Definition - What does Annular Pressure mean?
Annular Pressure is the pressure exerted by the hydrocarbons in the annulus of a well or between two strings of casing inside a producing well. At times Annular pressure is also known as sustained casing pressure, i.e., the high pressure that remains sustained in the well casing or in the annuli until it is properly handled to avoid any workover functions in a well.
Petropedia explains Annular Pressure
Annular pressure can be built up any time during the lifetime of a producing well. Changes in the pressure and temperature, mechanical shocks, etc., generally happen because of various ongoing nearby drilling or pressure buildups which in turn result in the formation of Annular pressure. Such pressure needs to be handled in order to avoid any workover operations. Some of the Annular Pressure challenges faced by operators are as follows:
- There are no accessible bleed points, thus any fluid or gas trapped behind the casing is avoided.
- Whenever a casing is cemented, damage due to trapped annuli should be avoided.
- Whenever cumulative stresses are administered, zonal isolations need to be maintained.
- A flow path in the cement sheath can be formed because of formation fluids or gases which need to be prevented.