At Unit 2 of Novovoronezh NPP Phase II the cold and hot trials (CHT) of equipment have started.
The CHT stage will last for about 100 days. The trials have started from the “cold” phase which will take 35 days according to the schedule.
“We have already carried out pressure tests of the primary and secondary circuits for the pressure of 3.2 and 2.0 MPa and confirmed integrity of these circuits,” Plant Manager of Novovoronezh NPP Vladimir Povarov noted. “Now, we are to switch on reactor coolant pumps and carry out necessary integrity and strength tests. We must confirm that all mechanisms work routinely and later come to stages which relate to obtaining a Rostechnadzor’s license for loading nuclear fuel in the reactor,” he said.
The “cold” phase of CHT will be followed by the “hot” phase which will confirm performance of the essential and auxiliary equipment and systems of the reactor plant in the design and working modes. At this stage the start-up & adjustment and operation specialists will try four reactor coolant pumps at hot parameters (preset pressure of 16.0 MPa and coolant temperature of 280 Co) for 100 hours.
CHT is the important stage of start-up and adjustment. At this stage the performance testing of equipment is carried out. Trials of the overpressure protection system of the primary and secondary circuits are carried out, performance tests of reactor coolant pumps are conducted, and the reactor plant protection systems are tested.
This is the last large-scale technological operation at the power unit before the first criticality. The cold and hot trials are carried out to confirm safe and reliable operation of the power unit.