fef rw assf sdf sfdsdf fsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsdsd
TRANSCRIPT
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
1/86
Rev. 0
Design Control Document/Tier 2ABWR
List o f Tables........................................................................... ............................................. 10.0-iii
List of Figures ....................................................................... ................................................. 10.0-v
10.0 Steam and Po wer Con version System ................................................................................. 10.1-1
10.1 Summary Description ........................................................................................... 10.1-1
10.1.1 Pro tective Features ........................................................................... ........ 10.1-2
10.2 Turbine Gen erator ............................................................................................... 10.2-1
10.2.1 Design Ba ses........................................................................ ...................... 10.2-1
10.2.2 Description ......................................................................... ....................... 10.2-2
10.2.3 Turbin e In tegrity .............................................................................. ...... 10.2-11
10.2.4 Evalua tion .................... .......................................................................... 10.2-14
10.2.5 CO L License Info rma tion .................................................................. .... 10.2-15
10.2.6 Referen ces....................................................................................... ....... 10.2-16
10.3 Main Steam Supply System ............................................................................. ..... 10.3-110.3.1 Design Ba ses........................................................................ ...................... 10.3-1
10.3.2 Description ......................................................................... ....................... 10.3-2
10.3.3 Evalua tion .......................................................................... ....................... 10.3-3
10.3.4 Inspection an d Testing Requ iremen ts.......... .......................................... 10.3-3
10.3.5 Water Chemistry (P WR) .................................................................... ...... 10.3-3
10.3.6 Steam an d Feedwater System Materia ls .................................................. 10.3-4
10.3.7 CO L License Informa tion .................................................................. ...... 10.3-5
10.4 Oth er Features of Steam and Power Con version System ................................... 10.4-1
10.4.1 Main Co nd enser ....................................................................................... 10.4-1
10.4.2 Main Cond enser Evalua tion System ....................................................... 10.4-6
Chapter 10
Table of Contents
Certrec GE
ABWR
DCD R4
Digitally signed by Certrec GEABWRDCDR4DN:o=VeriSign,Inc., ou=VeriSign
Trust Network,ou=www.verisign.com/repository/RPA Incorp.by Ref.,LIAB.LTD(c)98,ou=Persona NotValidated,ou=Digital IDClass 1-Microsoft Full Service,cn=Certrec GEABWR DCDR4,[email protected]:2007.08.3014:36:04 -05'00'
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
2/86
Rev. 0
Design Control Document/Tier 2ABWR
Table 10.1-1 Summary of Importan t Design Features and P erforma nce Chara cteristics
of th e Steam and Po wer Con version System ....................................................... 10.1-4
Table 10.3-1 Main Steam Supply System Design Da ta ............................................................. 10.3-6
Table 10.4-1 Co nd enser Design Dat a ..................................................................................... 10.4-31
Table 10.4-2 Main Co nd enser Evacua tion System ................................................................. 10.4-31
Table 10.4-3 Circula ting Water System ....................................................................... ............ 10.4-32
Table 10.4-4 Co nd ensate Pur ification System ........................................................................ 10.4-32
Table 10.4-5 Co nd ensate an d Feedwater System Design Data .............................................. 10.4-33
Table 10.4-6 Co nd ensate an d Feedwater System Co mpo nen t Failure Ana lysis...... ............. 10.4-34
Chapter 10
List of Tables
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
3/86
Rev. 0
Design Control Document/Tier 2ABWR
Figure 10.1-1 Referen ce Steam & Po wer Co nversion System ................................................ 10.1-7
Figure 10.1-2 Reference Heat Balance for Guar anteed Reactor Rating ............................... 10.1-8
Figure 10.1-3 Referen ce Hea t Balan ce for Valves-Wide-Open (VWO) ................................. 10.1-8
Figure 10.2-1 Turbin e Stop Valve Closure Characteristic.................................................... 10.2-17
Figure 10.2-2 Turbin e Cont rol Valve Fast Closure Characteristic....................................... 10.2-18
Figure 10.2-3 Acceptable Range for Con trol Valve Norm al Closure Motion ..................... 10.2-19
Figure 10.2-4 Generator Hydrogen and CO2 System........................................................... 10.2-20
Figure 10.3-1 Main Steam Supply System ............................................................................. . 10.3-7
Figure 10.3-2 Main Turbin e System ........................................................................ ............... 10.3-8
Figure 10.4-1 Main Conden ser Evacua tion System .............................................................. 10.4-35
Figure 10.4-2 Turbin e G land Seal System.................................................... ......................... 10.4-36
Figure 10.4-3 Circula ting Water System.. .............................................................................. 10.4-37
Figure 10.4-4 Cond ensate Pur ification System ..................................................................... 10.4-38
Figure 10.4-5 Cond ensate System.................................................. ........................................ 10.4-40
Figure 10.4-6 Feedwater System .............................................................................. .............. 10.4-42
Chapter 10
List of Figures
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
4/86
Rev. 0
Design Control Document/Tier 2ABWR
10.0 Steam and Power Conversion System
10.1 Summary Description
The com ponen ts of the Steam and Po wer Con version ( S&PC ) System are designed to
prod uce electrical power utilizing the steam g enerated by the reactor, con dense the
steam into water, and return the water to the reactor a s heated feed water, with a major
portion of its gaseous, dissolved, a nd particulate impurities removed in ord er to satisfythe reactor water q uality requiremen ts.
The S&PC System includes the ma in steam system, the main tu rbin e generato r system,
main cond enser, conden ser evacuation system, turb ine glan d seal system, turbine
bypass system, extraction steam system, cond ensate clean up system, and the cond ensate
and feed water pumping and heating system. The heat rejected to the main cond enser
is removed by a circulating water system and discharged to the power cycle heat sink.
Steam, genera ted in th e reactor, is supplied to th e high-pressure turbine a nd the steam
moisture separators/reheaters. Steam leaving th e high-pressure turb ine passes throug h
a comb ined mo isture separato r/reheater prior to entering the low pressure turbines.
The mo isture separato r dra ins, steam reh eater dra ins, and the dra ins from th e two high
pressure feedwater h eaters are pumped b ack to the reactor feedwater pump suction by
the h eater dra in pumps. The low pressure feedwater hea ter dra ins are cascaded to th e
condenser.
Steam exhausted from the low-pressure turbines is cond ensed and deaera ted in th e
cond enser. The con densate pumps take suction fro m th e cond enser hotwell and deliver
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
5/86
Rev. 0
Design Control Document/Tier 2ABWR
33% of the rated steam flow is provided to discharge excess steam directly to the
conden ser. Altho ugh the ABWR Stand ard Plan t design is for 33% bypass, this capab ility
could be increased to a full load reject capability without affecting th e Nuclear I sland.
Ind ividual compo nents of the S&PC System a re ba sed o n pr oven co nventiona l designs
suitable for use in large, cen tral station power plan ts.
All auxiliary equipm ent is sized for the maximum calculated unit capability with turbine
valves wide open.
The S&PC System is designed for sustained long-term o pera tion with a h eat input eq ual
to the rated 3919 MWt available from the NSSS when the reactor core is generating its
rated 3926 MW ther mal output. The S&PC System is designed to oper ate at 105% of
maximum gua ranteed turbine thro ttle flow (assumed to correspond to turbine valves
wide open) fo r transients and shor t-term load ing cond itions.
The inlet pressure at the turbine main steam valves will not exceed rated pressure,except when operating abo ve 95% of th e maximum guara nteed turbine flow. It will be
permissible to increase the inlet pressure to 103% of rated pressure, pro vided the
contro l valve position is adjusted so that the r esulting steam flow d oes not exceed the
steam flow th at is obtained when o perating a t rated pressure with contro l valves wide
open.
The n ecessary biological shielding for personn el protection is provided for all rad iation
prod ucing compo nents of th e power conversion system, including th e main turbines,
moisture separato r/reheaters, feedwater hea ters, cond enser and steam jet air ejector.
The reference guaran teed ra ting and valves-wide-open flow qua ntities and fluid en ergy
levels are shown on the turb ine cycle heat balances (Figures 10 1 2 and 10 1 3
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
6/86
Rev. 0
Design Control Document/Tier 2ABWR
10.1.1.2 Overpressure Protection
The fo llowing compon ents are provided with overpressure protection in accord ance
with the ASME Boiler an d P ressure Vessel Code , Section VIII:
(1) Moisture separator/reheater vessels
(2) Selected low pressure feedwater heaters
(3) High pressure feedwater heaters
( 4) H ea ter d ra in ta nk
10.1.1.3 Turbine Overspeed Protection
Turbin e o verspeed pro tection is discussed in Subsection 10.2.2.4.
10.1.1.4 Turbine Integrity
Turbin e in tegrity is discussed in Subsections 10.2.3 an d 3.5.1.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
7/86
Rev. 0
Design Control Document/Tier 2ABWR
Table 10.1-1 Summary of Important Design Features and PerformanceCharacteristics of the Steam and Power Conversion System
Nuclear Steam Supply System, Full Power Operation
Rated reactor core power, MWt 3,926
Rated NSSS power, MWt 3,919
Reactor steam outlet pressure, MPaA 7.17Reactor nominal outlet steam moisture,% 0.1
Reactor inlet feedwater temperature, C 215.6
Turbine-Generator
Nominal Rating, MWe ~1,400
Turbine type Tandem compound, six flow, 132.08 cmlast-stage bucket
1 high pressure turbine
3 low pressure turbines
Operating speed, rad/s 188.5
Turbine throttle steam pressure, MPaA 6.79
Throttle steam nominal moisture,% 0.4
Moisture Separator/Reheaters (MSRs)
N b f MSR i
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
8/86
Rev. 0
Design Control Document/Tier 2ABWR
Design Conditions:
Normal flow, m3/h ~1817.2
Total head, m 426.72
Rated motor power, kW ~3800
Feedwater Heaters
Low Pressure Heaters
a. No. 1
Number per stage 3
Stage pressure, kPaA 24.5
Duty per shell, kW 22.4 x 103
b. No. 2
Number per stage 3
Stage pressure, kPaA 60.8
Duty per shell, kW 48.85
c. No. 3Number per stage 3
Stage pressure, kPaA 147
3
Table 10.1-1 Summary of Important Design Features and PerformanceCharacteristics of the Steam and Power Conversion System (Continued)
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
9/86
Rev. 0
Design Control Document/Tier 2ABWR
Reactor Feedwater Pumps
Number of pumps 3 normally operating (3365%), variablespeed
Pump type Horizontal, centrifugal, single stage
Driver type electric motors
Design conditions:
Main pumps:
Normal flow, m3/h ~4202.27
Total head, m ~640.08
Rated motor power, kW ~11,200
Heater Drain Pumps
Number of pumps 2 x 50%
Pump type Horizontal, centrifugal
Driver type Fixed speed motor
Table 10.1-1 Summary of Important Design Features and PerformanceCharacteristics of the Steam and Power Conversion System (Continued)
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
10/86
Rev.0
DesignControlDocument/Tier2
SummaryDescr
iption
10.1-7
ABWR
Figure 10.1-1 Reference Steam & Power Conversion System
MAIN STEAM
FROM REACTOR
CV
REHEAT STEAM
MS
X Y
6A5A
XY
M
M
M
REACTOR FEED
PUMP
TURBINE
BYPASS
TO
REACTORHEATER DRAIN
TANK
HEATER DRAIN
PUMP
6E 5B
Y X
M
MRECIRC & CLEANUP
TO HOTWELL
SJAE
GSC
OFF-GAS
OFF-GAS
SJAE
CONDENSATE
POLISHERS
CONDENSATE
FILTERS
CONDENSATE
PUMPS
C.W.LP CONDENSER IP CONDENSER
3L 2L
4L 1L
3I 2I
1I4I
3H 2H
1H4H
C.W.
HP CONDENSER
CIV
GEN
LP TURBINELP TURBINELP TURBINE
CIVCIV
MSR A1, A2, B1, B2
MSV
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
11/86
Rev. 0
Design Control Document/Tier 2ABWR
The following figures are located in Chapter 21 :
Figure 10.1-2 Reference Heat Balance for Guaranteed Reactor Rating
Figure 10.1-3 Reference Heat Balance for Valves-Wide-Open (VWO)
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
12/86
Rev. 0
Design Control Document/Tier 2ABWR
10.2 Turbine Generator
10.2.1 Design Bases
10.2.1.1 Safety Design Bases
The turb ine genera tor ( T-G ) d oes not serve no r support an y safety function an d h as no
safety design basis. The turb ine gen erator is, ho wever, a potential source of high energy
missiles tha t could d amage safety-related eq uipmen t or structures. The turbine is
designed to minimize the po ssibility of failure of a turbin e blade o r roto r. Turbine
integrity is discussed in Subsection 10.2.3. The e ffects of poten tial h igh energy missiles
are d iscussed in Cha pter 3. In a dd ition, the main steam turbine stop valves are ana lyzed
to dem onstrate structural integrity under safe shutdown earth q uake (SSE) load ing
conditions.
10.2.1.2 Power Generation Design BasesPower Generation Design Basis OneThe T-G is inten ded for eith er ba se load or load
following operation . The gro ss generato r outputs at reference guaran teed reactor
ratin g an d valves-wide-open (VWO) operation ar e given on th e hea t bala nces sho wn on
Figures 10.1-2 and 10.1-3, respectively.
Power Generation Design Basis TwoThe T-G load change cha racter istics are
compatible with the instrumentation and contro l system which coo rdina tes T-G and
reactor operation.
Power Generation Design Basis ThreeThe T-G is designed to a ccept a sudden loss of
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
13/86
Rev. 0
Design Control Document/Tier 2ABWR
10.2.1.3 Functional Limitations Imposed by the Design or Operational Characteristics ofthe Reactor Coolant System
10.2.1.3.1 Turbine Stop Valve
During a n event resulting in turb ine stop valve fast closure, turbine in let steam flow will
no t be reduced fa ster than tha t sho wn in Figure 10.2-1.
10.2.1.3.2 Turbine Control Valve
During any event resulting in turbine co ntrol valve fast closure, turbine inlet steam flow
will not be reduced faster than that shown in Figure 10.2-2.
The turb ine contro l valve steam flow shutoff rate, upo n a step reduction to zero in
pressure regulation flow deman d ( no resulting bypass steam flow d eman d) , will be
within the region shown in Figure 10.2-3. Any single control system failure or T-G event
will no t cause a faster steam flow reduction th an tha t shown in Figure 10.2-3 witho utinitiating an immediate reactor trip.
The turb ine con trol valves are capable of full stroke opening and closing times no t
greater tha n 7 seconds for ad equa te pressure control perform ance.
10.2.1.3.3 Automatic Load Maneuvering Capability
Within the auto matic load fo llowing region of the po wer/flow operating m ap (Figure
15.0-1), steam flow will auto mat ically respond to a lo ad dem and step as follows:
(1) For positive load dema nd signal changes less than 10% Nuclear Boiler Rated
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
14/86
Rev. 0
Design Control Document/Tier 2ABWR
Moisture separation and reheating of th e high -pressure turbine exhaust steam is
performed by four com bined moisture separato r/reheaters (MSRs). Two MSRs are
located o n each side of the T-G center line. The steam passes through the low-pressure
turbines, each with fo ur extraction points for the four low-pressure stages of feedwater
heating , and exh austs into the ma in conden ser. In ad dition to th e external MSRs, the
turbines are designed to separate water from th e steam an d d rain it to th e next lowest
extraction point feedwater heater.
The genera tor is a d irect dr iven, th ree-pha se, 60 Hz, 188.5 rad /s synchro no us genera tor
with a water-cooled stator an d h ydro gen coo led roto r.
The turb ine-generato r uses a digital mo nitoring and contro l system which, in
coord ination with th e turbine Steam B ypass and Pressure Co ntrol System, contro ls the
turbine speed, load, a nd flow for startup and norm al operation s. The con trol system
operates the turbine stop valves, control valves, and combined intermediate valves
(CIVs). T-G supervisory instrumentation is provided for operational analysis andmalfunction d iagno sis.
Automa tic contro l functions are programm ed to pro tect the Nuclear Steam Supply
System throug h appropriate corrective a ctions (Section 7.7).
T-G a ccessories include th e bear ing lubr ication oil system, electro hydra ulic contro l
(EHC) system, turning gear, hydrogen and CO 2 system, seal o il system, stator co oling
water system, exhaust hood spray system, turbine gland sealing system, and turbinesupervisory instrument (TSI) system.
The T-G unit and associated piping, valves, and controls are located completely within
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
15/86
Rev. 0
Design Control Document/Tier 2ABWR
The m ain stop valves are opera ted in an open-closed mod e either by the emerg ency trip,
fast acting valve for t ripping , or by a sma ll solenoid valve for testing. The d isks are to tally
unba lanced a nd canno t open again st full differential pressure. A bypass is provided to
pressurize the belo w seat a reas of the four valves. Spring s are d esigned to close the main
stop valve in approximately 0.20 second under the emergency conditions listed in
Subsection 10.2.2.5.
Each stop valve contain s a permanen t steam strainer to prevent for eign ma tter from
entering th e contro l valves and turb ine.
The co ntrol valves are designed to en sure tight shutoff. The valves are of sufficient size,
relative to their cracking pressure, to require a pa rtial balan cing. Each contro l valve is
operated by a single actin g, spring-closed servomotor opened by a high pr essure fire-
resistan t fluid supplied th rough a servo valve. The co ntrol valve is designed to close in
approximately 0.20 second.
High-Pressure TurbineThe H P turb ine receives steam th rough four steam leads, one
from each control valve outlet. The steam is expanded axially across several stages of
stationa ry and moving blades. Steam pressure immed iately downstream o f the first stage
is used as a load reference signal for reacto r contro l. Extraction steam from th e turbine
supplies the last stage of feed water heating . H P turb ine exha ust steam is collected in
eight cold rehea t pipes, four at each end of the turb ine. Most of the exh aust steam is
routed to th e MSR inlet, but pa rt of it is diverted a nd supplies the n ext to last stage offeedwater heating.
MoistureSeparator ReheatersFour horizontal cylindrical-shell combined moisture
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
16/86
Rev. 0
Design Control Document/Tier 2ABWR
which share a co mmo n casing. Altho ugh they utilize a common casing, th ese valves ha ve
entirely separate operating mechan isms and contro ls. The fun ction o f th e CI Vs is to
protect the turb ine aga inst overspeed from steam a nd water energy stored between the
main stop an d con trol valves and the CI Vs. On e CIV is located on each side of each LP
turbine.
Steam from the MSRs enters the single inlet of each valve casing, passes through the
permanent basket strainer, past the intercept valve and stop valve disks, and enters theLP turb ine thro ugh a single inlet. The C IVs are located as close to th e LP tur bine as
possible to limit the amo unt o f uncon trolled steam available for overspeeding th e
turbine. U pon loss of load , the intercept valve first closes then th rottles steam to th e LP
turbine, as required to contro l speed and mainta in synchro nization. It is capable of
open ing a gain st full system pressure. The in termedia te stop valves close on ly if the
intercept valves fail to operate properly. These valves are capable of opening against a
pressure d ifferen tial of appro ximate ly 15% of th e maximum expected system pressure.The interm ediate stop valve an d intercept valve are designed to close in approximately
0.2 second .
Low-Pressure TurbinesEach LP turb ine receives steam fro m two C IVs. The steam is
expan ded axially across several stages of stationary and moving buckets. Turbin e stages
are n umbered consecutively, starting with the first HP turbine stage.
Extraction steam from the LP turbines supplies the first four stages of feedwaterheating . A fifth extraction stage ma y be provided to remove moisture an d pro tect the
last-stage buckets from ero sion ind uced by water d rop lets. This extraction is drained
directly to th e cond enser
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
17/86
Rev. 0
Design Control Document/Tier 2ABWR
The ro tor bo dy and shaft is machined from a single, solid steel forging. D etailed
examination s include:
(1) material property checks on test specimens taken from the forging;
(2) photomicrographs for examination of microstructure;
(3) magnetic particle and ultrasonic examination;
(4) surface finish tests of slots for indication o f a stress riser.
Bulk Hydrogen SystemThe bulk hydrogen and CO 2 system is illustrated on
Figure 10.2-4. The hydro gen system is designed to provide th e n ecessary flow a nd
pressure at the main g enerato r for purging carb on d ioxide during startup and supply
makeup hydrogen for generator leakage d uring normal operation.
The system con sists of hydro gen supply piping with all th e n ecessary valves,
instrumenta tion, ga s purity measuring eq uipment, hydrog en ga s dryers, and bulk
hydrogen storage unit.
Fires and explosions during filling and /or purging of the gen erator a re prevented b y
inerting the generator with CO 2 so that a flammable mixture of hydrogen and oxygen
cannot be produced. Unneeded hydrogen is vented outside through a flame arrestor.
The bulk hydrogen system utilizes the guidelines given in EPRI report NP-5283-SR-A
with respect to these portions of th e guidelines involving hydrog en th at d o n ot d eal
specifically with th e H WC system Specifically the bulk hydro gen system piping an d
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
18/86
Rev. 0
Design Control Document/Tier 2ABWR
10.2.2.3 Normal Operation
During n orma l operation, th e main stop valves and CIVs are wide open. O peration o f
the T-G is under th e con trol o f th e Electro-H ydraulic Co ntrol (EH C) System. The EHC
System is comprised of three basic subsystems: the speed control unit, the load control
unit, and the flow control unit. The no rmal function o f the EH C System is to gen erate
the po sition signa ls for the fo ur ma in stop valves, four ma in con tro l valves, and six CIVs.
10.2.2.4 Turbine Overspeed Protection System
In addition to the normal speed control function provided by the turbine control
system, a separate turbine overspeed protection system is included. The turbine
overspeed system is a highly reliable and redundant system which is classified as non-
safety-related.
Pro tection aga inst turbine overspeed is provided b y the mechan ical overspeed trip an d
electrical backup overspeed trip. Redundancy is achieved by using at least two
independ ent cha nn els from the signal source to th e output device. The sensing device,
line and o utput device are of a d ifferent nature for ea ch individual chann el in ord er to
increa se reliability.
The overspeed sensing devices are located in the fro nt bea ring standa rd a nd, th erefore,
are protected fro m the effects of missiles or pipe b reak. The h ydraulic lines are fail-safe;
that is, if on e were to be bro ken, loss of hydraulic pressure would result in a turbine trip.The electric trip signa ls are red und ant. O ne circuit could be disabled by dama ge to the
wiring, but th e other system is fail-safe (i.e., lo ss of signal results in a turbin e trip) . These
f t id inh nt t ti n g in t f il f th d t m d b
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
19/86
Rev. 0
Design Control Document/Tier 2ABWR
(2) Intermediate stop valves/Intercept valves
(3) Primary speed control/Backup speed control
(4) Fast acting solenoid valves/Emergency trip fluid system
(5) Speed control/Overspeed trip/Backup overspeed trip
The m ain stop valves and con tro l valves provide fu ll redun da ncy in tha t these valves are
in series and have completely independ ent opera ting contr ols and operating
mechan isms. Closure of eith er all four stop valves or all four con tro l valves shuts off all
main steam flow to the HP turbine. The combined intermediate stop and intercept
valves are also in series and have completely independ ent o perating contro ls and
operating mechanisms. Closure of either valve or both valves in each of the six sets of
combined intermediate stop a nd intercept valves shuts off a ll MSR outlet steam flow to
the three LP turb ines.
The speed co ntrol un it utilizes at lea st two speed signals. An increase in turbine speed
tend s to close the con tro l valves. Loss of two speed signals will initiate a turbin e trip via
the Emergency Trip System (ETS).
Fast acting solenoid valves initiate fast closure of control valves under load rejection
cond itions that migh t lead to rapid ro tor a cceleration. The ETS initiates fast closure of
the valves whether th e fast-acting solenoid valves work or no t.
If speed control should fail, the overspeed trip devices must close the steam admission
l t t t bi d C t d d d f il f d ig f th
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
20/86
Rev. 0
Design Control Document/Tier 2ABWR
(3) Low condenser vacuum
(4) Low lube oil pressure
(5) LP turbine exhaust hood high temperature
(6) High reactor water level
(7) Thrust bear ing wear
(8) Overspeed (electrical and mechanical)
(9) Manual trip handle on front standard
(10) Loss of stator coolant
(11) Low hydraulic fluid pressure
(12) Any generator trip
(13) Loss of EHC electrical power
(14) Excessive turbine shaft vibration
(15) Loss of two speed signals
All of the a bove trip signals except vibrat ion a nd man ual trips use 2/3 or 2/4 coinciden t
trip logic.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
21/86
Rev. 0
Design Control Document/Tier 2ABWR
(6) Shell temperature
(7) Valve posit ions
(8) Shell and rotor differential expansion
(9) Shaft speed, electrical load, and control valve inlet pressure indication
(10) Hydrogen temperature, pressure, and purity
(11) Stator coolant temperature and conductivity
(12) Stator-winding temperature
(13) Exciter air temperatures
(14) Turbine gland sealing pressure
(15) Gland steam condenser vacuum
(16) Steam chest pressure
(17) Seal oil pressure
10.2.2.7 TestingThe electrical and mechanical overspeed trip devices can be tested remotely at rated
speed, und er load, by means of controls on th e EHC test panel. Operation o f the
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
22/86
Rev. 1
Design Control Document/Tier 2ABWR
(8) Remote t rip solenoids
(9) Lubricat ing oil pumps
(10) Control fluid pumps
10.2.3 Turbine Integrity
10.2.3.1 Materials Selection
Turbin e roto rs an d pa rts are mad e from vacuum melted or vacuum degassed Ni-Cr-Mo-
V alloy steel by processes which minimize flaw occurrence and provide adequate
fracture toug hness. Tramp elements are contro lled to th e lowest practical
concentra tions consistent with goo d scrap selection and melting practice, and
consistent with ob taining a deq uate initial and long-life fracture toughn ess for the
environmen t in which th e parts operate. The turbin e materials have the lowest fracture
appeara nce transition temperatures (FATT) an d highest Cha rpy V-no tch ener gies
ob tainable, o n a co nsistent b asis, from water q uench ed Ni-Cr-Mo-V material at the sizes
an d strength levels used. Since actual levels of FATT and Ch arpy V-no tch energy vary
depend ing upon th e size of the part, an d the location within the part, etc., these
variations are ta ken into account in accepting specific forgings for use in turbines for
nuclear application. The fracture appearance transition temperature (50% FATT), as
ob tained f rom Ch arpy tests perfo rmed in accord an ce with specification ASTM A-370,
will be n o h igher tha n -17.8C fo r low-pressure turb ine d isks. The C ha rpy V-no tchenergy at th e minimum operating temperature o f each low-pressure disk in the
tang ential direction should be at least 81.4 Nm.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
23/86
Rev. 0
Design Control Document/Tier 2ABWR
Turbine opera ting proced ures are employed to preclude brittle fracture at startup by
ensuring that m etal temperatures are (a ) ad equa tely abo ve the FATT, and (b) as
defined abo ve, sufficient to mainta in the fra cture toughn ess to tangen tial stress ratio at
or abo ve 10 . Sufficient warmup time is specified in the turbine operating
instruction to assure tha t tough ness will be adeq uate to prevent brittle fracture dur ing
startup.
10.2.3.3 High Temperature Properties
The operat ing tem pera tures of the h igh-pressure ro tors are below the stress ruptur e
rang e. Therefore, creep-rupture is no t a significant failure m echanism.
Basic stress and creep-rupture d ata are o btained in standa rd labora tory tests at
appropriate temperatures with eq uipment a nd procedures consistent with ASTM
recom men da tion s in Referen ce 10.2-2, Subsection 10.2.6.
10.2.3.4 Turbine Design
The turb ine assembly is designed to withstand n orma l cond itions and anticipated
transients, including those resulting in turbine trip, without loss of structural integrity.
The d esign o f th e turbine assembly meets the following criteria:
(1) Turbine shaft bearings are designed to retain their structural integrity under
norm al operating load s and anticipated tran sients, including th ose leading toturbine trips.
(2) The multitude of natural critical frequencies of the turbine shaft assemblies
m m
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
24/86
Rev. 0
Design Control Document/Tier 2ABWR
10.2.3.5 Preservice Inspection
The preservice procedures and acceptance criteria are as follows:
(1) Forgings are rough machined with minimum stock allowance prior to h eat
treatment.
(2) Each finished m achined rotor is subjected to 100% volumetric (ultrasonic),
and surface visual examinations, using established acceptance criteria. These
criteria a re mo re restrictive tha n those specified for Class 1 compon ents in th e
ASME Boiler and Pressure Vessel Code, Sections III and V, and include the
requiremen t that subsurface sonic ind ications are either removed or
evaluated to en sure that th ey will not gro w to a size which will compromise the
integrity of the unit during its service life.
(3) All finished ma chined surfaces are subjected to a magnetic particle test withno flaw indications permissible.
(4) Each fully bucketed turbine rotor assembly is spin tested at the h ighest
ainticipated speed resulting fro m a loss of loa d.
Add itional preservice inspections include air leakage tests performed to determine that
the hydrogen cooling system is tight before h ydro gen is introd uced into the gen erator
casing. The hydrog en purity is tested in th e genera tor a fter hydrogen has beenintrod uced. The gen erator wind ings and all motors are megg er tested. Vibration tests
are perform ed on all motor-driven eq uipment. H ydro static tests are perform ed on all
l All i ing i t t d f l k M t t d l f t l k
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
25/86
Rev. 0
Design Control Document/Tier 2ABWR
(3) 100% visual examination of couplings and coupling bolts.
The inservice inspection of valves important to overspeed protection includes the
following:
(1) All main stop valves, control valves, extraction no nreturn valves, and CIVs will
be tested un der load . Test contro ls installed on the main contro l room turb ine
pan el permit full stroking o f th e stop valve, con tro l valves, and CIVs. Valveposition ind ication is provided o n th e panel. Some loa d red uction is necessary
before testing main stop an d con trol valves, and CIVs. Extraction no nreturn
valves are tested by equa lizing air pressure across the air cylinder. Movement
of th e valve arm is observed upo n a ction o f the spring closure mechanism.
(2) Main stop valves, control valves, extraction no nreturn valves, and CIVs will be
tested by the CO L applicant in accorda nce with the BWROG turbine
surveillance test pro gram, by closing each valve and observing b y the valve
position indicator that it moves smoothly to a fully closed po sition. C losure o f
each main stop valve, control valve and CIV during test will be verified by
direct observation of the valve mo tion.
Tightness tests of the m ain stop a nd contro l valves are perform ed a t least once
per ma intenan ce cycle by checking th e coastdown characteristics of the
turbine fro m n o loa d with ea ch set of four valves closed a lternately.
(3) All main stop valves, main contro l valves, and C IVs will be inspected on ce
during th e first three refueling or extended m aintena nce shutd owns.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
26/86
Rev. 0
Design Control Document/Tier 2ABWR
The turb ine is designed, constructed, an d inspected to minimize the po ssibility of any
major component failure.
The turbine has a redundant, testable overspeed trip system to minimize the possibility
of a turbine o verspeed event.
Unrestrained stored energy in the extraction steam system ha s been reduced to a n
acceptable minimum by the ad dition o f no nreturn valves in selected extra ction lines.
The T-G equipmen t shielding requiremen ts and th e metho ds of access contro l for a ll
areas of the Turbine Building ensure that the dose criteria specified in 10CFR20 for
operating personnel are not exceeded.
All areas in proximity to T-G equipmen t are zoned according to expected occupancy
times and radiation levels anticipated und er norm al operating con ditions.
Specification of the various radiation zon es in a ccordan ce with expected occupancy is
listed in Chapter 12.
If d eemed n ecessary during unusual occurrences, the o ccupancy times for certain a reas
will be reduced by administrative controls enacted by health physics personnel.
The design b asis operating con centrations of N-16 in the tu rbine cycle are ind icated in
Section 12.2.
The con nection b etween the low-pressure turbine exha ust ho od and the con denser is
made by means of a stainless steel expansion joint
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
27/86
Rev. 0
Design Control Document/Tier 2ABWR
10.2.5.2 Turbine Design Overspeed
The C OL applicant will provide th e basis for th e turbine overspeed a s required b y
Subsection 10.2.3.4(4).
10.2.5.3 Turbine Inservice Test and Inspection
The C OL applicant will provide th e turbine inservice test an d inspection req uirements
as no ted in Subsection 10.2.3.6.
10.2.6 References
10.2-1 J. A. Beg ley and W.A. Log sdo n, Westingho use Scientific Pa per 71-1E7 MSLRF-
P1.
10.2-2 ASTM Section III, Vol 03.01, E139-83 Stand ard P ractice for Cond ucting
Creep, Creep Rupture and Stress Rupture Tests for Metallic Materials.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
28/86
Rev. 0
Design Control Document/Tier 2ABWR
40
60
80
100
TSTEAM
FLOW,PERCENTOFINITIALSTEAMFLOW
ACCEPTABLE REGION
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
29/86
Rev. 0
Design Control Document/Tier 2ABWR
100
80
60
40
TSTEAMFL
OW,PERCENTOFINITIALS
TEAMFLOW
ACCEPTABLE REGION FOR TURBINE CONTROL VALVEFAST CLOSURE RESPONSE
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
30/86
Rev. 0
Design Control Document/Tier 2ABWR
P =
TV =
INITIAL STEAM FLOW,PERCENT NUCLEAR
BOILER RATED
ACTUAL CONTROL
VALVE FULL STROKECLOSURE TIME
SLOWEST
0.025P
TV
(TV 0.5)/100P
T1 =
T2 =
T3 =
R =
(ALL TIME UNITS IN SECONDS)
100 1000T3
(TV 1.5)P
ACCEPTABLE REGION FOR
NORMAL CLOSURE OFTURBINE CONTROL
VALVES
100
R
80
60
40
WA
TTURB
INEINLET(PERCENTOFINITIALSTEAMFLOW)
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
31/86
Rev.0
DesignControlDocument/Tier2
10.2-20
TurbineGenerator
ABWR
Figure 10.2-4 Generator Hydrogen and CO2 System
H2 SEAL OIL UNIT
VACUUM TANK
TO VACUUMPUMP
GASDRYER
FROM
STATORWINDING
COOLINGWATERSYSTEM
LS
F1
FROM CO2 SYSTEM
FA
FLEXIBLE FILLCONNECTION
GASEOUSHYDROGENSTORAGE
CYLINDERS
RUPTUREDISC
GUARDPIPESEAL
TURBINE ROOMOUTSIDE WALL
GUARDPIPESEAL
GENERATORCASING
H2 MANIFOLD
CO2 MANIFOLD
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
32/86
Rev. 0
Design Control Document/Tier 2ABWR
10.3 Main Steam Supply System
The function of the Main Steam Supply System is to convey steam generated in the
reactor to th e turbine plant. This section d iscusses that po rtion of the m ain steam supply
system b ound ed by, but do es not include, the seismic interface restraint, turbine stop
valves an d turb ine b ypass valves. This por tion do es include the steam a uxiliary valve(s).
This portion of the main steam supply system is designated as the turbine main steam
system.
The main steam line pressure relief system, main steamline flow restrictors, main steam-
line isolation valves (MSIVs), and main steam piping from the r eactor n ozzles through
the o utbo ard MSIVs to th e seismic interfa ce restraint are described in Subsections 5.2.2,
5.4.4, 5.4.5, an d 5.4.9, respectively.
10.3.1 Design Bases
10.3.1.1 Safety Design Bases
The Main Steam Supply System is not required to effect o r support safe shutdown o f the
reactor o r to perfo rm in th e operation of rea ctor safety features; however, the supply
system is designed:
(1) To accommodate operational stresses such as internal pressure and dynamic
loads without failures.
(2) To provide a seismically analyzed fission product leakage path to the main
condenser.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
33/86
Rev. 0
Design Control Document/Tier 2ABWR
Main steam piping fro m the seismic interface restraint to the ma in stop, main turbin e
bypass, including the steam auxiliary valves(s) is analyzed to demonstrate structural
integrity und er safe shutdown earth qua ke (SSE) load ing cond itions. Refer to
Subsection 3.2.5.3 for seismic classification for the lines.
10.3.1.2 Power Generation Design Bases
Power Generation Design Basis OneThe system is designed to d eliver steam f rom the
reactor to the turb ine-generato r system fo r a rang e of flows and pressures varying from
warmup to r ated co nd itions. It also provides steam to the reh eaters, the steam jet air
ejectors, the turbine glan d seal system, the offga s system an d th e dea erating section of
the m ain con denser an d th e turbine b ypass system.
10.3.2 Description
10.3.2.1 General Description
The Main Stea m Supply System is illustrated in Figure 10.3-1. The system d esign d ata is
pro vided in Table 10.3-1. The main stea m pipin g con sists of four 700A pipe size
diameter lines from the o utboa rd MSIVs to the m ain turb ine stop valves. The fo ur ma in
steamlines are connected to a head er upstream of th e turbine stop valves to permit
testing of the MSIVs during plant o peration with a minimum loa d red uction. This
head er arran gement is also provided to ensure that th e turbine bypass and other m ain
steam supplies are con nected to operating steamlines and not to idle lines. The m ainsteam pr ocess downstream of the turb ine stop valves is illustrated in Figure 10.3-2.
The d esign pressure an d tem perature o f the main steam piping is 8.62 MPaG and
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
34/86
Rev. 0
Design Control Document/Tier 2ABWR
See Subsection 10.3.7.2 for C OL license informa tion pertaining to allowable MSIV
leakage.
10.3.2.2 Component Description
The Main Steam Supply System lines are mad e of carbon steel and are sized fo r a norm al
steady-state velocity of 45.72 m/s, or less. The lines are designed to permit hydrotesting
following construction and major repairs without a dd ition of tempo rary pipe supports.
10.3.2.3 System Operation
Normal OperationAt low plan t power levels, the Main Stea m System m ay be used to
supply steam to the turbine g land steam seal system. At high plan t power levels, turbin e
gland sealing steam is norm ally supplied from the h igh pressure heater drain tank or
related turbine extraction.
Steam is supplied to the crossaro und steam reh eaters in the T-G system when the T-Gload exceeds appro ximate ly 15% and supply steam pressure is con tro lled by regulatin g
valves in th e 15 to approxima tely 60% load ran ge.
If a la rge, ra pid red uction in T-G load occurs, steam is bypassed d irectly to th e
conden ser via the turb ine bypass system (see Subsection 10.4.4 for a description of th e
turb ine bypass system) .
10.3.3 Evaluation
All componen ts and piping for the m ain steam supply system a re d esigned in
accorda nce with th e cod es and stand ards listed in Section 3.2. This ensures that th e
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
35/86
Rev. 0
Design Control Document/Tier 2ABWR
10.3.6 Steam and Feedwater System Materials
Steam an d feedwater com ponen t ma terials are id entified in Table 5.2-4.
10.3.6.1 Fracture Toughness of Class 2 Components
The fra cture tough ness properties of the ferritic materials of these compon ents will
meet the requirements of NC-2300, Fracture Toughness Requirements for Materials
(Class 2) of ASME Code Section III, as invoked by Regulatory Guide 1.26, QualityG roup Cla ssification an d Sta nd ard s for Water-, Steam -, an d Ra dioactive-Waste-
Con taining Co mpon ents of Nuclear Power Plants. This also includes the portion o f
the m ain steam supply system defin ed in Section 10.3.
10.3.6.2 Materials Selection and Fabrication
The materials specified for use in Class 2 components will conform to Appendix I to
ASME Cod e Section II I, and to Pa rts A, B, an d C o f Section I I of th e Cod e.
Regulatory Guide 1.85, Cod e Case Acceptab ility ASME Section I II Mater ials, describes
acceptable code cases that will be used in co njunction with th e ab ove specifications.
The fo llowing criteria a re applicable to a ll componen ts:
(1) Regulatory Guide 1.71, Welder Qualification for Areas of Limited
Accessibility, provides the following criteria fo r assuring the in tegrity of weldsin loca tion s of restricted d irect physical an d visual accessibility:
(a) The performance qualification should require testing of the welds when
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
36/86
Rev. 0
Design Control Document/Tier 2ABWR
or d emineralized water are an acceptable source of water for final cleaning or
flushing of fin ished surfaces. The o xygen conten t of the water in th ese vented
tanks need not be controlled.
(3) Acceptance criteria for nondestructive examination of tubular products are
given in ASME Code Section III, Paragraphs NC 2550 through 2570.
10.3.7 COL License Information10.3.7.1 Procedures to Avoid Steam Hammer and Discharge Loads
The CO L applicant will provide operating and mainten ance proced ures that include
adeq uate precautions to a void steam ha mmer a nd discharg e loads (Subsection 10.3.3).
10.3.7.2 MSIV Leakage
The CO L applican t will provide the amo unt o f allowab le MSIV leakage fo r review by theNRC ( Subsection 10.3.2).
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
37/86
Rev. 0
Design Control Document/Tier 2ABWR
Table 10.3-1 Main Steam Supply System Design Data
Main Steam Piping
Design flow rate at 6.79 MPaA
and 0.40% moisture, kg/h
~7.71E+06
Number of lines 4
Nominal diameter 700A
Minimum wall thickness, mm 38.1
Design pressure,MPaG 8.62
Design temperature, C 302
Design code ASME III, Class 2
Seismic design Analyzed for SSE design
loads
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
38/86
Rev.0
D
esignControlDocument/Tier2
MainSteamSupp
lySystem
10.3-7
ABWR
Figure 10.3-1 Main Steam Supply System
M
M M
CV CV
CV CV
CV CV
PSV
PSV
FE FE
SUPPRESSION POOL
ACCU
M.A/S
N/S
RPV
CV CV
DRYWELL
MAIN STEAM LINE
MAIN STEAM LINE
MAIN STEAM LINE
MAIN STEAM LINE
NOT IN SCOPE
ABOVE SEATDRAINS TO
CONDENSER
STEAMAUXILIARY
VALVE (S)
TO TURBINE
GLANDSEAL
SYSTEM
TO REHEATER A
TO REHEATER C
TURBINESTOP VALVES
TOM
AIN
TURBINE
TURBINE BYPASS VALVES
TO CONDENSER
TO OFFGAS SYSTEM A
TO STM JET AIR EJECT A
TO OFFGAS SYSTEM B
TO STM JET AIR EJECT B
TO CONDENSER SPARGER
TO REHEATER B
TO REHEATER D
FE FE
DPV
TORCIC
ACCUM. A18
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
39/86
Rev.0
D
esignControlDocument/Tier2
10.3-8
MainSteamSupplySystem
ABWR
Figure 10.3-2 Main Turbine System
MAIN STEAM LINE
MAIN STEAM LINE
MAIN STEAM LINE
MAIN STEAM LINE
TURBINE
STOP VALVES
TURBINE
CONTROL VALVES
HIGH PRESSURE TURBINE
EXHAUSTTO MSR A1
EXHAUSTTO MSR A2
EXHAUSTTO MSR A2
EXHAUST
TO MSR A1
TO SJAE AAND SJAE B
EXHAUSTTO MSR B1
EXHAUST
TO MSR B2
EXHAUSTTO MSR B2
EXHAUSTTO MSR B1
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
40/86
Rev.0
D
esignControlDocument/Tier2
MainSteamSupp
lySystem
10.3-9
ABWR
Figure 10.3-2 Main Turbine System (Continued)
A
CIV CIV CIV
L P TURBINE HL P TURBINE IL P TURBINE J
CIV CIV
MOISTURESEPARATOR
REHEATER A2
MOISTURESEPARATOR
REHEATER B1
MOISTURESEPARATOR
REHEATER B2
MOISTURE SEPARATORREHEATER A2
LCL
TO
CONDENSER
LCW
P2
M
PCW MP1 RSSV
MAIN STEAM
RSWLVPWC
MP2P1
M
MFO
OPERATING VENT
FROM FBW *6A
FROM HP TURBINE
EXHAUST
FROM FBW *5A
MOISTURESEPARATOR
DRAINTANKA1
TO MTR
DRAIN TANK TO FBW *6A
TOCONDENSER
TO
CONDENSER
FROM FBW *6A
FROMFWB
*6A LSW
LCL LCWREHEATERDRAINTANK
A1
FROMFBW
*6A LSW NOMINAL C&I DESIGN,REDUNDANCYNOTSHOWM
FROMHBT LSW
CIV
/10
/10
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
41/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4 Other Features of Steam and Power Conversion System
This section provides discussions of each of the principal design features of the Steam
and Power C onversion System.
10.4.1 Main Condenser
The m ain co nd enser is the steam cycle heat sink. During norm al opera tion, it receives,
cond enses, dea erates and holds up fo r N-16 decay the ma in turbine exhaust steam, a nd
turb ine bypass steam whenever th e turb ine bypass system is opera ted. The ma in
cond enser is also a collection po int for other steam cycle miscellaneo us drains and
vents.
The ma in con denser is utilized a s a heat sink in the initial phase of reactor cooldo wn
during a n ormal plant shutdown.
10.4.1.1 Design Bases
10.4.1.1.1 Safety Design Bases
The ma in cond enser does not serve or support an y safety function an d h as no safety
design basis. It is, however, designed with necessary shielding and controlled access to
protect plant personnel from radiation. In addition, the main condenser hotwell
provides a ho ld-up volume for MSIV fission prod uct leakage. The suppor ts and a nchors
are designed to withstand a safe shutd own earthq uake.
10.4.1.1.2 Power Generation Design Bases
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
42/86
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
43/86
Rev. 0
Design Control Document/Tier 2ABWR
Oth er flows occurring period ically or continuously originate fro m ( 1) the minimum
recirculation flows of the reactor feed pumps, and con densate pumps, (2) feedwater
line startup flushing, (3) turb ine eq uipment clean dra ins, (4) low-point d rains, (5)
deaera ting steam (6) makeup, etc.
During transient cond itions, the cond enser is designed to receive turbine bypass steam
and feedwater hea ter an d d rain ta nk high-level dumps. These drain tanks include th e
moisture separato r an d r eheater d rain ta nks. The con denser is also d esigned to receiverelief valve d ischarges an d any neccesary venting from moisture separato r/reheater
vessels, feedwater heater shells, the gland seal steam header, steam seal regulator, and
various other steam supply lines. Spray pipes and baffles are designed to provide
protection of th e conden ser tubes and compon ents from high energy inputs to the
cond enser. At startup, steam is admitted to th e con denser shell to assist in cond ensate
deaera tion. The cond ensate is pumped fro m the con denser hotwell by the cond ensate
pumps described in Subsection 10.4.7.
Since the main co nden ser opera tes at a vacuum, an y leakage is into th e shell side of th e
main con den ser. Provision is made fo r detection o f circulating water leakage into the
shell side o f the main cond enser. Water leakage is detected b y measuring th e
cond uctivity of sample water extracted b eneath the tub e bun dles. A leak will allow the
circulating water to dra in down th e tube bund les and be collected for sampling.
Sampling meth ods are described in Subsection 9.3.2. Radioactive leakage to the
atmosphere cannot occur.
Air inleakage an d no ncon densable gases, including hydrogen and oxygen gases
contain ed in the turb ine exhaust steam d ue to dissociation of water in th e reactor are
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
44/86
Rev. 0
Design Control Document/Tier 2ABWR
H otwell level controls provide auto matic makeup or rejection of cond ensate to
mainta in a nor mal level in the cond enser hotwells. O n low h otwell water level, the
makeup control valves open a nd a dmit cond ensate to the hotwell from the cond ensate
storag e tank. When the ho twell is broug ht to within norm al operating rang e, the valves
close. O n h igh water level in th e ho twell, the con densate reject control valve open s to
divert conden sate from th e conden sate pump discharge (do wnstream of th e polishers
and auxiliary cond ensers) to the con den sate storage tan k; rejection is stopped when the
hotwell level falls to within normal operating range. The hotwell level signals andcontro ller will be at least triply and d ual redun dan t to assure the availibility of th e
cond ensate pumps.
During th e initial cooling period after plant shutdo wn, the main con denser removes
residual hea t from the rea ctor coolan t system via the turbine bypass system. Ho wever, if
the co nd enser is no t available to receive steam via the tu rbine bypass system, the rea ctor
coolant system can still be safely coo led d own using on ly Nuclear Island systems.
10.4.1.3 Evaluation
During operation , rad ioactive steam, gases, and cond ensate are present in the shells of
the ma in cond enser. The an ticipated inventory of radioa ctive contam inants during
operation and shutdown is discussed in Sections 11.1 and 11.3.
Necessary shielding a nd contro lled access for the m ain con denser are pro vided
(Section s 12.1 an d 12.3).
H ydrog en buildup durin g operation is not expected to occur due to pro visions for
continuo us evacuation o f the main con denser. During shutdown, significant hydrogen
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
45/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4.1.4 Tests and Inspections
Each condenser shell is to receive a field hydrostatic test before initial operation. This
test will consist of filling th e con denser shell with water a nd , at the resulting static head ,
inspecting all tube joints, accessible welds, and surfaces for visible leakage and/or
excessive deflection. Each conden ser water b ox is to receive a field hydrostatic test with
all joints and external surfaces inspected for leakage.
10.4.1.5 Instrumentation Applications
10.4.1.5.1 Hotwell Water Level
The co nd enser ho twell water level is mea sured by at lea st three level transmitters. These
transmitters provide signals to an indicator, a nnun ciator trip units, the plant computer,
and the hotwell level control system. Level is controlled by two sets of modulating
control valves. Each set consists of a normal and an emergency valve.
On e set of valves allows water to flow from th e cond ensate storag e tan k to the co nden ser
hotwell as the level drops below the setpoint. If the level increases above another
setpoint, the second set of valves located o n th e discharg e of th e cond ensate pumps
opens to allow cond ensate to be pumped back to the storag e tank.
10.4.1.5.2 Pressure
Condenser pressure is measured by gauges, pressure switches, and electronic pressuretran sducers. These instruments provide signals to ann uncia tors, trip units, the Turbin e
Con trol System, Recirculation Flow Con trol System a nd the Steam Bypass and Pressure
C l S I dd i i f i d d d d d f l d
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
46/86
Rev. 0
Design Control Document/Tier 2ABWR
Con denser pressure is an input to the Reactor Recirculation System. Recirculation
pump runb ack is initiated upon the trip of a circulating water pump when con denser
pressure is higher than some site specific preset value. Runback is automatically
initiated when req uired to avoid a turbine trip on high con denser pressure.
10.4.1.5.3 Temperature
Temperature is measured in ea ch LP turbine exha ust ho od by temperature contro llers.
The con trollers modulate a contro l valve in th e water spray line pro tecting the exhaust
hoods from overheating.
Circulating water temperatures are monitored upstream and downstream of each
condenser tube bundle and are fed to the plant computer and a main control room
instrumenta tion for use during period ic con denser performan ce evaluations.
10.4.1.5.4 Leakage
Leakage of circulating water into th e cond enser shell is mon itored by the o nline
instrumentation and the process sampling system described in Subsection 9.3.2.
Con ductivity of th e cond ensate is continuo usly mon itored a t selected locations in th e
cond enser. Cond uctivity and sodium are continuo usly mon itored at th e discharge o f
the con densate pumps. High con densate cond uctivity and sodium content, which
indicate a con denser tube leak, are individually alarmed in the ma in contro l room.
10.4.2 Main Condenser Evacuation System
N d bl d f h l b h M i C d
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
47/86
Rev. 0
Design Control Document/Tier 2ABWR
Power Generation Design Basis Two The MCES establishes and m aint ains a vacuum
in the con denser during po wer operation b y the use of steam jet air ejectors, and b y the
mechan ical vacuum pum p dur ing early startup.
10.4.2.2 Description
The MCES (Figure 10.4-1) consists of two 100%-capacity, double stage, steam jet air
ejector (SJAE) units (complete with interconden ser) fo r power plant o peration, a nd a
mechanical vacuum pump for use during startup. The last stage of the SJAE is a
non cond ensing stage.On e SJAE unit is nor mally in operation and the oth er is on
standby.
During th e initial phase of startup, when the d esired rate o f air and gas removal exceeds
the capa city of th e steam jet air ejectors, and nuclear steam pressure is not ad equa te to
operate th e SJAE units, the mecha nical vacuum pump establishes a vacuum in the ma in
cond enser and other parts of the p ower cycle. The d ischarge from the vacuum pump isthen routed to th e Turbine B uilding compa rtment exhaust system, since there is then
little or no effluent rad ioactivity present. Rad iation d etectors in th e Turbine B uilding
compartm ent exhaust system and plant vent alarm in th e main contro l room if
abn orma l radioa ctivity is detected ( Section 7.6). Rad iation mo nitors are provided on
the m ain steamlines which trip th e vacuum pum p if abn orma l radioa ctivity is detected
in the steam being supplied to th e cond enser.
The SJAEs are placed in service to remove the gases from the main condenser after a
pressure of about 0.034 to 0.051 MPa absolute is established in the main condenser by
the m echanical vacuum pump and when sufficient n uclear steam pressure is available.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
48/86
Rev. 0
Design Control Document/Tier 2ABWR
operation of the m echanical vacuum pumps to ensure the flammable limit of hydrogen
will not be rea ched.
The MCES has no safety-related function (Section 3.2) and, thus, failure of the system
will no t comprom ise any safet y-related system or compon ent and will no t prevent safe
reactor shutdown.
Should th e system fa il completely, a g rad ual reduction in con denser vacuum wouldresult from the b uildup of non cond ensable gases. This reduction in vacuum would first
cause a lowering of turb ine cycle efficiency due to the increase in turbine exhaust
pressure. If the MCES remained inoperab le, conden ser pressure would then reach th e
turbine trip setpoint an d a turbine trip would result. The loss of cond enser vacuum
inciden t is discussed in Subsection 15.2.5.
10.4.2.4 Tests and Inspections
Testing a nd inspection o f the system is performed prior to plant o peration in
accorda nce with applicable codes and standard s.
Com ponen ts of the system are continuo usly mon itored durin g operation to ensure
satisfactory performance. Periodic inservice tests and inspections of the evacuation
system are performed in conjunction with the scheduled ma intenan ce outages.
10.4.2.5 Instrumentation ApplicationsLocal an d rem ote ind icating devices for such param eters as pressure, temperature, and
flow indicators are provided a s req uired for m onitor ing the system opera tion. Dilution
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
49/86
Rev. 0
Design Control Document/Tier 2ABWR
temperature, th e switch activates an an nuciator in the ma in contro l room . The vacuum
pump exha ust stream is discharg ed to the Turbine B uilding compartm ent exha ust
system, which pro vides for ra diation mon itoring o f th e system effluents prior to their
release to the m onitor ed vent stack and the atmo sphere.
The vacuum pump is tripped and its discharge valve is closed upon receiving a main
steam high-high rad iation signal.
10.4.3 Turbine Gland Sealing System
The Turbine Gland Sealing System (TGSS) prevents the escape of radioactive steam
from the turb ine shaft/casing pen etrations an d valve stems and prevents air inleakage
through subatmospheric turbine glands.
10.4.3.1 Design Bases
10.4.3.1.1 Safety Design Bases
The TG SS does not serve or support any safety functio n and has no safety design b ases.
10.4.3.1.2 Power Generation Design Bases
Power Generation Design Basis OneThe TG SS is designed to pr event a tmo spheric air
leakage into the turbine casings and to prevent rad ioactive steam leakage o ut of th e
casings of the turbine-generato r.
Power Generation Design Basis TwoThe TG SS returns the con den sed steam to th e
cond enser and exhausts the n onco nden sable gases, via the Turbine Building
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
50/86
Rev. 0
Design Control Document/Tier 2ABWR
seals operate aga inst vacuum, the sealing steam either is drawn into the casing or leaks
outward to a vent a nnulus. At all gland seals, the vent an nulus is maintained at a slight
vacuum a nd also receives air in-leakage fro m the outside. From each vent ann ulus, the
air-steam m ixture is dra wn to the glan d steam con denser.
The seal steam header pressure is regulated automatically by a pressure controller.
During startup an d low load operation , the seal steam is supplied from th e main steam
line or a uxiliary steam hea der . Above approxima tely 50% load , however, sealing steamis nor mally provided from the h eater d rain tan k vent h eader. At all loads, gland sealing
can be a chieved using auxiliary steam so that plan t power operation can be m aintained
without appreciable radioactivity releases even if highly abnormal levels of radioactive
contam inants are present in the process steam, du e to una nticipated fuel failure in the
reactor.
The outer portion of a ll glands of the turbin e and main steam valves is conn ected to th e
gland steam con denser, which is mainta ined at a slight vacuum by the exhauster blower.
During plan t operation , the gland steam cond enser and on e of the two installed 100%
capacity motor-driven blowers are in operat ion . The exhauster blower to th e Turbin e
Building co mpartm ent exha ust system effluent stream is continuo usly mon itored pr ior
to being d ischarged . The glan d steam cond enser is cooled by main con den sate flow.
10.4.3.3 Evaluation
The TG SS is designed to prevent leakage of ra dioactive steam from the m ain turb ineshaft g land s and the valve stems. The h igh-pressure tu rbine shaft seals must
accommo date a rang e of turbine shell pressure from full vacuum to a pproximately
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
51/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4.3.5 Instrumentation Application
10.4.3.5.1 Gland Steam Condenser Exhausters
10.4.3.5.1.1 Pressure
G land steam con denser exhauster suction pressure is continuo usly monitored and
reported to the main con trol room and plant computer. A low vacuum signa l actuates
a main control room annun ciator.
10.4.3.5.1.2 Level
Water levels in the glan d steam cond enser drain leg a re mon itored a nd makeup is
add ed a s required to m aintain loop seal integrity. Abno rmal levels are an nunciated in
the main control room.
10.4.3.5.1.3 Effluent Monitoring
The TGSS effluents are first monitored by a system-dedicated continuous radiation
mon itor installed on the glan d steam conden ser exhauster blower discharge. H igh
mon itor reading s are alarmed in the m ain con trol room . The system effluents are then
discharg ed to the Turbine B uilding compartm ent exha ust system an d th e plant vent
stack, where furth er effluent rad iation mo nitoring is performed . (See Subsection
10.4.10.1 for CO L license infor mation pertaining to th e rad iological ana lysis of the
TG SS effluen ts.)
10.4.3.5.2 Sealing Steam Header
S li t h d i it d d t d t th i t l d
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
52/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4.4.1.2 Power Generation Design Bases
Power Generation Design Basis OneThe TBS h as the capacity to bypass at lea st 33%
of the rated main steam flow to the main condenser.
Power Generation Design Basis TwoThe TBS is designed to b ypass steam to the m ain
condenser during plant startup and to permit a normal man ual cooldown of the
Reactor Co olant System from a hot shutdo wn cond ition to a po int consistent with
initiation of Residual H eat Removal System o peration.
Power Generation Design Basis ThreeThe TBS is designed, in conjunction with the
reacto r systems, to provide for a 40% electrical step-load reduction withou t reacto r trip.
The systems will also a llow a tu rbine trip b ut witho ut lifting the ma in steam safety valves.
10.4.4.2 Description
10.4.4.2.1 General Description
The TBS shown in Figure 10.3-1 (Main Steam System), consists of a three-valve chest
that is conn ected to th e main steamlines upstream o f the turb ine stop valves, and of
three d ump lines that separately conn ect each bypass valve outlet to one cond enser
shell. The system is designed to b ypass at least 33% of the rated main steam flo w directly
to the co nd enser. The system a nd its componen ts are shown in Figures 10.4-9 and 10.4-
10.
The TBS, in co mbin ation with the reactor systems, provides the capab ility to shed 40%
of th e T-G rated load without reactor trip an d without th e operation of safety/relief
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
53/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4.4.2.3 System Operation
The turbine bypass valves are opened by redundant signals received from the Steam
Bypass and Pressure Control System whenever the actual steam pressure exceeds the
preset steam pressure by a small margin. This occurs when the amount of steam
generated by the reactor cann ot b e entirely used b y the turbine. This bypass dema nd
signal causes fluid pressure to be a pplied to the operating cylinder, which o pens the first
of the ind ividua l valves. As the bypass demand increa ses, ad ditiona l bypass valves are
opened , dum ping th e steam to the con denser. The bypass valves are equipped with fa st
acting servo valves to allow rapid opening of bypass valves upon turbine trip or
generator load rejection.
The bypass valves auto mat ically trip closed when ever the vacuum in the ma in con den ser
falls below a preset value. The bypass valves are also closed o n lo ss of electrical po wer or
hydra ulic system pressure. The bypass valve hydrau lic accumula tors have the capability
to stroke the valves at least three times should the hydraulic power unit fail.
When the rea ctor is operating in th e auto matic load -following mod e, a 10% load
reduction can b e accomm od ated without open ing th e bypass valves, an d a 25% load
reduction can b e accomm od ated with momen tary opening of th e bypass valves. These
load ch ang es are accomplished b y chan ge in reactor recirculating flow without an y
control rod motion.
When the plan t is at zero po wer, hot stand by or initial coold own, th e system is operatedman ually by the control roo m opera tor or b y the plant a utoma tion system. The
measured reactor pressure is then compar ed ag ainst, and regulated to , the pressure set
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
54/86
Rev. 0
Design Control Document/Tier 2ABWR
The effects of a ma lfunctio n o f the turbin e bypass system valves and the ef fects of such
a failure on other systems and co mpon ents are evaluated in Cha pter 15.
10.4.4.4 Inspection and Testing Requirements
Befo re the TBS is placed in service, all turbin e bypass valves are t ested for operability.
The steamlines are hydrostatically tested to confirm leaktightness. Pipe weld joints are
inspected by rad iograph y per ASME III , Class 2 requirem ents upstream an d ANSI B31.1
do wnstream of the valve chest. The b ypass valves may be tested while th e un it is in
operation . Period ic inspections are performed on a rota ting ba sis within a preventive
maintenance program in accordance with manufacturers recommendations.
10.4.4.5 Instrumentation Applications
Main steam pressure is redunda ntly measured in the rea ctor d ome by six electronic
pressure tran smitters. Und er no rmal con ditions, a validated narro w range pressure
signal will be used by the Steam Bypass an d Pressure Co ntrol System (SB&PC ). If o ne of
the signals fails, an ann unciator will be activated but th e bypass control an d/or reactor
pressure regulation will be un affected.
Input to the system also includes load dema nd and load r eference signals from the
turb ine speed load con trol system. The SB&PC System uses these three signa ls to
position th e turbine cont rol valves, the bypass valves, an d, ind irectly the rea ctor in ternal
recirculation pump speed. A complete description of the control system is included inChapter 7.
104 5 Circulating Water System
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
55/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4.5.2 Description
10.4.5.2.1 General Description
The C irculating Water System (Figure 10.4-3) con sists of the following compon ents: (1)
screen ho use and intake screens, pumps, (2) cond enser water bo xes and piping and
valves, (3) tube side of the ma in con denser, (4) water bo x fill and drain subsystem, an d
(5) related support facilities such as for system water treatment, inventory blowdown
and general maintenance.
The po wer cycle heat sink is designed to ma intain th e temperature o f the water en tering
the CWS within th e rang e of 0C to 37.78C. The CWS is designed to deliver water to
the main con denser within a tempera ture range o f 4.45C to 37.78C. The 4.45C
minimum tempera ture is mainta ined, when n eeded, by warm water recirculation.
The cooling water is circulated by at least three fixed speed motor-driven pumps.
The pumps are arranged in parallel and discharge into a comm on h eader. The
discharg e of each pump is fitted with a butterfly valve. This arrang ement permits
isolation and maintenance of any one pump while the others remain in operation.
The C WS and cond enser is designed to permit isolation of ea ch set of the three series
conn ected tube bund les to permit repair of leaks and cleaning of water bo xes while
operating at reduced power.
The CWS includes water b ox vents to h elp fill the cond enser water bo xes during startup
and removes accumulated air and other ga ses from th e water boxes during n orma l
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
56/86
Rev. 0
Design Control Document/Tier 2ABWR
The circulating water pumps are tripped and the pum p an d co nden ser isolation valves
are closed in the event of a system isolation signal from the co nd enser pit high-high
level switches. A conden ser pit high level alarm is provided in the con tro l room. The pit
water level trip is set high enoug h to prevent ina dvertent plan t trips from un related
failures, such as a sump o verflow.
Drain ing o f an y set of series conn ected con denser water bo xes is initiated by closing th e
associated con denser isolation valves and opening th e drain con nection an d water boxvent valve. When the suction standpipe of th e con denser dr ain pum p is filled, the pump
is manua lly started . A low level switch is provided in th e stand pipe, on the suction side
of th e dra in pump. This switch will autom atically stop the pump in the event o f low
water level in the standpipe to protect the pump from excessive cavitation.
10.4.5.3 Evaluation
The CWS is not a safet y-related system; however, a flooding a na lysis of th e Turbin eBuilding is performed o n th e CWS, postulating a co mplete rupture of a single
expansion joint. The analysis assumes that the flow into the condenser pit comes from
both the upstream an d d ownstream side o f the b reak and , for con servatism, it assumes
tha t on e system isolat ion valve do es not fu lly close.
Based on the above conservative assumptions, the CWS and related facilities are
designed such th at the selected com bination of plant physical arrangem ent an d system
protective features ensures that all credible potential circulating water spills inside theTurbine B uilding rema in confin ed inside the co nd enser pit. Further, plan t safety is
ensured in case of multiple CWS failures or other negligible probability CWS related
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
57/86
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
58/86
Rev. 0
Design Control Document/Tier 2ABWR
10.4.5.7 Portions of the CWS Outside of Scope of ABWR Standard Plant
The po rtion outside the ABWR Stand ard Plan t includes:
screen h ouse and intake screens; pumps and pump d ischarge valves; an d
related support facilities such as makeup water, system water treatment,
inventory blowdown, and general maintenance.
10.4.5.7.1 Safety Design Basis (Interface Requirements)
None
10.4.5.7.2 Power Generation Design Basis (Interface Requirements)
The C OL applicant shall provide the following system d esign featur es and a dd itional
information which are site dependent;
(1) Compatible design as described in Subsection 10.4.5.2.
(2) Evaluation per Subsection 10.4.5.2.
(3) Tests and Inspections per Subsection 10.4.5.4.
(4) Instrument applications per Subsection 10.4.5.5.
(5) Flood protection per Subsection 10.4.5.6.
10.4.5.8 Power Cycle Heat Sink (Conceptual Design)
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
59/86
Rev. 0
Design Control Document/Tier 2ABWR
(3) Tests and inspections per Subsection 10.4.5.4.
(4) Instrument applications per Subsection 10.4.5.5.
(5) Flood protection per Subsection 10.4.5.6.
(6) The power cycle heat sink must provide for coo ling of Turbine Service Water
System while the plant is operating on the Co mbustion Turbine G enerato r in
the a bsence of offsite power.
10.4.6 Condensate Purification System
The Co nd ensate Purification System (C PS) purifies and treats the cond ensate as
required to ma intain rea ctor feedwater purity, using filtration to remove suspend ed
solids, including corro sion prod ucts, ion exchang e to remove dissolved solids from
cond enser leakage and o ther impurities, and water treatm ent ad ditions to minimize
corrosion/erosion prod uct releases in th e po wer cycle.
10.4.6.1 Design Bases
10.4.6.1.1 Safety Design Bases
The CPS does not serve or support any safety function and has no safety design bases.
10.4.6.1.2 Power Generation Design Bases
Power Generation Design Basis OneThe CP S cont inuo usly remo ves dissolved an d
suspend ed solids from the con densate to ma intain reactor feedwater q uality.
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
60/86
Rev. 0
Design Control Document/Tier 2ABWR
Power Generation Design Basis SixThe CP S maintains the cond ensate storag e tank
water qua lity as required fo r cond ensate makeup and miscellaneo us cond ensate supply
services.
Power Generation Design Basis SevenThe CPS flow con tro llers an d sequences will be
at least dual redun dan t an d th e vessel flow signals and b ypass arran ged such that the
cond ensate system flow will be uninterrupted even in th e presence of a single failure.
10.4.6.2 System Description
10.4.6.2.1 General Description
The C on den sate Pur ification System (Figure 10.4-4) con sists of a t least three high
efficiency filters arran ged in pa rallel and opera ted in con junction with a no rmally
closed filter bypass. The CPS also includes at least six bead resin, mixed bed ion
exchange demineralizer vessels arranged in parallel with, normally at least five in
operation and one in standby. A strainer is installed do wnstream o f each d emineralizervessel to preclude gross resin leakage into the power cycle in ca se of vessel und erdrain
failure, and to ca tch resin fine leakage as much as possible. The d esign b asis for the CPS
system will be to ach ieve the water q uality effluent cond itions defined in the G E water
qua lity specification. The C PS compo nents are located in the Turbine B uilding.
Pro visions are included to permit air scrub cleaning and replacement of th e ion
excha nge resin. Each o f the demineralizer vessels ha s fail-open inlet and outlet isolat ion
valves which are remotely contr olled from the local CP S control pan el.
A dem inera lizer system b ypass valve is also provided which is man ually or automat ically
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
61/86
Rev. 0
Design Control Document/Tier 2ABWR
operation full load steady-state design flowrate is 2.52L/s of bed. Maximum flowrates
are 3.15 an d 3.79L/s for steady state a nd transient operatio n, respectively. The n ominal
bed dep th is 102 cm.
10.4.6.2.3 System Operation
The CPS is continuously operated to maintain feedwater purity levels.
Full condensate flow is passed through at least three filters and at least five of the sixdem inera lizers, which are piped in para llel. The last deminera lizer is on stan dby or is in
the pro cess of being cleaned , emptied o r refilled. The service run of each d emineralizer
is terminated by either high differential pressure acro ss the vessel or high effluent
cond uctivity or sodium con tent. Alarms for each o f these parameters are provided on
the local control panel and the main control room.
The service run for each filter is terminated by high differential pressure across the
filter. Alarms are provided on the local con trol pan el.
The local contr ol panel is equipped with the a ppropriate instruments and contro ls to
allow the operators to perform the fo llowing operation s:
(1) Remove a saturated filter from service, temporarily allowing some condensate
filter bypass. Clean up the isolated filter by backwashing and place it back in
operation.
(2) Remove an exhausted demineralizer from service and replace it with a standby
unit
-
7/30/2019 FEF RW ASSF SDF SFDSDF FSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSDSD
62/86
Rev. 0
Design Control Document/Tier 2ABWR
when the required minimum rinse has been completed and normal clean bed
conductivity is obtained.
A filter with h igh d ifferen tial pressure is remo ved fr om service and the filter system
bypass valve is opened to maintain condensate flow. The filter is backwashed, refilled
an d return ed to service. The filter system bypass valve is then closed.
Throug h no rmal cond ensate makeup and reject, the conden sate storag e tank water
inventory is processed th rough the C PS, and tank water qua lity is mainta ined as
required for con densate ma keup to th e cycle and miscellaneo us cond ensate supply
services.
The condensate purification and related support system wastes are processed by the
radwaste system, as described in Chapter 11.
10.4.6.3 EvaluationThe CPS does not serve or support any safety function and has no safety design bases.
The Con densate Purification System removes cond ensate system corrosion prod ucts,
and