During exploration for oil and gas, a technical drilling fluid is used to lubricate the drill bit, maintain hydrostatic pressure, transmit sensor readings, remove rock cuttings and inhibit swelling of unstable clay based reactive shale formations. Increasing environmental awareness and resulting legislation has led to the search for new, improved biodegradable drilling fluid components. In the ...

K e y w o r d s F o u r t h g r a d e fluid, Unsteady flow, Lie symmetries. 1. I N T R O D U C T I O N In recent years, considerable efforts have been usefully devoted to the s tudy of flow of nonNewton ian fluids. This is ma in ly due to their m a n y appl icat ions in pe t ro leum drilling, manufactu r ing of food and paper, and other similar activities. A vast a m o u n t of l i te ra ture i...

This paper examines the diverse nature of user reactions to information technology (IT) within the social-historical context of its organizational use. Employing activity theory as a conceptual framework, we conduct an interpretive analysis of physicians work, perceptions, and IT usage experience at a large community hospital to understand why some of these physicians were favorably disposed to...

This paper gives an overview on the potentials of numerical simulations for understanding dynamics in laser material processing. After a short introduction into the model, simulation results on several processes like laser beam deep penetration welding, drilling or cutting are presented. Furthermore simulation results are compared with experimentally obtained data.

Managed pressure drilling is a sophisticated pressure control method which is intended to meet increasingly high demands in drilling operations in the oil and gas industry. With this method, the well is pressurized and the drilling mud is released through a control choke which can be used to actively control/reject pressure variations. Such a control system needs to handle several disturbances,...

It is not possible to directly measure the total mass of gas and liquid in the annulus and geological properties of the reservoir during petroleum exploration and production drilling. Therefore, these parameters and states must be estimated by online estimators with proper measurements. This paper describes a nonlinear Moving Horizon Observer to estimate the annular mass of gas and liquid, and ...

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.

Abstract Polycrystalline Diamond Compact (PDC) bit has been used widely in drilling operations since a long time ago. However, the utilization of this Indonesia’s geothermal just recently started 2016, thanks to rapid development PDC cutter grades and shapes last decade. Prior that, operation relied on Tungsten Carbide Insert (TCI) drill hard formations. The crushing action insert is very durab...

Determining the optimum input parameter settings (temperature, rotational velocity and feed rate) in optimizing the properties (strength and time) of the nano-drilling process can result in an improvement in its environmental performance. This is because the rotational velocity is an essential component of power consumption during drilling and therefore by determining its appropriate value requ...