Radius of Curvature Method is the most famous method for directional survey calculation. You can calculate North, East and TVD between directional surveys based on the Radius of Curvature Method as per formula below:
MD = measured depth between surveys in ft
I1 = inclination (angle) at upper survey in degrees
I2 = inclination (angle) at lower in degrees
Az1= Azimuth direction at upper survey
Az2 = Azimuth direction at lower survey
Calculation example for Radius of Curvature Method
Depth = 7500 ft
Inclination = 45 degree (I1)
Azimuth = 130degree (A1)
Depth = 7595 ft
Inclination = 52 degree (I2)
Azimuth = 139 degree (A2)
MD = 7595 – 7500 = 95 ft
As per the calculation above,
North = -49.97 ft
East = 50.66 ft
TVD = 62.91 ft
Please find the Excel sheet used for directional survey calculation with Radius of Curvature Method.
Ref book: Formulas and Calculations for Drilling, Production and Workover, Second Edition
You have a mistake in you TVD calculation equation for the radius of curvature method – you need to multiply nb 180/pi instead of (180/pi)^2
Thanks very much for checking me. It is my mistake when I typed in up. However, the calculation sheet in this post is correct. I already double check it. I correct my post as well.
good morning, sir.
I have some trouble with my survey calculation in directional drilling. (Im a student)
Why i give some data is negative in vertical section from surface until KOP? what does the negative vertical section mean?
Please read this post – What does the negative vertical section mean? – https://www.drillingformulas.com/negative-vertical-section-mean/
this is very valuable data , could you please give me this kind of data in pdf so that i may easily download it to increase my DD knowledge . i’m a student