An Emergency Disconnect Package (EDP) is a piece of equipment used in the drilling and work-over (servicing or modification) of deep sea oil & gas wells, by
Mobile Offshore Drilling Rigs (MODU's) and
Well Intervention Vessels (WIV's). The EDP is designed for use in an emergency, when the MODU or WIV needs to quickly disconnect, and move away from the oil/gas well that it is drilling or working-over. Examples of when this might be necessary include unexpected
extreme weather
Extreme weather or extreme climate events includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Often, extreme events are based on a locati ...
that exceeds the MODU/Vessel's capability to maintain its position.
Under normal operating conditions, the MODU/WIV (which is floating on the sea surface) is connected to the oil/gas well (which is drilled in the sea bed) by a vertical (or near-vertical) piece of steel pipe, called a
marine riser
Marine is an adjective meaning of or pertaining to the sea or ocean.
Marine or marines may refer to:
Ocean
* Maritime (disambiguation)
* Marine art
* Marine biology
* Marine debris
* Marine habitats
* Marine life
* Marine pollution
Military
* ...
. Tools and fluids are moved within the marine riser as required to/from the well. At the bottom of the marine riser, the EDP and other components that connect the riser to the well and allow the well to be shut-in when required, constitute a '
Lower Riser Package' (LRP).
When required to do so, the EDP disconnects from the LRP and isolates the riser from the environment. Thus the EDP allows the MODU/WIV to safely and quickly disconnect from the
subsea well and move away in an emergency. The EDP is designed to carry out its function while under load with a high disconnection angle.
An EDP consists of a connector to the rest of the LRP, an
isolation valve An isolation valve is a valve in a fluid handling system that stops the flow of process media to a given location, usually for maintenance or safety purposes. They can also be used to provide flow logic (selecting one flow path versus another), a ...
, an accumulator, a subsea control module and a connection point at the top for connection to the riser pipe. A production retainer valve shuts in the riser and the
annulus
Annulus (or anulus) or annular indicates a ring- or donut-shaped area or structure. It may refer to:
Human anatomy
* ''Anulus fibrosus disci intervertebralis'', spinal structure
* Annulus of Zinn, a.k.a. annular tendon or ''anulus tendineus co ...
master valve shuts in the riser. A crossover valve allows circulation of the riser after disconnection.
External links
Oil wells
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