Well Control Formulas Part 2

These are some formulas used in well control operation. I will spit all content into several parts ^_^

Equivalent Circulating Density (ECD) , ppg

Equivalent Circulating Density (ECD) ,ppg = (annular pressure loss, psi) ÷ 0.052 ÷ true vertical depth (TVD), ft + (current mud weight, ppg)

Leak-off Test Equivalent Mud Weight (LOT), ppg

Leak off test (ppg) = (Leak off test pressure in psi) ÷ 0.052 ÷ (Casing Shoe TVD in ft) + (Mud Weight used for LOT in ppg)

Maximum Initial Shut-In Casing Pressure (MISICP), psi

This calculation is based on shoe fracture which is equal to Leak Off Test Pressure.

MISICP (psi) = [LOT (ppg) – Current Mud Weight (ppg)] x 0.052 x Shoe TVD (ft)

Kill Mud Weight to Balance Formation (KMW), ppg

KWM (ppg) = [Shut In Drill Pipe Pressure (SIDP), psi ÷ (0.052x True Vertical Depth (TVD) of the well, ft)] + Original Mud Weight (ppg)

Slow Circulation Rate (SCR), psi

SCR (psi) = Initial Circulating Pressure (psi) – Shut In Drill Pipe Pressure (psi)

Ref book: Formulas and Calculations for Drilling, Production and Workover, Second Edition
Well Control Books