Differential Sticking | Causes & Freeing Procedures
What Is The Definition Of Differential Pipe Sticking?

In general, differential sticking is a situation that may happen during any stage of drilling the well and cause the drill string or casing to stuck (no upward or downward movement). It actually happens when the hydrostatic pressure, ph (which acts on the outside wall of the Pipe) is more than the pore pressure, pf (which leads to force the pipe into the mud cake).
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