摘要:

A variational approach has been employed to solve Reynolds' equation for a finite length partial journal bearing. The pressure, is obtained as a doubly infinite sine series and the load capacity can be expressed, for some bearings, as a simple sum of coefficients. Applications include a 60 degree, L/D = 0.5 partial are bearing and a L/D = 1.5 plain journal bearing for which both the half Sommerfeld and Reynolds' boundary conditions are employed.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:10.1080/05698197908982906

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Stiffness and damping coefficients are presented for the 5-pad tilt-pad bearing for various preloads, offsets, length to diameter ratios and pad loadings (on and between pad). Finite elements and the pad assembly method are used to calculate these coefficients and the effects of the unloaded pads are included. Design curves suitable for tilt-pad bearings in widespread industrial use are presented.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:10.1080/05698197908982907

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Designs are needed for large, heavy duty tilting-pad thrust bearings to minimize the load and thermal distortions of sliding surfaces which adversely effect bearing performance. A new bearing construction is proposed in this paper, aimed at reducing thermal distortion. The effects of the thermal distortion on proposed design are analyzed with a simplified model and a significant improvement in bearing performance in comparison to a conventional bearing, is confirmed in tests.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:10.1080/05698197908982908

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Base fluid-metal interactions of a super-refined paraffinic mineral oil were studied. Wear debris from a Shell Four-ball wear tester was analyzed. Based on the amount of iron distributed among used oil, organic solid, iron particles, and iron oxides, one is able to interpret the wear phenomenon in terms of mechanical and chemical processes. Oxygen concentration at the wear junction controls the type of the chemical interactions between the metal and the lubricant. These chemical reactions appear to be controlled by the thermal gradient at the junction; catalytic effects by the metal are insignificant.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:10.1080/05698197908982909

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

An investigation was conducted to examine the friction properties and mechanical behavior of single-crystal silicon carbide (0001) surface sliding against itself and against polycrystalline titanium. The results indicate hexagon-shaped pits of silicon carbide and the formation of platelet hexagon-shaped wear debris of silicon carbide due to cleavages of both prismatic and basal planes as a result of silicon carbide sliding against itself. The fracturing of silicon carbide also occurs near the adhesive bond to titanium. The wear debris produced by brittle fracture plows the titanium and transfers to it. Further, the silicon carbide wear debris, which adhered and transferred to titanium, plows the silicon carbide surface and transfers back to it.

ISSN:0569-8197    

DOI:10.1080/05698197908982910

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A study has been made of the action of a commercially available corrosion inhibitor added to hydrofined aviation fuels in reducing the wear of aluminum bronze sliding on KE180, 13 percent chromium steel.

ISSN:0569-8197    

DOI:10.1080/05698197908982911

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

The fluid film lubrication equation for a zero-speed, orifice-compensated, multipocket hydrostatic journal bearing is solved by a finite element method for determining its steady-state performance and the dynamic stiffness and damping coefficients. These coefficients of the film influence the response of the shaft-bearing system. Performance data have been computed for a four-pocket bearing of L/D = 1.0, with various orifice design parameters and eccentricity ratios. For stability studies, critical mass for the linearized system has been determined by Routh's criterion. By discretizing time and using the Runge-Kutta method, motion trajectories of the journal center have been theoretically determined for a small arbitrary initial disturbance.

ISSN:0569-8197    

DOI:10.1080/05698197908982912

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

A new basic bi-dimensional cutting test, which deals with the major concerns of cutting fluid users, was developed: it consists of a parting operation carried out at constant cutting speed, on a lathe equipped with a DC-driven spindle.

ISSN:0569-8197    

DOI:10.1080/05698197908982913

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Thrust bearing characteristics are examined in the motion generated by the accelerating slider. The selected case is the situation where the fluid within the lubricating film initially is at rest and at time zero the infinitely long slider assumes a velocity which is a function of time. Numerical solutions to the governing differential equations are obtained for the case of constant but arbitrary acceleration and for the case of acceleration proportional to time. The corresponding previously published analytical solutions are compared with those numerical results.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:10.1080/05698197908982914

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor

摘要:

Statistical theories of rough elastic contact have previously been developed for the contact of spheres and of parallel cylinders, and have predicted stress distributions significantly different from those of the classical Hertzian theory. The theories characterize the surface in terms of three surface parameters describing, respectively, the roughness, density and radius of curvature of the asperities. In this paper, a procedure is described for quantifying these theories by obtaining the surface parameters from the spectral-moment approach to surface description; the only surface measurement needed is one of roughness. The procedure is illustrated by two numerical examples relating to the contact of a rocker arm with a pushrod and to a journal bearing. In the case of the rocker and pushrod, no significant difference from the smooth-surface results is found. In the case of the journal bearing, however, the maximum stress is calculated to be 36 percent less, and the nominal contact width 2.2 times more, than the respective figures for smooth contact.

ISSN:0569-8197    

DOI:10.1080/05698197908982915

出版商:Taylor & Francis Group    

年代:1979

数据来源: Taylor