STX Offshore & Shipbuilding Co. said Monday it obtained an order worth 620 billion won (US$578.9 million) to build 12 crude oil tankers. Under the deal with Navig8 Product Tankers Inc., a Singaporean shipper, STX Offshore & Shipbuilding will deliver the tankers by the end of June 2016, the South Korean company said in an e-mailed statement.