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Ključni element kakovosti posameznikovega življenja je nedvomno ohranjanje ustreznega zdravstvenega stanja. V primeru potrebe po vzpostavitvi učinkovite farmakoterapije se zavedamo, da različne populacije bolnikov potrebujejo različne režime odmerjanja zdravil in da lahko individualizirane farmakoterapije povečajo tako uspešnost terapije kot tudi adherenco bolnikov. Zaradi tega se vedno bolj razvijajo napredni pristopi formuliranja, t.i. farmacevtskih oblik po meri, ki bi v prihodnosti izpolnjevale individualne potrebe bolnikov. Med te pristope spada tudi tehnologija nanašanja ZU na biokompatibilne podlage z metodo 2D tiskanja, kar za učinkovine z nizkimi odmerki in/ali ozkim terapevtskim oknom predstavlja možnost individualnega odmerjanja in prilagojene terapije. Zaradi potrebe po specifični ozki porazdelitvi velikosti delcev, ki bodo po redispergiranju v osnovnih medijih za kartuše izkazovali ustrezne lastnosti za uspešno 2D tiskanje, je za izdelavo tovrstnih delcev primerna metoda elektrostatskega razprševanja. Ta s spreminjanjem številnih formulacijskih in procesnih parametrov omogoča izdelavo mikrodelcev različnih lastnosti. Tako smo s pomočjo elektrostatskega razprševanja skušali izdelati delce z modelno učinkovino ustrezno majhnih velikosti, ki bi bili primerni za kasnejšo uporabo v kartušah za 2D tiskanje. V raziskovalnem delu smo z metodo elektrostatskega razprševanja kloroformovih raztopin polimera preučili proces izdelave in ovrednotili velikost ter morfologijo mikrodelcev samega polimera polikaprolaktona (PCL) ter nato preučili razprševanje zmesi simvastatina in PCL in zmesi simvastatina in kombinacij PCL z različno molekulsko maso. Na podlagi spreminjanja procesnih parametrov smo poskušali najti najbolj optimalno kombinacijo le-teh za izdelavo delcev ustrezne porazdelitve velikosti in oblike. Pri vseh raztopinah višje molekularnega polimera smo dobili sferične delce. Razlika v morfologiji se pokaže pri uporabi kombinacije polimerov, kjer nastanejo delci z večjim deležem morfoloških nepravilnosti. Pri elektrostatskem razprševanju raztopin polimera in učinkovine v razmerju 9 : 1 smo izdelali sferične mikrodelce z gladko površino. Pri teh raztopinah smo ovrednotili vpliv procesnih parametrov na velikost mikrodelcev. Najustreznejše delce, ki smo jih izdelali iz tega razmerja polimera in učinkovine pri optimiziranih procesnih parametrih, smo nato redispergirali v treh osnovnih medijih za kartuše. Mediji za kartuše so bili sestavljeni iz propilenglikola in vode v različnih volumskih razmerjih (10 : 90, 50 : 50 in 90 : 10). Izdelani delci so po redispergiranju tvorili skupke, zato bi bilo izdelanim delcem smiselno dodati hidrofilno oblogo. Metoda elektrostatskega razprševanja se je izkazala za učinkovito pri izdelavi ogrodnih mikrodelcev simvastatina in polikaprolaktona, vendar nastali delci niso primerni za uporabo v kartušah za 2D tiskanje. A key element in an individual's quality of life is undoubtedly maintaining an adequate state of health. In the case of the need to establish effective pharmacotherapy, we recognize that different patient populations require different dosing regimens and that individualized pharmacotherapies can increase both treatment success and patient adherence. For this reason, advanced formulation approaches are increasingly being developed, i.e. customized pharmaceutical forms to meet the individual needs of patients in the future. These approaches include the technology of applying active pharmaceutical ingredient (API) to biocompatible substrates using 2D printing method, which for active ingredients with low doses and/or narrow therapeutic window represent the possibility of individualized dosing and tailored therapy. Due to the need for a specific narrow particle size distribution, which after redispersion in the media for cartridges has the appropriate properties for successful 2D printing, the electrospraying method is suitable to produce such particles. By changing various formulation and process parameters, microparticles with different properties can be produced. Thus, we have attempted to use the electrospraying method to produce particles with a model drug in sufficiently small sizes suitable for subsequent use in cartridges for 2D printing. In the research work, we studied the production process using the method of electrostatic spraying of chloroform solutions of the polymer and evaluated the size and morphology of the microparticles of the polycaprolactone (PCL) polymer itself. We then investigated spraying of a mixture of simvastatin and PCL and a mixture of simvastatin and combinations of PCL with different molecular weights. By changing the process parameters, we tried to find the optimal combination of process parameters to produce particles with the appropriate size and shape distribution. Spherical particles were obtained in all solutions of the polymer with the higher molecular weight. The difference in morphology is evident when a combination of polymers is used, forming particles with a higher proportion of morphological irregularities. Spherical microparticles with smooth surface were prepared by electrospraying solutions of polymer and active ingredient in the ratio of 9 : 1. In these solutions, we evaluated the influence of process parameters on the size of microparticles. The most suitable particles that we produced from this ratio of polymer and active ingredient at the most optimal process parameters, were then redispersed in the three media for cartridges. The cartridge media consisted of propylene glycol and water in different volume ratios (10 : 90, 50 : 50 and 90 : 10). The produced particles formed aggregates after redispersion, so it would be useful to apply a hydrophilic coating to the manufactured particles. The electrospraying method proved effective in the preparation of simvastatin and polycaprolactone scaffold microparticles, but the resulting particles are not suitable for use in 2D print cartridges.

Diplomsko delo obravnava lasersko označevanje DMC-kode na avtomatnem jeklu 11SMnPb30, zaščitenem s cink-nikljevo prevleko. Ključni parametri pri laserskem označevanju so laserska moč, frekvenca označevanja, hitrost premikanja laserske glave, širina laserskega žarka in defokus. Namen diplomskega dela je bil ugotoviti vpliv posameznega parametra na kakovost označene DMC-kode. Do rezultatov smo prišli tako, da smo posameznemu parametru spreminjali vrednost in spremljali vpliv na označeno površino. Zajem dobljenih slik smo opravili z optičnim mikroskopom, vpliv na kakovost pa preverili z verifikatorjem. Iz dobljenih rezultatov smo ugotovili, da največji vpliv na kakovost DMC-kode dosežemo s spreminjanjem laserske moči, frekvence označevanja in hitrosti premikanja laserske glave. The bechelor`s thesis discusses with laser marking of DMC code on zinc – nickel plated 11SMnPb30 free cutting steel. The key parameters in laser marking are laser power, marking frequency, laser head speed, laser beam width and defocus. The aim of the thesis was to determine the influence of each parameter on the quality of the marked DMC code. To determine this, we varied the value of each parameter and monitored the effect on the marked area. The images obtained were captured using an optical microscope and the effect on quality was checked by using a verifier. From the results obtained, we found that the greatest impact on the quality of the DMC code is achieved by varying the laser power, the marking frequency and the laser head movement speed.

U ovom diplomskom radu ispitivan je utjecaj procesnih parametara prešanja na iskorištenje hladno prešanog konopljinovog ulja. Prešanje sjemenki konoplje provedeno je na kontinuiranoj pužnoj preši u laboratoriju. Tijekom proizvodnje ulja mijenjali su se procesni parametri: veličina otvora glave preše, temperatura glave preše te frekvencija elektromotora. Finalno hladno prešano ulje dobilo se nakon provedene sedimentacije i vakuum filtracije. U proizvedenom ulju određeni su osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, vlaga te udio netopljivih nečistoća. Na proizvedenom hladno prešanom ulju ispitan je i utjecaj dodatka antioksidanasa i sinergista na oksidacijsku stabilnost ulja Schaal Oven testom pri 63 °C. Od antioksidanasa korišteni su ekstrakt ružmarina, ekstrakt kadulje, ekstrakt zelenog čaja, mješavina tokoferola, kafeinska kiselina, a od sinergista askorbinska i limunska kiselina. Rezultati su pokazali da promjena procesnih parametara prešanja utječe na iskorištenje ulja, a dodaci antioksidanasa i sinergista doprinose stabilizaciji i održivosti ulja. In this thesis, the influence of process parameters on the use of cold-pressed hemp oil was investigated. The pressing of hemp seeds was carried out on a continuous screw press in the laboratory. During oil production, the process parameters changed: the size of the press head opening, the temperature of the press head and the frequency of the electric motor. The final cold-pressed oil was obtained after sedimentation and vacuum filtration. The basic quality parameters of cold-pressed oil are also determined in the oil: peroxide value, free fatty acids, moisture and the proportion of insoluble impurities. The influence of the addition of antioxidants and synergists on oxidizing oils was also tested on the produced cold-pressed oil using the oven stability test at 63 °C. Rosemary extract, sage, green tea extract, tocopherol mixture, caffeic acid are used as antioxidants, and ascorbic and citric acid are used as synergists. The results showed that the change in process parameters affects the utilization of the oil, and the addition of antioxidants and synergists contribute to the stabilization and sustainability of the oil.

Over the past few decades, additive manufacturing (AM) has become a reliable tool for prototyping and low-volume production. In recent years, the market share of such products has increased rapidly as these manufacturing concepts allow for greater part complexity compared to conventional manufacturing technologies. Furthermore, as recyclability and biocompatibility have become more important in material selection, biopolymers have also become widely used in AM. This article provides an overview of AM with advanced biopolymers in fields from medicine to food packaging. Various AM technologies are presented, focusing on the biopolymers used, selected part fabrication strategies, and influential parameters of the technologies presented. It should be emphasized that inkjet bioprinting, stereolithography, selective laser sintering, fused deposition modeling, extrusion-based bioprinting, and scaffold-free printing are the most commonly used AM technologies for the production of parts from advanced biopolymers. Achievable part complexity will be discussed with emphasis on manufacturable features, layer thickness, production accuracy, materials applied, and part strength in correlation with key AM technologies and their parameters crucial for producing representative examples, anatomical models, specialized medical instruments, medical implants, time-dependent prosthetic features, etc. Future trends of advanced biopolymers focused on establishing target-time-dependent part properties through 4D additive manufacturing are also discussed.

U ovom radu se ispituje sadržaj fenolnih jedinjenja i antioksidativna aktivnost kruničnih listića biljke Papaver rhoeas (poznata još kao bulka) da bi se utvrdio njen potencijal kao izvor prirodnih antioksidanata. U cilju dobijanja antioksidanata iz biljke Papaver rhoeas, krunični listići biljke ekstrahovani su metodom suksesivne ultrazvučne ekstrakcije (UAE) pri čemu je ispitivano kako procesni parametri utiču na kvalitet ekstrakcije i antioksidativnu aktivnost dobijenih ekstrakta. Ispitivani su procesni parametri: dužina trajanja ultrazvučne ekstrakcije (5 i 15 minuta), radna jačina ultrazučnog kupatila (96 i 240W) i količina upotrebljnog rastvarača (odnos osušenog biljnog materijala i rastvarača 1:10 i 1:25 w/v). U dobijenim ekstraktima je ispitivana ukupna količina fenola i flavonoida, kao i antioksidativna aktivnost. Najaktivniji ekstrakt je dalje analiziran metodom visoko-efikasne tečne hromatografije spregnute sa detektorom sa nizom dioda (HPLC-DAD) radi detaljnije kvalitativne i kvantitativne analize fenolnih jedinjenja. Dobijeni rezultati ukazuju da ispitivani procesni parametri nemaju značajan uticaj na sadržaj ukupnih fenola i flavonoida i antioksidativnu aktivnost u dobijenim ekstraktima, zbog čega se parametri UAE mogu birati na osnovu ekonomičnosti. U ekstraktima je pronađena ukupna količina fenola (77 – 86 mg GAE/g s.e.) i flavonoida (224 - 265 mg QE/g s.e.). Antioksidativna sposobnost ekstrakta je ispitana dvema metodama i izražena kao sposobnost redukcije gvožđa (FRAP) i kao sposobnost neutralizacije odnosno inhibicije 2,2-difenil-1-pikrilhidrazil (DPPH) radikala. Pronađena je antioksidativna aktivnost u vrednostima od 380 – 442 μmol Fe2+/g i preko 80% inhibicije svakog ekstrakta. Dobijeni rezultati HPLC-DAD analize ukazuju na veće prisustvo flavonoida u kruničnim listićima bulke pri čemu su od ispitivanih fenolnih jedinjenja rutin, epikatehin i daidzin prisutni u največim količinama (16,78 ± 0,34 mg/g, 5,70 ± 0,11 mg/g i 4,73 ± 0,10 mg/g, respektivno).

Liposomi so sodobni dostavni sistemi zdravilnih učinkovin, ki so bili razviti z namenom izboljšanja farmakokinetičnih lastnosti in s tem biološke uporabnosti učinkovin. Metoda injiciranja je ena izmed metod priprave liposomov s potencialom za prenos na masovno proizvodnjo v industrijskem merilu. Izhajajoč iz slednjega, je bil namen magistrske naloge raziskati vpliv procesnih parametrov na izdelavo liposomov njihovo velikost, porazdelitvijo velikosti ter zeta potencial pred in po membranskem ekstrudiranju, pri uporabi različnih organskih topil, ki v literaturi še niso dobro raziskana, za izbrane pomožne snovi. Topila smo izbirali glede na topnost liposomskih komponent. Testirali smo naslednje procesne parametre: hitrost dodajanja organske faze v vodno fazo, volumen demineralizirane vode, hitrost mešanja ob injiciranju in temperatura med pripravo liposomov. Pri zasnovi poskusov in analizi podatkov smo upoštevali metodo načrtovanja eksperimentov. Vzorce smo ovrednotili z merjenjem velikosti, porazdelitve velikosti in zeta potenciala. Glede na topnost pomožnih snovi smo se odločili, da bomo načrtovali poskuse pri treh topilih: metanolu, zmesi metanola in etil acetata v volumskem razmerju 1:1 ter izopropanolu. S pomočjo statistične analize smo za izdelane liposome ugotovili, da modela vpliva procesnih parametrov na velikost liposomov pri vzorcih z metanolom in zmesi metanola in etil acetata nismo uspeli določiti. Pri vzorcih z izopropanolom smo dobili model s 55 % napovedno močjo, kjer ima na velikost liposomov vpliv temperatura priprave vzorca. Ker membransko ekstrudiranje omogoča poenotenje velikosti liposomov, se vpliv procesnih parametrov zabriše in modela ni mogoče postaviti. Modela za določitev zeta potenciala liposomov pred in po ekstruziji tudi ni mogoče postaviti, saj je vrednost zeta potenciala odvisna predvsem od komponent, ki sestavljajo liposome. Glede na procesne parametre se je spreminjal zaostanek topila v vzorcih, ki je najnižji pri hitrem mešanju, visoki temperaturi segrevanja, velikem volumnu vodne faze (velja le za metanol). Glede na eksperimentalne rezultate, smo potrdili tudi ponovljivost temperature segrevanja in hitrost dodajanja raztopine lipidov v organski fazi. Liposomes are modern delivery systems for active substances that have been developed to improve the pharmacokinetic properties and thus the bioavailability of active substances. The injection method is one of the methods for the preparation of liposomes with the potential to be transferred to the mass production on an industrial scale. Starting from the latter, the aim of this thesis was to investigate the influence of process parameters on the production of liposomes their size, size distribution and zeta potential before and after membrane extrusion, using different organic solvents, which are not yet well studied in the literature, for selected excipients. The solvents were chosen according to the solubility of the liposomal components. The following process parameters were tested: organic phase addition rate, volume of demineralised water, stirring speed at injection and temperature during liposome preparation. The experimental design and data analysis followed the design of experiments method. Given the solubility of the excipients, we decided to design the experiments using three solvents: methanol, a mixture of methanol and ethyl acetate (1:1 (V/V)), and isopropanol. Statistical analysis revealed that we were unable to determine a model for the effect of process parameters on liposome size for methanol and mixture of methanol and ethyl acetate samples. For isopropanol samples, we obtained a model with 55 % predictability, where the liposome size is influenced by the sample preparation temperature. Since membrane extrusion makes the liposome size uniform, the influence of process parameters is blurred and the model cannot be established. A model for the estimation of the zeta potential of liposomes before and after extrusion is also not possible as the zeta potential value depends on the components of the liposomes. Depending on the process parameters, the solvent residual in the samples varied, being lowest with rapid mixing, high heating temperature, large volume of aqueous phase (only for methanol). According to the experimental results, we also confirmed the reproducibility of the temperature during liposome preparation and the organic phase addition rate.

Sheme prehrambeno-tehnoloških procesa su iznimno važni dijelovi tehničke dokumentacije industrijskih postrojenja. Sheme su nužne pri planiranju i izradi tehničke dokumentacije strojarskog dijela postrojenja, pri upravljanju i gradnji postrojenja te za vođenje tehnološkog procesa, tehničke preglede, rad i održavanje postrojenja. Pri izradi shema prehrambenotehnoloških procesa koristimo se normiranim simbolima koji prikazuju pojedine uređaje ili procesne tokove. Kada se procesna shema u potpunosti definira može se provesti simulacija procesa koja nam daje relevantne informacije o funkcioniranju procesa i prije njegove konačne izvedbe. Simulacijski modeli industrijskog procesa omogućavaju definiranje niza procesno važnih procesnih parametara kao što su protok, sastav, temperatura, tlak i sl. Poznajući navedene procesne parametre možemo utvrditi potrebe za sirovinama, utrošenom energijom, kapacitetom procesne opreme i dr. Food processes diagrams are the most essential parts of the technical documentation of process plants. They are necessary for the planning and preparation of the technical documentation of the mechanical part of the plant, in the management and construction of the plant, and for managing the technological process, technical inspections, operation and maintenance of the plant. When designing schemes, we use symbols that show individual flows and the entire process plant and follow the rules for creating projects of foodtechnological processes. When the process scheme is fully defined, a simulation of the process can be carried out, which will provide information about the functioning of the process even before its final execution. This process simulation model allows the prediction of a number of process-important parameters such as flow, composition, temperature, pressure, etc. According to these parameters, we can determine the needs for raw materials, energy consumed, process equipment capacity, etc.

U ovom radu istraživan je utjecaj procesnih parametara prešanja sjemenki crnog kima na prinos hladno prešanog ulja te njegovu kvalitetu. Prešanje sjemenki crnog kima provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem su dobivena tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjani su procesni parametri: frekvencija elektromotora, temperatura grijača glave preše i nastavak za izlaz pogače. Nakon prešanja provedena je sedimentacija (prirodno taloženje) proizvedenog sirovog ulja te vakuum filtracija kako bi se uklonile krute čestice. Primjenom standardnih metoda određeni su parametri kvalitete hladno prešanog ulja crnog kima: slobodne masne kiseline, peroksidni broj, udio netopljivih nečistoća i udio vlage. Primjenom plinske kromatografije određen je sastav masnih kiselina u ulju. Dobiveni rezultati istraživanja pokazuju da je prešanje crnog kima primjenom nastavka za izlaz pogače veličine 5 mm, temperature grijača glave preše 110 °C i frekvencije elektromotora 20 Hz proizvedena najveća količina sirovog i hladno prešanog ulja crnog kima. U sastavu masnih kiselina ulja crnog kima dominiraju linolna i oleinska masna kiselina., This thesis, discusses the influence and quality of process parameters of pressing black cumin seeds on the yield of cold pressed oil. Pressing black cumin seeds was carried out on laboratory screw press for the production of cold pressed vegetable oils. Three products were obtained by pressing: crude oil, sludge oil and cake. During pressing, the process parameters were changed: the frequency of the electric motor, the temperature of the heater of the press head and the extension for the outlet of the cake. After pressing, sedimentation (natural precipitation) of the produced crude oil and vacuum filtration were performed to remove solid particles. Using standard methods, the quality of parameters of cold-pressed black cumin oil were determined: free fatty acids, peroxide value, insoluble impurities content and moisture content. The composition of fatty acids in oil was determined using gas chromatography. The obtained research results show that the pressing black cumin using a 5 mm cake outlet extension, a press heater head temperature of 110 ° C and an electric motor frequency of 20 Hz produced the largest amount of crude and cold-pressed black cumin oil. In the composition of fatty acids black cumin oil is dominated by linoleic and oleic fatty acids.

Nepogrešljiva prisotnost kovinskih materialov v medicinskih aplikacijah je z najnovejšimi izzivi in trendi prehoda iz stalnih na začasne implantante bila razširjena tudi na raziskovanje biorazgradljivih kovinskih materialov. Glede na pomanjkljivosti prepočasne razgradnje zlitin na osnovi Fe, se dodatek Mn ter posledično zlitine iz sistema Fe-Mn obravnavajo kot ene najbolj perspektivnih za izdelavo in kasnejšo uporabo v želenih aplikacijah za medicinske namene. Pri ustvarjanju in razvoju novih zlitin in izdelkov iz navedenega binarnega sistema, ki bi izkazovali za telo neškodljivo in povečano stopnjo razgradljivosti, smo glede na ustvarjalne prednosti dodajalnih tehnologij izbrali selektivno lasersko taljenje. Z raziskavami smo v prvi vrsti dokazali razlike med uporabo mehansko mešanih elementarnih kovinskih prahov in predhodno izdelanimi zlitinskimi kovinskimi prahovi. Hitrost napredovanja korozije kot tudi raztapljanje izdelkov iz primerjanih kovinskih prahov izdelanih s selektivnim laserskim taljenjem v različnih medijih lahko ocenimo kot povsem primerljivo. Z omogočenim načinom spreminjanja obratovalnih parametrov (moč laserja in hitrost vrstičenja) in obsežno karakterizacijo materiala smo izdelali procesna okna, ki so nam služile za ugotavljanje vpliva in optimizacijo parametrov, kar je vodilo v izbiro najugodnejših obratovalnih parametrov za povečanje reakcijske površine in posledičnega hitrejšega napredovanja korozije. Iz potrebe po prekrivanju premera laserskega snopa in medlaserske razdalje smo izpeljali novo enačbo za izračun gostote vnesene energije. Za podrobno analizo in ugotovitev vpliva procesnih parametrov smo primerjali tudi vzorce izdelane z enako vneseno gostoto energije vendar uporabljenimi različnimi vrednostmi moči laserja in hitrosti vrstičenja. Kljub opaženemu splošnemu upočasnjevanju hitrosti napredovanja korozije ob dodatku Ag nam je s Fe-Mn-Ag zlitino in s skoraj polovično vrednostjo ustvarjene poroznosti uspelo izdelati material s hitrostjo korozije kar 1775,22 µm/leto. With the current trends to make a transition from permanent to temporary medical implants, the indispensable presence of metallic materials in medicinal applications has been extended to the research of biodegradable metallic materials. Taking the disadvantages of slow decomposition of Fe-based alloys into account, the addition of Mn and consequently alloys from the Fe-Mn system is considered one of the most promising for manufacturing and subsequent use in applications for medical purposes. In the creation and development of new alloys and products from the above binary system, which would show an increased degree of degradability, we have chosen a selective laser melting due to the creative advantages of additive manufacturing. Through our research, we firstly demonstrated the differences between the use of mechanically mixed elemental metal powders and prefabricated alloy metal powders systematically. The rate of corrosion progression as well as the dissolution of products from the compared metal powders made by selective laser melting in different media can be assessed as entirely comparable. With the ability of modifying the operating parameters (laser power and scanning speed), we created process maps at different levels of material characterization, which served us to determine the impact and optimize the parameters. It all led to the selection of the most favorable operating parameters to increase the reaction surface and consequently to a faster progress in corrosion. From the need to overlap the laser diameter and the hatch distance, we have derived a new equation to calculate the input energy density. For a more detailed analysis, and to determine the impact of process parameters, we have also compared the samples manufactured with the same input energy density but using different laser power and scanning speed combinations. Despite the general inhibition of the corrosion rate with the addition of Ag, we have managed to produce a material with as much as 1775.22 μm /year with FeMnAg alloy and almost half the value of the generated porosity.

U ovom radu istraživan je utjecaj procesnih parametara prešanja sjemenki crnog kima na prinos hladno prešanog ulja te njegovu kvalitetu. Prešanje sjemenki crnog kima provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem su dobivena tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjani su procesni parametri: frekvencija elektromotora, temperatura grijača glave preše i nastavak za izlaz pogače. Nakon prešanja provedena je sedimentacija (prirodno taloženje) proizvedenog sirovog ulja te vakuum filtracija kako bi se uklonile krute čestice. Primjenom standardnih metoda određeni su parametri kvalitete hladno prešanog ulja crnog kima: slobodne masne kiseline, peroksidni broj, udio netopljivih nečistoća i udio vlage. Primjenom plinske kromatografije određen je sastav masnih kiselina u ulju. Dobiveni rezultati istraživanja pokazuju da je prešanje crnog kima primjenom nastavka za izlaz pogače veličine 5 mm, temperature grijača glave preše 110 °C i frekvencije elektromotora 20 Hz proizvedena najveća količina sirovog i hladno prešanog ulja crnog kima. U sastavu masnih kiselina ulja crnog kima dominiraju linolna i oleinska masna kiselina. This thesis, discusses the influence and quality of process parameters of pressing black cumin seeds on the yield of cold pressed oil. Pressing black cumin seeds was carried out on laboratory screw press for the production of cold pressed vegetable oils. Three products were obtained by pressing: crude oil, sludge oil and cake. During pressing, the process parameters were changed: the frequency of the electric motor, the temperature of the heater of the press head and the extension for the outlet of the cake. After pressing, sedimentation (natural precipitation) of the produced crude oil and vacuum filtration were performed to remove solid particles. Using standard methods, the quality of parameters of cold-pressed black cumin oil were determined: free fatty acids, peroxide value, insoluble impurities content and moisture content. The composition of fatty acids in oil was determined using gas chromatography. The obtained research results show that the pressing black cumin using a 5 mm cake outlet extension, a press heater head temperature of 110 ° C and an electric motor frequency of 20 Hz produced the largest amount of crude and cold-pressed black cumin oil. In the composition of fatty acids black cumin oil is dominated by linoleic and oleic fatty acids.

Buča (Cucurbita pepo L.) je jednogodišnja biljka koja potječe iz Amerike, a sastoji se od mesnatog dijela ploda i koštice. Koštica može biti s ljuskom i bez ljuske. U ovom radu istraživan je utjecaj vrste pužnice i procesnih parametara na iskorištenje bučinog ulja. Proizvedeno je hladno prešano bučino ulje na kontinuiranoj laboratorijskoj pužnoj preši. Procesni parametri koji su se mijenjali prilikom prešanja su: frekvencija elektromotora, temperatura grijača glave preše i nastavak za izlaz pogače. Korištena su tri tipa pužnice s različitom dubinom navoja. Ispitani su osnovni parametri kvalitete ulja: slobodne masne kiseline, peroksidni broja, udio vode i udio netopljivih nečistoća. Analitički je određen udio ulja u bučinim košticama i pogači kako bi se odredila efikasnost proizvodnje ulja. Prešanjem bučine koštice kod veće temperature glave preše, manje frekvencije elektromotora i manjeg nastavka za izlaz pogače proizvedena je veća količina ulja. Primjenom pužnice dubine navoja 5 mm dobivena je veća količina ulja u odnosu na 8 mm i 10 mm. Pumpkin (Cucurbita pepo L.) is an annual plant that originate from America and it is made of pulpy part of fruit and pits. A pit can be with a husk or without one. The aim of this research was to analyze the influence of screw press type and process parameters on the utilisation of pumpkin seed oil. It was produced cold pressed pumpkin seed oil on continuous laboratory screw press. The process parameters, which were changed during the pressing process, are: the frequency of electric motor, temperature of the press heating head and nozzle size. There were used three screw press types with different thread depth. There were questioned the basic quality oil parameters such as free faty acid, peroxide value, water content and proportion of insoluble impurities. Oil extraction by Soxhlet method determined the proportion of oil in pumpkin seeds and cake so that it could be defined oil production efficiency. Analytically it was determined content of oil in pumpkin pits and nozzle so it could be determined oil production efficiency. With pressing pumpkin pit at higher press head temperatures, less frequency of electric motor and smaller nozzle size it was produced a larger amount of oil. Using screw press with thread depth of 5 millimeters it was gained a larger amount of oil in comparsion with 8 millimeters and 10 millimeters.

V sklopu zaključne naloge smo raziskovali vpliv procesnih parametrov pri laserskem graviranju titanove zlitine Ti-6Al-4V. Raziskovali smo vpliv hitrosti graviranja, frekvence in električnega toka laserskega vira. Najprej smo v programski opremi definirali geometrijo površine vzorca in geometrijo osmih vzporednih linij, ki smo jih gravirali. V naslednjem koraku smo definirali procesne parametre laserskega graviranja. Vsakemu izmed treh vzorcev smo spreminjali samo določen parameter, ostali pa so bili konstantni. Po izvedenem laserskem graviranju smo vzorce opazovali z digitalnim optičnim mikroskopom in raziskovali vpliv laserskega graviranja na spremembe na površini gravure. Ugotovili smo, da procesni parametri močno vplivajo na videz in geometrijo graviranega vzorca na titanovi zlitini. S povečevanjem hitrosti graviranja se povečuje razdalja med kraterji, ki jih ustvari laserski žarek. Ugotovili smo tudi, da se s povečevanjem frekvence pulzov zmanjšuje razdalja med kraterji, kot tudi njihov premer in hrapavost površine. Pri povečevanju procesnega parametra električnega toka se je premer kraterjev povečeval, razdalja med njimi pa zmanjševala. As part of the final bachelor thesis, we investigated the influence of process parameters in laser engraving of titanium alloy Ti-6Al-4V. We investigated the influence of engraving speed, frequency and electric current of the laser source. With the help of applicable software we first defined the surface geometry of the sample and the geometry of the eight parallel lines. Next, process parameters of laser engraving were defined. We only changed a certain parameter for each of the three samples, and the others were constant. After the laser engraving was carried out, the samples were observed with a digital optical microscope and the influence of laser engraving on the changes on the engraving surface was investigated. We found that the process parameters strongly influence the appearance and geometry of the engraved pattern on the titanium alloy. As the engraving speed increased, the distance between the craters created by the laser beam increased too. We also found that as the pulse frequency increases, the distance between the craters decreases, as does their diameter and surface roughness. As the process parameter of the electric current increased, the diameter of the craters increased and the distance between them decreased.

Zaradi starajočega prebivalstva in soobolevnosti se mora farmacevtska industrija vse bolj prilagajati in razvijati nove farmacevtske izdelke, tudi kombinacijske. Največ peroralnih zdravil je v obliki tablet, med katerimi prevladujejo filmsko obložene tablete. Pri filmskem oblaganju na tabletno jedro nanesemo filmsko oblogo, ki ima lahko vpliv na funkcionalnost končnega izdelka, lahko pa je nanešena zgolj z estetskega vidika. Ne glede na namen filmske obloge, moramo z vidika zagotavljanja kakovosti med oblaganjem zagotoviti enakomeren nanos obloge, saj je že enakomeren videz obloženih tablet eden izmed pomembnih atributov kakovosti filmsko obloženih tablet. V primeru, da je v oblogo tablete vključena učinkovina, pa moramo tudi za učinkovino v oblogi doseči zahtevo enakomernosti enoodmernih enot. S tega vidika je pomembno, da uporabljamo optimiziran proces oblaganja tabletnih jeder. Da bi se izognili nepričakovanim napakam pri izdelavi serij obloženih tablet in nedoseganju zahtevane kakovosti serij, moramo skrbno proučiti lastnosti procesa oblaganja tablet. Neustrezno načrtovanje procesa filmskega oblaganja lahko povzroči visoko variabilnost količine obloge med tabletami končnega izdelka. V izogib visoki variabilnosti količine obloge je potrebno ovrednotiti učinkovitost procesa oblaganja, določiti kritične procesne parametre ter razumeti njihov vpliv na kakovost obložene tablete. Namen magistrske naloge je ovrednotiti učinkovitost pilotnega oblagalnika tablet z vidika enakomernosti količine obloge med tabletami. Na podlagi taktično izbranih vrednosti procesnih spremenljivk procesa oblaganja in rigoroznega vrednotenja enakomernosti vsebnosti tablet smo postavili napovedna modela odvisnosti RSD količine obloge od kritične spremenljivke procesa oblaganja, t.j. od celokupnega števila obratov bobna. Izkazalo se je, da je vrednoten pilotni oblagalnik tablet učinkovit pri doseganju želene stopnje enakomernosti vsebnosti oz. količine obloge med tabletami. S pomočjo postavljenega modela za posamezno polnitev bobna lahko napovemo, kakšni so lahko pričakovani realno najboljši rezultati enakomernosti obloge pri izbranih pogojih oblaganja, upoštevaje tudi okvirje formulacije in omejitve procesne opreme, npr. najmanjši in največji pretok disperzije, ki lahko napaja šobo za razprševanje. Z izvedbo načrtovanega dela smo pokazali uporabnost eksperimentalnih napovednih modelov variabilnosti količine obloge pri vrednotenju učinkovitosti pilotnega oblagalnika tablet. Due to an ageing population and co-morbidity the pharmaceutical industry needs to constantly adapt and develop new pharmaceutical products, including fixed-dose combination products. Most of the oral medications are in a form of a tablet, with film-coated tablets being the most common ones. During the tablet film coating we apply a thin polymer coat to the tablet core, which can have an impact on the functionality of the final product, or it can be applied for aesthetic reason. Either way, we must ensure an even application of the coating due to the quality assurance, as the even appearance of coated tablets is one of the important attributes of the quality of film-coated tablets. If there is an active ingredient included in the tablet coating, the requirement of uniformity of dosage units must also be met for the active substance in the coating. From this point of view, it is important to use an optimized tablet core coating process. To avoid possible mistakes when producing batches of film-coated tablets and nonachievement of the required batch quality, we need to carefully study the properties of the tablet coating process. Improper planning of the film coating process can result in high variability in the amount of coating between tablets of the final product. In order to avoid high variability of coating amount, it is necessary to evaluate the efficiency of the coating process, determine critical process parameters, and understand their impact on the quality of the coated tablet. The purpose of the master's thesis is to evaluate the effectiveness of the pilot scale tablet pan coater in terms of uniformity of the amount of coating between tablets. Based on tactically selected values of process variables of the coating process and rigorous evaluation of the uniformity of tablet content, we set up predictive models of the dependence of the amount of coating RSD on the critical variable of the coating process, i.e. of the total number of drum revolutions. It turned out that the evaluated pilot version of the tablet coater is effective in achieving the desired degree of uniformity of content or the amount of coating between the tablets. With the help of the set model for individual drum filling, we can predict what can be expected realistically in terms of the best results of uniformity of the coating under selected coating conditions, also taking into account the formulation design and limitations of process equipment, e.g. the minimum and maximum dispersion flow that can supply the spray nozzle. By performing the experimental work, we demonstrated the applicability of the experimental predictive models of the coating amount variability in evaluating the performance of the pilot scale tablet coater.

V diplomski nalogi je prikazana primerjava laserskega razreza kovinskih in nekovinskih materialov. Glavni razlog je širša uporaba laserja v industriji in s tem rezanja več različnih materialov na enakem laserskem sistemu. Eksperiment smo izvedli na vzorcih iz najbolj pogosto uporabljenih kovinskih in nekovinskih materialov. Kakovost reza smo opravljali z vizualno analizo in na vsakem vzorcu izmerili hrapavost. Ugotovili smo, da na kvaliteto reza vpliva pet ključnih parametrov, ki so med seboj odvisni. Ob pregledovanju kvalitete reza smo ugotovili, da se parametri popolnoma razlikujejo, kakor tudi kakovost in spremembe na materialu. S pridobljenimi rezultati smo podali okvirne smernice primerjave in razumevanje laserskega rezanja kovin ter nekovin. The thesis provides a comparison of laser cutting of metallic and non-metallic materials. The main reason is a broader use of lasers in the industry and thus cutting of different materials with the same laser system. The experiment on samples of the most commonly used metallic and non-metallic materials were performed. The cut quality with a visual analysis and measuring the roughness on each sample was done. It was found that the cutting quality is affected by five interdependent parameters. During the cutting quality assessment, it was found that the parameters are completely different, as well as the quality and changes on the material. With the obtained results, a framework guidelines for comparing and understanding the laser cutting of metals and non-metals was provided.

Vsem proizvodnim procesom je skupno to, da vključujejo različne procesne parametre, ki pomembno vplivajo na končen rezultat postopka izdelave produkta. S procesnimi parametri izdelku izboljšamo lastnosti, podaljšamo dobo trajanja in povečamo funkcionalnost. Po drugi strani pa nepravilno izbrani procesni parametri lahko privedejo do precejšnjih težav, tako pri izdelku samem, kakor v smislu proizvodne učinkovitosti. V primeru drsnih obročev, elektro-mehanskih elementov, ki zagotavljajo učinkovit prenos električne energije ali drugih signalov iz stacionarnega na rotirajoči se del sistema, glavni problem pri izdelavi s postopkom injekcijskega brizganja termo plastnega polimera predstavlja prisotnost zračnih rež med posameznimi elementi zabrizganega drsnega obroča. Predstavljena magistrska naloga se tako osredotoča na opis procesa injekcijskega brizganja drsnih obročev ter s tem povezane problematike pojavljanja zračne reže. V aplikativnem delu je predstavljena analiza napak, korektivni ukrepi za njihovo odpravo ter uspešnosti uvajanja posameznih korektivnih ukrepov pri zmanjšanju zračne reže. Na podlagi eksperimentalno podprte večfazne metodološke analize preizkusnih serij je bilo ugotovljeno, da ima največji doprinos k izboljšanju obrizgavanja elementov in zmanjšanju pojava zračne reže predgretje elementov. Predgretje pa je potrebno kombinirati tudi z ustrezno prilagojenimi parametri procesa brizganja, ki vključujejo ustrezno visoko temperaturo taline, dovolj visok nadtlak in časovno usklajenost delovanja nadtlaka. Every production process contains a set of parameters, which have a significant role in the process outcome. By changing the parameters we can either greatly improve product’s properties, increase product lifetime or improve its functionality, or on the other hand, we can cause product nonconformities or decrease process efficiency. Slip ring, an electro-mechanical device, used to transfer electrical energy or signals from a stationary to a rotating part of the system, can be produced using an injection molding process, where electrical terminals are over molded with polymer material. In overmolding process, one of the major defects caused after production, is the delamination of different materials in the product. Issues concerning such phenomenon are described in this master’s thesis. The experimental part of the thesis contains defect analysis corrective measure for process improvement and describes efficiency of different process parameter changes in order to improve the end product. Based on experimentally based analysis, it was determined that preheating the inserts before overmolding has the greatest effect in preventing the delamination of materials. Preheating has the greatest effect, if combined with adequately adjusted injection molding parameters, such as sufficient melt temperature and correct combination of holding pressure value and its duration.

V okviru zaključne naloge smo pregledali teoretične osnove injekcijskega brizganja na podlagi katerih smo optimizirali proces injekcijskega brizganja geometrijsko enostavnega stojala za telefon z zatičem za sestavljanje iz poliamida 6. Z optimizacijo smo želeli izboljšati ter skrajšati proces injekcijskega brizganja z ozirom na funkcionalnost izdelka. Analizirali smo spreminjanje geometrije tečaja ter dolžine izdelka ob različnih procesnih parametrih ter potrebne sile za sestavljanje geometrijskega elementa. Eksperimente smo zasnovali s pomočjo metode načrtovanja eksperimentov ter optimizirali z uporabo Taguchijevih ortogonalnih matrik. In the master's thesis, we reviewed the theoretical foundations of injection molding. On that basis we optimized the injection molding process of a geometrically simple mobile phone stand with a hinge from polyamide 6. With optimization, we wanted to improve and shorten the injection molding process in regard to the functionality of the product. We analyzed changes in geometry of the hinge and part length at different process parameters and forces required to assemble geometric elements on our product. The experiments were performed in accordance to method called Design of experiments and optimized using Taguchi optimization technique.

Magistrska naloga zajema optimizacijo procesa injekcijskega brizganja polimerov izbranega izdelka iz poliamida VESTAMID L1930. Cilj optimizacije je bil določiti vpliv petih procesnih parametrov na dimenzijske lastnosti izdelka in skrajšanje časa cikla ob doseganju dimenzijskih toleranc. Predstavljene so teoretične osnove procesa injekcijskega brizganja polimerov, polimerih materialov in industrijskega eksperimentiranja. Dodaten poudarek je bil posvečen določitvi sposobnosti merilnega sistema. Določili smo sposobnost 3D-skenerja za merjenje karakteristik na izbranem izdelku. Optimizacija je bila izvedena po metodi načrtovanja eksperimentov z uporabo načrta s centralno zasnovo. Rezultate smo analizirali po metodi ANOVA. Določili smo optimalno nastavitev izbranih procesnih parametrov in ustreznost rezultatov preverili s potrditvenim eksperimentom. In this Master´s thesis, we performed the optimization of injection molding process of a selected polyamide product. The aim of the optimization was to determine the effects of five processs parameters on the dimensional properties of the product and to shorten the cycle time while achieving dimensional tolerances. The theoretical foundations of the processs of injection molding of polymers, polymer materials and industrial experimentaion are presented. Additional emphasis is placed on determining the capability of the Measurement System. Optimization was performed using the Design of Experiments method. The results were analyzed using the ANOVA method. We determined the optimal settings of the selected process parameters and checked the adequacy of the results with an Confirmatory Experiment.

Liposomi so sferični lipidni vezikli, ki zaradi sposobnosti vgradnje tako hidro- kot tudi lipofilnih učinkovin in tarčne dostave v farmaciji pridobivajo na svoji veljavi kot obetavni nanodostavni sistemi. Eden večjih izzivov je priprava liposomov v industrijskem merilu, kjer sušenje z razprševanjem predstavlja izreden potencial. Izhajajoč iz slednjega, je bil cilj magistrske naloge ovrednotiti vpliv različnih topil in parametrov sušenja z razprševanjem na izdelavo liposomov s predhodno določeno sestavo, s čimer bi pridobili pomembne podatke o možnosti prenosa metode izdelave na proizvodno raven. Na podlagi literature in eksperimentov smo poiskali primerno topilo za raztapljanje fosfolipidov (distearoilfosfatidilholin (DSPC), natrijeva sol distearoilfosfatidilglicerol (DSPG-Na)) in holesterola. Liposome smo izdelali tako, da smo raztopino pomožnih snovi sušili z razprševanjem pri različnih parametrih (hitrost razprševanja, hitrost in temperatura vstopnega zraka). Vmesni produkt smo nato rehidrirali z vodnim medijem ter nastale liposome ekstrudirali skozi polikarbonatno membrano. Na vmesnem produktu smo izvedli termično analizo, liposomom pa smo izmerili hidrodinamski premer, polidisperzni indeks in zeta potencial. Pri eksperimentalnem delu in analizi podatkov smo upoštevali princip načrtovanja eksperimentov, ki nam omogoča, da na majhnem številu eksperimentov dobimo maksimalno količino informacij za ovrednotenje procesa in končnega produkta. Glede na topnost pomožnih snovi in ICH smernic smo za pripravo disperzije izbrali dve topili: mešanico diklorometana in metanola v volumskem razmerju 1:1 in metanol. Proces raztapljanja DSPG-Na v topilih pa smo pospešili s segrevanjem disperzije na 40 °C. Z analizo nastalih liposomov smo ugotovili, da sta nanje imela vpliv le dva parametra sušenja z razprševanjem. Pri nižji hitrosti pretoka zraka dobimo večji izkoristek procesa, če zvišamo temperaturo vstopnega zraka po redispergiranju suhega produkta, pa dobimo manjše liposome. Premer začetnih liposomov se je s približno 800 nm po ekstruziji zmanjšal na 150 nm, medtem ko je bil zeta potencial v obeh primerih praktično enak. Z metodo termične analize vzorcev smo dokazali tudi odsotnost zaostanka topil v suhem produktu. Ključna ugotovitev magistrskega dela je, da se z ekstruzijo liposomov vplivi parametrov sušenja z razprševanjem na velikost in porazdelitev velikosti liposomov izničijo. Liposomes are spherical lipid vesicles constantly gaining ground in drug development as potential drug nanodelivery systems due to their ability to incorporate hydrophilic as well as lipophilic active ingredients. One of the major challenges is liposome production on an industrial scale where spray drying offers great potential. Stemming from the latter, the aim of this master's thesis was to evaluate the effects of different solvents and spray drying parameters on the production of liposomes with predetermined composition in order to obtain information on the possibility of transferring method to the production level. Based on literature and experiments we found suitable solvents for dissolving phospholipids (distearoyl phosphatidylcholine.(DSPC), distearoyl phosphatidylglycerole sodium salt (DSPG-Na)) and cholesterol. Liposomes were prepared by spray drying the lipid dispersion at varying parameters (air flow rate, feed rate and inlet temperature). The spray dried product was rehydrated in aqueous medium and the resulting liposomes were extruded through polycarbonate membrane. Thermal analysis was performed on spray dry powder and hydrodynamic diameter, polydispersity index and zeta potential of liposomes were measured. In experimental work and data analysis, we followed the principle of experimental design which allows us to obtain maximum amount of information for process and end product evaluation on a small number of experiments. Based on excipients solubility and ICH guidelines two solvents were selected for spray drying experiments: a mixture of dichloromethane and methanol in 1:1 volume ratio and methanol. The process of dissolving DSPG-Na was accelerated by heating the dispersion to 40 °C. By analysing the resulting liposomes, we found that their properties were influenced by two spray drying parameters. Higher process yield was obtained at lower air flow rate and smaller liposomes were obtained if the inlet gas temperature was raised. The diameter of the resulting liposomes was about 800 nm and decreased to 150 nm after extrusion, while zeta potential remained the same in both cases. The absence of solvent residue in dry product was proved by thermal analysis of samples. The key finding of the master's thesis was that by extrusion of liposomes the effects of spray-drying parameters on the size and polydispersity index of liposomes are practically eliminated.

U disertaciji je izvršena karakterizacija sliv nosioca fleksoštamparskih formi i predstavljena su istraživanja uticaja promenemehaničkih i adhezivnih svojstava slivova na parametre kvalitetaštampe kartonske ambalaže. Korišćene su dve grupe samolepljivihslivova (potpuno novi i slivovi korišćeni za štampu 5.000.000 mmaterijala). Ciljevi istraživanja su povećanje predvidivosti ikonstantnosti kvaliteta štampanog proizvoda i procesa proizvodnjekartonske ambalaže, formiranje preporuka za upotrebu slivovarazličitih svojstava i nivoa eksploatisanosti i otkrivanje u kojimfazama i kojim procesima dolazi do promena svojstava slivova., Research presented in this dissertation includes characterization offlexographic sleeves and the study of the influence of the changes inmechanical and adhesive properties of the sleeves on print qualityparameters of the cardboard packaging. Two groups of self-adhesive sleeveswere used (entirely new and sleeves used for printing of 5.000.000 m ofmaterial). Aims of the research are the increase in predictability and stabilityof the printed product quality and the production process of cardboardpackaging, forming of the recommendations for the use of sleeves withdifferent properties and levels of exploitation, as well as defining the phasesand processes responsible for the changes in sleeve properties.

V teoretičnem delu naloge smo opisali sestavo, izdelavo ter lastnosti polimernega kompozita. Definirali smo potencialne napake v kompozitu ter podrobneje opisali proces izdelave z avtoklavom. V zaključni nalogi so predstavljeni tudi teoretični izračuni vzdolžne in prečne natezne trdnosti kompozita z usmerjenimi vlakni v odvisnosti od volumskega deleža vlaken. Prikazali smo razliko vzdolžne in prečne natezne trdnosti glede na volumski delež vlaken ter potrdili, da je vzdolžna natezna trdnost kompozita proporcionalna volumskemu deležu vlaken. Ugotovili smo tudi da prečna natezna trdnost z volumskim deležem večjim od 90% eksponentno naraste, pod tem deležem pa jo močno definira trdnost matrice. In the theoretical part of the thesis, we described the composition, manufacture and properties of the polymer composite. We also defined potential defects in the composite and described the autoclave manufacturing process in more detail. The final paper also presents the theoretical calculations of the longitudinal and transverse tensile strength of a composite with oriented fibers depending on the volume fraction of fibers. We presented the difference between longitudinal and transverse tensile strength with respect to the volume fraction of fibers and confirmed that the longitudinal tensile strength of the composite is proportional to the volume fraction of fibers. We also found that the transverse tensile strength increases exponentially with a volume fraction greater than 90%, and below this proportion it is strongly defined by the strength of the matrix.

Majoneza je prehrambeni proizvod koji predstavlja emulziju tipa ulje-voda. Reološka svojstva su bitan čimbenik u definiranju parametara kakvoće hrane. Cilj ovog rada bio je ispitati utjecaj dodatka meda i procesnih parametara homogenizacije na reološka svojstva majoneze. Istraživan je utjecaj vremena homogenizacije i utjecaj brzine rotora homogenizatora na promjenu reoloških svojstava majoneze. Mjerenje reoloških svojstava majoneze provedeno je na rotacijskom viskozimetru pri temperaturi 25°C. Iz eksperimentalnih podataka mjerenja izračunati su reološki parameri: prividna viskoznost, koeficijent konzistencije i indeks tečenja. Rezultati istraživanja pokazuju da vrsta meda, kao i vrijeme homogenizacije i brzina rotora, utječu na reološka svojstva majoneze. Mayonnaise is a food product that is an oil-in-water emulsion. Rheological properties are an important factor in defining food quality parameters. The aim of this study was to examine the influence of the addition of honey and the process of homogenization on the rheological properties of mayonnaise. The research was based on the influence of homogenization time and homogenizer rotor speed on changes in the rheological properties of mayonnaise. Measuring rheological properties of mayonnasie was conducted by rotary viscometer at 25°C. The parameters were calculated based on these experimental study mesurements: apparent viscosity, consistency coefficient and flow index. Results of this study have shown that the type of honey, as well as the time of homogenisation and rotor speed, have an influence on rheological properties of mayonnaise.

V okviru magistrske naloge je bila izvedena optimizacija procesa injekcijskega brizganja izbranega izdelka iz polimernega materiala. Cilj optimizacije je bil doseči krajši čas proizvodnega cikla in ugotoviti vpliv šestih izbranih procesnih parametrov na dimenzije izdelka. V magistrski nalogi so predstavljene teoretične osnove procesa injekcijskega brizganja termoplastov, polimerni materiali in njihovi skrčki ter načrtovanje eksperimentov. Opisan je uporabljen sistem material – orodje – stroj, planiranje in izvedba eksperimenta, optimizacija procesnih parametrov in analiza rezultatov materialnih skrčkov. Optimizacija je bila izvedena po metodi načrtovanja eksperimentov z uporabo L27 Taguchijeve ortogonalne matrike. Velikost predelovalnega skrčka materiala polioksimetilen Hostaform smo določali na podlagi meritev orodnih vložkov in meritev izdelkov. In this Master's thesis, the injection molding process optimization of the chosen product was performed. The optimization objective was to achieve a shorter cycle time and to understand the effect of six injection molding process parameters on part dimensions. The thesis presents the theoretical foundation of the thermoplastic injection molding process, polymeric materials and their shrinkage and the design of experiments. It also includes the description of chosen system material – tool – machine, planning and execution of the experiment, process parameters optimization and analysis of material shrinkage results. Process optimization was performed by design of experiments method with L27 Taguchi orthogonal array. To determine molding shrinkage value of a polyoxymethylene Hostaform polymer measurements of mold cavities and parts were performed.

With recent developments in additive manufacturing (AM), new possibilities for fabricating smart structures have emerged. Recently, single-process fused-filament fabrication (FFF) sensors for dynamic mechanical quantities have been presented. Sensors measuring dynamic mechanical quantities, like strain, force, and acceleration, typically require conductive filaments with a relatively high electrical resistivity. For fully embedded sensors in single-process FFF dynamic structures, the connecting electrical wires also need to be printed. In contrast to the sensors, the connecting electrical wires have to have a relatively low resistivity, which is limited by the availability of highly conductive FFF materials and FFF process conditions. This study looks at the Electrifi filament for applications in printed electrical conductors. The effect of the printing-process parameters on the electrical performance is thoroughly investigated (six parameters, &gt, 40 parameter values, &gt, 200 conductive samples) to find the highest conductivity of the printed conductors. In addition, conductor embedding and post-printing heating of the conductive material are researched. The experimental results helped us to understand the mechanisms of the conductive network&rsquo, s formation and its degradation. With the insight gained, the optimal printing strategy resulted in a resistivity that was approx. 40% lower than the nominal value of the filament. With a new insight into the electrical behavior of the conductive material, process optimizations and new design strategies can be implemented for the single-process FFF of functional smart structures.

U ovom radu istraživan je utjecaj procesnih parametara prešanja sikavice na efikasnost proizvodnje hladno prešanog ulja te njegovu kvalitetu. Prije prešanja određen je udio ulja u sjemenkama sikavice (26,06 %). Prešanje sjemenki sikavice provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem sikavice dobivena su tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom procesa prešanja mijenjali su se procesni parametri: temperatura grijača glave preše kod izlaza pogače, frekvencija elektromotora i nastavak koji regulira veličinu otvora glave preše. Nakon završetka prešanja provedeno je prirodno taloženje od 14 dana dobivenog sirovog ulja, a potom vakuum filtracija. Primjenom standardnih metoda određeni su parametri kvalitete ulja: slobodne masne kiseline, peroksidni broj, udio vlage i isparljivih tvari te udio netopljivih nečistoda. Metodom po Soxhlet-u određivana je količina ulja u sjemenkama i zaostalog ulja u pogači kako bi se odredila efikasnost proizvodnje hladno prešanog ulja sikavice. Rezultati pokazuju da je primjenom nastavka za izlaz pogače promjera 10 mm, frekvencije elektromotora 25 Hz i temperature zagrijavanja glave preše 110 °C dobiven vedi volumen sirovog i hladno prešanog ulja sikavice, niži udio zaostalog ulja u pogači te vedi stupanj djelovanja preše. In this study we have monitored the influence of process parameters on the efficiency of the pressing Milk thistle seed production of cold pressed oil and its quality. Before pressing, the oil content of Milk thistle seeds was determined (26.06%). Milk thistle seeds pressing was carried out on laboratory screw press for production of cold pressed vegetable oils. Three products were obtained by pressing Milk thistle seeds: unpirified crued oil, oil sludge and cake. During the pressing process, the process parameters changed: temperature pf the press heating head at the outlet of cake, the frequency of the electric motors and the extension that regulates the size of the opening press head. After the process of pressing, natural sedimentation of 14 days and vacuum filtration were conducted on unpurified crude oil. By using standard methods we determineted the parametars of oil quality: free faty acid, peroxide value, the proportion of moisture and volatile matter and insoluble impuritie. The amount of oil in the seeds and residual oil in the cake was determined by the Soxhlet method to determine the production efficiency of cold-pressed Milk thistle oil. After applaying the 10 mm press head for cake outcome, 20 Hz frequency of electric motors, and 110 °C heating temperature of press head, the bigger volume of crude and Milk thistle oil was obtained as well as smaller volume of residual oil in the cake and larger level of press operation.

Elektrokemijsko galvaniziranje je na mikroskopskem nivoju sestavljeno iz štirih procesov: prenos naboja, masni transport, kemijske reakcije in kristalizacija. Pri galvaniziranju je število vhodnih parametrov veliko, najbolj pomembni izmed njih pa so tok, napetost, čas in koncentracije snovi v raztopini. V tej diplomski nalogi je preučen vpliv koncentracije cinka, natrijevega hidroksida in niklja na lastnosti galvanskega sloja cink-niklja, eksperimentalno določena pa je tudi učinkovitost procesa. Ti vplivi so preučeni s pomočjo eksperimentalnega dela v laboratoriju in statistično obdelavo teh podatkov ter podatkov iz proizvodnje. Electrochemical galvanization is composed of four processes at the microscopic level: charge transfer, mass transport, chemical reactions and crystallization. There are many input galvanization parameters, with the most important being electric current, voltage, time and concentrations of substances in the solution. This thesis studies the effects of the concentrations of zinc, sodium hydroxide and nickel on the properties of the galvanic layer of zinc-nickel. The efficiency of the galvanization process is also determined. These effects are studied with the help of experimental work in the laboratory and with statistical analysis of data gained from the laboratory and production.

The paper provides a description of an annular laser beam based direct wire deposition head, which can be used to perform controllable, simultaneous, and symmetrical heating of both the workpiece surface and the axially fed wire. In order to characterize the proportion of energy delivered to the workpiece and fed wire, respectively, a new process parameter, referred to as the workpiece illumination proportion, has been introduced, which is defined as the percentage of the annular laser beam power incident on the workpiece surface. The influence of this newly defined illumination parameter on the process outcome was characterized, based on single-layer deposition experiments using a 0.6 mm diameter nickel wire which was fed onto a stainless steel workpiece. The results show that the geometry of the deposited layer is influenced, as well as by the conventional process parameters, also by the newly introduced workpiece illumination parameter, which also affects the process stability and its robustness.

Cilj ovog rada je ispitati utjecaj procesnih parametara hladnog prešanja sjemenki noćurka s kontinuiranom pužnom prešom na iskorištenje ulja. Prije prešanja određen je udio ulja u sjemenkama noćurka i udio vlage. Prešanjem sjemenki noćurka dobivena su tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom procesa prešanja mijenjali su se procesni parametri: veličina nastavka za izlazak pogače (8 mm, 10 mm, 12 mm), temperatura grijača glave preše kod izlaza pogače (90 °C, 100 °C, 110 °C) i frekvencija elektromotora (25 Hz, 30 Hz, 40 Hz). Nakon završetka prešanja provedeno je prirodno taloženje u trajanju 21 dan dobivenog sirovog ulja, a potom vakuum filtracija. Na proizvedenom hladno prešanom ulju noćurka određen su osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, udio vode i udio netopljivih nečistoća. Metodom po Soxhlet-u određena je količina ulja u sjemenkama i zaostalog ulja u pogači kako bi se odredila efikasnost proizvodnje hladno prešanog ulja noćurka. The aim of this master thesis is to examine how different process parameters of cold pressing of evening primrose seeds with continuous screw press influence oil utilization. Before pressing, the oil content in the primrose seeds (21,50 %) and moisture content (6,90%) were determined. By pressing primrose seeds, three products were obtained: crude oil, oil sludge and cake. During the pressing process, process parameters were changed: extension that regulates the size of the opening press head (8 mm, 10 mm, 12 mm), temperature of the press heating head at the outlet of cake (90 °C, 100 °C, 110 °C) and the frequency of electric motors (25 Hz, 30 Hz, 40 Hz). After pressing has finished, natural sedimentation of 21 days and vacuum filtration were conducted on crude oil. Basic quality parameters of produced cold-pressed primrose oil were determined: peroxide number, free faty acids, water content and the proportion of insoluble impurities. Based on Soxhlet method, the amount of oil in the seeds and the residual oil in the cake were determined in order to define the efficiency of the production of cold-pressed evening primrose oil.

U ovom radu istraživan je utjecaj procesnih parametara hladnog prešanja sjemenki crnog kima na proizvodnju ulja te njegovu kvalitetu. Prešanje sjemenki crnog kima provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja te su tako dobivena tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjani su procesni parametri: temperatura glave preše, brzina pužnice, te nastavak za izlaz pogače. Nakon prešanja provedeno je prirodno taloženje dobivenog sirovog ulja te filtriranje. Primjenom standardnih metoda određeni su parametri kvalitete ulja: peroksidni broj, slobodne masne kiseline, udio netopljivih nečistoća te udio vlage i hlapljivih tvari. Kako bi se odredila efikasnost proizvodnje hladno prešanog ulja crnog kima provedeno je ispitivanje udjela ulja u pogači metodom po Soxhlet-u. Rezultati pokazuju da je primjenom nastavka za izlaz pogače veličine 6 mm, temperature 110 °C te frekvencije elektromotora 20 Hz dobivena najveća količina sirovog i finalnog hladno prešanog ulja crnog kima. In this study we have monitored the influence of process parameters on the efficiency of the pressing black cumin seed production of cold pressed oil and its quality. Black cumin seeds pressing was carried out on laboratory screw press for production of cold pressed vegetable oils. Three products were obtained by pressing black cumin seeds: unpurified crude oil, oil sludge and cake. During the pressing process, the process parameters changed: temperature pf the press heating head at the outlet of cake, the frequency of the electric motors and the extension that regulates the size of the opening press head. After the process of pressing, natural sedimentation and vacuum filtration were conducted on unpurified crude oil. By using standard methods, we determined the parameters of oil quality: peroxide value, free fatty acid, the proportion of moisture and volatile matter and insoluble impurities. The amount of oil in the seeds and residual oil in the cake was determined by the Soxhlet method to determine the production efficiency of cold-pressed black cumin oil. The results show that the highest amount of crude and final cold-pressed black cumin oil was obtained by applying a 6 mm extension that regulates the size of the opening press head with a temperature of 110 ° C and a frequency of 20 Hz.

Za izradu mikrovlaknastih materijala elektroispredanjem iz taline korišten je polimer polilaktid (PLA). Elektroispredanju je prethodio dizajn 2D modela u Sel generatoru, pri čemu su izrađene tri skupine modela koji se međusobno razlikuju po geometriji (raspored filamenata: vertikalno, vertikalno/vodoravno ili vertikalno/vodoravno i pod kutom manjim od 90°) te gustoći filamenata (udaljenost između filamenata od 0, 5, 1 i 2 mm). PLA elektroispredanje je optimizirano vizualizacijom stabilnosti polimernog mlaza te podešavanjem procesnih parametara (električni napon, tlak zraka, temperatura, udaljenost mlaznice od kolektora). U radu je utvrđen utjecaj geometrije strukture te gustoće filamenata na vlačnu čvrstoću PLA elektroispredenih materijala. Rezultati su pokazali da se povećanjem gustoće filamenata smanjuje vlačna čvrstoća materijala te da kompleksnije geometrije strukture (raspored filamenata vertikalno, vodoravno i dijagonalno) daju bolja mehanička svojstva materijala, zbog većeg broja naslojenih filamenata ili pozicioniranja istih u više smjerova.

Zadatak diplomskog rada bio je ispitati utjecaj vrste pužnice i procesnih parametara prešanja sjemenki sikavice na iskorištenje hladno prešanog ulja. Hladno prešano ulje sikavice proizvedeno je na kontinuiranoj pužnoj preši. Ispitan je utjecaj dvije vrste pužnice sa različitom dubinom navoja. Prilikom procesa prešanja mijenjali su se procesni parametri: temperatura grijača glave preše, frekvencija elektromotora i nastavak za izlaz pogače. Na proizvedenom hladno prešanom ulju sikavice ispitani su osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, udio vode, udio netopljivih nečistoća i utvrđena je sukladnost s Pravilnikom o jestivim uljima i mastima. The aim of this research was to examine the influence of screw press type and process parameters of pressing Milk Thistle Seeds on the utillsation of cold pressed oil. Cold pressed Milk Thistle Seed oil was produced with a continuous screw press. The influence of two types of screw press with different thread depths was examined. During the pressing process, the process parameters were changed: temperature of the press heating head, the frequency of electric motor and output cake thickness. The basic quality parameters that were tested on the produced cold pressed Milk Thistle Seed oil: peroxide value, free faty acid, water content, proportion of insoluble impurities and compliance with the Ordinance on edible oils and fats was determined.

Zadatak diplomskog rada je ispitati utjecaj frekvencije elektromotora tijekom prešanja sjemenke konoplje sorte Finola na iskorištenje ulja. Na proizvedenom hladno prešanom konopljinom ulju ispitan je utjecaj dodatka prirodnih antioksidansa i sinergista na promjenu oksidacijske stabilnosti ili održivosti ulja. Od prirodnih antioksidansa korišteni su ekstrakt ružmarina, ekstrakt kadulje, ekstrakt maslinove komine i katehin. Kao sinergist korištene su askorbinska i limunska kiselina. Efikasnost antioksidansa i sinergista u stabilizaciji ulja određena je Schaal Oven testom oksidacijske stabilnosti kod konstantne temperature 63 °C. Rezultati ispitivanja stabilnosti ulja prikazani su vrijednostima peroksidnog broja tijekom šest dana provedbe testa. Rezultati ispitivanja pokazuju da se veće iskorištenje konopljinog ulja postiže kod manjeg nastavka za izlaz pogače, manje frekvencije elektromotora i veće temperature glave preše. Ekstrakt ružmarina u kombinaciji sa sinergistom askorbinskom kiselinom najbolje štiti ulje konoplje od oksidacijskog kvarenja. The aim of this thesis is to examine the influence of the frequency of electric motors during the pressing of hemp seed variety Finola on oil yield. The effect of the addition of natural antioxidants and synergists on altering the oxidative stability or sustainability of the oil was tested on the produced cold pressed hemp oil. Natural antioxidants used were rosemary extract, sage extract, olive pomace extract and catechin. Ascorbic and citric acids were used as synergists. The effectiveness of antioxidants and synergists in oil stabilization was determined by the Schaal Oven oxidation stability test at a constant temperature of 63 °C. The results of the oil stability test are shown by peroxide values during the six days of the test. Test results show that greater use of hemp oil is achieved with a smaller batch output, lower electric motor frequency and higher press head temperatures. Rosemary extract in combination with ascorbic acid synergist best protects hemp oil from oxidative spoilage.

Cannabis sativa L. je industrijska vrsta konoplje koja se već neko vrijeme uzgaja za potrebe tekstilne i prehrambene industrije. Njene sjemenke sadrže oko 30 % ulja, 20 % proteina, 20 % ugljikohidrata i značajne količine minerala, vitamina i prehrambenih vlakana. Cilj ovog rada bio je ispitati utjecaj procesnih parametara hladnog prešanja sjemenke konoplje sorte Finola. Ispitan je utjecaj temperature zagrijavanja glave preše, frekvencija elektromotora te veličine otvora pužne preše na iskorištenje i kvalitetu ulja. U proizvedenom ulju odredili su se sljedeći parametri kvalitete: peroksidni broj, slobodne masne kiseline, netopljive nečistoće i voda. Dobiveni rezultati pokazuju da se veće iskorištenje ulja dobije s nastavkom manjeg promjera, sa manjom frekvencijom elektromotora i sa većom temperaturom grijača glave preše. Cannabis sativa L. is a kind of industrial hemp grown for some time for the textile and food industry. Hemp seeds averagely contain about 30 % oil, 20 % protein, 20 % carbohydrates, and significant amounts of minerals, vitamins and dietary fibre. The objective of this study was to evaluate the influence of process parameters of cold pressed hemp seed variety Finola. The effects of temperature, temperature head presses, frequency, and nozzle size on oil recovery and quality were investigated. In obtained hemp oil the following parameters were analysed: peroxide value, free fatty acids, insoluble impurities and moisture content. The results show that a higher yield of oil was obtained with the extension of smaller diameter with a smaller frequency of electric motors and higher temperature of the press head heater.

Tema ovog završnog rada je dizajn i izrada 2D i 3D mikrovlaknastih materijala ciljane geometrije tehnikom elektroispredanja iz polimerne taline. U teorijskom dijelu rada dan je kratki pregled povijesti tehnike elektroispredanja te osnovni princip na kojemu se zasniva. Nastavlja se detaljnim osvrtom na tehniku elektroispredanja iz polimerne taline odnosno konfiguraciju uređaja, procesne čimbenike, prednosti u odnosu na tehniku elektroispredanja iz polimerne otopine, kao i područja primjene. Eksperimentalni dio obuhvaća detaljan opis postupka izrade mikrovlaknastih materijala iz polikaprolaktona (PCL) na uređaju za elektroispredanje iz polimerne taline, uz prethodnu pripremu 2D modela u programu “SEL program generator”. Preliminarni 2D modeli te njihovi odgovarajući elektroispredeni materijali omogućili su upoznavanje s alatima za modeliranje i radom uređaja sto je temelj za daljnju optimizaciju procesnih parametara kod modela složenijih geometrija. Složeniji modeli simuliraju mikroskopsku strukturu lista ananasa i vezivnog ljudskog tkiva mišića i kostiju, a naposljetku izrađen je 3D model mrežaste strukture cjevastog oblika.

Hladno prešano konopljino ulje je nerafinirano ulje dobiveno metodom prešanja s kontinuiranom pužnom prešom. Temperatura proizvedenog ulja prešanjem ne prelazi 50 °C što dovodi do očuvanja poželjnih nutrijenata ulja. Prešanjem se izdvaja 60–80 % sirovog ulja iz sjemena, koje se u svrhu izdvajanja netopljivih nečistoća podvrgava postupcima sedimentacije i filtracije. Ovakvo dobiveno hladno prešano ulje ima sačuvana prirodna svojstva (miris, okus, boja). U ovom radu istraživan je utjecaj procesnih parametara hladnog prešanja sjemenki konoplje sorte Finola na iskorištenje i kvalitetu ulja. Ispitivani su procesni parametri frekvencija elektromotora, veličina otvora glave preše za izlaz pogače i temperatura grijača glave preše. Rezultati istraživanja pokazuju da procesni parametri prešanja sjemenki konoplje utječu na iskorištenje ulja. Korištenjem manje frekvencije elektromotora, manjeg nastavka za izlaz pogače i veće temperature glave preše proizvedena je veća količina konopljinog ulja. Metodom po Soxhletu određen je udio ulja u sjemenkama i pogači, kako bi se odredila djelotvornost preše i optimalni procesni parametri prešanja za proizvodnju ulja. Cold – pressed hemp oil is unrefined oil obtained by pressing with a continuous screw press. Oil temperature in the cold – pressing process does not exceed 50 ° C, preserving the oils desirable nutrients. Pressing extracts 60 – 80 % of raw oil from the seeds, which, for the purpose of removing insoluble impurities , then undergoes processes of sedimentation and filtration. The recovered cold – pressed oil preserves its natural properties (smell, taste, colour). In this paper, we analysed the influence of process parameters in cold – pressing Finola – strain hemp seeds on oil yield and quality. Examined process parameters were cold – press electric motor frequency, nozzle size, and temperature of the output press head. The result of this research show that hemp seed pressing parameters affect oil utilization. Lower electric motor frequency, a smaller size press – nozzle, and higher temperature of the output press head yield a greater amount of hemp oil. Content of oil in the seeds and the cake was determined using the Soxhlet method, in order to ascertain the efficiency of cold – pressing, as well as the optimal pressing process parameters for oil production.

V okviru zaključne naloge smo spoznavali proces vakuumske infuzije s ciljem ugotavljanja vplivov procesnih parametrov na kakovost izdelanih plošč. Glavni cilj izvedenega eksperimenta je bil ugotoviti nabor parametrov za zagotavljanje najkrajšega proizvodnega časa ter obenem zagotoviti visoko kakovost plošč. Spreminjali smo presek dovodne cevke, temperaturo procesa ter obliko in orientacijo infuzijske tkanine. Za izdelavo kompozita smo uporabili tkanino iz enosmernih steklenih vlaken ter epoksi smolo. Mehanske lastnosti smo testirali s tri-točkovnim upogibnim preizkusom, pri čemer smo izmerili upogibno trdnost, modul elastičnosti in upogibno razteznost v vzdolžni in prečni smeri. Največji vpliv na hitrost infuzije sta imela delovna temperatura ter usmerjenost in oblika infuzijske mrežice. Ugotovili smo, da je najboljša kombinacija za dosego najkrajšega proizvodnega časa in obenem čim manjše zakasnitve impregnacijskih front delovna temperatura 35 C ter zmanjšanje velikosti infuzijske mrežice na sesalni strani. Z upogibnim preizkusom vzorcev smo ugotovili, da se zaradi zmanjševanja debeline plošč od polnilne do sesalne strani povečuje modul elastičnosti in upogibna trdnost. Sprememba procesnih parametrov v raziskanem območju je imela signifikantni vpliv tudi na prečno trdnost plošč, ni pa imela večjega vpliva na vzdolžno trdnost. In the final thesis, we researched the process of vacuum infusion with the aim of determining the influence of process parameters on the quality of the manufactured panels. The main objective of the experiment was to determine a set of parameters to ensure the shortest production time, while at the same time ensuring high quality of the plates. We changed the cross section of the delivery tube, the process temperature, and the shape and orientation of the infusion mesh. One-way fiberglass fabric and epoxy resin were used to make the composite. Mechanical properties were tested with a three-point flexural test. We measured the flexural strength, modulus of elasticity, and flexural elongation in the longitudinal and transverse directions. The greatest influences on the speed of the infusion were the process temperature and the shape and size of the infusion mesh. We found that the best combination to achieve the shortest production time while minimizing the delay of the impregnation fronts is preheating the plates at 35°C and reducing the size of the infusion mesh on the suction side. By flexural testing of specimens, we found that because of the reduction in thickness of the plates from the filling to the suction side, the modulus of elasticity and flexural strength are increased. In the area studied, the change in the process parameters also had a significant effect on the transverse strength of the plates but had no significant effect on the longitudinal strength.

Oblikovno obločno navarjanje MIG/MAG predstavlja enega izmed postopkov dodajalnih tehnologij, ki zaradi svoje produktivnosti, vsestranskosti in cenovno dostopne opreme predstavlja velik potencial pri izdelavi velikih in hibridno izdelanih izdelkov. Naloga zajema pregled procesnih parametrov, ki omogočajo izdelavo ozke in ravne stene, navarjene na jekleno ploščo z varilno žico iz aluminijevega brona CuAl8. Na začetku so predstavljene osnove varjenja in spajkanja ter različni postopki in oprema za varjenje MIG/MAG. Raziskali smo vpliv različnih tehnoloških parametrov, na proces navarjanja, opravili smo analizo valovitosti stene in izkoristka navarjanja ter analizo stroškov. Ugotovili smo, da je za navarjanje aluminijevega brona najbolj primeren varilni proces CMT+P. Za izdelavo ozke in ravne stene pa je poleg ustreznih varilnih parametrov ključnega pomena medvarkovna temperatura, čistoča materiala, fine nastavitve na začetku in koncu varjenja ter pravilna izbira poti in hitrosti varjenja. Z opravljeno analizo smo določili stroške ter izkoristek navarjanja in valovitost stene. MIG/MAG wire are additive manufacturing is one of many additive technologies which is universal and affordable regarding investment costs and offers a huge potencial in producing bigger and hybrid made parts. This thesis covers defining of process parameters for making thin and streight wall cladded on a mild steel plate with aluminium bronze CuAl8 welding wire. In the first part of thesis we presented the basics of brazing and welding and also the different welding processes and equipment for MIG/MAG welding. We have researched the affects of different technological parameters on cladding process we made analysis of the wall shape, efficiency of cladding and process costs. We found out that for cladding aluminium bronze the welding proces CMT+P works best, but for making thin, streight wall besides the right welding parameters also the sample interpass temperature, cleanliness, fine adjustments on starts and stops of the welds and the correct welding path and speed are crucial. With the analysis made we determined the consumables costs, efficiency of cladding and wall shape.

Izum se odnosi na uređaj za mjerenja procesnih parametara i određivanje struktura tehnoloških operacija koji se sastoji od računala za sinkronizaciju rada elemenata sustava, automatsko vođenje mjerenja, pohranjivanje, obradu i prikaz rezultata, A/D pretvornika, mjernog pojačala, infracrvenog refleksnog pretvornika za bezkontaktna mjerenja brzine vrtnje glavnog vratila stroja, mjernog pretvornika položaja gazila za regulaciju brzine rada stroja, aktivnog mikrovalnog ili pasivnog infracrvenog detektora pokreta, jednog dodatnog ulaza za prihvat podataka iz drugih mjernih sustava i sustava nadzora s pomoću barem dvije video kamere za tlocrtno i bokocrtno snimanje radnog mjesta.

In the paper a novel annular – ring shaped – laser beam cladding head and related cladding process are presented. In the cladding head a laser beam is shaped into an annular ring and guided coaxially with the powder tube disposing the powder jet in the centre of the focused annular laser beam ring. An experimental process feasibility analysis was performed using a Nd:YAG pulsed laser system with a maximal average power 250 W. Beside the known influencing parameters of laser cladding process including the powder mass flow, workpiece feeding velocity, and laser beam intensity, the important parameters related to the annular laser beam caustics were defined. The process feasibility and influence of the process parameters on powder catchment efficiency was analysed based on the cladding experiments of SS 316L powder on SS 304 workpiece material. The potential benefits related to the annular laser beam melt pool geometry and related powder catchment efficiency are discussed.