This investigation presents the effect of various parameters on foam stability and its rheological properties. The underlying idea of this experiment is generating of drilling foam with uniform bubbles. The main problem of foam using is controlling its stability during field application. The most important parameters which cause Instability in foam are gravity drainage, gas diffusion and bu...

Wellbore instability is the primary technical problem that restricts low-cost drilling of long-interval horizontal wells in shale formation Jidong Oilfield. Based on evaluation mineral composition, structure and physicochemical properties shale, this paper investigates mechanical behavior characteristics under fluid action by combining theoretical analysis, experimental numerical simulation. Du...

this investigation presents the effect of various parameters on foam stability and its rheological properties. the underlying idea of this experiment is generating of drilling foam with uniform bubbles. the main problem of foam using is controlling its stability during field application. the most important parameters which cause instability in foam are gravity drainage, gas diffusion and bubble...

The formation pressure plays a very important role in drilling engineering. So it is of great significance to predict formation pressure before drilling. In order to solve the problem, the concept of formation matrix and wellbore matrixwere put forward. Also the method of epitaxial transplantation for the regional formation pressurewas proposed. With the concept of wellbore pressure matrix, the...

Determination of the borehole and fracture initiation positions is the main aim of a borehole stability analysis. A wellbore trajectory optimization with the help of the mud pressure may be unreasonable since the mud pressure can only reflect the degree of difficulty for the initial damage to occur at the wellbore rather than the extent of the wellbore damage. In this work, we investigate...

Abstract The wellbore instability of the deep coal seam has always been a difficult problem limiting drilling engineering in Dibei area Tarim basin, China. Therefore, mechanisms and anticollapse countermeasures are investigated this study. Firstly, microstructure physical chemical properties rock studied to analyze mechanism. In addition, orthogonal cleat model 3 Dimension Distinct Element Code...

In the flowing fluid electric conductivity (FEC) logging method, wellbore fluid is replaced with de-ionized water, following which FEC profiles in the wellbore are measured at a series of times while the well is pumped at a constant rate. Locations were fluid enters the wellbore show peaks in the FEC logs, which may be analyzed to infer inflow strengths and salinities of permeable features inte...

This paper presents a wellbore-stability study of the San Andreas Fault Observatory at Depth (SAFOD) research borehole located near Parkfield, California, USA. In the summer of 2005, the SAFOD borehole was drilled successfully through the active trace of the San Andreas Fault (SAF) in an area characterized by fault creep and frequent microearthquakes. In this study, we report how the analysis o...

Recent pressure buildup analyses o f Redondo Creek F i e l d wells have been f a c i l i t a t e d by i den t i f i ca t i on o f wellbore storage. The w e l l bore storage coef f ic ient observed immediately a f t e r shut-in i s control led by the compressib i l i t y o f the two-phase wellbore f lu id , but the coef f ic ient decreases when the wellbore storage i s control led by a r i s i n...