CNR ExploRA

Abstract in atti di convegno, 2020, ENG

Manufacturing, on-site installation and acceptance test activities of the MITICA vacuum vessel

Valente Matteo; Manfrin Stefano; Zaccaria Pierluigi; Barzon Andrea; Degli Agostini Fabio; Fasolo Daniele; Rossetto Federico; Tollin Marco; Bolcato Davide; Parma Antonio; Ruaro Diego; Zanotto Marco; Casa Mirco; Giupponi Mauro; Micò Montava Gonzalo; Moreno Juan Francisco; Rotti Chandramouli; Urbani Marc

Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Padova, Italy; CNR ISTP, Istituto per la Scienza e Tecnologia dei Plasmi, Sede di Padova, Italy; De Pretto Industrie, Italy; Fusion for Energy, Spain; ITER Organization, France.

The ITER Neutral Beam Test Facility, in an advanced construction in Padova, includes the installation, tests, and optimization of the full prototype of the ITER Heating Neutral Beams injectors (HNBs), named MITICA. The MITICA Neutral Beam Injector will host its main items in a SS304L vacuum vessel composed of two modules, connected between them on site: the Beam Source Vessel (cubic of 5 m side and 67 tons weight) containing the ion Beam Source and the Beam Line Vessel (section 4.5 m x 4.5 m, length 11 m and 76 tons weight) containing the Beam Line Components and the Cryopumps. The project requirements were transferred in the manufacturing design and in the fabrication process of these large vessels produced through welding and machining. The following steps were in particular carried out before and during manufacturing: o FE analyses to assess the structural integrity and limited deformations under vacuum loading conditions (leading to ribs reinforcement) o materials selection suitable for the specific application o qualification of special processes (welding and NDE) to ensure control of welding distortions and leak tight joints o implementation of double barrier sealings for the most critical connections o control of deformations under vacuum loads comparing displacement measurements with results of FE analyses. The Factory Acceptance Tests of the individual vessels are presented, including their Helium Leak Tests. The two vessels have been assembled on-site inside the MITICA bio-shield. They have been connected through a double sealing barrier composed of elastomer and a leak tight welded flange connection, previously qualified at the factory. The main outcomes of on-site final assembly and Site Acceptance Tests are described. Both vessels have been manufactured, installed and tested by De Pretto Industrie; the design and the technical support were provided by Consorzio RFX, while the procurement was managed by F4E.

31st Symposium on Fusion Technology (SOFT 2020), Virtual Conference, 20-25 September 2020