Horizontal Directional Drilling Calculations For Oil & Gas
Planning & calculation of a horizontal wellbore is different from planning a normal directional drilling well for oil and gas. In a normal directional wellbore, the target is usually described in terms of a departure at a certain TVD. The target has tolerances in the horizontal plane (North and East). In a horizontal well, the target is most commonly described by the TVD plus or minus a tolerance. The departure target is usually more flexible than the TVD target.
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