Maximum Initial Shut-In Casing Pressure (MISICP) or Maximum allowable shut in casing pressure is the initial shut-in casing pressure that will exceed formation strength at the casing shoe resulting in broken formation at the shoe.
How can we know and calculate the MISICP?
Leak Off Test (LOT) will tell you the maximum pressure which the shoe can withstand before breaking formation at the shoe. The LOT is the combination of surface pressure and hydrostatic pressure therefore you can apply this principle to calculate the MISICP.
The MISICP formula is listed below:
MISICP, psi = (LOT, ppg – Current Mud Weight, ppg) x 0.052 x TVD of shoe, ft
Please see the example demonstrating how to calculate the MISCIP by using the following information:
LOT = 15.0 ppg
Current mud weight = 10.0 ppg
Casing shoe depth = 4526’MD/4200’TVD
MISICP, psi = (15 – 10) x 0.052 x 4200
MISICP = 1,092 psi
Note: Please ensure that you use the TVD for calculating the MISICP.
Ref book: Formulas and Calculations for Drilling, Production and Workover, Second Edition
Well Control Books
if the casing pressure exceeds the MAASP while the influx is inside the casing, in this case could i shut in the well or carry on every is ok? please find for me the right answer. thank you.
You should carry on. Your casing shoe may or may not be broken because the mud sometimes strengthen the shoe.
You need to reduce kill rate in order to reduce overall pressure which will help you.
My partner and I stumbled over here coming from a different website and thought I might as well check
things out. I like what I see so now i’m following you. Look forward to finding out about your web page yet again.
Iam in Dire need of all drilling equipment and tools for various drilling operations: Example, Swamp. Shallow water, Deepwater, Offshore and Onshore environment,.