There has been no damage to the about Rs 150 crore rig-Sagar Ratna-owned by the ONGC in the recent fire at one of the gas fields in Mumbai offshore.The Minister for Petroleum and Natural Gas, Mr K. Ramamurthy, told the Lok Sabha in a suo moto statement that the site of the fire, Platform B-121, 140 km west of Mumbai city, comprises a cluster of four free gas producing wells(named B,C,D and F).