Page 168 - Formulas and Calculations for Petroleum Engineering

Drilling engineering formulas and calculations Chapter 2 161

2.206 Stripping/snubbing calculations—Constant BHP with a gas bubble rising

Input(s)
Dp: Incremental pressure steps that the casing pressure will be allowed to increase (psi)
2
Ca: Annular Capacity (in. )
G: Gradient of Mud (psi/ft)

Output(s)

V: V for constant BHP with a Gas Bubble Rising (bbl)

Formula(s)

Ca
V ¼ DpÞ
ð
G
Reference: Formulas and Calculations for Drilling, Production and Workover, Second Edition, Lapeyrouse, Page: 142.

2.207 Stroke per minute required for a given annular velocity

Input(s)
AV: Annular Velocity (ft/min)
AC: Annular Capacity (bbl/ft)
q o : Pump Output (bbl/stroke)

Output(s)

SPM: Strokes Per Minute Required (unitless)

Formula(s)

AV AC
SPM ¼
q
o
Reference: Lapeyrouse, N. J., 2002, Formulas and Calculations for Drilling, Production and Workover, Second Edition,
Gulf Professional Publishing, Page: 12.

2.208 Stuck pipe calculations—Method-1

Input(s)
OD: Outer dia of tubing (in.)
ID: Inner dia of tubing (in.)
S: Stretch (in.)
PF: Pull force in thousands of pounds (1000lb)

Output(s)
fpc: Free Point Constant (dimensionless)
h f : Feet of Free pipe (ft)