Plain Bearing No-Load Rotational Breakaway Torque Measurement

A differential equation is obtained for the smoothed “overall” pressure distribution around a herringbone-grooved, gas-lubricated journal bearing operating with a variable film thickness. The equation is based on the limiting case of an idealized bearing for which the number of grooves approaches an infinite number. A numerical solution to the differential equation is obtained valid for small eccentricities. This solution includes the case where the journal is undergoing steady circular whirl. In addition to the usual plain bearing parameters L/D, Λ, and whirl speed ratio ω3/(ω1 + ω2), the behavior of a grooved bearing also depends on four additional parameters: The groove angle β, the relative groove width α, the relative groove depth H0, and a compressibility number, Λs, which is based on the relative speed between the grooved and smooth members of the bearing. Results are presented showing bearing radial force and attitude angle as functions of β, α, H0, Λs, Λ, and whirl speed ratio.

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Study of Wireless Torque Measurement System Based on CC2500

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.5300 ◽

2011 ◽

Vol 383-390 ◽

pp. 5300-5303

Author(s):

Wei Liu ◽

Xiao Jie Song ◽

Wen Gang Chen

Keyword(s):

Signal To Noise Ratio ◽

Digital Data ◽

Measuring System ◽

Instrumentation Amplifier ◽

Torque Sensor ◽

Torque Measurement ◽

Analog To Digital ◽

Wireless Transceiver ◽

Precision Measuring ◽

Transmission Shaft

It’s very difficult to get high precision measuring result using contact torquemeter because of very low signal-to-noise ratio. To overcome this defect, a wireless torque measuring system is designed based on CC2500. This system uses strain gauge torque sensor to measure the surface principal stress of the transmission shaft, and get the maximum shearing stress, and then the torque that the transmission shaft bears. The weak output signal of torque sensor is magnified by the instrumentation amplifier AD623, and sent to the analog-to-digital convertor. These digital data are transmited to the portable receiving terminal by the wireless transceiver chip CC2500. The dynamic wireless torque measurement is realized by this system.

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Validierung einer optischen Drehmomentmessung*/Validation of an optical torque measurement

wt Werkstattstechnik online ◽

10.37544/1436-4980-2017-09-28 ◽

2017 ◽

Vol 107 (09) ◽

pp. 590-593

Author(s):

T. Schneider ◽

J. Wortmann ◽

B. Eilert ◽

M. Stonis ◽

L. Prof. Overmeyer

Keyword(s):

Measurement Method ◽

Rotation Angle ◽

State Of The Art ◽

Torque Sensor ◽

Torque Measurement ◽

Research Project ◽

Industrial Sectors ◽

Current State ◽

Stand Der Technik ◽

Optical Torque

Das Erfassen von Drehmomenten durch Sensoren sowie das Erzeugen von Drehmomenten stellen eine wichtige Basis für viele Industriezweige dar. Im Rahmen eines Forschungsprojektes wurde ein optisches, berührungsloses Messverfahren zur absoluten Drehwinkel- und Drehmomentmessung entwickelt. Zum Vergleich mit dem aktuellen Stand der Technik wurde ein Versuchsstand aufgebaut sowie ein Referenzdrehmomentsensor eingesetzt. Die Ergebnisse dieser Validierung werden in diesem Fachaufsatz vorgestellt.   The measurement of torque via sensors as well as the generation of torque are the basis of many industrial sectors. Within a research project an optical and non-contact measurement method to detect the absolute rotation angle and torque was developed. For comparison with the current state of the art torque sensors a test stand was built and compared to a reference torque sensor. The results of this validation are presented in the present paper.

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An Experimental Study of Compatibility for Metallic Inserts Bonded into CFRP Laminates Soaked in Aircraft Fuel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1095.518 ◽

2015 ◽

Vol 1095 ◽

pp. 518-522

Author(s):

Xue Mei Chen ◽

Jing Liu ◽

Jing Xu ◽

Hui Zhang ◽

Feng Tao He ◽

...

Keyword(s):

Cost Effective ◽

Structural Components ◽

Interference Fit ◽

Cfrp Laminates ◽

Aircraft Fuel ◽

Mechanical And Physical Properties ◽

Series Of Experiments ◽

Breakaway Torque ◽

Torque Values ◽

Push Out

CFRP laminates are used for various aircraft structural components because of their good mechanical and physical properties. Metallic inserts are one kind of aerospace fasteners, which are usually installed in the metallic components by an interference fit. However, when metallic inserts are installed in the CFRP laminates by the traditional installing way, delamination and low efficiencies are troublesome. Therefore, excellent quality and cost effective installing metallic inserts into the CFRP laminates remains a challenge. In this paper, a series of experiments were carried out to study the compatibility for metallic inserts bonded into the CFRP laminates soaked in the aircraft fuel. The experimental results show that the push-out values and breakaway torque values of metallic inserts bonded in the CFRP laminates soaked in the fuel are not reduced compared with these values of sample was not prepared in that way.

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Upper Ball Joint Force Variations due to Riser Tensioner and Vessel Motions—Part II: Analysis and Computer Simulation

Journal of Energy Resources Technology ◽

10.1115/1.2905758 ◽

1990 ◽

Vol 112 (3) ◽

pp. 200-207 ◽

Cited By ~ 1

Author(s):

T. J. Kozik ◽

J. E. Lowell ◽

A. Ertas

Keyword(s):

Computer Simulation ◽

General Equation ◽

Ship Motion ◽

Joint Motion ◽

Ball Joint ◽

Joint Force ◽

Field Operation ◽

Breakaway Torque ◽

Cable Forces

An analysis of the variation of forces acting on the upper ball joint of a riser string due to the drill ship motion and riser tensioner dynamic has been conducted. The analysis includes the effect of breakaway torque on the tensioner sheaves while assuming vessel and upper ball joint motion to be independent. General equation for the tensioner cable forces and for the forces exerted on the riser upper ball joint by the ship joint-tensioner system derived in Part I are solved. The variation in the tensioner cable forces is compared to data generated in field operation.

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