ON THE TECHNOLOGY OF A SINTERED MAGNETIC POLE
It is presented the technology of a sintered magnetic pole and the research needed to attain the necessary magnetic properties. It is started with iron powder, blended with lubricants, pressed in a double action die, sintered, and calibrated.
Keywords: iron powder, pressing, sintering, calibration
DEVELOPMENT OF MECHATRONIC SYSTEMS OF MULTIAGENT SYSTEMS FOR CYBER PHYSICAL SYSTEMS
This paper brings into question one of the major concerns at the global level, to effectively harness the exciting advancements in science and information technology, communication and leadership. The integration of computers into the physical processes involved in the emergence of large, complex systems, interconnected objects that come with processing capabilities and communication and can improve quality of life. These are the cyber physical systems.
Keywords: mecatronic system, intelligence, cyber physical system interaction
CRANKSHAFT REBUILDING FROM DIESEL FRETTING
This paper presents a method ethnological crankshaft repair of diesel locomotives fitted to power between 450 and 1250 HP. Repair of crankshaft technology apply to broken trees. The method applied is achieved by assembling Fretting two shaft ends broken.
Keywords: tree, relieving, sandifer, diesel overhaul
FORGING WITH CONTINUOUS FIBROUS STRUCTURE OF LARGE DIMENSIONS CRANKSHAFTS
This paper establishes that the further processing of continuous fibrous structure may cause a progressive break of large crankshafts.
Keywords: crankshafts, continuous fibre, macrostructure, micro chipped, microstructure, purity
INFLUENCE OF STRUCTURE ON THE QUALITY AND FATIGUE STRENGTH OF THE CRANKSHAFT IN SERVICE
This paper is based on experimental researches regarding the influence of structure on the quality and fatigue resistance in exploitation of crankshaft of large dimensions.
Keywords: fatigue, progressive braking, forging lines, fibber, metallographic structure, micrograph
MODIFICATION OF HIGH-ALLOYED STEEL GRADES BY APPLYING A HEAT TREATMENT AND CRYOGENIC (II)
Cryogenic treatment completes the classic heat treatment of steels with higher carbon content of 0.6 %, bringing substantially improving on properties, being very simple. Application of cryogenic treatment immediately after hardening has led to the increase in the percentage hardness of high-alloyed steels HS 18-1-1, RUL1 and X200Cr12 with 26.56 %, 34.5 % and 9.7 %. At the same time, Hardness Vickers values were increased with 41, 49 and 61 units, representing a 4.8 %, 6.3 % and 6.7 %, increase, as a result of martensitic transformation.
Keywords: martensitic transformation, low temperature, optical microscopy, Vickers hardness Cuvinte cheie: transformare martensitică, temperatură scăzută microscopie optică, duritate Vickers
STRUCTURE MODIFICATION OF HIGH-ALLOYED STEEL BY APPLYING A HEAT AND CRYOGENIC TREATMENT (I)
Cryogenic treatment completes the classic heat treatment of steels with higher carbon content of 0.6 %, bringing substantially improving on properties, being very simple. Application of cryogenic treatment immediately after hardening has led to the increase in the percentage hardness of highalloyed steels HS 18-1-1, RUL1 and X200Cr12 with 26.56 %, 34.5 % and 9.7 %. At the same time, Hardness Vickers values were increased with 41, 49 and 61 units, representing a 4.8 %, 6.3 % and 6.7 %, increase, as a result of martensitic transformation.
Keywords: martensitic transformation, low temperature, optical microscopy, Vickers hardness
THE RESEARCH OF EROSION CAVITATION ON STAINLESS STEEL X2CRNIMON22+5+3 HEAT- TREATED
In this paper is presented a comparative analysis between cavitation resistance of stainless steel austenito-feritic and OH12NDL stainless steel (traditional steel). To assess the damage produced by Cecil cavitaţionale implosion over stainless steel duplex X2CrNiMn22 + 5 + 3 tests have been carried out in the laboratory of Cavitation at the University Politehnica Timisoara. The assessment of the data and the interpretation of the characteristic curves of cavitation (loss of mass and speed of erosion) could find that stainless steel X2CrNiMn22 + 5 + 3 heat-treated by quenching followed by tempering the high cavitation resistance exhibited a higher compared with traditional steel OH12NDL.
Keywords: stainless steel, cavitationala erosion, characteristic curves, mass loss, resistance to cavitation
CHANGE THE BRONZE AMPCO 45 RESISTANCE TO CAVITATION BY VARIOUS HARDENING TREATMENTS
This paper presents of the micro hardness effect of the Bronze AMPCO 45 upon resistance to cavitation of erosion, generated to T2 device vibrating piezoelectric crystal, by the Cavitation Laboratory of the Polytechnic University of Timisoara. The micro hardness changing of the exposed surface to the cavitation, by volume heat treatment, laser reminting with three powers in pulse, and by thermal spray, followed by laser reminting, with two powers different in impulse. Research shows that resistance to cavitation erosion tends to grow exponentially with hardness. The greatest strength, namely the average penetration depth of erosion is recorded for the area covered with ceramic powders remitted with laser
Keywords: erosion by the cavitation, the cavitation, the average penetration depth of erosion, the hardness
STOCHASTIC PETRI NETS APPLIED IN THE DISCRETE EVENT
The starting point in developing this work was to choose a Markovian model developed based on stochastic transitions in different locations of the system. This paper is intended as an analysis of a stochastic transport system within a manufacturing system. The system is impracticable to design and analyse research prototype system, manifested in a case study. I chose to represent stochastic Petri nets.
Keywords: stochastic Petri networks, transport system
INTELLIGENT FUNCTIONS OF CNC MACHINE TOOLS
In this paper we try to highlight the advantages of the latest types of CNC machine tools (MUCN – in Romanian language), equipped with smart features on ensuring their maintenance. This becomes evident and is especially beneficial in Romania, where the production of machine tools is quasi nonexistent.
Keywords: System „MULTI-TASKING”, „DONE IN ONE” smart features, 3D, synchronized intelligent maintenance
APPLYING THE SIX SIGMA METHODOLOGY TO DECREASE THE NUMBER OF SCRAPPED PARTS ON A MANUFACTURING LINE
The current paper describes the application of the Six Sigma methodology for reducing the number of scrapped parts on the manufacturing line at Start Transmission. Herein it is shown how the four steps of the method, namely Definition, Measurement and Analysis, Improvement and Control, are applied, as well as the methods and quality tools used.
Keywords: six sigma, Pareto diagram, workflow diagram, control flow diagram
APPRECIATIONS ABOUT THE GOVERNMENT QUALITY ASSURANCE MANAGEMENT
Government Quality Assurance through the competent national authorities shall provide the confidence that the contractual requirements concerning quality are met. The work presents the mutual acceptance of government quality assurance management and usage of the allied quality assurance publications.
Keywords: Government, quality assurance, STANAG 4107
CONTRIBUTIONS ON THE DEVELOPMENT OF A DEVICE FOR MEASURING THE SOUND-ABSORBING COEFICIENT
This paper aims to describe fiction and the components of a device for the determination of sound-absorbing coefficient published [1] în the previous edition and essential elements în implementing the architecture processed and acoustic signals analysis undertaken
Keywords: impedance tube, phono-absorbing coefficient, signal analizer
EVALUATION OF LABORATORY ANALYSIS OF LUBRICANTS AND LUBRICATING PROCESSES IN COMPRESSION IGNITED ENGINES’ MECHANISMS DEPENDING ON BIODIESEL CONTENT IN FUEL
Biodiesel use as fuel is a reality today. It is used in compression ignited engines throughout the entire planet. It may come alone or in mixtures with other fuels, either conventional ones or alternative solutions. Biodiesel itself is a bio-alternative solution for fossil fuels. In the present days the content of biodiesel in commercial fuels throughout the country does not exceed 10 %, but in the coming years it will increase toward 20 % and more. There have to be an extensive knowledge and scientific approach related to the effects that biodiesel has upon engine’s lubricants and lubrication processes. In this paper are presented some studies that were developed toward this specific objective and the significant conclusions which were made possible after the research. There are important influences of the biodiesel use as fuel even in the quality of engine lubrication process.
Keywords: biodiesel, lubrication, compression-ignition engines, engine lubricant, physic-chemical characteristics
STUDIES REGARDING THE INFLUENCE OF BIOFUELS ON THE PERFORMANCE OF CATALYTIC CONVERTERS MOUNTED ON SPARK IGNITED ENGINES In this paper, the problem of study is designed maintenance or performance degradation of catalysts used in catalytic exhaust systems, which equips vehicles powered by an internal combustion engine with spark-ignition, in terms of using a fuel that comprises bioethanol.
Keywords: biofuel, bioethanol, catalytic converter, exhaust system, spark-ignited engines
PERFORMANCE AND ECONOMICITY ANALYSIS OF A DIESEL ENGINE THAT RUNS ON BIODIESEL
The paper aims to analyse through simulation of performance indicators (actual Power and Time effective) and economic indices (actual fuel specific consumption) of an engine operating on biofuels. The simulation program is Lotus Engine Simulation, free software for monocilindrice engines. There have been a series of simulations to highlight the differences between a pure Diesel fuel and B100 (100 % Biodiesel).
Keywords: Biodiesel, Diesel, simulation, Lotus Engine Simulation
THE ANALIZE OF SPECIFIC PARAMETERS FOR SPARK IGNITED ENGINE OPERATIONAL CYCLE DEPENDING ON ALTITUDE
The spark ignited engine is yet one of the most popular thermo-chemical energy converter worldwide used for propelling over 500 million cars today. Some of these vehicles are used in different geographic conditions that alter the engine operating regime usually by increasing fuel consumption and consequently the air pollution in order to maintain the torque and power output performances requested through the driver pedal. Because atmospheric pressure at high altitudes is lower in comparison with the see level, spark ignited engine’s operating conditions are tremendously changed in a 2000 meters of altitude range. The present paper unveils some of the particular engine operating conditions at different altitudes of the road and proposes some solutions and developing perspectives concerning the limitations and problems that occur during field operation. In order to obtain the same power and torque performances at any altitude level the engine operating parameters have to be the same at all times and at all altitudes. By field experimentation the research shows where the problems are; on the other hand, by analyze and interpretation it brings up the proper solutions to the inconveniences.
Keywords: intake, fuel injection, spark-ignited engine, engine performance
ANALYZING THE POSSIBILITIES OF PERFORMANCE IMPROVEMENT OF A CHARGED SI ENGINE BY MODIFYING IT’S DISTRIBUTION PHASES
This paper aims to analyze the possibilities through simulation of performance parameters improvement (mean effective pressure, boost pressure, exhaust flow and engine speed increase to sudden load change) of an engine to its basic version. As simulation software, AVL BOOST was elected, which gives the required accuracy for transient simulations. Simulations compared the engine performance of the various possibilities of amending phase distribution compared to the basic version of the analysed engine. Keywords: performance, distribution phases, simulation, charged
RESEARCES CONCERNING TE USE OF ATERNATIE FUES IN TRANSPORTATION
The present paper analse the actual trends and perspectives on the alternative fuels such are fossil fuels but also biofuels. The greenhouse gases emissions are analsed and compared beteen the most important alternative fuels.
keywords: alternative fuels, biofuels, transportation
EXPERIMENTAL EVALUATION OF CONFORMITY OF URBAN TRANSPORT VEHICLES BODYWORKS
It can be affirmed that the movement has emerged with the advent of motor transport. If the early use of these means of transport, traffic accidents is produced with low frequency, at the present time, due to the unprecedented increase in traffic, traffic accident has become an acute social problem. As a result, over time, it has acted in the following three major directions: the traffic. Regulation by a legal system, increase the level of performance of active safety provided by the motor vehicle, increasing the level of passive safety performance ensured by the motor vehicle.
Keywords: vehicle, bodywork, experimental testing
COMPUTATIONAL FIRE SIMULATION TO A CAR IN A SEMICLOSED SPACE
The article presents the work of the authors concerning the 3D fire simulation at a semi closed space involving one stationary car. A simulation using Pyrosim software is based on the physical model in which one electrical fault accident involving a car appear. The accident, consisting in a fire event at one stationary car, is modelled at 1.5 m from height. Considering an electrical fault followed by a fire, we obtained temperature fields and smoke spread depending on time in this tunnel. These information allow us to realize an appropriate impact on the event in aim of minimizing the time for a promptly intervention.
Keywords: road tunnel fire, heat release rate, Pyrosim software
ELECTRIC VEHICLES
This article presents the advantages and disadvantages propulsive vehicle with an electric motor. This type of propellant can replace thermal engines with high efficiency.
Keywords: electric motor, the hybrid vehicle, Lithium-Ion battery
CONTRIBUTIONS BY VIBRATION MEASUREMENTS TO STUDY SUBMITTED HUMAN BODY
This paper contains a study on the effects of vibration and permissible limits human. Complexity factors acting on the body and need precise measurements of vibrations imply reliability and precision. By using devices SVAN 958 and IHVM 100 is successfully creating precision measurements and also being portable allowing easy movement to any area for fast setup.
Keywords: vibration, effects, extent, medium
PROJECTIL PROPULSION BY ELECTROMAGNETIC FORCE
The paper presents experiments using a laboratory model at small scale for a “coil gun” type projectile launcher. Electromagnetic acceleration of a mobile fitting by a coil (stator) travelled by an electric current is a phenomenon known in the 18th century and knows many applications of this phenomenon. Explanation refers to what passes through the stator currents and armour as well as mutual inductance variation of these. Inductance mutual values are found by means of approximation.
Keywords: electromagnetic force, projectile, ballistics parameters
TEMPERATURE EFFECT UPON THE NATURAL FREQUENCIES OF THRUSS ELEMENTS
In this paper we analyze the effect of temperature upon the natural frequencies of truss elements. Temperature changes influence the Young’s modulus in the sense that it decreases with increasing temperature, consequently structural elements frequencies decrease. However, we demonstrate in this paper that the frequency changes due to temperature in natural environment are very small and do not dramatically influence the structures dynamic behavior.
Keywords: temperature, Young modulus, frequency, truss structures
CONSIDERATION REGARDING THE NON INVASIVE EFFECTS OF NOISE ON THE CIVILE CONSTRUCTIONS WORKERS
This paper contains considerations about the noise effects on the health of workers. There are definition of the noise and the causes of the noise pollution în our modern society and describe the negatives effects of the higher noise level that the workers has to deal with în the construction sites.
Keywords: noise, non invasive effects of noise level limits