Located near Sakhalin Island off the Pacific coast of Russia, the Berkut Oil rig is the largest in the world. Weighing approximately 200,000 tons, this engineering marvel sits 35 meters below the seafloor and has an estimated maximum oil extraction capacity of 4.5 million tons annually.
[pdf] “Blue Whale 1,” the world’s largest and most advanced ultra-deep-water semi-submersible drilling rig was built by Yantai CIMC Raffles Offshore Limited in east China's Shandong Province. The 42000-ton oil platform has cost $700 mil. more
[pdf] Jackup rigs are so named because they are self-elevating with three, four, six and even eight movable legs that can be extended (“jacked”) above or below the hull. Jackups are towed or moved under self propulsion to the site with the hull lowered to the water level, and the legs extended above the hull. The hull is actually a water-tight barge that floats on the water's surface. When the rig reaches the work site, the crew jacks the legs downward through the water and int.
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