Results 241 to 250 of about 56,879 (283)

Designing Well Paths to Reduce Drag and Torque

SPE Drilling Engineering, 1987
Summary A deviated well with an undersection trajectory (i.e., a trajectory lying below the conventional tangent section and constantly building to target) can exhibit lower drag and torque than a conventional well geometry in certain circumstances. The influence of well geometry on drag and torque is discussed, making use of the results
M. C. Sheppard, C. Wick, T. Burgess
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Drag Force, Drag Torque, and Magnus Force Coefficients of Rotating Spherical Particle Moving in Fluid

Particulate Science and Technology, 2012
The mutual influence of translational and rotational spherical particle movements in calm water was studied using experimental data and numerical simulation. Spherical balls with a density close to that of water were speeded up in special devices, which ensured the required ball rotational and translational velocity in the given plane.
Lukerchenko, N. (Nikolay), Kvurt, Y., Keita, I. (Ibrahima), Chára, Z. (Zdeněk), Vlasák, P. (Pavel)   +4 more
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Multiphase Drag Modeling for Prediction of the Drag Torque Characteristics in Disengaged Wet Clutches

SAE International Journal of Commercial Vehicles, 2014
<div class="section abstract"><div class="htmlview paragraph">The undesired Drag Torque (DT) which is developed due to the shearing of fluid film in between the disk and separator plate reduces the efficiency of a transmission and increases the fuel consumption of a car.
Shahjada Pahlovy, Syeda Faria Mahmud, Masamitsu Kubota, Makoto Ogawa, Norio Takakura   +4 more
openaire   +1 more source

Torque and Drag in Directional Wells-Prediction and Measurement

Journal of Petroleum Technology, 1984
Summary A computer model has been developed to predict drillstring torque and drag, and a versatile rotary torque meter has been built to use in calibrating the model. The principle of the predictive model is that torque and drag forces in a directional wellbore are primarily caused by sliding friction.
C.A. Johancsik, D.B. Friesen, Rapier Dawson   +2 more
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A rotational rheometer with a drag‐cup torque transducer

Journal of Polymer Science: Polymer Physics Edition, 1975
AbstractA rotational cone‐and‐plate rheometer incorporating a drag‐cup torque transducer and a frictionless, wire suspension has been designed and constructed. The instrument design provides for a controlled atmosphere for the sample, including anhydrous conditions necessary for studies on solutions of polymers in strong acids.
Guy C. Berry, Chiu‐Ping Wong
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Drag Torque in Disk Brakes: Significance, Measurement and Challenges

SAE International Journal of Commercial Vehicles, 2015
<div class="section abstract"><div class="htmlview paragraph">Drag torque is generated in disk brakes as a result of contact (dynamic friction) between brake disk and brake pads when the braking system is not actuated. Among the negative implications of drag torque are, notably, dispensable additional fuel consumption as well as increased ...
Achim Reich, Angelo Sarda, Martin Semsch
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Aeration in Lubrication With Application to Drag Torque Reduction

Journal of Tribology, 2011
The aeration of an oil film flowing between the faces of two closely spaced circular plates (one stationary, and one rotating) is examined experimentally, numerically, and with an improved lubrication model. The gap between the plates is small compared to their radii, making lubrication theory appropriate for modeling the flow.
Chinar R. Aphale, William W. Schultz, Steven L. Ceccio   +2 more
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Torque and Drag Modeling for Horizontal Openhole Completions

Journal of Petroleum Technology, 2006
This article, written by Technology Editor Dennis Denney, contains highlights of paper SPE 97079, "Torque and Drag Modeling for Horizontal Openhole Completions," by R. Rezvani, Halliburton/Sperry Sun, and B. Techentien, Halliburton Energy Services Inc., prepared for the 2005 SPE Annual Technical Conference and Exhibition, Dallas, 9–12 October.
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Drag Torque Measurement of Hard Disk Drive Spindle Motors

Asia-Pacific Magnetic Recording Conference 2006, 2006
The drag torque of a hard disk drive (HDD) is a key variable to its spindle motor. It should be accurately tested during R&D and mass productions of HDDs. This paper reviews its existing measurement methods currently used by HDD industry first. Then an effective method to measure the drag torque is introduced.
Q. Jiang, C. Bi, S. Lin
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Residual Drag Torque on Magnetically Suspended Rotating Spheres

Review of Scientific Instruments, 1972
An almost quantitative explanation of the residual drag torque on freely spinning steel spheres in magnetic suspension is given by comparing previously published experimental data with theoretical results of Keith (1963). Accordingly, the residual drag torque is mainly caused by the earth's rotation.
openaire   +1 more source