Showing papers in "Engineering Failure Analysis in 2001"

TL;DR: The effects of hydrogen on various metals and the use of metal hydrides for hydrogen storage are discussed in this article, where the mechanisms of hydrogen embrittlement and hydrogen attack of ferritic steels are compared, common sources of hydrogen in metals processing and treatment identified, and mechanisms for hydrogen entry into a ferritic surface are discussed.

TL;DR: In this paper, a bi-axial load-notch strain approximation for proportional loading is proposed to estimate the fatigue life of a passenger car wheel during the cornering fatigue test under plane stress conditions.

TL;DR: In this paper, a finite element model (FEM) in two and three dimensions was applied to the study of stress-strain state and stress intensity factors for the basic configurations of compressor and turbine disks and their operational damage.

TL;DR: In this paper, a collection of pump shaft failures that have been encountered during the consulting activities at the University of the Witwatersrand and the Plant Infrastructure and Pipelines Centre at the Council for Scientific and Industrial Research (CSIR) are presented.

TL;DR: In this paper, a finite element model has been made of a spline coupling between a shaft and a sleeve, and the residual stress on the shaft surface is measured and the lives of induction hardened shafts with splines are fatigue tested.

TL;DR: In this paper, the effects of degradation and impaired quality on the rope's bending-over-Sheave (BoS) fatigue endurance were investigated, and it was shown that the bending over sheave fatigue endurance of rope is little influenced by degradation and impairment, which is primarily dependent on the ropes construction and diameter ratio of sheave to rope.

TL;DR: In this paper, cracks in the surface of a fixed die half resulting in imprints on AlSi9Cu3 alloy castings were analyzed and identified by the use of penetrants.

TL;DR: In this paper, a case of failure of a 17-4-PH impeller in a gas lifting service was reported, where the fluid entrained water with a high level of salinity.

TL;DR: In this article, a finite element analysis is used to investigate the size of exit edge chipping as related to the loading conditions and intrinsic flaws of materials, and a local remeshing algorithm is implemented to accommodate the curved crack trajectory in forming an exit edge chip based on the theory of fracture mechanics.

TL;DR: In this paper, the failure of a 1.5 m diameter prestressed concrete line for water supply was examined, where the water pressure opened a hole of 0.5m 2 in the pipe wall by breaking the concrete into fragments and by tensile severing of a number of coils of the wire winding.

TL;DR: In this paper, an examination of several cracked and uncracked second row blades of 50MW class combustion turbines has been conducted to identify the cause of failure, and it was shown that these failures have been caused by environment-assisted creep in a manner similar to stress corrosion.

TL;DR: Otegui et al. as discussed by the authors presented a paper on the work of Otegui and Luis Jose, which was published by the Instituto de Investigaciones en Ciencia y Tecnologia de Materiales.

TL;DR: In this article, the effect of varied thread manufacturing process type and sequence on the mechanical properties of AISI 4340 stud bolts, and a laboratory procedure for distinguishing between them was developed.

TL;DR: In this paper, the authors demonstrate conventional and reliability-based approaches to the collapse cause assessment in order to identify the effects of misinstalled bracket and H-beam members on the collapse of a steel truss bridge over the Han river in Korea.

TL;DR: In this article, a failed roof tube from a bagasse boiler showed transverse through-cracks and extensive pitting, which was typically an oxygen induced pitting and numerous fatigue cracks had started within these pits.

TL;DR: The failure of an AM 350 steel bellows, which was used in the control rod drive mechanism (CRDM) of the fast breeder test reactor (FBTR), was noticed during helium leak testing as mentioned in this paper.

TL;DR: In this paper, the authors present criteria for material selection and hardness of thread rolling dies, along with three case studies of specific failures that emphasise why excessive hardness in this type of die material was inadvisable.

TL;DR: In this paper, the failure of a cadmium EP 18 Ni 1800 MPa maraging steel tension bolt occurred at a sustained stress of about 40% of the ultimate tensile stress (UTS).

TL;DR: In this paper, the effect of thread dimensional conformance of fasteners on yield and tensile strength was investigated, and the results from tests that investigate the effect that thread dimensions have on the performance of fastener components.

TL;DR: In this article, a custom built, but robust, air abrasive center hole drilling facility was used to sample residual stresses in the tube to tube-sheet welds, of both conventional circumferential fillet welds of protruding tubes as well as recessed ‘J’ configuration type.

TL;DR: In this paper, a downhole plugging tool manufactured from a duplex stainless steel forging was reported to fail due to surface pinhole formation and cracking associated with a region of high plastic strain.

TL;DR: In this paper, it has been concluded that the failure of the studs was due to reverse temper embrittlement and the failure was delayed due to the presence of Mo and V. To reduce the tendency to this kind of failure, the following steps were recommended: (a) reduce the phosphorus content in the steel to a low level or reduce the grain size to about 10 μm

TL;DR: In this article, the failure analysis of an automobile valve spring which failed in service was performed using a scanning electron microscopy (SEM) at suitable magnifications, and the failure was due to non-metallic inclusions near the surface of the spring material.

TL;DR: In this paper, the effects of parameter variability on the T-stub behavior are analyzed using reliability techniques combined with non-linear analysis of structures, and simplified safety rules are derived from this probabilistic high-level approach.

TL;DR: In this paper, the effects of bismuth segregation and sigma phase precipitation as a result of high temperature pretest aging on creep crack growth properties were evaluated using CT-type specimens and the data derived were arranged according to the parameter C ∗.

TL;DR: In this article, the authors present the reasons for failure, justify the solution and give economic information about some of the repairs already made in the case of cast mild steel breakages in the cement industry.

TL;DR: In this paper, the fitness-for-service (FFS) assessment has been carried out for the pipeline by use of the fracture mechanics approach, which shows that the pipeline may leak before break under designed operating pressure, and the lack of fusion defects in the welds may propagate under the condition of fluctuating pressure.

TL;DR: In this article, a collection of pump impeller failures that have been encountered during the consulting activities at the University of the Witwatersrand and the Plant Infrastructure and Pipelines Centre at the Council for Scientific and Industrial Research are presented.

TL;DR: In this article, the failure analysis of a river water circulating pump from a nuclear power plant is presented, where the failed component was the upper shaft made of martensitic stainless steel.

TL;DR: In this paper, the authors used finite element alternating technique (FEAT) for an arbitrary number of interacting three dimensional cracks, which they refer to as the MSD FEAT algorithm, to evaluate whether compliance measurements are useful in assessing continuing airworthiness.