Rheology is one of the key drilling fluid properties for controlling sag. Yet, the current understanding of the sag-rheology relationship is limited to a few general guidelines for reducing sag in the field. This paper reviews current understanding of sag and describes the initial stage of work aimed at finding a correlation between fluid rheology and sag performance under laboratory conditions...

the continuous development of global economy with decreasing in available hydrocarbon sources and increasing discovery and extraction costs due to decrease in-situ oil and gas reservoir, displays the necessity of using new techniques for the improve rate of penetration and productivity in well. nanotechnology has already contributed significantly to technological advances in the energy industri...

Analysis of the drilling fluid temperature due to heat transfer of drilling fluid with the formation in under-balanced drilling operation is the main objective of this study. Gas-liquid two-phase flow model considering thermal interaction with the formation is used to numerically simulate a well with real dimensions. In the present study, the continuity, momentum, and energy equations are devel...

Feasibility of drilling with supercritical carbon dioxide to serve the needs of deep underbalanced drilling operations has been analyzed. A case study involving underbalanced drilling to access a depleted gas reservoir is used to illustrate the need for such a research. For this well, nitrogen was initially considered as the drilling fluid. Dry nitrogen, due to its low density, was unable to ge...

The continuous development of global economy with decreasing in available hydrocarbon sources and increasing discovery and extraction costs due to decrease in-situ oil and gas reservoir, displays the necessity of using new techniques for the improve rate of penetration and productivity in well. Nanotechnology has already contributed significantly to technological advances in the energy industri...

We have devised a method, based on a parametric array concept, to create a low-frequency (300-500 kHz) collimated ultrasound beam in fluids highly attenuating to sound. This collimated beam serves as the basis for designing an ultrasound visualization system that can be used in the oil exploration industry for down-hole imaging in drilling fluids. We present the results of two different approac...

The accurate control of the wellbore pressure not only prevents lost circulation/blowout and fracturing formation by managing the density of the drilling fluid, but also improves productivity by mitigating reservoir damage. Calculating the geothermal pressure of a geothermal well by constant parameters would easily bring big errors, as the changes of physical, rheological and thermal properties...

Drilling fluid, as an essential part of the drilling process, directly affects efficiency and safety drilling. The expansion-type oil-based leak-proof plugging fluid system is a new type with advantages such plugging, good permeability, high bearing capacity, has become hot topic in research. This paper will provide detailed introduction to composition, performance, application system.

In oil and gas and geothermal installations, open channels followed by sieves for removal of drill cuttings, are used to monitor the quality and quantity of the drilling fluids. Drilling fluid flow rate is difficult to measure due to the varying flow conditions (e.g., wavy, turbulent and irregular) and the presence of drilling cuttings and gas bubbles. Inclusion of a Venturi section in the open...

Summary In the placement process of cement slurry, treatment fluids such as spacer are pumped ahead cementitious slurry to minimize contamination by drilling fluid and ensure superior bonding casing formation. The discussed in this work can harden with time act a settable spacer. This characteristic be an advantage for well integrity if some pockets left annulus. Rheological compatibility diffe...