ML050630082
| ML050630082 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 01/25/2005 |
| From: | National Academy for Nuclear Training |
| To: | Emch R NRC/NRR/DRIP/RLEP |
| Emch R, NRR/DRIP/RLEP, 415-1590 | |
| References | |
| BSEP-0014, SD-29, Rev 2 | |
| Download: ML050630082 (85) | |
Text
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Uf)en CAROLINA POWER & LIGHT COMPANY BRUNSWICK TRAINING SECTION SYSTEM DESCRIPTION SD-29 CIRCULA TING WA TER SYSTEM REVISION 2 Subject Matter Expert Concurrence By Date Date Date Ops Traininq Suoervisor SD-29 I
Rev. 2 Page 1 of 85 l
REVISION
SUMMARY
Revision 2 of SD-29 incorporates the following changes:
- 1. Incorporated changes from ESR 98-0096, Supervisory System; APP (1-UA-5)
Window 2-1 from ESR 99-00359, Setpoints; ESR 99-00185 Level Glasses for CW Waterboxes.
LIST OF EFFECTIVE PAGES 1-85 Revision 2
l SD-29 I
Rev. 2 I
.Page 2 of 85
TABLE OF CONTENTS SECTION PAGE
1.0 INTRODUCTION
. 7 1.1 System Purpose............
7 1.1.1 Tube Sheet Pressurization Subsystem................................................
7 1.1.2 Condenser Water Box Cathodic Protection Subsystem....................... 7 1.1.3 AMERTAP Tube Cleaning Subsystem................................................
7 1.1.4 Condenser Water Box Air Removal Subsystem................................... 8 1.2 System Design Basis...................................................
8 1.2.1 Circulating Water System...................................................
8 1.2.2 Circulating Water Intake and Discharge Canals................................... 8 1.2.3 Circulating Water Intake Structure...................................................
9 1.2.4 Turbine Building Internal Flooding Protection....................................... 9 1.3 General System Description.
10 1.3.1 Circulating Water System..................................................
10 2.0 COMPONENT DESCRIPTION/DESIGN DATA...........................................
- 10 2.1 Intake Canal and Intake Structure (Figure 29-6).
11 2.1.1 Circulating Water Intake Pumps (CWIPs).12 2.1.2.
Debris Filters (Figure 29-2)..................
13 2.1.3 Condenser Water Boxes.13 2.1.4 Discharge Tunnel and Canal.14 2.1.5 Discharge Structure (Figure 29-8).14 2.1.6 Circulating Water Ocean Discharge Pumps (CWODs).15 2.2 Tubesheet Pressurization (TSP) Subsystem.....................
15 2.2.1 Instrumentation.16 2.2.2 Filters.17 2.2.3 Valves.17 2.2.4 Support Rack
................ 18 2.2.5 Local Annunciator Panel.18 2.3 Condenser Water Box Cathodic Protection Subsystem..............
18 2.3.1 Rectifier.20 2.3.2 Anodes.21 2.3.3 Terminal Boxes.21 2.3.4 Junction Boxes.21 2.3.5 Negative Connections.22 2.3.6 Reference Electrodes................
22 2.3.7 Alternate Current Power.22 2.3.8 Direct Current Meters.22 2.4 AMERTAP Condenser Tube Cleaning Subsystem (Figure 29-3 and 29-4)... 23 2.5 Condenser Water Box Air Removal Subsystem............................................ 25 2.6 Turbine Building Condenser Pits.26 SD-29 Rev. 2 Page3 of 85
TABLE OF CONTENTS SECTION PAGE 2.7 System and Component Design Parameters
............................... 27 2.7.1 System Parameters.27 2.7.2 Component Design Parameters.27 2.7.3 Circulating Water Discharge Pump.28 2.7.4 Circulating Water Discharge Pump Motor.29 2.7.5 Circulating Water System Parameter.29 3.0 INSTRUMENTATION AND CONTROLS
.29 3.1 Circulating Water System Control
.29 3.2 Component Control 30 3.2.1 Circulating Water Intake Pump Control.30 3.2.2 Condenser Isolation Valve Control.31 3.2.3 Circulating Water Ocean Discharge Pump Control.32 3.2.4 Circulating Water Discharge Pump Lube Water Pump Control.
33 3.2.5 Supervisory System.33 3.2.6 Debris Filter Backwashing (Figure 29-2).36 3.2.7 Temperature Indications.37 3.2.8 Flow Minimization Schedule 38 3.3 Tube Sheet Pressurization Subsystem Control............................................. 38 3.3.1 Control.................................................
38 3.3.2 Instrumentation.................................................
38 3.4 Cathodic Protection Subsystem
................................................. 39 3.4.1 Control
................................................. 39 3.4.2 Instrumentation.................................................
39 3.4.3 Dual Light Alarm.................................................
39 3.5 AMERTAP Condenser Tube Cleaning Subsystem Control 40 3.5.1 Manual Control
......... 40 3.5.2 Automatic Control.................................................
40 3.6 Condenser Water Box Air Removal Subsystem Control............................... 40 3.6.1 Control.................................................
40 3.6.2 Instrumentation.................................................
41 3.7 Power Supplies.................................................
42 3.8 Monitoring Instrumentation 42 3.8.1 Instrumentation.................................................
42 3.8.2 Annunciators.................................................
43 3.8.3 Process Computer Interface..........................
....................... 43 3.9 Instrument and Control Setpoints 44 4.0 SYSTEM OPERATION................................................. 45 4.1 Normal Operational Relationships.......................
.......................... 45 4.2 Abnormal Operation................................................. 46 4.3 Interrelationships With Other Systems.50 SD-29 Rev. 2 Page 4 of 85 l
TABLE OF CONTENTS SECTION PAGE 5.0 RELATED INDUSTRY EVENTS 51 5.1 PS 3923, Manual Reactor Scram Due to Loss of Condenser Vacuum During Unit Startup.51 5.2 OE 2846, Circ Water Pump Trip Event.51 5.3 SER 7-96, Condenser Tube Failure.52 5.4 SER 8-96, Icing of Traveling Screens and Trash Racks.52 5.5 SOER 85-5, Internal Flooding of Power Plant Buildings.53 5.6 CR 99-01661, Low Vacuum Trip Due to Fouling of Traveling Screens.
53
6.0 REFERENCES
54 6.1 Technical Specifications.s 54 6.2 Updated Final Safety Analysis Report.54 6.3 Piping & Instrumentation Drawings.......................
55 6.4 Control Wiring Diagrams.58 6.5 Modification Packages.59 6.6 Procedures.59 6.7 Miscellaneous.61 7.0 TABLES........
61 29-1 National Pollutant Discharge Elimination System Restrictions for Circulating Water System Operation.62 29-2 Power Supplies.63 29-3.1 Monitoring Instrumentation.......................
65 29-3.2 Supervisory System Monitoring.68 29-4 Annunciators.69 29-5 Instrument and Control Setpoints.70 FIGURES 29-1 Circulating Water System (Unit 2).75 29-2 Debris Filter Cross Section.76 29-3 AMERTAP System Cross Section.77 29-4 AMERTAP System (Unit 2).78 SD-29 I
Rev. 2 Page 5 of 85.
SECTION FIGURES 29-5 29-6 29-7 29-8 29-9 29-10 29-11 TABLE OF CONTENTS PAGE AMERTAP Ball Collection Strainer......................................
.79 Intake Canal General Arrangement..........
............................ 80 Discharge Canal General Arrangement......................................
81 Caswell Beach Pumping Station Layout.............
......................... 82 Caswell Beach Pumping Station CWOD Pump Detail.............................. 83 CWIP Characteristic Pump Curve..................................... 84 CWOD Pump Characteristic Pump Curve..............................
85 SD-29 Rev. 2-Page 6 of 85
1.0 INTRODUCTION
1.1 System Purpose The purpose of the Circulating Water System is to provide the heat sink necessary to remove the latent heat of condensation from the low pressure turbines exhaust steam and to cool this condensate sufficiently to prevent cavitation in the condensate system, thus maintaining the vacuum required for operation. The system also provides dilution flow necessary for acceptable radioactive liquid effluent release concentrations.
1.1.1 Tube Sheet Pressurization Subsystem The purpose of the Tube Sheet Pressurization (TSP) Subsystem is to provide an uninterrupted supply of condensate quality water to the -
integrally-grooved tube sheet (IGTS) cavity at approximately 15 psi above condenser water box pressure at all times during condenser and/or Circulating Water System operation. In addition, the system will monitor leakage and provide a method to determine the location and rate of leaks.
1.1.2 Condenser Water Box Cathodic Protection Subsystem The purpose of the Condenser Water Box Cathodic Protection Subsystem is to provide corrosion protection to each condenser water box and tube sheet.
The system impresses electrical direct current to the metallic structure in sufficient quantity to counteract the effects of galvanic corrosion.
m LI 0 ani T
e CieanngSubsystem s to provide cont s
condenser tubes to maximize heattrAnsfer~ efficiency.
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2 Page 7 of 85 l
1.1.4 Condenser Water Box Air Removal Subsystem The purpose of the condenser water box air removal subsystem is to establish and maintain prime on the circulating water system at the main condenser water boxes. Local level indications for each inlet side condenser water box are provided for operator reference. Portions of this subsystem are common to both Units 1 and 2.
1.2 System Design Basis 1.2.1 Circulating Water System The design basis of the condenser circulating water system are as follows:
flogMo main co n
en y
10 mremo e eat
- 2.
T p
ek praely at Mr ntion resulting from the M
x~riane.
- 3.
The head developed by the pumps can overcome the system friction and provide the static lift required by the syphon seal.
- 4.
The pumps are rated to permit operation of Unit 2 turbine-generator at full 105 percent steam dump conditions without a trip.
- 5.
Complete outage of the condenser circulating water system will not result in loss of any service essential to reactor safety. Therefore, the condenser circulating water system pumps and valves are designed to Seismic Class II requirements.
1.2.2 Circulating Water Intake and Discharge Canals ap 11tir*ows
-,Marsh-area and dia WU200th offshore.
_6 ft/sec and In,
,tihe~x,œsmarg~er'canawp,,
~ate,~sfc.
SD-29 I
Rev. 2 Page 8 of 85
- 2.
qWpe-requirement of
- Me9Onp,
`
IfIt;
- however, the -;l ael-eQtreakevcana14s--appmoximately b c Tunits in of f
s The hydraulic gradient for the Circulating Water System is shown on drawing F-2019.
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1.2.3 Circulating Water Intake Structure
- 1.
The circulating water intake structure was designed to meet seismic Class II criteria and soil pressure loadings.
- 2.
The walls between the pump bays were designed to allow dewatering one bay. The discharge chambers were designed for normal loading plus internal water pressure. The safety factors for the circulating water intake structure against overturning, flotation, and sliding were determined using Class I loading criteria because of its close proximity to the Class I service water intake structure. This design will assure that the circulating water intake structure will not affect the stability of the service water intake structure.
1.2.4 Turbine Building Internal Flooding Protection
- 1.
Flood level alarms in the circulation water condenser pits warn the operator that an abnormal condition exists and that water is entering the pit. Also, a set of three level alarms (one in each pit) installed 108 inches above the pit floors will, when activated, automatically shut off the circulating water intake pumps if a confirmed level of 60 inches has already been received for the affected pit.
SD-29 Rev. 2 l
- Page 9 of 85
1.3 General System Description 1.3.1 Circulating Water System (Figure 29-1)
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=
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- ture,
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.Ming.
Only the intake canal, intake structure, portions of the condenser water box air removal subsystem, discharge canal, and discharge structure are common to both units.
2.0 COMPONENT DESCRIPTION/DESIGN DATA
- a 6wearRiver ture.ture 4arnlike,st ructure). is located at thle gh1I e'canaI m 7 iare a
ili eaf4hef1avoeli-g'screens, at e
- 1take pumps.
Ailed j
the r
u e
-_s twti~riEea=ems~at the mqu make. The turtle blocker panels will allow for maintenance on the structure screen as well as prevent turtles from entering the intake canal. The four circulating water intake pumps for each unit take suction on the intake structure pump bays behind the traveling screens and discharge through the pump discharge valves into the unit's diverting zone. The diverting zone is a common mixing zone which enables any combination of the four pumps to be used.
is Q
nle-JbA
-§hzones (2 per unit). T~Pe-citing 4T61 R fi ii o
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-f ~haaders Land h~eade w
aiso~ation valves to thAjjilldie iandn1.etbra b
waterboxespTiolronentering the.
ce~bs SD-29 Rev. 2 Page 10 of 85 l
NOTE:
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6" te96 ii6t ~-qBn'p &l NOTE:
Since the installation of the AMERTAP condenser tube cleaning system, the backwash zone is no longer used for condenser backwashing. The zone discharge valves are disabled.
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_iency ri&
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A ndenser outlet valve weir. DR6whseam of the u
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7 taatthrouh non pipes Circulating water discharge pumps located at the Caswell Beach pumping station take a suction on the stilling basin and pump the water 2000 ft. beyond the shoreline and release it to the Atlantic Ocean. There are two ocean discharge pipes, one for Unit 1's circulating water discharge pumps and the other for Unit 2's.
The system is filled after maintenance by conventional service water.
2.1 Intake Canal and Intake Structure (Figure 29-6)
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The e nra
-IVWsWeW iftfadiVe rsidfsvfustu re preventing.th ep'sage of lai,,gc1brisfifsnd fish. The pani1i
§1/2U~a-di tn 6' of t2 S 7ti: 6fi ji6fhwest to itheirfland. Froth etawhestadthreiVe anthV-sou s t tfdrrninatingfi'at'ir'the'intake structure. 1leT Tn T
6eaie isI i i
d to a c bh i
q6qF pfI fqirem csfsperu 1it tebpect to minimum >inh imum tide.t nditions.
SD-29 Rev.2 Page 11 of 85l
floc eb n ae eus sh racks arans int1an e
T
_ neof the sapy.
When necessary, these racks may be removed by the in-place crane for cleaning.
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'al l g the system. Th rb h fine my
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e traveling screens are a f
eq pe Ith fish mWm b
g
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The traveling screens are technically part of the Screenwash System and are described in further detail in OSD-29.1.
The Circulating Water Intake Traveling Screens are powered as follows:
1(2) A,B,C & D:
480 VAC 1(2)SA The circulating water intake pumps are also mounted on the intake structure.
2.1.1 Circulating Water Intake Pumps (CWIPs)
The Circulating Water System has four vertical centrifugal, mixed flow, CWIPs per unit.
The pumps are arranged in parallel, each taking suction from its respective pump bay through a traveling screen. The conventional service water header provides lubricating water to the pumps through 1 (2)SW-V36 and 37, individual strainers and cyclone separators. The CWIP induction type motors are equipped with integral bearing oil coolers.
SD-29 I
Rev. 2 I
Page 12 of 85
The CWIPs are powered as follows:
1(2) A and C: 4160 kV Bus 1(2)C 1(2)BandD: 4160kVBus1(2)D Characteristic pump curves for the CWIPs are included as Figure 29-10.
In addition, four Unit 1 vacuum relief valves and four Unit 2 vacuum relief valves are installed on the piping adjacent to the Circulating Water pumps.
These valves serve to break the vacuum developed in the header between the pumps and the condenser waterboxes in the event of a simultaneous trip of all circulating water pumps, eliminating the possibility of water hammer.
2.1.2 Debris Filters (Figure 29-2) sls er. Each debris filter consists of a rubber-lined carbon steelody and a cylindrical, perforated stainless steel screen.
Circulating water enters the filter radially and passes through the cylindrical screen. The water makes a 90o directional change and exits the filter assembly leaving debris on the outside of the cylindrical screen. The debris filters have differential pressure indication on the Control Room XU-2 panel, and locally adjacent to the TSP panel on Turbine Building 20' elevation.
The debris filters are backwashed on line as described in Section 3.2.6.
2.1.3 Condenser Water Boxes
. The Tubesheet pressuriatioh Subsystem and the Condenser Water Box Cathodic Protection Subsystem are described in detail in Sections 2.2. and 2.3 respectively. T ereae lotalof.eight waterboxesperijtiwoinIitand o$n st 1 e
_ss--
SD-29 I
Rev. 2 Page 13 of 85l
The elevation of the upper tubes in the main condenser is higher than the full flow system head of the CWIPs. In the past the circulating water system has been operated with the inlet water boxes vented and the condenser outlet valves throttled to maintain the condensers as full as possible. When operating with the mode selector switch in the C and D positions (condenser outlet valves throttled positions 34% and 85% open respectively) air binding has been experienced adversely affecting overall plant operation. A Condenser Water Box Air Removal Subsystem establishes and maintains a prime at the high point of the circulating water system. This subsystem is described in detail in Section 2.5. To protect against condenser tube leaks from steam or debris impingement, the top three rows of condenser tubes in each inlet and outlet water box have been permanently plugged.
2.1.4 Discharge Tunnel and Canal (Figure 29-7) w~Ts6'air. T e ai~
=X~',t,.Jng.
To=
Thaa
_ t 2.1.5 Discharge Structure (Figure 29-8)
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tructure. Larg e Iiered by
- verti_,
f the structure.
Traveling ltering of the wak
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~
din the da e
eight ci rc rt ur re.
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Page 14 of 85l
2.1.6 Circulating Water Ocean Discharge Pumps (CWODs)
(Figure 29-9)
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to disam fl u
e n
et.
Th On from diluti 4
aal The CWOD Pumps are water cooled and lubricated. Cooling and lubrication water are supplied by two bearing lube water pumps per unit, each taking suction from the bay area via a suction strainer. The pumps discharge the water to the CWOD Pumps for cooling and lubrication.
Backwashing is performed to flush the lube water suction strainers and the CWOD Pumps motor cooling coils. Caution must be taken during these backwashes to slowly open the drain valves. Rapid opening of the valves can cause a low lube water pressure to be sensed and tripping of the CWOD may follow.
The CWOD Pumps are powered as follows:
1(2) A and B: Caswell Beach 4 kV Bus B 1(2) C and D: Caswell Beach 4 kV Bus A Characteristic pump curves for the CWOD Pumps are included as Figure 29-1 1.
2.2 Tubesheet Pressurization (TSP) Subsystem The purpose of the TSP subsystem is to provide indication of a tube to tubesheet leak on either side of the tubesheet and to ensure that leakage to the condenser side is clean demineralized water verses circulating water. The TSP subsystem provides demineralized water at a controlled pressure of 10 to 25 psig above water box pressure and at a monitored flow rate to the space between the tubesheets called the Integrally Grooved Tubesheet (IGTS) cavity. The connection to the Demineralized Water System is fitted with an isolation valve and double check valve to prevent reverse flow. There is an auxiliary connection provided with plant air for testing or emergency pressurization if demineralized water is unavailable. The design pressure is 150 psig up to the connection to the tubesheet. The IGTS cavity design pressure is 45 psig. Each unit has an independent TSP subsystem.
SD-29 l
Rev. 2 Page 15 of 85l
Redundant filters ensure that adequate water quality is maintained at the IGTS cavity to prevent clogging. Redundant pressure-reducing valves regulate the pressure to 35 psig, which will maintain a 10 to 25 psi differential above the water box pressure. A PRV bleed-off control valve is provided to maintain desired downstream pressure-reducing valve pressure during periods of no or low flow. The bleed-off discharge is direct to the Equipment Drain System.
Two flow switches monitor the flow to the inlet and outlet tubesheets and provide an alarm at the local control panels when the maximum permissible flow rate of 1 GPM is exceeded. Demineralized water supply low pressure or filter high D/P will also alarm at the local panels. A common annunciator will alarm in the Control Room for any of these conditions.
Each tubesheet supply line contains individual flowmeters which can be valved into service to identify the leaking tubesheet. The flow meters are normally bypassed during operation.
Each supply line is connected to the corresponding tube-sheet in four places and is fitted with a pressure-relief valve. Each tubesheet is fitted with four capped vent lines.
The system, as described, is mounted on a support rack located directly west of the condensate pump pit in Units 1 and 2 at elevation 20'. The rack provides connection points for the Demineralized Water System, the eight supply lines to the tube sheets, and electrical and alarm wiring to adjacent electrical panels. In addition, the necessary isolation valve, check valves, gauges, electrical control cabinet, and nameplates are mounted on the support rack.
2.2.1 Instrumentation The arrangement and installation of all equipment are shown on Drawing F-7358.
- 1.
The pressure indicating gauges are Bourdon tube type.
- 2.
The pressure differential switches (PDS) measure the pressure drop across the filters. The PDS is a diaphragm type with watertight housing, an adjustable differential range of 3.0 to 40 psig, and a maximum working pressure of 150 psig. At normal operation (approximately zero flow), there will be no differential pressure. The PDS alarm contact will be set to open when the differential exceeds 15 psid to activate the alarm.
SD-29 Rev. 2 Page 16 of 85
- 3.
The pressure switch is located after the pressure-reducing valves to detect inadequate pressure supplied to the tube sheets. The switch is a diaphragm type with water-tight housing and dual settings. The switch has an adjustable range of 0.5 to 80 psi and maximum test pressure of 160 psig. At normal operation, the pressure will be approximately 35 psig. The switch will be set so that the alarm contact will open when the pressure drops below 20 psig to activate the alarm.
- 4.
Eight flow gauges, one on each branch to a tube sheet, detect the leakage rate for that tube sheet. The gauges are glass tube rotameters with a flow range of 0 to 1.4 gpm water, and 2% accuracy.
- 5.
Two flow meters with alarm switch components, one on the inlet tube sheet branch and one on the outlet tube sheet branch, constantly monitor for flow to detect the total leakage rate for each set of four tube sheets and actuate an alarm when the maximum permissible leak rate is exceeded. The flow meter components are glass tube rotameters with an adjustable alarm contact with a flow range of 0 to 8.4 gpm water, and 2% accuracy. At normal operation, there will not be any leakage or flow. The switch will be set so that the alarm contact will open when the leak rate exceeds 1 gpm to activate the alarm.
2.2.2 Filters Redundant filters are provided to ensure a clean supply of demineralized water to the succeeding instrumentation and the tube sheets. The filters are canister shells with replaceable, 20 micron cotton filter cartridges with a flow range of 4-20 gpm, and maximum operating pressure of 150 psig.
2.2.3 Valves 1.
Redundant pressure-reducing valves (PRV) are used to reduce the incoming demineralized water pressure to approximately 35 psig.
The PRVs are diaphragm-operated type with a stainless steel diaphragm and an adjustable outlet pressure range of 0 to 50 psig. A bleed-off control valve (V-1 0) is provided to maintain desired downstream pressure-reducing valve pressure during no or low flow condition.
- 2.
Ball valves are used throughout the system for shut-off service.
SD-29 Rev. 2 Page 17 of 85
. 3.
- Two check valves are installed in the inlet line to ensure-against back flow to the Demineralized Water System. In addition, one check valve is located in each supply line to the tube sheets.
- 4.
Pressure-relief valves to prevent overpressurization of IGTS cavity will be preset at 50 psig (+/- 5 psig).
2.2.4 Support Rack The support rack is a welded, structural steel frame designed and constructed for mounting the components and control valves of the TSP System.
Rack dimensions are approximately 10' high by 9' wide.
2.2.5 Local Annunciator Panel The local annunciator panel is a 30" x 24" x 10" NEMA-12 electrical enclosure mounted on the wall near the support rack. This panel houses the alarm push buttons, alarm indicating lights, power indicting light, and the necessary electrical equipment. The panel displays one white indicating light to show when the electrical power is on and five red indicating lights with reset buttons to show which of the monitor switches are alarming and to provide reset capability. An alarm at the local panel will activate an annunciator on UA-24 in the Control Room.
2.3 Condenser Water Box Cathodic Protection Subsystem The Condenser Water Box Cathodic Protection provides corrosion protection to each condenser water box and tubesheet. Cathodic Protection impresses electrical direct current to the metallic structure in sufficient quantity to counteract effects of galvanic corrosion.
SD-29 Rev. 2 Page 18 of 85
A potential difference will usually exist between two dissimilar-metals when they are-immersed in a corrosive or conductive solution (electrolyte). If these metals are placed in contact (or otherwise electrically connected), this potential difference produces electron flow between them. Corrosion rate of the less corrosion-resistant metal is usually increased and attack of the more resistant material is decreased, as compared with the behavior of these metals when they are not in contact. The less resistant metal becomes anodic and the more resistant metal cathodic. Usually the cathode or cathodic metal corrodes very little or not at all in this type of coupling.
Because of the electric currents and dissimilar metals involved, this form of corrosion is called galvanic, or two-metal corrosion. The driving force for current and corrosion is the potential developed between the two metals.
In the case of the condenser water boxes the conditions for this type of corrosion exist.
The electrolyte is the circulating water itself while the dissimilar metals are the water box (carbon steel) and the tubesheets (aluminum bronze).
Several methods are available to reduce galvanic corrosion. The one used in the circulating water system is cathodic protection. A third dissimilar metal (niobium rod coated with platinum) is placed in the circulating water in the condenser water boxes. A positive potential is applied to this anode, forcing a current through the circulating water to the water box and to the tubesheets. Now both of the metals we would like to protect are cathodic and corrode very little.
The anode used is referred to as an impressed-current anode. It has the ability of releasing electrons to the electrolyte while undergoing very little corrosion (loss of material).
The chemical reactions which form on the surfaces of the water boxes and tubesheets (cathodic metals) provide a barrier between these surfaces and their environment. This can actually be considered a coating; i.e., a coating that can be continually replenished. This barrier can be measured with the use of a voltmeter and a reference electrode placed close to the coated surface.
This measurement is called a structure-to-electrolyte potential. A voltage shift or change in potential from the native static potential is required for cathodic protection to be complete.
To establish the potential required between the anode and the water box and tubesheet a direct current (DC) source is required. In the condenser water box cathodic protection system AC to DC rectifier units are used.
SD-29 Rev. 2 Page 19of 85
A total of eight cathodic protection subsystems are provided for each Unit's condenser at BNP. Each subsystem includes one rectifier, five anodes, four reference electrodes, one terminal box, and one junction box. These subsystems are provided to supply cathodic protection current to the eight condenser water boxes (four inlet and four outlet) which are part of the condenser system for each unit.
The eight cathodic protection subsystems are divided into two groups, one for the A shells and the other for the B shells. The four rectifiers for each group are housed in a single cabinet located in the breezeway beyond the condenser bay shield wall.
2.3.1 Rectifier The rectifier has a 3 phase Delta/Wye transformer suitable for 480 Vac input. Direct current output is rated at 30 volts, 40 amps. The unit is air-cooled with silicon controlled stack elements. Transformer control is stepless with a continuous adjustment from zero to rated output using a small potentiometer. Output can be adjusted manually with the potentiometer or automatically with the use of the potential controlled automatic circuit (APC circuit). The unit will normally be operated on automatic control with the use of a reference electrode lead and a structure (ground) lead tied into the potential controlling circuit.
The rectifier unit is electronically protected against damage due to external short circuits. By this, it is meant that the unit will operate indefinitely under short circuit conditions without exceeding its set output rating.
Additionally, the unit has a filtered output for increased conversion efficiency and reduced electrical interference and AC input DC output lightning arrestors.
A dual light alarm is provided to indicate normal operation (red light on, amber light off),
shutdown or loss of AC input power (no lights), and lack of adequate output dc/impressed potential (amber light on, red light off). This light alarm system is tied into the annunciator alarm system in the Control Room. The Control Room annunciator will sound on loss of AC input and/or lack of adequate output dc/impressed potential. An alarm cutoff switch is provided inside the rectifier unit so that the Control Room annunciator may be bypassed.
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2.3.2 Anodes Each water box enclosure is provided with five anodes(a total of 40 anodes for both condenser shells). The anodes penetrate through the water box enclosure with the aid of the opening provided and a flange assembly. The anode element is a /2" diameter x 9" long niobium rod with a 200 microinch coating of platinum. A 9" long fiberglass standoff shield is provided up to the mounting assembly. The mounting assembly has a 1/2" NPT strain relief cable gland to provide access for the anode cable connection. There is a brass screw fitting inside the anode head for this connection. The cable connection extends from the anode, through conduit, to a terminal box located on the water box.
2.3.3 Terminal Boxes A terminal box is provided on each water box enclosure (a total of eight terminal boxes for both condenser shells). These terminal boxes are provided to easily disconnect the anode, electrodes, and structure connections when the water box is removed. The terminal box is a NEMA Type 4 enclosure. A terminal block is provided within to accommodate five anode leads, four reference electrode leads, and one structure lead. This structure lead is provided for the automatic controller at the rectifier.
2.3.4 Junction Boxes A junction box is provided for each cathodic protection system (a total of eight junction boxes for both condenser shells). Each junction box (in groups of four) is located on a panel board which is adjacent to their respective rectifier cabinet. This junction box serves as a termination point for the five anode leads and four reference electrode leads from each water box. The automatic circuit structure lead is also routed through this box. The five anode leads are fused and shunted through this box and terminated on to a common bus bar. A new positive anode lead is routed from this bus bar to the positive (anode) DC lead at the rectifier.
The four reference electrodes are terminated to a selector switch. The selector switch terminal and structure terminal is metered using a 0 to 1.5 voltmeter and again terminated on the opposite side of the circuit. The selected reference electrode lead and structure lead is then routed from the junction box to the rectifier control circuit (control card located within the rectifier).
SD-29 Rev. 2 Page 21 of 85
2.3.5 Negative Connections A 1 0/AWG DC cable is routed from each condenser (cable is cadwelded to the condenser shell except for the 2A North inlet which is lugged and bolted in place) to the common negative terminal of the rectifier cabinet. Four negative cables are then provided from this terminal to the negative output terminals of each rectifier. This cable is not routed through the junction box. This connection completes the DC circuit.
2.3.6 Reference Electrodes Each water box enclosure is provided with four reference electrodes (a total of 32 electrodes for both condenser shells). The electrodes penetrate through the water box enclosure with the aid of the opening provided and a flange assembly. The electrode element is a 3/8" diameter x 1" long zinc rod. A 10" long fiberglass standoff shield is provided up to the mounting assembly. The mounting assembly has a 1/2" NPT strain relief cable gland to provide access for the electrode head for this connection. The cable connection extends from the electrode, through conduit, to a terminal box located on the water box.
2.3.7 Alternate Current Power There is a common 480 Vac (3-phase) input terminal within the rectifier cabinet. There is a fused disconnect switch at this terminal. Alternating current power connections to each rectifier are prewired from this point.
Each rectifier unit within the cabinet is provided with input circuit breakers.
2.3.8 Direct Current Meters Each rectifier front panel is provided with three DC meters. The top meter is a reference potential meter which is measuring the difference in potential between the selected zinc reference electrode and the water box structure. This meter also measures the selected or set potential between the above. This set potential is selected in the field when placing the cathodic protection system on line. A switch is provided on the auto-volt control card to select either the "set" or "ref" potential read. When the system is on auto-volt control the "ref potential" should be the same as the "set potential" if the system is operating and controlling properly.
SD-29 Rev. 2 Page 22 of 85
The center meter is the DC voltmeter. This is the total voltage attributed to the DC, circuit and includes the anode-to-electrolyte, electrolyte, electrolyte-to-cathode, and metallic circuit IR drops.
The bottom meter is the DC ammeter. This measures the total current flow through the DC circuit.
There is also a potential meter inside each junction box. This meter is essentially identical to the first meter described above. This meter is capable of measuring all four reference electrodes with the aid of a selector switch. This meter reads ref potential only. It does not read the set potential. The reference electrode to be used as the controlling electrode will be determined when placing the system on line.
2.4
)
NOTE:
T 1
Unit 2 ball collection strainers have been abandoned in place per ESR 97-00576.
IFOR
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aining a
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nIaeUliy II I lsUllIyUI I typ of P. The following list provides a d
specifies the proper use of each type.
- 1.
26 millimeter (soft texture, open-cell surface, blue in color), used for normal operation the majority of the year (April through November),
when Circ. Water flow is restricted to 1105 cfs.
- 2.
25 millimeter (soft texture, open-cell surface, orange in color), used for cold water operation during the months of December through March, when Circ. Water flow is restricted to 922 cfs.
I SD-29
.I Rev. 2 Page 23 of 85 1 '
I SD - 9ev 2Pa e 2 of 8
3.-
26 millimeter (hard texture, smooth surface, blue in color), used for high flow operation during the months of July through September, when Circ. Water flow restrictions allow four (4) pump operation.
- 4.
24 millimeter (abrasive band), used after extended shutdowns or extended periods when AMERTAP System is out of service. The CW System Engineer should be contacted prior to introduction of these abrasive balls to the system. This ball should only circulate for a few days and then be changed out for the type ball used normally for that time of year.
- 5.
The first two types of balls are interchangeable if the required type becomes unavailable.
Th rouglheapeuseglb.__
1P hl Hi Abs. Ea ws ser con
~'i~,6s bth of it's water btball srti1aI spms and a AME a
_ane&
and routed to t e collector unit by the recirculaboripwips.IThe.ba.co
- titffrer, located in-
- Tscreens, two ltrianrrs are abandoned in place on Unit 2).
The upper screens funnel the balls to the lower screens which, in turn, direct the balls to the ball recirculating pump suction piping. Due to a high flow rate through the strainer, a small quantity of balls are trapped against the lower screens.
As the balls pass to the lower screens, they are accelerated by the upper screen hydrofoil section. The acceleration of the balls aids to minimize the number of balls trapped. Operations of the throttle flap to reduce flow through the strainer also aids in minimizing the number of balls trapped.
During ball collection, the shut-off flap is utilized to backwash the lower screens which frees any trapped balls.
The collector unit consists of ball recirculating pump and a vertical collector cylinder.
The recirculating pump is a centrifugal pump with an impeller designed to compress the individual balls. Due to this compression, the air trapped within the balls is released. The recirculating pump receives the balls from the ball collecting strainer and provides the necessary driving head to direct the balls through the collector cylinder to the injection nozzles.
SD-29 Rev. 2 Page 24 of 85
The collector cylinder is equipped with a viewing window to verify flow and to provide a means of visually inspecting the balls during system operation. The cylinder is also equipped with a ball collecting flap. During ball collection, the flap is adjusted to block the collector cylinder ball discharge.
At the collector unit, the cycles can be interrupted at any time to count balls, check ball sizes, or take the balls out of service. Size reduction, due to the wear, will require ball replacement. This is also accomplished at the collector unit.
From the collector unit, the balls are routed to the injection nozzles via a ball distributor.
On Unit 1 only, the ball distributor is manually positioned to direct the balls to either or both of the condenser shell inlet water boxes. On Unit 2 ball distributor position vanes have been removed by ESRs 97-00219 and 97-00247. The balls travel on to the injection piping. Upon entering the condenser, the balls travel the length of the tubes utilizing the pressure differential between the tube inlets and outlets as the driving force. A minimum pressure differential of 4.2 ft. of water is required for proper system operation.
2.5 Condenser Water Box Air Removal Subsystem A Condenser Water Box Air Removal Subsystem establishes and maintains a prime at the high point of the circulating water system. This system consist of a priming tank and two vacuum pumps. This equipment is centrally located between Unit 1 and 2 main turbine generators at the 70' elevation of the turbine building. The system is tied into the air removal headers for the water boxes of both unit's condensers thus providing a common vacuum source and system to both BNP units.
When the circulating water system is first started up, the inlet water boxes are vented to atmosphere through a vent line which is part of the water box air removal system. If the system is to be operated with the mode selector switch in the C or D positions the water box removal system must be started. It is optional as to whether or not the system is operated when the mode selector switch is in the B position. The vent path for the inlet water boxes is secured and both the inlet and outlet water boxes are aligned to the air removal system.
The vacuum pumps are started by selecting pump 2A or 2B with the lead/lag selector switch. The pump that is selected as the lead pump is then started by placing its control switch in the AUTO position. Once the lead pump is running the control switch for the pump selected as the lag pump is placed in AUTO.
SD-29 Rev. 2 l
Page 25 of 85
When the Vacuum Priming Tank is less than 18" Hg, the Lead Air Removal Pump starts and runs until about 24" Hg vacuum is obtained. When the Priming Tank is less than 12" Hg the Lag Air Removal Pump will Auto start and run until 18" is obtained.
A water box level indication system with instruments is located in the turbine building outside of the condenser bay in the vicinity of the condensate pumps. Each gauge indicates in feet of water with a range of 0 - 40 ft. 40 ft equals elevation 62' - 4" or 23.83 ft above the water box in the air removal line.
Each inlet and outlet water box has a valved connection to the respective inlet or outlet air removal header. Each valve at a water box is equipped with a debris screen to assist in prevention of drawing AMERTAP balls into the Air Removal Subsystem.
2.6 Turbine Building Condenser Pits There are three Turbine Building Condenser Pits, two on the outlet end of the condenser (Northwest and Southwest) and one on the inlet end of the condenser (East). The outlet end pits are automatically pumped to the inlet end pit by electric driven sump pumps. There is a manually controlled inlet pit electric sump pump to the salt water release tank. Radwaste should be notified any time this pumping is initiated to ensure there is sufficient room in the salt water release tank. The amount to be transferred can be calculated by multiplying the inches to be pumped times the gallons per inch given in the Operating Procedure (1495 gaVinch). The air driven sump pumps have a capacity of approximately 50 gpm. The time to pump a sump can be calculated dividing the pump capacity into the volume to be pumped.
Each Turbine Building condenser pit has three level detectors. One initiates an annunciator in the Control Room if level should reach 10". The second initiates an Hi level light on the Flooding Status Panel at 60". The third initiates a Hi Hi level light on the Flooding Status Panel at 108". The 108"'
switch confirmed by the 60" switch will trip all of the operating CWIPs on the affected unit.
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2.7 System and Component Design Paramet 2.7.1 System Parameters Seasonal water temperature variations u
n it 2.7.2 Component Design Parameters
- 1.
Circulating Water Intake Pump Design head (TDH)
Shutoff head Minimum submergence Design speed Critical speed Efficiency at normal load Power consumption
- a. Design load
- b. Shutoff Maximum time pump can operate at low water level Bearing cooling water
- a. Quantity
- b. Pressure ers 400F to 900F 41.89 ft.
98 ft.
10ft.
360 rpm 1385 rpm 87%
1955 hp 3750 hp continuous 7gpm 20 psig SD-29 Rev. 2 Page 27 of 85
- 2.
Circulating Water Intake Pump Motor Make Type Rated horsepower Speed Voltage Phases Rated load Design head Shutoff head Minimum submergence Design speed Critical speed Efficiency at normal load Power Consumption
- a. Design load
- b. Maximum Minimum time pump can operate at extreme low water level Bearing cooling water
- a. Quantity
- b. Pressure Electric Machinery Induction 2500 hp 360 rpm 4000 Vac 3
349 amperes Pump 1 1.6 ft.
43ft.
9ft.
277 rpm 800 rpm 82%
612 hp 690 hp (at high tide) continuous 6 gpm 15 to 20 psig l SD-29 I
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Page 28 of 85 l
2.7.4 Circulating Water Discharge Pump Motor Make Electric Products Synchronous Type Rated horsepower 800 hp Speed 277 rpm Voltage 4000 Vac Phases 3
Rated load 91 amperes Seasonal water temperature variations 400F min to 800F N
o _3P
- u n Thit 3.0 INSTRUMENTATION AND CONTROLS 3.1 Circulating Water System Control Various startup control functions associated with the operation of the Circulating Water System are operator initiated. Automatic shutdown functions are provided for equipment protection. System interlocks are provided for pump protection and system integrity.
During normal operation, the system is remotely controlled from the RTGB, XU-2 Panel, in the main Control Room. The Caswell Beach Pumping Station has a local control system in addition to the remote.
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3.2 Component Control 3.2.1 Circulating Water Intake Pump Control Prior to CWIP startup for either unit, the valve train mode selector switch CW-CS-1 014 must be selected to the "D" position. The purpose of the mode selector switch is to throttle the condenser outlet valves to maintain, the water boxes full.
The valve train mode selector switch is a-four position (A-B-C-D) switch. Selection of the appropriate switch position automatically throttles the condenser discharge valves to the position necessary for the various intake pump combinations. The following pump combinations are associated with the individual mode selector switch positions (refer to OP-29 Fig. 29-1):
- 1.
Position A - Not normally used; prevents pump start.
- 2.
Position B - Used with waterbox air removal out-of-service; throttles condenser outlet valves open to winter flow rate setting.
- 3.
Position C - 3 pumps on 4 water boxes; throttles condenser outlet valve to open to normal flow rate setting.
- 4.
Position D - 4 pumps on 4 water boxes; throttles condenser outlet valves open to position allowed in the summer on one unit only.
The correct mode selector switch position to initiate a pump start is always position "D".
After the pump start, the mode selector switch is returned to the position associated with the number of operating pumps.
When the CWIP control switch is taken to the START position, the pump discharge valve begins to open. As the valve passes through the 12% open position, a limit switch initiates the pump motor start signal. The valve continues to the 100% open position. The discharge valves are equipped with two speed actuators which will stroke the valve from 12% to full open in 15 seconds.
I SD-29
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Placing the CWIP control switch in the STOP position initiates the closing of the discharge valve. The two-speed actuator will close the valve in 30 seconds. As the discharge valve passes through the 34% open position, the pump automatically trips. If the pump trips for any other reason the discharge valve will also return to the fully closed position.
The circulating water intake pump will trip if any of the following conditions occur:
- a.
Low lube water flow at 7.0 GPM
- b.
Discharge valve less than 34% open for any reason
- c.
Instantaneous overcurrent at 2400 amps (50/51 device)
- d.
Time overcurrent at 1200 amps for 29 seconds (50/51 device)
- e.
Unbalanced phase current at 3 amps difference for 3 seconds
- f.
Differential current or phase angle in all 3 phases
- g.
- h.
Turbine Building Flood Detection System Hi-Hi level at 108 inches with confirmatory Hi level at 60 inches.
- i.
Traveling screen differential Hi-Hi at 48 inches. If the water level differential across the CW screens exceeds 60 inches collapse of the screen and/or cavitation of the pumps could occur.
- j.
Motor winding Hi-Hi temperature (Annunciation only)
- k.
Motor bearing temperature Hi-Hi (Annunciation only)
Other than for emergencies the CWIP configuration should not be changed when Intake Canal Level is less than zero feet Main Sea Level (MSL) as read on the Intake/Discharge Canal Recorder, SCW-LR-285/CW-LR-761. This avoids tripping the pumps with fine mesh screens on high DP.
NOTE:
Available setpoints are listed in Table 29-5.
3.2.2 Condenser Isolation Valve Control Each condenser inlet and outlet isolation valve has automatic and manual modes of control selectable at the RTGB. During normal operation, isolation valves are controlled in automatic by the valve train mode selector switch. The manual mode of control is used to isolate a particular water box. In the manual mode, each condenser inlet-outlet isolation valve pair is controlled by its own control switch. These switches are CW-CS-418 through CW-CS-421.
SD-29 Rev. 2 Page 31 of85
3.2.3 Circulating Water Ocean Discharge Pump Control The CWOD Pumps can be operated either locally at Caswell Beach or remotely from the Control Room. A local/remote control switch at Caswell Beach determines the controlling location. When the local/remote control switch is in the LOCAL position the start/stop control switch at Caswell Beach can be used to control the pump. When the switch is in REMOTE the start/stop switch on the RTGB is used to control the pump via the supervisory control system. When shifting between remote and local operation caution must be taken to ensure both control switches are in the same position; i.e., if the pump is being controlled remotely and is running, the pump would stop if the local control switch is in the STOP position and control is shifted to local.
The START command will initiate opening the pump's discharge valve. The pump will start when the valve reaches 50% open. After the pump start, the valve continues to fully open.
Taking the CWOD control switch to the STOP position initiates the closing of the discharge valve, tripping the pump as the valve passes through the 50% open position. The CWOD will trip if any of the following conditions occur:
- 1. Motor and pump bearing lube water flow low at 6.5 GPM
- 2. Discharge valve less than 50% open for any reason
- 3. Instantaneous overcurrent
- 4. Time overcurrent NOTE:
Available setpoints are listed in Table 29-5.
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3.2.4 Circulating Water Discharge Pump Lube Water Pump Control The CWOD lube water pumps can be operated either locally at Caswell Beach or remotely from the Control Room. A local/remote control switch at Caswell Beach determines the controlling location. When the local/remote control switch is in the LOCAL position the auto (on)/stop control switch at Caswell Beach can be used to control the pump. When the switch is in REMOTE the auto (on)/stop switch on the RTGB is used to control the pump via the supervisory control system. When shifting between remote and local operation caution must be taken to ensure both control switches are in the same position; i.e., if the pump is being controlled remotely and is running, the pump would stop if the local control switch is in the STOP position and control is shifted to local. The pumps are designed to operate alternately with an interlock preventing the operation of both pumps simultaneously. During manual control, whether from the Control Room or from the local control panel, a selected lube water pump responds to a manually initiated ON command only if the lube water discharge header pressure is less than 30 psig. In automatic control, the pump automatically starts if header pressure is less than 30 psig.
Once a pump is started it will run continuously unless it is manually stopped.
During circulating water discharge pump operation, a lube water pump is continuously run to prevent the accumulation of sand and other abrasives on the bearings and seals of the discharge pumps.
3.2.5 Supervisory System The supervisory system consists of a master station located in the Control Room and a remote station located at the Caswell Beach Pumping Station.
Control of the system is from the RTGB. The signals are transmitted via a microwave system. The supervisory cabinet in the Control Room (XU37) provides controls and indications of the status of the microwave system.
SD-29 I
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Each supervisory control point (control switch for operating a component) is provided with a point select push button. Point select push buttons are the lighted type which illuminate only after the master station confirms a valid message from the remote station. The point select push button permits an operator to perform a specific control function. When the point select button of a selected point to be controlled is depressed, the master station will transmit a signal to the remote station where it is checked for validity. A valid message will illuminate the checkback lamp on the selected point push button and allow the operator to perform the control function. Selection of a control point blocks selection of all other control points.
After selection of a control point, the operator has ten seconds to perform the control operation. After ten seconds, the supervisory system automatically resets. As the controlled device changes position, position indicating lamps will show the new status. Should a device change position without the operator initiating the change, the new status indicating light will flash and an alarm will be annunciated.
System Operating Enhancements:
By replacing Quindar with an Allen Bradley SLC 500 controller several intuitive enhancements were easily programmed into the system. These were added to assist the operator in operation of the U1 & U2 Caswell Beach supervisory system. The new system will do the following:
1.
Detect loss of valve/breaker position or parameter indication inputs.
If.RTGB valve or breaker indication is not present for a certain period of time, then the output indication for the missing inputs flash fast. A bypass feature is included on the 4 MWOD valves and 2-480V breakers (incoming and tie). This will allow for these pieces of equipment to be taken out of service for a period of time without leaving the loss of parameter indication computer point in on the process computer and the Caswell Beach supervisory trouble annunciator in (along with device's indication flashing lights) on the RTGB. This feature (See 1&2APP-UA-05-2-1) is enabled by turning the position switch of the CWOD pump or 480V breaker to the trip position and holding point cancel down at the same time. The bypass will be disabled and automatically reset when open indication of the MWOD valve or 480V breaker is received.
SD-29 Rev. 2 Page 34 of 85
- 2.
Prevents masking of common annunciators through a re-flash feature. If a Caswell Beach breaker trip annunciation (UA24 1-7) has come in (the breakers open indication lights will also flash on the RTGB), and another Caswell Beach breaker trip comes in (its breaker open indication lights will also be fast flashing) before the first one clears, the Caswell Beach breaker trip annunciator will briefly go out and then come back in and flash at its alarm rate until acknowledged by an operator. All involved RTGB component indication lights will fast flash until supervisory reset is pushed, and then go solid. So now two breakers open indication lights are solid. This holds true also for UA24 2-7 (motor overload), UA24 3-7 (motor ground current),
UA24 4-7 (motor temperature high), UA24 5-7 (lube wa ter flow low),
and UA5 2-1 (CW Beach supervisory system trouble - re-flash not available with master station failure, because this causes loss of all logic determination). When the alarm condition clears, the corresponding indication will flash slowly, alerting the operator to hit supervisory reset.
- 3.
Performs actual breaker trip determinations based on presently monitored breaker parameters. The system is able to differentiate between a commanded open breaker and an actual breaker trip.
Therefore, a breaker trip annunciation is no longer received when a breaker is opened.
- 4.
It has enabled additional test features. It will test all annunciators and computer points, in addition to the normal white/red/green lamp test.
These will be particularly helpful in troubleshooting.
- 5.
It has enhanced operator status light indication.
- a.
The affected components status light will fast flash to indicate a trip or alarm.
- b.
The affected components status light will slow flash to indicate a reset of a trip or alarm.
- c.
The operator is prompted to cancel a command after a failed command execution.
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Page 35 of 85l
- 6.
The Supervisory system trouble computer points have been revised to work with this new Allen Bradley system
- a.
Loss of Communications (C1336) - Indicates modem malfunction or loss microwave link.
- b.
Remote Station Fail (C1339) - Indicates that the remote processor has halted due to a major error or is not in run.
- c.
Master Station Fail (C1338) - Indicates that the master processor has halted due to a major error or is not in run.
- d.
Loss of 24 VDC power supply/or loss of parameter indication (C1337) - It indicates that the Master stations 24 VDC power supply (Technipower) has malfunctioned (This provides power for the status lights on the RTGB) or loss of one or more parameter indication signals.
- 7.
The supervisory ready light never goes out, except on the loss of 24 VDC in the supervisory panel (1 (2)-JM7). It fast flashes when the above first 3 failures occur. These failures are not reset-able, until alarm condition has gone away. This light is normally on steady when the system is OK.
No changes to the control display location and or function have been made.
However, the corresponding RTGB switch indication lights for components in an alarm condition will fast flash until acknowledged with a supervisory reset, then go solid when acknowledged, and slow flash when alarm condition clears.
3.2.6 Debris Filter Backwashing (Figure 29-2)
Debris filter backwashing is performed on a daily basis to minimize marine growth within the filter or if a high differential pressure occurs across the filter. An annunciator actuates upon high differential pressure (80 inches water increasing) in the Control Room Annunciator Panel UA-01. A white light above the impacted condenser inlet valve also illuminates.
SD-29 I
Rev. 2 Page736 of 85l
To insure sufficient flow for backwashing filters, the valve train mode selector switch must be positioned in accordance with Figure 1 of OP-29. Flows in excess of the flow minimization guidelines are limited to eight hours per week or when system reserve is 200 mwe or less. (Flow minimization restrictions are shown in Table 29-1.) Adequate flow for backwashing is obtained by the isolation of debris filters or the starting of additional circulating water pumps. The minimum number of operating pumps required for an efficient backwash is 3 per OP-29.
Each filter requires a minimum of 114,000 gpm for backwashing.
The water box select switch and debris filter backwash select switch are operated in conjunction to initiate debris filter backwashing.
- 1.
Select the NORTH or SOUTH position on the water box select switch to select the correct condenser.
- 2.
Initiate backwashing by selecting a water box (A-BW or B-BW) on the debris filter backwash select switch
- 3.
Filter flush dump valve opens
- 4.
The following filter inlet butterfly valve operation is observed when backwashing a water box debris filter to direct the flow around the screen to wash it off:
- a. Valve drives 150% open and remains in this position for 5 minutes
- b.
Valve drives 50% open and remains in this position for 5 minutes
- c. Valve returns to the 100% open position 3.2.7 Temperature Indications Temperature elements throughout the circulating water system can be used to determine the amount of heat being added to the circulating water and thus the environment. These temperature elements can be read on the BOP computer. Two of the more important readings are the temperature rise across a condenser (BOP Type Log 4) and the average intake canal temperature.
SD-29 Rev. 2 Page 37 of 85
3.2.8 Flow Minimization Schedule The Circulating Water System is operated in accordance with a National Pollutant Discharge Elimination System (NPDES) permit to minimize larval marine growth intake and to maintain ocean discharge temperature within prescribed limits. Table 29-1 is a flow minimization schedule which provides the necessary guidelines for Circulating Water System operation. Normal full power operation is with three intake and three discharge pumps running per unit. Normal system configuration is for three of the four CW traveling screens on each unit to be equipped with fine mesh'(1 mm) screen panels.
The NPDES permit also requires intake and discharge temperatures to be monitored to avoid damage to the ecosystem.
The NPDES permit also states that CW traveling screens with fine mesh panels must be in operation as long as the associated CWIP is in operation. If use of any fine mesh screen is not possible, notice shall be provided to E&RC explaining why.
3.3 Tube Sheet Pressurization Subsystem Control 3.3.1 Control The system provides manual control by quarter-turn ball valves located on the support rack. Either filter or pressure-reducing valve can be valved out of service for maintenance while the other maintains operation. Bypass lines can be opened and the flow switches can be valved out for maintenance. To determine the location of major leaks, the bypass valve in the branch to each tube sheet can be closed forcing full flow through the flow meters.
3.3.2 Instrumentation
- 1.
Instrumentation which monitors the system parameters which provide an alarm on the local panel and which provide input to Control Room annunciation are listed on Table 29-5.
- 2.
Instrumentation which provide local indication at the support rack is listed on Table 29-3.1.
SD-29 Rev. 2 I
Page 38 of 85
3.4 Cathodic Protection Subsystem 3.4.1 Control The system provides manual control, by manually adjusting the potentiometer to the:
desired DC output, or automatic control with the use of the potential controlled automatic circuit (APC circuit). The system is put into.
service by manually closing the two 480 Vac disconnect switches (1/Inlet Waterboxes, 1/Outlet Waterboxes) located on the rack by the rectifier cabinets. The system normally operates in automatic control.
3.4.2 Instrumentation
- 1.
Instrumentation at Rectifiers Instrumentation, which provides local indication at the rectifiers, is listed below:
Instrument Description Range Top Voltmeter-DC Middle Voltmeter-DC Lower Ampmeter Reference Potential Total Voltage Total Current 0-1.5 Vdc 0-30 Vdc 0-50 Amps
- 2.
Instrumentation at Junction Box Instrumentation, which provides local indication at each junction box (8), is listed below:
Instrument Description Bange Voltmeter-DC Reference Potential 0-1.5 Vdc 3.4.3 Dual Light Alarm Each rectifier cabinet has a dual light alarm located on the rectifier cabinet. When the red light is on and the amber light is off, normal operation is indicated.
When the red light is off and the amber light is on, lack of adequate DC output is indicated. When both the red and amber lights are off, system shutdown/loss of AC input is indicated and an annunciator on UA-24 in the Control Room will alarm.
SD-29 Rev. 2 Page 39 of 85
3.5 AMERTAP Condenser Tube Cleaning Subsystem Control 3.5.1 Manual Control The condenser tube cleaning system is controlled from the local control panel located near the ball collector unit. The system had the capability to be operated automatically, but is now only operated manually. To operate the system, the Cycle/Test Switch is placed in the TEST position and the Startup section of the Operating Procedure is followed.
When operating the system manually caution must be taken to ensure the upper and lower screens are operated correctly. Screens must be closed when system is in operation to collect balls (on Unit 2, the ball strainers have been abandoned per ESR 97-00576 ). Improper operation of the screens can allow the AMERTAP Balls to be released to the discharge canal. Wildlife, especially sea gulls, might attempt to eat the balls.
3.5.2 Automatic Control Not Used 3.6 Condenser Water Box Air Removal Subsystem Control 3.6.1 Control Vacuum pump operation is initiated by off/auto/on switches and lead/lag pump select switches on the cover of the local control panel. There is a lead and lag vacuum pump. With pumps in the auto position, start will be by increasing system pressure (decreasing vacuum). Vacuum switches mount on the vacuum priming tank and each shall have a variable setpoint to start the lead pump with lead switch and start the lag pump with the lag switch. These settings are adjusted to suit the circulating water system hydraulic gradient. The vacuum pumps must have seal water flow. The pump start circuit will open a seal water supply solenoid valve. Water flow will be sensed and allow the seal water flow switch to make thus enabling a pump start.
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The vacuum pumps take suction from the vacuum priming tank which is connected to the tops of the inlet/outlet condenser water boxes on both BNP units.
The vacuum system may be manually isolated and vented on one unit while remaining in operation on the other.
Indication of vacuum system failure is made whenever pumps are selected to the ON or AUTO position and vacuum falls close to atmospheric pressure. An alarm will be indicated on annunciator UA-03 on both unit panelboards.
Water box air removal shall be isolated from a unit prior to shutting down the circulating water system. The air removal system does not provide advantage to the unit when the unit is off line, and shutdown of the system is recommended during periods of cold shutdown.
The water box air removal subsystem is located on the 70' elevation of the turbine building, east side, between the two unit main generators. The water box air removal vacuum pumps will be started from the local panel in this area. System valves other than the individual water box isolation valves are located in the same area.
Operator action will be required to startup and shutdown the system. Operation of the system is monitored by indication of system failure at the Control Room HVAC Annunciator Panel UA-03 on each unit.
3.6.2 Instrumentation There is a single control panel for local operation of the two vacuum pumps. The control panel enclosure is a stainless steel, NEMA 3 box as per specification 48-1 and is next to the vacuum pumps. The pumps receive power from MCC's 2TH and 2TL.The panel has an OFF-AUTO-ON selector switch for each pump, and a lead 2A (left) lead 2B (right) selector switch for lead pump selection. Vacuum switches provide control on priming tank vacuum. Initial setting shall be 12" HG absolute to start the lead pump, and 18" HG absolute to start the lag pump. Each switch shall be set for 6" HG differential.
Separate seal water control is required for each pump. -A solenoid valve to start seal water flow is wired in parallel with the motor starter coil. A flow switch is wired in series with the motor starter and shall close circuit to permit and maintain motor operation. A red run lamp and run time meter is wired in parallel with each of the motor starter coils and mounted on the panel cover to indicate the running pumps and a totalized time of operation.
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A third vacuum switch with DPDT contacts operates upon high absolute pressure, > 25" HG absolute, in the vacuum priming tank, indicative of vacuum system failure (N.C. and open on alarm). The DPDT contacts will provide annunciation at Unit 1 and Unit 2 Control Room panels.
Control panel logic will be such that annunciation shall not be made when both pumps are selected to OFF position.
There is a differential pressure gauge for each inlet water box. The gages use a connection on each water box at elevation 22'-4" as a variable leg.
All of the gages on a unit connect to a common point in the air removal header as a reference leg. Each gage indicates over a range of 0-40 feet of water. 40 feet provides indication of water being at 62'-4" elevation which is at the reference leg connection. Zero feet provides indication of water being at 22'-4" elevation which is the variable leg connection.
3.7 Power Supplies Table 29-2 provides a reference listing of power supplies for major circulating water system and associated support subsystem components.
3.8 Monitoring Instrumentation 3.8.1 Instrumentation Table 29-3.1 provides a reference listing of instrumentation for major Circulating Water System and associated support subsystem components.
Table 29-3.2 provides a reference listing of points associated with the system that is monitored by the supervisory system.
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3.8.2 Annunciators Table 29-4 provides a reference listing of annunciators for circulating Water System and associated support subsystem process variables. Consult the Annunciator Panel Procedures for the associated window numbers and appropriate response.
3.8.3 Process Computer Interface System operating parameter values can be obtained in text or graphical form from the plant process computer. Operating trends may also be established for both the short term and long term. A listing of special process computer points may be obtained using the Cross Reference List for*
analog inputs to the Plant Process Computer from OSD-55.
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3.9 Instrument and Control Setpoints Table 29-5 is a table of instrumentation that provides trip functions. In cases where an instrument from a system other than the Circulating Water System is listed, the official setpoint and trip functions will be found in the system description to which that instrument belongs.
NOTE:
Setpoints for devices not listed in the Instrument and Control Setpoint table may be specified in other design or procurement documents. The following documents should be researched in the specified order to identify these setpoints:
- 1.
EDBS (Screen 455)
- 2.
Instrument schedules (LL-7000 and LL-70000 series drawings)
- 3.
P&ID for the system
- 4.
Associated drawings (reference EDBS for associated drawing numbers)
- 5.
Instrument Data Sheets (for GE-supplied equipment)
- 6.
Procurement specifications and related data sheets
- 7.
Purchase order documentation
- 8.
Vendor manual If, after the above investigative steps have been pursued, the setpoints are not identified, then the appropriate System Engineer should be contacted for guidance.
This note was inserted to comply with Quality Check Concern Number 12279.
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4.0 SYSTEM OPERATION 4.1 Normal Operational Relationships 4.1.1 The Circulating Water system is placed in service in accordance with OP-29.
4.1.2 A procedural caution states that starting a CWIP can cause a voltage drop of sufficient magnitude that on occasion a momentary increase in Reactor Recirculation Pump speed will be seen. This is due to the scoop tube positioner operating characteristics.
4.1.3 I
a na#-0 ft.
T ice S ingiowtides 4.1.4 When isolating and draining a condenser circulating water box the open condenser discharge valve breaker(s) are placed in the off position. This step ensures that the water box is allowed to drain.
The drained water box Debris Filter Flush Valve breaker is placed in the OFF position after the valve(s) is OPEN to allow drainage on the inlet side.
4.1.5 The screen wash pumps associated with circulating water traveling screens also provide screen wash for the service water traveling screen. A screen wash pump must be in service when either the circulating water or service water traveling screens are in service to prevent debris or marine life carryover to the systems.
4.1.6 The screen wash system should be operated for one complete cycle (45 minutes) after a circulating water pump is secured to ensure that the screen is clean.
4.1.7 When backwashing the CWOD lube water strainers or motor cooling coils caution must be taken to ensure lube water pressure is not decreased to a point where the CWODs will trip. This is particularly true when operating the strainer backwash valve. The valve must not be opened greater than 50%. Modifications to improve this restriction are in progress.
4.1.8 Each ocean discharge pipe must have at least one pump running at all times to prevent silting of the piping.
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4.2 Abnormal Operation 4.2.1 AOP-33.0, "Oil Spills In Cape Fear River", discusses oil fouling of the condenser heat transfer surfaces and blockage of the fine mesh screens, and recommends the following:
- 1.
Reduce load and minimize circulating water flow
- 2.
Cycle circ pumps to avoid loss of vacuum due to oil fouling 4.2.2 4.2.3 AOP-37.0 "Low Condenser Vacuum", discusses actions related to the Circulating Water system. The removal of a circulating water pump (water box) above 60% power could cause a turbine trip and a reactor scram due to low vacuum.
AOP-37.1, "Intake Structure Blockages," discusses the following:
A high differential pressure across the circulating water intake traveling screens can result from a variety of malfunctions or outside influences including:
An increase in marine life entrained by the traveling screens.
An increase of debris in the intake canal from recent storms or excessively high or low tides.
Mechanical or electrical failure of the traveling system.
Ttaiilf he en Hi eva tting the passafel
_anaus routed a disthc f
H~and. From this point the at the intake remq umi rte c9o ndintion nd maximum tide conditions.
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Traveling scr t e^.y4wjjty e.tn and p
sE_ on change and the-amount of debris in the vicinity of the p an
-iudtfate. T&
Gr It'a__yga s
a som~f lry and is tr u
medium size buh s
s
- Aells, docks-W :.f the
- migg, they typically attach to hard structures and lited wave action during and afterstoranes may na se the rate that~rta 1aria fraqments are movl b~nto the i n trani rately effective only on the~i~tsi oe-erfis reans.
Detritius is the decay product of plant and animal mater. It has a characteristic brown muddy appearance and is very fine in texture. Detritius presents a significant hazard to the fine mesh screens, but will typically pass through the coarse mesh screens with minimal increase in screen dp.
Detritius is a particular nuisance in the summer-months during periods of lower tides. The primary reasons for this are the increase in the canal bottom temperature and the higher water velocity due to larger tidal amplitudes and increased number of CWIPs and SW pumps in the operation. The increase in temperature causes the organic debris in the bottom of the intake canal to decay at a higher rate. This biological decay process produces a hydrogen sulfide gas which builds up in the sediments and tends to loosen the detritius, making it more available for resuspension into the water column.
These resuspended particles can then be transported by the flowing water to the intake screens. Fire hose use on detritius is typically not effective because of the large quantities present. Increased pressure on the trash wash header is most effective on detritius.
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Marine vents are as unpredictable as
'dertsvens a
d~~'
~~i~~y~p ogo4At-he traveling scrll an gisms~ha~.
chanes i watr uai severe storm events nclha~f~~li~
aY e~rte re sig can dump large amo e ba s which force itiwed I normally loczte n,
downs reamoac I
scin marine life in the area to move down with the sa wembers.
Durin-g aiS a be cold rssesh ials ajtk sc j
u,.ember.
These cold asd spray header pressures me carryover is pre nt.
When a start signal is sent to a CWIP, it is important to remember that during the start cycle, water is being pushed back into the intake canal through the discharge valve for approximately 4 seconds before the pump receives a start signal. When a CWIP trips, it takes approximately 30 seconds for the discharge valve to travel full closed. During both of these events, significant mixing of the intake canal contents directly in front of the intake pump suction is occurring and can affect both units screens. Historical data indicates that this makes both units fine mesh screens especially vulnerable during a detritius incursion.
4.2.4 AOP-36.1 "Loss of any 4 kV Buses or 480 V E-Buses" has a step stating that; if required, to defeat the circulating water pump auto start, then place the CW Valve Train Mode Selector Switch in Position A. This will defeat the uncontrolled start of the CWIP due to the pump discharge valve being open when power is restored.
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4.2.5 Effect of CW System Losses Losses experienced in the Circulating Water system can have the following effects:
- 1.
Condenser Vacuum A loss in heat removal capability for the condenser will result in an increasing temperature condition. Since the condenser is a saturated system, this will result in a pressure increase or vacuum loss. Strong potential for turbine trip/reactor scram. Also a potential for loss of the preferred heat sink in accident conditions. A new AOP is being developed for intake structure blockages. See SD-29-1 for more information.
- 2.
Condensate System Loss of condenser cooling will result in a condensate system heatup as less heat can be rejected from the turbine exhaust steam. This will increase the potential for pump cavitation in the condensate system. It will also cause an increasing temperature condition in the components cooled by the condensate system.
- 3.
Main Turbine A loss of condenser cooling and subsequent increase in condenser absolute pressure results in a decrease of the delta-pressure across the turbine. This results in less turbine energy for electricity generation. The net result is a decrease in turbine efficiency.
- 4.
DC Electrical System A loss of DC panel 3(4)AB on site or CWA-3 at Caswell Beach will render the Caswell Beach Supervisory System inoperable.
- 5.
Releases A reduction in circulating water flow which provides dilution to the plant liquid radioactive release path will result in the concentrations of the releases to the environment being higher than acceptable. This could result in a loss of the release path or releases in excess of 1 0-CFR limitations.
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4.3 Interrelationships With Other Systems The Circulating Water System interfaces with the following systems:
4.3.1 Service Air provides testing and emergency supply to the TSP with a loss of demin water.
4.3.2 Conventional Service Water provides lubricating water to the CWIPs and system filling after maintenance. Caution must be taken when placing a TBCCW heat exchanger in service. If the valves are opened to fast the CWIPs lube water pressure might drop, tripping the pumps. Also when filling the circulating water system from service water, the valves must be slowly operated to prevent dropping service water pressure and causing the standby pump to start.
4.3.3 Provides dilution flow for liquid radioactive waste releases.
4.3.4 Ps (b
e a a orControl of dnIng nn, the When the chlorination system is aligned for injection to the circulating water system, the solution control valve will be closed when the associated pump is secured. When the pump is started the solution control valve will open when the CWIP discharge valve reaches 12% open.
When the CWIP is secured or trips the solution control valve will close when the CWIP discharge valve reaches 34% closed.
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5.0 RELATED INDUSTRY EVENTS 5.1 PS 3923, Manual Reactor Scram Due to Loss of Condenser Vacuum During Unit Startup Unit 1 was starting up following a refueling outage when operators manually scrammed the reactor due to decreasing condenser vacuum. All rods inserted as required. The turbine was not online during this event, and the lowest water level seen was approximately +140".
Prior to the manual scram, the unit was receiving main condenser Circulating Water intake pump (CWIP) screen high differential pressure trips. Upon pump restart, the pump would run for approximately 30 seconds prior to tripping again. Aquatic plant life (Gracilaria) impinged on the fine mesh CW traveling screens causing high differential pressure and resulting CWIP trips.
5.2 OE 2846, Circ Water Pump Trip Event Six (6) of seven (7) running condenser circulating water pumps tripped within a few minutes of each other causing a forced power reduction to 40% in one unit and a loss of circulating water on the shutdown unit.
The cause of the circulating water pump trips was high circulating water traveling screen differential pressure on fine mesh screens due to large number (clumps) of skeletal shrimp attaching to the screens. Brunswick's environmental permit requires three (3) out of four (4) traveling screens to be fine mesh on each unit. Skeletal shrimp have not been seen in such concentrations before. Low rainfall apparently resulted in decreased river flow and higher intake canal salinity.
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5.3 SER 7-96, Condenser Tube Failure On January 9, 1996, Crystal River Unit 3 was at 100 percent power when a condenser tube leak was detected. The unit was operating with Waterbox A isolated and open for maintenance. The source of the leak was quickly identified -as a main condenser titanium tube rupture in Waterbox B. (Waterbox B services the same low pressure turbine rotor as Waterbox A.). Because Waterbox A was out of service, Waterbox B circulating water pump could not be shut down while the turbine was in operation.
During this event, significant chemical contamination (including chloride) of the condenser hotwell, condensate and feedwater systems, and steam generators occurred. Plant procedures provided insufficient guidance for responding to rapid contamination ingress to the secondary system. As a result, operation continued while plant conditions were evaluated, and an operational decision to shut down and cool down the plant was unnecessarily delayed. In addition, the unit shutdown and cooldown process was further delayed because contingency plans for rapid cooldown of the plant with chemically contaminated secondary systems and components were not established.
Subsequent investigation determined that the saltwater in-leakage was caused by the circumferential failure of one condenser tube located near the center of the tube bundle below a drip pan. The tube severed midway between support plates.
5.4 SER 8-96, Icing of Traveling Screens and Trash Racks The Wolf Creek Generating Station experienced unusually cold weather conditions during the last week of January 1996. At approximately 2 a.m., on January 30, 1996, these weather conditions resulted in extensive icing of the circulating water intake structure traveling screens and frazil ice accumulation on the safety-related essential service water system intake trash racks. The frazil ice accumulation on the essential service water trash racks blocked lake water flow to one-of-two essential service water pumps.
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5.5 SOER 85-5, Internal Flooding of Power Plant Buildings Internal plant flooding occurs from breaches of water systems that are located inside plant buildings and are connected to large water sources such as lakes, rivers, or tanks. Such flooding has the potential to cause common mode failure of equipment necessary to maintain core cooling and can be a significant contributor to risk of core damage. Conditions that have led to internal flooding include the opening of Circulating Water systems for condenser cleaning or tube Repair; component failures such as pipe rupture, expansion joint failure, and valve or pump failures; and valve mispositioning.
5.6 CR 99-01661, Low Vacuum Trip Due to Fouling of Traveling Screens Unit 2 scrammed due to a low vacuum turbine trip from near rated power. The initiating event was multiple Circulating Water Intake Pumps (CWIP) tripping due to fine mesh screen fouling. Initial reports pointed to a fish run, but follow-up investigations revealed the fish were actually a minor contributor to the event. The most likely cause was detritus (Detritus is dead plant and animal matter. The very bottom of the food chain, detritus is the rotting leaves in the forest, the silt on the bottom of the pond, the thick dark mud in the salt marsh.) fouling caused by an astronomically low tide. The detritus fouling eventually caused a high differential pressure trip on the 2C CWIP. Based on the most recent soundings for intake canal depth, it is estimated that-the silt buildup is approximately four feet higher in front of the U2 circulating water intake structure vs. the Ul intake structure. The turbulence created when the 2C CWIP tripped caused the silt at the bottom of the canal to violently mix. This was due to the low tide and back flow through the CWIP discharge valve. The silt became entrained in the flow stream of the remaining operating CWIPs resulting in a cascade effects on the remaining operating fine mesh screens, and complicating recovery efforts.
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The inability to recover vacuum after the coarse mesh pump was started is most likely due to the hydraulics and thermodynamics associated with the positions of the CWIP discharge valves and their resultant effect on condenser vacuum at various locations in the condenser. This would have greatly affected CW flow to the condenser. The path of least resistance to flow would have been back through the intake canal rather than through the condenser. The rapid condenser vacuum response and the location of the instrumentation may have also played a role in this difference.
Similar Situations/Generic Implications An event involving a loss of condenser vacuum resulting in a manual reactor shutdown was reported in LER 1-95-011. This event involved impingement of gracilaria on the fine mesh screens installed on the operating CWIP traveling screens.
The gracilaria accumulation resulted from the combination of exaggerated high and low tides and stormy weather conditions that occurred prior to the event. The actions implemented to address this event focused on prevention of gracilaria and could not reasonably be expected to have prevented the event identified in this report.
Safety. Significance The safety significance of this event is minimal in that the affected systems responded as expected. In addition, ECCSs remained operable throughout the event. In addition, a total loss of condenser vacuum did not occur (i.e., vacuum decreased to 24.01 inches of mercury) and consequently, the normal decay heat removal path was maintained through the condenser during the event.
6.0 REFERENCES
6.1 Technical Specifications Applicable Technical Specifications should be referenced for requirements and bases.
6.2 Updated Final Safety Analysis Report W~teUtjdiesserv~ors Sectidfig>2 24 4.Structure St
$jA6System Sectio~h 4 13 i
W.
a-ehs'er Sat
~i lCodense Ct i na'ter~ystem Section 11.0 Radioactive Waste Management I SD-29 I
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6.3 Piping & Instrumentation Drawings Drawing Number Sheet No.
LL 22052 (Unit 1) 55A,55B,55C LL 2252 (Unit 2)
LL 70000 TSP Sys. (Unit 1) 1 LL 7000 TSP Sys. (Unit 2)
LL 70000 TSP Sys. (Unit 1) 2 LL 7000 TSP Sys. (Unit 2)
Iitla Valve Schedule Instrument Schedule Instrument Schedule Drawing Numher D-20034 (Unit 1)
D-2034 (Unit 2)
D-2051 Pump Bearing Lube Water D-17022 D-1 7023 D-17024 D-23011 (Unit 1)
D-2311 (Unit 2)
D-20042 (Unit 1)
D-2042 (Unit 2)
D-02348 Pressurization and Leak Detection D-20025 (Unit 1)
D-2025 (Unit 2)
Tifl-Circulating Water System Circulating Water Discharge and Turtle Blocker Panels Turtle Blocker Panels Turtle Blocker Panels AMERTAP Ball and Tube Cleaning Screen Wash Water System Integral Groove Tube Sheet Off-Gas Removal and Condenser Water Box Air Removal I SD-29 l
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6.3.1 Electrical Drawings Drawing Numbpr Titl D-23011 (Unit 1)
D-2311 (Unit 2)
D-20042 (Unit 1)
D-2042 (Unit 2)
D-02348 Pressurization and Leak Detection D-20025 (Unit 1)
D-2025 (Unit 2)
F-30027 (Unit 1)
D-9050 (Unit 2)
F-30028 (Unit 1)
D-03943 (Unit 2)
F-30029 (Unit 1)
D-03944 (Unit 2)
F-30030 (Unit 1)
D-3311 (Unit 2)
F-30031 AMERTAP Ball and Tube Cleaning Screen Wash Water System Integral Groove Tube Sheet Off-Gas Removal and Condenser Water Box Air Removal Electrical Wiring Schematic Alarm Panel Details Instrument Rack Electrical Physical Details Alarm Panel Internal Wiring Diagram Interconnection Wiring Diagram SD-29 Rev. 2 Page 56 of 85
Drawing Number Sheet No-Tlea F-37019 (Unit 1)
F-3719 (Unit 2)
LL 92013 (Unit 1)
"C5A" Condenser 1A(2A) Control LL 9213 (Unit 2)
LL 92013 (Unit 1)
"C5B" Condenser 1 B(2B) Control LL 9213 (Unit 2) 0-FP-9730 Units 1 and 2 Wiring Schematic Condenser Shell 1A and 2A 0-FP-9731 Units 1 and 2 Wiring Schematic Condenser Shell 1 B and 2B 0-FP-9732 Units 1 and 2 Water Box Penetration and Plan View Schematic 0-FP-9733 Units 1 and 2 Detail Junction and Terminal Boxes 0-FP-9734 Units 1 and 2 Bay Anode Penetrations Detail 0-FP-9748 Units 1 and 2 Rectifier Cabinet Detail 0-FP-9749 Units 1 and 2 Rectifier Cabinet Internal Detail MCC "1TC" Sht 3 IWD MCC "2TC" Sht 3 IWD MCC "1TC" ("2TC") Compt 79 80 Wiring and Cable Diagram MCC "1TC" ("2TC") Compt Wiring and Cable Diagram Cathodic Protection Cathodic Protection Cathodic Protection Cathodic Protection Cathodic Protection Cathodic Protection Cathodic Protection SD-29 Rev. 2 Page 57 of 85l
6.3.2 Specification Specification BX-M-029, Integrally-Grooved Tube Sheet Pressurization and leak Detection System, 6.3.3 Instrumentation Drawing Numbers Tit1e LL 70000 (Unit 1)
Circulating Water (CW) Instrument LL 7000 (Unit 2)Schedules 6.4 Control Wiring Diagrams Drawing N9tmrers I2 LL 92057 (9257)
Control Wiring Diagrams, MCC 1(2) SA LL 92013 (9213)
Control Wiring Diagrams, MCC 1(2) TC LL 92014 (9214)
Control Wiring Diagrams, MCC 1(2) TD LL 92015 (9215)
Control Wiring Diagrams, MCC 1(2) TE LL 92016 (9216)
Control Wiring Diagrams, MCC 1(2) TF LL 9218 Control Wiring Diagrams, MCC 2TH LL 9222 Control Wiring Diagrams, MCC 2TL LL 92025 (9225)
Control Wiring Diagrams, MCC 1 (2)TP LL 9268 Control Wiring Diagrams, MCC CWA LSD-29 I
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6.5 Modification Packages
- Plant Mod 81-227B Plant Mod 81-227C ESR-9700726 ESR-97-00051, Rev 0 ESR 97-00125, Rev 0 ESR 98-00096, Rev 5 ESR 99-00359 ESR 99-00185 6.6 Procedures 6.6.1 Procedures OP-29 OP-29.1 OP-29.3 OP-43 Fish Diversion Structure Screens and Frames Turtle Blocker Panels Recorder Modification, Unit 1 Recorder Modification, Unit 2 Caswell Beach Supervisory Equipment Supervisory Setpoints CW Waterbox Level Glasses Circulating Water System Screen Wash System Operation Procedure Amertap Condenser Tube Cleaning System Operation Procedure Service Water System SD-29 Rev. 2 Page 59 of 85
6.6.2 Technical Manuals Foreign Print Numher FP 20227 (Section 5)
FP 20227 (Section 3)
FP 3439 FP 9883 FP 9863 FP 9713 FP-901 5 FP-81 926 ihae CW Discharge Pumps, Ingersol-Rand CW Intake Pumps, Ingersol-Rand CW Discharge Pump Motor, Portec CW Intake Pump Motor, Electric Machinery Traveling Water Screens, FMC Corp.
Unit 1 CWIP Discharge Valve Actuator, Limitorque AMERTAP Ball Tube Cleaning System and Debris Filter Instruction For Debris Filter SD-29 I
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6.7 Miscellaneous 6.7.1 Equipment Specifications Specification Number Title 238-6 238-9 248-13 142-2 CW Intake Pumps CW Discharge Pumps CW System Butterfly Valves Caswell Beach Pumping Station Supervisory Control System Valve Actuators Self-Cleaning Debris Filter Waterbox Air Removal Vacuum System Foulant Release Coating of CW Piping 248-7 236-101 238-046 BNP-W-003 6.7.2 Specification Specification BX-M-022, Automatic Cathodic Protection System for Condenser Tube Sheets 7.0 TABLES Unless otherwise noted, the attached tables and drawings are for information only. For performing actions to meet the requirements of regulations, plant license, commitments or management directions, use the appropriate procedure and reference drawing or print.
SD-29 Rev. 2 Page 61 of 85 l
VI
=-~--.-
~-
uNalo y~
1cWstonts for-Month Four Water Boxes Three Water Boxes Flushing Debris Filters System Demand Max Disch No. of Sel SW No. of Sel SW No. of Set SW
- No. of Sel SW Rate Pumps in (Note 2)
Pumps in (Note 2)
Pumps in (Note 2)
Pumps in (Note 2)
Service Service Service Service r
3 B
3 B
3 B
4 D**
ov 3
C 3
B 3
C*.
4 D*
4 c3e 61 V4 C..
3 B
4 C**
4 D**
e C..
- Minimum flow for washing debris filters. Flows In excess of the flow minimization guidelines are limited to eight hours per week. Condenser water box air removal may be taken out of service when in the B position.
- C and D positions require water box air removal system in service, to maintain water boxes full.
- 'C position with 3 water boxes in service may require operation of condenser water box removal to maintain full water boxes.
NOTE:
NOTE 2:
Condenser water box air removal may be operated while in the B position, however, operation is normally not necessary to maintain full water boxes in the B position. C and D positions require condenser water box air removal system in service, because the water boxes can only be maintained full in these switch positions with condenser air removal system in service.
q-1,
/ qe 1-31 8Y II I;b C ASH/q~
- 5 4 Y 111.3° } 5 a;11173 4'fs@- 855 Yft3.5-SD-29 I l Rev. 2 Page 62 of 85
TABLE 29-2 Page 1 of 2 Power Supplies Component CWIP 1(2) A and C CWIP 1(2) B and D CWIP 1(2) A, B, C, D Discharge vIvs CWIP 1(2) A, B, C, D Diverting Zone Isol VIvs Cond 1(2) A-N and S CW Isolation vivs Cond 1(2) B-N and S CW Isolation vlvs Cond 1(2) A-N and S Debris Fit Flush vlvs Cond 1(2) B-N and S Debris Fit Flush vivs Cond 1(2) A-N and S Discharge vivs Cond 1(2) B-N and S Discharge vlvs Unit 1(2) Cathodic Protection Subsystem Unit 1(2) Condenser Tube Cleaning Subsystem Condenser Water Box Air Removal Vacuum Pump 2A Condenser Water Box Air Removal Vacuum Pump 2B CWOD Pump 1(2) A and B CWOD Pump 1(2) C and D Power Suppil 4160 bus 1(2) C 4160 BUS 1(2) D MCC 1(2) SA MCC 1(2) SA MCC 1(2) TC MCC 1(2) TE MCC 1(2) TC MCC 1(2) TE MCC 1(2) TF MCC 1(2) TD MCC 1(2) TC MCC 1(2) TP MCC 2TL MCC 2TH Cas Bch 4160V B Gas Bch 4160V A SD-29 I
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I.
TABLE 29-2 Page 2 of 2
.Power Supplies
-Component CWOD Pump 1(2) A and B Exciter Power Supply CWOD Pump 1(2) C and D Exciter Power Supply CWOD Pump 1(2) A and B Discharge vlvs CWOD Pump 1(2) C and D Discharge vlvs CWOD Lube Water Pump 1(2) A CWOD Lube Water Pump 1(2) B Power Suppl MCC CWA Bus B MCC CWA Bus A MCC CWA Bus B MCC CWA Bus A MCC CWA Bus B MCC CWA Bus A I SD-29 I
Rev. 2 Page 64 of 85
TABLE 29-3.1 Page 1 of 3 Monitoring Instrumentation FUNCTlON CWIP 1(2) A Disch Press CWIP 1(2) B Disch Press CWIP 1(2) C Disch Press CWIP 1(2) D Disch Press Cond Waterbox 1(2) A-N Inlet Level Cond Waterbox 1(2) A-S Inlet Level Cond Waterbox 1(2) B-N Inlet Level Cond Waterbox 1(2) B-S Inlet Level Cond 1 (2)A-N Debris Filter DP Cond 1 (2)A-S Debris Filter DP Cond 1 (2)B-N Debris Filter DP Cond 1 (2)B-S Debris Filter DP CWOD Pump 1(2) A Disch Pressure CWOD Pump 1(2) B Disch Pressure CWOD Pump 1(2) C Disch Pressure CWOD Pump 1(2) D Disch Pressure INSTRUMENT DESIGNATION 1 (2)-CW-PI-515 1 (2)-CW-PI-516 1 (2)-CW-PI-517 1(2)-CW-PI-518 1 (2)-CW-LI-5979-1 1(2)-CW-LI-5979-2 1(2)-CWW-LI-5979-3 1(2)-CW-LI-5979-4 1(2)-CW-DPT-7094A 1 (2)-CW-DPT-7094B 1 (2)-CW-DPT-7094C 1 (2)-CW-DPT-7094D 1 (2)-CW-PI-1 127 1(2)-CW-PI-1 128 1 (2)-CW-PI-1 129 1 (2)-CW-PI-1 130 INDICATOR/RECORDER
[OCATION Local Local Local Local Local Local Local Local 1 (2)-CW-PDI-519-1 XU-2 1 (2)-CW-PDI-520-1 XU-2 1 (2)-CW-PDI-521-1 XU-2 1 (2)-CW-PDI-522-1 XU-2 Local Local Local Local l SD-29 I
- Rev. 2 l I Page 65 of 85l
TABLE 29-3.1 Page 2 of 3 Monitoring Instrumentation INSTRUMENT DESIGNATION INDICATOR/RECORDER LOCATION FUNCTION 1 (2)-TSP-PI-1011 1 (2)-TSP-PI-1014 1 (2)-TSP-PI-1015 1(2)-TSP-PI-1019 1(2)-TSP-PI-1 020 1 (2)-TSP-FM-0001 1 (2)-TSP-FM-0002 1 (2)-TSP-FM-0003 1 (2)-TSP-FM-0004 1 (2)-TSP-FM-0005 Pressure gauge at inlet of filters Pressure gauge between filters and pressure-reducing valve Pressure gauge at outlet of pressure-reducing valve Pressure gauge at branch to inlet tube sheets Pressure gauge at branch to outlet tube sheets Flow meter at branch to inlet tube sheets Flow meter at branch to outlet tube sheets Flow meter to inlet tube sheet (Unit 1, B South; Unit 2, B South)
Flow meter to outlet tube sheet (Unit 1, B South; Unit 2, A North)
Flow meter to inlet tube sheet (Unit 1, B North; Unit 2, B North)
Local Local Local Local Local Local Local Local Local Local
-SD-29 Rev. 2 l
Page 66of 85
TABLE 29-3.1 Page 3 of 3 Monitoring Instrumentation INSTRUMENT DESIGNATION INDICATOR/RECORDER LOCATION FUNCTION 1 (2)-TSP-FM-0006 1 (2)-TSP-FM-0007 1 (2)-TSP-FM-0008 1 (2)-TSP-FM-0009 1 (2)-TSP-FM-0001 0 Flow meter to outlet tube sheet (Unit 1, B North; Unit 2, A South)
Flow meter to outlet tube sheet (Unit 1, A South; Unit 2, A South)
Flow meter to outlet tube sheet (Unit 1, A South; Unit 2, B North)
Flow meter to inlet tube sheet (Unit 1, A North; Unit 2, A North)
Flow meter to outlet tube sheet (Unit 1, A North; Unit 2, B South)
Local Local Local Local Local l SD-29 I
Rev. 2 Page67of85
POINT 3
4 5
6 10 11 12 13 14.
15 16 TABLE 29-3.2 Supervisory System Monitoring FUNCTION PARAMETER Indication CW Discharge Pump 1(2) A Breaker Position Indication CW Discharge Pump 1(2) B Breaker Position Indication CW Discharge Pump 1(2) C Breaker Position Indication CW Discharge Pump 1(2) D Breaker Position Indication Unit 1 (2) Bearing Lube Water Pump 1 Status Indication Unit 1 (2) Bearing Lube Water Pump 2 Status Indication Discharge Valve 1(2)-CW-V53 position Indication Discharge Valve 1(2)-CW-V54 position Indication Discharge Valve 1(2)-CW-V53 position Indication Discharge Valve 1(2)-CW-V56 position Alarm CWOD Pump 1(2) A Lube Water Low Flow 17 18 19 20 21 22 23 24 25 26 27 Alarm Alarm Alarm Alarm Alarm Alarm Alarm Alarm Alarm Alarm Alarm CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump CWOD Pump 1(2) B Lube Water Low Flow 1(2) C Lube Water Low Flow 1(2) D Lube Water Low Flow 1(2) A Motor Overload 1(2) B Motor Overload 1(2) C Motor Overload 1(2) D Motor Overload 1(2) A Ground Current 1(2) B Ground Current 1(2) C Ground Current 1(2) D Ground Current 33 34 39 40 50 52 Alarm Alarm Alarm Alarm Alarm Alarm Unit 1(2) Bearing Lube Pumps Low Pressure LOCAL-REMOTE Switch in LOCAL position CWOD Pump 1(2) A Motor High Temperature CWOD Pump 1(2) B Motor High Temperature CWOD Pump 1(2) C Motor High Temperature CWOD Pump 1(2) D Motor High Temperature I
SD-29 l
Rev. 2 7
Page 68 of 85 l
TABLE 29-4 Page 1 of 2 Annunciators Annunciators CWIP Pump A Trip CWIP Pump B Trip CWIP Pump C Trip CWIP Pump D Trip CW Debris Filter High dP CW Pump Lube Water Flow Low Bearing Lube Water Strainer Differential High CW Trash Rack Diff High Water Box Air Removal Sys Trouble Supervisory System Trouble Tube Cleaning System Trouble CW Disch Pump Motor Overload CW Disch Pump Ground Current CW Disch Motor RTD Temp Hi CW Disch Pmp Lube Water Flow Low CW Disch Pmp Lube Water Press Low Disch Canal Level High/Low Intake Canal Flood Level High Unit(s) 1 and 2 1 and 2 1 and 2 1 and 2 1 and 2 1 and 2 1 and 2 Annunciator Panel Number UA-01 UA-01 UA-01.
UA-01 UA-01 UA-01 UA-01 1
1 and 2 and 2 UA-01 UA-03 1
2 1
1 1
1 and 2 only and 2 and 2 and 2 and 2 UA-05 UA-05 UA-24 UA-24 UA-24 UA-24 1 and 2 UA-24 1
1 and 2 and 2 UA-24 UA-24 I SD-29
.Rev.2 Page 69 of 85
TABLE 29-4 Page 2 of 2 Annunciators Annunciatam Unilt(s)
Tube Sh Press Cath Prot Sys Trouble Turbine Bldg E Cndr Pit Flood Level Hi Turbine Bldg NW Cndr Pit Flood Level Hi Turbine Bldg SW Cndr Pit Flood LvA Hi 1 and 2 1 and 2 Annunciator Panel NWumbe UA-24 UA-28 1 and 2 UA-28 1 and 2 UA-28 SD-29 Rev. 2 -
Page 70 of 85 l
TABLE 29-5 Page 1 of 4 Instrument and Control Setpoints INSTRUMENT TRIP FUNCTION INSTRUMENT INDICATOR/
TRIP SETPOINT AND FUNCTION DESIGNATION RECORDER CW Intake Pump A Lubo Water Flow 1 (2)-SW-FS-1 12 N/A 5.0 to 6.0 gpm Trips CWIP A on Low Flow to Bearings. Ann Pnil UA-01 decreasing CW Intake Pump B Lube Water Flow 1 (2)-SW-FS-1 13 NIA 5.0 to 6.0 gpm Trips CWIP B on Low Flow to Bearings. Ann Pnl UA-01 decreasing CW Intake Pump C Lube Water Flow 1 (2)-SW-FS-1 14 N/A 5.0 to 6.0 gpm Trips CWIP C on Low Flow to Bearings. Ann Pnl UA-01 decreasing.
CW Intako Pump D Lubo Walor Flow 1(2)-SW-FS-1 15 N/A 5.0 to 6.0 gpm Trips CWIP D on Low Flow to Bearings. Ann Pnil UA-01 decreasing Intake Canal Level 1(2)-SCW-LT-285 1(2)SCW-LR-285/
14 to 14-9 Annunciator 'Intake Canal Flood Level High' on Ann. PnI.
CW-LR-761 greater than UA-24 MSL Increasing Dlschargo Canal Level 1(2)-CW-LT-761 1(2)SCW-LR-285/
High 5' Annunciator 'Disch Canal Level High/Low' on Ann. Pnl.
CW-LR-761 Increasing UA-24.
Low 3 decreasing CW 1(2) A-N Debris Filter 1 (2)-CW-DPT-7094A 1 (2)-CW-PDI-519-1 80 inches Annunciator 'CW Debris Filter High dP" on Ann. Pnl. UA-01 Increasing CW 1(2) A-S Debris Filter 1 (2)-CW-DPT-7094B 1 (2)-CW-PDI-520-1 80 inches Annunciator 'CW Debris Filter High dP' on Ann. Pnl. UA-01 increasing CW 1(2) B-N Debris Filter 1 (2)-CW-DPT-7094C 1 (2)-CW-PDI-521-1 80 inches Annunciator 'CW Debris Filter High dP" on Ann. Pnl. UA-01
__increasing CW 1(2) B-S Debris Filter 1 (2).CW.DPT-7094D 1 (2).CW-PDI.522-1 80 inches Annunciator CW Debris Filter High dP" on Ann. Pnl. UA-01 I_
I_ _increasing SD-29 Rev. 2 Page 71 of 85
TABLE 29-5 Page 2of 4 Instrument and Control Setpoints INSTRUMENT TRIP FUNCTION INSTRUMENT INDICATOR/
TRIP SETPOINT AND FUNCTION DESIGNATION RECORDER CW Disch Pump Lube Header Press 1 (2)-CW-PS-1 131 N/A 27 to 33 psig Starts Auto Lube Water Pump decreasing 1(2)-CW-PS-1 132 N/A 32 to 38 psig Annunciator ICW Disch Pump Lube Wtr Pressure Low' on decreasing Ann. PnI. UA-24 CW Disch A Pump Lube Water Flow 1 (2)-CW-FS-1 117 N/A 6.5 gpm Trips CWOD Pump A on Low Flow to bearings.
decreasing Annunciator 'Lube Water Low Flow' on Ann. PnI. UA-24 CW Disch Pump B LubeWater Flow 1(2)-CW-FS-1120 N/A 6.5 gpm Trips CWOD Pump B on Low Flow to bearings.
decreasing Annunciator 'Lube Water Low Flow' on Ann. PnI. UA-24 CW Disch Pump C Lube Water Flow 1 (2)-CW-FS-1 123 N/A 6.5 gpm Trips CWOD Pump C on Low Flow to Bearings.
decreasing Annunciator 'Lube Water Low Flow' on Ann. PnI. UA-24 CW Disch Pump D Lube Water Flow 1 (2)-CW-FS-1 126 N/A 6.5 gpm Trips CWOD Pump D on Low Flow to Bearings.
decreasing Annunciator *Lube Water Low i low' on Ann. PnI. UA-24 I SD-29 I
Rev. 2 1
Page72of85
TABLE 29-5 Page 3 of 4 Instrument and Control Setpolnts INSTRUMENT TRIP FUNCTION INSTRUMENT INDICATOR/
TRIP SETPOINT AND FUNCTION DESIGNATION RECORDER Hi Turbine Bldg CW Pipe Pit Flood 1X-LSH-3106 (E)
N/A 10' Annunciator "Turb Bldg CW E Cndr Pit Flood Level Hi' on Level - Unit 1 1X-LSH-3114 (NW)
Increasing Ann. PnI. UA-28.
Annunciator Turb Bldg CW NW Cndr Pit Flood Level Hi' on Ann. Pnl. UA-28.
Annunciator "Turb Bldg CW SW Cndr Pit.Flood Level Hi' on Ann. PnI. UA-28.
Hi-Hi Turbine Bldg CW Pipe Pit Flood 1X-LSHH-3107(E)
N/A 60" CW Intake Pumps High Flood Level (60") Trip Signal Input.
Level - Unit 1 1X-LSHH.3115(NW) increasing 1X-LSHH-3112(SW)
HI-Hi Trip Turbine Bldg CW Pipe Pit 1X.LSHH-3108(E)
N/A 108" Trips CW Intake Pumps on Combination High-High Flood Flood Level - Unit 1 1X-LSHH-3205(NW)
Increasing Level of 108-and a Confirmed High Flood Level of 60'.
1 X-LSHH-3113(SW) i Hi Turbine Bldg CW Pipe Pit Flood 2X-LSH-3106 (E)
N/A 10-Annunciator "Turb Bldg CW E Cndr Pit Flood Level Hi' on Level - Unit 2 2X-LSH-3109 (NW) increasing Ann. Pnl. UA-28.
Annunciator "Turb Bldg CW NW Cndr Pit Flood Level Hi' on Ann. Pnl. UA-28.
Annunciator 'Turb Bldg CW SW Cndr Pit Flood Level Hi" on Ann. PnI. UA-28.
Hi-Hi Turbine Bldg CW Pipe Pit Flood 2X.LSHH-3107(E)
N/A 60" CW Intake Pumps High Flood Level (60") Trip Signal Input.
Level - Unit 2 2X-LSHH-3112(NW) increasing 2X-LSHH-3115(SW) 2X-LSHH-3108(E)
N/A 108" Trips CW Intake Pumps on Combination High-High Flood Hi-Hi Trip Turbine Bldg CW Pipe Pit 2X-LSHH-3113(NW)
Increasing Level of 108" and a Confirmed High Flood Level of 60-.
Flood Level - Unit 2 2X-LSHH-3205(SW)
SD-29 l
Rev. 2 l
Page 73 of 85l
TABLE 29-5 Page 4 of 4 Instrument and Control Setpolnts INSTRUMENT TRIP FUNCTION INSTRUMENT INDICATOR/
TRIP SETPOINT AND FUNCTION DESIGNATION RECORDER Tubesheet Pressurization High Filter 1(2)-TSP-PDS-1012 N/A 15 psid Annunciator 'Tube Sht. Press. Cath. Prot. Sys. Trouble' on Differential Pressure 1(2)-TSP-PDS-1013 Increasing UA-24.
Tubesheet Pressurization Low System 1 (2)-TSP-PS-1016 N/A 20 psig Annunciator "Tube Sht. Press. Cath. Prot. Sys. Trouble' on Pressure decreasing UA-24.
Tubesheet Pressurization High Inlet 1(2)-TSP-FSA-1017 N/A 1 gpm Annunciator 'Tube Sht. Press. Cath. Prot. Sys. Trouble' on Tubesheet Flow increasing UA-24.
Tubesheet Pressurization High Outlet 1(2)-TSP-FSA-1018 N/A I gpm Annunciator 'Tube Sht. Press. Cath. Prot. Sys. Trouble' on Tubesheet Flow Increasing UA-24.
SD-29 Rev. 2 Page 74 of 85
FIGURE 29-1 Circulating Water System Unit 2 SD-29 Rev. 2 Page 75 of 85
FIGURE 29-2 Debris Filter Cross Section EXHAUST FROM LP TURBINE OF 2 F.W. HEATERS BACK WASH-PRESSURIZED.
TUBE INLET SHEET DISCHARGE VALVE FILTER I
SD-29 I
Rev. 2 l
Page 76 of 85 l
FIGURE 29-3 AMERTAP System Cross Section t
VATER INLET WAtER mUTLET I
SD-29 Rev. 2 I
Paae 77 of 85 I Paoe77of85I I
FIGURE 29-4 AMERTAP System Unit 2 BALL STRAINERS RECIRCULATION PUMPS COLLECTOR BASKETS CONDENSER INJECTORS CV FRY34 2B 2A SD-29 I
Rev. 2 I
Page 78 of 85
FIGURE 29-5 AMERTAP Ball Collection Strainer AIRFBIL-SECTION THROTTLE SPONGE BALLS BEING CAUGHT ON SCREENS IN NORMAL OPERATING POSITION I SD-29 Rev. 2 Page 79 of 85
FIGURE 29-6 Intake Canal General Arrangement APPROX LOCATION OF SNOWS MARSH CHANNEL RANGE SD-29 Rev. 2 l
Page80of85l
Cl) 0 CO~
133 DIKE CD rm a
0 Co CD 3 m (Dr m QI
-5 ID 0
)CD CD, CASWELL BEACH ATLANTIC OCEAN (0
ID co (D
00 CO)
En
FIGURE 29-8 Caswell Beach Pumping Station Layout I -
cz l SD-29 I
Rev. 2 l
Page 82 of 851
(0 (D
c) 0tC)nm SDm
_.Co CO v
CD la-o 5 G) toCD Cj) 0 0
aU CD X
CD (C) 0 co Cn
FIGURE 29-10 CWIP Characteristic Pump Curve 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 SD-29 Rev.2 Page 84 of 85
FIGURE 29-11 CWOD Pump Characteristic Pump Curve 0
x 16 W 120 LU CO)
E IY 0
4 Lu 35 UI.
3OZ 2n 25 z 30 60 90 120 150 180 210 240 GALLONS PER MINUTE X 1,000 SD-29 I
Rev. 2 I
Page 85of 85