Drilled shafts are high-capacity deep foundation systems, also known as drilled piers, caissons, bored piles, or cast-in-drilled-hole piles (CIDH). Drilled shafts for structural support can be installed by the dry (open hole), stabilizing polymer slurry, or steel-cased methods.
[pdf] Mobile offshore Drilling Units (MODU) This type of rig is commonly used in connection with oil and/or natural gas drilling. There are more jackup rigs in the worldwide offshore rig fleet than other type of mobile offshore drilling rig. Other types of offshore rigs include semi-submersibles (which float on pontoon-like structures) and drillships, which are ship-shaped vessels with rigs mounted in t. OverviewA jackup rig or a self-elevating unit is a type of mobile platform that consists of a buoyant fitted with a number of movable legs, capable of raising its hull over the surface of the sea. The buoyant hull enables tra. .
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.
[pdf] Many oil and gas companies use mat-supported jackup for exceptionally soft unconsolidated sea bed conditions as in tidal deltas. With this type of rig, they replaced the spud cans with a large mat, often covering a sea bed area more significant than the vessel’s hull.
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