scholarly journals A Case Report of a Metal Allergy Patient Whose Prosthesis was Identified Allergenic by Non-destructive Metal Element Analysis and a Dermatological Patch Test

2006 ◽  
Vol 50 (2) ◽  
pp. 276-279
Author(s):  
Atsushi Mine
2014 ◽  
Vol 658 ◽  
pp. 261-268
Author(s):  
Jean Louis Ntakpe ◽  
Gilbert Rainer Gillich ◽  
Florian Muntean ◽  
Zeno Iosif Praisach ◽  
Peter Lorenz

This paper presents a novel non-destructive method to locate and size damages in frame structures, performed by examining and interpreting changes in measured vibration response. The method bases on a relation, prior contrived by the authors, between the strain energy distribution in the structure for the transversal vibration modes and the modal changes (in terms of natural frequencies) due to damage. Using this relation a damage location indicator DLI was derived, which permits to locate cracks in spatial structures. In this paper an L-frame is considered for proving the applicability of this method. First the mathematical expressions for the modes shapes and their derivatives were determined and simulation result compared with that obtained by finite element analysis. Afterwards patterns characterizing damage locations were derived and compared with measurement results on the real structure; the DLI permitted accurate localization of any crack placed in the two structural elements.


Author(s):  
Chitaranjan Pany

This paper discusses the design criterion of a pressurant steel tank made of HSLA 15CDV6 and proof pressure test (PPT) as a non-destructive examination. An inverse Ramberg-Osgood relation is used to represent the stress-strain curve of the material. Elasto-plastic finite element analysis (FEA) has been carried out to examine the adequacy of the design. Experimental stress analysis has been carried out from the measured strains and found maximum effective stress is at LS joint (max. measured strain location). Strain obtained from FEA is compared reasonably well with the proof pressure test (PPT) data at most of the strain gauge locations except at one long-seam (LS) joint. So, to explain the causes of difference in strains near one LS, parametric studies have been performed in a 3D FEA with varying LS mismatch to find the correct mismatch as a reverse engineering problem. It is found that a mismatch value of 0.9 mm will give the required strain at PPT, which is measured only 0.4 mm. The failure pressure estimated through nonlinear FEA/analytical expressions found to meet the design.


2007 ◽  
Vol 16 (2) ◽  
pp. 096369350701600 ◽  
Author(s):  
Buket Okutan Baba ◽  
Ronald F. Gibson

The aim of this study is to report the effect of delamination on the vibration characteristics of composite sandwich beams. The natural frequencies and corresponding vibration modes of a free-free sandwich beam with delamination of various sizes and locations are predicted using a two-dimensional finite element analysis (FEA). The presence of delamination affects the stiffness of the delaminated beam and results in differences on the natural frequencies of the beam. Assessment of the differences light the way for the existence, size and location of the delaminated region and can be used for a non-destructive evaluation of the damage characteristics of the delaminated beams. Vibration tests are conducted on fully bonded sandwich beams with carbon/epoxy laminated composite faces and foam core to verify the finite element results. Agreement between predictions of the model and experimental observations is good.


Author(s):  
Ji-Sung Ahn ◽  
Jai-Dong Moon ◽  
Wonyang Kang ◽  
Hyeong-Min Lim ◽  
Seunghyeon Cho ◽  
...  

2015 ◽  
Vol 797 ◽  
pp. 334-344
Author(s):  
Michał Bardadyn ◽  
Marcelo Paredes ◽  
Mateusz Wrobel ◽  
Krystian Paradowski ◽  
Andrzej Zagórski ◽  
...  

In this paper a newly environmental friendly Non-Destructive Testing (NDT) method for underground oil and gas pipeline networks is proposed. A suitable equipment extracts small samples of material from installed buried pipes for mechanical testing. Numerical calculations using Finite Element Analysis (FEM) proves that decreasing wall-thickness pipes is safe for in-field operating conditions. Nevertheless, those locations from where samples are cut should be monitored. For instance by means of Acoustic Testing (AT) system. New way of placing sensors is proposed. Sensors are introduced inside the pipe so that any acoustic wave changes from surrounding medium can be measured. In this type of AT a straightforward procedure must be followed to install sensors on pipe. Therefore, there is no need to uncover tested areas with qualified personnel. The research showed that the signals recorded from internal sensors are comparable to those results extracted from external ones. The study also revealed lower vulnerability to acoustic interference of the sensor placed inside the pipeline.


Author(s):  
Naoya Tada ◽  
Masaki Kosaka

The use of a flange joint is a popular method to close the end of pipes or connect pipes in manufacturing industries. As the pipes are often subjected to vibrations and cyclic bending, fatigue cracking may occur at the welded part between the pipe and flange. It is therefore important to detect and monitor the cracking in this part to ensure safety of the whole piping system. The direct-current potential difference method (DC-PDM) is known as a suitable non-destructive technique to monitor the initiation and growth of cracks and it has been applied to cracks and wall thinning on the inner surface of pipes. In this study, finite element analyses were carried out to clarify the relationship between the size and location of cracks at the pipe-flange welded part and the potential difference. An evaluation method of circumferential crack length angle by DC-PDM was proposed.


2020 ◽  
Vol 8 (5) ◽  
pp. 358 ◽  
Author(s):  
Yusak Oktavianus ◽  
Massoud Sofi ◽  
Elisa Lumantarna ◽  
Gideon Kusuma ◽  
Colin Duffield

A precast reinforced concrete (RC) T-beam located in seaport Terminal Peti Kemas (TPS) Surabaya built in 1984 is used as a case study to test the accuracy of non-destructive test techniques against more traditional bridge evaluation tools. This bridge is mainly used to connect the berth in Lamong gulf and the port in Java Island for the logistic purposes. The bridge was retrofitted 26 years into its life by adding two strips of carbon fiber reinforced polymer (CFRP) due to excessive cracks observed in the beams. Non-destructive field measurements were compared against a detailed finite element analysis of the structure to predict the performance of the girder in terms of deflection and moment capacity before and after the retrofitting work. The analysis was also used to predict the long-term deflections of the structure due to creep, crack distribution, and the ultimate moment capacity of the individual girder. Moreover, the finite element analysis was used to predict the deflection behavior of the overall bridge due to vehicle loading. Good agreement was obtained between the field measurement and the analytical study. A new service life of the structure considering the corrosion and new vehicle demand is carried out based on field measurement using non-destructive testing. Not only are the specific results beneficial for the Indonesian port authority as the stakeholder to manage this structure, but the approach detailed also paves the way for more efficient evaluation of bridges more generally over their service life.


Proceedings ◽  
2018 ◽  
Vol 2 (10) ◽  
pp. 564
Author(s):  
Tyler C. Borgwardt

Paleontological samples are rare and non-renewable, which makes the study of their chemical or physical characteristics require non-destructive methods. Physical characteristics are routinely studied with non-destructive methods; however, chemical studies tend to require destructive methods unless samples are very small or only the surface compositions are of interest. One potential technique for non-destructive elemental analysis is photon activation analysis (PAA). PAA is a versatile, broad-spectrum, multi-element analysis tool with low sensitivities, capable of analyzing large samples without any alteration, preserving the physical characteristics. Recent work has applied PAA to fossils and their source matrices in an attempt to correlate provenance through trace element analysis. PAA was shown to be non-consumptive and able to identify 20+ elements in samples with sub-ppm sensitivities. From that work, several lessons were learned and the non-destructivity of the technique was better characterized. PAA doesn’t have one standardized methodology, as it varies depending on the sample type. As such, from the lessons learned from the previous research, a standard method of applying PAA non-destructively to paleontological samples has been developed and will be presented in the following paper.


Sign in / Sign up

Export Citation Format

Share Document