ML17138A537
| ML17138A537 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 01/15/1974 |
| From: | Becker, Knapp PENNSYLVANIA POWER & LIGHT CO. |
| To: | |
| Shared Package | |
| ML17138A531 | List: |
| References | |
| KWU-E3-2871, NUDOCS 7903150335 | |
| Download: ML17138A537 (82) | |
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KKB a I, CONSTRUCTION AND TASK OF THE RELIEF SYSTEH !=8rg C1 G E R MA N nslated from C gP, ~
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I HNICAL REPORT W/E 3 - 2871 CI cry III m ~a Kit K'Q ARY 1974 I Ihala'
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PROPRIETARY INFORMATION This document has been made NON-PROPRIETARY by the deletion of that'nformation which was classified as PROPRIETARY by KRAFTWERK UNION AG (KWU).
The PROPRIETARY information deletions are so noted throughout the report where indicated by, a) 'Use of the term KRAFTWERK UNION AG PROPRIETARY INFORMATION ~
b) Use of blocked out areas by cross hatch bands in the report text and figures/tables, e.g.
....". with a mass flow density ofh+~~Kg/m2s...";
%L% mm iii) should be kept below ~W ~~~ atm."
iv)
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Frankfurt 15 Januar 1974 P aceI t Date Technical Report KWU/E 3 - 2871 KRAFTHERE UNION File number R 521 R 113 Author R 521 R 113 Dr. Backer Countersignature apartment
Title:
Pages of Text: 20 Construction and task of Figures: 16 the relief system Circuit diagrams:
Key words (max. 12) to identify Diagr./oscillogr, the report's content: Tables:
Survey description of relief Reference list:
s stem Summary:
This report represents a description of the relief system in regard to its construction and its use during operation and accidents. It contains the operational boundary conditions and, in survey form, the requirements, on individual components.
By reference to detailed reports and specifications, the report helps the reader in the search for more detailed information.
The conclusion of the report is a discussion concerning the failure of individual components. It is impermxssible secondary damages can be ruled out.
shown clearly that (Kna ) (Dr. Becker) (Frenkel) (Zimmermann) II Author's signature Examiner Classifier Class For information Distribution lists (cover sheet only) lx KWU/GA 19 Erl lx /PSW 22 Ffm lx R 1Erl lx R 1 Ffm Transmission or duplication of this document, exploitation or communication of its content not permitted unless expressly authorised. Infringers liable to pay damages. All rights to the award of patents or registration of utility patents re-served.
8-1
NONLIABILITYCLAUSE This report is based on the current technical knowledge of KRAFTWERK UNION AG. However, KRAFTWERK UNION AG and all persons acting in its behalf make no guarantee. In particu-lar, they are not liable for the correctness, accuracy and completeness of the data contained in this report nor for the observance of third-party rights.
j This reservation does not apply insofar as the report is delivered in fulfillment of contractual obligations, nor with respect to licensing authorities or the experts appointed by them.
KRAFTWERK UNION AG reserves all rights to the technical in-formation contained in this report, particulary the right to apply for patents.
Further dissemination of this report and of the knowledge contained therein requires the written approval of KRAFTWERK UNION AG. Moreover, this report is communicated under the assumption that it will be handled confidentially.
8-2
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Distribution iist (internaI)
R-Ffm RZR 1 2 x RS RS 2 x RS RS 115/GKT RS 12/KKB RS 12/KKK RS 13/IHla RS 13/KKP 2 x RS 14/KKI RS 15 RS 2 RS 21 RS 213 R 11 - rfs R ll - Erl R '111 2 x R 113 X R 213 2 x R
R '3314 R 32 R 322 R 5 R 52 R 521 5 x 8-3
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TABLE OF CONTENTS Pacae 1..'ntroduction 8-5 2~ Description 'f the relief system 8-6
- 3. , Use of the relief system 8-10 3.1. Use for relief function 8-11 3~2~ Use for safety function 8-13 Operational boundary conditions 8-15
, 4.1. Blowdown capacity 8-15 4.2. Opening of the valves 8-17 4.3. Water level and submergence 8-17 4.4. Temperature distribution in the suppression 8-18 chamber during relief processes 4.5. Permissible pressure loads on the suppression 8-20 chamber 4.5.1. Pressure oscillations during vent clearing 8-21 4.5.2. Pressure oscillations during condensation 8-21
- 5. Requirements on individual components 8-22 5.1. Relief valves 8-22 5.2. Perforated-pipe quencher and blowdown pipe 8-22 5.3. Bottom mount 8-23 5.4. Restraining structure 8-24 5.5. Protective .tube 8-24
- 6. Discussion concerning the failure of individual 8-26 1
components Figures References
,8-4
I Introduction l
The purpose of the report,5.s to provide a comprehensive survey of the relief system. Important relationships in regard to the system's use are made clear and the require-ments on individual components are )ustified. The indi-cation of very specialized data and information was in-tentionally dispensed with for the sake of a better survey and, instead, reference is made to detailed reports and specifications. This facilitates the search for detailed information.
8-5
Descri tion of the relief s stem Two relief pipes branch off from the main-steam lines in the upper annulus of the drywell. They lead $ nto the suppression chamber, which is partially filled with water, and are sub-merged in the water pool (Figure 2.1). This system, called the relief system, is used to relieve the pressure in thet reactor pressure vessel in the event of accidents (e.g.,
failure of the main heat sink). For that purpose, main steam is blown into the water pool of the suppression chamber and is condensed as water. The total of 7 relief lines, which are equipped with quick-opening valves, are connected to,the main-steam lines inside the drywell. Figure 2.2 shows the relief system beginning at the valve. Zt consists of the relief valve, restraining structure, blowdown pipe, perforated-pipe quencher, bottom mount and protective tube.
Each of the 7 main valves is equipped with two separate pilot valves (Figure 2.3) which can be actuated either by interhal means (steam) or by external means (electromagnetically) .
Figure 2.4 shows a section through the spring>>loaded pilot-operated safety valve. After opening the control valves, steam flows from the reactor via the control line into,the pressure chamber of the main valves and the valve opens.
The valves are arranged in three groups which, are actuated at different reactor pressures (Section 3.1). 3 valves are 8-6
provided for the automatic depressurization mode (Section 3.1).
The arrangement
/
of the safety-relief valves is illustrated diagrammatically in Figure 2.5. From the Figure it is ob-P Il vious that the various groups of valves are, distributed uniformly over the circumference of the suppression chamber.
The 3 valves which are actuated for automatic depressuriza-tion are also distributed along the circumference. In this P way, adjacent valves are not actuated simultaneously (except in the safety mode (Section 3.2)) and the pool is heated uniformly when there is a high thermal load.
A fitting with an orifice plate is connected to the relief valve.
It is followed by a second fitting with two connec-tions for snifter valves, to which is connected the blowdown pipe with a nominal bore of 3 mm (Figure 2.2).
The orifice plate is meant to generate a steam velocity which is uniform in time and space by limiting the extent of the supersonic "braid" emerging from the valve.
The snifter valve opens at a low ad)ustable underpressure in the blowdown pipe with respect to the pressure in the drywell and allows air to flow in so as to equalize the pressure.
Large fluctuations of the water column in the blowdown pipe P
can thereby be avoided. More details of this process are described in /1/.
8-7
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The blowdown pipe widens in the suppression chamber to an inside diameter of L~ mm and is drawn in again to a nominal bore of i~Q mm at the water level. The submergence of the quencher is about %m with respect to the normal water level and centerline of the quencher arms. I 2.6 shows the construction of the perforated-pipe
'igure quencher which is rigidly connected "to the blowdown pipe.
The central member of the quencher between the blowdown pipe and the 4 quencher arms is a ball. The'angles between the arms are so chosen that favorable installation conditions are achieved in the suppression chamber (Figure 2-7). The ~
~ perforated-pipe quencher is built with a total of %++++'l L~~~ mm diameter..Two quencher arms, which point in the same circumferential direction, each have~+thrust bo'res in ,the arm bottom in order to produce a circulating flow in the suppression chamber so as to obtain a uniform temperature mixing of the pool water.
The~hole arrays themselves are arranged symmetr etricall'nd y thus in a neutral-force manner on the sides of the qu encher arms'o The installation conditions and arrangementt of the P erforated-P ipe quenchers in the suppression'hamber are shown in Figure The perforated-pipe quencher makes poss ssible a'alm'.7.
condensation up to high ppol temperatures +MW C) and re-
'uces the pressure oscillations which occur during clearing of the blowdown pipes.
S-8
- I KRAFTWERK UNION AG PROPRIETARY INFORMATION The restraining structure near the valve represents the anchor point of the relief system. A diagrammatic illustration is
'I shown in Figure 2.8.
The bottom mount is fastened to the sandwich structure by, webs. The connection between the perforated-pipe quencher and the bottom mount is so designed that a displacement of',
the perforated-pipe quencher in the vertical direction due to thermal expansion of the blojtdown pipe is pbssible (Figure' 2.9) ~
I '1 The task of the bottom mount is to guide the system and to absorb the transverse forces and moments about the vertical I
axis which act on the quencher.
8-9
Use of the relief s stem The description given here is taken essentially from /1/.
The safety/relief valves protect the pressure vessel in the event of pressure excursions. They prevent the reactor pres-sure from exceedingly%+times the pressure-vessel design pressure, even from maximum possible pressure transients.
ln the event of a loss of coolant and failure of the coolant injection system in the automatic depressurization mode, the valves also provide for a lowering of the reactor pressure in order to make possible the injection of water by the RHR system and the core spray system. The valves are also used briefly together with the turbine bypass systems in order to prevent a shutdown of the reactor in the event of a "Turbine tripout" or "Load rejection" accident.
The main valves have a dual function as combined safety and relief valves. The pilot valves open electromagnetically both in the safety function and in the relief function. The main valves are opened and kept open by internal means. Due to the higher response accuracy, the electrical control'sys-tem permits a more exact excitation of the valves and thus a closer staggering of the response pressures in the event of pressure excursions. The electrical~ controI system also makes it possible to open the valves and keep them open, as is necessary for automatic depressurization and when they are used together with the turbine bypass system. The pilot 8-10
S solenoid valves also receive a pneumatic supplementary load which is controlled via separate solenoid valves. This second external energy source, in combination with the elec-trical system, which is installed for the opening process, permits a very exact closing of the valves.
Use for relief function The main valves are opened by one of their two control valves in the following cases:
- Turbine tri out Because of the limited capacity of the turbine bypass system 3of the nominal steam flow rate), 1 valve opens for cai '%sec at a reactor power ofQ++Q full load and,l addi-tional valve opens for ca. i% sec at %% full load.
These two valves are designated by TSS in Figure 2.5 and are actuated directly from the Geamatic. The reactor pressure is thereby held at 70 bar.
- Hi h reactor ressure If the reactor pressure rises impermissibly due to failure of the control system or components, e.g., iq the event of a turbine tripout caused by failure of the main condenser, then the relief valves, staggered in three groups, open at the following set pressures:
8-11
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1st group L%%%%%%%%%%%
3rd group g~+++++~+~~~1 in order to handle this pressure transient. The time varia-tion of the reactor pressure is plotted in Figure 3.1 to-gether with an indication of the response marks for scram and safety/relief valves. The following boundary conditions are applicable:
<< failure of the main heat sink
- reactor at nominal load
- reactor shutdown due to high neutron flux and
- control-rod fast-insertion time of 5 sec.
A detailed description of the transient operational and acci-dent behavior is contained in /7/.
- Hold at ressure and tern erature when the main heat sink is not available Following the scram, the residual heat is removed by periodic opening of several valves in the first+~seconds and 1 valve thereafter.
- Emer enc shutdown when the main heat sink is not available The reactor is depressurised in kQhours by repeated manual opening of one valve according to a prescribed pressure vari-ation.
8-12
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- Automatic de ressurization in the event of loss of coolant
,In the event of a loss of coolant, one relief valve is opened automatically in any event in order to depressurize the system gradually. This occurs only if the liquid level in the reac-tor pressure vessel is high enough and, at the earliest k3 minutes after appearance of the accident criteria.
At a reactor pressure below+thar,+relief valves are opened in the event of a loss of coolant in order to create a closed emergency cooling loop: suppression chamber - pump - reactor-suppression chamber.
Finally, the depressurization system is used as a redundancy for the coolant injection system. Zf the coolant injection system does not convey a sufficient amount of water into the reactor when needed, then ~relief valves are opened in order to bring the low-pressure emergency cooling systems quickly
,into use by means of a rapid lowering of the pressure.
>> Performance test Each valve can be actuated individually by hand during opera-tion.
3 ' 'se for safety function In the improbable event that several valves should not open I
in their relief function during a reactor pressure transient, 8<<13
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the control valves open the main valves in the safety func-tion on the basis of a reactor pressure of ~+++ bar.
8-14
I 4 0 erational boundar conditions The relief system must satisfy the following boundary condi-tions in regard to the reactor pressure regulation and the effect on the pressure suppression system. This description represents an extension of the compilation of operational boundary conditions previously contained in /1/.
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- 4. 1. Blowdown capacity The nominal flow rate of one relief valve is +~ t/h at a reactor pressure of ~ bar.* This flow rate is utilized, in accordance with the relevant standards, as a basis for 'the calculation of reactor pressure transients which are covered by the safety function.
A value ofQ~3t/h at ~$ bar reactor pressure is expected for the actual flow rate by the valve manufacturer. The, flow rate actually expected by the valve manufacturer is shown in Figure 4.1 as a function of reactor pressure. The design, of the pressure relief system, especially the perforated-pipe quencher, is based on this flow-rate variation.
At high reactor pressures, a critical pressure ratio prevails above the seat of the safety/relief valve. The flow rate through the valve is then determined by the reactor pressure and is approximately proportional to it. If the reactor pres-sure drops to low values, then the pressure above the valve Trans ator s note: t ~ metric ton ~ 1000 kg 8-15
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seat finally drops below the critical pressure gradient and the flow rate decreases superproportionally with the reac'tor pressure. Since the blowdown capacity plays an important role at lowered reactor pressure for the automatic depressuri-sation mode described in Section 3, the flow rate per relief valve for low reactor pressures was plotted in Figure 4.2.
The upper curve corresponds to the flow rate through the valve as indicated by the valve manufacturer. In the plotted range of reactor pressure, these values also apply in prac-tice for the flow rate through the relief system with the, perforated-pipe quencher inserted further on.
The reduced flow rates illustrated in the lower curve occur for a pressure of~+ kg/cm~ (absolute) 'in the air space of the suppression chamber. The flow rate through the relief system at lowered reactor pressure is only slightly influ-enced by the perforated-pipe quencher (for reactor pressures Q~~ kg/cm~ (absolute)) but more strongly by a rise of the suppression-chamber pressure.
The variation of the liquid level inside the core shroud during the automatic depressurixation following a QW cm~
leak and failure of the coolant injection system is plotted in Figure 4.3. The illustration makes it clear that the liquid-level variation is favorably influenced at elevated pressure in the suppression chamber. This result is due to the fact that in the event of an elevated pressure in the 8-16
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suppression chamber, the low-pressure coolant injection sys-tem can already inject coolant at a higher reactor pressure and can convey more coolant at the same reactor pressure.
The reduced flow through the relief valve is thereby over-.
compensated. As the accident proceeds further, heat is also removed to an increasing extent via the injected cold water and an additional lowering of the pressure is effected.
4.2. Opening of the valves Zn order that the pressure in the reactor pressure vessel not rise impermissibly, e.g., in the event of failure of the main heat sink, the valve opening time of the safety/relief valves may not exceed Q~~~Rwith an additional dead time of Bk%
second. According to the measurements with KWW valve /8/,
the expectation value of the opening time is about ~~ ms.
However, shorter opening times down to g~> ms must not cause impermissible loads (in this regard, see Section 6). The valve opening time is defined as the total setting time of, I
the valve.
During the opening process, the flow rate increases in pro-portion to the time.
4.3. Water level and submergence The nominal water level is plotted in Figure 2.2. The sub-mergence of the quencher relative to the arm axis is 3.975 m for normal water level in the suppression chamber but the sys-tem must also remain operable for deviations of ~~+ and 8-17
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~~~~m in the water level; the latter, of course, in the event of sharply reduced reactor pressure (see Figure 4.4).
Detailed information is contained in /6/ concerning the con-densation of the steam when the quencher submergence is very small. When the depth of the water covering the quencher arms is only q~~~arm diameters (~i~~Qcm), a steam flow rate of~~t/h can still I be condensed completely. An appre-ciable lowering of the water level below the nominal value occurs if the suppression pool water is used for core flooding.
The lowest water level occurs in the event of a so-called runout of the suppression chamber. Zn the event of a suppres-
'sion chamber leak having the sire of a connection line, the relief system must still be capable of, permitting an auto-matic depressurization. Zn this case, at least the design pressure of the containment must not be exceeded. Figure 4.4, taken from /1/, shows the decrease of the flow rate with decreasing water level in the suppression chamber.
4.4. Temperature distribution in the suppression chamber during relief
~ processes P '%& && &W A most uniform possible temperature distribution of the water in the suppression chamber is necessary because then
- the heat capacity of the water is better exploited and
- thermal stresses at the walls and bottom due to nonuniform heating are avoided.
8-18
In order to achieve a uniform vertical temperature distribu-tion, the perforated-pipe quencher was installed very deep in the water space of the suppression chamber (Figure 2.2). The warm, specifically lighter water rises, mixes with the colder water situated above it and a uniform heating of the pool in the vertical direction is obtained. Due to a strong large-scale turbulence in the pool, which is generated by the flo~
processes and condensation processes at the quencher, a suf-ficient quantity of heat is also delivered to the water below the quencher /1/.
A uniform mixing in the circumferential direction is achieved by the thrust bores in the bottoms of two arms pointing in the same circumferential direction. The water is set into a slow motion by this one>>sided impulse on the water mass.
An important active element for the mixing of the pool water is the recirculation cooling system. After an averaged pool temperature of@~ C is exceeded, water is taken from the lowest point of the pool, cooled and carried back, distributed over the circumference of the suppression chamber, via four'HR legs near the water surface. In this manner, a recircu-lation of the suppression pool water is effected every half hour b'y the four RHR legs shown in Figure 2.5. This measure alone already produces a uniform temperature distribution, since the emergency shutdown of the reactor is extended over
%~hours, for example, i.e., over a Q>+times-longer time.,"
8-19
On the basis of the numerous investigations performed in /1/,
it can be assumed that the maximum deviation of the tempera-ture in the pool of the suppression chamber does not exceed L~~ C, except for regions in the immediate vicinity of the steam outlet. This difference should be maintained even if the pool is heated by /~AC by one or more blowdown lines during a blowdown process and, simultaneously, 2 out of 4 RHR system pumps are in operation.
The temperature range of the pool water in the vicinity of the quencher at which the blowdown can be effected with full flow rate should be at least between ~Q C and IW C. With a linearly decreasing flow rate, it must still be possible to pass through the temperature range from Q according to Figure 4.5. This stipulation was based on a mean pool temperature of up to~~C for full flow rate and a maximum permissible mean pool temperature of Q%C and the above-mentioned nonuniformity of the water heating.
4.5. Permissible pressure loads on the suppression chamber A distinction is made between two types of loads which gener-ate pressure loads on the suppression chamber during opera-tion of the blowdown lines. First, after opening the valve the water slug in the blowdown pipe is expelled, whereupon the air in the pipe is compressed. When this air is expelled, brief pressure oscillations are generated which act on the bottom and walls of the suppression chamber. This process is described in detail in /5/. The pressure loads to be 8-20
expected are also indicated there. Second, pressure oscil-lations which depend on the steam flow rate and the water temperature occur during the steady>>state condensation of steam. A detailed description of these processes and the expected pressure amplitudes is contained in /1/. Both loads are to be limited to the following limiting values in the plant:
4.5.1. Pressure oscillations during vent clearing For a reactor pressure of up to 88 bar and for the specified val've-opening times, the air oscillations on the bottom and wall should not exceed the value ezxzzxzwzwzr~
4.5.2. Piessure oscillations during condensation
.For the specified range of flow rate and temperature, the amplitudes on the bottom and wall should be kept 'ressure
~cia~/++~@ a~.
8-21
- 5. Re uirements on individual com onents The requirements which should ensure the operation and utili-sation of the individual components are compiled in this Section, taking into consideration the design details of the pressure suppression system. Xn addition, an extract from the specifications for the individual components is reproduced.
However, only the most significant loads are considered and reference is made to the individual specifications for the others.
5.1. Relief valves The safety/relief valves 'are used for pressure limitation in the event of accidents with a pressure rise in the reactor pressure vessel and for pressure relief in the event of loss-of-coolant accidents. The requirements with respect to re-sponse pressures, opening times and blowdown capacity and the data determinative for the design are indicated in /2/.
5.2. Perforated-pipe quencher and blowdown pipe The processes during vent clearing and the model extended for the perforated-pipe quencher to calculate the clearing pres-sure are described in detail in /5/.
.The pressure profile in the blowdown pipe during clearing due to pressure transients (Q++++++~~~i) is plotted versus time in Figure 5.1. For an extremely short valve-opening time of QL% ms, a maximum possible pressure of L+
8~22
results in the blowdown pipe, conservatively neglecting the rate of condensation of the inflowing steam at the pipe wall and at the water surface.
For an assumed g~3reduction of the outlet area of the quencher, the steady-state pressure in the nozzle is L% bar.
LW% response cases (produced primarily in the "Hold at pressure and temperature" accident) arise with respect to the valve actuated in the first valve group. A total of
+Lclearing processes result from this accident. All other response cases together, such as emergency shutdown, depressurization, etc., then amount to E%%
The other requirements relating to the load on the perforat-ed-pipe quencher and blowdown pipe are specified in /3/ for the operating conditions
- vent clearing
<< steady-state condensation and
- intermittent condensation.
5.3. Bottom mount The bottom mount of the quencher (Figure 2.9) is so con-structed that the flow around the quencher arm is not impaired.
The task of the bottom mount is to absorb the transverse forces and torsional moments acting on the quencher during the clearing process and steady-state condensation. The val-ues applicable in the individual load cases are specified in 8-23
5.4. Restraining structure The restraining structure (Figure 2.8) forms the anchor point of the relief system. It supports the outward-acting forces and moments especially during vent clearing, but also during condensation. The load on the restraining structure is speci-fied and described in detail in /9/.
5.5. Protective tube KRAFTWERK UNION AG PROPRIETARY INFORMATION 8"24
KRAFTWHRK UNION AG PROPRIETARY INFORMATION 8-25
Discussion concernin the failure of individual com onents A failure of the valve is conceivable in the following form:
- A valve gams and does not open. In this accident, the re-maining 6 valves can be used.
- A valve gams at first and then opens suddenly when full sys-tern pressure appears on the control pressure side. This perturbed opening behavior of the valve is taken care of by very small valve-opening times of onlyg~Qms, which are allowed for in the design of the system. Smaller opening times are not possible according to /8/. Furthermore, the GEM tests, in which a larger pressure is present on the con-trol pressure side than on the system side, demonstrate that the valve-opening time in the plant cannot be less than ~
A failure of the safety/relief valves to close can be caused by a failure of the pilot valves (which are present in dupli-cate) to respond. Accident sequences which could be produced in this manner are excluded by a limitation of the pool water temperature, which produces a timely shutdown of the reactor.
In order to prevent an impermissible amount of water from collecting at the valve seat and also in the control line, which delays the valve opening, the valve is drained and the control line is also provided with a specified drain hole.
On the other hand, these intentional leakage points, which 8-26
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also include the leakage via the piston rings, have such small dimensions that an impermissible amount of steam cannot flow out from the control side.
Should the redundant snifter valves not close completely, then a leak is produced in the drywell.
The quencher is so sized and made safe by production monitor-ing and inspection that a tearing<<off of the perforated-pipe quencher or one of its arms can be ruled out.
Zn the event of a leak in the blowdown pipe, the protective tube prevents an emergence of steam into the air space of the suppression chamber. Zn so doing, the load reduction achieved by the quencher is maintained, since the protective tube and the blowdown pipe form a small annular gap only LWmm wide in the water space of the suppression chamber.
Otherwise, the protective tube represents a redundance of the blowdown pipe. Therefore, the same loads due to internal'gres-sure and temperature have been specified for the protective tube as for the blowdown pipe.
The torsional moment exerted on the quencher is transferred to the bottom mount through guide bolts. The bolts have a re-dundant construction.
8-27
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KRAFTWERK UNION AG PROPRIETARY INFORMATION Figure... 4 c'0.
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'O RHR leg Q SRGUP DGGIGNATIDN DE AUTOMATIC DEPRESSURIZATION TSS TURBINE TRIPOUT VALVES 2.G5KKB.
F5r5uerree 2 Arrangement of the safety/relief valves 8-32
KRAFTWERK 'UNION AG PROPRIETARY INFORMATION 2.6 Figureo ~ ~ ~ ~ ~ ~
8-33
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$ 05 135'...
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p( 225'B00 325 ~ ~
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H6he' 200Ct 3 285 270 255'eight
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2
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Q- Gruppenbeeeichnung T.
~2 Group designation .
~PS use 2 Arrangement af the quenuhers in the 'suppression chamber,.EE>
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'8-'34
Ficture 2.8 Restraining structure of the KKB relief system 8-35
I Ball, '.Mmm'utside diamete
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+6 i fC,9 l5 I
'0-outside diam ter
+$ 3,S35 ~
KKB -
Piciure 2 9.
Bottom mount of the perforated-pipe quencher 6-36
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I KRAFTWERK UNION AG PROPRIETARY INFOKCATION Figure. 3. l 0 ~ ~ ~ ~ ~
8-37
E KRAFTWERK UNION AG PROPRIETARY INFOiU4ATION 8-38
Plow rate per relief valve Durchsat z je Entlast ungsventil 200 t/h 180 160 140 120 Flow rate according to 100 valve manuf acturer '
indication 80 60 40 Flow rate with a pressure ofQ~gkg/cm (absolute) in the suppression chamber 20 kg/cf"2 0 (abs. )
3 4 5 6 8 10 20 30 ate Fi ure 4.2 KKB Reaktordruck Reactor pressure KKB Abblaseleistung mit der Lochrohr-dQse bei abgesenktem ReoktordrucI<
Slowdown capacity with the perforated<<pipe quencher for lowered reactor pressure 8-39
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KRAFTWERK UNION AG PROPRIETARY INFOKIATION 4.3 Figure.....'..
8-40
KRAFTWERK UNION AG PROPRIETARY INFORMATION Fi ure 4. 4 and 4. 5 8-41
KRAFTWERK UNION AG PROPRIETARY INFO%CATION 8-42
I REFERENCES
/1/ Becker, Frenkel, Melchior, Slegers Construction and design of the relief system with perforated-pipe quencher KWU/E 3 2703, July 1973
/2/ Hofmann, Seemann Safety/relief valves Spec. no. 0/Y 83/SL 005
/3/ Knapp, Hoffmann, Koch, Frenkel Specification Design load for blowdown pipe and perforated-pipe quencher Spec. no.: KKB/XK/SD 001 Rev. 1, December 1973
/4/ Knapp, Hoffman, Koch, Frenkel Specification Design load for the bottom mount of the perforated-pipe quencher Spec. no.: KKB/XK/SD 002 Rev. 1, December 1973
/5/ Becker, Hoffmann, Knapp, Kraemer, Melchior, Meyer, Schnabel KKB - Vent clearing with the perforated-pipe quencher KWU/E 3 2796, October 1973 8-43
/6/ Hoffman, Becker Investigations of, condensation with the perforated-'ipe quencher when there is little water covering the, quencher arms KWU/E 3 - 2840, December 1973
/7/ Beckmann, Bockelmann, Brauhauser, Colmano Design reports concerning the transient operational and accident bepavior of the Brunsbuttel nuclear power plant K'lU/E 3 - 2752, August 1973
/8/ Hoffman, Sala, Becker, Frenkel, Schnabel, Weisshaupl, BrKuhauser, Gieseler KWW - Opening behavior of the pressure relief valves AEG/E 3 - 2336, August 1972
/9/ Becker, Koch Design load for the restraining structure of the relief system Spec. no.: KKB/XH/SD 010 Rev. 1, December 1973
/10/ Becker, Koch Design load for the protective tube of the relief system Spec. no.: KKB/XK/SD 003 8-44
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