Round Trip Ton Miles Formula
Round Trip Ton Miles calculates round trip ton miles for drillstring and rig mechanics workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (W_p, D, L_p, W_b, Wdc, Wdp, L, BF) are known and the assumptions behind the cited drillstring and rig mechanics relationship match the engineering case being checked.
Assumptions
- Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
- The declared units match the field-unit constants used in the formula.
- The cited formula applies to the selected petroleum engineering workflow.
Limitations
- The calculation does not replace a full engineering model or operating procedure.
- Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.
Common mistakes
- Mixing unit systems without converting the inputs.
- Using default example values as field recommendations.
- Applying the formula outside the source assumptions.
Default example
Using the default inputs, RT_TM equals 558.536932 ton miles.
16
10000
90
80000
147
19.5
500
0.85
Inputs
W_p
lb/ftBuoyed weight of drill pipe
D
ftDepth of hole
L_p
ftLength of one stand of drill pipe
W_b
lbWeight of traveling block
Wdc
lb/ftDrill collar weight in air
Wdp
lb/ftDrill pipe weight in air
L
ftDrill collar length
BF
dimensionlessBuoyancy factor
Outputs
RT_TM
Round trip ton miles
W_c
Buoyed drill collar weight minus buoyed drill pipe weight
W_p
Buoyed weight of drill pipe
L_p
Length of one stand of drill pipe
W_b
Weight of traveling block
L
Drill collar length
BF
Buoyancy factor
Wdc
Drill collar weight in air
Wdp
Drill pipe weight in air
Source and review
reviewedFormulas and Calculations for Drilling, Production and Workover, Lapeyrouse, N.J. (2002)
Lapeyrouse, N.J. 2002. Formulas and Calculations for Drilling, Production and Workover, 2nd Edition, Gulf Professional Publishing, Page 44.
Source