Atommash (part of the Atomenergomash machine engineering division of Rosatom) performed a test assembly of elements of a multi-purpose fast neutron research reactor (MBIR) in the Volgodonsk branch of AEM-technologies JSC. The reactor is being constructed in Dimitrovgrad at the production site of the Research Institute of Atomic Reactors of SSC RIAR JSC (part of the scientific division of Rosatom).

The scope of the test assembly includes 6 items of equipment with a total weight of 164 tons. The vessel with the support ring was installed using a crane into a 20 meters deep caisson on a specially designed support with a deviation of no more than 0.1 mm from the horizontal position of the main connector. A basket was installed inside the vessel to separate the coolant flows (liquid sodium) entering and leaving the MBIR and to organize the cooling of the reactor vessel and in-vessel internals. The MBIR basket weighs 45 tons, is about 6 meters long and 3.2 meters in diameter.

Three protective screens were installed further inside the equipment. They are designed to protect the research reactor’s vessel from the effects of heat flows of the hot coolant.

The assembly is 12 meters high, 4.1 meters in diameter, and the vessel’s weight is 83 tons. Specialists connected all the elements, checked their performance, assemblability, concentricity, and alignment. The further plans stipulate acceptance tests, conservation and packaging, and shipment of the MBIR equipment to the customer.

The MBIR is a thin-walled product: the thickness of the metal is from 25 to 50 mm with a diameter of 4 meters (for comparison, the VVER-1200 reactor has walls 300 mm thick). This creates additional risks of changed geometry of the equipment during handling. Specialized proprietary equipment was used to ensure strict compliance of the parameters throughout the entire production of the reactor.

The Multipurpose Fast Research Reactor (MBIR) will be the most powerful research reactor in operation or under construction in the world. Its main purpose is to conduct mass reactor tests of innovative materials and prototypes of core elements for nuclear power systems of the 4th generation, including fast neutron reactors with fuel cycle closure, as well as thermal reactors of small and medium power. The thermal power of the new reactor will be 150 MW.


Joint Stock Company AEM-Technologies, founded in 2007 as part of Atomenergomash JSC, the machine engineering division of the Rosatom State Corporation, is currently one of the leading Russian companies in the field of power engineering, a member of the Union of Mechanical Engineers of Russia. The company’s structure includes an engineering center staffed by experienced designers and process engineers, as well as two production sites: a branch of AEM-Technologies JSC Petrozavodskmash in Petrozavodsk and a branch of AEM-Technologies JSC Atommash in Volgodonsk.

A multi-purpose fast neutron research reactor (MBIR) is being constructed as part of the comprehensive program “Development of Engineering, Technologies and Scientific Research in the Field of the Use of Atomic Energy in the Russian Federation”. The reactor is being built in Dimitrovgrad (Ulyanovsk region) on the basis of SSC RIAR JSC (a company of Rosatom). The MBIR International Research Center (ICR) is being formed on the basis of the MBIR Rector. The scientific group will include Russian and foreign scientists and researchers. The activities of the center will be performed by a consortium—the “International Center for Research on the basis of the MBIR reactor”.

Atommash performs test assembly of the vessel with internals of the MBIR research reactor
Atommash performs test assembly of the vessel with internals of the MBIR research reactor