Jackup Rig

Jackup rigs stand on the ocean floor with their hull and drilling equipment elevated above the water on connected leg supports. Jackup rigs are generally preferred over other rig types in water depths of 400 feet or less, primarily because jackup rigs provide a more stable drilling platform with above water blowout prevention equipment. Premium jackup rigs are generally defined as rigs capable of drilling in water depths of 250’ and greater and are of independent leg design. All of our jackup rigs are considered premium jackups. All but one of our jackup rigs are equipped with cantilevers that allow the drilling equipment to extend outward from the hull over fixed platforms enabling drilling of both exploratory and development wells. The jackup rig hull supports the drilling equipment, jacking system, crew quarters, storage and loading facilities, helicopter landing pad and related equipment.

Dynamically-Positioned Semisubmersible Rig

Semisubmersible rigs are floating offshore drilling units with pontoons and columns that, when sea water is permitted to enter, cause the units to be partially submerged to a predetermined depth. Dynamically-positioned semisubmersible rigs are held in a fixed location over the ocean floor by computer-controlled propellers or "thrusters." ENSCO 7500, which is capable of drilling in water depths up to 8,000 feet, is a dynamically-positioned rig that also can be adapted for moored operations (anchored to the seafloor with mooring chains). ENSCO 8500 Series^® semis are enhanced versions of the ENSCO 7500 and capable of drilling in up to 8,500 feet of water. Enhancements over ENSCO 7500 include a two million pound quad derrick, offline pipe handling capability, increased drilling capacity, improved automatic station keeping ability and larger living quarters. With these features, the ENSCO 8500 Series^® rigs are especially well-suited for ultra-deepwater development drilling.

Barge Rig

Barge rigs are towed to the drilling location and are held in place by anchors while drilling activities are conducted. The Company’s barge rig has all of the crew quarters, storage facilities and related equipment mounted on the floating barge, with the drilling equipment cantilevered from the stern of the barge.