Drilling EngineeringWell Control
Initial Circulating Pressure Formula
Initial circulating pressure estimates the pump pressure required at the start of a well-control circulation using slow circulating pressure and shut-in drillpipe pressure.
How engineers use this formula
Use it in kill-sheet preparation when starting a constant bottomhole pressure circulation after a kick.
Assumptions
- Slow circulating pressure is measured at the planned kill rate.
- Shut-in drillpipe pressure is reliable and stabilized.
- The method follows conventional well-control pressure scheduling.
Limitations
- Does not replace a complete well-control procedure.
- Does not handle subsea choke-line friction, gas migration, or changing hydraulics by itself.
Common mistakes
- Using normal circulating pressure instead of slow circulating pressure.
- Using unstable shut-in pressure readings.
- Treating ICP as the final kill pressure.
Default example
Using the default inputs, ICP equals 1,700 psi.
SCRPpsi
900
SIDPPpsi
800
Inputs
SCRP
psiSlow Circulating Rate Pressure
SIDPP
psiShut-In Drill Pipe Pressure
Outputs
ICP
psi
Initial Circulating Pressure
SCRP
psi
Slow Circulating Rate Pressure
SIDPP
psi
Shut-In Drill Pipe Pressure
Source and review
reviewedDrilling Manual. Well Control Formulas & Illustrated Examples.
Source