Concrete strength evaluated from compression tests on cores is affected by several factors causing differences from the in-situ strength at the location from which the core specimen was extracted. Among the factors, there is the damage possibly occurring during the drilling phase that generally leads to underestimate the actual in-situ strength. In order to quantify this effect, in this study t...

vibratory drilling (vd)process is a new modern technology where longitudinal wave with high frequency (more than 16 khz) and low amplitude (usually between 2 up to 30 µm) is superimposed on the movement of cutting tool, resulting in connection and disconnection of cutting tool engagement with workpiece. in this study, in order to perform vibratory drilling process, two vibration tools are desig...

Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling w...

OBJECTIVES The purpose was to assess thermal changes and drill wear in bovine bone tissue with the use of twisted stainless steel and zirconia-based drills, during implant site preparation. METHODS A total of 100 implant site preparations were performed on bovine ribs using a surgical unit linked to a testing device, in order to standardize/simulate implant drilling procedures. Bone temperatu...

Antegrade transmalleolar drilling method is one of the options for the treatment of osteochondral lesion of talus (OLT). We present five patients who underwent tibial drilling for treatment of OLT and later developed distal tibial cystic formation induced by cartilage opening or heat necrosis during drilling. Antegrade transmalleolar drilling can be a possible option for the treatment of OLT if...

BACKGROUND Optimal tunnel placement is critical in anterior cruciate ligament reconstructive surgery, yet the method used to drill the tunnels may compromise their placement. HYPOTHESIS An independent drilling method versus a conventional transtibial drilling method will place tunnels in different locations and produce reconstructions with different kinematics. STUDY DESIGN Controlled labor...

Currently, the drilling fluid processing and recycling has gained more attention from various oilfields. Whether the waste drilling fluid’s processing and recycling is good or not will directly affect the development of oil industry. Therefore, the urgent affair is to develop and research the processing method of waste drilling fluid.This article describes various processing methods of waste dr...

Cost reduction is a driving force in the development of brownfield wells.1 It is well known that better planning leads to better execution in the drilling phase with less nonproductive time and reduced costs. This paper describes enhanced well planning workflows in light of recent software technological innovations. The technology, which enables this solution for the first time in the industry,...

Scientific selection of drill bits during drilling is a key technology to achieve high-speed drilling and reduce drilling costs. Based on the analysis of bit’s working principles and its applicable conditions and in accordance with the well conditions of ultra-deep wells in Y area of Tarim Oilfield, this study has conducted mathematical statistics on a large number of actual drilling practices ...