The accurate prediction of wellbore temperature distribution helps to accurately estimate well pressure profile and bottom-hole pressure (BHP) which is important in the under-balanced drilling (UBD) operation. In this paper effect of temperature variation due to heat transfer of drilling fluid with the formation and also oil and gas production from the reservoir into the annulus in under-balanc...

The process of borehole drilling is a nonlinear and many dimensional process. During drilling it is possible occurrence of some complications (for example transition of drilling tool in layer with anomalous pressure). New method of identification of rock layers with anomalous pressure was proposed and tested on real plant data.

For years, drilling engineers have been faced with the challenge of wells through naturally fractured reservoirs that are present around world. During drilling, pressure at bottomhole a well is frequently intentionally higher than formation pressure, which can result in loss mud surrounding rocks. cementing, even it during because cement slurry density mud. Therefore, if natural or induced frac...

Information transmission is an important part of the wellbore trajectory automatic control system. Combined with the characteristics of the guided drilling system, drilling fluid pulse is selected as a tool for trajectory control. Negative pulse transmission of drilling fluid is one of the key technologies to realize wellbore trajectory automatic control. In this paper, the working principle of...

underbalanced drilling as multiphase flow is done in oil drilling operation in low pressure reservoir or highly depleted mature reservoir. correct determination of the pressure loss of three phase fluids in drilling annulus is essential in determination of hydraulic horsepower requirements during drilling operations. in this paper the pressure loss of solid-gas-liquid three-phase fluids flow in...