The dogleg severity is one of the most important parameters in directional drilling. Improvement of these indicators actually means choosing the best conditions for the directional drilling in order to reach the target point. Selection of high levels of the dogleg severity actually means minimizing well trajectory, but on the other hand, increases fatigue in drill string, increases torque and d...

water soluble amphoteric graft copolymers of polysaccharide were synthesized via grafting of cationic monomer onto the sodium carboxymethylcellulose ()cmc)( and then used as a shale stabilizer in the water-based drilling fluids. accordingly, five types of cmc-graft copolymers with different ratios of acrylamide am)( and diallyldimethylammonium chloride dadmac)( were synthesized. grafting of mon...

Drilling of fiber reinforced plastics is necessary in order to assemble complex/intricate composite products. Drilling induced damage leads to high percentage of part rejection and reduced product efficiency and life. The thrust force and torque have been found to be the important factors influencing damage. In the present research endeavor, an attempt has been made to develop a fuzzy rule base...

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...

Hardened steels are commonly used in wide areas of technologies and industries. In respect of poor machinability of these steels and requirement of expensive cutting tools, study of machining economy is a matter of importance. Thus the present study deals with the economic considerations of various hole making processes. For this purpose, the hard steel samples were machined by conventional dri...

Effective cuttings transport means a better hole cleaning in drilling operations, which can increase the rate of penetration (ROP), and avoids pipe sticking, higher drag and torque problems. This paper aimed to analyze cuttings transport efficiency affected by different blade shapes of stabilizers, which is often overlooked in drilling. For this purpose, Eulerian multiphase flow model was used ...

In the last years, laser beam drilling became increasingly important for many technical applications as it allows the contactless production of high quality drill holes. So far, mainly short laser pulses are of industrial relevance, as they offer a good compromise between precision and efficiency and combine high ablation efficiency with low thermal damage of the workpiece. Laser beam drilling ...