Glass Fiber Reinforced Plastic composites have an increased application in recent days, due to its enhanced structural, mechanical and thermal properties. The heterogeneous nature of this kind of materials makes complications during machining operations. Drilling of holes in GFRP becomes almost unavoidable in fabrication. However, drilling is a common machining practice for assembly of componen...

Inverter circuits have been made by connecting two high-quality pentacene field-effect transistors. A uniform and pinhole-free 900 nm thick polyimide gate-insulating layer was formed on a flexible polyimide film with gold gate electrodes and partially removed by using a CO2 laser drilling machine to make via holes and contact holes. Subsequent evaporation of the gold layer results in good elect...

This work is devoted to the investigation of oscillations in a drilling system using an induction motor with wound rotor as a drive. It is motivated by the problems of drilling rig failures in the oil and gas industry. The study is based on a modified version of the mathematical model of a drilling rig proposed by scientists from the Eindhoven University of Technology. The model of drilling rig...

In this chapter possibilities of the improvement of drilling tool efficiency on the basis of the analysis of mechanisms of rock destruction and some methods of the information theory are considered. Physical mechanisms of destruction of hard and plastic rocks under different conditions of mechanical loading are reviewed. Some physical effects which allow to improve the efficiency of rock drilli...

Wellbore instability is one of the major problems that hamper the drilling speed in Halfaya Oilfield. Comprehensive analysis of geological and engineering data indicates that Halfaya Oilfield features fractured shale in the Nahr Umr Formation. Complex accidents such as wellbore collapse and sticking emerged frequently in this formation. Tests and theoretical analysis revealed that wellbore inst...

A system that applies a method of knowledge-intensive case-based reasoning, for repair and prevention of unwanted events in the domain of offshore oil well drilling, has been developed in cooperation with an oil company. From several reoccurring problems during oil well drilling the problem of ”lost circulation”, i.e. loss of circulating drilling fluid into the geological formation, was picked ...

The study was to evaluate the performance of different materials used in dental operative simulation and compare them with those of natural teeth. Three typical phantom teeth materials were compared with extracted permanent teeth by a nanoindentation system and evaluated by students and registered dentists on the drilling sensation of the materials. Moreover, the tool life (machinability) of ne...

Investigations over two major tectonic zones in the Hallandsås Horst, Southern Sweden were carried out in connection with a railway tunnelling project. A combination of resistivity imaging, core drilling and geophysical logging was found to provide a good overview of the variation in rock quality and detailed information on the engineering geological characteristics and genesis of the strata. R...

This paper is concerned with optimization of surface roughness when drilling of stainless steel SS304 with HSS drill. This study included drilling of SS304 with supply of Sic abrasive having grain size 650 and 1250 mesh size through abrasive slurry system. Abrasives not only used for cooling purpose but also increases the surface finish, MRR and reduce tool wear. Experiments were conducted on a...

Robotic devices and humans interact with each other and themselves at differing levels of collective responsibility. Future space exploration requires both robotic and human components, in complementary roles. Future in-situ lunar/martian resource utilization and characterization, as well as the scientific search for life on Mars, will require access to the subsurface and hence drilling. Drilli...