Fatigue Failure Analysis of Rim

thikf9m1kxA new article published in the « International Research Journal of Engineering and Technology« , Aug-2016.

A Finite Element Method methodology is proposed for fatigue life and failure prediction of automotive steel wheel by the simulations of dynamic radial fatigue test (RFT). A short review of theoretical models, numerical simulation models were described in conjunction with bilinear elasto-plastic finite element stress analysis under wheel rotating loading.

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Publicités

Failure of high-chromium iron roll in compact strip production MILL

2016-12-08_11h16_13A case study published in « Case Studies in Engineering Failure Analysis« , july 2013.

A high chromium (HiCr) iron work roll broke in three pieces in finishing stand 4 in a compact strip production (CSP) mill of a steel company. The paper describes the causes of the roll failure manufactured from high chrome grade steel along with the precautionary measure.

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Investigation of turbine blade failure in a thermal power plant

1-s2-0-s2213290213000333-gr2A paper published in « Case Studies in Engineering Failure Analysis« , july 2013

The present work reports an investigation of a failure in a blade in the LP stage of a thermal power plant of 310 MW. After opening the turbine casing, one blade in the LP region was found fractured. The main damage occurred in the blade row 36 which is the L-3 row of the flow in the turbine side. The key objective of this paper was to identify the root of the failure.

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An investigation on the corrosion of flue gas sensor in boiler stack

2016-12-08_11h01_42A  paper published in « Case Studies in Engineering Failure Analysis« , July 2013

A commercial gas velocity sensor used for flue gases monitoring was subject to severe corrosion failure. An investigation was conducted based on visual inspection, microstructural study and SEM observation coupled to EDX analysis. A combination of mechanisms was proposed including a dominating severe dew point corrosion for both transducer and its covering, galvanic attack and an eventual hydrogen attack for the transducer side part. Recommendations were proposed to avoid a future severe damage to such type of sensor including an insulation between transducer and covering metals and an up-grade of the titanium alloy used.

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Cas Concrets-Arbres : ruptures brutales ou par fatigue

Avatar Cas ConcretsArbres de transmission de couples ou axes de rotation, voici trois cas concrets de ruptures d’arbres ayant des origines différentes : problème de matière, d’usinage, de sollicitations anormales.

Ces trois fiches d’analyse de défaillance avaient été publiées en 1979 dans Cetim-information.

Pour lire la fiche : Cliquez ici.

Cas Concrets – Ruptures de ressorts de soupapes

Avatar Cas ConcretsLes ressorts sont présents  dans de nombreux équipements mécaniques. Trois fiches d’analyse de défaillance illustrent trois modes de ruptures différents pour une même application de ce type de pièce.

Le Cetim poursuit la ré-édition des fiches d’analyse de cas concrets qu’il a publié dans la revue Cetim-Informations dans les années 74 à 90. Bien que qu’anciennes, le contenu de ces fiches est toujours d’actualité.

Pour lire la fiche : cliquez ici

Lamecanique.com : toute l’information mécanique en temps réel

De l’analyse des défaillances au développement durable en passant par la fabrication mécanique et la ré-industrialisation… rien ne manque dans ce vade-mecum disponible à tout instant, urbi et orbi. Présenté dans une forme agréable à lire, le portail concocté par le Centre technique des industries mécaniques (Cetim) et la Fédération des industries mécaniques (FIM) rassemble toutes les sources multimédia de ce domaine qui fourmillent d’informations aussi bien économiques que techniques.

Pour accéder au site : Lamecanique.com

Vintage-La rupture en service des assemblages vissés

Vintage assemblages vissesLes experts en analyse de défaillances du Cetim ont réalisé courant 1988 une étude statistique de 139 cas de ruptures d’assemblages vissés. Les résultats ont montré que pour les deux tiers des cas traités, 53 % des cas de rupture est dû à un phénomène de fissuration progressive et 47 % correspond à des ruptures brutales. Pour le tiers restant, plusieurs causes  conjuguées étaient à l’origine des défaillances.

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Failure analysis of Rocker liner used as a charging system of blast furnace

2016-12-08_10h04_01      2016-12-08_10h05_28

An article published in « Case Studies in Engineering Failure Analysis« , July 2013.

In this study, failure analysis of rocker liners used for charging system of blast furnace was carried out. The failed rocker liner samples shows non-uniform distribution of carbides, resulted in variation of hardness as well as wear properties. In the case of failed sample, the reason for the poor wear resistance of the component was due to the non-uniform carbide in pearlitic matrix.

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Sulfide stress corrosion cracking and hydrogen induced cracking

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A case study published in « Case Studies in Engineering Failure Analysis » on www.sciencedirect.com.

The wellhead flow control valve bodies which are the focal point of this failure case study were installed in some of the upstream facilities of Khangiran’s sour gas wells. These valve bodies have been operating satisfactorily for 3 years in wet H2S environment before some pits and cracks were detected in all of them during the periodical technical inspections. During investigation many cracks were observed on the inner surface of the valve body grown from the surface pits. The results indicate that flow control valve body failed due to combination of hydrogen induced corrosion cracking (HICC) and sulfide stress corrosion cracking (SSCC). According to HIC and SSC laboratory tests and also with regard to cost of engineering materials, it was evident that the best alternative for the valve body alloy is A217-WC9 cast Cr–Mo steel.

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