نتایج جستجو برای: drilling rate estimation

تعداد نتایج: 1209308  

Journal: :The Journal of bone and joint surgery. British volume 2002
M Piska L Yang M Reed M Saleh

An innovative Kirschner (K-) wire point was developed and compared in fresh pig femora in terms of drilling efficiency and temperature elevation with the trochar and diamond points currently used in clinical practice. The tips of thermal couples were machined to the defined geometry and the temperature measured during drilling. Using the same drill speed (rev/min) and feed rate, the new K-wire ...

2018
Yang Liu Joseph Páez Chávez Ekaterina Pavlovskaia Marian Wiercigroch

This paper studies a position feedback control strategy for controlling a higher order drifting oscillator which could be used in modelling vibro-impact drilling. Special attention is given to two control issues, eliminating bistability and suppressing chaos, which may cause inefficient and unstable drilling. Numerical continuation methods implemented via the continuation platform COCO are adop...

Journal: :Integrated environmental assessment and management 2008
Jerry M Neff

Drilling mud and associated drill cuttings are the largest volume wastes associated with drilling of oil and gas wells and often are discharged to the ocean from offshore drilling platforms. Barite (BaSO4) often is added as a weighting agent to drilling muds to counteract pressure in the geologic formations being drilled, preventing a blowout. Some commercial drilling mud barites contain elevat...

2013
Xiaodong Bai Xu Wang Xiaolin Pu

In the prospecting and drilling processes of gas and oil, if added into the drilling fluids, the latex nanoparticles can improve the performance of the drilling fluids. In this paper, methyl methacrylate (MMA) acts as a monomer and the combination emulsifier is a certain proportion of OP-10, RH and T-80. PMMA latex nanoparticles have been polymerized through the method called microemulsion poly...

1998
H. S. Liu B. Y. Lee Y. S. Tarng

The paper presents an in-process prediction of corner wear in drilling operations by means of a polynomial network. The polynomial network is composed of a number of functional nodes and well organized to form an optimal network architecture using an algorithm for synthesis of polynomial networks (ASPNs). Thrust force or torque in drilling operations has been correlated with corner wear in this...

2016
Matthias Putz Aniruddha Gupta Helen Ascroft Stuart Barnes

Ultrasonic assisted drilling (UAD) has been reported effective for thrust force reduction during drilling of CFRP resulting in lower exit delamination. However, this process is not fully understood in relation to machining theory. This work focused on understanding the separate effects of chisel and cutting edges during UAD in comparison with conventional drilling (CD). Experiments were perform...

In this research, the effects of the rotational speed, feed rate, tool material and lubricants on the tool life and the hole quality are studied in the frictional drilling of the titanium sheets. The friction drilling tests are performed on a CNC milling machine. Furthermore, 5 specimens are selected and their metallurgical structures are studied. The results show thatamong the input parameters...

Journal: :The Annals of Statistics 2015

2003
Z. Yong R. Kovacevic

A general model is pre~nted for the simulation of a drilling process by abrasive waterjet. The conventional constitutive equation for the erosion rate of a single particle penetrating into a solid target is extended and applied to millions of particle strikes, taking into consideration their erosion histories. The theoretical advancement of this model reflects the inherent damping effect that o...

Journal: :iranian journal of medical sciences 0
mohammad ebrahim parsanezhad afsoon zarei abdolreza rajaeefard vivian frank ernst hienrich schmidt

background: currently clomiphene citrate is the first-line treatment to induce ovulation in women with polycystic ovarian syndrome (pcos). surgical therapy with laparoscopic ovarian drilling (lod) may avoid or reduce the need for gonadotropins.   objective: to determine the effectiveness and safety of lod compared with ovulation induction in subfertile women with clomiphene-resistant pcos.   se...

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