Arhive zilnice: mai 6, 2017

32-67 ROMANIAN ALL – TERRAIN SUPPLY VEHICLE (RATSV) – MINIROBOT DESTINAT APROVIZIONĂRII STRUCTURILOR LUPTĂTOARE DISLOCATE ÎN ZONELE MONTANE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Silviu Mihai PETRIŞOR Vlăduţ DINESCU la de

ROMANIAN ALL – TERRAIN SUPPLY VEHICLE (RATSV) – MINI ROBOT INTENDED FOR THE SUPPLY OF THE COMBAT STRUCTURES DEPLOYED IN MOUNTAINOUS AREAS

 

In the present paper the authors describe the construction of an innovative functional model of tracked mini robot intended for the supply of troops deployed in hard to reach areas, such as mountainous ones or those that involve a high degree of risk for the human operator; this is a solution meant to support the future potential construction of innovative prototypes of mini robots designed for these missions and tasks. We present in the paper the assembly, the operation and the role of the body parts chosen for the construction of the tracked mini robot variant, describing, in detail, the advantages and the opportunities to valorise this present technological product during the assigned missions.

 

Keywords: tracked mini robot, human-artificial “partnership”, modularized structure, special applications, hard to reach areas

Cuvinte cheie: minirobot şenilat, “parteneriat” uman-artificial, structură modularizată, aplicaţii speciale, zone greu accesibile

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32-66 CONSIDERAȚII PRIVIND IMPACTUL DINTRE UN PARAPET DE PROTECȚIE ŞI UN PENDUL

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Maria – Adriana CORDOȘ Mircea BEJAN la de

CONSIDERATIONS REGARDING THE IMPACT OF A PROTECTIVE BARRIER AND A PENDULUM

 

The paper presents the impact of a pendulum with a weight of 2780 kg and a road protective barrier used on the roads of Romania. Deformable parapets are very important to protect the pedestrians and the vehicles on our roads. The maximum dynamic deflection of the parapet, measured after the test was 0,240 m and 0,435 m of working width.

The barrier was deformed as expected. Damping elements have taken a large amount of energy during impact. The pendulum is used by researchers in this field. This is a very good way to track the behavior and damping elements of the barriers in the laboratory.

 

Keywords: shock test, road restraint systems

Cuvinte cheie: încercare la şoc,  sisteme de reținere rutiere

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32-65 TESTE EXPERIMENTALE PE DISCUL BIPLAN AL VANEI FLUTURE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cristian Marius MIMIS Tiberiu Ștefan MĂNESCU la de

EXPERIMENTAL TESTS ON A BUtTERFLY

VALVE BIPLAN DISC

 

The paper present the obtained experimental results after laboratory tests on a butterfly valve biplane disc by using electrical resistive tensometry method. Measuring the variation of the sensor’s resistance through electrical methods is proportionally with its elongation and the deformation of the part of the butterfly valve disc. The measured elongations for three static loads applied on the valve disc are presented.

 

Keywords: deformations, biplane butterfly valve disc, tensometers electro-resistive

Cuvinte cheie: deformaţii, disc biplan vană fluture, tensometrie electro-rezisitivă

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32-64 REZULTATE PRELIMINARE PRIVIND UTILIZAREA METODEI CORELĂRII DIGITALE A IMAGINII ÎN STUDIUL IMPLANTURILOR DENTARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniel-Tamás SZÁVA Gabriel POPA Holger HOŢA Ildikó-Renáta SZÁVA Ioan SZÁVA Pál Botond GÁLFI la de

PRELIMINARY RESULTS CONCERNING ON THE IMPLEMENTATION OF THE VIDEO IMAGE CORRELATION METHOD IN THE DENTAL IMPLANTS ANALYSIS

 

The authors, in their preliminary investigations [1; 2; 3], conceived an original testing bench, destined to human mandibles’ strain-state evaluation.

Involving the mentioned testing bench, the authors started to perform some preliminary experimental investigations in several dental implants’ behaviours.

In the described investigations, the authors some useful correlations between the dental implant’s positioning on the mandible, the applied mastication force magnitude and its relative 3D positioning with respect to the implant’s longitudinal axis.

Their next topic will consist in a searching examination of the optimal positioning of the implants, with respect to their loading conditions.

One has to underline the fact that the proposed original methodology will represent in the next period a high-accuracy approach in the evaluation of the strain-state analysis of the dental implants.

 

Keywords: dental implant, testing bench, displacement field, Video Image Correlation

Cuvinte cheie: implant dentar, stand de încercat implanturi, câmp de deplasare, Corelare Digitală a Imaginii (VIC)

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32-63 CONSIDERAȚII ASUPRA TENSIUNILOR ȘI DEFORMAȚIILOR DIN CADRELE PRESELOR DE MARE TONAJ

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniel Gheorghe LAKATOS Ioan VIDICAN Marius PÂSLĂ Mircea BEJAN la de

CONSIDERATIONS ON THE FRAMES STRESSES

AND STRAINS HEAVY PRESSES

 

In paper presents a theoretical study of the state of stress and strain in the machine frame framework heavy press. These frameworks are made up of a plurality of frames each comprised of two closed C-shaped elements (calipers) connected by tightening by means of threaded rods (Fig. 1)

 

Keywords: press, frame, strength, stress, deformations, thrusts

Cuvinte cheie: presă, batiu, forță, tensiuni, deformații, tirant

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32-62 APLICATII ALE METODELOR NUMERICE DE CALCUL ÎN ANALIZA COMPORTĂRII VANELOR FLUTURE BIPLANE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Cristian Marius MIMIS la de

APPLICATIONS OF THE NUMERICAL METHODS IN ANALYZE THE BEHAVIOR OF BIPLANE BUTTERFLY VALVES

 

The paper presents the elongations obtained by numerical results on a butterfly valve biplane disc by using finite element method and these values were compared with elongations resulted from laboratory tests for three levels of water pressure applied upstream the biplane disc. The comparison between two methods to determine the elongation it shows that the finite element method applied to the disc can replace electrical resistive tensometry, to compute stresses and deformations for biplane butterfly disc on an industrial scale.

 

Keywords: finite element method, disc biplane specific strain

Cuvinte cheie: metoda elementelor finite, disc biplan, deformaţii specifice

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32-61 ANALIZA STĂRII DE TENSIUNI ŞI DEFORMAŢII ÎN CORPURILE DE RULARE DE MICI DIMENSIUNI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gelu BĂLAN Ovidiu MILOȘ Tiberiu Ștefan MĂNESCU Vasile IANCU la de

STRESS AND STRAIN ANALYZE OF

SMALL ROTATION BODIES OF BEARINGS

 

In the paper is presented the study of tensions and strains ho appears in small radial roller bearings during the compressive strength testing caused by forces acting perpendicular to the roller generator. For modelling a roller bearing Ø 16×24 [mm] we used SolidWorks program, the tests were conducted on two types of rollers with and without defect loaded in five-speeds charging.

 

Keywords: reel, bearing, local deformation, finite element

Cuvinte cheie: rolă, rulment, deformaţie locală, elemente finite

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32-60 STUDIUL STĂRII DE TENSIUNI ȘI DEFORMAȚII ALE ROLELOR DE RULMENT PRIN MODELARE CU METODA ELEMENTELOR FINITE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gelu BĂLAN Ovidiu MILOȘ Tiberiu MĂNESCU jr. Vasile IANCU la de

STRESS AND STRAIN STUDY OF THE ROLLER BEARINGS USING FEM METHOD

 

This paper aims to study the stresses and strains that occur in small radial bearings with rolls of Æ 7,5×15 mm diameter. We have considered five-speed charging for two distinct cases: without and with defects.

 

Keywords: roller bearing, contact voltage, strain, roll flange

Cuvinte cheie: rulment radial, tensiune de contact, deformație, rolă-placă plană

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32-59 EFICIENŢA DIFERIŢILOR ESTIMATORI AI DISIMILARITĂŢII UTILIZAŢI ÎN DETECTAREA DEFECTELOR

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gilbert Rainer GILLICH Ionela PELEA Nicoleta GILLICH la de

THE EFFICIENCY OF SEVERAL DISSIMILARITY ESTIMATORS USED IN DAMAGE DETECTION

 

This paper deals with damage detection methods based on interpreting the results of vibration measurement. We briefly described an own method for damage evaluation, which takes into account a large number of frequencies achieved from weak axis bending modes. This allows the precise location of the defect location. We represented two histogram types, one with measurements and several resulted from calculations for possible damage scenarios. The damage location was determined with three estimators, among those the best results being attained with the Minkowski distance.

 

Keywords: damage, severity assessment, natural frequencies, vibration

Cuvinte cheie: defecte, evaluarea severității, frecvenţe naturale, vibraţii

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32-58 MODIFICAREA DISTRIBUŢIEI TENSIUNILOR ÎN ZONA DEFECTULUI ŞI EFECTUL ACESTEIA ASUPRA FRECVENŢELOR PROPRII ALE GRINZII

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gilbert Rainer GILLICH Luminiţa PĂDURARU Marius TUFOI la de

STRESS DISTRIBUTION ALTERATION IN THE DAMAGED ZONE AND ITS EFFECT ON THE BEAM’S NATURAL FREQUENCIES

 

In this paper the relation to be used for deriving the frequency of a beam with transverse crack is tested against finite elements method (FEM) simulation results. We have first analytically derived the beam deflection and compared with results achieved by means of the FEM simulation. The good concordance was found, thus the FEM model is calibrated. Afterwards, damage of different depth was introduced in the beam and the natural frequencies derived. These values were compared against results attained by applying the proposed relation and a good fit was found.

 

Keywords: beam, damage detection, vibration, natural frequencies, deflection

Cuvinte cheie: grindă, detectarea defectelor, vibraţii, frecvenţe proprii, săgeată

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32-57 DESPRE MODIFICAREA FRECVENŢELOR NATURALE ALE GRINZILOR DATORITĂ COROZIUNII

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Emilian STANCIU Gilbert Rainer GILLICH Zeno-Iosif PRAISACH la de

ON THE NATURAL FREQUENCY CHANGES OF

BEAMS DUE TO CORROSION

 

This paper presents a relation to be used for deriving the effect of mass loss on the natural frequencies of beams. Herein the stiffness decrease is not considered, since its effect on the natural frequencies is well-known. Consequently, the beam was considered with a constant cross-section but with reduced volumetric mass density in the corroded region. By this approach, we have first analytically studied the beam dynamics from an energetic point of view and contrived the mathematical relation. Afterwards, this relation was successfully tested against FEM simulations.

 

Keywords: beam, corrosion, vibration, natural frequencies, mode shape

Cuvinte cheie: grindă, coroziune, vibraţii, frecvenţe naturale, formă modală

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32-56 OPTIMIZAREA TOPOLOGICĂ A STRUCTURILOR ÎN INGINERIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandra-Daniela SCURTU Ancuţa Nadia JURCO Horea-George CRIȘAN Iacob-Liviu SCURTU la de

TOPOLOGICAL OPTIMIZATION OF THE STRUCTURE IN ENGINEERING

 

Nowadays the rapid development of the industry required use the optimization method. First part of this study shows the structural optimization method used in mechanical enginnering, being made a detailed explanation of the iterative optimization process. In the second part of the paper is presented the CAD modelling and the topological optimization of the holder used in mechanical engineering. the results of the optmization study and the conclusions are presented at the end of this paper.

 

Keywords: topological optimization, finite element analysis, objective functions

Cuvinte cheie: optimizare topologică, analiza cu elemente finite, funcții obiectiv

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32-55 SIMULAREA NUMERICĂ A UNEI VANE DE ECLUZĂ DE LA HIDROCENTRALA PORȚILE DE FIER I

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ioan LAZA Paul-Dan OPRIȘA-STĂNESCU Tiberiu Dimitrie BABEU la de

NUMERICAL ANALYSIS OF A LOCK VALVE

OF IRON GATE I HYDRO

 

One of the valves of the intermediate head of the lock of Iron Gate I Hydroelectric Power Station was damaged; it was replaced by another version. In order to elucidate the cause of the damage was done a numerical simulation using ANSYS Fluent software. The simulation has required the modeling of parts of channel for filling/emptying of the lock, taking also into account the hydrostatic water pressure, not just those static or dynamic. The paper presents a modeling of steady flow through the valve which is in a certain position, which shows velocity and pressure fields and the forces on the faces of the valve.

 

Keywords: lock, water navigation, valve, Iron Gate I Hydroelectric Power Station, numerical analysis, ANSYS Fluent

Cuvinte cheie: ecluză, vană, hidrocentrala Porțile de Fier I, simulare numerică, ANSYS Fluent

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32-54 METODĂ HIBRIDĂ DE STUDIU PENTRU ORICE TIP DE SECȚIUNE SUPUSĂ LA TORSIUNE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Ghiţă BÂRSAN Vasile NĂSTĂSESCU la de

A HYBRID MeTHOD OF STUDY FOR ANY SECTION

TYPE UNDER TORSIONAL LOADING

 

This paper presents a methodology regarding the numerical analysis of any section type under torsion loading. This methodology is named a hybrid one, because it practically consist in using of the membrane analogy – an experimental method –  but the solving and result analysis are made by Finite Element Method (FEM). In the modelling of a structure, of a beam, applying of the torsion moment involves some difficulties especially regarding of the local stress concentration. By the methodology presented in this paper, the analysis of the shear stress field can be made with a great accuracy using FEM, without any experimental means. This methodology takes into account all the physical significations of the membrane analogy and all these are evaluated by FEM. That require of the pressure-effort ratio to be -2 is made by a thermal loading, cooling the membrane. By post-processing, the numerical result analysis can be quickly and easily made. The modelling presented in this paper can be used for any section type: whatever the shape, no matter if the section has one or more holes etc. By this methodology, the membrane analogy becomes more efficient, more versatile and more accessible for any section type.

 

Keywords: torsion, membrane analogy, finite elements

Cuvinte cheie: torsiune, analogia cu membrana, elemente finite

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32-53 ȘCOALA DE REZISTENȚA MATERIALELOR DIN UNIVERSITATEA POLITEHNICA DIN BUCUREȘTI

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Costică ATANASIU Nicolae ILIESCU la de

SCHOOL OF STRENGTH OF MATERIALS FROM POLYTECHNIC UNIVERSITY OF BUCHAREST

 

Strength of Materials School of the Polytechnic University of Bucharest has a history of nearly 150 years attested. The paper presents the steps taken by the Strength of Materials School, closely related to evolution University, personalities that contributed to the formation and development of this school, the laboratory created and its involvement in solving of problems in economy and priority directions in research.

The conclusions of the paper highlight the conditions in which it forms a school for it to persist and grow.

 

Keywords: strength of materials, stability of construction, engineering school, electrical strain gauge technique, vibrations

Cuvinte cheie: rezistenţa materialelor, stabilitatea construcţiilor, şcoală de inginerie, tensometrie electrică, vibraţii

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32-52 STUDIU DE CAZ ASUPRA TERMOIZOLAŢIILOR CLĂDIRILOR CU MATERIALE ORGANIC – NATURALE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Doru Cristian BRATU la de

CASE STUDY ON THERMAL INSULATION IN BUILDINGS WITH ORGANIC – NATURAL MATERIALS

 

Reducing energy consumption through the thermal insulation of buildings, including insulation using materials of organic-natural origin is a current concern of specialists. The paper analyses energy rehabilitation solutions with various materials of organic-natural origin, proving the efficiency of using low density thermo isolating materials, as well as the efficiency of using small amounts of renewable primary energy in the production of said materials.

 

Keywords: building, thermal insulation, energy consumption, material, organic, natural

Cuvinte cheie: clădire, izolaţie termică, consum energetic, material, organic, natural

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32-51 DESPRE COMPANIA HEIDELBERG CEMENT ROMÂNIA S.A.

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Nicolae FÂNTÂNARU la de

REGARDING THE COMPANY HEIDELBERG CEMENT ROMÂNIA S.A.

 

The document contains the presentation of the company Heidelberg Cement Romania S.A. and its activity for carrying out sustainable constructions. The company is present in our country since 1998, with investments of over 450 million Euro, holding the honorary title of „Supplier for the Royal House of Romania“.

 

               Key words: the company Heidelberg Cement Romania S.A., sustainable constructions

Cuvinte cheie : compania Heidelberg Cement România S.A., construcții durabile

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32-50 STUDII ȘI COMPARAȚII ALE MATERIALELOR HIDROIZOLATOARE DE PROTECȚIE A INFRASTRUCTURII

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Mihaela DUMITRAN la de

STUDIES AND COMPARISONS OF WATERPROOFING MATERIALS FOR INFRASTRUCTURE PROTECTION

 

This article mainly illustrates the current situation of dedicated infrastructure materials as well as the comparison of some of them. For the waterproofing system comparison, one of the multi-criteria analysis methods was used: the Global Utility Method. The proposed analysis scenarios were: bituminous waterproofing for a continuous foundation, HDPE waterproofing for a continuous foundation and waterproofing based on additives for concrete, for a continuous foundation. Our multi-criteria analysis was based on the following features of the technology execution process: price, life span and degree of difficulty.

 

Keywords: waterproofing, foundation, multi-criterial analysis,  global utility method

Cuvinte cheie: hidroizolații, fundație, analiza multicriterială, metoda utilități globale

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32-49 ANALIZA ALUNECĂRILOR DE TEREN PRIN METODE GEODEZO-TOPOGRAFICE ȘI MODELARE 3D

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Iulia Diana GLIGA Maria-Olivia MOLDOVAN la de

ANALYSIS OF LANDSLIDES THROUGH GEODETIC-TOPOGRAPHICAL METHODS AND 3D MODELING

 

The aim of the landslides study, located on the southern slope of the Cetățuie Hill (urban zone, Gruia neighbourhood, Cluj-Napoca City) is to create a geodetic-topographic plan and documentation that can be used specifically in planning and predicting erosion of slopes. In this study case was used the topographic documentation for hazard assessment of landslides. For the plan metrical and nivelitic surveying were used national geodetic network points of support supplemented with thickening points (due to work), in order to use them as starting and closing elements for determining the survey control In order to determine the points of land used for the survey network, a Pentax R – 322NX Total Station was used. Creating a 3D model from the data collected in the field was done using TopoLT and Surfer.

 

Keywords: landslides, planning and predicting erosion, topographic plan, 3D model

Cuvinte cheie: alunecări de teren, prevenirea eroziunii, plan topografic, model 3D

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32-48 ORGANIZAREA EFICIENTĂ A RESURSELOR UMANE ŞI MATERIALE PENTRU EFICIENTIZAREA UNUI PROCES DE CONSTRUCŢIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Dorina SUCALĂ Ilie-Nicolae SUCALĂ Mihaela DUMITRAN la de

EFFICIENT ORGANIZATION OF HUMAN AND

MATERIAL RESOURCES TO STREAMLINE

THE CONSTRUCTION PROCESS

 

Concern about duration in which a building can be achieve, has been and remains one of the main problems of any specialist in this sphere of activity. Conception, design and implementation of a project require a constant monitoring the parameters of prediction, planification and supervision way works. Company management can be considered a discipline with economic character because its purpose is increasing economic efficiency

 

Keywords: construction activities, work productivity, processes, efficiency

Cuvinte cheie: activități de construcții, productivitatea muncii, procesele, eficiența

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32-47 PRINCIPII ȘI SISTEME DE CERTIFICARE A CLĂDIRILOR ÎN CONTEXTUL DEZVOLTĂRII DURABILE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Daniela Lucia MANEA Iacob FLOREA la de

PRINCIPLES AND SYSTEMS CERTIFICATION OF BUILDINGS IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT

 

The problem of constructing energy-efficient buildings and sustainable is increasingly present in recent years because their owners want to reduce energy consumption, carbon footprint reduction and maintenance costs. Created for this purpose or systems of assessment and certification of buildings in the context of sustainable development. The paper deals with the main building certification systems that are based on multi-criteria evaluation methodology following: raising awareness of the beneficiaries, design, construction, operation and promotion of integrated design practices.

 

Keywords: sustainability development, environmental certification systems, energetic efficiency, environment, pollution, building, valuation method, climate change, interior comfort

Cuvinte cheie: dezvoltare durabilă, sisteme de certificare ambientală, eficiență energetică, mediu, poluare, construcții, metodă de evaluare, schimbare climatică, confort interior

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32-46 ANALIZA TENSIUNILOR DE TURNARE ÎNTR-O PIESĂ TIP REȚEA DE CONTRACȚIE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Marius Dan CRIȘAN Tiberiu LEHENE Vasile Filip SOPORAN la de

STRESS ANALYSIS OF CASTING IN A PART NETWORK TYPE CONTRACTION

 

This paper presents a study on how the occurrence and distribution of tensions casting a piece of „network contraction” or „yoke of contraction”. It makes a comparative analysis of the results provided by the aluminium alloy solidification simulation EN AC-Al Si7Mg0,3 cast in the mould of the classic mix of training and experimental results obtained by casting the play of the same alloy and in the same conditions and by cutting its determination tensions.

 

Keywords: thermal stress, aluminum alloy, castings

Cuvinte cheie: stres termic, aliaj de aluminiu, piese turnate

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32-45 MANUFACTURAREA ADITIVĂ – TEHNOLOGIE DE PERSPECTIVĂ ÎN PROCESAREA MATERIALELOR PRIN TURNARE

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Emil NAGY la de

ADDITIVES MANUFACTURING A TECHNOLOGICAL

FUTURE IN MATERIALS PROCESSING BY CASTING

 

Material processing by casting requires the use of various types of raw materials, numerous auxiliary materials, various forms of energy and technological fluids flowing through varied route in several specific types of plant and machinery. The changes that have occurred in industrial technologies for the past 20 years under the new paradigm „changing technologies under the influence of the economic, social and political” and left their mark on the field for obtaining substantial and parts by processing materials by casting. Recent decades have marked the appearance in the current industrial operation in the processing of materials, concerns more highly bound to reduce and optimize energy consumption and materials linked with improving the environment. This development has led to the widening, deepening and broadening the scope in order of the best processing methods to ensure the sustainable development as on real. As such materials processing moulding consider key issues related to the technological side and those on the economic side, but also those that are imposed by increasing quality and minimizing environmental impact. Exploring the use of additive manufacturing system based on fundamental data, analyses, measurement and experimental results the scope of this article. This analysis leads to the idea of perspective as moulding materials processing has the potential to become a driving force to achieve a sustainable society by introducing efficient production practices that contribute to a considerable decrease negative environmental impact.

 

Keywords: casting materials processing, technological, development, new procedures

Cuvinte cheie: materiale de turnare de prelucrare, tehnologice, dezvoltare, proceduri noi

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32-44 ANALIZA CHIMICĂ ȘI MICROSTRUCTURALĂ A MATERIALULUI UTILIZAT LA TURNAREA UNUI CLOPOT

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Gabriel BATIN George ARGHIR Liviu BRÂNDUŞAN la de

CHEMICAL AND MICROSTRUCTURAL ANALYSES OF

A MATERIAL USED TO CAST A BELL

 

The present study was setup to determine the chemical composition of a bell material. After 27 years of service, a bell weighting 200 kg was broken. Two solutions were proposed for the repairing: soldering using Ag (cheap, but affecting the sound quality and mechanical properties) and a melting the old bell and casting a new one (approximately 16 times more expensive, but with better properties).  An optical microscope Olympus GX51 was used to study the microstructure. The chemical composition was determined using an XRF device Olympus Delta Element. The analysis showed the presence of lead and tin in composition, close to the upper limits. The presence of lead and eutectic structure, and the porosity produced a large crack on the basis of the bell. Clusters of macro pores were observed near the surface of the bell.  The fatigue could appear on the base of this

 

Keywords: bronze, microstructure, bell material, chemical composition

Cuvinte cheie: bronz, microstructură, material de clopot, compoziție chimică

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32-43 DISPOZITIV DE RECTIFICAT SUPRAFEŢE ELICOIDALE LA SCULE AŞCHIETOARE ADAPTABIL PE MAŞINI DE RECTIFICAT PLAN CARE ARE LA BAZĂ O CUPLĂ CINEMATICĂ DE TIP ROLĂ-CILINDRU

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandru-Cătǎlin MICACIU Ioan-Gheorghe VUŞCAN la de

DEVICE FOR CUTTING TOOLS TO ADJUSTED HELICAL SURFACES OF MILLING CUTTERS TO ADAPT AT  PLANE GRINDING MACHINE WHICH iS BASED ON A COUPLING KINEMATIC ROLL- CYLINDER

 

The paper presents a device for cutting tools to adjusted helical surface of milling cutters to adapt at plane grinding machine.

 

Keywords: helical surfaces clearance tooling

Cuvinte cheie: suprafeţe elicoidale de degajare la scule

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32-24 PROIECTAREA UNEI SUPRAFEȚE POMICOLE DE PRUNI ÎN SISTEM SUPERINTENSIV

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Vlad-Mihai DINU la de

THE PLUM TREE SURFACE DESIGNING

IN A SUPER-INTENSIVE SYSTEM

 

This project presents some of the benefits of a super-intensive plum orchard, a way to access European funding for technology or equipment and steps to be followed for a productive establishment

 

Keywords: plum orchard, founding, technology, importance

Cuvinte cheie: livadă de pruni, finanțare europeană, tehnologie, importanţă

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32-42 DETERMINAREA STABILITĂŢII STATICE A CUPLEI CINEMATICE EXTERIOARE CILINDRU-CILINDRU

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Alexandru-Cătǎlin MICACIU la de

DETERMINATION OF KINEMATIC COUPLING

STATIC OUTER CYLINDER

 

Helicoidally cylindrical surfaces are used for releasing surfaces of cutting tools the paper present aspects about experimental research of the kinematic coupling using different loads and different contact angle between roll and cylinder using a special developed for generation of the helical surfaces

 

Keywords: helical motion, contact pressure, contact angle

Cuvinte cheie: mișcare elicoidală, presiunea de contact, unghi de contact

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