Directional drilling is a vital technique in petroleum industry. It has mainly three different profiles.
The first configuration is “Build and Hold” where the well is drilled vertically until it reaches the “kick off point (KOP)”. Then, the angle is built up to reach the required inclination. In the tangential section, this inclination is maintained reaching the target zone. This technique is mainly used to reach a target zone with low depth and a huge horizontal displacement.
The second configuration is “Build Hold and Drop” which is similar to the first type, except in the tangential section, where the inclination angel is reduced until it reaches the target zone. This technique is used when the target zone has a huge depth with low horizontal displacement.
The third configuration is “Deep Kick-off and Build” which is usually used in specific cases like side tracking and to drill a salt dome.
To reach such profiles, number of different calculations should be done. Moreover these calculations have different techniques such as
1- Tangential method
2- Balanced tangential method
3- Average angel method
4- Radius curvature method
5- Minimum curvature method