Experimental Study on Wear Loss of Brake Shoe based on Series Resistance

The effects of vibration on the emergency braking tribological behaviors of the brake shoe of a deep coal mine hoist were investigated in this study. The thermal, frictional and mechanical parameters of the brake shoe were obtained. The vibration characteristics of the brake shoe during emergency braking were investigated, employing multibody dynamics analysis. The effect of vibration on the emergency braking tribological behaviors (temperature and stress distributions) of brake interfaces was explored using the finite element method. The self-made tribo-brake test rig of a brake shoe was employed to reveal the friction deterioration behaviors of the brake shoe during emergency braking. The results show obvious vibrations of all brake shoes along the direction of positive braking pressure during emergency braking. The vibration causes increases in the equivalent Von Mises stress and temperature at the contact interfaces between the brake disc and the brake shoe as compared to the case of ignoring the vibration. Along the rotation direction of the brake disc, the equivalent stress and temperature of the brake disc surface present three overall rapid increases, as well as two slight decreases during emergency braking. As compared to cyclic emergency braking, continuous emergency braking exhibits more obvious tribological degradation of the brake shoe, attributed to enhanced vibration. The wear loss of the brake shoe increases with increasing emergency braking cycles and continuous emergency braking time.

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Experimental study on the effect of formulation modification on the properties of organic composite railway brake shoe

Wear ◽

10.1016/j.wear.2017.08.007 ◽

2017 ◽

Vol 390-391 ◽

pp. 283-294 ◽

Cited By ~ 5

Author(s):

Piotr Wasilewski

Keyword(s):

Experimental Study ◽

Brake Shoe

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Investigation of the Dissipation Process in Electrolytic Capacitors

ElectroComponent Science and Technology ◽

10.1155/apec.6.49 ◽

1980 ◽

Vol 6 (2) ◽

pp. 49-53

Author(s):

Leconte Cathey ◽

Keith A. Joyner

Keyword(s):

Experimental Study ◽

Thermal Properties ◽

Power Dissipation ◽

Series Resistance ◽

Peak Voltage ◽

Voltage Versus ◽

Dissipation Process ◽

Time Profiles ◽

Electrolytic Capacitors ◽

Charge Discharge

An experimental study of electrolytic capacitors was conducted, with emphasis on their thermal properties. The capacitors were subjected to charge–discharge cycles with various values of peak voltage. The observed power dissipated did not agree with that which would be expected if constant capacitance and constant effective series resistance (ESR) are assumed for the capacitors. In order to explain the discrepancy, the capacitance and ESR variations were measured with respect to voltage, temperature, and frequency. A predicted power dissipation was calculated for each capacitor; these dissipations compared favorably with those that were experimentally observed. In addition, voltage versus time profiles were measured for each unit and these were analyzed to determine the charge transport characteristics of the capacitors. The populations and mobilities of each type of charge carrier turned out to be quite similar from one capacitor sample to the next.

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Preparation and Experimental Study of Graphite Material for Water Lubricated Thrust Bearing of Nuclear Main Pump

Materials Science Forum ◽

10.4028/www.scientific.net/msf.932.102 ◽

2018 ◽

Vol 932 ◽

pp. 102-106

Author(s):

Jian Lei Wang ◽

Chen Zhang ◽

Yun Long Wang ◽

Dong Ping Wang ◽

Qian Jia ◽

...

Keyword(s):

Experimental Study ◽

Tribological Properties ◽

Thrust Bearing ◽

Property Testing ◽

Wear Loss ◽

Graphite Material ◽

Test Platform ◽

Different Types ◽

Stop Test

Based on technical difficulties of graphite water-lubricated thrust bearing such as preparation and properties detection, this paper investigated graphite bearing systematically from preparation and property testing, three different types of graphite (#1, #2 and #3) were carried out. The result indicated the tribological properties are poor if the graphitization of graphite is too high or low. The pads of water-lubricated thrust bearing are manufactured by the three kinds of graphite, and the start-stop test were carried out on a test platform for half-size bearing of nuclear primary pump. The result of start-stop test were indicated the graphitization have a visible influence on the wear loss mass of graphite pad.

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Experimental study on the restoration from a tilt-azimuth series for improvement in resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013955x ◽

1995 ◽

Vol 53 ◽

pp. 636-637

Author(s):

Norio Baba ◽

Norihiko Ichise ◽

Syunya Watanabe

Keyword(s):

Experimental Study ◽

Spherical Aberration ◽

Incident Beam ◽

Optical Parameters ◽

Beam Tilting ◽

Illumination Method ◽

Restoration Method ◽

Illumination Mode

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.

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Behavior of contact-silicided TFSOI gate structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172036 ◽

1994 ◽

Vol 52 ◽

pp. 860-861

Author(s):

N. David Theodore ◽

Juergen Foerstner ◽

Peter Fejes

Keyword(s):

Semiconductor Device ◽

Series Resistance ◽

Field Effect Transistors ◽

Silicon Layer ◽

Device Fabrication ◽

Silicon On Insulator ◽

Continuous Layer ◽

Buried Oxide ◽

Device Structures ◽

Thin Silicon

As semiconductor device dimensions shrink and packing-densities rise, issues of parasitic capacitance and circuit speed become increasingly important. The use of thin-film silicon-on-insulator (TFSOI) substrates for device fabrication is being explored in order to increase switching speeds. One version of TFSOI being explored for device fabrication is SIMOX (Silicon-separation by Implanted OXygen).A buried oxide layer is created by highdose oxygen implantation into silicon wafers followed by annealing to cause coalescence of oxide regions into a continuous layer. A thin silicon layer remains above the buried oxide (~220 nm Si after additional thinning). Device structures can now be fabricated upon this thin silicon layer.Current fabrication of metal-oxidesemiconductor field-effect transistors (MOSFETs) requires formation of a polysilicon/oxide gate between source and drain regions. Contact to the source/drain and gate regions is typically made by use of TiSi2 layers followedby Al(Cu) metal lines. TiSi2 has a relatively low contact resistance and reduces the series resistance of both source/drain as well as gate regions

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