نتایج جستجو برای: drilling

تعداد نتایج: 12560  

The rate of penetration (ROP) is one of the vital parameters which directly affects the drilling time and costs. There are various parameters that influence the drilling rate; they include weight on bit, rotational speed, mud weight, bit type, formation type, and bit hydraulic. Several approaches, including mathematical models and artificial intelligence have been proposed to predict the rate o...

M. V. Dvoynikov M. V. Nutskova, P. A. Blinov

The article discusses researches performed in the Well Drilling Department of the St. Petersburg Mining University. The directions of development of the department are shown. Special attention in this article is paid to research in the field of developing drilling fluids for drilling wells in various mining and geological conditions. It is shown that the gas-liquid mixtures studied by the depar...

Filtration index of the drilling fluid is an important parameter of well drilling, especially at drilling-in the reservoirs. Standard parameter in the study of drilling fluids is static filtration index. At the same time, it is more feasible to determine dynamic filtration index, if considering actual conditions of the well. Use of polymer carbonate-weighted drilling fluids is advisable at dril...

Journal: :مجله دانشکده دندانپزشکی اصفهان 0
علی پیرنیسیانی نیما جمشیدی محسن صراف بیدآبادی نوید سلطانی adel pirjamali neisiani nima jamshidi

introduction: excessive temperature rise during drilling of the mandible for dental implant placement might damage adjacent osseous tissues. various factors affect temperature rise, including the geometrical parameters of surgical drills, one of which is the drill bit head angle. the aim of this research was to determine suitable drill bit head angle to induce minimum temperature rise during ma...

Journal: :The International journal of oral & maxillofacial implants 2017
Salah Huwais Eric G Meyer

PURPOSE It is essential to have sufficient bone bulk and density at the implant site in order to achieve good bone-to-implant contact and primary stability, which are crucial for osseointegration. A new osteotomy preparation technique was recently introduced that uses a bone preservation method that creates a layer of compacted bone along the surface of the osteotomy. The hypothesis of this stu...

Designing drilling fluids for drilling in deep gas reservoirs and geothermal wells is a major challenge. Cooling drilling fluids and preparing stable mud with high thermal conductivity are of great concern. Drilling nanofluids, i.e. a low fraction of carbon nanotube (CNT) well dispersed in mud, may enhance the mixture thermal conductivity compared to the base fluids. Thus, they are potentially ...

Journal: :British journal of sports medicine 2001
A Khashaba

Nirschl release appears to be a very successful technique for surgically suitable cases of tennis elbow. However, although the drilling or decortication aspect of the procedure was thought to be of benefit to the immediate outcome, this has not actually been confirmed. This randomised double blind comparative prospective trial shows that drilling confers no benefit and actually causes more pain...

2012
Enrique Cruz Sean Liu Jun Sun Steven B. Blanchard Armando Soto Kelton T Stewart Matthew R. Allen

Microdamage reduces bone mechanical properties and thus could possibly contribute to implant failure. The objective of this study was to investigate whether the diameter of mini-implants (MI) affects microdamage generation and whether this differs between the mandible and maxilla due to their contrasting cortical thicknesses. Methods: Maxillary and mandibular quadrants of 5 dogs were randomly a...

2013
Zhilong Wang Da Yin Yue Luo Hongjun Liang Longlong Yang Hu Lu

This study deals with onshore oilfield drilling fluid system to drill corrosion. Corrosion under static and dynamic conditions of the drilling fluid was evaluated. The effect of temperature and pressure on corrosion was examined. Corrosion was more severely affected by temperature compared to pressure. The combined effect of a deoxidizing agent and an inhibitor was observed to exhibit better pr...

2005
Leticia Curiel Álvaro Herrero Emilio Corchado Pedro Bravo

The purpose of this study is the optimization of drilling tasks in the construction of big auto-carrier storage warehouses. This is carried out by applying different Artificial Intelligence (AI) techniques: a cooperative unsupervised connectionist model (focused on the detection of some optimal drilling conditions) and software agents. These agents can collaborate to save drilling time and wast...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید