摘要:

Dynamic whirl in well-aligned, fully liquid-lubricated end-face seals is analyzed and tested. As with whirl of journal bearings, seal whirl occurs under lightly loaded conditions, in this case controlled by balance ratio.

ISSN:0569-8197    

DOI:10.1080/05698198208983057

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Flywheels for the storage and subsequent release of energy in general involve the suspension of rather large masses rotating at speeds limited by the strength of the flywheel material. Since drag torque on the flywheel represents an undesirable energy drain during storage, windage can be eliminated by operation in a vacuum, leaving bearing drag as a significant item. Using a vertical shaft configuration, a passive repulsion-type permanent-magnet thrust bearing is virtually frictionless while small, low-loss, oil-lubricated pintle bearings maintain the shaft radially. This paper discusses the analytical design of the passive magnetic-thrust bearing, including its nonrotating damper. Reliability of the system is high since no servo-control system is required.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in San Francisco, California, August 18–21, 1980.

ISSN:0569-8197    

DOI:10.1080/05698198208983058

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Prediction of the wear rate of rails on curves is becoming an increasingly important requirement as maintenance costs rise. One possible method of achieving this aim is to relate wear behavior to contact forces and creepages which can be evaluated using existing theoretical analyses of wheel/rail contact. Such a relationship can only be derived from laboratory experiments and this paper describes the results of some dry wear tests in which a rail/tire steel combination was tested over a range of creepage (1–10 percent) and contact stress (500–1300 Nmm-2) conditions. A particular feature of the experimental technique was the use of an air blast to cool and clean the specimens.

ISSN:0569-8197    

DOI:10.1080/05698198208983059

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The Penn State microoxidation test was used to study the effets of metals—copper, brass, aluminum, stainless steel, lead, and low-carbon steel—on the high-temperature oxidation of two esters di-2-ethylhexyl sebacate and trimethylolpropane triheptanoate. The results demonstrate that metal corrosion and sludge formation are interrelated and are greatly accelerated by intimate contact of air, lubricant and metal surface.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in San Francisco, California, August 18–21, 1980.

ISSN:0569-8197    

DOI:10.1080/05698198208983060

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Several models for adsorbed films on metal surfaces have been proposed, such as monolayers and multilayers. For these films, the effect of solvent molecule is not sufficiently taken into consideration.

ISSN:0569-8197    

DOI:10.1080/05698198208983061

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Tribochemical surface reactions were kinetically analyzed using a radioactive tracer technique. Radioactive dibenzyl disulfide labeled with sulfur-35 was used as an additive, steel disks were used as specimens. To investigate the effects of the base-oil viscosity, four mineral oils having different viscosities were used as the base oils.

ISSN:0569-8197    

DOI:10.1080/05698198208983062

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The liquid phase adsorption and decomposition of dibenzyl disulfide and dibenzyl monosulfide on iron powder from hexadecane has been studied as a function of time from 130°C-170°C. Products of decomposition have been identified. The rate of decomposition is pseudo first order for each compound for more than 50 percent decomposition. Activation energies have been calculated from the temperature dependence of the pseudo first order rate constants. Some of our results differ from those of previous workers.

ISSN:0569-8197    

DOI:10.1080/05698198208983063

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

This paper describes a technique to determine the effective coefficient of dynamic friction from experimental data. The experiment consists of a rod that is being inserted in a test vessel which is subjected to a sinusoidal vibration input. The rod is impacted by three bushings. The actual impact forces are measured with three strain bolts per bushing.

ISSN:0569-8197    

DOI:10.1080/05698198208983064

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The performance of miniature instrument bearings in aircraft and marine guidance system is adversely affected by the presence of trace contaminants on the contacting surfaces. Effective cleaning of such bearings prior to assembly in these critical system is, therefore, of utmost importance. The authors' previous study critically examined the specific effects of the various current Navy solvent-cleaning procedures on specially cleaned bearing steel reference surfaces. In the present study, reference surfaces of 440C bearing steels were coated with very thin films of either a formulated synthetic hydrocarbon or a formulated polyol ester instrument lubricant and characterized by wettability, Auger electron and X-ray photoelectron spectroscopies. These coated surfaces were subjected to standard sequential cleaning procedures as well as to individual solvents at two Navy facilities, and then reanalyzed by the same methods, including Fourier transform infrared spectroscopy. Results are discussed in terms of cleaning efficiency, recontamination and types of random contamination.Presented as an American Society of Lubrication Engineers paper at the ASME/ASLE Lubrication Conference in San Francisco, California, August 18–21, 1980.

ISSN:0569-8197    

DOI:10.1080/05698198208983065

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The paper describes tests to determine whether two methods of surface hardening, sulfinuz and tufftride, improved the lubricated wear properties of a crank-shaft steel. Very pure hexadecane was used as lubricant in a modified ball and triplane test machine. The surprising result was that wear rate increased logarithmically with actual contact temperature up to 160°C when it dropped two orders of magnitude. Below 160°C, the wear debris was red ferric oxide Fe203,· beyond 160°C it changed to the much softer magnetite Fe304. Approximate figures for the energy of the two (mild) wear processes were obtained, 12–15k cal/g mole for Fe203and ˜25k cal/g mole for Fe304. No explanation for the 160°C transition, which was independent of speed and contact pressure, could be found.

ISSN:0569-8197    

DOI:10.1080/05698198208983066

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor