METHODS OF WELL CONTROL - BALANCE OF PRESSURES
BALANCE OF PRESSURES

FORMATION PRESSURE
Once the well is shut-in providing nothing has broken down, the pressures in the well will be in balance. What is lacking in hydrostatic head of fluid in the well is now being made up by surface applied pressure on the annulus and on the drill pipe.

Providing the bit is on bottom and the string is full with a known mud density this allows us to determine what the formation pressure is and hence what kill mud weight is required to achieve balance.
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