Under shut-in conditions, how is bottom hole pressure calculated?

Under shut-in conditions, the calculation of bottom hole pressure (BHP) is crucial for understanding reservoir behavior and well integrity. The correct method involves considering multiple components that affect the pressure at the bottom of the well.

The key to understanding this calculation lies in recognizing that BHP is influenced by hydrostatic pressure, which arises from the column of fluid in the wellbore. In addition to hydrostatic pressure, it is essential to factor in the Two shut-in pressures: the Shut-In Drill Pipe Pressure (SIDPP) and the Shut-In Casing Pressure (SICP).

Hydrostatic pressure accounts for the weight of the fluid column, measured in terms of pressure at the given depth. The SIDPP represents the pressure in the drill pipe when the well is shut in, while SICP indicates the pressure in the casing. Both of these pressures add to the total pressure experiencing at the bottom of the well.

Thus, the formula for calculating BHP combines hydrostatic pressure with both the SIDPP and the SICP. This comprehensive approach ensures an accurate reflection of the pressures at the bottom of the hole during a shut-in scenario. Using only hydrostatic pressure or any fewer components would provide an incomplete and potentially misleading assessment of the actual conditions within the