Failure of a subsea crude oil API 5L X52 steel pipeline which led to oil leakage has been reported to occur after 27 years in service. Some leaks were found to form at the bottom of the horizontal API 5L X52 steel pipeline near an elbow section which connected the pipeline to a riser.
A 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.
A 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.
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.
A paper published in « Case Studies in Engineering Failure Analysis« , available on sciencedirect.com.
Corrosion has always been a problem in the petroleum refining and the petrochemical operations. The equipment of ISOMAX unit, such as reactors, furnace tubes, valves, and pipelines are frequently performed at high temperatures and high pressure condition. This working conditions, accelerates the failures due to corrosion. Therefore, heat- and corrosion-resistant alloys, e.g., austenitic stainless steels, have been widely used in this unit because of their excellent corrosion resistance, mechanical strength and toughness.
This paper describes failure analysis procedure of a cracked high pressure 321 SS RTJ flange in ISOMAX unit. In order to get conclusions related to crack propagation mechanisms of the flange, some investigations were done on the cracked flange that is mentioned in the body of the paper.
A paper published in « Case Studies in Engineering Failure Analysis« , available on sciencedirect.com.
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.
An interessant case study published in « Case Studies in Engineering Failure Analysis« , on 09january 2013.
A pinhole in elbow section of oil piping system is formed by localized corrosion. The corrosion is found to result from sequential chlorination and sulfidation reactions : the chlorination results from hydrolysis of calcium chloride in the crude oil and the sulfidation results from hydrogen sulfide in the crude oil.
Cet ouvrage du Cetim est un guide d’aide au choix des matériaux résistants à l’eau de mer.
Il synthétise les informations nécessaires pour sélectionner, en toute connaissance de cause, les solutions les mieux adaptées à la réalisation de pompes ou d’équipements pour des applications en milieu marin. Le guide est structuré selon une approche logique commençant par l’expertise d’une défaillance afin d’en déterminer la corrosion responsable ou par la prévision du type de corrosion susceptible d’apparaître en cours d’utilisation. Suivent la description des caractéristiques de l’eau de mer et des processus conduisant à la corrosion et une revue des différents matériaux utilisés en milieu marin: aciers non ou faiblement alliés, fontes, aciers inoxydables, alliages d’aluminium, de cuivre, de nickel et de titane. Le guide propose enfin quelques règles de conception et moyens de protection envisageables ainsi qu’une classification des matériaux vis-à-vis de leur résistance à la corrosion,au travers d’une série de fiches résumant leurs caractéristiques principales à prendre en compte.
Pour retrouver et commander cet ouvrage cliquez ici
A paper presented at the « International Conference on Processing of Materials, Mineral and Energy », 29th and 30th july 2016, PACE Institute of Technology & Sciences, India. It had been published by Elsevier.
This paper deals with the failure investigations of the first stage gas turbine blade of 30MW gas turbine. This blade is manufacture with of nickel based super alloy IN738. The main focus of the paper is to found the causes of failure of the blade. By the investigations, it is found that the blade failure takes place due to the combined effect of erosion, oxidation, overheating, and hot corrosion.
More at : http://www.pmme.co.in/papers/EMT-087.pdf
An article published in the « International Journal of Engineering Science and Computing », June 2016.
This paper study failure observed in riveted joint in buses and give solution to overcome this failure. In this stress analysis, fatigue analysis of pop up (Blind) riveted joint and Solid riveted lap joints are studied and from that predict the maximum shear strength of riveted joint to resist shear failure and no. of cycles of riveted joints. Also study the behavior of stresses and fracture observed on the Riveted due to stresses. This study is done by CAD software CATIA V5, CAE software Abaqus and correlate with analytical solution.
