scholarly journals Failure analysis of performance vehicle mechanical gear

2018 ◽  
Vol 188 ◽  
pp. 04019 ◽  
Author(s):  
Antonios D. Tsolakis ◽  
Konstantinos I. Giannakopoulos ◽  
Andreas S. Gkertsos
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Failure Analysis ◽  
Dynamic Loading ◽  
Power Transmission ◽  
Working Environment ◽  
Commercial Vehicles ◽  
Machine Element ◽  
Analysis Of Performance

Gears are the main machine element in vehicle power transmission trains. In commercial vehicles, power transmission trains design complexity consists of the determination of the loading parameters which depends upon the working environment of the performance vehicle. In the present work a gear failure under dynamic loading is investigated. The failed gear is part of a 2 speed gearbox of a Rotax DD2 2-stroke Open- Wheel performance vehicle (go-cart type). The gearbox was in racing conditions when failure occurred. The vehicle was speeding in 2nd Gear at wide open throttle when instantaneously the driver by fault downshifted to 1st gear. The result was for the first gears break a whole piece and eventually the system to go out of operation. Chemical composition of the examined metallic components was determined via EDAX chemical analysis.

scholarly journals Failure Analysis of fractured Fixing Bolts of a Mobile Elevating Work Platform using Finite Element Methods

2019 ◽  
Author(s):  
DongHoon Choi ◽  
Jae-Hoon Kim
Keyword(s):  
Finite Element ◽  
Chemical Composition ◽  
Chemical Analysis ◽  
Failure Analysis ◽  
Visual Inspection ◽  
Standard Procedure ◽  
Fatigue Analysis ◽  
Certification Authority ◽  
Element Analysis ◽  
Safety Certification

Mobile elevating work platforms (MEWPs) consist of a work platform, extending structure, and chassis, and are used to move persons to working positions. MEWPs are useful but are composed of pieces of equipment, and accidents do occur owing to equipment defects. Among these defects, accidents caused by the fracture of bolts fixed to the extension structure and swing system are increasing. This paper presents a failure analysis of the fixing bolts of MEWP. Standard procedure for failure analysis was employed in this investigation. Visual inspection, chemical analysis, tensile strength measurement, and finite element analysis (FEA) were used to analyze the failure of the fixing bolts. Using this failure analysis approach, we found the root cause of failure and proposed a means for solving this type of failure in the future. First, the chemical composition of the fixing bolt is obtained by a spectroscopy chemical analysis method, which determined that the chemical composition matched the required standard. The tensile test showed that the tensile and yield strengths were within the required capacity. The stress analysis was carried out at five different boom angles, and it was determined that the fixing bolt of MEWP can withstand the loads at all the boom angles. The outcomes of the fatigue analysis revealed that the fixing bolt fails before reaching the design requirements. The results of the fatigue analysis showed primarily that the failure of the fixing bolt was due to fatigue. A visual inspection of the fractured section of the fixing bolt also confirmed the fatigue failure. We propose a method to prevent failure of the fixing bolt of the MEWP from four different standpoints: the manufacturer, safety certification authority, safety inspection agency, and owner.

The Choice of Chemical Composition and Raw Materials for the Production of Basalt Wool with the Defined Characteristics

2018 ◽  
Vol 284 ◽  
pp. 1018-1023
Author(s):  
A.V. Khandoshka ◽  
Svetlana G. Vlasova
Keyword(s):  
Surface Tension ◽  
Chemical Composition ◽  
Chemical Analysis ◽  
Thermal Insulation ◽  
Raw Materials ◽  
Mineral Wool ◽  
Chemical Compositions ◽  
Insulation Material ◽  
X Ray

The composition of mineral wool was selected for the research, based on the chemical composition of the raw materials, the determination of the acidity module to obtain the thermal insulation material with the best characteristics and the lowest cost of the production of basalt mineral wool. The paper deals with compositions of raw materials and selection chemical compositions of charges for production of basalt mineral wool, and the experiments of welded samples were made and tested for viscosity, surface tension, chemical analysis and x-ray analysis.

The crystal-structure and optical properties of matlockite (PbFCl)

1934 ◽  
Vol 23 (146) ◽  
pp. 587-597 ◽  
Author(s):  
F. A. Bannister
Keyword(s):  
Crystal Structure ◽  
Optical Properties ◽  
Chemical Composition ◽  
Chemical Analysis ◽  
Single Crystal ◽  
British Museum ◽  
Museum Collection ◽  
X Ray ◽  
Fluorine Determination

It has recently been shown by W. Nieuwenkamp that matlockite is identical in chemical composition and crystal-structure with artificial lead fluochloride PbFC1. His conclusion is based upon powder photographs of the two substances and a fluorine determination of a specimen of matlockite from Matlock, Derbyshire. The present work was undertaken primarily to check Nieuwenkamp's interesting results. Access to an exceptionally fine suite of matlockite specimens in the British Museum collection made possible single crystal X-ray measurements, accurate optical determinations, and a new chemical analysis.

Fergusonite from Ceylon

1893 ◽  
Vol 10 (47) ◽  
pp. 234-238 ◽  
Author(s):  
G. T. Prior
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Specific Gravity ◽  
New Mineral

In the appendix to the paper on the new mineral, baddeleyite, in the last number of the Magazine, Mr. Fletcher proves the identity of that mineral with the brazilite of Husssk, and explains the deviation in specific gravity and the original incorrect determination of the chemical composition of the Brazilian mineral by the supposition that the crystallographic measurements were made on the true mineral, while the specific gravity determination and chemical analysis were made on another, a tantalo-niobate of yttrium associated with it.

scholarly journals THE HYGIENIC ASSESSMENT OF THE WORKING ENVIRONMENT IN INDIVIDUAL OCCUPATIONS IN BUILDING ORGANIZATIONS

2018 ◽  
Vol 97 (12) ◽  
pp. 1203-1209 ◽  
Author(s):  
Olga I. Kopytenkova ◽  
Z. Sh. Tursunov ◽  
A. V. Levanchuk ◽  
O. V. Mironenko ◽  
N. M. Frolova ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Health Risk ◽  
Work Experience ◽  
Building Materials ◽  
New Technologies ◽  
Mineral Wool ◽  
Working Environment ◽  
Dust Particles ◽  
Health Work

Introduction. The development of the construction industry is accompanied by the use of new technologies and building materials. Materials based on mineral wool (MW) became to be widely used. The article presents the results of the study of working environment factors and the determination of the safe for health work experience based on the health risk calculation for workers in contact with MW. Material and methods. To quantify the air pollution of the working area at the construction site, samples were taken using an aspirator and a dust meter. An absorption method using a spectrophotometer was used to determine the chemical composition of the dust. Statistical analysis and mathematical modeling were carried out using a standard software package Microsoft Excel, STADIA. Results. A table for the rapid health risk assessment of workers in contact with MW was developed. The risk of health loss is determined as “High” (R = 11.3). Discussion. Working conditions under the performance of heat-insulating works at facades cladding with the use of MW are classified as harmful (class 3.2) on the dust content in working zone air. In the course of the study, coarse dust and fine dust were found in the air. The data on the change of the dust concentration depending on air humidity, the concentration of dust particles of different dispersion at different distances from the place of work is presented. The chemical composition of dust is presented, the presence of heavy metals is established. Dependences for the determination of safe for health work experience under the influence of the various concentration of dust and the duration of contact are constructed. Сonclusions. On the basis of the research to improve the legal support in the field of occupational health and safety, a number of activities for workers engaged in work with the use of MW are proposed.

scholarly journals Application of FT NIR spectroscopy in the determination of basic chemical composition of pork and beef

2011 ◽  
Vol 51 (No. 8) ◽  
pp. 361-368 ◽  
Author(s):  
J. Mlček ◽  
K. Šustová ◽  
J. Simeonovová
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Cross Validation ◽  
Correlation Coefficients ◽  
Nir Spectroscopy ◽  
Calibration And Validation ◽  
Meat Composition ◽  
Calibration Models ◽  
Predicted Values

The objective of this paper was to determine basic components of pork and beef (fat, protein, water content) using FT NIR spectroscopy. The samples were analysed on an FT NIR Nicolet Antaris device in a reflec-tance regimen. Reference results from classical analyses were used for the calibration of the device. Calibration models were created using PLS algorithm (method of partial least squares) and verified by cross-validation. High correlation coefficients (R) of calibration were calculated (fat 0.998; protein 0.976; water 0.994), and subsequently of validation as well (fat 0.997; protein 0.970; water 0.993) and very low standard deviations of the calibration and validation (SEC, SEP). No statistically significant differences between the reference and predicted values of determination were detected in Z-test. According to the published results, the NIRS method has a high potential to replace an expensive and time demanding chemical analysis of meat composition.  

A relation between the density and refractive index of silicate glasses, with application to the determination of imitation gem-stones

1929 ◽  
Vol 22 (126) ◽  
pp. 136-154 ◽  
Author(s):  
F. A. Bannister
Keyword(s):  
Refractive Index ◽  
Chemical Composition ◽  
Chemical Analysis ◽  
Silicate Glasses ◽  
The Other ◽  
Systematic Method ◽  
Natural Glass ◽  
Approximate Composition

It has long been possible to identify readily many minerals by means of density and refractive index determinations, and the chemical composition also can often be approximately deduced. Tilley has shown that it is practicable to determine any natural glass by this method and be succeeded in separating the natural glasses into groups characterized by certain limits of specific refractivity. As far as the author is aware, no such systematic method has been described for distinguishing the artificial glasses one from the other, and it is these glasses that we are concerned with in attempting to determine the approximate composition of an imitation gem-stone without the aid of chemical analysis.

Kerusakan Pada Material Pipa Air Bersih Akibat General Corrosion

2019 ◽  
Vol 16 (2) ◽  
Author(s):  
M. N. Setia Nusa
Keyword(s):  
Chemical Composition ◽  
Failure Analysis ◽  
External Surface ◽  
Internal Surface ◽  
General Corrosion ◽  
Water Pipe ◽  
Corrosion Attack ◽  
Corrosion Failure ◽  
Environment Factor

Water pipe of 4.5” diameter and has been operated for 8 year having failure due to corrosion attack on its external and internal surface. It is conducted failure analysis to find out the cause of corrosion by having testing examination of visual fractography, metalography,, SEM EDAX, hardness and chemical composition. Testing and examination results show that the failure / corroded pipe has a for in of general corrosion on the external surface due to environment factor or ground factor arround the pipe and on the internal surface was influenced by excessive root weld creating protrude which then causing turbolens and deposite to accelerate corrosion attack.Pipa berdiameter 4.5” yang berfungsi mengalirkan air bersih dan telah beroperasi selama 8 tahun, terjadi kerusakan berbentuk korosi pada permukaan luar pipa dan permukaan dalam. Untuk itu dilakukan analisa kerusakan untuk mengetahui penyebab terjadinya korosi dengan pengujian dan pemeriksaan secara visual,Fractography, Metallography, SEM, EDAX, Uji Kekerasan dan Uji Komposisi Kimia. Hasil pemeriksaan dan pengujian pada pipa yang rusak / korosi berbentuk jenis general korosi pada permukaan luar pipa yang diakibatkan faktor lingkungan atau tanah disekitar pipa, sedangkan pada bagian dalam pipa dipengaruhi oleh adanya lelehan pengelasan yang kurang sempurna sehingga menimbulkan benjolan yang mengakibatkan aliran air didalam pipa tidak lancar sehingga terjadi turbolensi yang menimbulkan endapan dan mengakibatkan percepatan terjadinya korosi.Keywords: Pipe, environtment, turbolens, corrosion, failure

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