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The purpose of this study was to solve the problem of most woven-fabric self-lubricating bearings that find it difficult to function at temperatures above 320°C, by designing a new type of new nuclear joint bearing. The results of this study will help designers to achieve accurate stress distribution, displacement deformation, fatigue life and damage of bearings. All of these can be a guide for designing self-lubricating joint bearings.

Finite element analysis is undertaken to simulate the new design bearings. To get the most appropriate and accurate results, the room temperature simulation (Simulation A), the modulus of elasticity that changes with temperature (Simulation B) and the thermal-structure-coupled simulation (Simulation C) are compared. The fatigue simulation is conducted to verify whether the self-lubricating method is reasonable and whether the bearing can function for over 60 years in an enclosed environment.

Stress distribution and displacement deformation of joint bearing can be accurately achieved via the thermal-structure coupled simulation. Work life and damage results have been achieved via the fatigue analysis, and the suggested working loads can be calculated via safety factors.

The newly designed joint bearing in which the graphite is laid on the outside of the inner ring functions and self-lubricates at temperatures above 320°C.

The fabric self-lubricating liners are the key factors impacting the performances of self-lubricating spherical plain bearings. The purpose of this paper is to improve the friction and wear properties of self-lubricating radial spherical plain bearings by modification of the liners.

The liners of hybrid woven PTFE/Kevlar fabrics were treated respectively by the LaCl₃ and CeO₂ solutions. The tribological properties of self-lubricating spherical plain bearings with treated or untreated liners under continuous swaying conditions were investigated with the bearing tester at the swaying frequency of 2.5 Hz and the swaying angle of ±10°. The film formation and wear mechanisms were analyzed based on the observation of worn surfaces with a scanning electron microscope (SEM) and an energy dispersive spectrometer (EDS).

Results show that the tribological properties of the bearings treated by the LaCl₃ or CeO₂ solution were improved compared with those of the untreated bearings. In particular, the wear resistance of bearings treated by the CeO₂ solution was remarkably improved under higher swaying cycles, but the anti-friction properties and cooling effects of bearings treated by the LaCl₃ solution were better under lower swaying cycles. Through SEM analysis, the reasons were analyzed. The bearings with treated liners only produced slight adhesive and abrasive wear, but the bearings with untreated liners produced more serious adhesive and abrasive wear under higher swaying cycles.

The paper proposed a new pretreatment process for the self-lubricating liners. The investigation on the friction and wear behaviors of the bearings is beneficial for prolonging the service lives of the radial spherical plain bearings.

Dr D. C. EVANS looks at some of the options open in selecting a plain‐bearing arrangement designed to operate where an external lubricant supply cannot be incorporated for reasons of environment or expediency.

PLAIN, slide‐surface bearings were used right at the start of engineering practice, in the form of simple bushes. Whereas there is nowadays a very wide selection of bearings of more sophisticated types, it is a fact that sliding surface bearings are still employed extensively in many modern and exacting applications. The forms have, however, changed drastically over the years, and no longer is the sliding‐surface bearing limited in application to supporting properly aligned shafts under conditions where lubricant can be directed in copious amounts to the friction surfaces. The modern counterpart of the simple bush can be of spherical‐seating type if required, for accommodating shaft misalignment, and may be manufactured from so‐called ‘self‐lubricating’ materials.

The purpose of this paper is to evaluate, by experimental investigation, the wear and friction performances of porous bearings under different operating conditions.

Two different compositions of self‐lubricating bearings were chosen: 90 percent Cu+10 percent Sn and 90 percent Cu+9 percent Sn+1 percent C. The bearings were produced with their final densities of 80 and 85 percent, and pressed at room temperature and high temperature.

The wear and friction properties of the sample bearings were determined at different running conditions such as temperature, applied load, and sliding speed. The variations of the weight loss with the sliding distance for different test conditions were presented. The results show that the weight loss and friction coefficient increase with the increasing sliding speed, density and temperature.

The wear and friction properties of the sample bearings were determined at different running conditions such as temperature, applied load, and sliding speed.

WHEN man invented the wheel, bearings were introduced into civilization and every machine since devised incorporates, in some form, means of sustaining a loaded member in motion by another fixed member. It is not surprising, therefore, that examination of bearings forms a high proportion of all engineering inspection and the phrase “to look at the bedding of the bearing” is probably one of the oldest in engineering practice. During recent years, particularly in the aircraft industry, developments have taken place in bearing design and bearing metals which require an inspection technique differing from conventional methods that served well when loadings were comparatively low and factors of safety high. Desirable clearances and surface condition of the earlier alloys will not answer at all well for some new bearing materials; while on the other hand defects such as minor cracks, which were very dangerous in white metal, have been proved by experience to have little or no effect on some heavily loaded lead bronze bearings.

LAMINATED material from which non‐metallic bearings and gears are fabricated may consist of fabric or paper treated with a synthetic resin. In producing this material, rolls of paper or fabric are fed in at one end of an impregnator which imparts a coating of the resin varnish. The impregnated material is dried and cut into suitably sized sheets, which are placed in layers to form a block of the material. The block is next pressed by hydraulic pressure under heat. This causes the resin to soften and flow so that the paper or fabric laminations merge under the pressure, which is round about one ton per sq. in. As heating is continued, however, the resin sets and can no longer be affected by heat; the laminations lose their separate identity and the material becomes a homogeneous mass. Another type of material much in use consists of asbestos—which may or may not be in the form of asbestos cloth—likewise impregnated with synthetic resin.

This paper aims to present the methodology to determine Archard’s wear coefficient. By applying this coefficient into the numerical simulation of wear, it is possible to predict wear without long lasting and usually expensive experiments.

To determine necessary particles of Archard’s equation and calculate wear coefficient K, an experimental investigation is proposed. Afterwards, the wear simulation is executed in FEM software ANSYS 18.1. Analytical method is offered to determine worn volume for cylinder-in-cylinder contact, based on “inclination” of inner cylinder.

Comparing the value of Archard’s coefficient obtained by this experimental investigation with the values from the literature for the similar materials, high correlation is noted. Furthermore, numerically calculated contact pressure is confirmed with analytical method. Trend of pressure decrease due to wearing process, as well as due to increase of contact surface is observed.

Since the prediction of the wear is closely related to the life cycle assessment of bearings, and the machines in general, it has significant practical importance for designers.

Determination of Archard’s coefficient is usually performed by conventional pin-on-disk tribometers. This methodology offers a different approach for the determination of Archard’s wear coefficient for cylinder-in-cylinder contact, which is convenient for shaft-sliding bearing contact.

ON January 10th last, President Nasser switched on the first of seven main and two auxiliary turbines of the hydro‐electric installation on the existing Aswan Dam on the River Nile, which, altogether, will provide 1,860 kWh of electricity.

The growing demand of efficiency and economy has led to a dramatic increase of the operating speed of the journal bearing, with a higher temperature distribution. This paper aims to investigate the three-dimensional temperature distribution of journal bearings.

A thermo-hydrodynamic lubrication model of a journal bearing was established based on the full 3D CFD method. A two-sided wall was used to include the conjugate heat transfer effect. The temperature-dependent characteristics of lubrication and cavitation impact were also included. The simulation results well agreed with the experimental results. Based on this method, the three-dimensional temperature distribution was analyzed under different operating conditions.

The temperature distribution in the radial direction had a difference. An increase of speed and de-crease of inlet temperature promoted temperature differences in the higher temperature zone and the increasing temperature zone, respectively. However, the inlet pressure had less influence on these differences. The temperature distribution was basically the same at a lower bearing conductivity. As the conductivity increased, the radial temperature difference was increased.

The temperature distribution in the radial direction was found under different operating conditions, and the present research provides references to understand the three-dimensional temperature distribution of journal bearings.