
of Class B systess according to the ASME B&PV Code, subsec-l ' tion NC-7000. The valves are installed in a manner that ensures t
their correct operation and reliability. Further, the Code l t requires that no stop valves or other devices be placed (in relation to a pressure relief device) so that it could impair the overpressure protection offered by the relief valve itself.
Relief valves installed in these lines provide thic required level of pr6tection, and, if required to operate, would route the diverted fluid to the suppression pool.
Because of the orientation required, each of these relief valves is an isolation valve for the applicable penetration. The piping and valve designs are Quality Group B, category I, and will with-stand temperatures and pressures at least equal to the contain-ment design pressure and temperature. Shot.1d the postulated LOCA occur, containment pressure would be felt on the downstream side of the relief valve, and would act in conjunction with the spring pressure setting of the relief valve to further enhance seating. ,
Remote Manual Isolation Valves i
Remote manual valves are used as containment isolation valves in ESF and ESF-related systems. These systems include RHR, core 6.2-77
FERM12 UFSAR Penetration No._ System X-18 Drywell floor drain sump pump discharge X-19 Drywell equipment drain sump pump discharge X-20 Demineralized service water to drywell X-21 Service air to drywell X-22 Control air and N2 to drywell X-23 RBCCW supply X-24 RBCCW return X-25 Drywell exhaust X-26 Drywell N2 and air inlet X-27(a,b,c, containment atmosphere sample d,e,f) and postaccident drywell atmos-phere sample (X-27b only)
X-29B(b,c)
X-293e Drywell instrumentation X-31Ba Drywell on-line pressure control X-34(A,B) RBCCW supply and return X-35G TIP N2 Purge line X-36 N2 to drywell X-39(A B) RHR to containment spray header X-44 CGC suction X-47(a,b) Reactor protection system X-47(c) Nitrogen inerting instrumentation X-47e Drywell instrumentation X-4 8 ( a ,b , c , Containment atmosphere sample d,e,f) and postaccident drywell atmos-g phere sample ( 6 only) 4 X48f
$6Vl1C 6.2-79
FERMI 2 UFSAR Nuclear-grade materials are used throughout the fabrication of the piping system. They will maintain their integrity should the
~
containment experience its design temperature and pressure tran-sient. hus, as an alterna':ive to the explicit requirements of GDC 56 for such lines in ESF or ESF-related systems, a single air-operated isolation valve or solenoid-operated isolation valve )
is used outside the containment to enhance system reliability. ,,, l The lines that connect the non-essential Primary Containment Radiation i
Monitoring Systes (PCRMS) to Division I of the closed outside d containment loop of the Primary Containsent Monitoring Systems PCAMS I have two isolation valves outside containment for both the inlet and l I outlet of the PCRMS. The PCRMS utilises commen piping of PCAMS l therefore the valves are outside containaant and placed as close as I practical to the PCAMS piping loop. All other requiresents of GDC 56 are met.
The drywell postaccident atmosphere sample lines contain two A4[ !
solenoid-operated globe isolation valves outside the contain-ment. Rose lines are connected to the normal containment atmos-phere sample systen lines outside the containment. These valves are closed during normal reactor operation and are opened only i during postaccident conditions.
6.2.4.2.2.4 _ General Design Criterion 57 General Design Criterion 57 in 10 CFR .30 states Each line that penetrates primary reactor containment and is neither part of the reactor coolant pressure boundary nor connected directly to the containment atmosphere shall have at least one containment isolation valve dich shall be either automatic, or locked closed, or capable of remote manual operation. h is valve shall be outside the contain-ment and located as close to the containment as practical.
A simple check valve may not be used as the automatic isola-tion valve, criterion 57 conformance Penetrations X-204 (A through H) for the drywell-to-torus vacuum breaker nitrogen supply and their associated isolation valves conform to the requirements of GDC 57. A normally closed, air-operated globe valve is located in each line outside the containment.
6.2.4.2.3 containment Isolation Dependability Fermi 2 asets the NRC requirements developed for reliable con-tainment isolation as follows :
o ne containment isolation design complies with the recom-sendation of SRP 6.2.4 in that thers is diversity in the parameters sensed for the initiation of containment iso-lation.- Safety-grade signals are provided for the detsc-tion of abnormal conditions in the reactor coolant system and containaants these are low reactor vessel water level and high drywell pressure several lines are not isolated on the high-drywell-pressure signal in order to retain system avnilability for small breaks or leaks. Justification ior these casas is given under Comments in Table 6.2-15 l
6.2-81
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TABLE 6.2-15 ESSENTIAL / NONESSENTIAL LINES (Cont'd)
Containment Containment Penetration Valve toolation Member Byetem/ Lino Number Classification 5ignale* Commente X-43 InfCU/ reactor water (cleanup here fore, toolation on -
from recirculation piping) high drywell pressure- to (Cont'd) not needed.
X-44 Cor 8/ combustible gas con- V4-2143 Essential leone trol system section V4-2153 Essential peone X-47a PCMs/drywe11 VS-2548 Essential leone
- instrumentation X-47b PCMs/drywell VS-2549 Essential none ~ '
instrumentation X-47e Pots /drywe11 pre 4eure VS-2230 Essential leone ]
a X-4de PCMS/ containment atmosphsre V5-2151 Essential mone SErM$d COMTMuMEul _PEufTIEMiod g 7 sample '
AlumB ER
- PC.Rt%" ';
Y X-48b PCMS/ containment atsoephere VS-2152 Essential leone I k N
M sample g $
2
- X-48c Poss/ containment atmosphere V5-2153 Essential leone sample X-48d PCMS/ containment atsoephere v5-2154 Essential leone sample X-48e PCMS/ containment atmosphere V5 2155 Essentist teone sample X-48f PASS / containment drywell V13-7365 leoneesential teormally Administrative control atmosphere sample V13-7375 closed utilized.
X-49a heactor recirculation / V9-3767 Isoneesential B, K High-pressure line with recirculation pump seat V8-3710 Moneesential BK check valves inside and purge outside containment, and an orifice in the line to prevent backflow.
X-51a steactor recirculation / V8-3768 teoneesential 8, K recirculation pump seat V8-3590 Noneesential B, K purge R
9
- " % O TABLE 6.2-15 ESSENTIAL / NONESSENTIAL LINES (Cont'd)
Containment . . Contalsment Penetration valve Isolation System /Line Number CIEaeffleetion, Signale# Commente Number i X-211A RHR/RNR suppression pool V8-2153 Essential A.K l spray V8-2156 Essential A.K i X-2118 RHR/RHR ouppreeston pool ve-2155 Essential AK spray V8-2157 Essential A,K ,
X-212 RCIC turbine exhaust line V11-2002' Essential RF X-213A TWM8 onction' VS-3832 moneesential e,K VS-3834 Isoneseentiat B,K X-213e TwMS discharge VS-3831 peoneesential s,K ve-3833 stoneesential 8. K X-214 HPC1 vacuum breaker line V11-2013 Essential K & X (4) .
V11-2019 Essential K & X (4)
X-214 RCIC wacuum breaker line V11-2020
- Essential K & Y (5) f v11-2026 Essentiat K & Y (5) E u X-215 PcMs return olvision 1 v5-215e Essentist soone SEE . A1.So CoteTMNmenT.
m a w mem re m s- e. -
e X-215 FOCS/combuettble gas v4-2142 Essential Mone $
V4-2156 Essential secne 3
control system eisction X-215 FAss/ containment gaseous V13-7369 stoneesential teormally Administrative control sample return V13-7179 E nessential closed utilised.
X-218 COCS/ combustible gne v4-2140 Essential Isone control system return V4-2148 Essential leone
! v22-2122 Essential leone X-218 V4-2139 Essential leone V4-2149 Essential peone V22-2121 Essential leone X-219 COCS/combuettble gas v4-2141 Essential leone control system suction v4-2155 Essential leone X-219 PCMS return Diviolon II v5-2166 Es,sential leone
- X-220 HPCI turbine exhaust line V11-2OO6 Essential RF X-221 HPCI turbine exhaust drain V11-2008 Essential RF X-222 RCIC vacuum pump discharge V8-2235 Essential . RF
TABLE 6.2-15 ESSENTIAL / NONESSENTIAL LINES (Cont'd)
Containeont Containoent Penetration Valve ,
Isolation i Humber System /Line Humber Claeeffication Signale* Commente X-2278 Core spray pump section V22-201g Essential Isone thermal re11ef X-2278 Core spray pump discharge V22-2016 Essential leone header relief V22-2120 Essential leone X-2275 Core spray pump test VS-2033 Isoneesential A,K X-227s core spray minimum flow VS-2031 Essential Mone .
X-230 PASS /euppreeston pool V13-7367 Isoneesential teorme11y Administrattwo control atmosphere sample V13-7377 teoneesential closed utilised.
X-230 Poes euction Divieics 1 VS-2157 Essential leone .
X-231 Poes euction Diviefon II v5-2165 Essential stone X-231 PASS /euppreeston poot V13-7366 teoneesential teoreally Administrative control
. atmosphere sample V13-7376 stoneesential closed utilised.
. KKWS Prmuy de.d-ment VS-3083 Nocuenhl Skj S a. m pl o SuitiesJ X-48 .-
K d t h w N o ter VS-22.M H.nesse,dM s, oc semp le. 5 o t.ksoha X-48 V4~-30&$ nontssen%l 6, K Sa.mpit ~rLYum X-Zli veiurn ' half
[
E VF-/Z'A t% essenbl 8,, K Sa m p l< j
- We following codes are used to abbreviate teolation signates k
Signal Description Signal Deecription g A peactor Vessel tow-Level 1 3. abeCU Inlet Line High Plow -
5 menctor vessel tow-Level 2 4. Initiation of Standby Liquid C Reactor vesset tow-Level 3 Control D Main Steam Line High Radiation X HPCI System Steam Linee E Main Steam Line High Flow 1. HPCI Space High Temperature F Main Steam Line Wnnel High Temptature 2. High Steam Flow G Hain Steam Line Iow Pressure 3. High Turbine Exhaust Pressure H Torue Pressure > Secondary Ozetainment Pressure 4. MFCI Steam Line Iow Pressure J Iow Condenser Vacuum Y leCIC System Steam Lines K High Drywell Pressure 1. SCIC Space High heperature L High Reactor Vessel Pressure 2. High Turbine Enhaust Pressure H Suction Piping Break 3. High Steam Flow
- 2. Moisture-Sensitive Tape 1 Closes Wrough Electrical Interlocke H High Sump 14 vel or High Sump Temperature with Other System Valves or Pump footore P Turbine Iha11 ding High Temperature I4 locked Closed R peactor Butiding Exhaust stadiation High RF Iteverse Flow W Be#CU System Suction f.ine leH Remote Manual
- 1. InfCU Space High Temperature
,2. ItWCU Space High Dif ferential Waporature BRASS is postaccident sampling systees.
FERM12 0FLUt TABLE 6.2-16 ESSENTI AL/NONESSENTI AL SYSTEMS l System Classification Comments Main steam. Nonessential Not required for shutdown.
MSIV leakage control Essential Not needed for a safe shutdown of the reactor. i However, the system is !
required following a LOCA to provide long-term leaktightness of main steam isolation l valves.
Feedwater Nonessential Not required for shut-down. Portion that is Class 1 is essential.
Reactor core isola- Essential Necessary for core cool-tion cooling down following isola-tion from the turbine condenser and feedwater makeup.
Reactor water Nonessential Not required during and )
cleanup immediately following an accident.
High pressure Essential Saf aty system, coolant injection Core spray Essential Safety system.
Standby liquid Essential Ehould be available as control backup to CRD system.
Drywell floor / Nonessential Not necessary for core equipment drains cooldown.
Torus water Nonessential Not required for reactor management shutdown cooling.
Primary containment Essential Required for postacci- i monitoring system dent monitoring of con-tainment atmosphere hydrogen concentration.
1 i Pe im4, 4 n o tr*1 dwin or Mid m) A b nmenthmderm) Sjolta bne55td imme d ag l 4l(
Ls L L e s d sd
- b o\&l Residual heat removal Heat exchangers Essential Main heat sink during ,
isolation.
6.2-236
FERMl 2 UFSAR
- c. RER shutdown cooling k d. Traversing in-core probe (TIP) system withdrawal.
The second level (L2) isolates the majority of the nuclear pres-sure boundary lines and the primary and secondary containment paths. This is also the level that starts the HPCI and RCIC systems, and it has been selected to be lower than the level change resulting from a void collapse following a scram from full power. Specifically, isolation of the following lines is initiated on Level 2 (Table 6.2-2, signal B):
- a. . Reactor sample lines
- c. Drywell air and nitrogen inlet
- d. Suppression chamber exhaust
- e. Suppression chamber air and nitrogen inlet
- f. Drywell exhaust
- g. Drywell pressure control
- h. Suppression chamber pres'sure control
- 1. Purge to standby gas treatment
- j. Control center heating, ventilation, and air condition-ing (HVAC)
- l. Recirculation pump seal purge
- m. Torus water management.
- n. Primary containment radiation sonitoring.
The final isolation level is Level 1 (L1), which is'approximately 14 in. above the top of the active fuel. This level setting provides automatic isolation for the following lines, which penetrate the primary containment, if they are open (Table 6.2-2, signal A):
- b. RHR test line
- c. Core spray test line ,
- d. Suppression chamber spray
- e. Main steam
- f. Main steam line drains.
7.3-41
FERM12 UF&Mt e
turbine bypass valves open fully. This action causes rapid
( depressurization of the nuclear system. From part-load operating conditions, the rate of decrease of nuclear system saturation temperature could exceed the allowable rate of change of vessel temperature. A rapid depressurization of the RPV while the reactor is near full power could result in undesirable differen-tial pressure across the channels around come fuel bundles of su'fficient magnitude to cause mechanical deformation of channel j walls. Such depressurizations, without preventive action, could !
require thorough vessel analysis or core inspection prior to returning the reactor to power operation. To avoid the time-consuming requirements following a rapid depressurization, the steam pressure at the turbine inlet is monitored. On falling
- below a preselected value with the reactor in the RUN mode, isolation of all four main steam lines and the main steam drain line is initiated.
The low-steam-pressure isolation setting was selected far enough below normal turbine inlet pressures so that spurious isolation is avoided, yet high enough to provide timely detection of a pressure regulator malfunction. Although this isolation function is not required to satisfy any of the safety design bases for this system, this discussion is included here to make the listing of isolation functions complete.
7.3.2.2.7.6 Primary Containment (Drywell) High Pressure l'
i High pressure in the drywell could indicate a breach of the I nuclear system process barrier inside the drywell. The automatic closure of various Class B valves prevents the release of
. significant amounts of radioactive material from the primary con-
! tainment. On detection of a high drywell pressure, the following J, pipelines are isolated:
- a. Drywell equipment drain discharge
- b. Drywell floor drain discharge
! c. TIP tubes
- d. Drywell air and nitrogen inlet
- e. Suppression chamber exhaust valves
- f. Suppression chamber air and nitrogen inlet g Drywell exhaust
- h. Drywell pressure control
- i. Suppression chamber pressure control
- j. Purge to standby gas treatment
- k. Control center HVAC recirculation mode
- 1. Reactor building ventilation system isolation.
- s. Torus water sanagesent.
- n. Primary containment radiation sonitoring.
All I
(9 The primary containment high pressure isolation setting was selected to be as low as possible without inducing spurious isolation trips.
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- Th3 total tino itg froc intsko of pricary atacophoro sacplo loop manifold to tha conitoring instrument sampling point is designed i'
(I to be less than 5 minutes. Within the primary containment radia-tion monitor are particulate and halogen filters to collect integrated samples for subsequent analysis.
Associated with each beta scintillation detector is a logarithmic count rate circuit, power supply unit, and meter readout. A recorder is provided in the main control room for display of radiation level. A flowmeter is provided in the sample line, with- local display of flow rate, and means for actuation of the alarm and annunciator associated with the primary containment radiation monitor on loss of sample flow. .
7.6.1.12.1.2 classification The primary containment hydrogen / oxygen monitor subsystem is seismically and environmentally qualified to meet IEEE 344-1975 and 323-1974. Se radiation monitor has not been qualified envizcamentally or seismically.
7.6 1.12.1.3 Supporting systems Electrical Power ,
i The electrical power required for operation of the primary con-tainment radiation and hydrogen / oxygen monitor subsystems is -
l supplied from the 480-V ESF motor control centers (MCCs) and the ;
120-V ac instrument bus as described in subsection 8.3.1.
Pneumatic Power The sneumatic power required for operation of valves in the sample lines will be pupplied by an uninterruptible air syst hov The. YrumseyConh1e n m eni kn.foon m .ho/kg ra OO h$ h1 1 &on mt h Ms m.
described w.
I n it rwp i*e 6 le. A t a-
&o r i in subsection 9.3.,1.
.9 Sp k 3lh..ahe rsatJ,m v as 7.6.1.12.1.4 Equipment Design fa,q r*3 g,
' Initiating circuite cont::o1 of the primary containment radiation and hydrogen / oxygen monitor subsystems for normal operation, test, and calibration is manual. The hydrogen / oxygen monitor subsystem is normally operated continuously from plant startup to shutdown.
Logic The primary containment radiation monitor subsystem incor trip logic circuits for alarm and annunciator operation. porates A low mode alarm trip is provided to indicate . instrument fallure on 16ss of normal background reading, and a high mode trip to indicate a radiation level exceeding a predetermined normal back-s ground level. We hydrogen / oxygen monitor has alarms as defined -
in Table 7.6-2.
7.6-37
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