Lifetime Assessment of the Technological Equipment for a Robotic Workplace

2020 ◽  
Vol 12 (09) ◽  
pp. 2050097 ◽  
Author(s):  
Jozef Bocko ◽  
Ingrid Delyová ◽  
Peter Frankovský ◽  
Vojtech Neumann
Keyword(s):  
Service Life ◽  
Base Material ◽  
Strength Analysis ◽  
Technological Equipment ◽  
Fatigue Design ◽  
Technical Practice ◽  
Technological Unit ◽  
Common Causes ◽  
Design Production

In technical practice, problems associated with material fatigue often arise. These problems can be caused by errors in the stages of design, production or use of the structure, e.g., by incorrect determination of service life, incorrect dimensioning of construction details, incorrect welds, etc. In the case of welds, such issues may be caused due to the fact that the base material is not welded through or due to the presence of a fistula inside the weld, the presence of slags or cracks inside the weld, etc. The task of the designer is to design a technological unit that meets all the requirements of future users. Components have to be designed for fatigue so that there is an acceptable level of probability that their operation will be satisfactory during their operation life. One of the most common causes of failure of welded joints is fatigue. Fatigue design life is understood to be the reference period of time during which the structure is required to serve safely and not to fail with an acceptable probability. This article deals with the assessment of service life of a welded supporting structure of technological equipment. The structure was subjected to strength analysis. The obtained FEA results were needed to plot the extreme amplitudes of the stresses. Based on the obtained stress vibrations and the welds used, the service life of the structure was assessed by means of the standard.

DEFINITION OF TIME SPENT ON REPAIR OF BUS TRANSMISSION UNITS TAKING INTO ACCOUNT TECHNOLOGICAL EQUIPMENT RELIABILITY

2020 ◽  
Vol 2020 (9) ◽  
pp. 29-33
Author(s):  
Sergey Bulatov
Keyword(s):  
Negative Impact ◽  
Probabilistic Method ◽  
Technological Equipment ◽  
Quality And Safety ◽  
Transmission Unit ◽  
Equipment Reliability ◽  
Hours Of Work ◽  
Definition Of ◽  
Time Decrease

The paper purpose is the effectiveness estimation in the technological equipment use, taking into account its reliability and productivity for defective transmission units of buses. The problem consists in the determination of time to be spent on repair of bus transmission units taking into account technological equipment reliability. In the paper there is used a probabilistic method for the prediction bus transmission units, and also a method of the dynamics of averages which allow ensuring minimum of costs for units downtime during repair and equipment cost. The need for repair of transmission units (gear box) arises on an average after 650 hours, the average productivity of the bench makes 4.2 bus / hour. The bench fails on the average after 4600 hours of work, the average time of the bench makes 2 hours. In such a way the solution of the problem specified allows analyzing the necessity of time decrease for transmission unit repair to avoid long downtimes of buses in repair areas without negative impact upon high repair quality and safety during the further operation.

Designing of Outriggers for the Needs of the Vehicles Stability Testing

2018 ◽  
Vol 875 ◽  
pp. 71-76
Author(s):  
Victor Kryaskov ◽  
Andrey Vashurin ◽  
Anton Tumasov ◽  
Alexey Vasiliev
Keyword(s):  
Coefficient Of Friction ◽  
Computer Aided Design ◽  
Strength Analysis ◽  
Direct Impact ◽  
Stability Testing ◽  
Supporting Surface ◽  
Stability Tests ◽  
Computer Aided ◽  
Aided Design

This paper is dedicated to the issues of designing of outriggers for avoidance of vehicle tilting during its stability tests. An analysis of existing types of outriggers was done by authors as well as legislative requirements on them. The reliable and well-timed operation of outriggers largely depends on the height of their positioning on a vehicle. In order to determine this important parameter a special methodic of determining the tipping angle of the vehicle with the use of computer-aided design (CAD) was composed by authors. The article also contains some main principles of strength analysis of the structure a very important part of which became the necessity of determination of coefficient of friction between the outrigger sliders and the supporting surface. This coefficient has a direct impact on the value of transverse forces appearing at the ends of outrigger beams.

scholarly journals Strength Analysis of Alternative Airframe Layouts of Regional Aircraft on the Basis of Automated Parametrical Models

Aerospace ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 80
Author(s):  
Dmitry V. Vedernikov ◽  
Alexander N. Shanygin ◽  
Yury S. Mirgorodsky ◽  
Mikhail D. Levchenkov
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
High Performance ◽  
Strength Analysis ◽  
Labor Input ◽  
Aerodynamic Loading ◽  
Aspect Ratios ◽  
Wide Range ◽  
Parametrical Design

This publication presents the results of complex parametrical strength investigations of typical wings for regional aircrafts obtained by means of the new version of the four-level algorithm (FLA) with the modified module responsible for the analysis of aerodynamic loading. This version of FLA, as well as a base one, is focused on significant decreasing time and labor input of a complex strength analysis of airframes by using simultaneously different principles of decomposition. The base version includes four-level decomposition of airframe and decomposition of strength tasks. The new one realizes additional decomposition of alternative variants of load cases during the process of determination of critical load cases. Such an algorithm is very suitable for strength analysis and designing airframes of regional aircrafts having a wide range of aerodynamic concepts. Results of validation of the new version of FLA for a high-aspect-ratio wing obtained in this work confirmed high performance of the algorithm in decreasing time and labor input of strength analysis of airframes at the preliminary stages of designing. During parametrical design investigation, some interesting results for strut-braced wings having high aspect ratios were obtained.

Mechanical Behaviour of CoCrMo Alloy with Si Content

2015 ◽  
Vol 754-755 ◽  
pp. 1017-1022 ◽  
Author(s):  
Petrică Vizureanu ◽  
Mirabela Georgiana Minciună ◽  
Dragoş Cristian Achiţei ◽  
Andrei Victor Sandu ◽  
Kamarudin Hussin
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Testing Machine ◽  
Base Material ◽  
Optical Emission ◽  
Experimental Tests ◽  
Optical Emission Spectrometry ◽  
Emission Spectrometry ◽  
Standard Samples

.The paper present aspects about the obtaining of non-precious dental alloys (type CoCrMo and CoCrMoSi7), the determination of chemical composition by optical emission spectrometry and the experimental tests for determining the tensile strength, made on standard plate samples. The base material used in experiments was a commercial alloy, from CoCrMo system, which belongs to the class of dental non-precious alloys, intended to medical applications. The obtaining of studied alloy was made on arc re-melting installation, under vacuum, type MRF ABJ 900. The process followed to realize a rapid melting, with a maximum admissible current intensity. The samples for tests were obtained by casting in an electric arc furnace, under vacuum, in optimal conditions for melting and solidification and processing by electro-erosion, to eliminate all the disturbing factors which come by processing conditions for the samples. The determination of chemical composition for cobalt based alloys, by optical emission spectrometry, was made on SpectromaxX equipment with spark. The electrical discharge is made with the elimination of an energy quantity, fact which determine plasma forming and light issue. Tensile tests for standard samples, made from cobalt based alloy, was made on Instron 3382 testing machine, and assisted by computer. The obtained results are: elongation, elasticity modulus, tensile strength and offer complete information about the analyzed mechanical properties. For the certitude of obtained experimental results, the tests were made on samples with specific dimensions according ISO 6892-1:2009(E) standard, both for the tensile strength, and also machine operation.

scholarly journals Determination of the Vertical Load on the Carrying Structure of a Flat Wagon with the 18–100 and Y25 Bogies

2021 ◽  
Vol 11 (9) ◽  
pp. 4130
Author(s):  
Oleksij Fomin ◽  
Alyona Lovska ◽  
Václav Píštěk ◽  
Pavel Kučera
Keyword(s):  
Mathematical Model ◽  
Fatigue Strength ◽  
Service Life ◽  
Dynamic Characteristics ◽  
Dynamic Load ◽  
Field Tests ◽  
Vertical Load ◽  
Mathcad Software ◽  
The Mathematical Model

The study deals with determination of the vertical load on the carrying structure of a flat wagon on the 18–100 and Y25 bogies using mathematic modelling. The study was made for an empty wagon passing over a joint irregularity. The authors calculated the carrying structure of a flat wagon with the designed parameters and the actual features recorded during field tests. The mathematical model was solved in MathCad software. The study found that application of the Y25 bogie for a flat wagon with the designed parameters can decrease the dynamic load by 41.1% in comparison to that with the 18–100 bogie. Therefore, application of the Y25 bogie under a flat wagon with the actual parameters allows decreasing the dynamic loading by 41.4% in comparison to that with the 18–100 bogie. The study also looks at the service life of the supporting structure of a flat wagon with the Y25 bogie, which can be more than twice as long as the 18–100 bogie. The research can be of interest for specialists concerned with improvements in the dynamic characteristics and the fatigue strength of freight cars, safe rail operation, freight security, and the results of the research can be used for development of innovative wagon structures.

Determination of Spacing between Anchored Piles in Row for Deep Foundation Pit

2012 ◽  
Vol 204-208 ◽  
pp. 2736-2739
Author(s):  
Guang Qian Du ◽  
Shi Jie Wang ◽  
Yan Ting Qin ◽  
Chang Zhi Zhu
Keyword(s):  
Strength Criterion ◽  
Strength Analysis ◽  
Soil Arching ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Pile Spacing ◽  
Soil Arch ◽  
Uniformly Distributed Loads

Based on the pile - anchor structure soil between piles,the unified strength theory is introdued in the strength analysis of soil arching between the piles, and parabolic soil arching computational model is uniformly distributed loads ,which are given to meet the soil between piles arch static equilibrium conditions and intensity of conditions , pile spacing formula. Compared with calculations based on the pile spacing of the Mohr-Coulomb strength criterion , the proposed method can consider the contribution of the intermediate principal stress on the strength of the soil arch , the results are more in line with the actual characters of the supporting structure .

scholarly journals Features of the Surface and Subsurface Waves Application for Ultrasonic Evaluation of Physicomechanical Properties of Solids. Part 1. Influence of the Geometrical Parameters

2018 ◽  
Vol 9 (4) ◽  
pp. 325-326
Author(s):  
A. R. Baev ◽  
A. L. Mayorov ◽  
M. V. Asadchaya ◽  
V. N. Levkovich ◽  
K. G. Zhavoronkov
Keyword(s):  
Protective Coating ◽  
Layer Structure ◽  
Base Material ◽  
Protective Layer ◽  
Body Waves ◽  
Measuring System ◽  
Geometrical Parameters ◽  
Small Aperture ◽  
Ultrasonic Evaluation

Application of surface and subsurface waves for control of objects with a double-layer structure allows to extend possibilities of diagnostics of their physico-mechanical properties. The purpose of work was to determine conditions and offer recommendations providing measuring of ultrasonic velocity and amplitude of the former modes in protective layers and in basis of object at one-sided access to its surface.The analysis of an acoustic path of a measuring system in relation to ultrasonic evaluation of the objects having the restricted sizes and the protective coating according to velocity data of the surface and subsurface waves propagation is made. On the basis of representations of beam acoustics the dependences connecting a wavelength of the excited surface and subsurface modes, thickness and width of a controlled object, acoustic base of a sounding are defined. There are to provide a condition leveling of the influence of an acoustical noise created by the reflected and accompanying waves on parameters of acoustic signal with the given quantity of oscillations in an impulse.The principle opportunity is shown and conditions for determination of velocity of subsurface body waves in the base material which is under a protective coating layer are established. For these purposes on the basis of use of the block of ultrasonic probes the optimum scheme of a sounding is offered and the analytical expression for calculation of required velocity considering varying of thickness of a covering is received.The method of acoustical measuring realized by a direct and reverse sounding of the objects with small aperture and angle probes was analysed and formulas for determination of speed of subsurface wave under protective layer of the wedge form have been got. An ultrasonic device is suggested for the excitationreception of subsurface waves with different speed in objects (on 20–35 %) using for the acoustic concordance of environments of metallic sound duct as a wedge. Possibility of leveling of interference in a protective layer to control efects in basis of material by a volume wave by creation of supporting echo-signal of longitudinal wave of the set frequency and entered normally to the surface of object was studied.

scholarly journals Genetic Heterogeneity in GJB2, COL4A3, ATP6V1B1 and EDNRB Variants Detected Among Hearing Impaired Families in Morocco

2021 ◽  
Author(s):  
Imane Aitraise ◽  
Ghita Amalou ◽  
Hicham Charoute ◽  
Mostafa Kandil ◽  
Hassan Rouba ◽  
...  
Keyword(s):  
Auditory Perception ◽  
Conduction Mechanism ◽  
Correct Diagnosis ◽  
Hearing Disorders ◽  
Deafness Gene ◽  
Whole Exome ◽  
Common Causes ◽  
Sound Conduction ◽  
Moroccan Patients

Abstract Deafness has a very variable disease. It may occur as a result of external auditory canal involvement or a deficiency in the sound conduction mechanism (transmission deafness) or impairment of the cochlear, cochlear nerve or central auditory perception. Genetics is the most common cause, as approximately 70% of hearing disorders are of hereditary origin. 1/3 of hereditary deafness is syndromic (associated with other symptoms) and 2/3 are non-syndromic (isolated deafness). At this date, 173 loci of deafness gene have been reported in the literature (69 DFNA, 94 DFNB, 6 X-linked DFN, 2 DFNM, 1 DFNY and 1 AUNA1). For syndromic deafness, approximately 400 syndromes associated with hearing disorders are already described. Thus, the determination of causal mutations is a valuable aid for accurate and early diagnosis. This makes it possible to better guide the management since forms of deafness respond better to the cochlear implant than others. The correct diagnosis also gives an idea of ​​the evolutionary profile of deafness and whether it is a syndromic deafness requiring special surveillance. In this study, we have examined the genetic causes of sensorineural hearing loss in Moroccan patients through whole exome sequencing (WES) to identify candidate genes for six severely deaf Moroccan families. The results revealed four genetic variants in the genes GJB2, COL4A3, ATP6V1B1 and EDNRB, which are therefore common causes of syndromic and non-syndromic deafness.

scholarly journals Stored Energy of Plastic Deformation in Tube Bending Processes

2013 ◽  
Vol 18 (1) ◽  
pp. 235-248 ◽  
Author(s):  
Z. Śloderbach ◽  
J. Pająk
Keyword(s):  
Plastic Deformation ◽  
Service Life ◽  
Plastic Strain ◽  
Analytic Method ◽  
Stored Energy ◽  
Tube Bending ◽  
Cold Bending ◽  
Tension And Compression

The paper presents an aproximate analytic method for determination of the stored energy of plastic deformation during cold bending of metal tubes at bending machines. Calculations were performed for outer points of the tube layers subjected to tension and compression (the points of maximum strains). The percentage of stored energy related to the plastic strain work was determined and the results were presented in graphs. The influence and importance of the stored energy of plastic deformation on the service life of pipeline bends are discussed.

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