Blowout Prevention System Flashcards
Describe what blowout is
Uncontrolled influx of formation fluid with sufficient pressure to damage rig equipment and injury to personnel.
Develops gradually as the hydrostatic pressure of the mud drops below the required value to contain the formation fluids.
When the formation fluids enter the well bore, the well is said to be, “kicking”. If the kick is not noticed and the well begins to flow at an uncontrollable rate then the well is, “blowing out”.
Describe what blowout preventers (BOP) are
Large valves at the top of the well which may be closed if the well starts to kick or blow out.
Operated remotely from a control unit for safety but can also be closed/opened manually.
Either sit in the substructure on the rig or on the sea floor.
Describe the operation and function of Annular BOPs.
Designed to shut around any size or shaped equipment that runs through the hole.
Closes around the drill pipe, drill collars and casing. It can also close an open hole.
Made of synthetic rubber with steel ribs in a doughnut shape that fill a steel body.
Compressed to fit around any size and shaped equipment.
Has a large advantage over other BOPs since it can seal the well in any circumstance.
Usually closed first when the well kicks.
Describe the operation and function of Ram-Type BOPs.
Pipe ram BOPs designed to close around a specific size of drill pipe, tubing or casing. Has two ram blocks with semi-circular openings and a two-piece rubber seal which centres the pipe and seals around it.
Blind ram BOPs similar to pipe ram except the packers don’t have any cut-out shape. They are used to seal the well when there is no drill string or casing inside.
Shear ram BOPs are a special type of blind ram BOP which cut through the drill pipe to seal the hole completely.
