One of the most significant problems encountered in machining, particularly in drilling, is that of burr formation. Burrs usually comprise of work piece material which has been plastically deformed during the machining process and projects beyond the desired edge of the work piece. The adverse effects of burrs depend on the component application but may include; stress concentration and related...

Composite materials are widely employed in the naval, aerospace and transportation industries owing to the combination of being lightweight and having a high modulus of elasticity, strength and stiffness. Drilling is an operation generally used in composite materials to assemble the final product. Damages such as the burr at the drill entrance and exit, geometric deviations and delamination are...

in this paper, after collecting the rock samples from eight mines and one high way slope, the tests for determination of dry density, uniaxial compressive strength, tensile strength (brazilian test), elastic modulus, schmidt hammer rebound number have been done on samples. in addition, in order to calculating the mean size of rock grains, quartz content, hardness and abrasivity, a thin sections...

This investigation proposes a grey-based Taguchi method to solve the multi-response problems. The grey-based Taguchi method is based on the Taguchi’s design of experimental method, and adopts grey relational analysis (GRA) to transfer multiresponse problems into single-response problems. In this investigation, an attempt has been made to optimize the drilling process parameters considering weig...

In order to service and grow in the present day of global competition, every manufacturing concern focuses mostly on two factors i.e. productivity and quality. Laser drilling is a popular non-traditional machining technique for producing large numbers of cooling holes of various sizes (less than mm diameter) and angles in modern aerotech components such as turbine blades, injector nozzles, and ...

A comprehensive investigation was carried out to minimize the cost price of the rock fragmentation process including: drilling, blasting, secondary blasting and separating the large boulders (oversize rocks) while loading, until the optimized fragmentation, powder factor and ratio of burden (B) to blasthole diameter (?h) were achieved by doing several stages of drilling and blasting practically...

This paper shows how the recently developed formulation of conformal geometric algebra can be used for analytic inverse kinematics of two six-link industrial manipulators with revolute joints. The paper demonstrates that the solution of the inverse kinematics in this framework relies on the intersection of geometric objects like lines, circles, planes and spheres, which provides the developer w...

This paper presents a study of hole quality and energy consumption in the process of drilling a thermoplastic polymeric material, polyether-ether-ketone, reinforced with 30% glass fibers (PEEK-GF30). PEEK-GF30's capacity to be machined has focused on turning operations. Studies of drilling involving thermoplastic polymeric materials have considered materials with other types of matrices, or rei...

Previous studies have established that the selection of gas extraction borehole parameters is crucial for effectiveness extraction. To more accurately determine reasonable radius boreholes in coal seam, this study was based on actual occurrence conditions body. A coal-seam gas-seepage model, considering dynamic changes permeability under gas–solid coupling conditions, constructed. It combined w...

This review highlights the influence of parameters on drilling characteristics biocomposites including natural fibers. The particular structure fibers, their hierarchized geometry, which potentially causes fibrillation, can result in an increased chance irregularity hole and a more complex mode delamination or, general terms, damage to composite. On other hand, attain effective junction laminat...