ML19206B381

Preliminary Licensing Rept for Westinghouse Decay Heat Removal Sys

ML19206B381
Person / Time
Site:	Crane
Issue date:	05/01/1979
From:	WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:
Shared Package
ML19206B380	List: ML19206B379 ML19206B381
References
WP-TMI-003, WP-TMI-3, NUDOCS 7905090339
Download: ML19206B381 (29)

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WP-TMI-003 i..

PRELIMINARY LICENSING REPORT FOR WESTINGHOUSE DECAY HEAT REMOVAL SYSTEM j

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i EFFECTIVE REVISED i

CATE PAGE 1 0F DATE WE STINGHOUCE FO RM NSO

• A 1014 790509033'/

1 ef NSD REV.

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CccrNTs I.

I'CRODUCTION II.

SYSTEMS DESIGN l

III.

MECHANICAL DESIGN IV.

CONTROL AND INSTRUMENTATION V.

ELECTRICAL DESIGN VI.

RADIATICN A':ALYSES VII.

QUALITY ASSURANCE w

E F F E CTIVE REVISED DATE PAGE 2 0F DATE W E S TINGHO'JSE F O m v NSO P A 1014

?.[ N S D REV.

I.

INTRODUCTION This document describes the designs, safety aspects and quality assurance program for systems to be installed at TMI Unit 2 to supolement the plant's existing systems for the removal of decay heat.

Specifically, these systems consist of:

A.

The Westinghouse Decay Heat Removal System which takes suction from the plant's decay heat line and returns cooled reactor coolant flow to the plant's core flooding lines.

B.

'The Westinghouse Decay Heat Closed Cooling System whi,ch provides fresh water cooling flow to the Decay Heat Removal System.

C.

Piping connections from the Westinghouse Decay Heat Closed Cooling System to the plant's Nuclear Services River Water System.

D.

The electrical systems and control and instrumentation required for operation of the above systems.

1 E.

Piping and valving which could be used to provide for an additional heat removal system at a later date.

The Westinghouse designed systems are to be mounted on b skid located adjacent to the west wall of the TMI Unit 2 Fuel Handling Building except for the necessary piping connections to the Nuclear Services River Water System, and the piping connections through the Fuel Handling Building. The location of the skid, outside the Fuel Handling Building, was chosen only after very careful consideration of other locations and after extensive discussions a=ong Westinghouse, General Pablic Utilities and the NRC staff.

A set of design criteria WP-TMI-004 for the systems has been evolved and has been transmitted separately to the Staff.

This document describes only the Westinghouse designed systems.

It does not address control and protection logic or systems operation for those systems which interface with the Westinghouse decay heat removal systems.

In recognition of the fact that these systems are intended for the possible removal of post accident decay heat, they have been designed, as far as is practical within the time constraints, according to the relevant codes and standards which would normally apply. The systems are considered to be for temporary use only.

II.

SYSTEMS DESIGN A.

3ack-Up Decay Heat Rem: val System } C)] 1.0 System Function The function of the Westinghouse Decay Heat Removal System is to provide core cooling capability for the Three Mlle Island Unit 2 Nuclear Power Generating Statiun. I E F F E CTIVE REVISED DATE PAGE 3 0F DATE W(5TINGMcVSE Fo8me NSD P A 1014

W NSD HEV. The specific function of the Westinghouse Decay Heat Removal System is to remove heat frca the reactor coolant such that the Reactor Coolant System can be brought to and =aintained at a cold shutdown condition. Precluding any gross flow restrictions within the core, this system provides a sufficient flow through the core, such that the reactor coolant remains subcooled. An integral Westinghouse Decay Heat Closed Cooling Water System is provided specifically for the purpose of transporting heat f rom the system cooler and the pu=p seal coolers, to the Nuclear Service River Water System. These systems interface with the existing Decay Heat Removal System m. (B&R Drawing 2026), the Nuclear S(rvices River Water System (3&R Drawing 2033) and both on-site and off-site electrical power. 2.0 Design Bases The following design bases are applicable for the Westinghouse Decay Heat Re= oval System and the Westinghouse Decay Heat Closed Cooling Water System. The use of existing nuclear grade pu=ps and coolers, similar to the existing equipment at IMI Unit 2 was dictated by the requirement to have the systems available for installation cn a short time scale. Due to the relatively high radiation levels vibhin the Fuel Handling Building and the Auxiliary Building, and the low probability that these areas could be decontaminated within a resonable time frame, these preferred locations were deemed unavailable for the system's equipment. Consequently, the majority of the systems are to be located in the yard area adjacent to the west wall of the Fuel Handling Building at grade elevations of 305 feet. As a consequence of locating the Westinghouse Decay Heat Removal Pump at the 305 foot elevation, the pu=p flow must be restricted to reduce the required NPSH and suction line fricticn losses. To ensure adequate NFSH f r the pu=p, a predetermined water level cust be maintained in the pressurizar or in the refueling canal should the reactor vessel head be re=oved at some futare date. Also to ensure that the water level in the pressuricer or refueling canal is adequate to satisfy the required NPSH, redundant pressure instrumentation ir required in the pump suction header. This instrumentation provides an accurate indication of the available static head when the system is not operating, or the actual suction pressure when the system is operating. Since the syste=s are designed to supplement the plant's existing systems for the re= oval of decay heat, the single failure criteria is not directly applicable. The systems are designed basically for only one functicn: to obtain and maintain the Unit 2 reactor in a safe cold shutdown condition. In order to accet=odate this single function and satisfy the urgency for installed and operable systems within a short time frace, the i EFFECTIVE REVISED DATE PAGE 4 0F CATE nesTmosovse roav Nso FA ici4 9I cJ

W NSD REV. design approach was to keep the system as simple as possible. For example, a mini =um nu=ber ot valves, and the use of flow restricting orifices rather than flow control valves was a basis for the design. The design includes shielded piping connections to allow for possible future additions. 3.0 Design Assu=ptions The following design assu=ptions are applicable. I*t Pressuri:er power operated relief valve can be ope.ned and maintain in an open position. Pressurizer heaters and level indications are conservatively assumed not available. The makeup system is svailable for maintaining the desired water level in the pressurizer during any operationg of the Westinghouse Decay Heat Removal System, and for any required chemical additions to the reactor coolant. The Westinghouse Decay Heat Removal System can be operated with the pressurizer water solid, however, this would require great care to ensure that the system is not subjected to unacceptable over pressure transieats.

4.0 System Description

4.1 General The Westinghouse Decay Heat Re= oval System is shown on Westinghouse Electric Engineering Flow Diagram W-TMI-1019. The principle components of the system are two Westinghouse Lecay Heat Removal pumps and one Westinghouse Decay Heat Removal Cooler. The performance characteristics of these co=ponents are cimilar to the existing components. There are also fifteen motor operated gate valves, in the 6 to 12 inch size, associated with the system. The major system components are count.d on skids which will be located in the yard area adjacent to the west wall of the Fuel Handling Building. Three lines will be routed from the skid through penetra-tions in the west wall of the Fuel Handling Building. Inside the Fuel Handling Building, these three lines are routed to the designated connection points on existing Decay Heat Removal System lines. These connecticn points are adjacent to the containment piping penetration area. One of these three lines serves as the suction line for the system pumps and it connects to the-existing decay' heat drop line immediately downstream of existing Decay Heat Re=cval System isolation valve, DEV-3. The other two lines serve as discharge headers for the Westinghouse Decay Heat Removal System, and thr" connect to the existir ; injection lines inmediately downstream of exiscing isolation valves DH-V-4A and 4B. 2ach of these three new lines contain a motor operatec <,n E F F E CTIVE R EVi!E D O f U L DATE PAGE 5 0F DATE L AE STINGMouSE S o AM NSD P A 1014

W NSD REV. isolation valve as close as practical to the connection points to the existing lines. Each of these three r2w lines also contain a =otor operated isolatian valve located i= rec.1ately outside the Fuel Handling Building in a concrete valve compartment. Including existing va?ves, there are six cotor operated ceries valves between the Reactor Coolane system hot leg and the Westinghouse Decay Heat Removal System purp's suction flange. There are five motor operated series valves and two check valves between the pump discharge flange and the Reactor Coolant System. t'h All valve stem leak-of f s, pump seal leak-of f s and. thermal relief valves are connected to a com=cn vent header which is rcuted to the drain header in the Fuel Handling Building. Flange connections are minimized and welded joints are utilized to the maximum extent possible. A. Westinghouse Decay Heat Removal Pumps (DEA-P-1A and DHA-P-15) The pumps have operating characteristics similar to the existing TMI Unit 2 pu=ps. The pumps (Table 1) are single stage centri-fugal pu=ps rated at 3000 gpm each at a total discharge head of 350 feet. For NPSH consideration, the system is provided with flow restricting orifices which limit the =aximum runout flow of each pump to a value between 1750 and 2000 gpm. The pumps are located at the 305 foot grade elevation in the yard area adjacent to the west wall of the Fuel Handling Building. The two pumps are arranged in parallel with appropriate suction and discharge motor operated valves to permit the isolation and termination of any excessive pu=p seal leakage. A single mini-flow path is provided for the two parallel pu=ps. This miniflow line is rcuted frem the diecharge of the cooler to the co==on pump suction header. Pressure transmitters are connected to the pump suction header to provide re=ote indicmtion of the available NSPH with a los suction pressure alarm. The function of the pumps is to circulate reactor coolant water thrcugh the cooler to the reactor vessel via two existing injection headers, through the core and back to the pump suction header via the existing decay heat drop line. 2 3. Westinghouse Decay Heat Re= oval Coolers The function of the cooler is to transfer heat from the Westinghous Decay Heat Re= oval System to the Westinghouse Decay Heat Closed Cooling Water System. The cooler is a four pass shell and tube .yp e aat exchanger with the reactor coolant on the tube side. ihe snell is designed in'accordance with the ASME Code Section III-D and ehe tubes in accordance with Section III-C. The cooler is located at the 305 foot grade elevation. ')f b cJ EFFECTIVE REVISED DATE PAGE 6 0F DATE WE STINGHoLSE FORM N3o P A 1Q14

aY NSD R E V. 4.2 Mode of Operations In the event tha t the Westinghouse D2 cay Heat Renoval System were to be put into operation, the Reactor Coolant system must be below approx 1:ately 400 psig to prevent the lifting of thermal relief valves. The pressurizer sheuld be at least 1/2, and preferably 3/4 full to ensure adequate NPSH for the pump in the event that the reactor coolant is at saturated conditions. The pressurizer level must also allow for shrinkage of the reactor coolant as the temperature is reduced by the cooler. When the RCS pressure is below the 400 psig D.'

ut-in pressure, the existing pressurizer spray lines which branch f rom the existing injection headers upstream of DH-V-4A and 43 can be used for RCS depressurization, if the manual valves in these lines are ope:.ed.

The Westinghouse Decay Heat Removal System can deliver flow to the pressurizer if the flow path through the existing pressurizer spray line is =ade available. If the pressurizer spray line flow path is not available, the pressurizer power operated relief valve can be used to vent the pressurizer down to an acceptable pressure level. Since the pressurizer can act as a surge tank, it is preferred that the pressurizer vents should renain open during long term operation. One pu=p should be aligned for miniflow operation and the cotor operate d isolation valve in each of two injection headers should be closed. The one pump aligned for miniflow operation would be started and the leaktightness of all components verified to the maximum extent possible Af ter the leaktightness and operational integrity of the systen was verified, the five series =otor operated valves in the suction line from the Reactor Coolant System hot leg to the pumps would be opened. Next, one of the two parallel flow paths from the one operating pu=p to the reactor vessel would be established by opening four series motor operated valves. The remote indicated flow and suction pressure would be observed and the systes resistance verified to be acceptable prior to opening the second flow path to the reactor vessel. The second flow path would be established by opening four serics motor operated valves. The suction pressure would be checked tc verify that adequate NFSH was available to -he operating pump. s .? on2 7_r'_)LU EFFECTIVE REVISED DATE PAGE 7 0F DATC wasTisosoOSE FC Au NSO n told

i Yi NSD REV. TABLE 2.0 WESTINGHOUSE DECAY HEAT REMOVAL COOLER QUANTITY SHELL TU3E Design p'ressure 175 psig ,,600 psig Design te=perature 350 degrees F 350 degrees F 6 6 Mass ficurate 1.5 x 10 lb/sec 1.5 x 10 lb/sec Te=perature In 105 degrees F 140 degrees F Te=perature Out 124.3 degrecs F 120.7 degrees F b Heat transfer (Q) 28.95 x 10 btu /hr Material Carbon Steel Stainless Steel Seismic Design Class 1 Code / Class ASME III-D ASME III-C I b') 'l EF F E CTIVE REVISED ) r-] 05 TE PAGE 3 0F DATE W E ST I N G H O L S E F O A V N.O P A 1014

T NSD R E V. 6.0 Tests and Inspections Periodic tests will be perforced to determine the operational integrity and leak tightness of the Westinghouse Decay Heat Removal System. Active components, such as valves and pumps, will be periodically cycled to demonstrate operation. Each pump can be periodically operated on a miniflow and, if desired, multiple head flow pump characteristics can be obtained by installing a epool piece with a variable orifice across the suction anc dis-charge lines provided for possible future additions to the system. "7. 0 Instrumentation Application t. The instrumentation in the system provides measure =ents which are used to indicate and alarm process variables. The following pro ess variables are measured and a signal is a. c transmitted that will provide indication in the control panel located in the control trailer. 1. Pump suction pressure 2. Pump suction te=perature 3. Cooler inlet pressure 4. Cooler discharge pressure 5. Cooler discharge temperature 6. Injection flow B. Westinghouse Decay Heat Closed Cooling Water System 1.0 System Function The function of the Decay Heat Closed Cooling Water System is to provide cooling water to the Westinghouse Decay Heat Removal System. Specifically, cooling flow is provided to the Westinghouse Decay Heat Removal Cooler and the Westinghouse Decay Heat Removal Pump's ] seal cooler. Heat is transferred from the Westinghouse Decay ( Heat Closed Cooling Water System to the Nuclear Services River i Water System. 2.0 Design Basis l Because of the extremely short time available fcr design, procure-cent, and construction, this system is not cptimally designed. However, the system and all cc=ponents meet or exceed design l requirements. l The system consists of an independent clcsed water loop. The F heat gained in the system's cooler is transferred to the Nuclear Services River Water System, which supplies river water through l EFFECTIVE REVISED qqd DATE PAGE 9 DF DATE 9y+3 /u 6 w-A E STINGHot SE F o R%? NSo P A 1014

W NSD REV. either of the two separate 100 percent capacity circuits. An elevated surge tank is required in each loop to accc=modate changes in system water volume due to temperature variations and to serve as a reservoir to make-up for system losses through normal leakage. The surge tank is Ic.cated to provide the required NPSH at the pump suction. A chemical feed connection is provided for the addition of chemical inhibitor for corrosion protection. Th e piping system is designed, fabricated, ins, acted, and erected in accordance with ANSI B31.7 with all ecmponent's" fabricated from carben or stainless steel. Seismic classification of the system is Class I. The system is designed to detect leakage frem the Westinghouse Decay Heat Removal System into the system. l Isolation valves are required on all equipment. System leakage and equipment drainage is collected and returned to the plant. The Westinghouse Decay Heat Closed Cooling Water Pu=p is electrically powered from 480V bus 2.44 with backup power from a standby diesel generator.

3.0 System Description

The Westinghouse Decay Heat Closed Cooling Water System is shown schematically on ficw diagram V241-1017 and the pump and major system components are listed in Table 1. System operation is required when the Westinghouse Decay Heat Removal System is needed for plant cooldown. The Westinghouse Decay Heat Closed Cooling Water System ce=penents are located en a skid, sitting on grade level. The =ain ficw path from the discharge of the pump is to the cooler. Branch 11"; _com the main dir, charge line supply ecoling water to the Wescinghouse Decay Heat Removal Pumps. The return flows from the equipment are joined to a cc= mon header and directed to the decay heat service cooler where the heat is transferred to the Nuclear Service River Water System. The cooled flow is returned to the suction side of the pump for recirculation. The total ficw and branch flow rates are set during pre-operational testing to ensure proper ficw rates when system operation is required. A connection is provided in the system for the addition of chemical inhibitor for corrosion protectica. The inhibitor is added manually when chemical analysis of the coolant indicates a concentra icn which is below the speficied limit. o g t; r ,hb"~ E F F E CTIV E REVISED CATE PAGE 1CDF DATE WEST!NGHoVSE S o au NSo P A 1C14

Yi NSD sev. For the plant cooldown operation, the pump is remotely operated from the remote control panel located in the control trailer. After the river water flow through the decay heat service cooler has been established, the system is put into operation prior to operation of the Westinghouse Decay Heat Removal Pumps. 4.0 Safety Evaluation The Westinghouse Decay Heat Closed Cooling Water System, by utilizing a closed loop system, provides a double barrier between the decay heat removal system and the river water to prevent the direct release of radioactivity to the environment. A radiation detector is provided to monitor the level of radidactivity in the system at the outlet of the Westinghouse Decay Heat Removal Cooler. A radiation level indicator and high radiation level alarm are located in the control trailer. If radioactivity is detected, operation can be halted and the cooler isolated. The components of the Westinghouse Decay Heat Closed Cooling Water System are designed in accordance with codes and standards as shcwn in Table 1. Welded construction is used whenever practical in the system to minimize the possibility of leakage. 5.0 Tests and Inspection The pump and major components of the system are subjected to manufacturer's shop tests including hydrostatic and performance tests. The system piping is subjected to an initial service leak test in accordance with ANSI B31.7 prior to initial operation. In addition, the completed system is subj ect to pre-eperational testing. Pump seals, valve packing, flange gaskets, heat exchange:s, and relief valves are subjected to inspection for leakage. A sample connection is provided to permit =anual sampling for chemical and radiological analysis in the closed loop of the system. ~ The results of the sa=ple analysis determine the need for chemical addition er other corrective action. 6.0 Instr' centation Application Instrumentation and controls are provided to control and tonitor the operation of the system as well as the Individual equipment performance. Remote control and indication is located in the remote control trailer. The inlet and outlet temperatures of the Westinghouse Decay Heat Removal and decay heat service coolers are indicated on the control panels located in the control trailer. c) 7) hO E F F E CTIVE REVISED CATE PAGE 11 0F DATE L A E S T i a.G H o uS E F o R M,9 NSO P A 1014

W NSD aEv. High temperature at the outlet of the decay heat service cooler is alarmed. The closed cooling water flow, with high and low alar =s, is indicated in the ccntrol trailer. The surge tank level is also indicated in the control trailer,with associated high and low level alarms. C. Nuclear Service River Water System 1.0 System Function The existing Nuclear Service River Water System has been modified to provide cooling water for the Westinghouse De, cay Heat Closed Cooling Water System. In addition, provisions haVe been made for future additions to the system. 2.0 Design Basis This section discusses only the modifications made to the ex _ning 4 Nuclear Service River Water System. The modifications do not degrade the existing system performance because adequate water supply is available due to the unusually low demand for flow under the present circumstances. Connections from each Nuclear Service River Wa'ter discharge header and to the return line are made either in the river water pump house or between the river water pump house and fuel handling building. Each connection branches off; one line leading to the decay heat service cooler and the other line valved closed with a blind flange end connection to facilitate future additions to the system. The modifications are required to provide cooling flow to the decay heat service cooler. Two redundant flow paths from the existing Nuclear Service River Water System are provided.

3.0 System Description

The modified section of the system is shcwn sche =atically on flow diagram WTMI-1017. Water flows from one of two Nuclear Service River Water System discharg; li:.as, through the decay heat service cooler, and back to the return header. The desired flow is obtained by setting a throttle valve. All operations involved are manual. l Indication of the service flow ic provided in the control trailer. 4.0 Safety Evaluation The safety margin in the Nuclear Service River Water System is not reduced since adequate flow is available in the plant's current situation. 5.0 Instrumentation A flow indication of the ficw to the decay heat service cooler, with high alarm, is provided in the control trailer. l 9I ,f f cJ i EFFECTIVE REVISED CATE PAGE12 0F DATE W E 3?1NGHouSE S C R M NS D P A 1014 j /

i ?.! N S D R E V-TABLE 1 The system design pressure and temperature are 150 psig and 200 degraes F, respectively. The actual parameters for the individual ccepor.ents are listed below. These parameters meet or exceed system requirements. 1. Westinghouse Decay Heat Closed Cooling Water Pump: Design, Pressure 150 psig Design Temperature 200 degrees F Design Flow 3000 gpm Heat 3 design flow 175 feet NPSHr @ design flow 12 feet Material Stainless steel Drawing Gould's L23359601, Rev. 5 Pump curve Gould's A-23361 Ccde: ASP.E III 2. Decay Heat Service Cooler Shell Tubes Design Pressure 150 psig 600 psig Design Temperature 350 degrees F 400 degrees F Flow 1,740,000 lb/hr 1,110,000 lb/hr Inlet Temperature 95 degrees F 139 degrees F e Outlet Te=perature 105.5 degrees F 121 degrees F Pressure Drep 20 psi 15 psi Material Carbon Steel Stainless Steel Drawing Jas. Oat & Sons, 5133, rev. 5 Data Sheet Jas. Oat & Sons, for _4 p.o. 157515 Code ASME VIII ASME III, Class C r\\ Q EFFECTIVE REVISED 9 bV DATE PAGE 13 CF D ATE L. msr:NosoUSE FORM N$o PA 1014

i E NSD a E v. TABLE 1 (CONTINL'ED) 3. Uestinghouse Decay Heat Closed Cooling Water Surge Tank Design Pressure 300 psig Decign Temperature 250 degrees F

Volume, Approx. 675 gal.

Material Stainless Steel Drawing W 1142E06, sub. 5 Code ASME, Class 3 i 4. Runcut Orifices Design Pressure 150 psig Design Te:perature '600 degrees F ~ Orifice #1 connections 8" 150# FJ flanj;es Orifice #2 c:nnections 14" 150# RF flanges Orifice #1 ID 5 1/4" Orifice #2 ID 6 3/4" 1 n( i m 9] l ' EFFECTIVE REVISED L-CATE PAGE 110F DATE W E ST:NG H OUSE F O R M NS D P A 1014 ii

S$( NSD REV. III. MECHANICAL DESIGN A. k*estinghouse Decay Heat Removal System The system consists of a primary cooling system with a heat exchanger, redundant pumps, isolation valves, and associated piping conaected to the existing plant Decay Heat Removal System. The connections from the existing plant Decay Heat Removal System are an 8 inch branch connection to the single 12 inch from the Reactor CQolant System with 6 inch branch connections to each of the two 10 inch lines returning to the Reactor Coolant System. The system lines within the Fuel Handling Building consist of a single 8 inch line pencerating the boundary of the building with two 6 inch return lines. The lines are sealed at the Fuel Handling Building wall, terminate in bolted flanges or weld caps for attachment to the remainder of the system and contain redundant electrically operated isolation valves with one valve in each line located outside the building. The lines are Schedule 40, seamless, austenitic piping, type 304, with butt welded fully radiographed con-nections. The piping is designed and constructed to ANSI B.31.7 Class 2 and provided with suitable supports and restraints to accommodate CBE Seismic accelerations within Design Stress limits. The lines penetrating the building are connected by 'means of weld-o-lets to a 12 inch line to the system components and two 10 inch return lines. The weld-o-lets are attached to the existing Decay Heat Removal System pipes with full penetration attach =ent welds with liquid penetrant examination of the root and final weld passes in lieu of radiographic examinations. The system major components are located on a skid assembly. The skid assembly consists of a weldeu platfor= 17 f t. long by 14 ft. wide fabricated from 10 inch wide flange beams. On the skid assembly, the 12 inch suction line branches to two vertical Ingersoll Rand Decay Heat Removal Pu=ps with a 12 inch flanged bottom suction connection and an 8 inch, flanged, tangential discharge. Motor operated, flexible wedge gate valves are butt welded into the pipe lines on either side of the pumps to provide complete isolation capability for each pump. The pump discharges are connected to a single, flanged, 14 inch inlet to the tube side of a horizontally mounted Atlas Heat Exchanger. The skid piping system is austenitic stainless steel, type 304, seamless piping, schedule 40 with fully radiographed, butt welded connections. The skid terminal connections, as well as connections to the pumps and the Heat Exchanger, are by means of flanged, flexatallic joints using 300 lb. pressure rating weld neck flanges. The skid piping system is designed and constructed to ANSI 331.7 Class 2. Analyses have been performed covering steady state thermal stresses and the system is designed to accom=odate CBE accelerations within design stress limits. The system pumps are vertical Ingersoll-Rand Decay Heat Removal Pu=ps with nominal design conditions of 3000 gpm, and a T.D.H. of 350 ft. at r. EFFECTIVE REVISED G\\O 15 DATE PAGE 0F DATE q {3 b' WE ST'NG Hot S E F o A %t NSo # A 1014

{ T NSD REV. 1780 rpo. The pumps are designed ar.d constructed to the ASME Code Section III, Class 2, with a design pressure of 600 psig at 350 degrees F. A Durametallic mechanical shaft seal is used with an external seal cooler supplied with external cooling from the Closed Cycle Decay ileat Removal System. The pump motor is an Allis Chalmers Induction motor of 400 HP rating with a service factor of 1.15. The motor has Class F insulation and operates with a 4000 volts, 3 phase, 60 hertz power supply. The heat exchanger was manufactured by the Atlas Industrial Manufacturing Company. The Reactor Coolant fluid is confined to the tube side of the udit which consists of austenitic stainless steel headers, a carbon steel clad tube sheet and type 304, U-tubes which are rolled'und seal welded to the tubesheet. The tube side of the unit is designed and constructed in accordance with the ASME Code, Section III, Class 2, 1971 Edition. Tube side design conditions are 600 psig at 350 degrees F. The shell side of the unit is carbon steel and is designed and constructed in accordance with Class 3 of the ASME Code, Section III. All main nozzle l connections to the Heat Exchanger are 14 inch raised face weld neck flanges, using 600 lt. pressure class flanges on the tube side and 150 lb. pressure class flanges on the shell side. The shell side design conditions are 175 psig at 350 degrees F. The =ain isolation valves used in the lines to and fhom the components are all Westinghouse =anufactured, motor operated gate valves. These valves are designed and constructed in accordance with Class 1 require- =ents of the ASME Code, Section III, with a de~ sign pressure of 600 psig at 400 degrees F, and are 300 lb. pressure rated units which are butt welded to the pipe lines. The valves enploy Limitorque motor operators with Class B insulation. B. Decay Heat Closed Ccoling System The Westinghouse Decay Heat Closed Cooling Systen consists of a heat exchanger, pu=p, accumulator tank, isolation valves, and assorted piping combined to form the cooling circuit for the Westinghouse Decay Heat Removal System. The system is connected to the decay heat removal tube side of the heat exchanger via the 14" ASA 1501 flanged connection reduced to a standard 1 8" carbon steel line. This line contains an 8" motor operated gate valve for isolation upstream of the Decay Heat Service Cooler. The system is driven by a centrifugal pump having a 14" ASA 150# flanged suction side and 12" ADA 1500 discharge side. The discharge line again is reduced to an 8" line which contains another 3" motor operated isola-tion valve. This line also contains this system relief valve and piping. The line then returns to the Decay Heat Removal cooler via a step-up connection to a 14" ASA 1509 flanged joint. The systen also contains an accumulator tank which is skid =cunted as stated earlier and is connected into the Decay Heat Closed Cooling Water piping via a 2" sch. 40 ccrbon steel pipe on the suction side of the pump. i EFFECTIVE REVISED DATE PAGE 16 0F DATE r... wc sm.c s o vs? r o A M NSo P A 1014 ]

W NSD R E V. The accumulator has level gauges and a top air vent which is radiation coni to red. As noted on che attached specification sheet, the entire system neets ASME Class 3 requirements or better. Connection to the 36" RW line will be by an 8" carbon steel sch. 40 line which will circulate through the tube side of the Decay Heat Service Cooler. The 8" Nuclear Service River Water System line will contain an 8" ASA 150# butterfly valve, manually operated with self locking gears for flow control. The discharge line from the cealer is an S" pipe which runs through the shield wall. This line will contain another 8" =anual operated gate valve and relief valve for protection outside the shield wall and prior to return into the 30" Nuclear Service River Water Systen return line. The 30" return line connects ac the mechanical draft ecoling tower which has radiation monitoring equipment. The piping specification for the river water lines wculd be ASTM-A-134 electric fusion welded - A-233 Grade C of 1/2" nominal wall. All pipe is shop coated for underground service with hot coal tar enamel and asbestos felt per AWUA Spec. C-203. SKID MOUNTED ECUIPMENT DESIGN DESCRIPTION 1. Cooler manufactured to ASME Section VIII for the shell and III-C for the tubes with an 8" sch. 40 inlet / outlet to the tubes and 14" ASA 1500 inlet & outlet to the shell. (Design shell tube 2. Pump is =anufactured to ASME Section III Class 3 with a 14" ASA 1500 inlet and 12" ASA 150# putlet. Both pump and cotor are counted on a unitized skid. (Design 150 psig @ 200 degrees F) I 3. Accumulator tank is manufactured to ASME Section III Class 3 of stainless steel construction. (Design 300 psig 0 250 degrees F) 4 8" :otor operated gate valves of carbon steel construction with flanged ends manufactured to ASME Section III Class 2 with an ASA 3001 rating, f 5. Piping is standard wall thickness of 0.375" or better on all 3, 12, and 14 inch lines with flanges, reducers, and fitting of ASA 150# or better to match egiuptent connections. 6. Relief valve is of flanged connections, self accuated and set at 150 psig. EFFECTIVE REVISED DATE PAGE 17 DF DATE WESTINGMovSE c oRY NSC P A 'Q14

i W NSD R E V. IV. CONTROL AND INSTRDENTATION Instrumentation is provided to measure pressures, temperatures, and flows at those points in the systems required for continual or periodic evaluation of system performance and to allow inference of conditiens in the =ain reactor loops and vessels. All measurements are displayed on one of three control panels in the control trailer. In addition, provisions have been made (via terminals) for later duplication of the displays on one or more separate panels located remote from the trailer. Redundant measure =ents and displays are provided for each appropriate parameter and are separated where appropriate to coincide with the A and B fluid system, pump, and valve redundancy. Additionally,'two measurc=ents of Westinghouse Decay Heat Removal Syste= Pump inlet temperature (reactor outlet te=perature) are provided for each pump. Independent power sources are provided for the Train A and B measurements. The Train 3 power source feeds the Decay Heat Closed Cooling Water Sy=ce: =easurements. The instruments selected are, as much as possible, the same manufacture, =odel, and principle as the instruments used in IMI Unit 2. Instrc=ents are qualified by similarity to previously qualified =cdels. No automatic controls or interlocks are provided. The following lists the parameter =easurements provided, the redundancy provided, the expected use of the information, and any special features of the instrument channel. Pu=p bearing and stator temperatures are measured to verify the condition of an operating pump. Redundancy is not provided on a per-pu=p basis but the "A" pump =easurement channels are separated from the "B" pump channels. The normal practice of reading the hottest of several (4) stator winding RTO's is used, thus only one stator tempe ature per pump is displayed. The bearings temp sensors (furnished with the pump) are chromel-constantan ther=occuples and the stator sensors are 10 ch: copper RTD's wound into the stator. Westinchouse Decav Heat Closed Cooline Water Svstem Measurements are not taken redundantly on this system. J Suction and discharge pressure measurement on the single pump provides a means for evaluating pu=p performance and flow passage condition. Surge tank level measurement provides a means for evaluating leakage (in or out) and verifying available NPSH for the pump. A loop seal on the tank vent requires that the level transmitter (DP type) be referenced to the top of the tank. This is done with a " dry" reference line. In order to allow verification that the line is actually free cf accumulated condensation (or liquid frc= any source) a small tubing line is provided to a point outside the shield. This may be used to blow out the reference line with compressed gas or to drain it by gravity if appropriate. Twe small instru- =ent valves are provided (in series) to assure tight shut-off and control gas or drain flow. Finally, a cap is provided to keep dirt out and serve }7 E F F E CTIVE REVISED <3 9h_. DATE PAGE !R CF DATE W E ST WG HQUS $ FC D M NSO P A 1014

W NSD REV. l as a third seal-off point. High and low level alarms are provided. Total cooling flow is ceasured by an orifice and DP transmitter. The signal is linearised by a square root extractor before display. Flow may be used to evaluate pump and heat exchanger performance and to evaluate heat removal rate; high and low fire alarms are provided. Westinchouse Decav Heat Removal System Pump suction pressure (reactor outlet) is ceasured by four (4) transmitters. Two o,f, these have a low range output used to verify pump NPSH. An alarm is actuated on low pressure. The other two have a high range, output which covers the permissible operating pressure of the system. One of each is assigned to "A" and the other to "B" for separation. With the pumps secured, the static head of water in the reactor systems may be inferred. Pump suction temperature is =casured twice (A & 3) in the suction of each pu=p, by 100 chs platinum RTDS. This reading is the reactor outlet temperature { (on the flowing pump) or the ambient temperature (on the non-ficwing pump after a suitable cooling period). Pu=p discharge temperature is measured twice (A & B) in the common discharge line. This measurement is also the heat exchanger inlet te=perature. This is also a source of reactor outlet tc=perature. Heat exchanger outlet tecperature (measured as A &. B) allcws evaluation of heat exchanger perfor=ance. Flow (measured as A & B) may be used to evaluate heat removal rate, along with temperatures. Flew signal is lineariced by a square root extractor before being displayed. Heat exchanger outlet ptessure (A & B) is also the supply pressure to the reactor inlet lines. When compared to pump suction pressure and/or heat exchanger inlet pressure, it provides a =eans to evaluate the condition of flow paths through the reactor and heat exchanger. It also provides a means to evaluate the pump developed head. DERS pump seal cooler flow is a local measurement (square law scale) used for initial setting of the small cooling ficw to the Westinghouse Decay Heat Removal Pumps. Once the flows are set, this indicator may be shut off since it will not be accessible during normal operation. Radiation leakage into this system will be detected by flowing a small stream of the fluid through a shielded detector. The detector is located outside the shield wall and the existing ficw is returned to a low pressure point in the 2ain fluid loop. Due to the sensitivity desired, it is not practical to shield the detector against background " shine" within the skid building. A high alarm is provided. A flow reter, supplied with the detector, alicus initial setting of ficw to the detector. Inlet and outlet temperature measurements are provided for the decay heat service cooler. Thesc =ay be used to evaluate performance of both coolers. A high alarm is provided on the outlet temperature. ,, 3 h 9h b EFFECTIVE R EVISE D b DATE PAGE 19 0F DATE WE STrNGHCUSE F o RM N$o P A 1014

1 VJ NSD REV. Service water flow is measured by an orifice and DP trarsmitter. The signal is linearized by a square root entractor before display. A high alarm is provided so that unexpected high flows will be noticed and heat exchanger tube vibration avoided. There is no instrumentation on the pump motor. V. ELECTRICAL DESIGN A single line diagram depicting the electrical system is shown in Figure 5.1. In addition to showing the electrical systems, the diagrams also show the distribution of components among the Turbine Building, the skid, and the control trailer from which the systems are operated. The electrical power to the Westinghouse design systems is provided from the TMI Unit 2 Turbine Building per Drawing TMI-1017, DHR Single Line Diagram. 4160 volt power to DHR pump motor LA is supplied from Sus 2-3 and DER pump motor 1B is supplied from Bus 2-4. Both of these buses are backed-up by Standby Diesel Generator sets. Unit substation 2-44 located in the Turbine Building and backed-up by Standby Diesel Generator set will be the nor=al power supply to the single Westinghouse Decay Heat Closed Cooling Water System Pu=p Motor. The cable supply to this motor is routed as Trcin "B". Upon loss of off-site power, and if the associated D-G f ails to start, power can be supplied to the Closed Cooling Water System Pump Motor and its associated valves from the D-G set serving Bus 2-3 by closing the bus tie between unit substations 2-34 and 2-44 These unit substations also provide power to Power Panel PDP-1A and PDP-13, respectively, which in turn provide power to two 430 volt Motor Control Centers located in the control trailer. These MCC's are used to distribute Train "A" and Train "B" power to the associated MOV's and instruments. The MCC's are equipped with reversing motor starters for the functioning of the MOV's. These starters are controlled from the hand switches on the control panel in the control trailer. The instrument power supplies are fed frca the 208/120 volt distribution panel boards (one 120 volt feed to each control panel) located in the 430 volt Motor Control Centers. Tha MOV's and instruments for the Closed Cooling Water System are supplied frem the MCC as Train "A". A single control panel (Train 3) is provided for the control and indication of Closed Cooling Water System components. Instrument, control, and power cable is qualified to IEEE Std. 383 and typical LCCA environment. Control and power cables will be acceptable for direct burial. IEEE Std. 383 qualified terminations shall be provided for the Westinghouse Decay Heat Removal System Punp motors and the Closed Cooling Water System pump motor. On the skids, cable will be routed thr'ough conduit. The power cables from the skid to the interface point at the Turbine Building will be direct burial. Conduit will be used in the pipe trench for the supply to the MCV's at the Fuel Handling Building wall. Provisions will be made to seal the conduit at tie Fuel Building wall and at the skid building wall. EFFECTIVE REVISED DATE PAGE 20 DF DATE _. t p /\\J e msmc.iouse acau Nso u icu

3 NSD n E v. I Spacing of conponents in the control trailer will allow for future expansion. Interconnecting cable tray will be provided between the MCC's and the centrol panels (at the top of these cor.ponents) for the interconnecting centrol cables. Grounding provisions will be available for =otors, instrument racks, MCC's, and control panels. Also, bare copper M/0 ground wire shall be routed with each Sky and 480v power cable frc= the Turbine Building to the Skid Building and to the control trailer. i. f O e T e l EFFECTIVE REVISED DATE PAGE 21 0F DATE q 1 [3 ,, r t' J i wesTisc-ouse scav Nso u ic'd

4-l(r o 6 0 S 2-3 416 0 P._,O S 2 -4 1100A) )l'2.OOA "P 'n "T)" i ,) 'O 4 8 0 V f5 0 S 2e 3 4 480V BUS 7-44 ~ 'l' ,f, ) l)n.o. l) l) j~ [6g 1. l v a 3 PWR PNL PDP-I A PWR PNL PDP-16 DH A P-I A DHA-P-1B o 0 400 250 400 O j DHR PUMP CLOSE D COOLIMCi DHR PUMP WATER PUMP MCC 6 MCC A ) ) II 2 2.5 K'/ A 't.2. 5 K V A j tsi WY W3 % o ~8 [] 3 208/i2Ov 20s/izov ,o p O WeLilqh0U50 fleC!Ilc ColpolatlCQ II DECAY HE AT REMOV AL SYSTE ht ,,,u, h G l' I Gkfi_ l-!tiq_ D I 6 f3F( AM TR AIN IS pg o ---TRAIM /s d d 'dDEA" W ~f {j {_ g-~~ ~ ~ ~ ~ ~ ~ {~ p 7, ~- --~~ siifET-1 w, W F4UCLE AR E tet idGY SYSif MS PIT i t.Titi!4a il. P A.115 A %1

W NSD REV. VI. RADIATION SHIELDING DESIGN It is recommended that shielding be provided for the skid, pipe trench, and valve gallery to reduce radiation levels such that linited access to the external surfaces of the shielding may be permitted. Dose rates in these areas could be allow2d in the range of 5 to 50 millirem / hour and the area cou_d be posted with " Caution Radiation AREA" signs. It is reco== ended that shielding be designed based on a radioactivity con-centration of 1 X 10+3,2 0/' L in the fluid. This concentration of activity in the M Three Mile Island reactor priuary coolant was obtained by radiochemical analysis of three separate samples as discussed in appendix A. Scoping calculations were performed using point kernal methods outlined in Chapter 11 of Reactor Handbook, Volume 3, part B "Shieldic;," by E. P. Blizard. The calculations associated with this present analysis are believed conservative because: No credit was taken for attenuation by walls or piping. a. b. No credit was taken for decay of the solution source. Parametric results which provide equivalent thickness of concrete as a function of base rate are given below. Concrete Thickness (in.) Dose Rate (R/hr.) 0 108 2.6 49 5.3 22 10.6 4.3 18.5 0.28 26.4 0.019 33 0.0016 39.6 0.00013 EFFECTIVE R EVISE 0 ') \\ h DATE PAGE 23 0F

DATE, 9,i 6

v W E ST t NG r'OuSE F o A v NSo P A 1014

vd NSD R E V. As a result of this scoping analysis it is recommended that the side walls of the skid should be shielded with a minimum thickness equivalent to 2 1/2 ft. of concrete. Further, the roof of the skid should have a =inimum shielding equivalent to at leastl 2 feet of concrete. Controlled access above the roof sill be required. Accident Analysis The highest radiation level to be experienced by the alternate Dccay Heat Removal System will be from circulation of the primary coolant liquid. Specific activities for the nuclides in this fluid have been obtained by three independent analyses as described in appendix A to this section. The specific activity of Iodine I-01 in the primary fluid on April 11, 1979 had a mean value of 1.23X10jtC/at. 4 Far the purpose of estinating thyroid dose rates, 1*. is conservatively postulated tha the specific activity of I-131 is twice the mean value, or 4

2. 46 X 10 A4 C ML

, on April 11, in order to provide a scoping analysis. In agreement with the FSAR Amendment 48, Section 15.1.4 a leak rate is postulated of 2255 cc/hr. persisting for two hours, or a total leakage of 4.5 liters. If this water were to be collected in a pool or sump it is expected that only a factor of 1/10 of the iodine 131 would be released to the atmosphere. This would result in a site boundarv dose of 0.12 REM. If the average value of specific activity of 1.23 X 104 aC /nL was used the dose would be 0.06 REM. j Based on these results, it is recommended that the overall design should be such that gaseous and/or liquid radioactive leaks be contained and facilities should exist to allow prompt detection of leaks by the operator. 2) { E F F E CTIV E REVISED DATE PAGE24 0F DATE i A s sm.o,,ouse r o au sso ea s ou

• f NSD REV.

APPENDIX A METHCD OF DOSE CALCULATIONS L =A.X O.. B. D C F o-1 A Where A = total activity released in curies = atmospheric dilution factor 2 4(lC'+cecfn per Three Mile Island FSAR. This is a wort = case meteorology taken as the fifth percentile i.e. 95% of the time would be less than this. 3 B = Breathing Rate = 3.47 X 10(-4) M /cm. (" standard" =an breathing rate while not sleeping.) 6 DCF = Dose Conversion Factor = 1.48 X 10 for I-151, per NRC Reg. Guide 1.4 kr = Dose in rems to the thyroid (1) 0-1 ~ (1) No whole body doses where considered since they are less than thyroid doses. O,.

• )L' r

E F F E CTIVE REVISED L-l DATE PAGE 25 DF DATE WE 37'NGHoLSE F o RV NGO P A 1C14

W NSO n e v. APPE!! DIX 3 SUSOiARY OF F.ADIOCHCIICAL RESULTS* ANALYSIS OAK RIDGE S:U., BETTIS ALL CONCE'iTRATIONS ARE FOR APRIL 11, 1979 PROVIDED BY NUCLIDE CONCENTRA-CONC. CONC. MEAN HALF CO301-TION VALUE (STD DEV) LIFE ENTS 30 fML AC NL JLCfML MC-99 179 125 150 151 27 66 hrs. 4 I-131 8-2X103 4.55X103 2.4X104 1.23X10 1X104 8.05 Day (1) Cs-134 82 75.4 75 77 4 2 Yrs. (2) Cs-137 330 320 340 330 10 30 Yrs. (2) Cs-136 108 123 210 147 55 13 Daf (2) Ba-140 290 171 420 294 125 12-8 Day (2) La-140 160 135 270 188 72 40 hrs. (2) Sr-89 600 1337 657 864 410 50 Day Sr-90 50 149 73 91 52 29 Yrs. (1) The =ean value of I-131 decayed for an additional 28 day past April 11 is

f. l v id 'a C' /^ L

- use for dose cales. Double this value is 2 2'IC'AC/*L - use for dose cales. (2) The su= of the mean values tor Cs-134, Cs-137, Cs-136, Ea-140, and La-140 ts I.0"16 D CINL This value used for shielding analysis - with no further decay. (3) I-131 conc is good for April ll, ONLY. Any subsequent dose calculations should utilize appropriate decay. cn \\ G l* L-EFFECTIVE REVISED DATE PAGE 26 DF DATE W E '; T I N G nO US E 8 c A V '.5 0 P A 1014

N.V NSD a E v. VIII OUALITY ASSURA!!CE Westinghouse Quality Assurance Plan (FOAPP-TMI-1) was developed to describe the program under which Westinghouse conducts design, procurement and installation support for the Westinghouse designed decay heat removal systems. The plan addresses applicable functions of 10CFR50, Appendix 3 and the extent of compliance believed to be possible under the time constraints i= posed on the work. 1. Or2anization The Quality Assurance Manager is assigned the overall responsibility for the QA Program, and reports directly to the Project Manager. The QA Manager has the organizational authority to identify, initiate corrective action, verify con-formance of work, and to stop or control further processing of operations where conditions adverse to quality have been identified. 2. Quality Assurance Progian The QA program applies to safcty related =aterials, components and systems designed by Westinghouse. These itene are appropriately identified in design drawing, and bills of caterial. Where controlled conditions involving quality activities are identified they have been specified in codes, standards, process doccments, and inspection plans identified for the project. 3. Design Control Design drawings are prepared for systems, structures, and cceponents by cognizant design managers. Design control and verification is provided by the ongoing review of design managers, Engineering Manager and quality assurance. Final design review is the responsibility of the licensee. Design changes are processed and impleccnted in the same canner as the base document. 4. Procurement Doc" tent Contro? Purchase orders generated covering safety related procurements will be reviewed by Quality Assurance to assure that proper codes, and standards as defined in the design Bill of Material are referenced, and applicable documentation requirements specified. 5. Instructions, Procedure 4 and Drawings A general installa; ion procedure will be prepared and approved by Westinghouse and subsitted to the installer for his use. Welding and :!DE will be perfor=ed by the installer using existing site program controls. Westinghouse will review these procedures and qualifications to assure they are consistent with design and installation requirements. 6. Document Cor. trol All design drawings, installation procedures and Bills of Material will be approved by cognizant personnel prior to use. Control lists will be na 4tlined indicating approval status of these items. ) EFFECTIVE R EVISE D DATE PAGE 27 0F DATE WE ST NGHOUSE Fo AM N$O P A 1014

- $0( NSD REV. 7. Control of Purchaseu Material, Ecuincent and Services Materials, components and systems are received by and placed under the General Public Utility QA Program. Release for installation will be by the General Public Utilities QA Program. Source inspecting and release is as stated in the purchase order. 8. Identification and Control of Materials, Parts and Components Mechanical components are identified using appropriate identification =ethods to provide traceability to required drawings, records and documentation. Instrumentation will be identified and tagged as calibrated or acceptable. 9. Control of Scecial Process NDE performed by or for Westinghouse shall by conducted using peccedures approved by the Westinghouse Level III examiner on-site. NDE will be certified in accordance with applicable codes and standards. Welding processes and welders under the site control of Westinghouse shall be qualified in accordance with ASME requirements. Westinghouse QA will review and approve all welding qualifications and records. 10. Inspection activity shall be limited to those items scheduled for operational system assembly and installation. A detailed " Inspection Point Program" covering installation will be prepared for implamentation and use by the licensee. 11. Test Control Pre-cperational test procedures shall be prepared by Westinghouse for use by the licensee. Procedures will identify the necessary pre-operational test criteria. 12. Control of Measurement and Test rcuirment Inspection tools used by West. cuse for final acceptance shall be calibrated using standards traceable to '.;3S or other recognized sources. Applicabic instrumentation shall be identified and calibrated as received or prior to installation. 13. Handling, Shicodne & Storage These items are the responsibility of General Public Utilities and covered by their QA Program. 14. Inscection, Test & Ooerating Status All items identified for assembly and installation will be released after having been processed thru Ceneral Public Utilities receiving inspecticn. Westinghouse QA will monitor installation anc pre-operational testing, including leak on hydro testing. oqT E F F E CTIVE REVISED 3 b" DATE PAGE 20 0F DATE msTao-cuse acau Nso Pa tota

.. r V_/ NSD aEv-15. Non-conformine Materials Parts or comocnents Items which do not conform te requirements will be tagged and held for disposition. Rework or repair instructions shall be noted en the deviation notice. All repair or rework will be verified prior to use. 16. Corrective Action Conditions adverse to quality are promptly identified and dispositioned or corrected. Significant conditions adverse to quality are documented and reported to appropriate levels of 'a'estinghouse on-site canagement. 17. QA Records Records will be maintained for all activities af fecting quality, (except for these records delivered to GPU QA), and will typically include design criteria, installation procedures, caterial certifications, inspection and test records and nonconformance reports. t r ') ) Q r n EFFECTIVE l REVISED L DATE PAGE ao 0F l DATE araisosoVSE F o AV NSo P A 1CM .--}}