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Vijčano-ekscentrične pumpe imaju široko područje primjene u industriji zbog svoje jednostavne konstrukcije i zbog mogućnosti transportiranja medija različite viskoznosti. Isto tako, zbog modularne gradnje pojednostavljeno je održavanje takvih pumpi. Jedini ograničavajući faktor primjene ovakvih pumpi predstavlja temperatura transportiranog medija. U ovom završnom radu opisana je osnovna podjela pumpi, navedena su područja njihove primjene u industriji te su dane njihove karakteristike i neke od učestalih pojava kod rada pumpi. Osim toga, objašnjen je osnovni princip rada vijčano-ekscentričnih pumpi te je dana podjela vijčanih pumpi. Detaljnije je opisana konstrukcija jednovijčane ekscentrične pumpe, gdje je posebna pozornost pridana kardanskom vratilu i rotoru vijčano-ekscentrične pumpe. U praktičnom dijelu ovog završnog rada prikazan je tehnološki postupak izrade rotora vijčano-ekscentrične pumpe na klasičnim alatnim strojevima. U tom dijelu su navedeni svi potrebni postupci obrade te pripadajući alati i potrebni alatni strojevi. Progressive cavity pumps have a wide range of application in industry because of its simple construction and ability to transport media with different kind of viscosity. Also, because of their modular construction, the maintenance of these kind of pumps is simplified. The only limiting factor of application for this kind of pumps is represented by the temperature of transported media. In this bachelor thesis there is described the basic division of pumps, there is specified the application areas of pumps in industry and there are also given some of their characteristic and also some of frequently processes that are likely in operation of these pumps. Furthermore, it is explained the basic work principle of progressive cavity pumps and there is also given division of screw pumps. More detailed is described the construction of one-screw progressive cavity pump, where a special attention is given to cardan shaft and rotor of progressive cavity pump. In the practical part of this bachelor thesis is shown the technological process of production a rotor for the progressive cavity pump made on classical tool machines. In that part there are listed all necessary processing procedures and belonging tools and tools machines.

U ovom radu je teorijski obrađena tema primjene CNC tehnologije u projektiranju kalupa za izradu središnjeg dijela boce. Potrebno je projektirati kalup tako da se tim kalupom mogu izraditi boce volumena jedne litre. Sastavni dijelovi kalupa, poput dna kalupa, grla kalupa te ostalih dijelova su preuzeti već od postojećih kalupa za boce. Sam središnji dio kalupa je projektiran tako da na boci bude jasno vidljiv znak Fakulteta strojarstva i brodogradnje, natpis Sveučilište u Zagrebu, te skraćenica KAS, kao skraćenica za Katedru za alatne strojeve. Početna točka bila je izrada modela boce, zatim kalupa te na kraju generiranja NC koda. Dizajniranje i generiranje NC koda je provedeno u CAD/CAM programu CATIA. In this paper is presented application of the CNC technology in making the central part of mould for the glass bottle. The mould was designed for the making of the 1 liter glass bottles. Other components of the mould, like bottom and neck were took from already existing moulds for the glass bottles. Mould was designed so that on the glass bottle are visible sign of the Faculty of the Mechanical Engineering and Naval Arhitecture, inscription "Sveučilište u Zagreb" and abbreviation "KAS" which represents Katedra za Alatne strojeve. Starting point of this work was creating model of glass bottle, following with mould model and at the end generating NC code for the machine. Designing of the model and generating NC code was conducted in CAD/CAM software CATIA.

U ovom radu razrađena je tehnologija izrade dijelova transportnog modula koji služi za transport proizvoda u prehrambenoj industriji. U radu su navedeni uvjeti, propisani od strane Europske grupe higijenskog inženjerstva i dizajna, koje dijelovi transportnog modula moraju zadovoljavati kako bi uopće mogli obavljati funkciju u prehrambenoj industriji. Dan je kratki opis tehnoloških operacija koje su potrebne za izradu dijelova transportnog modula. Nadalje, navedeni su strojevi pomoću kojih je moguće izraditi te dijelove, odabrani su suvremeni rezni alati kojima se smanjuje vrijeme obrade, a povećava kvaliteta izrade dijelova transportnog modula. Na temelju odabranih alatnih strojeva i reznih alata projektiran je tehnološki postupak izrade za okretni usmjerivač transportnog modula, sa svim parametrima obrade. Kako je okretni usmjerivač transportnog modula u osnovi savijena i zavarena konstrukcija većih dimenzija, na nju se zavaruju i montiraju ostali dijelovi čime ona postaje funkcionalna cjelina. Zbog svoje veličine i strogih tolerancija javlja se problem kod stezanja okretnog usmjerivača transportnog modula na stol stroja. Da bi se zadovoljile stroge tolerancije konačnih dimenzija razrađeni su i prikazani načini stezanja pomoću standardnih steznih elemenata , te na mjestima gdje nije moguće koristiti standardne stezne elemente, izrađena je specijalna stezna naprava. This paper elaborated the technology of parts of the transport module that is used for transportation of products in the food industry. The paper lists the conditions, laid down by the European groups of hygienic engineering and design, which parts of the transport module must meet in order to even be able to perform the function in the food industry. There is a short description of technological operations that are required for parts of the transport module being made. Furthermore, the machinery by which it is possible to make these parts are listed, modern cutting tools are selected to reduce processing time and increase the quality of production of parts of a transport module. Based on selected machines and cutting tools, technological process of making the rotating router of transport module is designed, with all processing parameters. As the rotating router of transport module is essentially bent and welded construction of larger dimensions, other components are welded and assembled on it making it a functional unit. Because of its size and strict tolerances, there is a problem when holding the rotating router of transport module on the machine table. In order to meet the strict tolerances of the final dimensions, there were developed and shown ways of tightening using standard clamping elements, and on places where it is not possible to use standard clamping elements, a special clamping device is prepared.

Tema ovog diplomskog rada je prilagodba robota za glodaći ispitni postav, tj. potrebno je prema robotu ABB IRB 6400 koji se nalazi u Laboratoriju za alatne strojeve, Fakulteta strojarstva i brodogradnje u Zagrebu konstruirati prijenosno postolje te prihvatnicu za motorvreteno koje će se montirati na ruku robota. U prvom, uvodnom dijelu prikazat će se što je ustvari robotika i koji je njezin značaj u suvremenom svijetu i proizvodnji. Nadalje opisat će se povijest i razvoj robotike te pojava prvog industrijskog robota u 20. st. Treće poglavlje pojašnjava podjelu robota na više načina: prema vrsti pogona, geometriji radnog prostora i načinu upravljanja gibanjem. Četvrto poglavlje opisuje primjenu robota u industriji, dok peto poglavlje opisuje ABB robote, njihovu povijest i primjenu. U šestom poglavlju prikazana je izrada postolja te potreban proračun sila i naprezanja. Sedmo poglavlje donosi opis motorvretena te izradu prihvatnice za motorvreteno u svrhu prilagodbe robota za glodaći ispitni postav. Potrebna dokumentacija za izradu prijenosnog postolja izrađena je u programu ''CATIA'' i ''AutoCAD'' The theme of this diploma work is an adaptation of robots for milling testbed, ie. it is necessary on the basis of the robot ABB IRB 6400 located at the Laboratory for Machine Tools, Faculty of Mechanical Engineering and Naval Architecture in Zagreb, to construct a mobile stand and a catch for spindle motor which will be mounted on the robot arm. In first section it will be shown what robotics actually is and its significance in the modern world and production. Furthermore, the history and development of robotics and the emergence of the first industrial robot in the 20th century will be described. The third section discusses the division of robots in several ways: by type of the drive system, the geometry of the work area and the method of motion control. The fourth chapter describes the application of robots in industry, while the fifth chapter describes the ABB robots, their history and use. The sixth chapter shows the development of the stand and the required calculation of the forces and stresses. The seventh chapter provides a description of spindle motor and the making of the catch for spindle motor for robot adaptation for milling testbed.

U današnje vrijeme, s porastom upotrebe visokih tehnologija u svim aspektima ljudskog života, sve je učestalije korištenje raznih aparata koji se koriste za direktnu ili indirektnu prodaju proizvoda. Govoreći o proizvodima, oni mogu biti u fizičkom obliku kao proizvodi za svakodnevnu primjenu ili vrsta usluge koje korisnik može dobiti kroz uređaj i njegove funkcije. Samoposlužni aparati dio su multi-biljunske industrije dolara. Dizajnirani su novi aparati koji prodaju luksuzne proizvode i elektronike, te se razvijaju veliki aparati koji bi se koristili za samoposluživanje ili maloprodaju. Aparati su prošli kroz značajne promjene i inovacije. Mnogi samoposlužni aparati razvijaju prihvaćanje kreditnih kartica, a tvrtke su sada u mogućnosti pratiti stanje nekog aparata iz daljine. U diplomskom radu opisan je samoposlužni uređaj koji služi za direktnu prodaju proizvoda u fizičkom obliku, odnosno žvakaćih guma, kroz koji korisnik, plaćajući na samom uređaju, može dobiti željeni proizvod po uplati, bez uplitanja ljudske osobe koja bi, kao što je uobičajeno, izvršila kupoprodaju. Za samoposlužni aparat za žvakače gume bilo je potrebno istražiti zahtjeve tržišta te način rada samoposlužnih uređaja. Projektiran je i konstruiran mehanički dio uređaja, te su odabrane elektroničke komponente kojima se ostvaruje funkcija samoposlužnog aparata. Određena je cijena i primjena uređaja, te je izrađena potrebna dokumentacija za njegovu izradu. Nowadays, with increased use of technology in all aspects of human life, all the more frequent is the use of various devices for direct or indirect sale of a product. In regards to the products, they can be in physical forms such as products for everyday use or the type of services that the user can get through the device and its functions. Vending machines are part of a multi-billion dollar industry. Machines are designed to sell everything from luxury goods and electronics, with larger devices developing that could be used for self-service or retail purposes. Devices have undergone significant changes and innovation. Many developing vending machines are accepting credit cards and companies are now This thesis describes vending machines that are used for direct sale of products in physical form, i.e. chewing gum. The user, by paying on the device itself, can get the desired product directly after payment without the interference of a human throughout the transaction. For a vending machine dispensing chewing gum it was necessary to explore the market requirements and demands, as was the operation of the actual vending devices. The mechanical components were projected and constructed, as was the selection of the electrical parts that provided the functions of the self-service machine. The cost and application of the device were also determined and the necessary documention for its development was also devised.

Čovjek je drvo koristio od svog postanka, a i danas je jedan od najšire upotrebljavanih prirodnih materijala. Industrijskim razvojem drvna industrija često je glavni oslonac izvoza i time izvor prihoda za privredni razvitak. U današnjem modernom svijetu sve je učestalija potreba za bržom i preciznijom izradom drvenih gravura i reljefa. Postojeći strojevi na tržištu za takve obrade imaju dosta veliku cijenu. Obzirom da ovdje nisu prisutni pretjerani zahtjevi za točnošću, ideja je da se od postojećih gotovih kupovnih modula konstruira alatni stroj koji udovoljava zahtjevima, a nije pretjerano skup. U prvom dijelu rada prikazan je literaturni pregled postojećih strojeva za obradu drva. U drugom dijelu rada prikazan je primjer proračuna i odabira konstrukcijskih i energetskih dijelova stroja te je predloženo idejno rješenje konstrukcije CNC glodalice za obradu drva. Model konstrukcije stroja izrađen je u softverskom paketu CATIA, a na kraju je prikazan izračun cijene predloženog konstrukcijskog rješenja. The wood was one of the first materials man used, and even today it's one of the most commonly used natural materials. Industrial development of the timber is often the mainstay of exports, and thus a source of revenue for economic development. In today's modern world there is a common need for faster and more precise production of wood engraving and relief. The existing machines in the market for such processing have quite a high price. Since here are not present excessive demands for accuracy, the idea is to construct from existing modules a CNC machine for wood engraving that meets the requirements, and not overly expensive. In the first part of this work is a literature review of existing wood processing machinery. The second part presents the example of the calculation and selection of construction and energy components of the machine and the proposed conceptual design construction of CNC router. The structural model of the machine is made in the software packag CATIA, and finally calculation of the proposed construction is proposed.

U diplomskom radu se konstruira, opisuje izrada i ispitivanje steznog alat, koji služi za vanjsko stezanje prstenastih obradaka na amerikaneru. Osnovni cilj steznog alata je realizacija proizvodne operacije koja se dobiva ispravnim pozicioniranjem obrađivanog predmeta, čime se smanjuje pojavljivanje grešaka obrađivanog materijala, tj. „škarta“. Potreba za konstruiranjem novog steznog alata proizašla je iz razloga, što se stezanjem obradaka starim steznim alatom vrlo često dobila deformacija obradaka. Novim načinom stezanja obradaka bi se povećavala produktivnost alatnih strojeva ali i sigurnost obrade. U radu je razmatran novi stezni alat za prstenaste obradke od njegovog konstruiranja pomoću računalnog programa AutoCAD, do same izrade, te ispitivanja ispravnosti steznog alata na alatnom stroju. In the graduate work is constructed, and described the development and testing of the clamping tool, which is used for external clamping of workpiece rings on jaw chuck. The main objective of the clamping tools is the realization of production operations which is obtained in the correct positioning of the processed workpieces, thus reducing the appearance of defective workpieces.The need for constructing new clamping tools is derived from reason, which is clamping workpieces with old clamping tools gives often distorted workpiece. A new way of clamping the workpiece is increased productivity of machine tools and will be increased security of process. In the graduate work is presented a new clamping tool for circular workpieces and its designing by a computer program AutoCAD, to the process of making and testing the correctness of the clamping tools on machine tools.

Alate za obradu provrta kao jedne od najzastupljenijih operacija obrade odvajanjem čestica u proizvodnoj industriji potrebno je unapređivati. Svi svjetski proizvođači alata za obradu provrta rade na tome da se smanji vrijeme obrade, poveća kvaliteta obrađene površine, a samim time i poveća sveukupna produktivnost. Suvremeni rezni alati za obradu provrta prate taj trend tako da danas na tržištu postoji jako veliki broj alata raznih proizvođača za operacije obrade provrta. Hole making tools are used for one of the most common machining operations in manufacturing industry and they are improved constantly. All cutting tools manufactures in the world improve hole making tools in that way so the cutting time is reduced and surface finish is improved, what leads to improved overall productivity. The modern cutting tools for hole making follow this trend, so today there is a large number of tools from various cutting tools manufacturers on the market.

Navoj je geometrijsko tijelo koje ima široku primjenu u svim granama strojogradnje, ali i svakodnevnom životu. Najčešća vrsta spojeva su vijčani spojevi čiji osnovni elementi, vijak i matica, upravo preko navoja ostvaruju potrebnu vezu. Vijčani spojevi imaju više uloga, kao što je spajanje dijelova, pretvaranje rotacijskog gibanja u translacijsko, podešavanje ili brtvljenje. Navoj ima svoje osnovne karakteristike kao što su promjer, korak, profil i vojnost. Postoji više vrsta navoja, a najčešći je metrički navoj s teorijskim profilom jednako straničnog trokuta. Navoj je moguće izraditi na više načina; glodanjem, urezivanjem, narezivanjem, deformiranjem, brušenjem, a najčešći način izrade je tokarenje koje pokriva široki spektar navojnih profila. Svaki način izrade ima svoje prednosti i nedostatke, tako da se način izrade odabire prema potrebama površine navoja, veličini serije te dostupnim alatnim strojevima i reznim alatima. Prilikom svake obrade moguća je pojava grešaka, koje je važno prepoznati te uz pomoć znanja i iskustva ukloniti u što kraćem vremenskom roku da se izbjegnu zastoji i pojava škarta. Thread is geometrical object which is widely used in every aspect of engineering and daily life. The most common type of joints are screw joints which basic elements, a screw and a bolt, are connected by thread. Screw joints have more functions such as joining parts, converting rotational into translational movement, adjusting and sealing. Thread has some characteristics such as a diameter, pitch, profile and number of starts of the thread. There are several types of thread, and the most common type is metrical thread with theoretical isosceles profile. The thread can be made in many ways; by milling, tapping, dieing, forming, grinding, but the most common way is turning which enables making many types of thread profiles. Every method has advantages and disadvantages, so the surface quality demands, number of parts and availability of machines and equipment determines the method that will be used. There is always a possibility of an error during thread making, which is important to recognize and fix as soon as possible by using knowledge and experience to avoid delays and incorrect parts.

Foundries striving to accomplish defect free castings and to optimize their production regularly use numerical simulation software as a key part of technological casting preparations. In this way great reduction in excessive material, energy and time consumption is achieved. As a result of collaboration between Faculty of Mechanical Engineering and Naval Architecture (UNIZAG FSB) and RS Metali d.o.o. we were able to make a casting and solidification simulation for a flange that was made of EN-GJS-400-15 ductile iron. In addition to currently used designs two more gating and risering systems were created for the same flange at UNIZAG FSB. Additional simulations in software ESI QuikCAST® were executed which showed improvement of cast quality and efficiency of production.

Because of the increased need for the new technologies in machining, there is a need for mutual cooperation of experts in the field of mechatronics and machining. The fact is that there is a large share of old machines in the surroundings of Bjelovar, but also the entire Croatia, that are very precise, but have very low productivity (bad control unit). Example of cooperation [1] equipment manufacturer (Siemens), higher education institution (Technical College in Bjelovar), manufacturing companies in Bjelovar and the surrounding area, as well as timely involvement of students in the whole process of work [2], it is considered that it is possible to make a significant step forward in terms of this segment of the Croatian economy.

Production of small cylindrical parts from electrical conductive materials, which are difficult to machine by a conventional cutting method can be achieved with Cylindrical Wire Electrical Discharge Turning process (CWEDT). The main application disadvantage of CWEDT process is amount of time necessary for part production in comparison to conventional machining. Therefore large majority of the CWEDT process research deals with identifying the highest process factor levels to increase material removal rate (MRR). Experimental procedure and observations for determining research solution field is shown. The process parameters levels are determined which value change can improve stability of process. Early detection of process irregularity is done by electric pulse monitoring. Conclusion has been made about role of machine servo feed on process stability, together with influence of process parameters on irregularity phenomena.

This paper gives a review of the development of the coolant and lubricant systems, starting from the classic ones, which are used in the machining, and then it deals with both the dry processing and the alternative methods of cooling during the machining. The influence of coolants and lubricants on the environment and the people's health is emphasized as well as the implementation of cooling with cold compressed air. Cold compressed air can replace the function of classic coolants and lubricants during the cooling of both tool and machining parts, and also on the cooling of the chips and their elimination from the machining area. The vortex tube is mostly used in cold compressed air cooling, which enables the separation of hot and cold air during the flow of compressed air across the incoming nozzles tangentially into the vortex chamber.

In this paper the influence of heat treatment in coarse – grained (CG HAZ) and in fine – grained heat affected zone ( FG HAZ) had been tested on P91 steel. The steel is intended for work in higher temperatures in heat plants. Heat treatment after welding is needed since welding significantly lessens mechanical properties, including toughness. Results have shown that heat treatment on temperature of 760 °C over 2 hours has a good effect on mechanical properties as a result of hardness decrease. Research has been done on samples simulated on the heat cycles simulator Smitweld TCS 1405.....

In general, one of the main casting defects due to residual stresses are cracks (tears). Cracks may be defined as a material separation, which is caused by mechanical and dynamic overloads. There are cold and hot cracks, depending on the temperature range in which they occurred. Hot cracks (tears) represent intercrystalline material separations that form in the solidification interval, just above the solidus temperature. They are caused by the residual stresses in the casting and the insufficient ability of material to bear such stresses. An analysis of possible patterns and mechanisms of hot tear formation during casting in operating conditions is presented in this paper.

High market demands that is oriented to the manufacturing of complicated products within short time at low cost have led to the increasing application of additive manufacturing, especially for small or individual series. These technologies can assist in identifying the basic mistakes that are expensive to correct if they are detected when the product has already started.However, parts are not cheap, and decision how to produce them to obtain maximum benefit, sometimes is difficult. Besides of the cost of materials also the cost of machine and postprocessing plays a significant role in the price of the produced part. Recently low-budget machines appear on the market. Those machines are mainly based on Fused Deposition Modeling (FDM). For each additive process, because of its advantages and disadvantages it is necessary to design a particular product to obtain maximum benefit of the procedure and the available machine. In this paper it is shown some principles how to design and produced housing with fused deposition modeling.

15th International Scientific Conference on Production Engineering CIM 2015, will take place from 10-13 June, in Vodice – Croatia, as a traditional event organized by the Croatian Association of Production Engineering (HUPS) in the co-operation with the PTW Institute of Technical University of Darmstadt. Our intension is to preserve a spirit of CIM conferences, manifested through scientific, expert and social aspect. We are positive that beauties of Vodice, national parks Kornati, Krka and Paklenica could only contribute to friendly atmosphere of CIM conferences. Computer integrated manufacturing (CIM) and high speed machining belong to the main development directions in production engineering. The continuity of interest for the CIM conference confirms on actuality of papers and their importance for science and industry. The main objective of the Conference is to provide a possibility for the presentation of scientific and professional achievements, and also to give an overview on the state of the art and development trends in production engineering, advanced technologies and manufacturing. The Conference also aims at giving its participants an opportunity to update their knowledge, to become acquainted with the latest products and also to take a look at the future. In addition, the Conference will serve as a platform for sharing knowledge, ideas and results between science and industry. CIM 2015 is 13th Conference organized by HUPS and PTW Institute of Technical University of Darmstadt. HUPS was found in 1992 in Zagreb, with the objective to organize and promote the scientific, professional and teaching activities in the field of production engineering. PTW is one of the world leading institutions in the field of high speed machining. For this successful collaboration we have to thank to Prof.Dr.Ing. Herbert Schulz, recognized scientist in this field, and to Prof.Dr.Ing. Eberhard Abele, director of PTW Institute. Special gratitude and respect we pay to Prof. Roko Cebalo, Ph.D., HUPS founder and longtime president, who started this cooperation and successfully ran it until he passed away on 5th of August 2008. The Review committee accepted 40 scientific papers for this conference, 11 among them from abroad. The majority of papers from Croatia are the result of scientific projects initiated and funded by the Ministry of Science, Education and Sport, to whom we would like to express our sincere gratitude. Wishing to strengthen the importance of cooperation between industry and academy, CIM 2015 will be enriched by the workshop. This half-day workshop will bring together well-known partners participating in the field of power generation: ALSTOM, WALDRICH COBURG, UnionChemnitz, GEORG, WALTER, IPS Systemtechnik, HSTec, ELB & ABA. They will present their valuable experiences, knowledge and various approaches, bringinng higher efficiency and improvements in the field of MACHINE TOOLS FOR COMPETITIVE AND SUSTAINABLE MANUFACTURING. Finally, let me once again to thank you for your participation in this conference and to sincerely welcome you on behalf of the organizing committee of CIM 2015.

U radu je prikazan proces konstruiranja 4-osne numerički upravljane glodalice za obradu polimernih pjena. Polimerne pjene su relativno jeftin i lako obradljiv materijal s dobrim mehaničkim svojstvima zbog čega se koriste za izradu raznih ortopedskih pomagala i medicinskih implantata. Na glodalici je predviđena obrada dijelova sličnih pojedinim dijelovima ljudskog dijela, npr. torzo. Za obradu takvih površina dovoljne su četiri numerički upravljane osi od kojih su tri translacijske i jedna rotacijska. Rotacijska os je ostvarena s okretnim stolom. Prvi korak u ovom radu je proračun osnovnih dijelova stroja, a to su kuglično navojno vreteno, pogonski servo motor, linearne vodilice i reduktor okretnog stola. Nakon toga je cijela glodalica modelirana u CAD programu „CATIA“. Da bi glodalica potpuno ispunila svoju funkciju, modelirani su i neki konstrukcijski dodaci kao što su šiljak, protuuteg, kutija za odvojenu česticu i zaštita za operatera. Potrebna dokumentacija za izradu stroja izrađena je u programu „AutoCAD“. In this thesis a designing process of an 4-axis CNC milling machine for machining of polymeric foams is shown. Polymeric foams are relatively inexpensive material with high machinability and good mechanical properties. Because of this propertis they are used for making various orthopedic devices and medical implants. The milling machine is designed for milling parts identical to certain parts of human body, such as torso. For milling such surfaces four numerically controlled axes are sufficient, three translational and one rotational. The rotational axis is achieved by the rotary table. The first step in this thesis is the calculation of the basic parts of the machine, such as ballscrew, servo motor drive, linear guideway and gearbox rotary table. After that, the entire milling machine is modeled in CAD software "CATIA". To achieve the complete function of the milling machine, some constructional extras such as spike, a counterweight, a box for a separate particle and protection for the operater were modeled. The necessary documentation for making the milling machine is made in the „AutoCAD“ software.

The recycling or reuse of material in production becomes as a saving task for sustainable and environmental competitive production. Sustainability means not only achieving cost efficient process but also eco efficient. It is well known that water jet (WJ) technology use natural resources (water and abrasives), has low thermal influence on workpiece and at the same time cutting has been achieved with high energy concentrated process which offers many objectives of multi efficient manufacturing. This work evaluates the applicability of reused abrasives in WJ cutting process. Recycled abrasives are tested to achieve similar rates of productivity and cut quality as the new one. Different conceptual solutions of recycling equipment confirm the importance of life cycle management of abrasives in enabling of green manufacturing.

Development of new product is particularly complex because it involves understanding many areas of design, from an aesthetic design to knowledge of mechanical and product properties. Also specialty polymer materials and their processing presents difficulties in the development of the product itself. Nowadays, additive manufacturing is, especially for small series, increasingly replacing classical processing. As a key element in the production of products with additive manufacturing it is necessary to have computer model (ie, knowledge of modeling in the 3D software). In case of already having the product produced with classical processes without the necessary documentation or in the case of complicated geometry of the products scanning and reverse engineering can be used. With reverse engineering it is possible to reach optimal design, reduce the cost and time necessary for launching of products on the market. In this paper scanning, reverse engineering and additive production is shown on the cover for smartphone.

This paper describes in detail the construction, implementation and navigating of the low-cost robotic arm with five degrees of freedom movement for the purpose of the educational mobile robot eMiR [1]. In accordance with the working conditions applied on the mobile robot, all the elements of the robotic arm were constructed using CAD program tool [2], and they were made using a low-cost 3D printer (FDM procedure) [3]. Raspberry Pi is used as the control unit of the robotic arm [4], and as driving elements DC servo motors were used [5]. The navigation program and the kinematic robot model were made in an open- source environment [6] and are also described in the paper. The performance of the overall system was tested on two basic movement

For seismic areas, with frequent and extremely high earthquake amplitudes, it is necessary to perform stress calculation for the evaluation of structure safety. Equipment and its parts have to be functional and manufactured with optimal costs. Based on the calculated values, estimation is performed whether welded joints on equipment parts need any additional prefabrication or heat treatment during and after the welding. Result of such analysis is the saving of material and time for manufacturing. The paper presents calculation and strength verification of steel structure for the foundation of Fuel Gas Block. Fuel Gas Block is extremely important equipment due to explosive media and it must be designed and manufactured to satisfy maximum safety conditions

The research within project Innovative Smart Enterprise wants to improve the scientific understanding of the current state of Croatian manufacturing industry by promoting empirical, enterprise-level research on technological and non-technological processes and organizational innovation. The aim is to understand how manufacturing enterprise in Croatia acquire new manufacturing technologies, ICT integration within processes, new organizational concepts in production such as group work or relocation of production, new products that emerge from process and organizational innovation such as production-related services, and other demands related to Industry 4.0. Research has been made using Web questionnaires and interviews with CEOs and/or technical directors of manufacturing enterprises in Croatia. The aim was to gather the data from large number of enterprises. The questionnaires consisted of questions which completely describe one enterprise. Analysis and conclusions on the current state of Croatian manufacturing industry are based on the responses of 159 enterprises from Croatia.

An increase in the production of micro-components causes a need for the development of appropriate manufacturing techniques, one of which is deep-micro-hole-drilling. This paper presents the development of an adaptive machining system for deep micro hole drilling whereby adaptive control is recognized through thrust force. The drilling of 0, 5 mm diameter holes in special cast irons with up to 40:1 depth to diameter ratio is performed. Due to the problems related with micro hole drilling in respect to conventional drilling and expressive heterogeneity of workpiece materials, it is shown that the use of an adaptive control can be of significant improvement for insurance of an adequate micro drilling process.

The work carried out some analysis microforming. Microforming in metal forming the production of small dimensions in at least two axes not exceeding 2mm. Technology is microforming differs in many ways from the conventional technology of metal forming. It is well recognized that expertise, experience, and theoretical knowledge available in conventionally sized metal forming cannot be simply transferred to microforming. This is due to so-called size effects which have distinct effect on material flow, friction and other process characteristics. Today, process simulation is a standard tool in industry, applied to support process lay-out and its optimization. However, as it is based on continuum mechanics, it is size-invariant at least for cold forging. Hence, it is obvious that due to the size effects, conventional simulation cannot be applied to microforming. In this paper two approaches are presented how to model specific phenomena of microforming in particular concerning material flow and friction. These are the mesoscopic model and a combination of the general friction law and mechanical rheological model, respectively. Both models are brought together to be finally applied to a combined micro cold-extrusion process.

Mobile robots take a great part in the robotics research space. Today researches are carried out in the area of robot design, robot control, interaction between a robot and its environment, path planning, sensors, etc. The least researched problem in the area of mobile robots is related to robot programming languages. Most programming languages for mobile robots are oriented to robot movement, not to the robot goal. It means that the programmer explicitly defines the robot kinematics (position, velocity, orientation) which works fine in a well-defined environment, but it is limited in flexibility and is not user-friendly. This paper describes the research that has a goal to define a minimal set of robot commands that would enable flexible control of the robot in a poorly defined environment. Robot commands are task- oriented rather than kinematics-oriented. To enable the goal of task orientation, a vision system mounted on the robot is used besides internal robot sensors (encoders, range finders and timers). Vision system is a separate application that recognizes objects by their color and sends information to the program for the robot control. All algorithms for the object recognition and robot control are tested using the eMIR mobile robot that works within an appropriate environment.

Herein, a simple semi-empirical approach to the modelling of cutting force, which is based on the shearing and ploughing theory, is proposed and experimentally validated for a turning operation. The cutting force components acting on the nose radius tool were estimated by dividing the uncut chip area into small segments. The local forces acting on each segment have been calculated and the total cutting force components were then determined by summation of the respective local forces. Estimated cutting force components have been compared to measured ones and their good agreement was observed.

An alpha field is the field that can be described by two dimensionless field parameters α and α'. A quantum alpha field is the alpha field in which quantum effects can be occurred. In classical mechanics, a nanorobot has, at every moment, an exact position and an exact momentum, following the Newton’s laws of motion. In quantum mechanics, nanorobots do not have exactly determined properties and when they are measured, the result is randomly drawn from a probability distribution. The classical approaches to control of nanorobot motion in the multipotential field have been presented in the authors previous papers. In this paper we continue to investigate the related control algorithms for a nanorobot motion in a quantum alpha field. In that sense the nanorobot dynamics has been described by the Schrödinger equation in an alpha field that predicts what the probability distributions are. Meanwhile, it cannot fundamentally predict the exact result of each measurement. Thus, the problem is: how to control of a nanorobot motion in the case when quantum effects are occurred. Some approaches are discussed in this paper.

Final machining of 34CrMo4 steel with roller burnishing tools is shown in this paper. Roller burnishing process is clean and environmentally friendly machining process which can replace other finishing processes with pollution effects. Experimental tests on specimens prepared for final machining process estimates the rate of roughness decrease, and diameter increase. Roughness data measured before and after roller burnishing process have been compared. Roughness ratio (before/after process) and decrease factor for surface quality improvement can be up to 10. Presented smoothing process can be performed on standard machine tools without additional reconfiguration tasks. Process is very versatile for any workshop and can be conducted without coolant.

Paper presents investigation of weldability of S960QL steel on specimens after weld thermal cycle simulation and on real welded specimens. Beside mehanical properties and chemical composition of base metal steel S960QL, authors gave results of hardness on simulated and real welded specimens and impact toughness data for different points in heat affected zone on weld thermal simulated specimens.

Within teaching classes in professional courses in the study of mechatronics and project of student enterprise-technology incubator at the Technical College in Bjelovar, we set a goal of improving conditions to upgrade teaching and to implement projects based on knowledge and new technologies for connecting with economy. The needs of the manufacturing - enterprise sector in Bjelovar, in the region, and even wider were taken into consideration.

14th International Scientific Conference on Production Engineering CIM 2013, will take place from 19-22 June, in Biograd – Croatia, as a traditional event organized by the Croatian Association of Production Engineering (HUPS) in the co-operation with the PTW Institute of Technical University of Darmstadt. Our intension is to preserve a spirit of CIM conferences, manifested through scientific, expert and social aspect. We are positive that beauties of Biograd, national parks Kornati, Krka and Paklenica could only contribute to friendly atmosphere of CIM conferences. Computer integrated manufacturing (CIM) and high speed machining belong to the main development directions in production engineering. The continuity of interest for the CIM conference confirms on actuality of papers and their importance for science and industry. The main objective of the Conference is to provide a possibility for the presentation of scientific and professional achievements, and also to give an overview on the state of the art and development trends in production engineering, advanced technologies and manufacturing. The Conference also aims at giving its participants an opportunity to update their knowledge, to become acquainted with the latest products and also to take a look at the future. In addition, the Conference will serve as a platform for sharing knowledge, ideas and results between science and industry. CIM 2013 is 12th Conference organized by HUPS and PTW Institute of Technical University of Darmstadt. HUPS was found in 1992 in Zagreb, with the objective to organize and promote the scientific, professional and teaching activities in the field of production engineering. PTW is one of the world leading institutions in the field of high speed machining. For this successful collaboration we have to thank to Prof.Dr.Ing. Herbert Schulz, recognized scientist in this field, and to Prof.Dr.Ing. Eberhard Abele, director of PTW Institute. Special gratitude and respect we pay to Prof. Roko Cebalo, Ph.D., HUPS founder and longtime president, who started this cooperation and successfully ran it until he passed away on 5th of August 2008. The Review committee accepted 42 scientific papers for this conference, 13 among them from abroad. The majority of papers from Croatia are the result of scientific projects initiated and funded by the Ministry of Science, Education and Sport, to whom we would like to express our sincere gratitude. Wishing to strengthen the importance of cooperation between industry and academy, CIM 2013 will be enriched by the workshop. This half-day workshop will bring together well-known partners participating in the field of power generation: ALSTOM, WALDRICH COBURG, DMG MORI SEIKI, WALTER, LEISTRITZ, RETROFIT VERBUND. They will present their valuable experiences, knowledge and various approaches, bringinng higher efficiency and improvements in the field of MACHINE TOOLS FOR COMPETITIVE AND SUSTAINABLE MANUFACTURING. Finally, let me once again to thank you for your participation in this conference and to sincerely welcome you on behalf of the organizing committee of CIM 2013.

Rotor of turbines, generators, electric motors and similar machines, besides their purpose, have to satisfy the requirements for the safe and reliable operation. To ensure these requirements, rotors during manufacture with a number of manufacturing operations must be balanced to the required quality. Position and rotor unbalance is determined on the balancing machine. Adding or subtracting a certain mass reduces unbalance. However, some rotors can only be balanced by their deformations in relation to the axis of rotation, which is realized by selective heating of surfaces. This procedure introduced local stresses, which deform the rotor relative to the axis of rotation. Temperatures and size of the area, except the unbalance, depend on the design and material of rotor. In this paper, finite element analysis and results of temperature and stress calculation for two examples of the heating process are presented. The first is an example of the rotor of thin-walled tubes. The second is the alignment of the deformed compact rotor. Both examples are successfully applied in practice.

With additive manufacturing it is possible to create products with complicated geometry from 3D data in very short time, which is very difficult or even impossible to do with other manufacturing technologies. However, there are many limitations, primarily in the selection of plastic materials and available colours. Also the problem occurs for different additive processes in the appearance of the final surface.Thus, the process selective laser sintering – SLS uses plastic powder that gives a high surface roughness and products can be made only in one colour – white. The paper will provide a brief overview of SLS, processes of colouring and different surface treatment of polyamide products made by SLS after surface treatment and without it.

Simulation helps to understand filling and solidification process, optimization of new dies and casting parameters. Paper was done in cooperation with Lama d.d. company from Dekani, Slovenia. Numerical simulation of die casting process of zinc alloy Zamak 5 was investigated in order to determine the process parameters which assure expected quality of the casting. Hot chamber die casting process was modelled and simulated. Software ESI ProCAST was used as a tool for virtual process simulation. Obtained results of simulation agree with experimental results. Simulation may be used for optimization of hot chamber die casting. It leads to more economical production with better quality of castings.

The strength of the European economy are Small and Medium-sized industrial Enterprises (SMEs). However, the global economic crisis has compromised their normal business flow. The solution is often seen in their mutual networking in highly flexible Virtual Enterprises. Thus, this paper deals with the Virtual Enterprise formation process. In that process it is necessary to determine which enterprise to choose, with what characteristics and according to which criteria. It is obvious that the Virtual Enterprise formation process requires the use of multi-criteria decision-making, i.e. use of methods for multi-criteria analysis and decision-making, methods like PROMETHEE method.

Huge competition and continuously changing globalized market demands require constant change and improvements of company’s business. The philosophy of Lean production offers a wide variety of advantages for production system improvements. Lean production concept is understood as the realization of Lean principle through the efficient application of methods and tools, with faster and more effective discovering of wastes and mistakes in the production systems. This article contains a presentation of modified Lean tool, Value Stream Mapping, application, on power transmission casings production. Designed future state according Lean principles showed improvement opportunities and lead time reduction despite high product mix.

In this paper, parallel Levenberg-Marquardt-based feed-forward neural network with variable weight decay, implemented on the Graphics Proce-ssing Unit, is suggested. Two levels of parallelism are implemented in the algorithm. One level of parallelism is achieved across the data set, due to inherently parallel structure of the feed-forward neural networks. Another level of parallelism is achieved in Jacobian computation. To avoid third level of parallelism, i.e. parallelization of optimi-zation search steps, and to keep the algorithm simple, variable decay rate is used. Parameters of variable decay rate rule allow for compromise between oscillations and higher accuracy on one side and stable but slower convergence on the other side. To improve training speed and efficiency modification of random weight initializa-tion is included. Testing of a parallel algorithm is performed on two real domain benchmark problems. Results, given in a form of a table with obtained speedups, show the effectiveness of proposed algorithm implementation.

In this paper, the procedure of 3D scanning of turbine blade using structured light method is described. Dimensional control is conducted comparing 3D scan with CAD model of the object. Conducted processes of 3D scanning and measurements show advantages over traditional measurement techniques using coordinate measurement machines, in respect to time usage, amount of collected data and flexibility of the measurements.

Modern grinding spindles are increasingly dynamically loaded and due to constant growth of accuracy and surface quality demands, they have to be more rigid. Because of that, it is important to make an optimal selection of the type and configurations of a bearing set. There are special requirements on balancing all rotational parts not only before the assembly but also during the drive and process phase. This work analyzes the effects of balancing and bearing set configuration on the vibrational behavior of the grinding spindles. Great amount of attention is dedicated to the temperature stability because of higher accuracy, grinding quality and the lifetime of the grinding spindle. This work presents calculations and measurements on the grinding spindle with the different type of bearing set configurations.

Beside appropriate heat treatment parameters, conditions of heat treatment and appropriate process conduction have important influence on materials properties. In this paper the influence of austenitizing time and protective atmosphere on properties of 42CrMo4 steels are investigated. Heat treatment was conducted in chamber furnace without protective atmosphere and with argon protection. After austenitizing on 850°C in time of 5 and 25 minutes the specimens were quenched into room temperature oil. After the heat treatment, appearance and hardness of the specimens are analyzed.

Porosity belongs to one of the main factors regarding quality of the products in casting industry. Porosity in some degree is always present, has bad influence on quality of the surface of the casting, its mechanical properties and resistance to corrosion. Hydrogen as the only gas capable to solve in significant quantities in aluminum melt is the main factor influencing gas porosity. Due to thorough establishment of quantities of dissolute gas in the castings, the paper examines the influence of vacuum on the occurrence of porosity during casting of aluminum alloys.

Paper describes how CAD programs (CATIA V5) are used in production of the Gas Turbines components – Compressor Vane Carrier 2, in engineering, technology and manufacturing department. People from this departments share the same basic geometries and solids in the production process. It will be visible process from engineering to technology and final, manufactured components in production. Catia V is program for parametric design ; therefore, some changes made in engineering department can be very fast modified and prepared for further work in technology. The result of applying CAD (Catia V5) models is shorter processing time, reduction of clash in turbine assembly, cost reduction and shorter delivery time of the gas turbine components.

The trend of miniaturization of components in modern industries like aerospace, automotive, medical, and electronic industries creates a strong demand for manufacturing techniques involving micro features such as micro holes. This paper presents the design of a machining system for deep micro holes (hole diameter of up to 1 mm, length and diameter ratio from 15 up) in order to increase the productivity and ensure the stability of the process. A machining system including vibration assistance (VA) in the longitudinal direction is developed as a method for reducing machining forces and torque, chip size, burrs, tool wear and breakage. The system can be extended with monitoring devices and various types of polishing can be combined in order to improve the roundness and final tolerance of bores.

The paper is concerned with the choice of optimal machine characteristics, and influence of heating metal of the sheets on the effects of energy management, environment protection, and process characteristics. Sheet metal mechanical properties change as a function of temperature, rate of deformation, speed of deformation, etc. Highest influence on mechanical properties of sheet metal during metal forming has temperature. Material changes its properties with temperature which is described with flow curves determined at different temperatures. Bending process parameters such as force and calibration force in plate bending are very important. Calibration force is determined when bending force and calibration coefficient are known. Significant factors for determination of bending force for circular plate are: the material of the circular plate, bending radius of the circular plate, diameter of the circular plate, thickness of the circular plate and method of loading of the circular plate. The calibration coefficient is determined by experiment.

Paper describes the use of published geometries , published bodies (solids) and MML (multi model links) in the design process with CATIA V5 CAD program for design of Steam turbine components, like turbine casings used in the steam turbine modules. It assists the designer in creating Product Components, which are all producible parts. The modelling process describes how a Product Component has to be created in context "symmetric" and "non- symmetric" machining. In the case of Machined Parts all machining operations have to be designed with negative features using some rules needed for NC-programming what will be described in the paper. The result is a shortening of processing time, cost reduction and shorter delivery time of turbine modules.

This paper gives an overview of the machining technology applied in impeller production. The complex geometry of the impeller (thin walls combined with interrupt cutting condition) and the tolerance demands make this production challenging. Raw material was casted duplex steel X2CrNiMoN 26 7 4 (W.Nr. 1.4469) with high content of Mo. During the casting process of duplex steel it is necessary to ensure high purity of melts, as well as a small scattering of alloying elements. The problem facing this production was impurity (sand) on the impeller blades. Before the machining, the impurity has to be removed by milling or grinding and after that filled with welding technology. TIG process, with wire thickness of Φ=2.4mm was performed. Before welding it is necessary preheat the material up to 120-150 ˚C.

CNC plasma cutting machine is designed and modeled within this paper. Drive torques for achieving certain movements of the machine are calculated based on predefined feed acceleration. Appropriate drive stepping motors are chosen based on calculated drive torques. One of the basic conditions which machine must fulfill is that the displacement of the plasma torch tip must not be greater than 0, 02 mm. As the plasma cutting is a contactless technology, the cutting forces are negligible. Therefore, construction of the machine is loaded only with inertial forces caused by acceleration of certain machine parts. Mentioned inertial forces are calculated for the worst case of operating. Furthermore, displacement of the plasma torch tip is calculated based on obtained results for deformations of basic structural components of machine. According to the analysis, displacement of the plasma torch tip is less than 0, 02 mm and thus it is concluded that the machine meets the requirements. The machine is created on the basis of analysis and 3D model and it is concluded that even in the exploitation, the machine has fulfill required accuracy.

Paper presents main influencing variables on veldability special overview on weldability of quench and tempered steels. Investigations of sensitivity to cold cracks by Tekken method are performed and presented in the paper. Tekken method use into consideration influence of base and filler metal, influence of weld thermal cycle, preheating temperature and content of diffusion hydrogen. As final result of this paper, they were proposed welding parameters which are valid for cold cracks avoidance.

Hydraulic systems provide good dynamic behaviour and therefore are one of the main design concept for industrial applications, such as the example of drives for machine tools. The most important part of the hydraulic system is the pump. The main task of the pump is the converting mechanical energy from the prime mover into hydraulic energy, or the flow and pressure, with as high efficiency as possible. The paper shows the experimental determination of the actual flow rate of one type of the external gear pump, depending on the load condition. The analysis of test results shows the linear dependence of the actual flow rate of the pump and the discharge pressure. On the basis of the mathematical model, the volumetric efficiency values of the pump are obtained. They deviate from about 1 % of the experimentally determined values, which justifies the applied model. The presented model can be the basis for the simulation as in the example shown in this paper, while the experimental model can also be applied in exploitation conditions. Namely, the experimental model of the pump can be employed for diagnostic purposes and for the simulation of the hydraulic device.