Volume 12 / 2014 Issue 2

1. EDITOR'S NOTE

2. CONTENT OF ACADEMIC JOURNAL OF MANUFACTURING ENGINEERING

3. ABSTRACT

  

1. EDITOR'S NOTE

INTERNATIONAL CONFERENCE IManE 2014

The conference IManE 2014 means firstly the result of collaboration between the departments of machine manufacturing technologies from the Technical University of Moldova of Chişinău (Republic of Moldova) and from “Gheorghe Asachi” Technical University of Iaşi (Romania). Between 2009 and 2012, the conference had the title „Modern Technologies, Quality and Innovation”; for some years, the Institute of Technical Science of the Serbian Academy of Sciences and Arts participated as co-organizer to this scientific event. From 2013, in accordance with the evolution of machine manufacturing technologies, the name of the conference was changed in “Innovative Manufacturing Engineering” (IManE).

Nowadays, the technology is a concept with multiple significances in various economical and even non economical fields. Thus, one can meet technologies applied in education, medicine, culture etc. For us, the technologies applied in machine manufacturing are important; due to this importance of machine manufacturing technologies, there is an increased interest and preoccupations for introducing/applying new or improved technologies, in order to enhance the product competitiveness, to diminish the production costs, to increase the manufacturing productivity etc.

The IManE conference developed in May 2014 received papers which were presented within 9 sections, concerning fields such are Advanced Machining and Surface Engineering, Assembling Technologies, Forming Technologies, Non-Conventional Technologies in Manufacture and Industry, Welding Technologies, Advanced Materials and Construction Technologies, Flexible Manufacturing, Automation and Robotics in Technological Processes, CAD/CAM/CAE/CAx Technologies, Manufacturing Optimization, Mechanical and Manufacturing Equipment, Devices and Instrumentation, Design and Analysis, Innovation, Creativity, Learning and Education in Engineering, Industrial and Product Management, Quality and Evaluation.

The organizing of the conference benefited of the help offered by many of our colleagues working in Republic of Moldova, Romania and other countries; for this reason, we express our gratefulness to all specialists involved in various phases of preparing the scientific event. The papers presented within the conference will be published in the journal Applied Mechanics and Materials. In accordance with the publisher, extended versions of some selected papers are published in this issue of the Academic Journal of Manufacturing Engineering.

We hope that the conference and the research results communicated and published within the conference IManE 2014 were a good occasion to develop new collaborations among the participants to this scientific event.

Associate Professor Sergiu Mazuru
Technical University of Moldova, Chişinău, Republic of Moldova
 
Professor Oana Dodun
“Gheorghe Asachi” Technical University of Iaşi, Romania
 
Professor Laurenţiu Slătineanu
 “Gheorghe Asachi” Technical University of Iaşi, Romania

 

2. CONTENT OF ACADEMIC JOURNAL OF MANUFACTURING ENGINEERING VOL.12, ISSUE 2/2014

1. Editor’s Note: INTERNATIONAL CONFERENCE IManE 2014 ......................
2. RESEARCHES TO IMPROVING TOOL LIFE OF THE CUTTING INSERTS COATED WITH TITANIUM THIN LAYERS -- Ana BĂDĂNAC, Octavian LUPESCU, Vasile MANOLE, Ovidiu Toader RUSU...................................................................
3. GRAPHICAL METHOD FOR PROFILING THE TOOLS WHICH GENERATE INTERNAL SURFACES BY ROLLING -- Silviu BERBINSCHI, Virgil Gabriel TEODOR, Gabriel R. FRUMUŞANU, Nicolae OANCEA........................................................
4. MACHINABILITY INVESTIGATION OF AISI W1 TOOL STEEL BY HARD FACE MILLING -- Irina BEŞLIU ...................................................................................... 
5. BEARING SCUFFING DETECTION AND CONDITION MONITORING USING VIRTUAL INSTRUMENTATION -- Carmen BUJOREANU, Florin BREABĂN .......
6. NUMERICAL SIMULATION OF PLASTIC DEFORMATION PROCESSES FROM CAST IRON PARTS -- Tudor CHERECHES, Paul LIXANDRU, Sergiu MAZURU, Pavel COSOVSCHI, Daniel DRAGNEA .............................................
7. SOME ASPECTS REGARDING THE INFLUENCE OF TEMPERATURE IN A WIM HYDRAULIC SYSTEM -- Irina MARDARE, Irina TIŢA..........................................
8. CONVERGENT USE OF ADVANCED CAD/CAE/CAM CAPABILITIES FOR SUSTAINABLE INTEGRATED ENGINEERING -- Vasile MERTICARU, Gheorghe NAGIT, Bogdan PRALEA, Robert OANA ................................................................. 
9.PREPARATION STEPS OF A CONNECTING ROD'S 3D GEOMETRY TO BE MANUFACTURED ON A NC CENTER -- Marius Andrei MIHALACHE, Gheorghe NAGȊŢ, Marius Ionuţ RȊPANU, Mihai BOCA ...........................................................
10. WORK SPEED AT RAM ELECTRICAL DISCHARGE MACHINING OF EXTERNAL CYLINDIRCAL SURFACES -- Ciprian MIRCESCU, Laurenţiu SLĂTINEANU, Margareta COTEAŢĂ, Irina BEŞLIU, Oana DODUN, Miroslav RADOVANOVIC ...................................................................................................
11. SOLUTIONS FOR THE INTERNAL KEYWAYS POSITION DEVIATION MEASUREMENT -- Adriana MUNTEANU, Florentin CIOATA ...........................
12. CUTTING TOOLS FOR GENERATING OF ROTORS COMPRESSORS -- Camelia POPA, Virgil Gabriel TEODOR, Nicuşor BAROIU, Silviu BERBINSCHI ..................
13.THE TIGHTENING ACCURACY OF WORKPIECES IN THE MULTIPLE CLAMPING DEVICES -- Neculai-Eugen SEGHEDIN Dragoş-Florin CHITARIU ... 
14. SELECTING OF MEASURING INSTRUMENTS -- Pavlina TOTEVA, Dimka VASILEVA, Nadezhda MIHAYLOVA ..................................................................... 
15.NEW STANDARDS IN THE FIELD OF GEOMETRICAL PRODUCT SPECIFICATIONS -- Pavlina TOTEVA, Dimka VASILEVA, Nadezhda MIHAYLOVA
16. SURFACE INVESTIGATION OF CORRODED NITI SHAPE MEMORY ALLOY -- Adela Dragoş URSANU, Sergiu STANCIU, Nicanor CIMPOESCU, Ramona CIMPOEŞU, Mihaela RĂŢOI, Armand ENACHE ..................................................................... 
17. FUNCTIONAL DIAGRAM FOR COMPARATIVE ANALYSIS OF ELECTROMAGNETIC BALL VALVES -- Dănuţ ZAHARIEA .............................

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3. ABSTRACT

RESEARCHES TO IMPROVING TOOL LIFE OF THE CUTTING INSERTS COATED WITH TITANIUM THIN LAYERS PDF

Ana BĂDĂNAC-1, Octavian LUPESCU-1, Vasile MANOLE-1 and Ovidiu Toader RUSU-2

1 - Universitatea Tehnică ”Gheorghe Asachi” din Iaşi, Facultatea de Construcţii de Maşini şi Management Industrial, Departamentul TCM, Blvd. D. Mageron 59A, 700050, Iaşi, România

2 - Universitatea “Stefan cel Mare” din Suceava, Facultatea de Inginerie Mecanică, Departamentul Mecanică Aplicată şi Tehnologii, str. Universităţii 8-9 Corp B, 720485, Suceava, România

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ABSTRACT: It is known that the cutting tools wear more or less accentuated in cutting processes may occur, due to the unevenness of the cutting depth, to the machining parameters variation, as well as due to the existence or nonexistence of the coolant oiling. The cutting tools lives being influenced by all these factors in dominant and negative mode, one can impose actions and decisions to reduce the wear processes of the tools or/and of the cutting inserts. For increasing the durability of the cutting inserts, there are known numerous researches concerning their coating with material (ions) by vacuum deposition, using methods as thermal evaporation, ionic plating, pulverization or chemical vapor deposition. The authors propose to improve the cutting tools lives using the deposition method by ionic plating in vacuum (PVD) with thin titanium layers, following the cutting tools behavior in operation treated in this way.

KEY WORDS: carbide cutting inserts, tool life, titanium thin layers, ionic plating, machining test.

GRAPHICAL METHOD FOR PROFILING THE TOOLS WHICH GENERATE INTERNAL SURFACES BY ROLLING PDF

Silviu BERBINSCHI-1, Virgil Gabriel TEODOR-1, Gabriel R. FRUMUŞANU-1 and Nicolae OANCEA-1

1 - Universitatea “Dunărea de Jos”, Domnească 111, 800201 Galaţi, România

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ABSTRACT: In this paper, we present a graphical method, developed in CATIA environment, based on the method of substituting circles family and dedicated to profile pinion cutters for generating interior surfaces. Hereby, the family of substituting circles associated to the worked piece (the profile to be generated) is determined at the same time to the curve transposed, in the rolling motion, to the tool centrode. After finding the position of the contact points between the generated profile and the family circles, we can determine, in the transposed family, the locus of the points from the reciprocal enwrapping profile – the pinion cutter profile. The paper also includes two method applications, for generating a hole with square transversal section, and a pump stator with trapezoidal profile. Comparisons between the profiling results when using the graphical method, versus an analytical method have also been realized. The results are proving the coincidence between the two profiles determined as above, on one hand, and both rapidity and precision of the graphical method, on the other hand.

KEY WORDS: graphical method, CATIA, profiled holes, pinion cutter.

MACHINABILITY INVESTIGATION OF AISI W1 TOOL STEEL BY HARD FACE MILLING PDF

Irina BEȘLIU-1

1 - Universitatea Ştefan cel Mare din Suceava, Departamentul de Mecanică și Tehnologii, Universității 13, Corp B, Suceava, România

E-mail: irina.besliu&yahoo.com

ABSTRACT: Hard milling is considered to be an expanding field. This paper studies some machinability aspect and process viability of hard face milling AISI W1 tool steel with different hardened states. The process performances are determined in terms of surface quality, cutting force and chip formation mechanism. The outcomes suggest that these machining processes can compete with other finishing techniques.

KEY WORDS: hard machining, machinability, hardened tool steel, cutting force, surface integrity.

BEARING SCUFFING DETECTION AND CONDITION MONITORING USING VIRTUAL INSTRUMENTATION PDF

Carmen BUJOREANU-1 and Florin BREABĂN-2

1 - Universitatea Tehnică “Gheorghe Asachi” din Iaşi, Departamentul de Inginerie Mecanică, Mecatronică şi Robotică, Dimitrie Mangeron 43, 700050 Iaşi, România

2 - Université d'Artois / LGCgE. IUTB, S2T 1230 Rue de l'Université 62408, Béthune, France

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ABSTRACT: Diagnostic methods including bearing problems represent one of the most important challenges. The scuffing phenomenon initiation of the bearing elements produces an important increase in the vibration level and can be emphasized by the analysis of the bearing friction forces which are the most sensitive indicator of the bearing failure. Commonly used technique for damage detection is the vibration signature analysis that must be carefully utilized in conjunction with the friction torque monitoring through the strain gauges measurements. In order to detect the scuffing onset, the paper presents an experimental setup for the scuffing tests performed on a 7206 ball bearing. A virtual instrument monitoring the friction force respectively the braking torque was created. An accelerometer captures the signal from the bearing outer ring then it is processed using PCI-4451 National Instruments data acquisition board and LabVIEW soft.

KEY WORDS: scuffing, ball bearing, test device, condition monitoring, virtual instrument.

NUMERICAL SIMULATION OF PLASTIC DEFORMATION PROCESSES FROM CAST IRON PARTS PDF

Tudor CHERECHES-1, Paul LIXANDRU-1, Sergiu MAZURU-2, Pavel COSOVSCHI-3 and Daniel DRAGNEA-1

1- SC UPS PILOT ARM SRL, Dragomiresti, 137210, România

2 - UTM FIMCM, Str. Studentilor, 9, Blocul de Studii nr. 6, MD-2045, Chisinau, Moldova Republic

3 - FABRICA DE STICLA, Chisinau, str.Transnistria nr. 20, Moldova Republic

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ABSTRACT: One of the various proceedings for material cold-work hardening is the smooth finishing by superficial plastic deformation with hard tools from metallic carbide or diamond. According to this procedure, the active workpiece faces are pressed with a tool, generally ball-shaped, which has a spatial compound movement. The contact between tool and workpiece, also in motion, is force/displacement controlled. This paper describes a numerical simulation for study of the such-like procedure, used for cast iron parts. An accurate physical model for technological process was stated. The attention was focused on the material elastic-plastic properties and on constitutive equations. The finite element discretization with more fine mesh in the superficial layers of the workpiece active faces was achieved. The LS-DYNA explicit dynamic code was used for solving and analyses. The numerical simulation was applied on workpieces of revolution, manufactured by contour turning.

KEY WORDS: numerical simulation, LS-DYNA, physical model, mathematical model, numerical solution.

SOME ASPECTS REGARDING THE INFLUENCE OF TEMPERATURE IN A WIM HYDRAULIC SYSTEM PDF

Irina MARDARE-1 and Irina TIŢA-1

1 - “Gheorghe Asachi” Technical University of Iaşi, Blvd. D. Mangeron, 59A, 700050, Iasi, Romania. Department of Fluid Mechanics, Fluid Machinery and Fluid Power Systems

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ABSTRACT: Weighing in motion systems (WIM), regardless the type of sensor that the system utilizes, works in difficult conditions: dust, slag, layer of ice or snow, high humidity, varying temperatures during a day, or a year. All these conditions have impact on the accuracy of measurement and require considering the correction factors. In this paper it is presented the analysis of the temperature influence on a weighing in motion sensor. It is examined a type of WIM sensor actually rarely used, namely a hydraulic sensor, in order to see performances of such a solution. On the basis of a proposed structure for experimental model, it is presented the corresponding SimHydraulics block diagram, considering some aspects regarding the decision for choosing one or another solution. Using this block diagram and considering different values for the temperature, some results and consequently some conclusions were obtained.

KEY WORDS: weigh-in-motion hydraulic system, temperature influence, SimHydraulics block diagram, simulation.

CONVERGENT USE OF ADVANCED CAD/CAE/CAM CAPABILITIES FOR SUSTAINABLE INTEGRATED ENGINEERING PDF

Vasile MERTICARU-1, Gheorghe NAGIT-1, Bogdan PRALEA-1 and Robert OANA-1

1 - ”Gheorghe Asachi” Technical University of Iasi, Prof. D. Mangeron Str., no. 39, 700050 – Iasi, Romania

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ABSTRACT: The presented research approach is oriented toward the general problem of sustainable product development and more specifically, the idea of convergent use of advanced CAD/CAE/CAM capabilities is targeted as instrument to provide sustainable integrated engineering. A complex conceptual model for the convergent use of integrated engineering tools as strategy for sustainable product development is proposed and discussed in the paper. As case study, the paper subjects to discussion the problem of identifying, selecting, combining and aligning the best options to the needs, for the CAD/CAE/CAM/PDM activities within the process of product development for complex injection moulds designated to automotive industry. Finally, some adequate conclusions of the research approach are presented, oriented mainly in the direction of how a product developer should manage its integrated engineering activities.

KEY WORDS: sustainable product development, integrated engineering, CAD/CAE/CAM, technological convergence, injection mould.

PREPARATION STEPS OF A CONNECTING ROD'S 3D GEOMETRY TO BE MANUFACTURED ON A NC CENTER PDF

Marius Andrei MIHALACHE-1, Gheorghe NAGȊŢ-1, Marius Ionuţ RȊPANU-1 and Mihai BOCA-1

1 - "Gheorghe Asachi" Technical University of Iasi, Department of Machine Manufacturing Technology, Blvd. D. Mangeron, No.59A, Iasi-700050, Romania

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ABSTRACT: This case study presents a sequence of operations performed in a 3D environment, in order to obtain a full physical replica of a previously optimized 3D geometry of a connecting rod by means of NC driven manufacturing process. The method highlights some of the technical impediments that can be found along the process, as it is custom fitted to a certain part model. It produced valid NC codes written in the G code. The post-processor involves the NC center that was used for the actual manufacturing including its tools setup. The connecting rod's 3D geometry was divided in two sections and considered individually as its head and body. Only important operations are presented in the study and the overall results that they produced. It also presents some operations regarding generation and export techniques that were used to obtain G code files fed afterwards to the NC center. The procedure aims to be a valid alternative to the classical forging process of connecting rods.

KEY WORDS: 3D setup, connecting rod, NC manufacturing.

WORK SPEED AT RAM ELECTRICAL DISCHARGE MACHINING OF EXTERNAL CYLINDRICAL SURFACES PDF

Ciprian MIRCESCU-1, Laurenţiu SLĂTINEANU-1, Margareta COTEAŢĂ-1, Irina BEŞLIU-2, Oana DODUN-1, Miroslav RADOVANOVIC-3

1 - “Gheorghe Asachi” Technical University of Iaşi, Department of Machine Manufacturing Technology, Blvd. D. Mangeron, 39 A, 700050 Iaşi, Romania

2 - University "Ştefan cel Mare" of Suceava, Department of Mechanics and Technologies, Universităţii Street 13, 720229 Suceava, Romania

3 - University of Niš, Department of Production Engineering, Aleksandra Medvedeva 14, 18000 Niš, Serbia

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ABSTRACT: The electrical discharge machining can be sometimes applied in order to obtain external cylindrical surfaces. Such a problem appeared as a consequence of the necessity to extract a cylindrical test sample from a part made of difficult to cut material. The analysis proved the possibility to use a tubular tool electrode and a classical machining scheme valid in the case of ram electrical discharge machining. The method of full factorial experiment was applied in order to design the experimental research. As input parameters, one considered the pulse on time, off time and discharge peak intensity. An investigation concerning the influence exerted by these input parameters on work speed was developed. A power type empirical mathematical model was determined by mathematical processing of the experimental results. The power type function and graphical representations proved the significant influence exerted by discharge peak current.

KEY WORDS: ram electrical discharge machining, tubular tool electrode, work speed, influence factors, empirical model.

SOLUTIONS FOR THE INTERNAL KEYWAYS POSITION DEVIATION MEASUREMENT PDF

Adriana MUNTEANU-1 and Florentin CIOATA-1

1 - ”Gheorghe Asachi” Technical University of Iaşi, Department of Machine Tools, Blvd. D. Mangeron, 59 A, 700050 Iaşi, Romania

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ABSTRACT: The measurement of symmetry and nominal position deviation from theoretical point of view is not a problem, the main issues appears when these theoretical aspects aren’t applicable in industrial practice. The problem addressed in this paper is to identify the possibility to develop a method for the intermediary control like a necessity to industrial practice but for a small series production. A theoretical analysis was developed in order to identify the measuring possibility of symmetry and nominal position deviation for a specific keyway. Using chart ideas and making a case study, we thought to find a practical solution of the intermediary control for specific keyways gears, in small series production case. The research tries to highlight some common and distinct aspects specific for those measuring methods and to solve the issue of intermediary control for a small series production in case of gears internal keyways.

KEY WORDS: internal keyway, measurement, nominal position deviation, symmetry, control device.

CUTTING TOOLS FOR GENERATING OF ROTORS COMPRESSORS PDF

Camelia POPA-1, Virgil Gabriel TEODOR-2, Nicuşor BAROIU-2 and Silviu BERBINSCHI-1

1 - “Dunărea de Jos” University of Galaţi, Mechanical Engineering Department, Domnească 111, 800002

2 - “Dunărea de Jos” University of Galaţi, Depart. of Manufacturing Engineering, Domnească 111, 800002

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ABSTRACT: The compressor rotors usually are helical surfaces with constant pitch and are composed of crossing profiles. Frequently, for repair operations, the reconstruction necessity occurs for one or both of the worms, drive and driven, from the helical compressors gear. The theoretical helical surface of the worm is being substituted by an assembly of helical lines which together with crossing profiles forms points cloud resulted from measuring leads to a polyhedral expression of the flank rotor. Numerically, this surface type is expressed by a coordinate array which shows its discrete image. The profiling of cutting tool bounded by a revolution surface reciprocally enveloping with the substitutive surface of the helical one represents a special problem. In this paper is proposed an algorithm for polyhedral expression of the helical surface previously determined by reverse engineering methods and an algorithm for the determination of the specific enveloping condition at contact with a discrete surface. It is presented an example for a compressor rotor measured on a 3D measuring machine, the algorithm for the transformation of the gathered points cloud in a surface with polyhedral expression. Given these conditions there were determined the enveloping condition and the axial section of the side mill.

KEY WORDS: helical compressor, reverse engineering, side mill profiling, polyhedrons method.

THE TIGHTENING ACCURACY OF WORKPIECES IN THE MULTIPLE CLAMPING DEVICES PDF

NECULAI-EUGEN SEGHEDIN-1 and DRAGOŞ-FLORIN CHITARIU-1

1 - Technical University “Gheorghe Asachi”, Street Prof. Dr. Doc. D. Mangeron 67, Iaşi, Romania

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ABSTRACT: Fixtures are used for orientation-positioning-tightening of workpieces during machining on machine tools. Multiple clamping fixtures are intended to clamp several workpieces for simultaneous or successive machining. Multiple clamping is characterized by a series of economical advantages, due to the reduction of total machining time. These advantages are more important once the number of workpieces is higher or if the machining is made with compound tools. Due to the complexity, overall size and the high number of components, the multiple clamping fixtures have diminished accuracy than simple fixture due to elastic and contact deformations of fixtures housing, of supports etc. Also, multiple clamping fixtures present diminished rigidity and dynamic stability. From the analysis of the specialized literature results that there are a few paper on the subject of multiple clamping. In the paper there are presented the causes that can lead to the diminishing of the accuracy of multiple fixture. The modalities for the determination of fixtures precision are presented, also, for the parallel and serial multiple clamping fixtures.

KEY WORDS: fixtures, multiple clamping, clamping mechanisms, accuracy, machine tools.

SELECTING OF MEASURING INSTRUMENTS PDF

Pavlina TOTEVA-1, Dimka VASILEVA-1 and Nadezhda MIHAYLOVA-1

1 - Technical University of Varna, Studentska 1 Str., 9000 Varna, Bulgaria

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ABSTRACT: One of the tasks at planning of quality inspection is selection of measuring instruments. The measuring instruments are the most important part of the measuring process, so that their selection has to be done carefully. The selection of measuring instruments is a complex task, which depends on the size, the character and the value of measured magnitude. The purpose of this paper is to analyze the existing methods for selection of measuring equipment. In the paper, there are presented the advantages and disadvantages of existing methods and recommendation for their implementation, according to the metrological tasks given. There are results obtained, using the Measurement System Analysis (MSA), for selection of the correct measuring instrument and method; assessment the capabilities of measuring instruments.

KEY WORDS: measuring instruments, accuracy, capabilities.

NEW STANDARDS IN THE FIELD OF GEOMETRICAL PRODUCT SPECIFICATIONS PDF

Pavlina TOTEVA-1, Dimka VASILEVA-1 and Nadezhda MIHAYLOVA-1

1 - Technical University of Varna, Studentska 1 Str., 9000 Varna, Bulgaria

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ABSTRACT: The essential tool for improving product quality and reducing manufacturing costs is the implementation of standards relating to a product. The main group of ISO standards are the standards related to Geometrical Product Specifications (GPS), where the requirements for detail geometrical characteristics that determine the execution of the functional purpose of the products are given. The purpose of this paper is to present the new standards of geometrical dimensioning and tolerancing of linear sizes, accuracy of form, as well as orientation and position of surfaces and axes. There are indicated problems associated with the implementation of the standards under consideration in Bulgaria and the ways to rectify them.

KEY WORDS: geometrical product specification (GPS), ISO, standards, geometrical characteristics, tolerancing.

SURFACE INVESTIGATION OF CORRODED NiTi SHAPE MEMORY ALLOY PDF

Adela Dragoş URSANU-1, Sergiu STANCIU-1, Nicanor CIMPOESU-1, Ramona CIMPOEŞU-1, Mihaela RĂŢOI-1, Armand ENACHE-2

1 - Technical University “Gheorghe Asachi” from Iasi, Materials Science and Engineering Faculty, Prof. dr. doc. D. Mangeron Street, no. 41, Iaşi, 700050, România

2 - University of Medicine and Pharmacy “Gr. T. Popa”, Faculty of Medicine, University str. no 16, 700115, Iaşi, Romania

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ABSTRACT: A shape memory alloy with medical applications was analyzed by corrosion point of view in Fusayama artificial solution after few thousand experimental cycles. Scanning electrons microscope, EDAX and potentiostat equipments were used to characterize the material surface and its behavior during and after an electric polarization. Pitting corrosion type was observed on the surface with accentuated aspects based on the fatigue process. Dimensional characterization of the pitting holes was realized using 2D and 3D imaging software possibilities and chemical modifications were analyzed in and near the corrosion marks.

KEY WORDS: NiTi shape memory alloy, corrosion resistance, cyclic potentiometry, scanning electron microscopy.

FUNCTIONAL DIAGRAM FOR COMPARATIVE ANALYSIS OF ELECTROMAGNETIC BALL VALVES PDF

Dănuţ ZAHARIEA-1

1 - Universitatea Tehnică “Gheorghe Asachi” din Iaşi, Facultatea de Construcţii de Maşini şi Management Industrial, Departamentul de Mecanica Fluidelor, Maşini şi Acţionări Hidraulice şi Pneumatice, Dimitrie Mangeron 59A, 700050, Iaşi, România

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ABSTRACT: The main objective of this paper is to perform a comparative numerical analysis of an electromagnetic normally-closed direct-acting ball valve with two types of seats: cylindrical and conical. A functional diagram is developed using the MATLAB/Simscape/SimHydraulics programming language. The principal elements of the functional diagram are: the fixed-displacement hydraulic pump, the ball valve which is driven by an electromagnetic actuator, the pressure-relief valve, pressure and volumetric flow rate measuring devices and the hydraulic pipes. Two sets of analyses are performed; the first one will study the influence of the effects that are associated with the hydraulic pipes on the ball valve with conical seat. The second set of analyses will evaluate the influence of the seat (cylindrical and conical) on the principal functional characteristics of the ball valve: the valve flow factor, the volumetric flow rate through the ball valve and through the pressure relief valve and the valve pressure drop.

KEY WORDS: electromagnetic ball valve, functional diagram, MATLAB, Simscape, SimHydraulics.