The operation is divided into two phases: "Hydraulic testing and circulation flushing of the primary circuit" and "Hot run".  The tests are conducted without nuclear fuel in the reactor and do not pose any nuclear threat.  Their task is to prepare the power unit for the first criticality, which is scheduled for the end of the year.

In order to ensure the power unit’s safe commissioning, a comparative analysis between designed and achieved performance criteria of the power unit equipment and systems is performed, along with the quality control of the works at all previous stages (design, manufacture, installation of equipment).

"Hydraulic testing and circulation flushing of the primary circuit"

At this stage, the equipment is tested without the use of thermal effects.

 All in all  89 systems of the reactor plant undergo the testing.

Experts check the conformity of primary circuit components to the strength and density design requirements.  Then operating reactor coolant pumps perform post-installation flushing of the primary circuit with chemically demineralized water, after installation of  the reactor internals and core simulator.  Various features of the reactor plant and primary circuit equipment are checked for conformity to their design values.

Reactor plant water chemistry is also adjusted, and Overall I&C (that is, Automated Process Control System) preliminary testing is completed.

"Hot run"

This stage involves functioning tests of the following reactor plant equipment:  auxiliary process systems of normal operation, and safety systems. Thereby, the primary circuit is filled with water and heated.  Main steam pipelines are blown down with their own steam, and primary and secondary circuits water-chemistry is adjusted.

The  "hot run" result shall prove functional capability of automatic control systems that provide instrumentation and control of reactor compartment normal operation  systems, security systems, ventilation systems and turbine compartment systems.

Note:

The Holding “Titan-2” is the largest in the North-West group of companies, erecting the most important objects of the nuclear industry and energy. The organization performs a full range of construction and installation works from engineering to commissioning.

The Holding “Titan-2” is one of the main contractors for the construction of power units No. 1 and No. 2 of the Leningradskaya NPP-2. Main organizations of the company perform 30% of general construction and 80% of installation works on the site. Specialists of the holding are engaged on the objects of the Leningradskaya NPP-2 first and second power units. The works are being performed in the buildings of the reactor, turbine, electricity, water, heating system and other structures of power units.