Showing papers in "Engineering Failure Analysis in 2007"

TL;DR: In this article, the performance of reinforced concrete buildings during recent earthquakes in Turkey is discussed and important general lessons learned from these earthquakes are formulated and a short overview of the emergency management measures taken is also presented.

TL;DR: In this article, the residual stress profiles in aluminum and steel welds, and in shot peened aluminium, obtained via synchrotron and neutron diffraction at the ESRF-ILL in Grenoble, were presented.

TL;DR: In this paper, the best practices for the assessment of corrosion in pipelines are presented, and the results of a joint industry project are documented in a simple and easy-to-use manual.

TL;DR: In this paper, the transversal cracking of a seamed API 5L X46 steel tube belonging to a crude oil pipeline was investigated, and the main cracking nucleated in the internal surface of the tube, at the boundary between the heat-affected zone (HAZ) and the weld metal, propagating in a stable mode along the radial and longitudinal directions.

TL;DR: In this paper, a transmission oil products API 5L X52 pipeline in northern part of Iran cracked, which led to oil leakage, and simultaneous effects of SCC and sulfate reducing bacteria (SRB) induced cracking were demonstrated.

TL;DR: A very good agreement of simulation and real crash tests results was observed, which justifies the use of computer simulations in the process of development and certification of road safety barriers.

TL;DR: In this paper, a case study of the Monastery of Jeronimos in Lisbon, Portugal is used for structural safety assessment, where a set of sophisticated non-linear failure analyses are performed and the consequences associated with the results obtained are discussed.

TL;DR: In this paper, a multidisciplinary approach to heritage documentation involving close range photogrammetry and ground penetrating radar techniques, as well as the development of finite elements based structural models is presented.

TL;DR: In this article, the authors present a number of case studies from their own work that collects the results of investigations on failed drillstrings and components spanning over a decade of activity in the North Sea.

TL;DR: In this article, the authors present results and conclusions arising from an investigation into a shrink-fit failure on a gear hub/shaft assembly, which formed one element of a full failure investigation and set out specifically to determine whether or not fretting or micro-slipping was the cause of failure.

TL;DR: In this article, the role of discontinuities in the microstructure and the relative contributions of each type of discontinuity was investigated in fatigue crack nucleation in an aircraft fuselage.

TL;DR: In this article, a finite element analysis was conducted to study dynamic elastic-plastic stress when a wheel passes a rail joint with height difference between the two sides of a gap.

TL;DR: In this paper, a case study of failure analysis of a 40MW gas turbine blade made of Udimet 500 is presented, where the cause of failure is found to be intergranular cracks which started during exposure to high temperature.

TL;DR: In this article, a stainless steel orthopaedic (femoral) implant was examined, which had fractured inside a patient's thigh, and different damages were observed such as crevice corrosion pitting, initiation of cracks from these pits, intergranular surface cracking inside the crevice, and SCC-like branched cracks.

TL;DR: In this article, fracture analysis of a universal joint yoke and a drive shaft of an automobile power transmission system are carried out for each part, and stress analysis is also carried out by the finite element method.

TL;DR: In this paper, the S-N curve for aluminum alloy (Al) A356 was developed by conducting tests at different stress levels under constant amplitude loading, and the prediction of fatigue life using finite element analysis (FEA) was found to be in close agreement with the corresponding experimental observations.

TL;DR: It is shown that initially, when data is acquired from a point machine, it is difficult to detect faults, however, upon the application of a moving average filter, fault conditions can be more straightforwardly detected and diagnosed.

TL;DR: In this article, a test methodology for determining the dynamic behavior of railway fastening setting pads in working conditions, which may involve a wide range of temperatures associated to the wear and the hardening they undergo during the cyclical load process applied on them caused by the passing of the trains, was presented.

TL;DR: In this article, a brief review of salient points relating to wear as a product failure mechanism is presented and illustrated by numerous studies from the authors' forensic casebooks, as well as a brief discussion of wear processes at play during the service lifetime of a system, device or component.

TL;DR: In this paper, the authors discuss some of the issues that may arise during the assessment of mechanical damage, such as: when is a feature really a dent; when does a superficial scrape become classified as a gouge; and the limitations of existing assessment methods.

TL;DR: In this paper, the failure of an 18-inch diameter electric resistance-welded gas pipeline was characterized as a stress corrosion failure that had initiated at a longitudinal "stress raiser".

TL;DR: In this article, the dynamic response of masonry stone buildings during the 2004 Dogubayazit (Agri) earthquake, where a large number of such buildings were heavily damaged or collapsed.

TL;DR: A failure case of the low pressure blades of steam turbine is presented in this paper, where the suction side of blades has been quenched to improve the erosion resistance Cracks with different lengths were found in the quenches region of final stage blades after about 13,200h service.

TL;DR: In this paper, the causes of in vivo fracture of a cementless hip prosthesis model manufactured with Ti6A14V alloy were investigated, and the results indicated that the fracture was initiated at the junction radius of the neck with the collared device, with around 90% of the fracture surface being due to a fatigue mechanism.

TL;DR: In this paper, an analysis was made on the failure and shut down of boiler cold and hot reheater tubes by chemical analysis of sediments, metallographic examinations, XRD, SEM and EDX studies.

TL;DR: In this article, the authors demonstrate different approaches towards MIC identification in three real cases of technological equipment failures, including the failure of a carbon steel heat exchanger as a result of tubes, lids, tube sheets, and connection pipes clogging.

TL;DR: In this paper, a case study on bank front tubes is presented, showing that the root cause of boiler tube failure were caustic and phosphate corrosion, due to availability of NaOH or of alkaline-producing salts.

TL;DR: In this paper, different methods of time signals analysis are presented, and significant changes in tooth stiffness are the result of a fatigue crack in a tooth root, which often leads to failure of gear unit operation.

TL;DR: In this article, the influence on the resistance to loosening of basic parameters such as preload, fastener material elastic modulus, nominal diameter, thread pitch, hole fit and lubrication is quantified.

TL;DR: The information gained during this analysis brought to the four that the principle mode of mechanical failure for acetabular cups is overheating of the UHMWPE, mainly due to a lack of good and/or sufficient lubrication.