Hindustan Petroleum Corporation Ltd (HPCL) will complete expansion of its Vizag oil refinery in Andhra Pradesh to 15 million tonne per annum by June, its Chairman Pushp Joshi said on Sunday. HPCL is expanding the 8.33 million tonne per annum (MTPA) refinery and building a new one at Barmer in Rajasthan to bridge the gap between the fuel it produces and sells.