Owing to four faulty valves AERB has decided to delay Kudankulam nuclear power plant

India's nuclear regulator ordered replacement of four defective plug valves of the system that cools the reactor of Kudankulam nuclear power plant after the problem was detected during ongoing pre-commissioning tests.
The defect in the components of the four valves - there are thousands of such devices in a nuclear reactor - was found during pre-commissioning tests early this year, officials said.
"During testing of thousands of indian butterfly valves installed in the plant, the performances of four valves of a particular type were found deficient," R Bhattacharya, Secretary, Atomic Energy Regulatory Board (AERB) said in a statement here Friday evening.
Officials said that the butterfly valves were in the Emergency Core Cooling System (ECCS) that removes heat from a nuclear reactor under extreme components. On finding the defective valves, the Nuclear Power Corporation of India Limited (NPCIL) had procured replacements through its Russian collaborators.
"These valves are requiring larger efforts to get corrected," another official said but added that this was not an unprecedented development.
AERB Chairman S.S. Bajaj said the new components have been procured and were being assembled.
The programme 'requires formulation of detailed quality assurance plans specifying the sequence of activities and identifying the quality control points at which physical inspection/verifications are performed by the Quality Assurance Groups of contractors/manufacturers as well as independently by NPCIL'.
It added that the AERB had cleared for an 'initial fuel loading' at the plant as part of the commissioning activities and that "satisfactory demonstrations of functional capability are a prerequisite for considering the plant suitable for operating phase."