Drilling-induced delamination is among the major concerns of applying the fiber-reinforced composite materials in various industries. Core drill ossesses the advantage for reducing the delamination by distributing the drilling thrust force toward the drill periphery. The thrust force of core rill varying with the conditions in drilling carbon fiber reinforced plastic (CFRP) is experimentally in...

Agave is the one of the abundantly available plant in India. The wide application of agave reinforced composite plate necessitate the joining of two plates together. For making such joint drilling of those plates is required. Drilling of natural fiber composites is different from the other metals because of its mechanical properties. The major problem faced in drilling of theses natural fiber c...

Good flow and pressure control is essential for successful Underbalanced Drilling (UBD) operations. This work evaluates the use of Model Predictive Control (MPC) for integrated control of well conditions and the topside separation system during UBD. The downhole well pressure, separator liquid levels, and the separator pressure are controlled by manipulation of the rig pump, the choke, and the ...

Background: The present study was conducted to quantify the relationships between bone drilling process parameters(i.e., feed rate, resting time, exit rate, and drill bit diameter) and drilling outcome parameters (i.e., thrust force andmaximum temperature).Methods: This study utilized 10-cm cortical bovine samples to evaluate the effects of four independent parameters,in...

BACKGROUND Avascular necrosis of femoral head (AVNFH) typically presents in the young adults and progresses quickly without proper treatments. However, the optimum treatments for early stage of AVNFH are still controversial. This study was conducted to evaluate the therapeutic effects of multiple small-diameter drilling decompression combined with hip arthroscopy for early AVNFH compared to dri...

context in order to restore ovulation, puncturing ovaries with a needle powered by electricity, under laparoscopic observation, in women with anovulatory infertility with polycystic ovarian syndrome is called laparoscopic ovarian drilling (lod). although peri-adnexial adhesion after the surgery is inevitable, there is lack of evidence regarding the clinical significance. the objective of the pr...

Most oil and gas leases allow the operator to extend possession for an indefinite period by establishing production in paying quantities. We show how this option to “hold by production” (HBP) stimulates the drilling of many wells that would otherwise be uneconomic. Although such wells may superficially appear to be poor investments, in fact they contribute to shareholder value. We also show, ho...