Aban Offshore today said it will purchase a semi-submersible rig from Singapore-based Bulford Dolphin for about Rs 846.41 crore ($211 million).The company has entered into a memorandum of agreement with the Singaporean firm for purchasing the rig - Bulford Dolphin.The delivery of the rig is expected to take place in the fourth quarter of this fiscal, it said in a filing to the Bombay Stock Exchange.
