Showing papers in "Case Studies in Engineering Failure Analysis in 2017"

TL;DR: In this article, the authors investigated the causes of failure of the first stage gas turbine blade of 30MW gas turbine having tip cracks at the trailing as well as leading edge and further degradation of blade coating.

TL;DR: In this article, the authors investigated a first stage turbine blade failure in a 6.5MW gas turbine and found that overheating was the main reason of the blade failure, and the fracture surface exhibits the local melting occurred and re-solidified in the leading edge.

TL;DR: In this paper, a failure analysis of the boiler water-wall tube is presented in order to examine the causes of failure using various techniques including visual inspection, chemical analysis, optical microscopy, scanning electron microscopy and energy dispersive spectroscopy.

TL;DR: In this paper, the main cause of failure of AISI 347 stabilized stainless steel pipe after 60,000 of working in a petrochemical plant was investigated, and it was shown that the fatigue cracks formed at the outer surface of the investigated pipe, and were grown towards the inner surface at the fusion line of welded area.

TL;DR: In this article, the cause of failure of two adjacent super heater tubes made of Cr-Mo steel of a coal-based 60 MW thermal power plant has been portrayed in present investigation.

TL;DR: In this article, a new reliability model by synchronous consideration of both minimal and perfect repair is presented and modeled to figure out the optimal inspection interval for steam turbine system which the rotor considered as soft component and filter as hard component.

TL;DR: In this paper, the authors used the sample entropy for condition monitoring of a rolling bearing for wind turbine transmission system in Lu Nan wind farm in China, which is an important and fragile component in the wind energy industry.

TL;DR: In this paper, the formation of the circumferential cracks in clutch housings made of die cast hyper-eutectics B390.0 Al-Si alloys are assessed through optical microscopy and scanning electron microscopy.

TL;DR: In this article, the failure analysis of a dissimilar weld in a heat exchanger has been conducted, where the circumferential weld joining the carbon steel shell to the duplex stainless steel tubesheet experienced partial cracking as H2S was being introduced into the exchanger.

TL;DR: In this paper, a detailed investigation of the failure of a secondary super heater tube in a 140MW thermal power plant was carried out to deduce the probable cause of failure, which was concluded that the tube had failed due to severe creep damage caused by high metal temperature.

TL;DR: In this article, a finite element analysis (FEA) on a reconfigurable vibrating screen (RVS) is carried out to determine whether the structure will perform as desired under extreme working conditions at the different configurations of 305mm,×-610mm, 305mm-×-1220mm, and 610mm-mm×−1220 mm.

TL;DR: In this paper, a leak was found to form at the bottom of the elbow of a horizontal pipe and the main cause of failure was investigated through conducting standard failure analysis including visual examination, chemical analysis, mechanical characterization, metallurgical examinations using optical microscopy in combination with scanning electron microscopy (SEM) equipped with energy dispersive X-ray (EDX) analysis and corrosion test using a threeelectrode potential technique.

TL;DR: In this paper, the structural susceptibility of a 400kV power transmission tower subjected to progressive collapse and methods of determining the critical areas of above mentioned structure are investigated using OpenSees program for numerical modeling and nonlinear dynamic analysis of the tower which considers the buckling possibility of compression members and the plasticity in the cross sections as well.

TL;DR: In this article, the authors investigated the reasons for the failure of a buried pipeline perforated during construction by a chemical composition analysis; a metallographic test; macromorphology observation; characterization of the corrosion products by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Xray diffraction; field medium characterization.

TL;DR: In this paper, Elsvier et al. presented an open access article available under a Creative Commons license, which can be accessed at the following link on the publisher's website: https://doiorg/101016/jcsefa201705002

TL;DR: In this paper, the failure analysis of a carbon steel roller shaft of a continuous pad steam machine used in textile industry is presented, the failure position was located at a stepped diameter and the failure was caused due to fatigue.

TL;DR: In this paper, a 321 stainless steel charge heater tube failed in a refinery unit processing heavy crude oil, which was found to have black oil/coke deposits on its external surfaces.

TL;DR: In this article, a 304 type stainless steel plate in an amine exchanger unit, used between absorption and stripper towers, was examined and micro and macro examinations were performed on the plate and solution was analyzed.

TL;DR: In this article, the effect of additional holes on transient thermal fatigue behavior of gas turbines casings containing hole edge cracks was investigated, and the results from the numerical predictions were compared with experimental data.

TL;DR: In this paper, the forced draft fan (FDF) blade in a 300 MW coal fired power plant that experienced catastrophic failure has been investigated, and it is concluded that the material of the blade is cast Al-Si alloy (A356.0) that fits the requirements for FDF blade application, the failure was due to the external particles collide to the leading edge of the blades causing erosion and notch.

TL;DR: In this paper, the failure analysis of an actual Balance Arms surface was carried out using Fractography and Non Destructive testing techniques to dig out the root cause of the failure, which revealed microscopic signatures categorically pointing towards post failure surface mechanical damage.

TL;DR: In this paper, a study on overheated pipe due to scale was performed and it was discovered that long term overheating due to scales both at the outside and in the inside of the tube hinders the smooth heat transfer process.

TL;DR: In this article, a case study regarding frequent forced outages in an oil-fired power generating station due to failure of fire resistant fluid (FRF) piping of material ASTM A-304 is presented.

TL;DR: In this paper, three possible failure modes of acetal plastic toilet water supply nuts were examined with stereo microscopy and scanning electron microscopy (SEM), and the failure modes were compared and contrasted to provide guidance in determination of cause.

TL;DR: In this paper, the causes that promote failure of the fasten system and subsequent ejection of the wheels of passenger pickup trucks used in open-pit mines are analyzed by means of scanning electron microscopy, optical microscopy analyses and hardness tests.