Breakover Point Between Stripping and Snubbing Calculator
Enter the declared drilling engineering inputs below to solve L_ds. Variable definitions, units, the default calculation, and the available source trail are included on this page.
What is available in this record
This record provides the functioning calculator, formula, declared variables and units, a reproducible default result, and the available citation metadata. A separately written engineering interpretation has not yet been published for this calculation.
Formula, variables, and default calculation
Reproducible default result
With the default values shown below, the calculation returns L_ds = 3,767.520362 ft. Defaults demonstrate the implementation; they are not recommended field values.
6.25
2400
83
276
0.8092
19.5
Input definitions
D_p
inPipe or Drill Collar Outside Diameter
P_wb
psiWellbore Pressure
W_dc
lb/ftDrill Collar Weight
L_dc
ftDrill Collar Length
BF
dimensionlessBuoyancy Factor
W_dp
lb/ftDrill Pipe Weight
Output definitions
L_ds
Drill String Length Required to Reach Breakover
F
Force Created by Wellbore Pressure
W
Buoyed Weight of Drill Collars
W_adp
Additional Weight Required from Drill Pipe
L_bp
Drill Pipe Length Required to Reach Breakover
Source and record status
Source metadata identifies the relationship implemented by the calculator. Check the cited edition, unit basis, and scope against the engineering case before operational use.
Lapeyrouse, N.J. Formulas and Calculations for Drilling, Production and Workover, 2nd Edition, Page 139.
Open source reference