Optical and medical devices require microdrilling of holes on glass. Brittle fracture occurs during the drilling. Cone and radial cracks are generated due to impact load and walking when a drill hit a glass to make a hole. To produce good holes without cracks and fracture, a condition monitoring of glass drilling processes is required. In this paper, to develop a costeffective direct monitoring...

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...

In this paper we present an algorithm suitable for the condition monitoring of a manufacturing drilling process that will be able to detect tool wear and impending failure. The algorithm is based around a Hidden Markov Model (HMM) [5] which is trained on “normal” data obtained from the early stages of the lifetime of a drill operating under a particular drilling condition (defined by rotation s...

The change from steerable motor to rotary steerable system has been both technically and commercially successful in Lybia. Through these case histories the paper will demonstrate benefits resulting from the use of rotary steerable systems that have led to a step change in overall drilling performance in the Middle East. This paper describes the successful introduction and application of a rotar...

A detailed understanding of the drilling system and the drilling control is required to correctly interpret rock mass conditions based on monitored drilling data. This paper analyses data from hydraulic in-the-hole (ITH) drills used in LKAB’s Malmberget mine in Sweden. Drill parameters, including penetration rate, percussive pressure, feed pressure, and rotation pressure, are monitored in under...

Subchondral drilling and microfracture are bone marrow stimulation techniques commonly used for the treatment of cartilage defects. Few studies to date have examined the technical variants which may influence the success of the cartilage repair procedures. This study compared the effect of hole depth (6 mm vs. 2 mm) and hole type (drill vs. microfracture) on chondral defect repair using a matur...

a r t i c l e i n f o a b s t r a c t A logging-while-drilling (LWD) system is usually deployed in the oil drilling process in order to provide real-time monitoring of the position and orientation of a hole. Encoded signals including the data coming from down-hole sensors are inevitably contaminated during their collection and transmission to the surface. Before decoding the signals into differ...

Abstract The first step of implanting teeth is to drill a hole in the jaw bone. Excessive temperature produced during drilling is one of the destructive factors for bony tissue. If the temperature generation during surgical drilling exceeds the critical temperature, it could lead to osteonecrosis. This research intends to study drilling parameters such as drilling speed, feed rate, cooling con...