New support roller profile design for railway wheel re-profiling process by under-floor lathes with a single cutting tool.

The wheel re-profiling is an important part of railway wheelset maintenance. Researchers and railway operators have been very concerned about how to minimize the loss of time during wheel re-profiling without decreasing safety. Avoiding wheelset disassembly means considerable time savings, while reducing wheel damage during operation. Underfloor wheel lathes are the most appropriate tool to achieve this double objective, and therefore the most used nowadays. Multi-cut tool lathes have the disadvantage of being extremely expensive. On the other hand, with single tool lathes, re-profiling is not smooth or safe enough when current convex profile support rollers are used. It is well known by the companies that during reprofiling the wheel suffers impacts/damaged. In this article, a methodology to optimize the profile of the support rollers used in underfloor single tool lathes for railway wheel re-profiling is proposed. This novel profile design will minimize damage and increase the safety of such lathes, since it proposes a greater smoothness in the process. Simulations of re-profiling process have been carried out by the finite element method showing that the designed roller profile reduces drastically the impact/damage during the operation. The impact generated between the re-profiling wheel and the rollers is avoided. Profile-optimized support rollers have been used in a real underfloor wheel lathe, showing good results.

[The health situation of the non-institutionalized elderly urban population of Castro Uridiales and the differentiating characteristics of those attending the health center frequently]. / Situación sanitaria de la población anciana urbana no institucionalizada de Castro Urdiales, y características diferenciadoras de los que más frecuentan el centro de salud.

OBJECTIVES: Main: to describe the health situation of the urban non-institutionalised population of 75 or over in Castro Urdiales. Secondary. To analyse the differences in the over-user group. DESIGN: Descriptive, crossover. SETTING: Primary Care Health Centre. PATIENTS: People in the urban area aged 75 or over and with the following inclusion criteria: not institutionalised, who had been at least 6 months in the town, and for whom there was data for locating them. Over-users: people in the upper third of attendance (9 or more consultations per year). MEASUREMENTS AND MAIN RESULTS: A "Comprehensive Geriatric Assessment" was performed, cognitive state (Pfeiffer) and social assessment. The over-user group functioned better, had a better cognitive state and consumed more medication. CONCLUSIONS: The results coincided with other studies in most of the items analysed. It is important to be aware of the worse functional and cognitive condition of the group which attended the Health Centre least. Sub-groups of the elderly still need to be studied.