Abstract During an oil and gas well drilling the fluids are pumped through drill string to cool lubricate bit. This also serves purpose of bringing rock cutting back surface various other purposes like pressure control maintain bore stability. As is drilled casing lowed from caving in. results in a situation where there annular flow fluid inner pipe rotating while outer stationary. The understa...

This article presents the horizontal directional drilling (HDD) as one of most suitable technique used to reduce impact on environment during submarine pipe and cable installation process, especially in coastal area shallow waters. HDD is a drill subsea tunnel or under other designated with goal pull facility through drilled underground tunnel. With development offshore natural gas wind industr...

Due to the lower tool as the research object to analyze the vibration of the drill string, causes the loss of the low order natural frequency of the drill string and the inherent vibration mode, give rise to the distortion and error of the result from the transient analysis of the drill string. For this purpose, the whole drill string of the deep wells is studied in the article, build the mecha...

In automation flexible manufacturing systems, tool wear detection during the cutting process is one of the most important considerations. This study presents an intelligent system for online tool condition monitoring in drilling process .In this paper, analytical and empirical models have been used to predict the thrust and cutting forces on the lip and chisel edges of a new drill. Also an empi...

A key element to verify the drill-bit signal processing is the estimation of the time delay of the guided waves transmitted through the drill string from the bit to the surface. This delay can be measured from drill-bit vibrations or calculated using the mechanical properties of the drill string. The calculation of the complete solution and the exact dispersion relations requires expensive nume...

Fluoroscopy is currently the standard approach for image guidance of surgical drilling procedures. In addition to the harmful radiation dose to the patient and surgeon, fluoroscopy fails to visualize critical structures such as blood vessels and nerves within the drill path. Photoacoustic imaging is a well-suited imaging method to visualize these structures and it does not require harmful ioniz...

OBJECTIVES To investigate whether a surgeon can drill accurately a specified angle and whether surgeon experience, task repetition, drill bit size and perceived difficulty influence drilling angle accuracy. METHODS The sample population consisted of final-year students (n=25), non-specialist veterinarians (n=22) and board-certified orthopaedic surgeons (n=8). Each participant drilled a hole t...

the increasing needs for energy, its high price and its environmental impact on greenhouse gases emission and limited energy resources due to increased research on energy balance in crop production systems. the objective of this research was to compare seedbed preparation and sowing methods in wheat production in kordkoy region with respect to energy use and efficiency. fifteen wheat fields wer...