A rotary drilling rig works by rotating a drill string, which applies downward pressure to a drill bit that grinds the earth. Drilling fluid or air is pumped down the drill string to cool the bit, carry cuttings to the surface, and stabilize the borehole.
[pdf] Exploration drilling projects in arctic and northern regions often take place in remote, cold, isolated and demanding locations such as lakes, muskeg areas and oceans. One of the major challenges for these projects is the lack of infrastructure making it unfeasible to employ barges or drilling vessels to support project. .
Ice pads can be grounded or floating depending on the water depth and the ice thickness required to support the intended loads. The design load should account. .
Ice pads can be constructed by free-flooding, with spray ice or with chipped ice. Typically, free-flooding is the most cost effective construction method however. .
The bearing capacity of the ice pad depends on the quality of the constructed ice. Proper construction procedures must be employed to ensure the highest ice.
[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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