Fabrication, Quality Assurance & Performance of PHWR Fuel in India

Abstract

Pressurised Heavy Water Reactor (PHWR) is the backbone of the indigenous nuclear power programme in India. The Nuclear Fuel Complex (NFC) at Hyderabad is responsible for manufacturing zircaloy 4 clad natural uranium oxide fuel for the PHWRs in India, using magnesium-di-uranate concentrate from Uranium Corporation of India Limited (UCIL) and zircon sand from Indian Rare Earths Limited (IREL) as starting material. In the last two consecutive financial years (April-March), 1999-2000 and 2000-2001, the annual production of PHWR 220 fuel bundles at NFC exceeded 26,000 and the fuel for the initial cores of Kaiga 1 &2 and RAPS 3&4 were delivered. In September 2000, NFC crossed a major milestone with the manufacturing of the 200,000th fuel bundle. NFC received the ISO-9002 certificate for quality management system from Mis. TUV, India in December 2000. The uninterrupted and timely supply and high quality of fuel from NFC for the 12 operating 12 PHWR units paved the way for the Nuclear Power Corporation of India Limited (NPCIL) to achieve more than 80% average plant load factor (PLF) in 1999-2000 and 2000-2001, keeping the I-131 actvity in coolant channels way below the permissible limits. Several modifications in the fuel fabrication flowsheet, equipment and process parameters and quality control steps have led to significant reduction of radioactive aerosol, increase in productivity, minimisation of rejects and improvement in fuel quality.