Burst strength of glass fibre/epoxy composite pipes subjected to impact loading

An article discussed during the International Conference on Applications and Design in Mechanical Engineering 2015 (ICADME2015)

icadme2015

The main objective of this experimental study was to investigate the effects of low velocity impact loading on the pressure bearing capacity of the E-glass/epoxy composite pipes. The pipes were produced by the conventional filament winding technique comprises of six axisymmetric layers with (±55°)3 winding angles. The specimens were impacted at three different energy levels which are 5 J, 7.5 J, and 10 J using an instrumented drop weight impact testing machine (IMATEK IM10). The samples were then filled with water and subjected to burst test until distinct leakage failure is observed. The results indicate that the peak force and contact time increases with increased of impact energy. For impacted samples, the pressure tests show that the burst strength of the pipes decreases with increase in energy levels during impact loading. During the burst tests, several damage types named leakage and eruption were observed.

Read more

Failure investigations of a 900 KV bil trench cota bushing

A case study of failure discussed in the 82 nd International Conference of Doble Clients.

bushingThe discussion of this paper will focus on the H1 Trench COTA bushing, which failed after field maintenance handling that would not normally be expected to have a negative effect on a bushing. Following the failure, the top air side porcelain was found ruptured and missing; the bottom insulator was fractured into a number of pieces. The H2 and H3 bushings from this transformer, which were identical Trench type bushings, were also removed and disassembled for inspection to help identify a possible root cause of the H1 bushing failure.

More at : http://www.doble.com/content/show/boston2015/files/BIIT/BIIT-2_Trench_COTA_Failure_Root_Cause_Mani.pdf

 

Fatigue Failure of Aluminium Alloy Piston

An article published in International Research Journal of Engineering and Technology (IRJET), Volume: 03 Issue: 04 | Apr-2016.
pistonAn 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.

Read more

Catastrophic failure of a carbon steel storage tank due to internal corrosion

A case study of failure analysis published in « Case Studies in Engineering Failure Analysis« , october 2013.

Catastrophic failure of a 10 m high, 8 m diameter steel storage tank containing approximately 350 m3 of waste solvent led to a significant environmental incident in 2009. An investigation was carried out to establish the root cause and to learn lessons that might prevent a reoccurrence.

Read more

Failure analysis of a high strength low alloy steel pressure vessel

 

A Failure Analysis published in « Case Studies in Engineering Failure Analysis » october 2013.

High strength low alloy (HSLA) steel with a nominal composition of 0.15C–1.25Cr–1Mo–0.25V is being extensively used in space programme. Owing to its ease of fabrication and welding, a tank was fabricated out of this alloy. The tank is used to contain strontium per chlorate which on combustion develop secondary thrust, effectively used during attitude control of satellite launch vehicle. During one of the routine qualification tests, a tank had failed at an internal pressure of 109 bar, against a designed proof pressure of 120 bar.

Failure was initiated from long seam weld of a cylindrical shell and propagated into the parent material thereafter. Detailed metallurgical investigation has been carried out to understand the cause of failure. This paper brings out the detail of investigation carried out.

Read more

Adapter les dentures aux déformations

Suite aux pannes à répétition sur la ligne de propulsion d’un navire d’exploration pétrolière de la CGG, le Cetim en a identifié les causes et fourni les éléments pour y remédier en gardant le bateau en exploitation.

Lire l’article

Simulation vibratoire d’un banc d’essai géant

Pour réaliser la validation du comportement vibratoire de son banc d’essai pour les groupes motopompes primaires de centrales nucléaires qu’elle produit, Areva NP Jeumont a joué la carte de la simulation avec le Cetim. Lire le récit !

Lire l’article

Autoclaves industriels : contrôler sans démonter

Spécialisée dans la fabrication de moyens chauds pour la cuisson des composites, Aeroform confie au Cetim les opérations de requalification des autoclaves industriels afin de mieux équilibrer la charge de ses équipes.

Lire l’article

L’expertise de vannes de barrage passe les frontières.

2016-04-22_08h28_52Les nombreuses années d’expertises d’ouvrage pour le compte du producteur d’énergie électrique historique en France n’empêchent pas les experts du Cetim d’effectuer ce type de prestation à l’étranger. Exemple au Maroc. Leur mission : le diagnostic de l’état des cinq vannes de crue d’un barrage. L’opération s’est déroulée en deux étapes. D’abord, un contrôleur a passé cinq jours sur place pour réaliser l’ensemble des inspections et mesures nécessaires. Ensuite, l’ensemble de ces données a été exploité pour paramétrer le modèle des vannes de crue, afin de déterminer par simulation si elles supporteraient l’ensemble des sollicitations auxquelles elles peuvent être soumises. A noter, c’est la première fois que Tractebel Engineering, filiale d‘Engie, fait appel au Cetim pour profiter de sa double compétence dans le domaine du contrôle sur site et de la simulation par éléments finis.

Lire l’article