Drilling EngineeringDirectional Drilling
Projected Turn Rate from Azimuth Change Formula
Projected Turn Rate from Azimuth Change calculates projected turn rate for directional drilling workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (A_1, A_2, I_1, I_2, dMD) are known and the assumptions behind the cited directional drilling 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, TR equals 8.550504 degree/100 ft.
A_1degree
20
A_2degree
45
I_1degree
15
I_2degree
25
dMDft
100
Inputs
A_1
degreeUpper Survey Azimuth
A_2
degreeLower Survey Azimuth
I_1
degreeUpper Survey Inclination
I_2
degreeLower Survey Inclination
dMD
ftMeasured Depth Interval
Outputs
TR
degree/100 ft
Projected Turn Rate
Source and review
reviewedDirectional drilling projected turn rate from azimuth change and average inclination.
Source