The deviation correction trajectory of the mechanical vertical drilling system (MVDS) is very important because it final embodiment performance. However, impossible to obtain at design stage, except when using simulation methods. In this paper, tool face angle model and other theoretical models were established, respectively, method was created through coupling. Next, used simulate MVDS under t...

We propose that a new type of drill, alternately known as a Fast Mechanical-Access Drill, or Coiled Tubing Drill for Ice (CTDI), be developed for polar research. The proposed drill is similar in concept to the latest coiled tubing (CT) drills used for commercial oil and gas development. CT drills use a metal or advanced-composite tube to deliver fluid downhole to a hydraulic motor that drives a...

Stick-slip vibration reduces the drilling rate of penetration, causes early wear bits, and threatens safety downhole tools. Therefore, it is necessary to study suppression methods stick-slip achieve efficient safe drilling. Field tests show that use axial impactors helpful mitigate improve rock-breaking efficiency. However, there are many deficiencies in how impact load affects a PDC bit. In th...

A while-drilling energy harvesting device is designed in this paper to recovery along with the longitudinal vibration of drill pipes, aiming serve as a continuous power supply for downhole instruments during drilling procedure. Radial size determined through engineering field experience and geological survey reports. piezoelectric coupling model based on selected material was established via CO...

Currently, the exploration and development scope of Changqing oilfield has gradually developed to edge blocks deep systems, typically Yanchi block. However, in construction process, there are some problems such as poor well wall stability, frequent leakage prominent collapse contradiction, which seriously restricts increase drilling speed. In this paper, measures structure optimization, system ...

In conventional wireline and LWD/MWD formation testing, downhole predictions for rock fluid properties are based on simplified Darcy flow models, but only mathematical expediency. These require initially constant pressures that uniform throughout the reservoir. This limitation precludes common applications in overbalanced drilling, so supercharge or near-well invasion effects - associated with ...