What is bottom hole pressure in drilling?

Asked by: Shawn Mason

Bottom hole pressure is the pressure at the bottom of the hole, usually measured in pounds per square inch. In a flowing well the bottom hole pressure is equal to the pressure drop in the tubing plus the wellhead pressure. The reservoir or formation pressure at the bottom of the hole is known as bottom hole pressure.

Why is bottom hole pressure important?

Introduction. Estimation of well bottom-hole pressure at any existing operating conditions is continuously needed in oil and gas wells to monitor fluid movements inside the wellbore and the nearby wellbore regions. Petroleum wells normally produce a mixture of liquids and gases at the surface.

What is the hydrostatic pressure at the bottom hole?

The bottom hole pressure (BHP) is equal to the hydrostatic pressure (HP) on the annular side. If shut in on a kick, bottom hole pressure is equal to the hydrostatic pressure in the annulus plus the casing (wellhead or surface pressure) pressure.

How do you calculate bottom hole pressure?

Bottom Hole Pressure Relationship

1. Bottom Hole Pressure (BHP) = Surface Pressure (SP) + Hydrostatic Pressure (HP)
2. The first case: Hydrostatic column is water which is equal to formation pressure gradient so SP is equal to 0 psi.

What is BHP in drilling?

BHP is the bottomhole pressure in pounds per square inch. MW is the mud weight in pounds per gallon. depth is the true vertical depth in feet.

What happens to bottom hole pressure when fluid level drops?

It occurs when the fluids cannot drop below the string as fast as the pipe upward movement. This gap of fluid movement below the string generates a suction force leading to a bottom hole pressure decrease and allowing the formation fluids to flow into the well.

What is BHP pressure?

The pressure at the bottomhole. For non-flowing conditions, it is caused by the hydrostatic pressure of the wellbore fluid and by any backpressure held at the surface, if any.

What is reservoir pressure?

1. n. [Geology] The pressure of fluids within the pores of a reservoir, usually hydrostatic pressure, or the pressure exerted by a column of water from the formation’s depth to sea level.

What is the difference between hydrostatic pressure and formation pressure?

Formation pressure is the pressure acting on the fluids (i.e., formation water, oil, and gas) in the pore space of the formation. Normal formation pressures in any geological setting are equal to the Hydrostatic Head (hydrostatic pressure) of water extending from the surface to the subsurface formation.

What is wellbore pressure?

Wellbore pressure and fluid communication is the ability to detect pressure variations (increases or decreases) and fluid flows between wellbores during hydraulic fracturing. The ability to detect pressure pulses and fluid flow between oil and gas wells in conventional oil and gas producing formations is well known.

What is well head pressure?

Wellhead pressure – pressure at the top of the well, i.e., at its wellhead. It is measured by pressure gauges of the wellhead fittings. There are static and dynamic wellhead pressures.

What is formation pressure in drilling?

Formation pressure is the pressure of fluid contained in pore space of rock and there are 3 categories of the formation pressure which are normal pressure, abnormal pressure and subnormal pressure. 1. Normal Pressure: Normal pressure is the hydrostatic of water column from the surface to the subsurface formation.

What is normal pressure in drilling?

Normal pressures range between 0.43 and 0.50 psi/ft. Normal drilling muds weigh about 9 ppg (pounds per gallon) and exert a bottom hole pressure of approximately 0.47 psi/ft of depth.

What is abnormal pressure in drilling?

Abnormal formation pressure is a pressure above or below the normal hydrostatic pressure for a given depth. It cannot exist without a seal, for without a seal, the pressures would equalize to hydrostatic.