Well drilling is the only way to extract oil and gas from the earth. Drilling wells in an oil patch may be for the purpose of exploration, development, infill, injection, or reentry into existing wells. Exploration drilling is conducted to find and evaluate potential reserves in a reservoir rock. Development drilling is conducted to develop a field with proven reserves to its fullest extent of total production. Injection well drilling is conducted for the purpose of storing hydrocarbons (mainly gas), disposing of unwanted produced waters, or regaining the reservoir pressure by injecting water, steam, or gas into the reservoir. Reentry well drilling is conducted on existing wells for the purpose of deepening to lower pay zones, recompleting, or drilling laterals from the main trunk. Infill drilling is conducted to replace depleted wells or to drill additional wells so as to sustain production economics of the field.
Oil-well drilling and oil lifting are key technologies in the exploration and extraction of oil. Drilling strings and sucker rod strings are the primary tools for exploring and extracting petroleum from rock in the subsurface. Improvements in drilling technology and oil lifting technology that lower costs and increase the rate of success in finding and extracting petroleum will have a direct benefit to the world in terms of higher energy reserves, stable energy costs, and improved economic competitiveness in the drilling and service industries [1–12]. The friction dynamics of drill strings and sucker rods have had lots of critical problems associated with the quality of drilling and lifting performance, which limits tool life and productivity. This chapter presents the fundamental friction dynamics of drill string and sucker rod string. Concepts, modeling, and analysis connected with friction dynamics are presented, including advances in knowledge of the tool–rock interaction, couple axial and torsional friction dynamics, stick-slip whirl, and fully coupled dynamics of drill strings, as well as friction dynamics of sucker rods.
Well drilling generates the most serious noise pollution. During normal plant operation, a geothermal station does not emit objectionable noise. However, under emergency conditions, usually for brief periods, the possibility arises for high noise levels if it is necessary to vent steam. Simple rock mufflers are routinely installed to reduce the velocity (and the noise) of the venting steam. Table 3 shows a comparison of noise levels from a variety of geothermal operations with noises of everyday life. The data refer to plants at The Geysers in California, USA. Even a wide-open, vertically discharging well, one of the worst possible noise sources associated with geothermal operations, when heard from a distance of about one kilometre, is no worse than a typical noisy urban area. Furthermore, the routine noise of plant operation (excluding well drilling, testing, or venting) is practically indistinguishable from other background noises at about one kilometre.