An SiCf/SiC composite has the following excellent properties: high strength, low specific gravity, and temperature resistance, which great prospects in combustion chamber of rockets or aero engines. Hole-making parts is an important processing method. Generally, water-based oil-based coolants are avoided, so dry drilling primary hole-making approach for SiCf/SiC. However, abrasion resistance ha...

control of well drilling operations poses a challenging issue to be tackled. the loss of well control could lead to the occurrence of blowout as a severe threat, involving the risk of human lives and environmental and economic consequences. conventional proportional-integral (pi) controller is a common practice in the well control operation. the small existing margin between pore pressure and f...

Neurosurgery is a very special field among the many branches of medical science. It is filled with challenges and excitement. Looking back into the history, it seems that the trephination was performed approximately 5000 years ago. Skulls are found in Europe, Oceania, and Tibet; some of these have a sharp-edge hole in them. However, the actual instruments used by the aboriginal people and their...

Abstract: This article aims to study the effects of shock-disturbed cracks on the cutting features of cone bits. By utilizing the Walsh’s model, a crack model was established for the damaged rock surrounding the induced hole, the intrusive coefficient of the cone bit was derived, and the drilling rate equation around the induced hole was formulated. The effects of crack density and disturbance ...

In this paper, we present an integrated model to find the optimum size of blast block that uses (i) a multi-criteria decision-making method to specify the applicable size of the mineable block; (ii) a linear programming method for the selection of the blasted areas to be excavated and in deciding the quantity of ores and wastes to be mined from each one of the selected blocks. These two methods...

Engineering plastics have specific properties in strength, hardness, impact resistance, and aging persistence, often used for structural plates electronic components. However, the holes made by drilling process always shrink after cutting heat dispersion due to their high thermal expansion coefficient. Drilling parameters must be discussed thoughtfully especially small-hole fabrication acquire ...

Stress concentration factors have been examined in a functionally graded material (FGM) plate with central holes in different shapes in this essay. The material properties change along the thickness of plate. ABAQUS software has been utilized for modeling of problem in which subroutine of ABAQUS sub-program was used for modeling of the targeted material. The considering shapes for hole in plate...

This present investigation uses the Taguchi and response surface methodology (RSM) for modelling and optimization of the temperature produced during bone drilling. The drilling of bone is a common procedure in orthopaedic surgery to produce hole for screw insertion to fixate the fracture devices and implants. A major problem which is encountered during such a procedure is the increase in temper...