Since Dual Gradient Drilling (DGD) is a new and advanced drilling technology, currently its methods, procedures, simulations and experiments are still underdeveloped. It requires more study, research and advanced methods on DGD systems. The motivation of the paper is to study DGD systems, design good operational drilling parameters, and work on automated DGD systems to further realize safe and ...

BACKGROUND Most studies examining the safety and efficacy of transphyseal anterior cruciate ligament (ACL) reconstruction for skeletally immature patients utilize transtibial drilling. Independent femoral tunnel drilling may impart a different pattern of distal femoral physeal involvement. PURPOSE To radiographically assess differences in distal femoral physeal disruption between transtibial ...

Drilling carbon/epoxy laminates is a common operation in manufacturing and assembly. However, it is necessary to adapt the drilling operations to the drilling tools correctly to avoid the high risk of delamination. Delamination can severely affect the mechanical properties of the parts produced. Production of high quality holes with minimal damage is a key challenge. In this paper, delamination...

Aim of the project is efficiency increase of hard rocks destruction at borehole bottom by developing drilling mud solution and evaluation of its influence on drilling process. The article presents the results of studies directed on studying of drilling mud composition (the choice of reagent concentrations, taking into account the filtration properties, structural and rheological parameters, stu...

This present investigation uses the Taguchi and response surface methodology (RSM) for modelling and optimization of the temperature produced during bone drilling. The drilling of bone is a common procedure in orthopaedic surgery to produce hole for screw insertion to fixate the fracture devices and implants. A major problem which is encountered during such a procedure is the increase in temper...

In rock drilling, bit wear is a major factor in determining bit life, the cost of drilling and may significantly influence the drilling method selected for given rock type. Effective control of bit wear can yield significant cost savings. Prediction of cuttability or drillability requires an understanding of the cutting action and the mode of wear and their interaction with the rock propertiesW...

Drilling is one of the important machining processes in hole making operations. Delamination is a vital problem during any drilling operation. It causes structural integrity reduction and poor assembly tolerance as well as potential for long-term performance deterioration. As a result, drilling of any material requires dimensional stability and interface quality. In this study, glass fibre rein...

BACKGROUND Zona pellucida opening for blastomere removal can be done by mechanical or chemical means, or by laser. So far, only limited data on the use of laser systems for zona drilling in cases of PGD are available. METHODS Results of embryo biopsy and outcome of PGD in two periods were compared. In the first period, acid Tyrode medium was used for zona drilling. In the second period, zona ...

BACKGROUND This study histologically evaluated two implant designs: a classic thread design versus another specifically designed for healing chamber formation placed with two drilling protocols. STUDY DESIGN Forty dental implants (4.1 mm diameter) with two different macrogeometries were inserted in the tibia of 10 Beagle dogs, and maximum insertion torque was recorded. Drilling techniques wer...