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Drilling operations in deep and ultradeep water are increasing around the world. The development of these substantial prospects provides many challenges and requires the integration of knowledge with prudent designs at different stages of the well development. Also, more wells are drilled in rotary steerable mode and other instrumented bottom-hole assemblies. All of these tools need power, which is stored in batteries. Because the downhole power supply is limited for these tools, an alternate mode of energy supply is needed so that these tools can remain downhole for long hours. This paper examines a new energy source extraction method using the hydraulic energy obtained from the circulated drilling fluid when downhole motors are used. [DOI: 10.1115/1.2794773]

The drive for energy independence has created a window of opportunity for innovations in oil recovery. New artificial lift methods like progressing cavity pumping have been successfully applied to downhole pumping applications. The multilobe pumps are also making inroads into the industry to be used under different operating conditions. Although the design has been mainly based on empirical standards and trial and error modifications, a more phenomenally optimum design of the pump is required to achieve a high efficiency standard. The optimal relationship between the pitch and the diameter of the housing is obtained to achieve a maximum flow rate for multilobe pumps. [DOI: 10.1115/1.2358142]

Recent increase in application of horizontal wells and in particular underbalanced drilling, has triggered the necessity of a powerful pneumatic downhole motor. To enhance the technology and make the system effective, a mathematical model is required to identify the opportunities for the modification of power section design. It is well known that the performance of positive displacement motor operating on compressible fluid drops down drastically as compared to the operation under incompressible fluids. The frequent motor replacement during the operation incrementally increases the operating cost despite deriving potential benefits from underbalanced drilling.

Characterization of formation while drilling continues to be a challenge to the engineers. When a well kicks while drilling, evaluation of pore pressure and the corresponding kill mud density is of critical importance for the safety of the drilling crew and mechanical integrity of the wellbore. Besides the estimation of these parameters, it will be beneficial to estimate the thickness of the kicking formation prior to drilling. This helps to drill safely and carefully through the potentially active kicking formation. In this paper, it is shown how to calculate the thickness of the kicking zone with the limited information available at the time of an oil/gas kick. A method of data analysis (obtained on a kicking well) to estimate the formation thickness of the kicking zone is presented. Illustrative examples including actual field cases are described and analyzed.