Fabrication of mercury target vessel

Wakui, Takashi  ; Kogawa, Hiroyuki  ; Haga, Katsuhiro  ; Futakawa, Masatoshi  ; Hayashi, Ryoichi*; Uchiyama, Naoyoshi*; Okamoto, Yoshinao*; Nakamura, Koji*

The construction of materials and life science experimental facility in J-PARC project had been completed. The mercury target vessel consists of triple-walled structure in order to prevent the leak of mercury to outside at the failure of the mercury vessel and to remove the heat of the safety hull, which covers the mercury vessel, due to the injection of the pulsed proton beams. The high fabrication accuracy is required for the mercury target vessel assembled by the welding. In this report, the required specification and basic structure of parts in the mercury target vessel are described and the fabrication procedure of the mercury target vessel by the vender is reported. In the fabrication of the mercury target vessel, there were many troubles such as large deformation due to the welding and then the vender repaired and brought the mercury target vessel to completion. Furthermore, improvements for the design and fabrication of the mercury target are reported.