Drilling Formulas
Select units individually per field — ft/m, psi/kPa, ppg/SG & more
Hydrostatic Pressure
Pressure exerted by a column of drilling fluid.
Hydrostatic Pressure
5,200
Formation Pressure
Formation pressure from mud weight and depth.
Formation Pressure
7,800
Equivalent Mud Weight (EMW)
Convert pressure to equivalent mud weight.
Equivalent Mud Weight
12.5
Kill Mud Weight (KMW)
Required mud weight to balance formation pressure.
Kill Mud Weight
11
MAASP
Maximum Allowable Annular Surface Pressure.
MAASP
1,300
Overbalance Pressure
Pressure difference between wellbore and formation.
Overbalance
400
Circulating Bottom Hole Pressure
BHP while circulating = hydrostatic + annular pressure loss.
Circulating BHP
5,400
Equivalent Circulating Density (ECD)
Effective mud density while circulating due to friction.
ECD
10.4
Pore Pressure Gradient
Formation pore pressure expressed as equivalent mud weight.
Pore Pressure Gradient
11.5
Fracture Gradient
Formation fracture pressure expressed as equivalent mud weight.
Fracture Gradient
17.3