Offshore StructuresOffshore Drilling Equipment

The drill string is lowered through aconduit (riser). The drill string consists of a drillbit, drill collar and drill pipe. Drill pipe sectionsare added at the surface as the well deepens.The 三年级作文猜猜她是谁 drill passes through a system of safetyvalves called a Blowout Preventer (BOP) stackwhich contains the pressures in the well toprevent a blowout (escape of pressure into theannular casing between the casing and the drillpipe or into the hole).Drilling fluid (mud) is pumped into thedrill pipe from the surface and flows throughsmall holes in the drill bit. The mud collectsrock cuttings and flows up the annulus betweenthe drill pipe and the casing where the rock isstrained out and the mud is recirculated. Theweight of the mud exerts a pressure on the rockand keeps the well under control.

JackUp Drilling RigDesign primarily exploratorydrilling; similar to a bargewith movable legs, the rig istowed to the site and legsare jacked down, engagingthe seafloor and raising theplatform.Depth shallow… mAdvantages () mobile, () stablewhen 周记200 elevated, () low cost& efficientDisadvantages () depends on weather windows for placement, () restricted to shallow areas,() seafloor scour, () blowout can cause collapse of platform due to soil fluidization