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  • Advanced planning and scheduling in Jaksche TechnologyIgor Gruden, CADCAM Lab d.o.o.


    Heidrun Andre, Jaksche Kunststofftechnik GmbH
    Benjamin Hamzić, CADCAM Solutions d.o.o.

    No manufacturing environment can operate without a plan and the plans must be made at multiple 'levels' (Sales and Operations, Production planning, Production scheduling) considering different time frames.
    Planner is faced with difficult task: make an optimal manufacturing plan and production schedule, in order to achieve best performance in terms of maximizing assets utilization, shorten production lead times, synchronize flow of material, minimize stock and increase stability of plan. At the end of the day planner wants to have complete control over planning and customer service should be at high levels.
    In the paper we present some experience and data gained in the process of implementing the planning and scheduling solution in Jaksche Technology company in their plant in Bosnia and Herzegovina.
    For the successful implementation of Advanced Planning and Scheduling software (APS) it is preferred for a company to have a very good and well implemented ERP and MES system.
    Implementing the APS solution takes about four to six months depending on the size of company.
    During the implementation we made a digital copy of production with all the machines, operations, operators, and other constraints that can be found in production. Jaksche Technology wants to achieve the following benefits: delivery on time, management of human skills, reporting and better usage of molds (maintenance, availability) which is their biggest problem.
    Jaksche technology has Pantheon as ERP, Blender as MES and now ORTEMS as APS system which connects all the databases together. We present the testing phase, which lasted two months, where we confirmed that their manufacturing became more flexible, adaptable and responsive.
  • Bio-composites from recycled polypropylene and wastepaperSilvester Bolka, Fakulteta za tehnologijo polimerov


    Teja Pešl, Fakulteta za tehnologijo polimerov
    Rebeka Lorber, Fakulteta za tehnologijo polimerov
    Tamara Rozman, Fakulteta za tehnologijo polimerov
    Rajko Bobovnik, Fakulteta za tehnologijo polimerov
    Miroslav Huskić, Fakulteta za tehnologijo polimerov

    In this paper, we present the development of bio-composites with recycled polypropylene (rPP) matrix delivered by the company TAB-IPM d.o.o., wastepaper as a filler delivered by the company Papirnica Vevče Proizvodnja d.o.o., and maleic anhydride grafted polypropylene (PP-g-MA) compatibilizer.
    Compounding was performed on the twin-screw extruder. The addition of wastepaper was 5 wt.%, and 10 wt.%, the addition of PP-g-MA was 4 wt.%. For the characterization purposes, the test pieces were prepared by injection moulding according to ISO 527 (form 1BA), ISO 178, and ISO 179. Bending E modulus was higher with the addition of the wastepaper (for 15 % and 23 % at 5 wt.% and 10 wt.% of wastepaper respectively) and also bending strength was higher (for 7% and 10% at 5 wt.% and 10 wt.% of wastepaper respectively). The results of the tensile tests and DMA tests show the same tendency. The higher moduli and also higher strength indicate high compatibility of the bio-composites. With addition of 10 wt.% wastepaper, the thermal conductivity, the impact strength and degradation temperature were increased, while the melting and crystallization temperature remained the same.
    The authors would like to acknowledge the financial support received in the frame of the Slovenian smart specialization program (CEL.CYCLE - http://celkrog.si/?lang=en, grant number C3330-16-529004).
  • Collaborative and industrial robots – what do we really want, collaborativeness or speed of robots?Tim Tim VrbančičVrbančič, Inea RBT d.o.o.


    Jan Kramžar, Inea RBT d.o.o.

    Collaborativeness also means safety, while speed in case of robots means short cycles. Collaborative robots without any doubts deliver unique functionalities – beside higher safety, robot arm can be hand-guided, and programming of robot moves is simplified and intuitive, which enables higher flexibility of robot process. Industrial robots on other hand are faster, designed for fast cyclising, large production series and are bringing higher precision. Industrial robots with help of safety sensors can become also (limited) collaborative – in case of operator interference in working area, robot can slow down or stop, however highest possible collaborativeness (what is possible to achieve with collaborative robots) can not be achieved with industrial robots. Most of time standard industrial robot with collaborative equipment/functions will be fast, process will be productive and robot will work in collaborative mode only when needed. In case of collaborative robot applications questions can arise regarding other factors of robot application. Can sharp, hot and other dangerous workpieces be part of collaborative robot application? Risk level of collaborative process is hard to assess, however it is also needed to satisfy ISO safety standard which determines highest speed, power and force of robot movements and ergonomics of robot in application. In this article we will try to clarify mentioned problematics, beside that we will list possible use cases, where usage of collaborative robot really makes sense.
  • Controlled tigtening in today's industry - Industry 4.0Primož Žabjek, Žabjek d.o.o.


    In short presentation we will introduce news and trends in controlled tigtening systems.
  • Delivery of centralised applications and information to any device in manufacturing environmentPeter Skopec, ControlTech


    Jože Perko, ControlTech

    ThinManager is an advanced solution that ThinManager allows users to easily manage the configuration of end-user terminals and the delivery of all centralised applications and content to those terminals.

    ThinManager’s wizard-based configuration allows administrators to easily set up advanced functionality for end-user devices such as PCs, thin clients and mobile devices. ThinManager also makes it easy to customise the content delivered to the terminal based on who is logged in and what role they play in the production process.

    In the event of a client failure, the downtime is greatly reduced. This centralised solution raises the reliability of the system by replacing the client in just minutes, and a completely redundant configuration is possible.
  • DEVELOPMENT, MANUFACTURING, AND CLINICAL TESTING OF CUSTOM HIP IMPLANT FOR A PATIENT WITH LARGE ACETABULAR BONE DEFECTUrška Kostevšek, Fakulteta za strojništvo Univerze v Mariboru


    Igor Drstvenšek, Fakulteta za strojništvo Univerze v Mariboru
    Tomaž Brajlih, Fakulteta za strojništvo Univerze v Mariboru
    Matjaž Vogrin, Univerzitetni klinični center Maribor
    Andrej Moličnik, Univerzitetni klinični center Maribor

    Large bone defects in total hip arthoplasty are becoming more common. In cases of large defects and bone loss in acetabular defects, conventional or modular endoprostheses are commonly used. However, often these endoprostheses are not sufficient to establish hip stability.
    In this study custom-made medical devices have been developed and clinically tested. The presented method consists of dimensional operational planning, the manufacturing of custom-made medical devices, clinical trial and the post-operative analysis of implant’s position.
    With a developed and clinically tested method, the achievable precision was determined, and the operational technique simplified. Three-dimensional planning and operational procedure within the method was more transparent, more reliable and safer. The method did not only improve the operational technique, but also by using a custom-made implant, the stability of the hip was improved, the symmetry was assured, and the congenital anatomy was recovered.
  • DUST PARTICLES EMISSIONS AT STAINLESS STEEL WELDINGBorut Kosec, Univerza v Ljubljani, Naravoslovnotehniška fakulteta


    Nenad Petić, Univerza v Ljubljani, Naravoslovnotehnška fakulteta, Aškerčeva cesta 12, 1000 Ljubljana, Slovenija
    Milana Ilić Mićunović, Univerzitet u Novom Sadu, Fakultet tehničkih nauka, Trg D. Obradovića 6, 21000 Novi Sad, Srbija
    Mirza Imširović, Univerza v Ljubljani, Naravoslovnotehnška fakulteta, Aškerčeva cesta 12, 1000 Ljubljana, Slovenija
    Damjan Klobčar, Univerza v Ljubljani, Fakulteta za strojnitvo, Aškerčeva cesta 12, 1000 Ljubljana, Slovenia
    Igor Budak, Univerzitet u Novom Sadu, Fakultet tehničkih nauka, Trg D. Obradovića 6, 21000 Novi Sad, Srbija
    Zorana Tanasić, Univerza v Ljubljani, Fakulteta za strojnitvo, Aškerčeva cesta 12, 1000 Ljubljana, Slovenia
    Aleš Nagode, Univerza v Ljubljani, Naravoslovnotehnška fakulteta, Aškerčeva cesta 12, 1000 Ljubljana, Slovenija

    During welding procedures a lot of gases are emitted into the air, which can damage the health of the workers. Gases have different compositions and contain dust particles, which can provoke certain risks when inhaled by the workers. The degree of risk depends on the composition, concentration and time exposed to the harmful gases. Composition of gases depends on usage of different welding procedures, basic material and electrode.
    The idea of diploma work was to measure the emission of dust particles during manual arc welding of stainless steel with and without the use of ventilation device.
    Filtration of dust particles was conducted by EGO PLUS TT measuring instrument. Composition and geometry of dust particles were examined according to the standard ISO 13322 using using field emission scanning electron microscope Thermo Scientific Quattro S.
  • Go EConformal Mario Šinko, MARSI GROUP d.o.o.


    Matic Vogrin, MARSI GROUP d.o.o.

    How you can integrate conformal systems in to mold inserts to give your company complete control over injection molding processes and parameters together with light metal die casting.
    Introduction of our own brand.
  • IceJet technology: challenges and opportunities for Slovenian machine building industryJoško Valentinčič, Fakulteta za strojništvo, UL


    Marko Jerman, Fakulteta za strojništvo, UL
    Andrej Lebar, Fakulteta za strojništvo, UL
    Izidor Sabotin, Fakulteta za strojništvo, UL
    Suzana Vinetič, Fakulteta za strojništvo, UL
    Pavel Drešar, Fakulteta za strojništvo, UL

    The advantage of Abrasive water jet (AWJ) machining over related processes is that no heat-affected zone is created. The AWJ technology has been available in Slovenia since 1990, only 10 years after the first industrial use of this contour cutting process. The mineral abrasive, which is fed to a high-speed water jet with a diameter of less than one millimeter, reaches speeds of up to 700 m/s and allows practically any material to be cut. Despite the obvious advantages, the use of the process in the food and aerospace industries is unacceptable since the traces of mineral abrasive particles remain on the treated surface. Investigations into the material properties of ice have shown that heavily cooled ice grains have a similar hardness to softer mineral abrasives, so we are researching and developing a technology that uses ice grains instead of mineral abrasives. A cooled high-speed water jet delivers highly cooled ice grains to to the cutting front to cut hard materials. Recent research has confirmed the survival of ice beads under the extreme conditions of the cutting head. On the basis of our results and publications to date, we have aroused the interest of industry both in the EU and Asia that already shows the need for this technology and thus opens up new opportunities for the Slovenian machine buliding industry.
  • Improve Equipment Performance with smart automation and standardized equipment interfacesKlemen Lisec, Inden d.o.o.


    Dušan Božič, Inden d.o.o.
    Jochen Kinauer, camLine GmbH

    The ultimate objective of manufacturing will focus in the future to produce the highest quality of products, with as low cost as possible. Translated into requirements this means that throughput, equipment uptime and yield needs to be continuously increased in a manufacturing environment while improvements or next generations of products will be implemented in parallel. Automation is a key element to understand the relevant process behavior, monitoring and controlling the process windows, ensuring stable processes, achieving the necessary product quality at all times, guaranteeing error-free production and promptly detecting any anomalies.

    Collecting and evaluating all of the applicable data and controlling the equipment performance with a high order of complexity are the challenges of automation. The ability to do this reliable, predictable and flexible has a direct impact on factory performance and using standard equipment interfaces will reduce the integration cost and time.
  • Industry 4.0 Readiness Index for manufacturing companiesIztok Palčič, Univerza v Mariboru, Fakulteta za strojništvo


    Robert Ojsteršek, Univerza v Mariboru, Fakulteta za strojništvo
    Borut Buchmeister, Univerza v Mariboru, Fakulteta za strojništvo

    Laboratory for Production and Operations Management from Faculty of Mechanical Engineering from Maribor has been cooperating for 17 years within the largest European research from the field of manufacturing activities – European Manufacturing Survey. Project coordinator is the Fraunhofer Institute for Systems and Innovation Research – ISI from Germany. Project consists of 17 partners from among others Austria, Swiss, Spain, Croatia, Serbia, Denmark etc. Slovenia joined the project in 2003 with the first survey. After that, we have performed our survey in 2006, 2009, 2012/13, 2015/16 and 2018/19. The survey is very useful for Slovenian manufacturing companies as it enables comparisons to other countries. The aim of the survey is to present the results to companies and wider audience. This paper deals with the use of advanced manufacturing technologies in Slovenian manufacturing companies in the light of Industry 4.0. The main objective of the paper is to determine the adoption of specific advanced manufacturing technologies, namely digital factory technologies. At the same time, we present an Industry 4.0 Readiness Index and assess Industry 4.0 readiness of Slovenian manufacturing companies. The results are presented with the use of descriptive statistics. Results show that the use of specific advanced manufacturing technologies in Slovenian manufacturing companies is quite diverse and that Industry 4.0 readiness increases.
  • INFLUENCE OF SHIELDING GAS ON FUME FORMATION RATE IN GMAW WELDINGEdvard Bjelajac, Messer Slovenija d.o.o.


    Arc welding processes MIG/MAG with solid and flux cored wire, TIG and MMA produce fume gases, which negative influence on welder health. With welding process optimization, change of shielding gas and other optimization in production, we can influence on quantity of fume gases. With use of optimum shielding gas for specific use is possible to improve weldability, quality of welds and decrease costs of welding process.
  • Karakterizacija polimernih materialovMiroslav Huskić, Fakulteta za tehnologijo polimerov


    Silvester Bolka, Fakulteta za tehnologijo polimerov
    Blaž Nardin, Fakulteta za tehnologijo polimerov

    When purchasing polymeric materials, one usually relies on the properties listed in the technical datasheets. However, it is often noticed that the material or product does not behave as expected. There are several reasons for this: we could get material whose properties do not correspond to the written ones, use the wrong material for a particular application, use the wrong process parameters during processing, etc. Proper characterization of the material can tell us if there is a mistake on our side, or we can complain about the material. The lecture will briefly present various techniques for the characterization of polymers (infrared spectroscopy, nuclear magnetic resonance, thermal gravimetric analysis, dynamic mechanical analysis, etc.) and practical examples of their use in resolving complaints.
  • Mobile solutions to optimize and control industrial cleaning processesDaniel Frese, KRÜSS GmbH


    Robert Minch, KRÜSS GmbH

    In industries like automotive, aviation, medical or electronics, cleaning of components made from metals or polymers is an essential production step. Incomplete or improper cleaning will cause adhesive failure, coating defects and can result in tremendous costs. Ultrasonic baths, lasers or plasma torches are widely used to achieve proper cleaning, just to name a few of the manifold methods that are available. However, to control the result of such treatments, can be tricky, as critical contaminations are typically invisible to the eye and the question may arise: “How clean is my surface and is this clean enough?”. We will demonstrate, how mobile contact angle measurements offer a quick and easy solution to check the state of cleanliness, using ultrasonic bath cleaned steel plates as an exemplary sample. An optimum dwell time was defined and based on these findings an easy QC procedure could be established to control the cleaning process at line. We will explain the concept of surface free energy and how surface treatment like cleaning or plasma activation impacts this surface property. Other widespread measuring tools, in particular test inks or dyne pens, did not reflect the actual surface state, as will be demonstrated based on a comparative study performed on a wide variety of materials.
  • Polycarbonate recyclingBlaž Nardin, Fakulteta za tehnologijo polimerov


    Blaž Nardin, Fakulteta za tehnologijo polimerov

    In this paper the introduction of the recycling of an engineering thermoplastic material with short lifetime of the products for which multiple mechanical recycling is desirable will be presented. Commercially available grades are either in linear or branched form, so both qualities were tested and compared.
    The aim of the research was to characterize the thermal, mechanical and optical properties of the polycarbonate (PC) in linear and branched qualities depending on the number of processing operations. Degradation can also be avoided to a good extent with the right additives, so two different concentrations of chain extender were added. The processing was simulated by repeated extrusion. Test pieces were prepared by injection moulding after repeated multiple extrusions. It has been observed that individual properties are linearly dependent on the number of recycling runs (color tone), and some of the properties do not exhibit linear dependencies (tensile strength in branched PC). Properties depend to a large extent on the amount of chain extender added in the linear PC form, and in the branched PC form this dependence is more difficult to detect. For some linear and branched PC, some properties are inverse with respect to the number of recycling runs, so it is very important for a recycled PC the ratio between linear and branched quality. With proper up-cycling, it is possible to produce recycled PC with the right characteristics for a given product, if the properties of the recycled PC are known in advance.
  • Post-processing results of computer tomography with GOM inspect softwareTomaž Brajlih, Univerza v Mariboru/Fakulteta za strojništvo


    Paper present possibilities of using GOM inspect software for postprocessing medical 3D CAD models. Three-dimensional reconstruction of medical exams has become an essential part of modelling and manufacturing patient specific medical devices. In case of large skull defects, patient specific implant modelling and manufacturing has already been established world-wide. Modelling of such an implant is based on 3D CAD model of patient’s bone tissue that is acquired from computer tomography medical exam. Three-dimensional reconstruction of DICOM results in performed by dedicated medical imaging software by processing spatially oriented greyscale pictures of patient’s cross-sections. Bone tissue model is acquired by image segmentation based on selected range of grayscale values. Due to examination slice thickness and image pixel sizes there is a significant staircase effect on the acquired 3D model. Next step is to smooth the model surface and reduce the number of mesh triangles in order to obtain a useably 3D model for implant modelling. Paper present the functionality of GOM inspect software for such a process.
  • Robot welding cell for welding stainless-steel wine tanks.Aleš Kocjančič, Yaskawa Slovenija d.o.o.


    Hubert KOSLER, Yaskawa Slovenija d.o.o.
    Aljoša ZUPANC, Yaskawa Slovenija d.o.o.
    Damian ŠIRAJ, Yaskawa Ristro d.o.o.
    Erih ARKO, Yaskawa Ristro d.o.o.
    Igor PUGELJ, Yaskawa Ristro d.o.o.
    Tomaž, Denis, Jure JEROVŠEK, MEDVED, JANEŽIČ, Yaskawa Ristro d.o.o.
    Matej MERKAČ, Yaskawa Slovenija d.o.o.

    The robot welding cell is a stand-alone unit designed for welding standard stainless-steel wine tanks. The welding process is TIG without filler material. Welding method required development of a dedicated clamping device and position unit. Integrated vison system offers easy use of the robotic cell.
    The robotic welding cell allows welding different diameters of round seam and connection sleeve on tank surface. Robot cell is served by one operator. Product is clamped by automatic procedure. Robot program is generated automatically based on the scanned position of the round seam. No additional cleaning of welds after robotic welding.

  • Waste biomass as a reinforcement for thermoplastic elastomerSilvester Bolka, Fakulteta za tehnologijo polimerov


    Teja Pešl, Fakulteta za tehnologijo polimerov
    Rebeka Lorber, Fakulteta za tehnologijo polimerov
    Tamara Rozman, Fakulteta za tehnologijo polimerov
    Rajko Bobovnik, Fakulteta za tehnologijo polimerov
    Blaž Nardin, Fakulteta za tehnologijo polimerov

    The goal of the development of a thermoplastic elastomer bio-composite was to offer the market a flexible composite with as high bio-based components as possible. This was achieved by using polyethylene high density, which was synthesized from sugar cane and waste biomass as reinforcing additive.

    In this paper, we present a bio-composite with waste biomass and a thermoplastic elastomer matrix, which is designed for outdoor applications and will be first used to make prototypes of handles for hiking or walking or ski poles. The influence of different amount of waste biomass in the bio-composites and the influence of different quantity of the added PE-HD component were tested. In protoyping the influence of different Masterbatch additives on the colour change was also addressed and investigated. Prototypes were injection moulded at the company Tehnomat d.o.o, which is a world-renowned manufacturer of handles for hiking, walking and ski poles. The characterization of the properties was performed in the laboratories of the Faculty of Polymer Technology. Mechanical and thermal properties and dynamic mechanical properties were evaluated.
    The authors would like to acknowledge the financial support received in the frame of the Slovenian smart specialization program (CEL.CYCLE - http://celkrog.si/?lang=en, grant number C3330-16-529004).