Product Design, Robotics, Advanced Mechanical and Mechatronic Systems and Innovation Conferencedoi: 10.1088/1757-899X/514/1/011001pmid: N/A
PRASIC 2018, 8 – 9 November 2018The 10th edition of the PRASIC Conference was hosted in Brasov on 8-9 November 2018.The PRASIC‘18 Conference is dedicated to scientific research in the field of mechanics, machine elements, industrial robots, advanced mechanics and mechatronic systems, tribology, and also in education, innovation and technology transfer, industrial management, mechanics and machine history.The beginning was in 1982 under the name of PRASIC (Computer Aided Design), at the initiative of Professor Ioan Drăghici. At the beginning only the scientific researches related to Mechanisms and Machine Elements were treated, from 1996 Robotics was added, and then other scientific concerns related to them.In 2006, it was the last edition having as sections mechanisms, Machine Elements and Robotics. In 2016 PRASIC was renamed, being Product Design, Robotics, Advanced Mechanics & Mechatronic Systems, and Innovation Conference, keeping the brand PRASIC, well known in Romania and also outside, having an important history, and also keeping a high quality standard for scientific papers.At the 2018 edition, 48 papers were selected on 9 sections, with the participation of colleagues from university centers such as: Politehnica University of Bucharest, Gh. Asachi Iasi University, Technical University of Cluj Napoca, Stefan cel Mare University of Suceava, University Constantin Brancusi Tg. Jiu, Dunarea de Jos University of Galati, Politehnica University of Timisoara, University of Craiova, Petroleum and Gas University of Ploiesti, Technical University of Moldova Chisinau.The scientific opening of the Conference was provided by Professor Alberto Canen of Coppe University, Rio de Janeiro, Brazil and Professor Valeriu Dulgheru of the Technical University of Moldova. Conference papers were submitted for publication at the IOP Publishing Conference Series - Materials Science and Engineering.Organizing Committee,Professor Dan SĂVESCU
Peer review statementdoi: 10.1088/1757-899X/514/1/011002pmid: N/A
All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.
Influence of the roughness on surface geometry of rolling contactsBenchea, M; Creţu, S
doi: 10.1088/1757-899X/514/1/012001pmid: N/A
The topography of the active surfaces in rolling contact depends on the surface roughness obtained by different manufacturing process technology (turning, grinding, polishing, lapping, etc.). The aim of this paper work is to evidence the influence of the surface roughness on surface geometry of rolling contacts. The experimental tests were carried out on the AMSLER machine and an experimental setup for pure rolling motion. The surfaces of the rolling samples were analyzed with SEM (scanning electron microscopy) and EDS (energy dispersive X-ray spectroscopy) techniques for structural and chemical analysis and measured with the Taylor Hobson profilometer before and after the experimental tests for surface topography.
Employment of hyper-cycloidal oscillatory motion for finding the coefficient of rolling friction. Part 2: Experimental investigationCiornei, F C; Pentiuc, R-D; Alaci, S; Romanu, I C; Irimescu, L; Buium, F
doi: 10.1088/1757-899X/514/1/012003pmid: N/A
The paper presents a method for finding the characteristics of rolling friction between two cylindrical external surfaces. By choosing the motion between two parallel cylinders it results that a point from one of the cylinders describes a hyper-cycloidal curve when rolling over the other cylinder. The study is focused on the friction in ball bearings. Parts of the ball bearings to be studied are directly involved in materializing the hyper-cycloidal contact. Thus, the immobile circles are materialized by the outer surface of the external ring and the mobile circles are materialized by the spherical surfaces of the balls. The motion of a laser stick attached to the pendulum is filmed. Analyzing the movie, the numerical time dependence of angular amplitude decrease is obtained. The concordance between the experimental and theoretical angular amplitude damping directs to the value of coefficient of rolling friction.
An improved technique of finding the coefficient of rolling friction by inclined plane methodCiornei, F C; Pentiuc, R D; Alaci, S; Romanu, I C; Siretean, S T; Ciornei, M C
doi: 10.1088/1757-899X/514/1/012004pmid: N/A
During the design process the mechanical engineer faces a challenge: the choice of the tribological parameters. Even most influential technical references offer ranges for the frictional characteristics. An emblematic example is the coefficient of rolling friction (CRF). The handiest solution in establishing the correct value of the CRF for a certain contact is to find it experimentally. One of the methods is the inclined plane manner. The weak point of the method consists in the particularly small values of the slope required to evidence the effect of rolling friction. The present work shows a technique for finding the CRF. The principle of the method consists in considering both the slope of the inclined plane and the torque of rolling friction as unknowns. The two parameters can be established by experimental finding of the acceleration of an axi-symmetric body, both for ascending and descending motions.
Method for simultaneous estimation of rolling and spinning friction in a higher pairAlaci, S; Pentiuc, R D; Ciornei, F C; Romanu, I C; Siretean, S T; Ciornei, M C
doi: 10.1088/1757-899X/514/1/012005pmid: N/A
A spatial higher pair is characterized by a complex motion with the direct consequence: the occurrence in the contact point of a friction torsor having all possible components (sliding, spinning and rolling friction). There are cases, like thrust ball bearings, where the components of the friction torsor are interrelated, and actual separation of these is not possible. The present paper proposes an approach for simultaneous evaluation of the coefficient of rolling friction and of the coefficient of spinning friction using a cycloidal pendulum. As principle, the experimental device consists in a steel ball set on top of two cylindrical steel rods, parallel, mounted horizontally. When a vertical rod is attached to the ball, a cycloidal pendulum is obtained. The damping of oscillatory motion is due to the two friction torques: spinning and rolling. y relevant articles in literature searches, great care should be taken in constructing both. The motion of the pendulum is analyzed for two values of the gap between the horizontal rods. A system of two equations with the coefficients of rolling and spinning friction as unknowns is obtained. Based on the hypothesis that the dependencies for the torques versus the normal force are known, these two coefficients can be obtained.
Subsurface analysis of 6082-T6 Aluminium alloy’s mechanical properties subjected to small particles erosionErdoğan, A A; Țarcă, I C; Rus, A; Țarcă, R C
doi: 10.1088/1757-899X/514/1/012006pmid: N/A
6082-T6 aluminium alloy is a ductile metal. When subjected to small particles erosion, sub-surface deformations are expected due to the particle impact. Plasticity is one of the properties which might reveal the rate of the deformations. As a result of plastic deformation, mechanical properties of the samples are expected to change with distance from the surface. Typically, the depth of the plastically deformed region could be between 5 and 200 μm. In order to understand the plasticity of the materials, nanoindentation researches were conducted. Aluminium alloy samples were previously subjected to hard material particles jets (Al2O3) under different values of incident angle, between 15 and 90 degrees. After a 3D scan of the resulted surfaces, the samples were cut in such a manner that the middle section remained visible and prepared for nanoindentation analysis. The paper presents the experiments conducted as well as some of the achieved results.
Experimental Researches concerning the Rheology of Cutting FluidsRadulescu, I; Radulescu, A V; Ramalchanov, S; Yankov, S; Rupetsov, V S
doi: 10.1088/1757-899X/514/1/012007pmid: N/A
Cutting fluids are used to reduce the negative effects of the heat and friction on both tool and work piece. The cutting fluids produce three positive effects in the process: heat removal elimination, lubrication on the chip–tool interface and chip removal. This paper proposes to study the rheological properties of four different type of cutting fluids, as function of their chemical and physical characteristics. The tests were performed using a cone and plate Brookfield viscometer, by determining the rheological parameters and the variation of the apparent viscosity with the temperature. This approach has been used to quantify the performance of the tested products and to compare products in the marketplace.
Evaluation of the corrosion wear speed of different equipment in the water injection treatment plantDudu, C; Ripeanu, R G; Drumeanu, A C; Dinita, A; Lospa, A M
doi: 10.1088/1757-899X/514/1/012008pmid: N/A
The paper presents the results of the theoretical and experimental researches carried out for the evaluation of the corrosive rate of different equipment from water injection treatment plant used for water flooding. The degradation are occurring mainly at pipelines and connecting elements of the flotation skid, in the form of advanced corrosion wear because the water injection contains an inconsistent composition mixture of dissolved gases, hydrocarbons, solid particles. The manifestation of corrosion wear at the skid connections indicates that the mechanical-physical-chemical treatments used to reduce aggressiveness are not sufficiently effective. The tests were carried out on the corrosion specimens taken from the critical areas of the skid connections and using the different formation water taken from the same critical points. Corrosion rate was obtained through experimental tests made in accordance with ASTM G5-15 and ASTM G1-03. The results materialized in the form of an influence of corrosion inhibitor and temperature on the corrosion rate for different formation water samples.