摘要:

The data base for this study consists of the 448 life tests performed at the authors' laboratories during the four phases of an experimental program on chemical effects in contact fatigue sponsored by the Research Committee on Lubrication of ASME. Three papers have been published on the results obtained through Phase III. This paper presents statistical analyses of the combined tests and selected subsets of special interest. Eleven performance equations are given, with contact fatigue life as the measure of performance and with a number of material, lubricant, and operating factors (type of steel, surface finish, base oil, additive, moisture, slip, speed, stress, several covariates) as predictive variables. Log-normal and Weibull equations for fatigue life are compared.Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982897

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The use of ring type oil seals in modern turbo-compressors is a standard design procedure which has evolved as a result of experimental testing and field experience. Originally, major concerns were inner-seal leakage and losses associated with the fluid-film friction in the seal oil film. More recent applications of oil seals have been in compressors which run in excess of double the first shaft bending peak response speed. This fact has focused attention on the hydrodynamic characteristics of the oil seals. This paper presents a method of analyzing high-pressure ring type oil seals which enables the design engineer to determine the seals' influence on rotor-bearing stability. The results of the analysis are used in a multi-mass flexible rotor stability analysis to show how the oil seals can produce a zone of shaft-whip instability in high-speed turbo-compressors. Experimental results are presented which clearly indicate the presence of shaft whip instability before oil seal modifications and its total absence for the same conditions using an improved seal design.Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982898

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The temperature distribution in spur gears operating in a state of thermal equilibrium is solved by using a finite element method. The effects of various dimensionless parameters on bulk temperature are shown. A table is provided which can be used to predict the bulk temperature on gear teeth, once the heat transfer coefficients and frictional heat input is estimated. Theoretical results for estimating heat transfer coefficients and frictional heat are also summarized.Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982899

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Ferrographic analysis was used to determine the types and quantities of wear particles generated during accelerated rolling contact fatigue tests. The NASA five-ball rolling contact fatigue tester was used. Ball specimens were made of AMS 5749, a corrosion resistant, high-temperature bearing steel. The lubricant was a super-refined naphthenic mineral oil. Conditions included a maximum Hertz stress of 5.52 × 109Pa and a shaft speed of 10 000 rpm. Four types of wear particles were observed; normal rubbing wear particles, fatigue spall particles, spheres, and friction polymer.Presented as an American Society of Lubrications Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982900

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

It will be noticed that the suction of air occurs to the rubbing portion of the lip of an oil seal, which is operating under sealing condition. For the purpose of studying sealing phenomena of an oil seal in this paper, the suction volume per an unit time,[Qbar]of lubricating oil instead of air is used as a means of estimating the sealing status. It becomes clear that there is the relation,[Qbar]αG1/2, whereinGis nondimensional parameter of oil seal, and that suction coefficient of oil,K (=[Qbar]/uD2G1/2, whereinuandDare sliding velocity of between shaft and seal and shaft outer diameter, respectively, depends on the sealing characteristic constant,Φ, the surface roughness of the rotating shaft and its eccentricity.Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982901

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Thick intermediate films or third bodies with high load-carrying capacity are generated through wear by different materials. A balance thus naturally exists between the material wear rate and the protection afforded by these compacted wear debris films. The length of a specimen situated parallel to the sliding motion or wear debris transport direction, necessarily plays a role different from its width. For the same unit, loading material wear protection increases with length and is independent of width. The wear problem can, therefore, be approached with two-dimensional models. Debris motion explains why wear data obtained with the same materials on machines with specimens of different shapes are difficult to correlate.Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982902

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A radioactive tracer technique was used to investigate a tribo-chemical surface reaction obtained by a thrust collar type friction Machine. Radioactive dibenzyl disulfide labeled with sulfur-35 was used as an additive. Steel and copper disks were used as friction specimens.

ISSN:0569-8197    

DOI:10.1080/05698197908982903

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A test program was carried out to evaluate several new high-temperature friction materials for use in aircraft disk brakes. A specially built test apparatus utilizing a disk brake and wheel half from a small jet aircraft was used. The apparatus enabled control of brake pressure, velocity and braking time. Tests were run under both constant and variables velocity conditions and covered a kinetic energy range similar to that encountered in aircraft brake service.

ISSN:0569-8197    

DOI:10.1080/05698197908982904

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

An investigation was conducted to determine the nature of the deformation and fracture of silicon carbide and its effects on friction properties. Friction experiments were conducted with hemispherical and conical diamond riders sliding on the basal plane of silicon carbide. The results indicate that, when deformation is primarily elastic, the friction does not depend on crystallographic orientation and there is no detectable fracture or crocking. When, however, plastic deformation occurs, silicon carbide exhibits anisotropic friction and deformation behavior. Surface fracture crack patterns surrounding wear tracks are observed to be or three types. The crack-geometries of two types are generally independent of orientation, the third crack, however, depends on the orientation. All surface cracks extend into subsurface. Anisotropic friction, deformation and fracture on the basal plane are primary controlled by the slip system {101¯0} ⟨112¯0⟩ and a cleavage of {101¯0}.Presented as an American Society of Lubrication Engineers paper at the ASLE/ASME Lubrication Conference in Kansas City, Missouri, October 3–5, 1977

ISSN:0569-8197    

DOI:10.1080/05698197908982905

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor