Volume 1, No. 13 (2007)
Articles
THE SPRINGBACK BEHAVIOUR OF A U-SHAPED PARTMADE FROM TAILOR WELDED STRIPESFOR DIFFERENT WELDING LINE POSITION
ALBUŢ AURELIAN
This paper refers to some numerical simulation and experimental tests related to forming and springback of a U-shaped part manufactured from tailor welded stripes. Final shape of the formed part is seriously affected by springback effect. The materials tailored in the welded stripes have different springback values. This paper work is trying to prove out the important role of welding line position has on the springback phenomenon. The influence of the welding line position on the tailor welded stripes springback is examined using the simulation by finite element method (ABAQUS). Also, experimental tests have been carried out using different positions of the welding line and maintaining constant all other parameters. A comparison between simulation and experiment results is presented in the final section of this paper.
THE WELDING LINE DIRECTION INFLUENCE ON SPRINGBACK BEHAVIOUR OF A U-SHAPED PARTMADE FROM TAILOR WELDED STRIPES
ALBUŢ AURELIAN
This paper refers to some experimental tests concerning the formability and springback of a U-shaped part manufactured from tailor welded stripes. The final geometry of the obtained part is seriously affected by springback phenomenon. This paper work is trying to prove out the important role of welding line direction with respect to the forming force direction has on the springback phenomenon. The influence of the welding line orientation on the tailor welded stripes springback is examined during experimental tests using transversal and longitudinal welding line.
STUDIES REGARDING THE PROCURANCE OF THE LACTIC ACID THROUGH FERMENTATION
ARUŞ VASILICA ALISA, JINESCU GHEORGHIŢA, NISTOR DENISA, PIRCU NICOLETA
In this study one presents several modern methods for the procurement of the lactic acid. The lactic acid can be obtained through fermentation with selected bacteria using: corn flour, potatoes, molasses, and milk whey. The lactic acid resulting from this process of fermentation is afterwards recovered or extracted and the purified.
ANALYSIS BY SIMULATION OF THE INFLUENCE OF PROCESS PARAMETERS ON THE SPRINGBACK OF DEEP-DRAWN PARTS
AXINTE CRINA
The impact of process parameters on the springback intensity in the case of cylindrical deep-drawn parts is investigated. The study is focused on the influence of two parameters, respectively blankholder force and friction conditions, in order to assess the accuracy of the virtual obtained parts.
MANAGEMENT OF THE RECONSTRUCTION OF THE FOREST ECOSYSTEM (CASE STUDY BACAU COUNTY)
BERCA MIHAI, STOICA MARICICA
Massive deforestation of the last 15 years in the forest ecosystem of the county, the lack of interest of local authorities and owners for the up keep and exploitation of forests and scraps lead to the outbreak of a natural catastrophe and to the irreversible degradation of land, rivers and soil. The authors assess the current state of the forest ecosystem through the usual international indicators: size of the forest stock, its geographic distribution, composition of forests, accessibility and yield plan. The proposed measures for the reconstruction of the forest ecosystem aim at: ensuring the integrity and extension of areas with forest vegetation, ensuring stability and increased functional efficiency, preserving biodiversity, increasing the forest stock.
ASSESSMENT OF RISKS DUE TO METEOROLOGICAL PHENOMENA AND ANTROPIC ACTIVITIES IN THE TROTUS RIVER BASIN (CASE STUDY IN BACAU COUNTY)
BERCA MIHAI, STOICA MARICICA
Specialists of the International Institute for Climate Study have warned that year 2005 had been the warmest since the history of the thermometer on planet EARTH and had offered the most varied, extensive and numerous mass of events called “climatic catastrophes”, with the highest number of deceased and the greatest material losses. Year 2005 will not be “an exceptional one” at global level and by all means not in the Trotus River basin. There will be other years exceeding 2005 including Bacau County and the Trotus River basin.This is why an ecological reconstruction on the affected and assessed areas would be extremely costly and pointless, before the implementation of effective prognostic methods and of methods that would arrest and preserve the existing unaffected patrimony, a patrimony which could easily be affected by the climatic and antropic evolution of the coming years.Taking the current situation as a starting point (the data bases) and according to the project management, there is an absolute need to carry out “detailed analyses” of the evolution of climatic and antropic phenomena, in order to be able to prognosticate and establish the dimension of management measures to be implemented so as to CREATE A SUSTAINABLE AREA.
COMPARATIVE STUDY REGARDING THE COSTS OF USING CATEGORIES OF THE TAMPING TOOLS
BEŞLEAGĂ CR., DRAGOI D.D., BADEA S.G., STANCU M.
The objectives of modern construction, maintenance and repair technologies of railways demand among its important factors, a new solution for projecting, constructing and using of tamping tools. New types of tamping tools with increased durability which prove to be efficient during high productivity tamping processes should take the place of traditional tamping tools. It is needed by the new tamping tools, with adequate construction and geometry, adapted to the effective costs of the tamping operations, for the purpose to improve their durability and the efficacy.
THE PROBLEMS OF UTILIZATION OF THE METALLIC CARBIDES AT THE TAMPING TOOLS
BEŞLEAGĂ CR., DRAGOI D.D., BADEA S.G.
In the actual stage the main factor which has the primordial influence for the lastingness of the tamping tools is the wear of active part of these. It is necessary to concentrate the study and the research to find some ways, materials and technical processes for utilization of these, in the purpose of increasing the lastingness of active part of the tamping tools and the research of the behavior of these in exploitation. One example in this case is the usage of the hard materials like the plates of metallic carbides.
REDUCING OF DYNAMIC DEFLECTION OF SHAFTS FOR MIXING DEVICES BY OPTIMIZING THE DISTANCE BETWEEN SUPPORTS
BIBIRE LUMINIŢA, COBREA CODRIN
For improving of the design for vertical reactors with mixing devices, the establishing of optimal length between the supports of bearings is an important step in developing of operational parameters of these apparatus.Usually, for the shafts having a high rigidity, the distance between the bearings is bigger than for the elastic shafts having the same length.The clearance in bearings has an important influence on the optimal length of the distance between supports of bearings and on the absolute value of the deflection.Generally, the deviation l1,opt to small values is fewer dangerous than the deviation to high values.
THEORETICAL AND EXPERIMENTAL CONSIDERATIONS ON THE INFLUENCE OF THE AXIAL FORCE TO THE CRITICAL ROTATIONAL SPEED OF THE SHAFTS FOR MIXINGDEVICES
BIBIRE LUMINIŢA, COBREA CODRIN
The methods for theoretical analysis and for experimental analysis, separately used, are insufficiently to study the behavior under vibrations of the shafts of the mixing devices, because the computation in the fields of this kind of shafts, doesn`t only partially take into account the real static of loading.The paper shows some numerical values for the coefficient k, which introduces the effect of the axial force on the computation of the own real rotational speed, in the case of the propeller impellers and standard open type turbine impellers.
THEORETICAL RESEARCHES CONCERNING BENDING PROCESS OF THE PRESURIZED PIPES
BRADEA LUCIA
In this paper, the results of the theoretical researches concerning the variation of characteristics lines as a function of the constructive parameters (D - the outer diameter of pipe and h - the thickness of pipe wall) and mechanical parameters (?c), in the case of pressurized pipes bending process, are presented.
THE GENERAL CHARACTERISTIC CURVE OBTAINED IN THE CASE OF PRESSURED PIPES BENDING PROCESS
BRADEA LUCIA, AXINTE CRINA
The paper presents the characteristic curves obtained in the case of experimental researches concerning the pressured pipes bending process. These curves allowed the tracing of the general characteristic curves of process.
REENGINEERING AND QMS PREMISES OF DEVELOPMENT TO EXCELLENCE
BULATOVIC MIODRAG (1), DAŠIÆ PREDRAG (2)
"Theorists and practicients of quality sometimes ""forget"" basic object and subject of quality- BUYERS, dealing with different problems, as quality, causes and limits of quality improvement, combinations of standards etc.If we want to leave behind that situation, it is necessary to change behaviour of all business factors, or reengineering, according to processing model of quality system. If it results with buyer`s satisfaction, one of the basic conditions for business success is accomplished. In this paper, process reengineering is priority, as well as management re-engineering, project reengineering, all in function of quality."
A METHOD TO SOLVE HEAT TRANSFER PROBLEMS WITH A CHANGE OF PHASE
CĂLIMAN RADU, OLARU IONEL
"A method of broad applicability is presented which can be used to obtain solutions to problems involving a phase change. The solution in one of the phases is specified as a known single-phase solution; an inverse analysis then determines the solution for the other phase. Two problems are studied: The first yields the similarity solution for the planar geometry and the second gives the exact solution to a more general problem. Convergence is shown and error bounds are given. The method can accommodate convection, heat generation, variable properties, nonplanar, and multidimensional systems."
A THEORY OF ROTATING CONDENSATION
CĂLIMAN RADU, OLARU IONEL
An analysis is made for film condensation on a rotating disk situated in a large body of pure saturated vapor. The centrifugal field associated with the rotation sweeps the condensate outward along the disk surface, and gravity forces need not be involved. The problem is formulated as an exact solution of the complete Navier-Stokes and energy equations.
RESEARCH REGARDING RESIDUAL SULPHATE SOLUTIONS
CIOBANU DOMNICA, NEDELCU MIRELA, TULBURE MONICA
The technology using the sulphate cellulose from coniferous wood allow for the lignin solubilization, polymer witch exist in chemical composition of wood.The sulphate cellulose purification realized by diffusion process, with industrial water, process which has as a result residual water with alkalilignine pollutant hardly biodegradable. The abatement residual water pollution degree process reported of the Alkalilignine precipitation in acid medium realized with chorine hydride. After lignin separations residual water can be reused in normal biological depuration, excluding primary and second existing steps.
RESEARCH REGARDING THE INCREASING FIABILITY OF BAKERY PRODUCTS WITH REDUCTING EFFECT ON ESSENTIAL PROTEIN BY WHEAT FLOUR
CIOBANU DOMNICA, TULBURE MONICA
By adding the bran and wheat flour germs additive it was establish the qualitative and nutritional growth of diet brad. The economically solution is adding bran in limits of: 10-30% wheat flour. For a normal efficiency of technological results is necessary: yeast 5%, NaCL 2%, germs of wheat flour 1,5%.
A METHOD TO DETERMINE THE DISTRIBUTION OF TEMPERATURE IN CUTTING TOOLS OF GIVEN CONFIGURATION
CIUCESCU DORU, CIUCESCU EDUARD
In order to predict the behavior of tools is is very important to determine the distribution of temperature during cutting. The difficulty of this problem is the impossibility to lay out the thermocouples at the surfaces placed between the cutting tool and the part to be cut. It is known that the rising of the tempering temperature leads to a gradual decrease of the fineness of the phase mixture and consequently to a decrease in hardness. In this paper is presented a method to determine distribution of temperature during cutting based on the hardness obtained after tempering.
ASPECTS OF USING PROTEOLYTIC ENZYMES IN THE BAKERY INDUSTRY
DABIJA ADRIANA *, SION IULIANA *, ANDRONIC CIOCAN DELIA**, MIRON ANCA **
The papers presents theoretical and aspects concerning the usage of proteolityc enzymes in bakery industry. It shows the technological role of proteolityc enzymes in the baking industry, enzymes sources and their actions on some bakery products’ quality. Generally, enzymes, particularly combinations, offer more freedom for optimizing the process and end product. Proteolityc enzymes soften the dough, improve flavour and colour, and help reduce costs.
THEORETICAL STUDY ABOUT THE NEWTON’S BUCKET
FLORESCU DANIELA, FLORESCU IULIAN, PUIU GEORGE
The paper presents a theoretical study about the Newton’s bucket and his applications today. It is know that Isaac Newton conducted more experiments with a bucket containing water, water and rocks, which he described in 1689. His observations and conclusions are presented.
THEORETICAL STUDY ABOUT DEFLECTION CURVE OF THE TELEPHONE CABLE
FLORESCU DANIELA, FLORESCU IULIAN
The present paper presents a theoretical study about the deflection curve, the length and the maximum tension in the uniform cable for the telephones. Over time the forces the cable exerts on telephone pole have caused it to tilt. Proper bracing should be required.
THE STATIC PROBLEM OF THE BUCKET
FLORESCU DANIELA, FLORESCU IULIAN
The paper presents a theoretical study about the free-body diagrams of the bucket and the vertical boom of the back hoe. The bucket and its contents have a weight W. The weight of the members is neglect.
STUDY ABOUT THE DEGRADATION’S RESTRICTION OF THE CYLINDERS
FLORESCU IULIAN, FLORESCU DANIELA
Some machine’s rollers are covered with materials which are ussualy demaged because of their contacts with different chemical substances during the tehnological process. Present paper presents the factors which contribute at the degradation of the rollers and the experimental tests which point the standard of the degradation.
PRINCIPAL ELEMENTS IN RIGHT CHOICE OF KINEMATIC PARAMETERS OF LEADING MECHANISMS FOR NC MACHINE-TOOLS
GHENADI ADRIAN, SILAV CONSTANTIN
Actually the most usually cases are when we know ?s and ?m obtained from the selecting of the engine in the first phase from the condition of driving, the next step being the optimization of the ratio of transmission in concordance to the presented methodology. Many times it is not technical possible the choose of a optimal iT, but it is possible to action in order to obtain a value as near is possible by the optimal value of iT.
THE INFLUENCE OF CRYOGENIC AND ULTRASONIC TREATMENTS ON THE QUANTITY OF RESIDUAL AUSTENITE IN STEELS FOR BEARINGS
GHEORGHIAN MIRELA, CIUCESCU DORU
After quenching and tempering the bearing steel, being a hypoeutectoid one, presents a structure containing martensite, residual austenite and carbides. The rotation precision and the functional role of the bearings impose a good dimensional stability and high mechanical properties. These properties depend on the nature of the natural constituents, their size and distribution and, also, on the degree of structural homogeneity. The technological parameters (temperature and maintaining time) influence the quantity of transformed austenite and the kinetics of this transformation. In this paper is presented the variation of quantity of residual austenite with the cooling temperature under 0oC for the variants of classic treatment: 5 variants of cryogenic treatments and 2 variants of treatment with cooling in ultrasonic field for the 100Cr6 and 100CrMnSi6-4 steels. For these variants of treatments were realized measurements of the quantity of residual austenite by diffraction with X-rays.
THE INFLUENCE OF NON-CONVENTIONAL TREATMENTS ON THE DURABILITY OF BEARINGS
GHEORGHIAN MIRELA, CIUCESCU DORU
The durability represents the main criterion, which imposes itself in the definition of the reliability and of the competition of the bearings. The rotation precision and the functional role of the bearings are realized if it is a good dimensional stability and proper mechanical properties during the running. To fulfill these conditions it is necessary to establish the technological parameters of the processes of primary heat treatment, hot or cold plastic deformation, intermediate heat treatment, mechanical processing, final heat treatment and heat treatment below 0oC or in ultrasonic field. The comparative evaluation of different variants of heat treatment – classic or non-conventional (cryogenic or ultrasonic) which are applied on bearing steels from the point of view of durability have revealed significant increases of the values of real and median du-rability for non-conventional heat treated steels.
ANALYSIS AND DESIGN OF COMBINED INTERLEAVER FOR TURBO CODES
ILIEV TEODOR
In this work are analyze a large number of random interleavers in order to draw conclusions about the characteristics of low - weight codewords. These insights are applied in our research to devise a novel interleaver design algorithm that proves particularly powerful for the case of component encoders with low memory. In this paper we identify the advantages and deficiencies of four design algorithms by analyzing their truncated distance spectra and comparing them each other.
REDUCING ENVIRONMENTAL IMPACTS THROUGH EFFICIENT RECYCLING WASTE MANAGEMENT
KOLIOPOULOS T. C., AXINTE CRINA
This paper presents the major problems which there are in the waste management of our planet. Effective sustainable solutions are proposed in order not only to reduce any associated environmental impacts but also to support sustainable development in our society. Also projections are made of efficient recovery schemes. In the end, useful discussion and conclusions are made for the necessity of using proper recycling technologies.
SUSTAINABLE WASTE MANAGEMENT SCHEMES - A NECESSITY FOR THE ENVIRONMENT
KOLIOPOULOS T. C., KOLIOPOULOU G., AXINTE CRINA
This paper presents the major environmental problems which exist within the waste management in our society. A presentation is made of sustainable waste disposal methods. Moreover, effective useful solutions are proposed in order not only to avoid any associated environmental risks and hazards but also to support a sustainable development of our society. In the end, useful discussion and conclusions are made so as to use protect the public health and the environment.
RESEARCH REGARDING BAKING BAKERY PRODUCTS WITH OATS FLOUR
LEONTE MIHAI, DOMNICA CIOBANU, TULBURE MONICA
Proteins represent 90-95% and include albumins, globulins 30%, gliadin soluble in alcohol 70% and a reduced content of glutenin. Ovenina and the gliadin of oats not form gluten with glutenin and have poor bakery properties.Starch is in top of glucides. Minerals are not distributed uniformly in bean. Oats flour contains vitamins B, PP and enzymes.
RESEARCH REGARDING OF BAKING BAKERY PRODUCTS WITH BARLEY FLOUR
LEONTE MIHAI, TULBURE MONICA, CIOBANU DOMNICA
"To obtain bakery products with functional qualities must use: wheat flour type 800, 94 %; barley flour, 6%; fermentation duration of dough: 33-35 minutes; fermentation temperature of dough: 35ºC; baking duration, 32-35 minute; baking temperature, 200-220 ?C. The transformation of dough in final product is the results of complex process: physical, chemical, biochemical and microbiological."
STUDIES REGARDING THE EFFECT OF TEMPERATURE ON THE QUALITY OF GREEN CHEESE DURING A CONSTANT BOILING PERIOD
LEONTE MIHAI, PIRCU NICOLETA, ARUŞ VASILICA ALISA
As a result of the latest research in the field, one noticed that the most rational way of making good use of whey is the food industry. In this respect, one took interest in the whey, in the by-products resulted from the making of fresh cheese, aiming at the obtaining of green cheese, a highly nutritious aliment. The optimum results regarding the efficiency of green cheese were obtained keeping in mind certain parameters such as: boiling temperature: 80 ?C and boiling time one hour.
PLANNING AN ENGINEERING PROJECT
MACARIE FLORIN, DROB CĂTĂLIN, OLARU IONEL
The planning activity for the management of an engineering project is crucial. Plans are the simulation of a project, comprising the written description of how the Triple Constraint (Time, Performance and Cost) will be satisfied. Therefore, proj¬ect plans are really three plans: one for the performance dimension (the work breakdown structure), one for the schedule dimension (preferably a network diagram but occasionally a milestone listing or bar chart), and one for the cost dimension (a financial estimate). This paper covers plans in general, reiterates the need for plans, describes how these three kinds of plans are made, reviews several planning issues, and discusses a document or series of documents embodying the project`s planning agreements.
MODELING AND OPTIMIZATION OF FRUIT YOGHURT MANUFACTURING PROCESS USING EXPERIMENTS DESIGN PROCEDURES
MIRON DORU NECULAI, NISTOR DENISA, URSU ALINA, ANDRIEŞ IULIANA, MACINCA ANCA GEORGIANA, ILIIN L.
"This paper presents the application of the kn experiment design procedure for simulation and optimization of the yogurt with fruit adding (cherries) manufacturing process. There were performed 27 experiments according to the experiment design procedure choose. The INPUT variables are the fat content of the raw milk (%), the amount of the added fruit (g/100 mL raw material) and the fermentation time (hours); in function of these variables was determined the titrable acidity of the final product."
THE POSSIBILITY OF DETERMINATION POSITION OF A FLOATING SOLID IN A PARTICLES AIR CHANNEL WITH VARIABLE SECTION
MOŞNEGUŢU EMILIAN, NEDEFF VALENTIN, PANAINTE MIRELA, SAVIN CARMEN
the Know of a behavior particle in a air channels with variable section is very importance, for the projection of aerodynamic classification equipment.An important factor it represents the cognition of ultimate position (floating position) which have it a solid particle in the air channel, obtaining thus the level whereat must put the collection box of this. Position of the collection box is can determine on experimental path but and on analytic path (as much for the existing equipment how much fittings and for one finder out in the stage of projection).
CONTRIBUTIONS LOOKING THE EVALUATION OF POLLUTANTS WITH POSSIBILITY OF DEPOLLUTION FOR THE ABOVE-GROUND WATERS
NEDELCU CRISTINA, TULBURE MONICA, CIOBANU DOMNICA
"The saving of watery funds must action in next directions: the intensive use of the water as part of the uses, in the aim of boiled down to at least necessary watery handling watery funds, in the sense creation possibility of satisfied how much the many maul uses in the conditions of variation at the regime of flow funds. For correct the watery consumption, must follow the subsequent: modification and the accommodation procedures technological of utilize the water; replacing the water as the staple and technological factor; recycle interns of the water; systematization nets of casting of the water; reducing the watery loss and enter defended against measure the flows."
RESEARCH CONCERNING LIGNIN UTILIZATION IN MOULDING MIXTURE TECHNOLOGY
NEDELCU CRISTINA, DOMNICA CIOBANU, TULBURE MONICA
The experimental program achieved in this stage, permits the continuation of research in the sight separation of the lignin and prerequisite for skulls this capitalization. According with this situation our target in this case study is to realize products with original technologies in laboratory conditions, lignin representing filling material, with binders from synthetic resins of polycondensation, to confer the products higher reliability.
RESEARCHES CONCERNING THE SOUR CREAM OBTAING USING KINETIC MODIFIERS OF ANIONIC CLAY TYPE
NISTOR DENISA (1), URSU ALINA (1), MIRON DORU NECULAI (1), ARNOLD C. (1), ANDREI MIHAELA (2)
This paper goal is the study of the basic clays influence to some properties of the sour cream obtained by sweet sour. There was determined the titrable acidity and the plasma’s acidity of the sour cream obtained by sweet sour fermentation with selected bacteria cultures and within presence of hydrotalcite clays. Anionic clays develop a basicity that had positive effect on the sour cream thanks to the fact that it can delay the lactic acid influence and accelerate the fermentation. In this paper was performed a kinetic study regarding the influence of the clay amount on sour cream acidity.
PRACTICAL INTEREST OF ROTATING CONDENSATION
OLARU IONEL, CĂLIMAN RADU
The problem of rotating condensation is formulated as an exact solution of the complete Navier-Stokes and energy equations. Numerical solutions are obtained for Prandtl numbers between 0.003 and 100 and for cp?T/hfg in the range 0.0001 to 1.0.
MODALITIES TO DETERMINE THE ENERGY CONSUMPTION FOR THE GRINDING OF VEGETABLES PRODUCT WITH VARIABLE TEXTURE
PANAINTE MIRELA (1), DAŠIÆ PREDRAG (2), NEDEFF VALENTIN (1), MOŞNEGUŢU EMILIAN (1), SAVIN CARMEN (1)
grinding process of vegetable products is complicated. This is explain through the fact that vegetables product are inhomogeneous and with variable properties in time and space. The working methods chosen take into account that the grinding operation must lead to a product qualitative superior as well as low energy consumption.
THE PROCURANCE AND THE USE OF CLAYS CHEMICALLY MODIFIED IN DECONTAMINATION PROCESSES
PLATON NICOLETA (1), SIMINICEANU ILIE (2), NISTOR DENISA (1), MIRON DORU NECULAI (1)
Pillared clays have drawn a great deal of attention, due to their catalytic and textural properties in different reactions. In this work we present a theoretical study regarding the process of clay pillaring in time inside the laboratory. One should consider extending it to the industrial level. The importance that pillared clays have on the protection of the environment is very high.
CONTROL OF INDUSTRIAL EQUIPMENTS USING EMBEDDED APPLICATIONS
POPESCU CORNEL, CULEA GEORGE, DRĂGAN ALEXANDRU
"This paper presents a flexible implementation for an embedded application capable to acquisition data and to control an industrial process. The paper is structured into several parts. First, there is presented the goal of the work and how this purpose will be achieved taking into account to actual trends. The second part describes design specifications and technologies used to this application. Thus, it makes a functional presentation of the implemented application. Next part shows the implementation of the application. The paper concludes with some significant results and some considerations about this embedded application; also, is presented some future research."
MODELING AND OPTIMIZATION OF THE SEWAGE FILTRATION ON POROSIL USING EXPERIMENTS DESIGN PROCEDURES. I. A MICROBIOLOGIC STUDY
RĂDUCANU D. (1), AILIESEI O. (2), URSU ALINA (1), NISTOR DENISA (1), MIRON DORU NECULAI (1), CIORCILĂ S. (1), POPA F. (3)
This paper presents a study regarding the purification degree of waste water using porosil like filler material. The experiments were realized using a factorial 33 Experiment design, intending, in the same time, to realize the mathematical simulation and optimization of germs retention by filtered surfaces. The mesophilic germs content of sewage samples are influenced by filtered media characteristics and by physico/chemical properties of sewage. The results obtained are donned in tabular and graphical forms.
STUDIES AND RESEARCHES ABOUT THE MIXING PROCESS OPTIMIZATION AND ABOUT MIXING DEVICES IN CASE OF THE NON-NEWTONIAN MIXTURES
SAVIN CARMEN, NEDEFF VALENTIN, ZICHIL VALENTIN, PANAINTE MIRELA, MOŞNEGUŢU EMILIAN
The study has as objective the optimization of the mixing process of products with variable viscosity by optimum chooses of function parameters.To achieve the objectives of this study it was made researches about the viscosity of non-Newtonian mixtures by S-L, propriety which characterise the homogenisation degree and power consumption.To realise the experimental researches, it was used a laboratory stand which allows the study of mixing process of non-Newtonian mixtures with variable viscosity.During the study it was made the simulation of mixing process hedged by ANSYS soft, based on the method of finite element.
AN ANALYTIC VIEW ON PRECISION CASTING
SIMIONESCU GHEORGHE, CIUCESCU DORU
The casting of liquid metal into a mould is a convenient way of making many types of components. Many times the casting process is the only suitable method to fulfill both practical and economical exactingnesses. Among main casting methods there are some of them which ensure close dimensional tolerances and with a good surface finish named generically high precision casting. In this paper are presented some broad considerations on the perspectives of the precision casting.
AN APPROACH TO DETERMINE THE NECESSARY EQUIPMENT IN A FOUNDRY WORKSHOP
SIMIONESCU GHEORGHE, CIUCESCU DORU
The processes to obtain the casts imply many complex operations starting from the sand storehouse to the fettling shop. The mechanization and the automation of the technological flux are realized by using advanced equipment. A very important problem is to establish the type and the number of technological installations. In this paper are presented some ways to calculate the number of technological installation in the melting and alloying shop.
THE STATIC AND DYNAMIC ANALYSIS OF THE FEED KINEMATICAL LINKAGES OF THE MACHINE TOOLS CNC
STAN GHEORGHE
The feed kinematical linkages of the numerical control machine tools have a direct and decisive influence on the machining accuracy. Their research in closed loop (for the speed and position circuits) is definitely needed, as the transient duty of the linkage participates directly to the path error of the work piece being machined. This paper presentsa theoretical research method of the kinematical linkage as a whole, based on patterns, offering important data on the system performance.
THE BACKLASH COMPENSATION OF A FEED KINEMATICAL LINKAGES OF THE MACHINE TOOLS CNC
STAN GHEORGHE
The high accuracy of the numerical control machine tools especially of the machine tools performing interpolations requires new conditions that have to be fulfilled by the feed kinematical linkages. The aim of this paper is to systemize the compensation systems being used by the machine tool builders, showing the advantages and disadvantages of each one. The relation of the kinematical linkage to the numerical control equipment is also considered, as well as the electronic compensation possibilities of the latter.
ARTIFICIAL SOLUTIONS FOR DOUBLING OR TRIPLING THE WEIGHT OF A STEEL PIECE, BY BALLASTING
TĂNASE CLAUDIA, ŞTEFĂNESCU, NECULĂIASA VASILE
The significant increase in weight of a mobile steel piece, with an essential function in generating the percussions with high impact energy, cannot be approached without radically changing the inner structure of the piece. Keeping the geometric shape of the piece, combined structures, bi or tri-polar , can be created, able of doubling or even tripling its weight, using the technique of ballasting with known super heavy materials.At this moment, in car-building, they stress upon the use of super heavy materials, able of major energetic performances in the main work body, as an alternative to similar pieces, made only of steel.
THE MICROSTRUCTURE AND MECHANICAL CHARACTERISTICS OF ORTHOTROPIC MATERIALS
UNGUREANU VIOREL
Usually, in order to determine the mechanical characteristic of metallic material is used the tensile test. But, for orthotropic sheet metal testing the tensile test is not representative and is proposed the utilization of planar sharing, planar stretching and compression tests. Those testing methods are easy to implement on conventional testing machines and the obtained results may be used in the sheet metal forming analysis and in the understanding of mechanical behavior of orthotropic materials.
MATHEMATICAL MODELING AND OPTIMIZATION OF CREAM CHEESE MANUFACTURING USING FACTORIAL DESIGN PROCEDURES
URSU ALINA (1), NISTOR DENISA (1), MIRON DORU NECULAI (1), GRIGORAŞ ADINA (1), MĂCINCĂ ANCA GEORGIANA (1), ANDREI MIHAELA (2)
This paper presents a study regarding the optimization and mathematical simulation of the cream-cheese with adding’s (dried parsley) manufacturing process using a factorial 33 experiment designs. The 27 experiment were performed in different conditions, the varying operating parameters for the 33 factorial experiment designs were: the melting temperature (x1), the melting time (x2) and the quantity of dried parsley added (x3). This study provide the information’s regarding the effect of melting temperature, melting time and the quantity of adding’s when the melting salts amounts were fixed.