Cold Tests of Yangjiang-4 Successfully Finished

At 2:20 pm on May 10, 2016, the pressure of primary circuit of Unit4 of Yangjiang NPP was reduced to atmospheric pressure with the pressurizer dump valve opened, which marked the successful completion of cold functional tests of the unit.

Cold test, an important milestone in NPP engineering construction, is the first comprehensive commissioning test after nuclear unit entering system commissioning phase, which is to carry out hydrostatic tests on reactor coolant system and partial nuclear auxiliary system pipelines and functional verifications for relevant equipment and systems.

At 2:17 pm on May 8, during the cold functional tests of the unit, the pressure successfully reached peak pressure level of 22.8MPa. And the inspections of primary circuit hydrostatic tests boundary were completed by specialized teams during pressure maintaining period. At 2:34 pm, the successful completion of hydrostatic tests was declared after the confirmation of inspection results.

The successful completion of cold tests marks that the main installation of the nuclear island of Unit 4 has been finished with high quality, thus the construction enters a new phase of commissioning and starting-up.