Chapter 5 Project Design Guidelines for Directional Drilling Projects
PROJECT DESIGN
Directional Drilling generally involves working in the subsurface region. Due to heterogeneous nature of soil strata, geological surprises are not uncommon. Added to this, the presence of natural as well as man made subsurface barriers imposes greater challenge to the drilling activity. Lesser number of surprises at the time of project execution means a better and safer project and this calls for proper project design i.e. development of a working plan based on the identification and quantification of all the required inputs, evaluation of site soil strata and other related features, and subsequently selecting a system which caters all the expected demands from the drilling operation.
As has been discussed in earlier sections, the directional drilling process involves creating a pilot hole in the first stage. Soil prior to this is in its original state (Dense in most cases). Further the barriers, both natural as well as man made, need to be avoided (the drill path should not pass through any of such barriers). The drill head therefore has to steer through a defined path and the project design starts with the pilot pattern.
Once the pilot pattern
is identified a project specific drilling plan detailing the complete
layout meeting the site requirements (detail about entry and exit angles,
curvature and the roofing over the drill path) needs to be prepared.....................for
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