(EnergyAsia, May 19) — Hydro Marine Services (HMS), a subsidiary of J. Ray McDermott, S.A. said its recently modified Intermac 650 barge has completed the launch of the largest jacket ever constructed in China.   Intermac 650 was contracted to Offshore Oil Engineering Co. Ltd. (COOEC) enabling the installation of the 213m high, 25,200-ton jacket…