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Phosphating mild steel causes the surface to be etched into a network of microscopic channels 0.0004 to 0.0008 in. deep, the phosphate crystals being located on the intervening high spots. With this type of surface, running‐in is both rapid and safe and low friction conditions are soon established. The phosphate crystals do not act as a solid lubricant in the same sense as graphite or M0S2; initial friction is higher and final friction is much lower. Friction of MoS2, for example decreases with rubbing by a factor of 4, from 0.2 to 0.05, whereas the friction of phosphated steel decreased by a factor of 60, from 0.3 to 0.005. In addition, the final friction of the run‐in phosphated surface depended on temperature and pressure in a manner characteristic of ‘thin film’ fluid lubrication, not ‘boundary’ or ‘solid’ lubrication.

The purpose of this paper is to test mechanical face seals made of carbon/SS316 with different coolants for evaluating its tribological performance. The reliability of a mechanical seal mainly depends on the seal materials and the type of coolant used for the lubrication.

Compressed air, vacuum and nitrogen are the main coolants utilized for the experimental work, and the obtained results are compared with the dry running case for a specified period. The experimental results are also validated with the computational fluid dynamics (CFD) simulation results.

The results shows that the sealing pressure, sliding speed and materials used would be the predominant factors for the seal design. Over compressed air, vacuum and nitrogen cooling techniques were found to be more efficient.

The experimental results are also validated with the CFD simulation results. This paper also emphasizes the usage of vacuum as a cooling medium in industries, which will enhance the seal life at an economical cost over nitrogen.

This paper aims to present a comparative study of a solar dryer with and without multiple phase change materials (PCMs). It also involves designing and fabricating the experimental model of an indirect solar dryer which uses PCMs for thermal energy storage.

A corrugated aluminium sheet is used as an absorber plate. Aluminium pipes of 0.75 inch are welded under the corrugated sheet to store the PCM. Here, multiple PCMs are used – one with a high melting point and the other with a low melting point for the purpose of improving efficiency. A single air pass model in which air moves over the absorber plate is used for the study. Air is heated in an air heater section which also contains thermal energy storage. The energy obtained in the air heater section is first used to heat and melt the PCM.

Thus, heat energy is stored into the PCM and then the heated air moves into the drying chamber in which drying take place. When the sun’s insolation reduces, discharging from the PCM takes place. Thus, it reduces the fluctuation in the energy and provides continuous energy to the system. Glass wool is used as an insulation material. Different parameters for this air heater-dryer have been calculated.

The current study enhances the understanding of solar drying process and the developed model with and without multiple phase change materials can be used for optimising the drying process.

THE PURPOSE of this contribution is to draw attention to a new development in the field of self lubricating bearing materials. A series of moulded products has been evolved, based on carbon and embodying various additives such as polytetrafluoroethylene and molybdenum disulphide, which improve the wear resisting characteristics of the products, particularly in conditions where normal lubricants fail or are inadmissible.

The pattern of food prosecutions in more recent times has remained relatively unchanged. Most have been taken under Section 2, Food and Drugs Act, 1955, even for foods which have obviously been unfit for human consumption. The Section because of its wider application has distinct procedural advantages. A few local authorities routinely use Section 8 successfully; it probably depends upon a more liberal interpretation and understanding by local justices. The five‐year study of food prosecutions, (BFJ 1971, 73, 39), separated them into a number of well‐defined groups and showed that those for the presence of foreign material were the majority and remained fairly constant throughout the period; mouldy foods increased during the five years and then remained steady as the second largest single group. The foods most commonly affected and the foreign matter commonly present could be seen; neither changed much during the period of the survey.

.Counter Competition. SUPERMARKETS and private shopkeepers battle for business in every High Street. In all shopping centres the private trader competes for the customer's cash with chain and departmental stores. He finds life increasingly difficult in face of rising overheads and shrinking profit margins.

The paper outlines the growth in low friction materials, the various elastomers available and the seal designs which have evolved around the utilisation of these materials.

Recently a water pipe burst in the ceiling above the technical services area of Memorial Library, Mankato State University. When our staff arrived for work, they found carts of books, audiovisual materials, and computer software soaked with dirty water which continued to drip from ceiling tiles onto work areas, desks, and new materials.