Machine Elements Volume 1A: Identifying and Solving Problems

This series of books has four volumes, each divided parts (A,B, C because of printing reasons). It is intended as extension of the standard books, used for the dimensioning of machine elements. It is attended to aspects which get more and more importance for components of modern machines. A concern is the application orientation, i.e. the practice relevance. For this the awareness of the problems is more important than the mere knowledge.Energy efficiency, protection of resources and environment result in higher loads/stresses, utilisation of material strength and reduction of weight. Correspondent the demands at the machine elements and its safety increase. This, the design/construction of the machine elements, is the task of the standard books. Anyway problems and failures during operation must be expected. Unknown, respectively disregarded operation loads/conditions and component properties show first with application specific operation experience. Hopefully in time in appropriate tests and proofs. To avoid in the future failures and to find remedies for problems of components which are already assembled or even in service, the sourcing/identification of the causes is essential. This is a step, which is not focus in the standard books for the design of machine elements. This shall be complemented with this book-series. The literature about failure analysis is especially oriented at materials. Thereby prior-ranking are investigation methods, its analysis and case studies. So an assessment of the failure mode and the correlation to the failure mechanism takes place. However, this are only partly aspects of a systematic problem/failure analysis. It is merely a matter of a so called collection of facts, belonging a multitude of further fields like operation data and atmosphere as well a chronological sequences. Here the designer and the practitioner are needed. They demand in cases of a extensive problem clarification also laboratory investigations. Based on the causes of clarified problems and failures is the experience and with this the awareness of problems. This again requires experience. Helpful is a systematic problem analysis. Therein the determination of the facts, the development of the hypothesis and as last step the review of the hypothesis on the basis of the facts.To identify and the correct interpretation of first signs of a failure should be aspired. This can only be realized at the right area/position of the component. For this the knowledge of the failure mechanisms and the failure modes of the concerned machine elements is required. So weak points respectively faults of the design can be identified. The application specific know how and know why increases, this is an important competitive advantage.Against the assumption, the computer and calculation programs available today, would guarantee already the safety of the machine elements concerning operation problems, rather the opposite can be observed. The point is firstly, to identify all relevant effects. For this summaries of typical concerned components shall serve. Rising requirements respectively reduced safety distances demand the consideration of effects, which are hardly accessible a calculation. Because of this these and its mechanisms have been especially emphasized. Typical are production specific faults and weak points as well as operation influences in the form of wear, corrosion and aging. Combinations further aggravate the task. A calculation can be only as good, as it is component specific, lifetime and safety relevant. So the operation realistic testing often will be essential. For this, which detracts the calculation applies: „The engine will tell us“. Here, the understanding of this „language“ of a machine should be promoted. But keep also always in mind, if the machine „remains silent“, the possibility of an outage may be dangerously near if there have been changes to increase the performance or if there have been repairs.

The author Axel Rossmann was born 1939 in Berlin. He studied engineering at the Oskar-von-Miller-Polytechnikum and was employed 1965 till 2004 at MTU-München as failure/problem analyst. To his area of responsibllity belonged the investigation of civil and military aero engines and gas turbines in industrial use. These activities took place in line with development, series, production and assembling. About in ca. 40 years gathered experience, Axel Rossmann wrote several technical books.