We have learned 2 cases about shoe pressure when kick is underneath shoe, and kick is passing the shoe,
When gas kick is being move above the shoe, do you know how much pressure at shoe has?
I will explain this case via this blog post.
First of all, let’s apply the hydrostatic pressure concept,
Bottom Hole Pressure = Pressure at casing shoe + Hydrostatic Pressure in the open hole underneath the shoe
The concept while circulating kick is the same. It means that you must keep bottom hole pressure constant. Therefore, you can write the equation like this:
BHP (constant while circulating) = Hydrostatic Pressure at Shoe + Hydrostatic Pressure in open hole
While kick above the shoe, the hydrostatic pressure in the open hole will remain constant therefore the pressure at casing shoe will remain constant.
Conclusion: Shoe pressure will remain constant after the bubble above the casing shoe.
Ps – assumptions : water base mud is used and kick is gas.
Reference book: Well Control Books