Directional drilling (or slant drilling) is the practice of drilling non-vertical . It can be broken down into four main groups: directional drilling, utility installation directional drilling, (horizontal directional drilling - HDD), and surface in seam (SIS), which horizontally intersects a vertical bore target to extract . Horizontal directional drilling bores underneath obstacles with a guided bit. The operator steers the bore head utilizing an angled pipe, pressurized fluids, and a steering tool that provides depth and positioning feedback.
[pdf] An integrated circulation temperature model for horizontal well drilling was developed, field-tested, and compared with results from vertical wells in order to accurately predict bottomhole temperature while.
[pdf] Wells are drilled directionally for several purposes: • Increasing the exposed section length through the reservoir by drilling through the reservoir at an angle.• Drilling into the reservoir where vertical access is difficult or not possible. For instance an oilfield under a town, under a lake, or underneath a difficult-to-drill formation.
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