Water-lubricated bearings have attracted increasing attention in recent years because of their environmental sustainability, simplified design, low cost, good cooling performance and low coefficient of friction. To show the characteristic of water lubrication more clearly, this paper quantitatively compares the lubrication performances of water-lubrication plain journal bearing and oil-lubricated plain journal bearing using CFD method. Bearing length, friction coefficients, power losses and temperature rises are obtained under the same working condition. Results show that water-lubricated bearing needs to be 3.4 times longer than oil-lubricated bearing, but its friction coefficient and power loss are only 11.7% of those of oil-lubricated bearing and its maximum temperature rise is less than 2 K, much lower than 96.76 K corresponding to oil lubrication.

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In recent years, composite bearings are increasingly employed in marine and heavy load situations due to the specific properties of composites. However, for the tape winding composite bearings, the tension in process has not been studied in depth. In this study, a device was manufactured to apply tension to the process and the prepreg tape was T300/epoxy. Specimens with different tension values were selected for the experiment and the autoclave technology was applied to the curing process. Then, the appearance image and roundness of the bearing composites were acquired. Meanwhile, physical and mechanical properties of the specimen as well as the residual stress were measured. The experimental results show that the influence of tension in winding process on bearing composites is significant and the optimum tension can be defined. Subsequently, the article analyzes the function of the tension and it is concluded that the wrinkles and waves on the surface of the T300/epoxy bearing composites can be eliminated using proper method and the optimum tension should be determined through testing and experiment.

Although the extensive research has expanded on the modification of cyanate ester (CE) resins and the mechanical properties of CE composites, very few studies have been conducted on carbon fibre (CF)/modified CE winding composites and the thermomechanical properties of the composites. In this research, epoxy (EP)-modified novolac cyanate ester (NCE) and bismaleimide (BMI)-modified NCE resins were prepared. The CF/modified CE winding composites were manufactured, and their thermomechanical properties were tested. The optimal winding process was determined, and a preheating technique was implemented. Then, the EP/CE resin (10:90) and the BMI–DBA/CE resin (10:90) were selected as the resin matrix of the winding composite based on the viscosity properties, mechanical properties and thermal analysis (using thermogravimetric analysis and differential scanning calorimetry) of the modified CE resin. The selected resin exhibited good manufacturability at 70°C, good thermal stability and high Tg (above 370°C). The thermomechanical property tests indicate that the modified CE resin composite exhibits an outstanding mechanical strength at room temperature and at high temperatures (130°C, 150°C and 180°C) compared with that of the pure CE resin composite. The reasons for this enhancement can be attributed to a toughening mechanism and the effect of sizing agents on the CFs.