Swab And Surge In Drilling Definition & Calculations
Surging or swabbing pressures in drilling describe pressure changes in the annulus resulting from pipe movement. The swabbing occurs when the drill pipe is pulled from the well, which will force mud flows down the annulus to fill the void left by the pipe. But the surging occurs when the drill pipe is lowered into the well, then the mud is forced out of the flow line.
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