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European test blanket ancillary equipment unit development
Fusion Engineering and Design 86 (2011) 2121–2124
Contents lists available at ScienceDirect
Fusion Engineering and Design journal homepage: www.elsevier.com/locate/fusengdes
European test blanket ancillary equipment unit development T. Ilkei a,∗ , O. Bede a , S. Madeleine b , A. Aiello c , T. Baross a , B.-E. Ghidersa d , G. Grunda a , P. Hajek e , D. Keller b , L. Kosek e , B. Mészáros a , D. Nagy a , J. Németh a , F.S. Nitti c , Sz. Tulipán a , J. Wagrez b a
Association EURATOM-HAS, KFKI-RMKI, PO Box 49, 1525 Budapest, Hungary CEA-Cadarache, IRFM, 13108 St. Paul lez Durance, France ENEA FPN-FISING, C. R. Brasimone, 40032 Camugnano, Bologna, Italy d KIT, IRS, Postfach 3640, 76021 Karlsruhe, Germany e ˇ z plc, Husinec-Reˇ ˇ z 130, 250 68 Reˇ ˇ z, Czech Republic Nuclear Research Institute Reˇ b c
a r t i c l e
i n f o
Article history: Available online 20 January 2011 Keywords: ITER Test blanket module Ancillary equipment unit Integration Maintenance Design
a b s t r a c t This paper presents the recent results of the biggest removable component of the European ITER test blanket system (TBS), the ancillary equipment unit (AEU) development. The subsystem components are located inside the AEU, which ensures quick and reliable operation, maintenance and transport of these port cell components. The initiative concept of AEU frame structure was very similar to the preliminary design of the transfer cask but the self weight was already too high. Hence a significant structure optimization work, based on FEM analyses, has been implemented. The concept of support structure has been changed, and the weight appreciably has been decreased.In the next step the layout of subsystem components and routing of pipes have been developed taking into account the maintainability requirements of components and an additional function of AEU. It will be also the basic support of remote handling equipment, which will be deployed to the port interspace for pipes connection and disconnection operations. © 2011 Elsevier B.V. All rights reserved.
1. Introduction The main goal of test blanket module (TBM) experiment is to allow testing DEMO relevant tritium breeding and heat recovering capabilities in ITER reactor. Up to six concepts for various tritium breeding blanket systems will be tested simultaneously in 3 allocated equatorial ports (EP) of ITER (port nos. 2, 18 and 16). The following TBMs are planned to be installed in ITER. In EP #2: the Korean helium cooled solid breeder (HCSB) [1] and the Indian lead–lithium cooled ceramic breeder (LLCB) [2]. In EP #18: the Japanese water cooled solid breeder (WCSB) [3] and the US dual coolant lithium lead (DCLL) [4]. In EP #16 that is devoted to EU, two breeding blanket concepts are selected for the experiment. One is helium cooled pebble bed (HCPB) [5] originally developed by Karlsruhe Institute of Technology (KIT) in Germany and one is helium cooled lithium lead (HCLL) [6] originally developed by CEA in France. HCPB TBM is a ceramic breeder concept that contains lithium ceramic breeder and beryllium in the box as a breeder material and tritium extraction from the system is solved by low-pressure helium stream. HCLL TBM uses
∗ Corresponding author. Tel.: +36 1 392 2509. E-mail address: [email protected] (T. Ilkei). 0920-3796/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2010.12.058
slow-circulated liquid lithium–lead eutectic as a breeder material and tritium extraction is solved by ancillary system. The two EU TBMs will be installed in equatorial port #16 in a common port plug frame (PP) (Fig. 1). The PP contains the two TBM sets next to each other. Each set consists of the TBM box itself and a thick water cooled shield to provide additional neutron shielding behind the TBM boxes and pipes up to the backplane of PP. Port interspace (PI) locates the pipe forest (PF) that includes all the service pipe lines to create connection between the TBM box and its ancillary systems: helium cooling system (HCS), tritium extraction system (TES) and PbLi loop (PbLi) installed in port cell (PC). These ancillary equipments are integrated in a common support structure, called AEU. Configuration of AEU, as one assembly structure, facilitates installation/removal operation and allows the limitation of interfaces for TBM supply lines inside PC. Four interfaces have been defined to separate the TBS in the port and port cell. (IF1) – between TBM box and shield inside TBM set, (IF2a) – between TBM set and PF located inside PI, (IF2b) – between PF and AEU situated in PC after bioshield and (IF3) – between AEU and PC supply lines. This paper focuses on the design evolution of the biggest removable component of TBS, the AEU. The study shows the major steps taken during the design phases to arrive to the recent results, taking into account the maintainability of subsystems and structural considerations.
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Fig. 1. TBM system elements and interfaces.
2. Design requirements
Fig. 2. TCS like AEU design with pipe layout.
2.1. General
3.1. TCS like design
AEU shall be self-sustained and shall integrate all the ancillary equipments of the two TBSs, situated in the corresponding port cell. These ancillary equipments comprise, the piping up to the biological shield, liquid metal loops for the HCLL TBM option, part of coolant systems, part of the tritium extraction systems, part of instrumentation and diagnostic.
The preliminary support structure was built with standard “I” profile beams and rectangular tubes, based on the structure of TCS. AEU frame has been designed to be slimmer with 100 mm in order to ensure margins for outer covers and for any small parts which might be placed out of the frame. Among other alternatives, welded design of the frame structure has been selected; therefore a good weldable structural steel S235JR as material of frame structure has been chosen. As the side view in Fig. 2 shows, the side frame is stronger near to the plasma in order to support the significant weight of the shielded PbLi loop, which is the heaviest component of AEU (∼23 t). The big open triangle ensures the allocation of outgoing pipes on IF3. To install or remove AEU, 16 pipes at IF2b (HCLL: 3HCS, 2PbLi, 3Diagnostics – HCPB: 3HCS, 2TES, 3Diagnostics) and 10 pipes at IF3 (2HCS and 3TES for each system) have to be connected or disconnected (Fig. 2). The pipe parameters (diameter and wall thickness) have not been finalized at this stage of design, because of strong dependency on the results of thermal and stress analysis performed later. In the early design the pipe parameters of outgoing pipes from TBM cassettes were kept through the whole pipe system. Due to the high temperature (300–500 ◦ C) of operating pipes, thick thermal insulation will be necessary, but verification of its exact thickness will be subject of further studies. Its provisional thickness is 100 mm, therefore it has been decided to let at least 200 mm free space around each pipe. This distance is justified by the space requirement of maintenance tools (orbital welder, cutter, etc.) as well. Layout of IF2b has been designed in a half-circled shape in order to allow not only hands-on operation, but also robot access. The feasibility of pipe (dis)connection on IF2b (not only on IF2a as it is required) by RH matter, was also studied in this early concept. At IF3 the guiding principle was to locate pipes with the same 200 mm clearance near to each other, where RH system or workers can handle them easily. The subsystem integration study started with several different versions, and finally the layout, presented in Fig. 3, was achieved. The design of subsystems had been still under development at this phase of integration. Therefore past configuration of subsystems has been implemented for the preliminary layout development. Important design criteria were to install radiating and tritiated components as close as possible to each other and as near as possible to the plasma side of AEU close to biological shielding. Furthermore, weight of PbLi loop has played vital role to place it closest to the bioshield, due to enforced structure of building at this
2.2. Dimension AEU transport shall be executed by the air transport system (ATS) of the equatorial transfer cask system (TCS) through the same corridors and elevators as TCS itself, therefore outer dimensions of AEU shall not be bigger than those of the TCS. AEU common support structure shall include appropriate shielding to allow personnel access into port cell during maintenance operation. 2.3. Weight Weight of AEU together with all integrated components inside and weight of air transport cask cannot exceed the total weight of TCS of 100 t. 2.4. Maintenance Installation and removal operation in IF2a is foreseen to be performed by remote handling (RH), therefore adequate area must be reserved for robot, but as a back-up solution, human access is also ensured by the layout of PF. Pipe connections of IF2a have to be arranged in an appropriate way to be accessible by a robot arm. Moreover, during maintenance operations integrated subsystems inside AEU shall be accessed by personnels at least from one side. 3. AEU design evolution The initiative concept of AEU frame structure was very similar to the preliminary design of the transfer cask but the self weight was already too high. Therefore a significant structure optimization work, based on FEM analyses, has been implemented. Besides weight reduction of frame structure, subsystems and pipe layout optimization have been worked out as well. At first a “TCS like” concept and later an optimized, “modular” concept have been worked out.
T. Ilkei et al. / Fusion Engineering and Design 86 (2011) 2121–2124
Fig. 3. Layout of subsystems in TCS like AEU design.
area. PbLi loop is followed by the two TES and diagnostics together with the two HCS components. Width of maintenance corridor was set as 500 mm, which is enough for a person and for most of industrial robot arms. Under the corridor, place has been reserved for pipes and support structure of the robot mover mechanism. Near to the port cell door, inside AEU, reserved space can be used for robot installation and maintenance related equipments. AEU layout has been developed to be compatible with any port cell maintenance operation. Hence the maintenance areas have been arranged in such a way, that every component is reachable at least from one side. Robot accesses were ensured for IF2b and even for IF3. 3.2. Modular design Due to evaluation of the subsystems some important integration parameters have been changed. Pipe diameters were increased and stress analyses did not approve the complicated pipe routing
2123
geometries. The new requirements led to a reconsidered concept. Pipe routings had to be simplified, so the possibility of RH maintenance on IF2b and IF3 has been rejected, only on IF2a has been kept, as it was required. In spite of that AEU is a mobile component, for the most time of ITER operation AEU will be a permanent weight (∼50 t) inside the port cell, not like the TCS, which causes only temporary load on the floor. Therefore, further optimization of AEU frame structure had been required to achieve significant weight reduction, simultaneously keeping sufficient strength to hold subsystems and withstand loads applied during transport and handling operations. The optimizing procedure began with preliminary calculation which aimed to evidence the viability of a frame structure without side beams. This preliminary calculation confirmed this concept is feasible. Following, rough FEM models had been built in the first steps and these had been refined in subsequent phases. During optimization procedure each frame configuration had been validated by detailed solid models and finest hexa mesh. Various versions had been analyzed until the optimal light-weight configuration had been found. Fig. 4 shows the initial (a) and optimized (b) configuration with load and stress distribution along the structures. Non-uniform beam structure and ATS transport required the design of floor fixing/lifting mechanism of which among numerous alternatives an electrically driven screw spindle concept has been selected. Further analysis performed on optimized structure to validate its stress resistance during non-horizontal lifting scenario. Fig. 5 represents the improved AEU modular design that consists of weight and structure optimized platform and supplementary light support frame to hold HCS ancillary components during tokamak operation. Additional function of this light support structure is to facilitate top routed HCS pipes to be removed during maintenance operation without additional cutting to be performed. As a consequence of new modular design configuration of AEU, major rework on pipe routing and interface layout has been performed. In contrast with previous design, side of interface IF3 has
Fig. 4. FEM analysis results of AEU frame optimization procedure.
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T. Ilkei et al. / Fusion Engineering and Design 86 (2011) 2121–2124
Fig. 5. Modular design of AEU with pipe layout.
been changed to avoid pipes crossing of maintenance corridor and the length of pipes has been significantly reduced. At interface IF2b pipes have been separated into two groups according to their tritium supply functionality. One group consists of Diagnostics and HCS pipes other the PbLi and TES pipes. Pipes are arranged in vertical lines with same clearance of 200 mm due to insulation thickness and hands-on maintenance space requirements. Pipe arrangement at IF2b and IF3 allows covering all tritium related components with one common confinement boundary during connection and disconnection operation. PbLi pipe positions have been updated to implement the sustainable slope for the PbLi pipes through the whole equatorial port in order to ensure the gravitational drain of PbLi eutectic. Routing of pipes has been succeeded to concentrate on two sides of support frame, on the top and on the maintenance corridor side. The design of subsystems has been significantly changing during the implementation of AEU integration design task. Hence reserved space of ancillary equipments needed to be adapted to modified requirements. TES volume has been significantly increased compared to the past conceptual design that resulted in volume occupation of total reserved space of both systems. Solution has been worked out by vertically lifting HCS components to create additional space for TRS components whose design is subject of ongoing development. Improved integration and optimized layout of finalized tritium extraction and removal system will be subject of future development. Keeping all the benefit of earlier design, layout of subsystems has been adapted to the new requirements (Fig. 6). Tritiated and radiating components stay as close as possible to each other and the biological shielding. PbLi loop remains the first component inside AEU from plasma side of bioshield and situated above enforced structure of port cell. Ancillary equipment of tritium extraction systems follows the layout. As a result of light weight frame structure without strong vertical and diagonal beams, maintenance can be performed outside of AEU dimensions as well that permits at least two sides’ access of each component. As in port cell, outside of bioshield, no strict requirement of remote handling operation of pipe cutting/welding is foreseen (radiation level <10 Sv/h after 24 h of tokamak shut down), maintenance corridor and pipe interface layout have been optimized for hands-on operations and simplified pipe routings.
Fig. 6. Layout of subsystems in modular design of AEU.
Modular design of AEU enables the reuse of platform to install RH equipment after all the subsystems have been dismounted in hot cell facility or using extra identical platform for RH equipment, which will be deployed to the port interspace for pipes connection and disconnection operations at IF2a and will be able to remove and install the pipe forest. 4. Conclusion This paper presents the design evolution of AEU support structure, integration of subsystems and pipe layouts at interfaces together with the routing of pipes. Significant optimization work has been performed to arrive from TCS like design to a modular, light-weight configuration that has been adapted to the ongoing development of ancillary systems. Thanks to the modularity, the layout can be further optimized following ongoing development of subsystems and lighter crane loads can be achieved for assembly and refurbishment. The independent chassis development is a significant step toward the pipe forest installation and removal concept, as well. Further optimization of AEU configuration can be realized after detailed evaluation of maintenance needs of subsystems in hot cell facility during refurbishment operation. Acknowledgments This work was carried out within the framework of the Grant F4E-2008-GRT-09 under the contract between TBM Consortium of Associates and Fusion for Energy (F4E). The views and opinions expressed herein do not necessarily reflect those of the F4E. References [1] S. Cho, et al., Fusion Engineering and Design 83 (December) (2008) 1163–1168. [2] E. Rajendra Kumar, et al., Fusion Engineering and Design 83 (December) (2008) 1169–1172. [3] M. Akiba, et al., Fusion Engineering and Design 84 (June) (2009) 329–332. [4] A. Ying, et al., Fusion Engineering and Design 81 (February) (2006) 433–441. [5] L.V. Boccaccini, et al., Fusion Engineering and Design 61–62 (November) (2002) 339–344. [6] J.-F. Salavy, et al., Fusion Engineering and Design 83 (December (7–9)) (2008) 1157–1162.
Contents lists available at ScienceDirect
Fusion Engineering and Design journal homepage: www.elsevier.com/locate/fusengdes
European test blanket ancillary equipment unit development T. Ilkei a,∗ , O. Bede a , S. Madeleine b , A. Aiello c , T. Baross a , B.-E. Ghidersa d , G. Grunda a , P. Hajek e , D. Keller b , L. Kosek e , B. Mészáros a , D. Nagy a , J. Németh a , F.S. Nitti c , Sz. Tulipán a , J. Wagrez b a
Association EURATOM-HAS, KFKI-RMKI, PO Box 49, 1525 Budapest, Hungary CEA-Cadarache, IRFM, 13108 St. Paul lez Durance, France ENEA FPN-FISING, C. R. Brasimone, 40032 Camugnano, Bologna, Italy d KIT, IRS, Postfach 3640, 76021 Karlsruhe, Germany e ˇ z plc, Husinec-Reˇ ˇ z 130, 250 68 Reˇ ˇ z, Czech Republic Nuclear Research Institute Reˇ b c
a r t i c l e
i n f o
Article history: Available online 20 January 2011 Keywords: ITER Test blanket module Ancillary equipment unit Integration Maintenance Design
a b s t r a c t This paper presents the recent results of the biggest removable component of the European ITER test blanket system (TBS), the ancillary equipment unit (AEU) development. The subsystem components are located inside the AEU, which ensures quick and reliable operation, maintenance and transport of these port cell components. The initiative concept of AEU frame structure was very similar to the preliminary design of the transfer cask but the self weight was already too high. Hence a significant structure optimization work, based on FEM analyses, has been implemented. The concept of support structure has been changed, and the weight appreciably has been decreased.In the next step the layout of subsystem components and routing of pipes have been developed taking into account the maintainability requirements of components and an additional function of AEU. It will be also the basic support of remote handling equipment, which will be deployed to the port interspace for pipes connection and disconnection operations. © 2011 Elsevier B.V. All rights reserved.
1. Introduction The main goal of test blanket module (TBM) experiment is to allow testing DEMO relevant tritium breeding and heat recovering capabilities in ITER reactor. Up to six concepts for various tritium breeding blanket systems will be tested simultaneously in 3 allocated equatorial ports (EP) of ITER (port nos. 2, 18 and 16). The following TBMs are planned to be installed in ITER. In EP #2: the Korean helium cooled solid breeder (HCSB) [1] and the Indian lead–lithium cooled ceramic breeder (LLCB) [2]. In EP #18: the Japanese water cooled solid breeder (WCSB) [3] and the US dual coolant lithium lead (DCLL) [4]. In EP #16 that is devoted to EU, two breeding blanket concepts are selected for the experiment. One is helium cooled pebble bed (HCPB) [5] originally developed by Karlsruhe Institute of Technology (KIT) in Germany and one is helium cooled lithium lead (HCLL) [6] originally developed by CEA in France. HCPB TBM is a ceramic breeder concept that contains lithium ceramic breeder and beryllium in the box as a breeder material and tritium extraction from the system is solved by low-pressure helium stream. HCLL TBM uses
∗ Corresponding author. Tel.: +36 1 392 2509. E-mail address: [email protected] (T. Ilkei). 0920-3796/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.fusengdes.2010.12.058
slow-circulated liquid lithium–lead eutectic as a breeder material and tritium extraction is solved by ancillary system. The two EU TBMs will be installed in equatorial port #16 in a common port plug frame (PP) (Fig. 1). The PP contains the two TBM sets next to each other. Each set consists of the TBM box itself and a thick water cooled shield to provide additional neutron shielding behind the TBM boxes and pipes up to the backplane of PP. Port interspace (PI) locates the pipe forest (PF) that includes all the service pipe lines to create connection between the TBM box and its ancillary systems: helium cooling system (HCS), tritium extraction system (TES) and PbLi loop (PbLi) installed in port cell (PC). These ancillary equipments are integrated in a common support structure, called AEU. Configuration of AEU, as one assembly structure, facilitates installation/removal operation and allows the limitation of interfaces for TBM supply lines inside PC. Four interfaces have been defined to separate the TBS in the port and port cell. (IF1) – between TBM box and shield inside TBM set, (IF2a) – between TBM set and PF located inside PI, (IF2b) – between PF and AEU situated in PC after bioshield and (IF3) – between AEU and PC supply lines. This paper focuses on the design evolution of the biggest removable component of TBS, the AEU. The study shows the major steps taken during the design phases to arrive to the recent results, taking into account the maintainability of subsystems and structural considerations.
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T. Ilkei et al. / Fusion Engineering and Design 86 (2011) 2121–2124
Fig. 1. TBM system elements and interfaces.
2. Design requirements
Fig. 2. TCS like AEU design with pipe layout.
2.1. General
3.1. TCS like design
AEU shall be self-sustained and shall integrate all the ancillary equipments of the two TBSs, situated in the corresponding port cell. These ancillary equipments comprise, the piping up to the biological shield, liquid metal loops for the HCLL TBM option, part of coolant systems, part of the tritium extraction systems, part of instrumentation and diagnostic.
The preliminary support structure was built with standard “I” profile beams and rectangular tubes, based on the structure of TCS. AEU frame has been designed to be slimmer with 100 mm in order to ensure margins for outer covers and for any small parts which might be placed out of the frame. Among other alternatives, welded design of the frame structure has been selected; therefore a good weldable structural steel S235JR as material of frame structure has been chosen. As the side view in Fig. 2 shows, the side frame is stronger near to the plasma in order to support the significant weight of the shielded PbLi loop, which is the heaviest component of AEU (∼23 t). The big open triangle ensures the allocation of outgoing pipes on IF3. To install or remove AEU, 16 pipes at IF2b (HCLL: 3HCS, 2PbLi, 3Diagnostics – HCPB: 3HCS, 2TES, 3Diagnostics) and 10 pipes at IF3 (2HCS and 3TES for each system) have to be connected or disconnected (Fig. 2). The pipe parameters (diameter and wall thickness) have not been finalized at this stage of design, because of strong dependency on the results of thermal and stress analysis performed later. In the early design the pipe parameters of outgoing pipes from TBM cassettes were kept through the whole pipe system. Due to the high temperature (300–500 ◦ C) of operating pipes, thick thermal insulation will be necessary, but verification of its exact thickness will be subject of further studies. Its provisional thickness is 100 mm, therefore it has been decided to let at least 200 mm free space around each pipe. This distance is justified by the space requirement of maintenance tools (orbital welder, cutter, etc.) as well. Layout of IF2b has been designed in a half-circled shape in order to allow not only hands-on operation, but also robot access. The feasibility of pipe (dis)connection on IF2b (not only on IF2a as it is required) by RH matter, was also studied in this early concept. At IF3 the guiding principle was to locate pipes with the same 200 mm clearance near to each other, where RH system or workers can handle them easily. The subsystem integration study started with several different versions, and finally the layout, presented in Fig. 3, was achieved. The design of subsystems had been still under development at this phase of integration. Therefore past configuration of subsystems has been implemented for the preliminary layout development. Important design criteria were to install radiating and tritiated components as close as possible to each other and as near as possible to the plasma side of AEU close to biological shielding. Furthermore, weight of PbLi loop has played vital role to place it closest to the bioshield, due to enforced structure of building at this
2.2. Dimension AEU transport shall be executed by the air transport system (ATS) of the equatorial transfer cask system (TCS) through the same corridors and elevators as TCS itself, therefore outer dimensions of AEU shall not be bigger than those of the TCS. AEU common support structure shall include appropriate shielding to allow personnel access into port cell during maintenance operation. 2.3. Weight Weight of AEU together with all integrated components inside and weight of air transport cask cannot exceed the total weight of TCS of 100 t. 2.4. Maintenance Installation and removal operation in IF2a is foreseen to be performed by remote handling (RH), therefore adequate area must be reserved for robot, but as a back-up solution, human access is also ensured by the layout of PF. Pipe connections of IF2a have to be arranged in an appropriate way to be accessible by a robot arm. Moreover, during maintenance operations integrated subsystems inside AEU shall be accessed by personnels at least from one side. 3. AEU design evolution The initiative concept of AEU frame structure was very similar to the preliminary design of the transfer cask but the self weight was already too high. Therefore a significant structure optimization work, based on FEM analyses, has been implemented. Besides weight reduction of frame structure, subsystems and pipe layout optimization have been worked out as well. At first a “TCS like” concept and later an optimized, “modular” concept have been worked out.
T. Ilkei et al. / Fusion Engineering and Design 86 (2011) 2121–2124
Fig. 3. Layout of subsystems in TCS like AEU design.
area. PbLi loop is followed by the two TES and diagnostics together with the two HCS components. Width of maintenance corridor was set as 500 mm, which is enough for a person and for most of industrial robot arms. Under the corridor, place has been reserved for pipes and support structure of the robot mover mechanism. Near to the port cell door, inside AEU, reserved space can be used for robot installation and maintenance related equipments. AEU layout has been developed to be compatible with any port cell maintenance operation. Hence the maintenance areas have been arranged in such a way, that every component is reachable at least from one side. Robot accesses were ensured for IF2b and even for IF3. 3.2. Modular design Due to evaluation of the subsystems some important integration parameters have been changed. Pipe diameters were increased and stress analyses did not approve the complicated pipe routing
2123
geometries. The new requirements led to a reconsidered concept. Pipe routings had to be simplified, so the possibility of RH maintenance on IF2b and IF3 has been rejected, only on IF2a has been kept, as it was required. In spite of that AEU is a mobile component, for the most time of ITER operation AEU will be a permanent weight (∼50 t) inside the port cell, not like the TCS, which causes only temporary load on the floor. Therefore, further optimization of AEU frame structure had been required to achieve significant weight reduction, simultaneously keeping sufficient strength to hold subsystems and withstand loads applied during transport and handling operations. The optimizing procedure began with preliminary calculation which aimed to evidence the viability of a frame structure without side beams. This preliminary calculation confirmed this concept is feasible. Following, rough FEM models had been built in the first steps and these had been refined in subsequent phases. During optimization procedure each frame configuration had been validated by detailed solid models and finest hexa mesh. Various versions had been analyzed until the optimal light-weight configuration had been found. Fig. 4 shows the initial (a) and optimized (b) configuration with load and stress distribution along the structures. Non-uniform beam structure and ATS transport required the design of floor fixing/lifting mechanism of which among numerous alternatives an electrically driven screw spindle concept has been selected. Further analysis performed on optimized structure to validate its stress resistance during non-horizontal lifting scenario. Fig. 5 represents the improved AEU modular design that consists of weight and structure optimized platform and supplementary light support frame to hold HCS ancillary components during tokamak operation. Additional function of this light support structure is to facilitate top routed HCS pipes to be removed during maintenance operation without additional cutting to be performed. As a consequence of new modular design configuration of AEU, major rework on pipe routing and interface layout has been performed. In contrast with previous design, side of interface IF3 has
Fig. 4. FEM analysis results of AEU frame optimization procedure.
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T. Ilkei et al. / Fusion Engineering and Design 86 (2011) 2121–2124
Fig. 5. Modular design of AEU with pipe layout.
been changed to avoid pipes crossing of maintenance corridor and the length of pipes has been significantly reduced. At interface IF2b pipes have been separated into two groups according to their tritium supply functionality. One group consists of Diagnostics and HCS pipes other the PbLi and TES pipes. Pipes are arranged in vertical lines with same clearance of 200 mm due to insulation thickness and hands-on maintenance space requirements. Pipe arrangement at IF2b and IF3 allows covering all tritium related components with one common confinement boundary during connection and disconnection operation. PbLi pipe positions have been updated to implement the sustainable slope for the PbLi pipes through the whole equatorial port in order to ensure the gravitational drain of PbLi eutectic. Routing of pipes has been succeeded to concentrate on two sides of support frame, on the top and on the maintenance corridor side. The design of subsystems has been significantly changing during the implementation of AEU integration design task. Hence reserved space of ancillary equipments needed to be adapted to modified requirements. TES volume has been significantly increased compared to the past conceptual design that resulted in volume occupation of total reserved space of both systems. Solution has been worked out by vertically lifting HCS components to create additional space for TRS components whose design is subject of ongoing development. Improved integration and optimized layout of finalized tritium extraction and removal system will be subject of future development. Keeping all the benefit of earlier design, layout of subsystems has been adapted to the new requirements (Fig. 6). Tritiated and radiating components stay as close as possible to each other and the biological shielding. PbLi loop remains the first component inside AEU from plasma side of bioshield and situated above enforced structure of port cell. Ancillary equipment of tritium extraction systems follows the layout. As a result of light weight frame structure without strong vertical and diagonal beams, maintenance can be performed outside of AEU dimensions as well that permits at least two sides’ access of each component. As in port cell, outside of bioshield, no strict requirement of remote handling operation of pipe cutting/welding is foreseen (radiation level <10 Sv/h after 24 h of tokamak shut down), maintenance corridor and pipe interface layout have been optimized for hands-on operations and simplified pipe routings.
Fig. 6. Layout of subsystems in modular design of AEU.
Modular design of AEU enables the reuse of platform to install RH equipment after all the subsystems have been dismounted in hot cell facility or using extra identical platform for RH equipment, which will be deployed to the port interspace for pipes connection and disconnection operations at IF2a and will be able to remove and install the pipe forest. 4. Conclusion This paper presents the design evolution of AEU support structure, integration of subsystems and pipe layouts at interfaces together with the routing of pipes. Significant optimization work has been performed to arrive from TCS like design to a modular, light-weight configuration that has been adapted to the ongoing development of ancillary systems. Thanks to the modularity, the layout can be further optimized following ongoing development of subsystems and lighter crane loads can be achieved for assembly and refurbishment. The independent chassis development is a significant step toward the pipe forest installation and removal concept, as well. Further optimization of AEU configuration can be realized after detailed evaluation of maintenance needs of subsystems in hot cell facility during refurbishment operation. Acknowledgments This work was carried out within the framework of the Grant F4E-2008-GRT-09 under the contract between TBM Consortium of Associates and Fusion for Energy (F4E). The views and opinions expressed herein do not necessarily reflect those of the F4E. References [1] S. Cho, et al., Fusion Engineering and Design 83 (December) (2008) 1163–1168. [2] E. Rajendra Kumar, et al., Fusion Engineering and Design 83 (December) (2008) 1169–1172. [3] M. Akiba, et al., Fusion Engineering and Design 84 (June) (2009) 329–332. [4] A. Ying, et al., Fusion Engineering and Design 81 (February) (2006) 433–441. [5] L.V. Boccaccini, et al., Fusion Engineering and Design 61–62 (November) (2002) 339–344. [6] J.-F. Salavy, et al., Fusion Engineering and Design 83 (December (7–9)) (2008) 1157–1162.