Arhive zilnice: iulie 10, 2016


30-18 CERCETĂRI EXPERIMENTALE DE EROZIUNE CAVITAŢIONALĂ PE UN OŢEL ALIAT DE ÎMBUNĂTĂŢIRE CU UN CONŢINUT DE 97,2 % FIER

CAVITATION EROSION EXPERIMENTAL RESEARCH ON AN
IMPROVEMENT ALLOY STEEL WITH 97.2% IRON CONTENT
This paper presents the cavitation erosion experimental research on an
improvement alloy steel. The chemical compositions, also the name of this steel,
were identified using a spectrometer. After this analysis, iron content was 97.2 %
and the name of this steel has been identified as 41Cr4. The results are in tabular,
by graphic, as well as images and macrostructures presented and compared.
Keywords: cavitation erosion, 97,2 % Fe, macrostructure
Cuvinte cheie: eroziune cavitaţională, 97,2 % Fe, macrostructura

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30-17 ANALIZA DEZVOLTĂRII PROCESĂRII MATERIALELOR PRIN TURNARE

THE DEVELOPMENT ANALYSIS OF THE CASTING
MATERIALS PROCESSING
In present casting become a very important domain of materials
processing in the engineering arena. Achieving casting usually require a
greater complexity to the design and material processing to ensure a structural
integrity. Specific procedures for processing materials were continuously
developed and have come to represent today’s modern and efficient
alternatives for obtaining materials and products development prospects and
future use special.
Recent decades have marked the emergence of the current industrial
exploitation in the processing of materials, preoccupations more intensely
related to the reduction and optimization of material and energy consumption
linked with improving the environment.
Keywords: casting materials processing, technological development,
new Procedures
Cuvinte cheie: turnarea materialelor de prelucrare, dezvoltare
tehnologică, noi proceduri

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30-16 CONTACTE ELECTRICE PENTRU CURENŢI INTENŞI PRODUSE PRIN METALURGIA PULBERILOR

ELECTRICAL CONTACTS FOR STRONG CURRENTS
MADE BY POWDER METALLURGY
It was tested to be produced electrical contacts for strong currents by
infiltration after sintering, because the final density is much higher (11.100
kg/m3) and porosity is much lower (10.85 %). The infiltration after sintering
variant contains the steps: powder mixture preparation (W – 52 mass % – 520 g,
Ni – 2 mass % – 20 g, Cu – 46 mass % – 460 g, zinc stearate – 0,7 mass % – 7
g), homogenization, pressing (4.5 MPa), sintering (730 and 780 oC) and
infiltration (the green part is layed down on an electrocorindon EC 120 bed,
then the Cu green is on top of it, 1100 oC). In this variant the green part density
is almost constant (s = 0.062), with an identical porosity of the first after the end
of the process (14,28 %). By infiltration the density increased drastically (at
10,832 kg/m3), but its variations were increased also (s = 0.174) and porosity
decreased (at 10.85 %). The attained density is not sufficient for electrical
contacts work (11,100 kg/m3), but it is closer. The final composition of the
electrical contact was: W – 48.69 mass %, Ni – 1. 87 mass % and Cu – 49.44
mass %.
Keywords: sintered electrical contacts, W-Cu
Cuvinte cheie: contacte electrice sinterizate, W-Cu

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30-15 CERCETĂRI PRIVIND REABILITAREA PIESELOR PRIN ÎNCĂRCARE CU SUDURĂ

RESEARCH ON THE REHABILITATION OF PARTS
HARD SURFACING
The article presents a commonly used method for rehabilitation of parts
by welding load. The quality of rehabilitation is assessed by a set of
characteristics that give the reconditioned piece, the ability to meet the
necessary requirements, operating under normal conditions. Welding
instructions through material loading, are applied to the achievement of Francis
rotors type, on two components 1.4317 (GX4CrNi13-4)/SR EN 10213-2 cast
steel. These steels are ideal in terms of use conditions, where wear resistance
is really important, such as on hydraulic turbine components.
Keywords: rehabilitation, arc welded parts, charging by welding
Cuvinte cheie: reabilitare, piese sudate cu arc electric, încărcare prin
sudare

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30-14 PARTICULARITĂŢILE STRUCTURII ÎMBINĂRILOR LA SUDAREA MULTISTRAT

CHARACTERISTICS OF THE JOINTS STRUCTURE
AT MULTIPASS WELDING
The paper investigates the particularities of the welded joints structure at
multiphase welding, showing that the structure and properties of these joints is
not only influenced by the thermal action itself, but also by the metallurgical
phenomena from the metal subjected to welding.
Keywords: welded joints, thermal cycle, seam multilayer, heat wave
Cuvinte cheie: îmbinări sudate, ciclul termic, cusătură multistrat, undă
termică

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30-13 OPTIMIZAREA ÎNCĂLZIRII UNOR OŢELURI DE CALITATE ÎN VEDEREA PRELUCRĂRII PLASTICE

HEATING OPTIMIZATION OF HIGH GRADE STEELS
FOR PLASTIC PROCESSING
The research aimed at finding solutions for the dissolution in the
structural matrix of steel and the improvement in deformability. The results
allowed the optimization of the technology by reducing the heating-up duration,
and by dissoluting and globulising the ferrite.
Keywords: plastic processing, steel, structure
Cuvinte cheie: prelucrare plastică, oţel, structură

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30-12 PRESSURE REGULATORS FOR HIGH PURITY APPLICATIONS

REGULATOARE DE PRESIUNE FOLOSITE ÎN APLICAȚII
DE MARE PURITATE
Funcția de bază a unui regulator de presiune este de a accepta un
gaz de înaltă presiune dintr-un cilindru sau conductă, și de a reduce presiunea
la un nivel sigur și potrivit pentru o anumită aplicație.
The basic function of a pressure regulator is to accept a high-pressure
gas from a cylinder or pipe, and reduce the pressure to a safe level and
suitable for a particular application.
Keywords: Regulators, high purity gases
Cuvinte cheie: Regulatori, gaze de înaltă puritate

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30-11 RAMPĂ MOBILĂ TELESCOPICĂ CU ACŢIONARE HIDRAULICĂ PENTRU ACCES ÎN INTERIORUL CLĂDIRILOR PARTEA II – INSTALAŢIILE HIDRAULICĂ ŞI ELECTRICĂ

TELESCOPIC MOBILE RAMP WITH HYDRAULIC DRIVE FOR
ACCESS INSIDE OF THE BUILDINGS
PART II – ELECTRIC AND HYDRAULIC ECQUIPMENTS
The paper presents a telescopic mobile ramp with hydraulic drive for
access on upper levels inside of the of buildings. In the paper, is shows the
structural component of equipment, the technical characteristics and, also, its
usefulness in the actions of the Romanian Gendarmerie in its missions to
ensure public order and security.
Keywords: portable ramp telescopic, mobile hydraulic, scale hydro,
hydro-mechanical equipment
Cuvinte cheie: rampă mobilă telescopică, echipament mobil, acţionare
hidraulică, scară hidraulică, echipament hidro-mecanic

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30-10 RAMPĂ MOBILĂ TELESCOPICĂ CU ACŢIONARE HIDRAULICĂ PENTRU ACCES ÎN INTERIORUL CLĂDIRILOR PARTEA I – CONCEPŢIA GENERALĂ A ECHIPAMENTULUI

TELESCOPIC MOBILE RAMP WITH HYDRAULIC DRIVE FOR
ACCESS INSIDE OF THE BUILDINGS
PART I – GENERAL CONCEPTION
The paper presents a telescopic mobile ramp with hydraulic drive for
access on upper levels inside of the of buildings. In the paper, is shows the
structural component of equipment, the technical characteristics and, also, its
usefulness in the actions of the Romanian Gendarmerie in its missions to
ensure public order and security.
Keywords: portable ramp telescopic, mobile hydraulic, scale hydro,
hydro-mechanical equipment
Cuvinte cheie: rampă mobilă telescopică, echipament mobil, acţionare
hidraulică, scară hidraulică, echipament hidro-mecanic

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30-09 REFLEXIA INTERNĂ A LUMINII MONOCROMATICE PE FILME SUPERFICIALE DEPUSE PE SUBSTRATURI SOLIDE

THE INTERNAL REFLECTION OF MONOCHROMATIC LIGHT
ON SUPERFICIAL FILMS ON SOLID SUBSTRATES
Internal partial or total reflection present similitude and differences with
external reflection depending on the incidence angle of the light. Total reflection
has a major theoretical importance because complex aspects concerning the
interaction between light and superficial film. Both the analysis of the
parameters that decide upon the type of reflection and the manner of
interaction of the light with superficial films allow correct interpretation of
experimental measurements. Internal attenuated total reflection is one method
of investigation “in situ” of superficial films illustrated in this paper.
Keywords: internal reflection, superficial film, angle limit penetration
depth
Cuvinte cheie: reflexie internă, film superficial, unghi limită, adâncime
de pătrundere

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30-08 PROIECTAREA UNUI SISTEM SOLAR FOTOVOLTAIC INSULAR, CU AJUTORUL UNUI SOFTWARE DEDICAT

DESIGN OF AN OFF-GRID PV SYSTEM WITH A
DEDICATED SOFTWARE
This work aims to design and simulate, using a dedicated software,
Sunny Design Web, an open source application provided by SMA SOLAR
TECHNOLOGY, an off-grid photovoltaic system meant to ensure an
independent, smart and comfortable energy supply with solar power for private
households. Using this application, the designing process of PV systems has
become more simple and accessible for non-specialist in the field too, opening
on this the path to produce clean energy and provide energy independence for
many private households.
Keywords: PV system, design and simulate, monitoring system,
energy production, Sunny Design Web
Cuvinte cheie: sistem solar fotovoltaic insular, proiectare și simulare,
sistem de monitorizare, producţie de energie, Sunny Design Web

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30-07 OPTIMIZAREA MASICĂ A UNUI CAPTATOR SOLAR PLAN

MASS OPTIMIZATION OF A FLAT PLATE SOLAR
COLLECTOR
Usually a flat plate solar collector is characterized by constructivefunctional
data, the mass of a solar collector is a constructive characteristic,
which influences more the assembling and transport costs. This paper presents
a method of optimizing the mass characteristics of a flat plate solar collector, by
using materials with low specific mass. As a result of this optimization a 17 kg
flat plate solar collector was realized, resulting in a weight reduction of
approximately 57 % compared to a common solar collector.
Keywords: solar collector plan, mass optimization, solar
Cuvinte cheie: captator solar plan, optimizare masică, energie solară

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30-06 PILĂ SOLARĂ FOTOVOLTAICĂ ÎN BAZA CONTACTULUI n-In As – GEL CE CONŢINE PERECHEA REDOX St2+/4+

CELL SOLAR PHOTOVOLTAIC ON THE CONTACT N -IN AS –
GEL CONTAINING PAIR REDOX ST2 + / 4 +
In the article descripted the possibilities of obtaining some spectral and
photoelectric properties of solar element based an photo electrochemical chain
(+) Cu-C-MnO2-Gel-n-InAs-Cu (-).
Keywords: converting photo electrochemical solar, solar cell
Cuvinte cheie: convertizor fotoelectrochimic pentru energia solară, pilă
solară

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30-05 DINAMICA MECANISMULUI CENTRIFUGAL DE PROTECȚIE LA SUPRATURARE A ROTORULUI DE TURBINĂ EOLIANĂ DE PUTERE MICĂ

DYNAMICS OF THE CENTRIFUGAL MECHANISM FOR
PROTECTION AT OVERSPEED OF THE LOW
POWER WIND ROTOR TURBINE
Rotor over speed protection for small wind turbine power requires a
mechanical system cheap and reliable as possible. This is because any electric
or electronic device depends on the electrical power source that disaster
becomes unavailable. Of these centrifugal mechanism is priced at acceptable
cost, but contains some subtleties of interpretation of the method of operation.
In this paper, we explain step by step the original solution of this mechanism
put in place for a 5 kW wind turbine.
After triggering centrifugal mechanism speed is reduced to 20 … 30
rev / min and the effect of centrifugal mechanism is greatly reduced. So that the
force of compressed spring plus aerodynamic torque blade in relation to spindle
axis, returns the mechanism to its original work position. For that to occur
slowly, return must be controlled by a hydraulic damper or a blockingunblocking
flag position for the rotor blades.
Adjusting ballast weight of centrifugal mechanism and the reliable
automatically operation of the whole system should be checked repetitively on
a trial endurance stand.
Keywords: wind turbine, force, torque, protection centrifugal
mechanism at over speed
Cuvinte cheie: turbină eoliană, forțe, momente, mecanism centrifugal,
protecţie la supraturare

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30-04 CINEMATICA MECANISMULUI CENTRIFUGAL DE PROTECȚIE LA SUPRATURARE A ROTORULUI DE TURBINĂ EOLIANĂ DE PUTERE MICĂ

KINEMATICS OF THE CENTRIFUGAL MECHANISM FOR
PROTECTION AT OVERSPEED OF THE LOW POWER WIND
ROTOR TURBINE
Rotor over speed protection for small wind turbine power requires a cheap
and reliable mechanical system as possible. This is because any electric or
electronic device depends on the electrical power source that becomes
unavailable in disaster conditions. Of these, centrifugal mechanism is priced at
acceptable cost, but contains some subtleties of interpretation of the operation
mod. In terms of kinematics, centrifugal mechanism is reduced to a crank and
connecting-rod assembly with sliding piece. This paper presents schematically
this mechanism and the elements that govern the movement of the sliding
piece: race, speed and acceleration.
The mechanism function is alternative to a crank angle range of α =
0°…45°. Sliding piece is operated offset from the sliding axis. The complexity
consists in the fact that each blade is attached to the single sliding piece
through a rod and a crank. Thus the three rotor blades rotate simultaneously by
the cumulated action of the centrifugal force that occurs due to the rotating
counterweights.
Keywords: wind turbine, slide race, speed, acceleration, crank and
connecting-rod assembly
Cuvinte cheie: turbină eoliană, cursa culisei, viteza, accelerația, mecanism
bielă-manivelă

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30-03 CONSIDERAŢII CONCEPTUALE PRIVIND STABILITATEA TERMICĂ A ÎNCĂPERILOR DE TIP BIROU ÎNCĂLZITE PRIN SISTEME DE PARDOSEA

CONCEPTUAL CONSIDERATIONS ON THERMAL
STABILITY OF OFFICE ACCOMMODATION TYPE OF
FLOOR HEATING SYSTEMS
The paper addressed some aspects of the thermal behavior of
dynamic type office premises heated by radiant elements of tire installation
systems integrated low exergy
Keywords: exergy, radiating elements, thermally floor, potentially
reducing, dynamic – adaptive
Cuvinte cheie: exergie, elemente radiante, pardosea termoactivă,
potenţial de reducere, dinamic-adaptiv

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30-02 CONTRIBUȚIA SURSELOR REGENERABILE DE ENERGIE LA SECURITATEA ENERGETICĂ A REPUBLICII MOLDOVA

CONTRIBUTION TO RENEWABLE ENERGY SOURCES
ENERGY SECURITY OF MOLDOVA
Moldova’s energy sector represents a strategic branch of the national
economy. The level of development of this sector essentially determines
macroeconomic stability and energy security of the country and the success of
strategies and programs to achieve national economy.
Keywords: energy, energy security, forecasting, biomass, hydropower,
solar energy, wind energy
Cuvinte cheie: energie, securitatea energetică, prognoză, biomasă,
energia hidraulică, energie solară, energie eoliană

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30-01 EFICIENŢĂ ENERGETICĂ, DEZVOLTARE ŞI EDUCAŢIE – AJUTOR FRĂŢESC ŞI NECONDIŢIONAT DIN PARTEA ROMÂNIEI

ENERGY EFFICIENCY, DEVELOPMENT AND EDUCATION –
UNCONDITIONAL AND BROTHERLY HELP FROM ROMANIA
The increase in the cost of energy resources, the advanced
depreciation of the buildings, the degradation of the environmental quality and
the Moldova’s total dependence on the external energy markets, are essentially
the key arguments which require the promotion of some consistent national
policies in the field of energy efficiency in all spheres of human activity. In this
context one area over which it can act with certainty is the field of buildings. In
this paper we try to highlight the contributions of Romanians citizens through
the Romanian Government to the development of education and increasing the
energy efficiency in buildings preschool, and directly the development of the
other bank of the Prut – Republic of Moldova.
Keywords: Romania, energy efficiency, development, education
Cuvinte cheie: România, eficienţă energetică, dezvoltare, educaţie

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29-96 INGINERUL ALEXANDRE GUSTAVE EIFFEL (1832 – 1923) Partea a II-a

L’INGENIEUR ALEXANDRE GUSTAVE EIFFEL
(1832-1923) Partie II
Cet article présente, synthétiquement, les principaux repères de la vie
et l’activité de l’ingénieur français Alexandre Gustave Eiffel, réalisateur d’une
série de structures métalliques audacieuses – ponts, viaducs, édifices – qui ont
fait sa célébrité en France et dans le monde. Auteur d’une laborieuse activité
scientifique expérimentale – étant considéré comme un des fondateurs de
l’aérodynamique – et entrepreneuriale, A. G. Eiffel est aussi le constructeur de
la Tour qui porte son nom – devenu le symbole représentatif de Paris. Cette
Tour a joué un rôle essentiel pendant la première guerre mondiale, aux débuts
de la télégraphie sans fil et, ensuite, de la télévision. Ses remarquables
accomplissements, légués en héritage à l’humanité toute entière, sont dignes
de notre profonde reconnaissance.
Mots-clés: structures métalliques, ponts, viaducs, édifices,
aérodynamique, soufflerie, contraintes, flèche, hélice, projectiles, tour
Cuvinte cheie: structuri metalice, poduri, viaducte, clădiri,
aerodinamica, restricții de tunel de vânt, săgeată, spirală, proiectile, turn

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29-95 INGINERUL ALEXANDRE GUSTAVE EIFFEL (1832 – 1923) Partea I-a

L’INGENIEUR ALEXANDRE GUSTAVE EIFFEL
(1832-1923) Partie I
Cet article présente, synthétiquement, les principaux repères de la vie
et l’activité de l’ingénieur français Alexandre Gustave Eiffel, réalisateur d’une
série de structures métalliques audacieuses – ponts, viaducs, édifices – qui ont
fait sa célébrité en France et dans le monde. Auteur d’une laborieuse activité
scientifique expérimentale – étant considéré comme un des fondateurs de
l’aérodynamique – et entrepreneuriale, A. G. Eiffel est aussi le constructeur de
la Tour qui porte son nom – devenu le symbole représentatif de Paris. Cette
Tour a joué un rôle essentiel pendant la première guerre mondiale, aux débuts
de la télégraphie sans fil et, ensuite, de la télévision. Ses remarquables
accomplissements, légués en héritage à l’humanité toute entière, sont dignes
de notre profonde reconnaissance.
Mots-clés: structures métalliques, ponts, viaducs, édifices,
aérodynamique, soufflerie, contraintes, flèche, hélice, projectiles, tour
Cuvinte cheie: structuri metalice, poduri, viaducte, clădiri,
aerodinamica, restricții de tunel de vânt, săgeată, spirală, proiectile, turn

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29-94 NICOLAI COPERNIC – PĂRINTELE ASTRONOMIEI MODERNE (TORUŃ, 1473 – FROMBORK, 1543). Partea a II-a

NICOLAI COPERNIC – LE PÈRE DE L’ASTRONOMIE
MODERNE
On présente synthétiquement les principaux repères biographiques de
la fructueuse activité de Nicolas Copernic, à commencer par ses années de
formation – à l’école et aux universités fréquentées (Cracovie, Bologne, Padoue
et Ferrare) – et en continuant avec son travail de secrétaire et médecin
personnel de l’évêque Varmien, Lukas Watzelrode – son oncle -, ainsi qu’en
tant que chanoine de la Varmie et de la Poméranie. On met en évidence la
passion pour les mathématiques et l’astronomie du jeune étudiant et, plus tard,
sa ténacité à observer le ciel, ainsi que la persévérance de ses réflexions sur la
structure réelle de l’Univers.
Par crainte de la réaction de l’Église – qui était adepte du système
ptolémaïque, géocentrique – son ouvrage capital, «De revolutionibus Orbium
Caelestium», n’a été imprimé que dans l’année de sa mort, le système
ptolémaïque, héliocentrique s’avérant être réel, produisant ainsi une véritable
révolution en astronomie, en philosophie et en toute une série d’autres
sciences. On dit qu’il a été l’homme qui «arrêta le Soleil et qui mit la Terre en
marche»!
Mots-clés: Université, astronomie, univers, Terre, Soleil, planètes,
géocentrique, héliocentrique, cosmos
Cuvinte cheie: universalitate, astronomie, Pământ, Soare, planete,
univers, geocentric, heliocentric, cosmos

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29-93 NICOLAI COPERNIC – PĂRINTELE ASTRONOMIEI MODERNE (TORUŃ, 1473 – FROMBORK, 1543). Partea I-a

NICOLAI COPERNIC – LE PÈRE DE L’ASTRONOMIE
MODERNE
On présente synthétiquement les principaux repères biographiques de
la fructueuse activité de Nicolas Copernic, à commencer par ses années de
formation – à l’école et aux universités fréquentées (Cracovie, Bologne, Padoue
et Ferrare) – et en continuant avec son travail de secrétaire et médecin
personnel de l’évêque Varmien, Lukas Watzelrode – son oncle -, ainsi qu’en
tant que chanoine de la Varmie et de la Poméranie. On met en évidence la
passion pour les mathématiques et l’astronomie du jeune étudiant et, plus tard,
sa ténacité à observer le ciel, ainsi que la persévérance de ses réflexions sur la
structure réelle de l’Univers.
Par crainte de la réaction de l’Église – qui était adepte du système
ptolémaïque, géocentrique – son ouvrage capital, «De revolutionibus Orbium
Caelestium», n’a été imprimé que dans l’année de sa mort, le système
ptolémaïque, héliocentrique s’avérant être réel, produisant ainsi une véritable
révolution en astronomie, en philosophie et en toute une série d’autres
sciences. On dit qu’il a été l’homme qui «arrêta le Soleil et qui mit la Terre en
marche»!
Mots-clés: Université, astronomie, univers, Terre, Soleil, planètes,
géocentrique, héliocentrique, cosmos
Cuvinte cheie: universalitate, astronomie, Pământ, Soare, planete,
univers, geocentric, heliocentric, cosmos

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29-92 SISTEM AUTOMAT PENTRU ÎNCERCAREA LA TRACȚIUNE A PRODUSELOR COMPOZITE DIN CAUCIUC

SYSTEME AUTOMATISE POUR L’ESSAI
DES PRODUITS COMPOSITES EN CAOUTCHOUC
On pressente une solution pour moderniser une installation d’essai des
produits en caoutchouc [8], [9].La modernisation réside essentiellement dans le
remplacement des traducteurs de force de type inductif par des cellules de
traction plus précise (cellules dynamométriques), qui offre la possibilité d’avoir
une précision plus élevée du mesurage, de renoncer aux solutions mécaniques
pour mettre en évidence la déformation de la pièce et de les remplacer avec
des règles optiques, plus précises et plus facile d’intégrer dans un système
automatisé
Mots cles: system automate, essai de produits, produits composites
Cuvinte cheie: sistem automat, încercarea produselor, produse
compozite

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29-91 CONSIDERAȚII PRIVIND INFLUENȚA VIBRAȚIILOR ALEATOARE INDUSE DE VEHICULE ȘI CALEA DE RULARE ORGANISMULUI UMAN

CONSIDERATIONS REGARDING THE INFLUENCE OF
RANDOM VIBRATIONS INDUCED BY VEHICLES
AND HUMAN BODY RACEWAY
The Comfortability of modern vehicles is one of the most important
attributes that each of buyers who want the highest possible level, increasingly
more. Comfort depends on a number of external factors (raceway, damping
system, insulation/soundproofing) and internal (air conditioning system, interior
space, comfortability seats).
Isolation of vibration of the rails and vehicle body structure is the most
important aspect in reducing the destructive effects of the spine – the main area
affected, and the degradation of the muscular system, nervous, on the go. Seat
level vibration perception is different from the front to the rear because of the
different construction and equipment.
Keywords: random vibration, body, magnetorheological damper
Cuvinte cheie: vibrații aleatoare, organismul uman, amortizor
magnetoreologic

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29-90 ANALIZA TENSIUNILOR ȘI DEFORMAȚIILOR LA ȘASIUL UNUI VAGON DE MARFĂ CU PEREȚI ÎNALȚI ÎN URMA UNOR LUCRĂRI DE REPARAȚIE ȘI CONSOLIDARE

ANALYSIS OF TENSIONS AND DEFORMATIONS TO THE
CHASSIS OF A FREIGHT WAGON WITH HIGH WALLS
AFTER CONSOLIDATION AND REPAIR WORKS
This paper checks by the finite element method the solution to
strengthen the chassis of a boxcar with high walls in the process of corrective
and predictive maintenance railway vehicles run scheduled ungass works
inspections and repairs in order to keep running optimally or improved and
increase transport capacity correlated with the life extension of the rail vehicle
Keywords: freight wagon loads, stresses, strains, maintenance
Cuvinte cheie: vagoane de marfă, sarcini, tensiuni, deformaţii,
mentenanţă

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29-89 TENSIUNI REMANENTE ȘI METODE DE DETENSIONARE A CADRELOR BOGHIURILOR VAGOANELOR DE CĂLĂTORI

RESIDUAL STRESS AND METHODS OF STRESS RELIEF
FOR COACHES BOGIE FRAMES
The study has pursued experimental determination of residual
stresses in the bogie Minden-Deutz that equips coaches Series 209, the
efficiency of the applied stress relieving treatment and the possibility to shift
towards the dimensional stabilization through vibrations.
Keywords: residual stress, bogie
Cuvinte cheie: tensiuni remanente, boghiu

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29-88 LUCRUL CU PROGRAMUL SOLIDWORKS PENTRU CALCULUL FRECVENŢEI PROPRII A UNUI CUB UTILIZÂND STUDIUL DE TIP „FRECVENŢĂ”

WORKING WITH SOLIDWORKS SOFTWARE FOR THE
CALCULATION OF NATURAL FREQUENCY OF A CUBE
USING THE „FREQUENCY” TYPE STUDY
This paper presents the work with SolidWorks software regarding the
Simulation module respectively the „Frequency” type study. This type of study will
highlight the calculation and results for the natural frequency of vibration modes for
a cube with the side of 50 mm. To see how the natural frequency values can be
change, different geometries of the same designed 3D cube will be make.
Keywords: SolidWorks software, study, natural frequencies, cube
Cuvinte cheie: programul SolidWorks, studiu, frecvenţe proprii, cub

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29-87 INFLUENȚA RIGIDITĂȚII MECANICE ASUPRA FRECVENȚELOR PROPRII DE VIBRAȚIE A CADRELOR METALICE

THE INFLUENCE OF MECHANICAL STIFFNESS ON EIGEN
FREQUENCIES OF VIBRATION AT METAL FRAMES
This paper presents a study regarding the changes of the natural
frequency of trusses due to stiffness increase. The finite element analysis was
performed, considering a constantly increasing of stiffness of frame. In this way,
the correlation between frequency changes in the transversal vibration modes
and stiffness for the studied frames is highlighted.
Keywords: stiffness, eigen frequency, vibration mode, FEM
Cuvinte cheie: rigiditate, frecvente proprii, moduri de vibraţie, MEF

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29-86 METODE DE EVIDENŢIERE A FRECVENŢELOR APROPIATE

METHODS TO HIGHLIGTH CLOSE FREQUENCY
This paper offers an overview of simpler methods to accurately
estimate frequencies. In standard signal processing, the precision of frequency
estimation increases once the frequency resolution is improved. A finer
resolution is achieved by increasing the observation time interval. If this cannot
be done, the signal length can be artificially extended through the so-called
”zero-padding” method, by adding a number of samples with null amplitude.
The methods have been tested for concrete cases, using the signal processing
tool offered by the open source software, Scilab.
Keywords: signal processing, spectral analyze, “zero-padding” method,
Scilab environment
Cuvinte cheie: procesarea semnalelor, analiza spectrală, metoda
“zero-padding”, mediul Scilab

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29-85 DIMINUAREA DEFECTELOR CE APAR ÎN PROCESUL DE FABRICAȚIE AL ROLELOR DE RULMENT

SHRINKING FAILURE OCCURRING MANUFACTURING
PROCESS OF ROLLER BEARINGS
This paper contains a brief overview of the flow of production of roller
bearings that equip radial model practiced by the firm INA/Germany. The focus
is on defects occurring in different phases that are unusable respective rolls. Is
a case study and propose a method of reducing the defects reported
Keywords: radial roller bearing, INA/Germany, polishing process
Cuvinte cheie: rulment radial cu role, INA/Germania, procedeu de
lustruire

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29-84 DEFECTE SEMNALATE LA LAGĂRELE DE ROSTOGOLIRE ÎN TIMPUL EXPLOATĂRII

FAULTS REPORTED TO CAMPS ROLLING IN SERVICE
This paper contains a brief overview of defects occurring in rolling
bearings during operation. Currently, design and manufacture various types of
bearings concerned several production units worldwide. The first three
prestigious companies in Europe are: SKF / Sweden, SNR / France and INA /
Germany. Replacing sliding bearings with roller bearings is made in the context
of the cruising speeds of vehicles grow continuously and need that from stage
design to ensure maximum safety during operation thereof by eliminating
possible defects that can occur.
Keywords: bearing, faulty operation, prestigious companies
Cuvinte cheie: rulment, defecte în exploatare, firme de prestigiu

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29-83 STUDIUL STĂRII DE TENSIUNI ŞI DEFORMAŢII CE APAR ÎN ROLELE DE RULMENT DE DIMENSIUNI MICI ÎN TIMPUL CONTACTULUI DINTRE CAPUL ROLEI ŞI GENERATOARE CÂND UNGHIUL DE IMPACT ESTE CUPRINS ÎNTRE 0° ÷ 60°

THE STUDY OF STRESS AND STRAIN OCCURRING IN
SMALL BEARING WHEELS DURING THE CONTACT
BETWEEN THE HEAD PULLEYS AND GENERATING THE
ANGLE OF IMPACT IS BETWEEN 0° ÷ 60°
The paper presents comparative way using numerical techniques for
modeling dynamic physical phenomena occurring at impact between two rolls
with a diameter of 16 mm in several distinct situations to clash head –
generating at an angle to an angle between 0° ÷ 60°. Analyzed situations occur
frequently in the manufacturing of cylindrical rollers that equip small radial
bearings.
Keywords: cylindrical roller, impact, stress, displacement
Cuvinte cheie: rolă cilindrică, impact, tensiuni, deformaţii

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29-82 STUDIUL CIOCNIRII ROLELOR DE RULMENT RADIAL PRIN METODE NUMERICE DE CALCUL

BALL BEARINGS RADIAL COLLISION STUDY
BY NUMERICAL CALCULATION
The paper shows that the wheels now fitted radial bearings collide
during the manufacturing process. As a result of this rolls surface defects occur
due to collision elastic-plastic material. For different cases of collision was
made a study on the state of stresses and strains using the Finite Element
Method.
Keywords: radial roller bearing, Elastoplast’s clash, finite element
method
Cuvinte cheie: rulment radial cu role, ciocnire elasto-plastică, metoda
elementelor finite

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29-81 REZULTATE PRELIMINARE PRIVIND STABILIREA EXPERIMENTALĂ A MĂRIMII COEFICIENTULUI DE FRECARE LA ROSTOGOLIRE

PRELIMINARY RESULTS CONCERNING ON EXPERIMENTAL
DETERMINATION OF THE ROLLING FRICTION COEFFICIENT
The authors, in their preliminary investigations [xxxx], conceived an
original testing bench, in order to establish the magnitude of the rolling friction
coefficient.
Involving the mentioned testing bench, the authors started to perform
some preliminary experimental investigations in several tribo-couples, foreseen
with thin plastic cover layer.
In the described investigations, the authors offer useful correlations
between the thickness of the layers and the magnitude of the rolling friction
coefficient.
Their next topic will consist in combining different tribo-couples, having
covered and uncovered elements, in order to diminish as soon as possible the
magnitude of the rolling friction coefficient.
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 rolling friction coefficient, corresponding to different pairs of elements, which
constitute the tribo-couple.
Keywords: rolling friction coefficient, experimental evaluation, original
testing bench
Cuvinte cheie: coeficient de frecare la rostogolire, investigaţii
experimentale, stand original pentru teste

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29-80 CONSIDERAȚII PRIVIND REZISTENŢA LA IMPACT A PARAPETULUI DE PROTECȚIE FĂRĂ ELEMENT DE AMORTIZARE

IMPACT RESISTANCE CONSIDERATIONS OF ROAD
RESTRAINT SYSTEMS WITHOUT DAMPING ELEMENTS
The paper presents the results of experiment made using a pendulum
for road restraint systems without damping elements. Deformable parapets are
created to protect the vehicles and other participants at traffic from danger and
serious injury.
The results of the experiment are very important for the knowledge of
the type of parapets that are being used on the roads.
Keywords: shock test, road restraint systems
Cuvinte cheie: încercare la şoc, sisteme de reținere rutiere

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29-79 TESTE DE ÎNCOVOIERE ASUPRA SANDWICH-ULUI COMPOZIT DE TIP CELLITE

BEND TESTS ON CELLITE COMPOSITE SANDWICH
In this paper, three-point bend tests have been accomplished on
CELLITE composite sandwich to determine the flexural properties of this kind of
structure. Load-deflection distributions until break and at 50 mm deflection have
been carried out on a LR5K PLUS Lloyd’s Instruments materials testing
machine using the NEXYGEN PLUS software.
Keywords: test bending, composite sandwich, Cellite, load-strain
distributions
Cuvinte cheie: test încovoiere, sandwich compozit, fibră celit, distribuţii
forţă-deformaţie

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29-77 INFLUENŢA DEFECTULUI ASUPRA MODIFICĂRII TEMPERATURII CRITICE LA FLAMB

DAMAGE INFLUENCE ON THE CRITICAL BUCKLING
TEMPERATURE
This paper presents the influence of a transverse damage in a doubleclamped
beam upon the critical buckling temperature. First, the buckling
temperatures and subsequent loads are analytically investigated on an intact
prismatic beam, together with the dynamic behavior in terms of the natural
frequencies. Afterwards, the effect of a transverse damage is considered, and a
relation expressing the frequency alteration due to the crack is provided. To
prove the relation’s validity a finite element analysis was performed for some
particular cases, and the results compared with those obtained analytically. The
investigation did show a good concordance between the results obtained in the
two ways, proving the correctness of the analytical approach.
Keywords: double-clamped beam, damage, thermal buckling
Cuvinte cheie: grindă dublu încastrată, defect, flambaj, temperatură
critică

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29-76 INFLUENTA INTERFEȚEI ȘARJĂ/MATRICE ASUPRA PROPRIETĂȚILOR MECANICE ALE MATERIALELOR COMPOZITE

INFLUENCE OF INTERFACE BATCH/MATRIX COMPOSITE
MATERIALS ON MECHANICAL PROPERTIES
The objective of this article is to present the means used for
experimental characterization of materials studied, the manufacturing process of
composite materials, specimen’s preparation test for metal surfaces required for
imaging by electron microscopy, and behavior analyzing interface/matrix.
Keywords: composite materials, resins, kaolin
Cuvinte cheie: materiale compozite, rășini, caolin

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29-75 STUDIUL CURGERII ÎN REZERVOARE PREVĂZUTE CU ORIFICII ASIMETRICE

THE FLOW STUDY IN TANKS EQUIPED WITH
ASIMETRIC ORIFICES
This paper presents numerical results referring at the hydrodynamic
spectre of the flow inside a tank with asymmetric orifices. The finite difference
method is used to integrate the Navier-Stokes equations. Besides the
characteristics of the flow inside the tank, it presents interest the determination
of the contraction coefficient of the orifices.
Keywords: hydrodynamic spectrum, numerical methods, contraction
coefficient, orifice
Cuvinte cheie: spectru hidrodinamic, metode numerice, coeficient de
contracție, orificiu

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29-74 ENEGIA DE DEFORMARE DIN DISCUL BIPLAN AL VANEI FLUTURE

STRAIN ENERGY IN A BUTTERFLY VALVE BIPLAN DISK
The papers present the strain energy that appears in a biplane disc of
the butterfly valve by using the numerical methods. Due to the eccentricities of
the biplane butterfly disc the obtained stresses and displacements are not
uniform in the whole structure of the disc. The study of the strain energy allows
us a qualitative evaluation of the energy distribution in the biplane disc when
external loads act on the upstream side of the disc.
Keywords: deformation energy, biplane butterfly valve disc, stresses,
strains
Cuvinte cheie: energie de deformare, disc biplan vană fluture, tensiuni,
deformaţii

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29-73 SUPRAFEŢE NEUTRE PENTRU DISCULUI BIPLAN AL VANEI FLUTURE

NEUTRAL SURFACES FOR BUTTERFLY VALVE BIPLAN DISK
Due to the eccentricities of the biplane disc of the butterfly valve, the
analysis of the directional stresses can be done by using the numerical
methods. The paper presents the neutral surfaces of butterfly valve biplane disc
obtained by numerical methods. The neutral surfaces are defined as surfaces
with directional stress of zero value or, those surfaces which delimit the passing
of the directional stresses from negative values to positive values.
Keywords: neutral surfaces, butterfly valve disc, tensions
Cuvinte cheie: suprafeţe neutre, disc vană fluture, tensiuni

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29-72 RECONSTITUIREA GEOMETRIEI COMPONENTELOR MECANICE PRIN FOTOGRAMETRIE PARTEA A II-A

3D RECONSTRUCTION OF THE MECHANICAL PARTS
GEOMETRY THROUGH PHOTOGRAMMETRY – PART II
The paper has the following objectives: to describe the
Photogrammetry technique, to present its principles and results, to review
photogrammetry software and to exemplify some applications in the field of
mechanical parts that were made with said software.
Keywords: photogrammetry, part, mechanical
Cuvinte cheie: fotogrametrie, componente, mecanice

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29-71 RECONSTITUIREA GEOMETRIEI COMPONENTELOR MECANICE PRIN FOTOGRAMETRIE PARTEA I

3D RECONSTRUCTION OF THE MECHANICAL PARTS
GEOMETRY THROUGH PHOTOGRAMMETRY – PART I
The paper has the following objectives: to describe the
Photogrammetry technique, to present its principles and results, to review
photogrammetry software and to exemplify some applications in the field of
mechanical parts that were made with said software.
Keywords: photogrammetry, part, mechanical
Cuvinte cheie: fotogrametrie, componente, mecanice

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29-70 METODA SPH ÎN PROBLEME HIDROTEHNICE

SPH METHOD IN HYDRAULIC PROBLEMS
Smoothed Particle Hydrodynamics (SPH) method is a meshless
numerical method, which has many advantages comparatively with Finite
Element Method (FEM), regarding those problems where large displacement,
strong nonlinearities or deformations with high strain rates occur (high velocity
impact problems, air or underwater explosion calculus etc.). As fluid mechanics
is concerned, this method is practically completely validated. Some very difficult
problems, like fluid-structure interaction (FSI), free surface evolution of a fluid
and others, can be easier solved by SPH method. In our country this numerical
method is practically unused and even unknown. This paper comes firstly with
theoretical fundamentals of the SPH method, after that an hypothetical
hydraulic problem is solved. It is about the numerical modeling of a gate which
controls the fluid level between two enclosed spaces. In addition to urging the
use of SPH method, this paper presents an available numerical model, based
on this method, for many others similar problems and useful conclusions.
Keywords: free particles, SPH, Navier -Stokes, flowing, fluid
Cuvinte cheie: particule libere, SPH, ecuaţiile Navier-Stokes, curgere,
fluid

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29-69 UNELE ASPECTE PRIVIND CURGEREA GAZELOR PRIN ŢEVILE LUNGI

SOME ASPECTS OF THE FLOW OF GAS BY LONG PIPES
This paper deals with studying the evolution of gas dynamics
parameters in long pipes. This study is applicable to the design and
construction of special pipes.
Keywords: gas dynamics parameters, enthalpy, perfect gas, Mach
criterion, long pipe, Reynolds criterion
Cuvinte cheie: parametric gazodinamici, entalpie, gaz perfect, criteriul
Mach, ţeavă lungă, criteriul Reynolds

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29-68 CONSIDERAŢII PRIVIND FACTORII CARE DETERMINĂ REZISTENŢA LA ÎNAINARE A CORPURILOR AERODINAMICE ÎN FLUID INCOMPRESIBIL

CONSIDERATIONS FACTORS DETERMINING RESISTANCE
IN SPEED ÎNAINARE BODIES INCOMPRESSIBLE FLUID
This paper addresses issues concerning the influence on friction and
detachment aerodynamic drag bodies in incompressible fluid. The results of
investigations contribute to a more rigorous calculation of flight trajectories of
projectiles and missiles.
Keywords: rocket, projectile, flight path, speed gradient, fluctuations,
similar speeds, aerodynamic force
Cuvinte cheie: rachetă, proiectil, traiectorie de zbor, gradient de viteză,
fluctuaţii, profil de viteze, forţă aerodinamică

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29-67 O ÎNCERCARE DE OBTURARE CU DOP DE GHEAŢĂ A UNUI TRONSON DE CONDUCTĂ ORIZONTALĂ (DN 300 mm) STRĂBĂTUT DE APĂ DEMINERALIZATĂ

A CONTROLLED ICE PLUG FORMING EXPERIMENT
CONDUCTED ON A HORIZONTAL PIPE SECTION (NPS 12)
WITH DEMINERALIZED WATER FLOWING THROUGH
In a hydraulic pipe-line installation, isolating a horizontal section
requires forming one or two ice plugs in a controlled process. This technique is
used for carrying out circuit maintenance or component replacements without
shutting down the entire installation. In both cases, the ice plug (or both ice
plugs) must be maintained until completing the repair activities. This paper
describes an experiment conducted on a horizontal NPS 12 horizontal pipe
section and its sequences, followed by the results and conclusions. The paper
is dedicated to specialists working in research and technological engineering.
Key words: cutting-off the flow, ice deposit, demineralised water,
hydraulic resistance
Cuvinte cheie: oprirea curgerii, depunere de gheaţă, apă
demineralizata, rezistenţa hidraulică

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29-66 MODELAREA SISTEMULUI DE RĂCIRE A ETANŞĂRILOR POMPELOR PRINCIPALE DIN CIRCUITUL PRIMAR DE TRANSPORT AL CĂLDURII LA CNE CERNAVODĂ

CNE CERNAVODA NUCLEAR POWER PLANT PRIMARY
HEAT TRANSPORT PUMPS GLAND SEAL
COOLING SYSTEM MODEL
Primary Heat Transport Pumps Gland Seal Cooling System scope is to
provide a high pressure D2O cooling flow to the primary heat transport pumps
seals. The system safety function is to maintain Primary Heat Transport System
pressure boundary integrity and to prevent radioactivity releases. In order to
monitor the seal operation and to warn of a possible malfunction or failure, the
papers propose an operation model, based on an electric-hydraulics similarity.
Keywords: pumps, gland seal, mathematical model, electric-hydraulics
similarity
Cuvinte cheie: pompe, presgarnitură, model matematic, similitudine
electric hidraulică

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29-65 EFECTELE DISPOZITIVELOR ELECTRONICE ASUPRA STRUCTURII ENERGETICE A FIINȚEI UMANE ȘI RELAȚIA DINTRE STRESUL CRESCUT ȘI PERFORMANȚA DIMINUATĂ

EFFECTS OF ELECTRONIC DEVICES UPON THE HUMAN
BEINGS ENERGETIC STRUCTURE AND THE POSSIBLE
RELATION BETWEEN INCREASED STRESS AND
DIMINISHED PERFORMANCE
This paper examines the effects which the use of electronic devices
may have upon the energetic body of the human being, measured with the
electro-photonic imaging device. The study offers a new perspective upon the
possible effects which may be caused by the use of electronic devices on the
human being. The study is a case study, and may, if considered appropriate,
lay the foundation for a long-term study including more subjects.
Keywords: electro-photonic imaging device, stress, energy, energetic
body
Cuvinte cheie: dispozitiv electro-fotonic, stres, energie, înveliș
energetic

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