During the past decade, polymer nanocomposites have emerged relatively as a new and rapidly developing class of composite materials and attracted considerable investment in research and development worldwide.Direct machining of polymers can be an option for personalized products and for manufacturing product samples. To obtain high quality products and reduce machining costs, it is very importa...

Blast furnace slag (BFS) was added into drilling fluid as a mud cake modifier (MCM) for the reuse of BFS. The effects of MCM on drilling fluid rheology and shear strength of cementformation interface (SSCFI) were evaluated. The experimental results showed that the optimized formula of the drilling fluid has 1.0 wt% MCM. The simulation results showed that SSCFI increased significantly with the a...

During summer 2012 Shell performed exploratory drilling at Sivulliq, a lease holding located in the autumn migration corridor of bowhead whales (Balaena mysticetus), northwest of Camden Bay in the Beaufort Sea. The drilling operation involved a number of vessels performing various activities, such as towing the drill rig, anchor handling, and drilling. Acoustic data were collected with six arra...

This paper presents how to model technical and human errors and how the two error types are integrated in one common model. Human errors were modeled as an integral part of the organization’s ability to handle failures, while technical errors were embedded as an integral part of the oil well drilling operation. To reduce the number of offshore accidents there is a continuous focus on safety imp...

A 5,000-m-long, 15-in (38-cm) outer-diameter, full-scale pipe was deployed from the large Moon Pool of the Hughes Glomar Explorer (Fig. 1) while a deep-ocean mining system operated from the ship in the North Pacific Ocean in 1976 and 1979. From the standpoint of design as well as operation, one of the most critical parameters in deep-ocean mining and deep-ocean drilling is the behavior of the p...

Background: Drilling is one of the most widely used process in orthopaedic surgical operation and the same drill bit is used a number of times in hospitals. Using the same drill bit a several times may be the cause of osteosynthesis and osteonecrosis. Methods: In the present work, the effect of repeated orthopaedic surgical twist drill bit on the tool wear, force, torque, temperature and chip m...

The Veria operation is a non-mastoidectomy technique for cochlear implantation. It uses the transcanal approach to the middle ear and the cochlea. The steps of the procedure are: (1) endaural approach, that offers a wide accessibility to the middle ear structures; (2) inspection of the middle ear anatomy; (3) straightening of the postero-superior bony canal wall, which is usually concave; (4) p...

Drilling is the most frequently employed operation of secondary machining for fiber-reinforced materials owing to the need for joining structures. Delamination is among the serious concerns during drilling. Practical experience proves the advantage of using such special drills as saw drill, candle stick drill, core drill and step drill. The experimental investigation described in this paper exa...

A novel device is described for efficiently harvesting bone marrow in bone marrow transplantation that uses a newly developed passive flexible drilling unit and suction mechanism. The device reduces the invasiveness of bone marrow harvesting by collecting stem cells from the iliac bone with minimal punctures and by reducing the operation time and the contamination by T cells. The device is inse...

control of well drilling operations poses a challenging issue to be tackled. the loss of well control could lead to the occurrence of blowout as a severe threat, involving the risk of human lives and environmental and economic consequences. conventional proportional-integral (pi) controller is a common practice in the well control operation. the small existing margin between pore pressure and f...