Swiss Industries - 20 th June Divertor and Blanket Systems: Design, Required technologies and Schedule M. Merola Head of the Internal Components Division The views and opinions expressed herein do not necessarily reflect those of the ITER Organization.

Swiss Industries - 20 th June ITER Internal Components Divertor and Blanket directly face the thermonuclear plasma and cover an area of about m 2, respectively. All these removable components are mechanically attached to the Vacuum Vessel or Vessel Ports. Max heat released to the internal components during nominal pulsed operation: ~850 MW Removed by four independent water loops at 4 MPa water pressure, ~70 (inlet), ~120 (outlet) °C Blanket Divertor

Swiss Industries - 20 th June Overview of Material Mass MaterialApplicationMass (ton) Divertor components WArmor material53 CFCArmor material3 Cu and Cu alloyPipes, heat sink, functional material10 SteelStructural parts, pipes430 Ni Al bronzeKnuckle & Nose, pins21 Blanket components BeArmor material10 Cu and Cu alloyPipes, heat sink, functional material85 SteelStructural parts, pipes1400 Ni Al bronzePads, etc.tbc

Swiss Industries - 20 th June Divertor system main functions : Exhaust the major part of the plasma thermal power (including alpha power) Minimize the helium and impurities content in the plasma ITER Divertor

Swiss Industries - 20 th June Cassettes in a circular array held in position by two concentric radial rails. Divertor Cassette Layout

Swiss Industries - 20 th June Divertor System Scope - 54 Divertor assemblies Heat flux elements - 5 Major systems: Cassette Body + Integration Outer Vertical Target Inner Vertical Target Dome Plasma-Facing Comp Tests

Swiss Industries - 20 th June Power Handling HIGH HEAT FLUX COMPONENTS FOSSILE FIRED BOILER WALL (ABB) FISSION REACTOR (PWR) CORE ITER DIVERTOR DESIGN 12/15 mm ID/OD HEAT FLUX - average MW/m 2 - maximum MW/m – 5 10 – 20 Max heat load MJ/m 2 Lifetime years Nr. of full load cycles Neutron damage dpa Materials Ferritic-Martens. steel Zircaloy ~ CuCrZr & CFC/W Coolant - pressure MPa - temperature °C - velocity m/s - leak rate g/s Water-Steam <50 Water <50(SG) Water – – 11 <10 -7 Comparisons

Swiss Industries - 20 th June First Divertor (CFC/W) is well into procurement phase (5 PAs) −PFCs: Last PA signed March Definition of QA for all parties done. Preparation for prototype manufacturing. −HHF Testing facility in RFDA: PA signed March Commissioning planned July −Cassette Body and integration: PA signature 8 th May 2012 Status of Divertor HHF testing of Plasma Facing Units

Swiss Industries - 20 th June All 3 Domestic Agencies have been qualified. CFC Armoured Areas 1000 cycles at 10 MW/m cycles at 20 MW/m 2 W Armoured Areas 1000 cycles at 3 MW/m cycles at 5 MW/m 2 Divertor Qualification Prototypes

Swiss Industries - 20 th June Status of W Technology R&D in EU 2000 cycles at 15 MW/m 2 on W Most of all the W repaired monoblocks behaved like not-repaired ones 200°C, 0.1 and 0.5 dpa in tungsten - Successfully tested up to 18 MW/m 2 Unirradiated cycles x 20 MW/m 2 – no failure

Swiss Industries - 20 th June Blanket System Functions Main functions of ITER Blanket System: Exhaust the majority of the plasma power. Contribute in providing neutron shielding to superconducting coils. Provide limiting surfaces that define the plasma boundary during startup and shutdown.

Swiss Industries - 20 th June Modules 1-6 Modules 7-10 Modules ~1240 – 2000 mm ~850 – 1240 mm Shield Block (semi-permanent) FW Panel (separable) Blanket Module 50% 40% 10% Blanket System

Swiss Industries - 20 th June Design Heat load on blanket Group 1 : 1 – 2 MW/m² Normal heat flux panels Group 2 : 3.5 – 5 MW/m² Enhanced heat flux panels

Swiss Industries - 20 th June First Wall Finger Design SS Back Plate CuCrZr Alloy SS Pipes Be tiles Normal Heat Flux Finger: q’’ = ~ 1-2 MW/m 2 Steel Cooling Pipes HIP’ing Enhanced Heat Flux Finger: q’’ < ~ 5 MW/m 2 Hypervapotron Explosion bonding (SS/CuCrZr) + brazing (Be/CuCrZr)

Swiss Industries - 20 th June –Each DA must demonstrate technical capability prior to start procurement. –2 phase approach: I. Demonstration/validation joining of Be/CuCrZr and SS/CuCrZr joint (done) II. Semi-prototype production/validation of large scale components (on-going) FW Pre-Qualification Requirements 6 Fingers in 1 to 1 scale 2 slopes, 4 facets

Swiss Industries - 20 th June Shield Block Design Slits to reduce EM loads and minimize thermal expansion and bowing Poloidal coolant arrangement. Cut-outs at the back to accommodate many interfaces (Manifold, Attachment, In-Vessel Coils). Basic fabrication method from either a single or multiple-forged steel blocks and includes drilling of holes, welding of cover plates of water headers, and final machining of the interfaces.

Swiss Industries - 20 th June Blanket Manifold A multi-pipe configuration has been chosen, with each pipe feeding one or two BM’s replacing the previous baseline with a large single pipe feeding several BM’s -Higher reliability due to drastic reduction of number of welds and utilization of seamless pipes. -Higher mechanical flexibility of pipes. -Superior leak localization capability due to larger segregation of cooling circuits. -Well established manifold technologies.

Swiss Industries - 20 th June Tolerances General Tolerances described in Standards do NOT always meet our requirements ISO :1989 Tolerances for linear and angular dimensions … ISO :1989 Geometrical tolerances...

Swiss Industries - 20 th June Key Technology Areas Welded structures made of austenitic steels: NG-TIG, EB, Laser, TIG, MIG, … High heat flux joining technologies (Tungsten, Beryllium, CuCrZr): HIP’ing, brazing, casting, EB Heat Flux Testing of actively cooled components Non-destructive Examinations RX, UT, … Piping, flexible supports for pipes Insulating coatings, Low friction coatings, Anti-size coatings Precise machining, metrology High-Vacuum technologies, Pressure Tests, He Leak Tests

Swiss Industries - 20 th June Manufacturing / Welding Qualifications  Qualification of Welding Procedure Specification (WPS) WPS according to EN ISO and EN ISO nn Preliminary WPS is qualified according to EN ISO nn Qualification if quality level B achieved EN ISO 5817 for arc welding EN ISO serie for power Beam welding Welding Procedure Qualification Record (WPQR)  Other equivalent national or international standards and codes may be acceptable subject to the IO’s written approval.  The welding qualification for Quality Class 1 components shall be witnessed by ITER recognized Independent Inspection Authority, e.g. Third Party Inspector.  Welders, operators and NDT personnel shall be qualified (EN 287/ EN1418/ EN 473)

Swiss Industries - 20 th June NDT of welds in Steel Supports N.B. ITER Vacuum Handbook requirement: use of qualified liquid penetrants o Radiographic test for welds (EN 1435) o Ultrasonic Test for welds (EN 22825) o Visual Test for welds (EN 970) o Liquid Penetrant Test for welds (EN 571)  Volumetric examination  Other equivalent national or international standards and codes may be acceptable subject to the IO’s written approval. o Quality level B of EN ISO5817/ EN ISO o ITER Vacuum Handbook Attachment 1: Welding  Surface crack examination  Acceptance Criteria

Swiss Industries - 20 th June Engineering Support Services Design supporting analysis (Electro-Magnetic, thermal, mechanical) Development of component design, including the production of 2D drawings and 3D models. This activity requires the possibility to receive and deliver CAD files in of CATIA_V5 format. Good knowledge and understanding of the codes, standards, and design criteria used in ITER. The work may require the presence of the Contractor’s personnel at the working site of the ITER Organization, for extended periods of time, for the purpose of design review and data gathering.

Swiss Industries - 20 th June Divertor Procurement Schedule 17.P2C.RF Divertor Dome: signed 9 th June P2A.JA Divertor Outer Target: signed 17 th June P2D.RF Divertor Heat Flux Tests: signed 23 rd February P2B.EU Divertor Inner Target: signed 22 nd March P1.EU Divertor Cassette and Integration: signed 8 th May P2E.EU Divertor Rails: September 2014

Swiss Industries - 20 th June Blanket Procurement Schedule 16.P1A.CN/EU/RF Blanket First Wall: November P1B.CN/KO Blanket Shield Block: November P3.RF Blanket Module Connections: July P1A.EU Blanket Manifolds: March 2014

Swiss Industries - 20 th June The ITER plasma facing components are one of the most technically challenging components of the ITER machine An extensive R&D effort has been carried out world-wide to develop suitable high heat flux technologies o Divertor plasma-facing components o Blanket First Wall The ITER Divertor design and R&D has reached a stage of maturity to allow the start of procurement in June 2009 Substantial engineering effort (design and analysis) is planned for the Blanket System in 2012 Key technology areas includes: o Austenitic steel welding (Divertor cassette, Blanket shield block) o Piping (Blanket manifold) o Precise machining of metallic materials (Divertor rails) Summary and Conclusions