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LUBRICATION, as a natural phenomenon is as ageless as time, its contribution, in early beginnings, to the formation of the terrain on which we live cannot be questioned; it was invaluable, in later times, following the glacial eras, indeed there is still no demonstration of the defeat of friction between two surfaces in close contact to surpass that of wet ice sliding over wet ice.

THE Minister of Technology has stated that savings could be made by British Industry to the tune of £500 million a year if the basic tribological principles were implemented. At last, the ethics of the medical profession that “Prevention is better than cure” is being adopted by industry through the medium of Planned Lubrication Maintenance.

HER Majesty The Queen, accompanied by H.R.H. The Duke of Edinburgh, officially opened the Spencer Works of Richard Thomas and Baldwins Ltd., near to Newport, Mon., on October 26th. The remarkable story of how this, Britain's newest Steelworks, has risen in less than three years from the marshland of Monmouthshire to become the most technically advanced iron and steel plant in the world has been told in the national and international press and many technical journals—and will continue to be told. We are concerned here with details of the lubrication equipment which plays such a vital part in ensuring continuity of production without breakdowns, but a few of the important facts and figures about this new plant will serve to refresh readers memories and to emphasise the important role that lubrication has to play.

A reciprocating sliding pad on plate boundary lubrication friction test is described. Typical friction waveforms are shown and compared with the output from an automated measuring system based on a digital storage oscilloscope.

The purpose of this paper is to develop a maintenance decision support system (DSS) framework using in-service lubricant data for fault diagnosis. The DSS reveals embedded patterns in the data (knowledge discovery) and automatically quantifies the influence of lubricant parameters on the unhealthy state of the machine using alternative classifiers. The classifiers are compared for robustness from which decision-makers select an appropriate classifier given a specific lubricant data set.

The DSS embeds a framework integrating cluster and principal component analysis, for feature extraction, and eight classifiers among them extreme gradient boosting (XGB), random forest (RF), decision trees (DT) and logistic regression (LR). A qualitative and quantitative criterion is developed in conjunction with practitioners for comparing the classifier models.

The results show the importance of embedded knowledge, explored via a knowledge discovery approach. Moreover, the efficacy of the embedded knowledge on maintenance DSS is emphasized. Importantly, the proposed framework is demonstrated as plausible for decision support due to its high accuracy and consideration of practitioners needs.

The proposed framework will potentially assist maintenance managers in accurately exploiting lubricant data for maintenance DSS, while offering insights with reduced time and errors.

Advances in lubricant-based intelligent approach for fault diagnosis is seldom utilized in practice, however, may be incorporated in the information management systems offering high predictive accuracy. The classification models' comparison approach, will inevitably assist the industry in selecting amongst divergent models' for DSS.

Looks at the use of lubrication in the maintenance of mining equipment through the examination of five case studies of mines from different areas and their consumption of lube oil. Concludes that a suitable management of lubricant consumption plays an important role in production costs and optimization.

LONG before man learnt to make fire by the friction of wood, he experienced the burden of friction in dragging home his kill. Perhaps it is not too fanciful to suppose that the torn sides of his beast gave the first solid lubricant. Blood and mutton fat were seriously recommended as lubricants for church bell trunnions as recently as the 17th century. Indoed we still reckon fatty acids the best of all boundary lubricants. The range of man's activities has increased enormously in the present century, and particularly in the last few decades. Men have circled the earth in space; a space ship is on its way to examine another planet; terrestrial man is boring to the bottom of the earth's crust; others have descended to the depths of the ocean, and oven established a home on the floor of the Mediterranean, Speeds have increased by factors of thousands, temperatures range from near absolute zero to thousands of degrees; and a new environment of high‐intensity nuclear radiation has been created. Still, objects must move over and along each other in these exotic conditions; and to a large extent solid lubricants can provide the answer to the frictional problems.

MUCH HAS been written over recent years about the technique involved in, and advantages to be gained from, centralised aerosol lubrication systems for bearings, gears and chains, etc., but not as much attention has been paid to the development of lubricating oils ideally suited for such systems. Some lubricant suppliers are of the opinion that the lubricant supplied should be formulated, taking into consideration only that it will adequately lubricate under the prescribed working conditions, and that the method of application should be made to suit it. This is rather an old fashioned approach, since with the advance of technology new innovations must be adopted, and provided that modifications to the lubricant do not adversely affect its lubricating properties, they should be made. To do this requires an appreciation of the dispensing equipment and necessitates liason between equipment manufacturers and lubricant producers to overcome difficulties, to the ultimate benefit of the consumer.

The purpose of this paper is comparison of experimental values of the drawing forces to numerical values in different contact conditions, taking into account the appearance of galling which occurs due to of difficult drawing process conditions.

The following two research approaches are used in this paper – the physical modeling, realized by the laboratory experiment, and the numerical simulation of the ironing drawing process. By analyzing the obtained results, the technique of physical modeling, with help of the laboratory equipment and numerical simulation by application of the finite element method, can be successfully used in studying the thin sheet ironing – strip drawing process.

It is significant to compare values of the deformation forces obtained by physical experiment to values obtained by the numerical simulation. In that way, it is possible to compare applied contact conditions (four lubricants in that case) and estimate matching of experimentally and numerically obtained results of the deformation forces. Presented results point out very good technological characteristics of ecologically friendly lubricant (single-bath) and grease based on MoS2. Significant decrease of the deformation force was achieved by its application, as well as maintaining of the lubricant’s layer during the forming process and almost complete elimination of galling on the contact.

Numerical analysis of stresses in the working piece wall, during the thin sheet strip drawing, requires precise values of the friction coefficient. It is an important indicator because one can define the contact conditions as the input data for the numerical simulation, based on its values for each type of lubricants and each value of the compressive lateral force.

The environmentally friendly lubricant tested exhibits a more favorable distribution of the drawing force during the process, mainly in experimental case. Grease based on MoS2 has good lubricating properties but that lubricant is conventional and environmentally unacceptable. Ecologically friendly lubricant can be successfully used in real ironing strip drawing process especially for high values of holding force achieving an increased tool life.

In translated form this paper is slightly shorter than the German original but I believe, nevertheless, that it retains all major facets which the author has painstakingly set out for the edification and interest of engineers and operatives who have any practical dealings with big gear drives of the open‐girth type. Herr Wollhofen draws skillfully on his expertise as Senior Engineer of Lubrication Engineering Headquarters of Klüber Lubrication München KG, and on his experience of special grease blending for girth‐gear installations in the hostile environment inseparable from cement kiln plant and mills where application of lubricants is by the adhesive spray system. We endorse his repeated emphasis on the fact that, to ensure best performance from such machinery and equipment, there is onus not only on the grease manufacturer to perfect his product, and on the service personnel to do their jobs properly, but also on the installer of the plant and its manufacturer and designer. The author's powerful plea that there must be better and closer liaison and co‐operation between all these factions may seem like crying for the moon. But when the resultant saving in time lost on repairs, and possibly capital outlay on premature replacements, is totted up, it is seen that Wollhofen's commonsense thesis has much to commend it.