PowerPoint Presentation

FishSomething breaks in or fall down the well during drillingFising tool is used to retrieve the fish

SpearD < D pipe

OvershootD > D pipe

Washover Pipe

Tapered Mill Reamer

Junk MillWireline Spear

Pipe StickingDifferential Sticking

Mechanical StickingCaused by :- Drilled CuttingsCaused by :- Formation Pressure > Hydrostatic Pressure

- Borehole instability- Keyseating

Mechanical Sticking

Sloughing ShaleSoft shale adsorbs water from the drilling mud expands out falls to the bottom of the well

Loss of CirculationLost circulation : uncontrolled flow of whole mud into formation thief zone

Formation DamageThe permeability of the reservoir rock is reduced as a result of foreign-fluid invasion

Corrosive GassesCorrosive gasses : CO2, H2S hydrogen sulfide embrittlement

Abnormal High PressureFluid pressure in formation > hydrostatic pressure cause blowout or kick