Drilling-induced delamination often occurs both at the entrance and the exit of the workpiece during drilling of composite material. Investigators have studied analytically and experimentally that delamination in drilling can be correlated to the thrust force of the drill. With a pre-drilled pilot hole, the delamination can be reduced significantly. Early reference reported models of drilling-i...

Drilling fluid is the most important lifeline of the drilling operation, that main task is facilitate the cuttings removal of the drilling. There are varieties of drilling fluids such as sodium bentonite based-drilling fluid is called “mud” and drilling foam or surfactant based-drilling fluid is called “soap”. The present work aims are study on the modified drilling mud properties by using the ...

Deep brain stimulation (DBS) is performed by burr hole surgery. In microelectrode recording by multi-channel parallel probe, because all microelectrodes do not always fit in the burr hole, additional drilling to enlarge the hole is occasionally required, which is time consuming and more invasive. We report a stereotactic burr hole technique to avoid additional drilling, and the efficacy of this...

Micro drilled holes are utilized in many of today's fabrication processes.Precision production processes in industries are trending toward the use of smaller holeswith higher aspect ratios, and higher speed operation for micro deep hole drilling. However,undesirable characteristics related to micro drilling such as small signal-to-noise ratios,wandering drill motion, high aspect ratio, and exce...

This investigation was undertaken to determine the relative effects of recommended land spraying while drilling (LWD) loading rate application for a source of water-based drilling waste material on selected soil properties and phytotoxicity. Drilling waste material was obtained from a well where a nitrate gypsum water based product was used to formulate the drilling fluid. The fluid and associa...

This paper presents a time-varying sliding mode adaptive controller in order to handle the stick-slip oscillation of nonlinear rotary drilling system. The time-varying sliding mode controller with strong robust has two time-varying sliding surfaces, one of them induced time-varying integral sliding mode control can control the transient stage of the rotary drilling system and ensure the system ...

In order to carry out a series of key basic researches, a scientific ultra-deep drilling plan is being undertaken in China. Wellbore temperature is one of the key factors during the drilling process. In this paper, we established a twodimensional transient numerical model to predict the ultra-deep wellbore temperature distributions during circulation and shut-in stages. The simulation results i...

Automatic inspection of petroleum well drilling has became paramount in the last years, mainly because of the crucial importance of saving time and operations during the drilling process in order to avoid some problems, such as the collapse of the well borehole walls. In this paper, we extended another work by proposing a fast petroleum well drilling monitoring through a modified version of the...

Abstract: The purpose of this study is to produce scarf joint through explosive welding process (EXW). The scarf weld is a process in which the final bond interface is oblique. With applying the explosive welding technique, this joint can create a metallic bond between similar or dissimilar metals. In this study, chamfered end of aluminum and copper plates were joined explosively and named scar...

A new method for improving the efficiency of laser drilling has been developed. Two synchronized free-running laser pulses from a tandem-head Nd:YAG laser are capable of drilling through 1/8-in-thick stainless-steel targets at a standoff distance of 1 m without gas-assist. The combination of a high-energy laser pulse for melting with a properly tailored high-intensity laser pulse for liquid exp...