Page 125 - Formulas and Calculations for Petroleum Engineering

118 Formulas and calculations for petroleum engineering

2.99 Hydromechanical specific energy

Input(s)
WOB: Weight on Bit (lbf)
2
A b : Area of Bit (ft )
N: Rotational Speedfor a Bit (ft/s)
Z: Factor for Energy Reduction (dimensionless)
P b : Presure Drop Across Bit (psi)
3
Q: Flow Rate (ft /s)
ROP: Rate of Penetration (s/ft)
T: Torque (lbf ft)

Output(s)
2
HMSE: Hydro Mechanical Specific Energy (lbf/ft )

Formula(s)

WOB 120 3:142 N T + 1154 Z P Q

b
HMSE ¼ +
A A ROP
b b
Reference: Samuel. E Robello. 501 Solved Problems and Calculations for Drilling Operations. Sigma Quadrant. 2015.
Houston, Texas, Page: 415.

2.100 Hydrostatic pulling

Input(s)
NS: Number of Stands Pulled (number)
Lavg: Average length per stand (ft)
PD: Pipe Displacement (bbl/ft)
mw: Mud Weight (ppg)
cc: Casing Capacity (bbl/ft)
pd: Pipe Disp. (bbl/ft)

Output(s)

BD: Barrel Displaced (bbl)
HP: Hydrostatic Pressure Decrease (Pulling Dry Pipe out of the Hole) (psi)

Formula(s)

BD ¼ NS Lavg PD
mw
HP ¼ BD 0:052
cc pd

Reference: Formulas and Calculations for Drilling, Production and Workover, Second Edition, Lapeyrouse, Page: 20.