Shanghai-based Huarun Dadong Dockyard has secured a contract for the Sparta retrofit project, which will convert a semisub rig into a 600-person floating accommodation rig, marking one of China’s more substantive rig-conversion projects in recent years. The yard signed the deal with Hong Kong-based China Merchants Harbour Engineering. The 2010-built 6th-generation deepwater drilling rig, built by Singapore’s …