The dynamic model of a drill in drilling process was proposed and investigated in this study. To assure a good drilling quality, the vibration variation on the drill tips during high speed drilling is needed to be investigated. A pre-twisted beam is used to simulate the drill. The moving Winkler-Type elastic foundation is used to characterize the tip boundary variation in drilling. Due to the v...

The main affecting parameter for Delamination of the composites and in turn the failure of composites is the Thrust force. In the present work an attempt has been made in order to investigate the Thrust force generated during drilling of the TiO2 and ZnS filled Glass Fabric Reinforced Polymer Matrix Composites (GFRP). The volume fractions in the matrix were chosen as 1, 2 and3%. A plan of exper...

RATIONALE Retrograde drilling is a well accepted procedure for osteochondral lesion of the talus and subchondral cyst with intact overlying cartilage. It has good results in most reports. Compared to anterograde drilling, retrograde drilling can protect the integrity of the articular cartilage. The purpose of this study was to evaluate the suitability of using retrograde drilling for osteochond...

Drilling of glass fibre reinforced plastic (GFRP) composite is different from metallic materials due to its mechanical properties. The drilling of this material may generate delamination of drilled holes on workpiece. The purpose of this paper is to investigate the influence of the cutting parameters, such as cutting speed and feed rate, point angle of drill and material thickness on delaminati...

Drilling engineering is a high input and risk underground project, which needs the real-time down-hole diagnosis and forecast technique. Drilling string vibration signals contain full and complex vibration waves, which contains the vibration of the drilling string by itself, the vibration stimulated by the interaction of bit and the formation, the vibration induced by colliding between drill st...

Bone drilling is a major part of modern orthopaedic surgery which involves the internal fixation of fractured bones. The investigation of bone drilling described in this paper demonstrates the contribution of automation technology towards the study of bone strength. The aim of this preliminary investigation is to establish a relationship between bone drilling forces and measurements of bone min...

Oil and gas drilling operations use drilling fluids (mud) to lubricate the drill bit and stem, transport formation cuttings to the surface, and seal off porous geologic formations. Following completion of the well, waste drilling fluid is often applied to cropland. We studied potential changes in soil compaction as indicated by cone penetration resistance, pH, electrical conductivity (EC(e)), s...

today’s energy reauiraments have produced an increase in drilling activities all around the world. among this situation is the fact that all the operators are trying to minimize cost without reduction in quality. so, they are looking for new types of contracts between all drilling companies, contractors and suppliers until that with make agreement between them have successful operations. in thi...