After the completion of repair work to eliminate the leakage of sodium coolant in the air­ cooled heat exchangers (АНЕ) of loop "В" of the 2nd cooling circuit of the IВR-2 reactor, which took place in 2018, the FLNP Directorate has taken а decision to schedule the replacement of two operating АНЕs with new ones for 2022 because of their long service life (more than 40 years) and а high risk of repetition of sodium leakage in the АНЕ tube bundle assembly. Under the agreement with the specialized organization, at the end of April 2022, new АНЕs will be delivered to JINR.


In October 2021, another localized sodium leakage was detected in the АНЕ tube bundle assembly of loop "В", which did not result in the violation of established threshold limits and conditions of the safe operation of the reactor. In accordance with the current operating regulations, the IВR-2 reactor was temporarily shut down. The administration of IВR-2 and FLNP took а decision to prepare а Plan of Activities for the replacement of two АНЕs. Below are the main points of this plan.


Provisional dates and content of activities


Date of performance


The IВR-2 reactor shutdown

October 2021



Preparation and carrying out repairs of existing АНЕs (repairs are necessary to ensure the circulation of liquid sodium through the reactor core before the start of work on replacing the existing AHEs with new ones.)


April 2022


Replacement of the existing АНЕs with new ones

September 2022



Preparation of documentation on the replacement of АНЕs and а

package of documents for obtaining а license to operate the IВR-2 reactor. Submission of documents to Rostechnadzor.


October 2022



Expert examination of the set of documents for obtaining the Rostechnadzor license, consideration of the results of the examination, the decision of Rostechnadzor to issue а license for the

right to operate the IВR-2 reactor *


June 2023


Obtaining а license from Rostechnadzor for the right to operate the IВR-2 reactor*

July 2023


Resumption of operation of the IВR-2 reactor for physics experiments

September 2023


* - The dates are indicated taking into account the procedure established by the Administrative Regulations for the provision of state services by Rostechnadzor for licensing activities in the field of atomic energy use.