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To provide information on the distribution of oil deposition inside the pipe conducting oil mist used for lubricating purposes and to show resulting variations of oil/air ratio.

The model of an industrial pipeline has been assembled ranging more than 100 m away from the oil mist source, equipped with devices collecting oil deposited inside the pipes. Other tests were performed in stands constructed as parts of pipes coiled in helical form. Long time experiments with continuous oil mist flow enabled to achieve calculable results.

The quantitative results obtained in experimental investigation on the reduction of oil/air ratio in an oil mist header system show that considerable differences of the oil/air ratio may be observed in a typical long pipeline. Possible consequences of oil deficiency on lubrication of remote mechanisms are presented in the case study. Results of tests are shown in diagrams and tables. These results may be useful for correction of design calculations procedures.

Tests have been made on the basis of one kind of the oil atomized in typical condition and conveyed with steady flow through the piping of rather simple geometry. However, there are other factors affecting oil droplets deposition and the most influencing are probably: the flow velocity/pipe diameter factor, oil atomization characteristics and the geometry of the oil mist piping.

The research has shown dramatic decrease of oil content in the long distance systems that may result in poor lubrication of remote mechanisms or over lubrication of those located close to the oil mist generator. It should be taken on account in calculation of oil mist demand to particular lubrication points.

Presented tests have been carried in the scale and flow parameters very close to those applied in industry. Thus, the results are reliable and could be very useful both for designers and the practitioners of centralized oil mist systems.

The purpose of this paper is to investigate that if the lubrication system of a helicopter reducer is compromised, its gears and bearings will be at non-lubricating oil work state, which causes the reducer to be damaged in a very short time.

Various 2 per cent additives were injected and mixed with aeronautical oil to produce 45-min oil/mist lubrication and oil/air lubrication experiments performed upon aeronautical steel tribo-pairs.

The results show that the best anti-wear effect is produced by oil/air lubrication that contains 2 per cent T391. It consumes the least quantity of oil and produces the least wear width, the least rise in temperature and the best surface wear quality.

The technology of oil/air lubrication that contains an extreme-pressure and anti-wear additive is a feasible way to improve the operational ability of a helicopter transmission system that is out of oil.

The purpose of this paper is to evaluate the cooling ability of minimum quantity lubrication (MQL) cutting fluid.

An experimental system is devised to find the heat transfer coefficient of MQL under simulated reaming conditions. Cooling rate of the specimen is measured with an infrared camera. The effect of air pressure and oil volume on cooling rate is tested. Metal cutting tests are performed to evaluate the effect of heat transfer coefficient on workpiece temperature.

Convective heat transfer coefficient for MQL increases with increasing air pressure. Oil volume has an indeterminate effect on the heat transfer coefficient; however, it is a dominant factor for controlling temperature during reaming.

The results of the study can provide guidance to optimize the temperature controlling ability of MQL for production.

There is limited information available in literature regarding the heat transfer coefficient of metal working fluids, particularly for MQL. In particular, experiments designed to investigate the effect of air pressure and oil volume on the heat transfer coefficient of the mist have not been previously documented. This information may be used to improve the overall cooling ability of MQL mist, thus increasing its effectiveness at controlling tool wear and maintaining part quality. The other major contribution of this work is to separate the role of the cooling and lubrication for controlling temperature while reaming aluminum. Prior to this study, there has been relatively little research performed for the reaming metal cutting operation, and still less for reaming with MQL. The nature of how metal working fluids control temperature is not fully understood, and this work provides insight as to whether cooling or lubrication plays the dominant role for reaming.

The purpose of this paper is to improve the lubrication and remove as much as possible of the heat generated in the bearing assembly, embedded in the jet engine.

To determine the necessary values of the air pressure and oil amount, an experimental approach is used. For that purpose, a custom made test rig is developed.

Less amount of oil makes better lubrication conditions, reflected in the smaller temperature of the bearings. Concerning the air pressure, too high and too low air pressure deteriorates the lubrication parameters. An optimum value should be determined experimentally. The influence of oil amount is remarkably bigger than the influence of air pressure.

This experimental investigation provides an easy and fast way to improve the high-speed bearings lubrication parameters.

The permissible period during which a grease‐lubricated bearing may operate before requiring re‐lubrication depends on the speed of rotation, the bearing type and dimensions, and a certain number of other factors.

Introducing the Mobilmet 100 series of mineral oil based cutting fluids with long service life

THE OUTSTANDING DEVELOPMENT in the air‐compressor field in recent years, particularly from the point of view of lubrication, has been the introduction of the oil‐cooled rotary compressor.