A paper published in the « Indian Journal of Science and Technology« , august 2016.
A bellows expansion joint is an assembly of two or more bellows which help to tackle expansion or contraction in the system where it is designed to fit in. It was found, various independent researchers did lot of research in the design and geometry of bellows expansion joint but a review of all is scare, they have put forth the different possible features of bellows design in this paper. (…)
An article published in the « International Journal of Ethics in Engineering & Management Education » of july 2015.
Compress blade fails under several factors like high cycle fatigue, due to high rotational velocity, corrosiveness area, due to impinging foreign particle on compressor blade and also hard landing. This paper presents the failure analysis of compressor blade of helicopter engine.
A case study published in « Case Studies in Engineering Failure Analysis » – april 2016.
This paper investigates the failure of a rocker arm shaft of a passenger car. The shaft failed by brittle fracture across one of the four holes supporting the shaft into the cylinder head. The running distance of the engine just before failure was 40,626 km. These cracks may have been induced in the shaft by the non-uniform cooling during quenching in the course of heat treatment, or may be nucleated by repeated loading during service. This premature failure has occurred by the rapid crack propagation because of the lower fracture toughness of the martensite.
A paper find on the web about fatigue of Tidal Turbine Blade Composite Materials.
This has led to the emergence of tidal turbine designs often inspired from earlier developments in the wind turbine industry. Composite materials including Glass fibre reinforced polymers (GFRP) are a low-cost, low weight and corrosion resistant material for this application. Cyclic loading due to tidal flow and wave conditions is a common characteristic of tidal turbine devices and the good fatigue performance of composite materials means they are widely used, however limited information are available to predict material behaviour under coupled environmental and cyclic loading. This problem is addressed in this paper, by introducing a methodology for prediction of the fatigue behaviour of composite tidal turbine blades.
An article in progress in « Case Studies in Engineering Failure Analysis », Volume 7 (october 2016).
In this work, fracture failure of a shell-tube heat exchanger at the tube-to-tubesheet welded joints was investigated. Fatigue started at initial defects of the welded joint was confirmed as the failure mechanism of the heat exchanger. Bad welding and unsuitable expansion gave rise to the formation of initial cracks. The alternating stress comes from various reasons such as the resonant vibration.
An article in progress in « Case Studies in Engineering Failure Analysis », Volume 7 (october 2016).
This paper presents the results of a failure analysis investigation conducted in a connecting rod from a diesel engine (18 V, four-stroke) used in the generation of electrical energy. The continuous output of the engine was 10.5 MW, at 600 rpm ; before the failure of the con-rod it accumulated 35836 service hours, working with a load factor of 80%.
An article in progress in « Case Studies in Engineering Failure Analysis », Volume 7 (october 2016).
The formula SAE is a competition among students worldwide, where they are challenged to design, build and test a small formula-type racing car, following rules and specifications defined by the Society of Automotive Engineers (SAE). In the present analysis, a premature failure of a half-shaft of the transmission system of a racing car occurred after circa 100 km of use. The results show that the alloy steel bar used for the half-shaft did not follow specifications, with a consequent lower strength and resulting in a material with insufficient loading capacity and fatigue resistance. As a consequence, the fracture process was a confluence of torsional fatigue crack propagation and overload ductile fracture through the spline section of the half-shaft.
An article published in International Research Journal of Engineering and Technology (IRJET), Volume: 03 Issue: 04 | Apr-2016.
An analytical study was performed about piston failure by fatigue. Fatigue cracks are initiated and propagated by the action of mechanical and high temperature loading conditions which induces cyclic stresses in the piston material. Various proposals and solutions are presented so that necessary care can be taken to prevent piston failure in future.
An other case study published in « Case Studies in Engineering Failure Analysis« , october 2015.
This paper mainly investigates the fracture problem of U71Mn rail flash-butt welding joint. The analysis results show that the welding joint is fatigue fracture, and the fracture surface morphology is the cleavage fracture characteristics.
Source : Fracture analysis of U71Mn rail flash-butt welding joint
Trois cas d’analyses de défaillances survenues en service : hélices de navires et pale de ventilateur. Ces trois fiches d’analyse de défaillance avaient été publiées en 1984 dans la revue Cetim-information. Des dizaines de milliers de cas ont été traités ces quarante dernières années par le Cetim. Cette expérience fait du Centre une référence dans le domaine à même d’intervenir dans tous les secteurs d’activités. Avec aujourd’hui ses centres associés et partenaires, l’Institut technologique Cetim met un ensemble de compétences et de moyens au service des industriels et experts pour analyser, comprendre et proposer des solutions permettant d’éviter la reproduction de ces défaillances. Les différentes expertises de cette série « Cas concrets » sont issues d’articles publiés dans la revue Cetim Informations dans les années 74 à 90. Bien que ces fiches traitant de cas concrets soient anciennes, leur contenu est toujours d’actualité…
