History of Directional Drilling
The oil and gas industry developed directional drilling in the 1920’s, and while the concept has remained the same, the technology has improved greatly over the years. In directional drilling, multiple wells can be drilled at multiple angles from one single well bore, expanding the area over which oil and gas can be gathered while simultaneously diminishing the overall environmental impact of the well. The oil and gas industry have developed a number of technologies to improve overall efficiency, such as using advanced drill sensors and global positioning technology to ensure the success of a well. Such technology has ensured well success by precisely controlling the direction the well is dug and directing it directly towards the sought after oil and gas reserves. In addition to these technologies, other tools such as whip stocks, bottom-hole assembly configurations, 3-D measuring devices, as well as specialized drill bits and motors have enabled a single location to service multiple wells dug at nearly any angle, thus tapping reserves more than a mile deep and miles wide.
Directional Drilling Process
While directional drilling can be achieved by simply pointing the drill in the direction desired, creating wells dug at multiple straight angles, more complex directional well arrays utilize a down-hole steerable mud motor and a bend near the drill bit. In this way, complex well angles can be achieved because the bend near the drill bit directs the bit in a different direction from the wellbore axis, while drilling fluid is simultaneously pumped through the mud motor in order to ensure that the entire drill string does not rotate. Once the desired angle is achieved, the entire drill string, including the bend, is rotated, allowing the drill bit to drill along the direction of the wellbore axis. This same technique can be utilized to achieve horizontal drilling, which includes any wellbore that exceeds 80 degrees and can even include a wellbore exceeding a 90 degree angle, or drilling upward. In drilling in this way, a well can be drilled across an oil and gas formation increasing production by as much as 20 times. Moreover, these techniques are being improved and tested in more difficult drilling environments, such as in hard granite formations as well as in deep wells whose internal temperature can exceed 600 degrees Fahrenheit. With the addition of high-temperature resistant drilling motors and modified drill bits which can drill into nearly any surface, directional drilling is now possible in nearly any geological environment. While such environments do present difficulties which require more advanced and expensive technology that is more subject to wear thus increasing startup costs, the ability to extract oil and gas from previously unreachable locations, while simultaneously increasing production in already existing vertical wells, directional drilling increases production so drastically that any increase in startup costs become negligible in comparison to the rewards.