Page 103 - Formulas and Calculations for Petroleum Engineering

96 Formulas and calculations for petroleum engineering

2.49 Depth of a washout—Method 1

Input(s)
N s : Number of Strokes Required (unitless)
P o : Pump Output per Stroke (bbl/stroke)
C p : Drillpipe Capacity (bbl/ft)

Output(s)
D w : Depth of Washout (ft)

Formula(s)

P o
D ¼ N
w s
C p
Reference: Lapeyrouse, N. J., 2002, Formulas and Calculations for Drilling, Production and Workover, Second Edition
Gulf Professional, Publishing, Page: 70.

2.50 Depth of a washout—Method 2
Input(s)

N s : Number of Strokes Required (unitless)
P o : Pump Output per Stroke (bbl/stroke)
C p : Drillpipe Capacity (bbl/ft)
C a : Annular Capacity (bbl/ft)

Output(s)

D w : Depth of Washout (ft)

Formula(s)

P o
D ¼ N
w s
C +C
p a
Reference: Lapeyrouse, N. J., 2002, Formulas and Calculations for Drilling, Production and Workover, Second Edition
Gulf Professional, Publishing, Page: 70.

2.51 Derrick efficiency factor
Input(s)

E: Power Efficiency (per cent)
n: Number of Lines strung between crown block and travelling block (dimensionless)

Output(s)

E d : Derrick Efficiency Factor (per cent)