Pressure control drilling technology through the precise control of the entire wellbore annular pressure profile, the bottom of the pressure can always maintain the safety density window, so as to achieve the purpose of safe operation. In the drilling process, the use of conventional drilling technology for drilling operations, easily lead to well, overflow and other drilling accidents. In this...

Friction drilling Process is a rotating conical tool to penetrate the work piece and create a bushing in a single step without generating chips. This work investigates the finite element modeling (FEM) of large plastic strain and high-temperature work-material deformation in friction drilling. The workmaterial deformation is very large, and both the tool and work piece temperatures are high in ...

Deep-water drilling in the Gulf of Mexico could resume within weeks under a policy by the US government, which has come under increasing criticism from the oil industry and politicians in the region over the impact of the drilling halt and worries from scientists that the full impact has not yet been assessed. Oil and gas exploration in the gulf’s deep waters has been stopped since May, when Ob...

Multiple drilling is reported to be an effective treatment for osteonecrosis of the head of femur, but its effect on intra-osseous pressure has not been described. We undertook multiple drilling and recorded the intra-osseous pressure in 75 osteonecrotic hips in 60 patients with a mean age of 42 years (19 to 67). At a mean follow-up of 37.1 months (24 to 60), 42 hips (56%) had a clinically succ...

ABSTRACT In order to evaluate the effect of countersinking on dental implants primary stability installed in low density bones, thirty dental implants were installed in the most proximal region of oxen ribs and grouped as follow: Group1: Fifteen implants installed by standard drilling with countersinking, Group2: Fifteen implants installed by standard drilling without countersinking. The gradua...

Environmental concerns surrounding drilling for gas are intense due to expansion of shale gas drilling operations. Controversy surrounding the impact of drilling on air and water quality has pitted industry and lease-holders against individuals and groups concerned with environmental protection and public health. Because animals often are exposed continually to air, soil, and groundwater and ha...

Water and gas samples were collected from (1) nine shallow groundwater aquifers overlying Marcellus Shale in north-central West Virginia before active shale gas drilling, (2) wells producing gas from Upper Devonian sands and Middle Devonian Marcellus Shale in southwestern Pennsylvania, (3) coal-mine water discharges in southwestern Pennsylvania, and (4) streams in southwestern Pennsylvania and ...

This paper presents the MAMView framework to help users and developers in understanding the data organisation in Metric Access Methods (MAM). Users and developers can explore and share dynamic and interactively 2or 3-dimensional representations of a MAM. Such representations can be the steps of a similarity query or the insertion of an object, or the data organisation in a MAM. MAMView was deve...

Heat, generated during the drilling of a dental implant site preparation, leads to a temperature rise and consequently to a thermal injury of the bone tissue surrounding the implant site, which can cause the subsequent implant failure. In this article, we present new findings related to the temperature rise during implant site drilling under real conditions on a bovine rib bone specimen. The ex...