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CAM programiranje
No full textZavršni rad pod naslovom “CAM programiranje“ bavi se tematikom CAM programiranja i primjenom CNC glodalica i obradnih centara u suvremenoj industrijskoj proizvodnji. Rad uključuje teorijski pregled CNC strojeva, njihovih osnovnih značajki i podjela, s posebnim fokusom na troosne i petoosne strojeve. Detaljno je obrađen CAM softver Mastercam, uključujući pregled njegovog korisničkog sučelja, definiranje operacija obrade, prednosti i ograničenja. U praktičnom dijelu rada prikazan je primjer izrade izratka na CNC glodalici DMG MORI (CMX 800 V), gdje je prikazan postprocessing odnosno prilagodba programa iz Mastercama za obradu na glodalici te su opisani koraci od simulacije putanje alata do završne obrade.
Rezultati rada ističu važnost preciznog programiranja i optimizacije procesa obrade u postizanju visoke kvalitete i učinkovitosti u proizvodnji. Zaključak rada naglašava vrijednost CAM softvera u industrijskoj praksi, posebice u kontekstu suradnje s tvrtkom Elcon Geraetebau.The thesis titled "CAM Programming" deals with CAM programming and the application of CNC milling machines and machining centers in modern industrial production. The work includes a theoretical overview of CNC machines and their main features and classifications, focusing on three- and five-axis machines. The CAM software Mastercam is analyzed in detail, including an overview of its user interface, the definition of machining operations, advantages, and limitations. The practical part of the thesis presents an example of creating a workpiece on a DMG MORI CNC milling machine (CMX 800 V), demonstrating the postprocessing, i.e., the adaptation of the program from Mastercam for machining on the milling machine, and describes the steps from toolpath simulation to final machining. The results emphasize the importance of precise programming and process optimization in achieving high quality and efficiency in production. The conclusion highlights the value of CAM software in industrial practice, particularly in the context of collaboration with the company Elcon Geraetebau
SHIP CONSTRUCTION TECHNOLOGY DESIGN FOR SELECTED SHIPYARD
No full textU ovom diplomskom radu objašnjeno je projektiranje tehnologije gradnje putničkog broda za odabrano brodogradilište. Tehnologija je važan faktor u brodogradnji koja odlučuje kako, gdje i kada će se napraviti brod. Općenito je bio fokus na tehnologiju opremanja putničkog kruzera koja je poprilično zanimljiva za prezentirati u diplomskom radu dok je sama tehnologija izrade sekcija od predobrade do navoza objašnjena u osnovnim crtama.
U prvom dijelu rada općenito je definirano brodogradilište u kojem će se graditi brod te svi kriteriji koji su zadovoljeni za početak gradnje broda. Brod je podijeljen u tehnološke grupe i jedinice uz relevantnu projektnu dokumentaciju.
U drugom dijelu rada objašnjeno je razlika u opremanju broda na navozu i opremanju u opremnoj luci te koje su prednosti i nedostatci prilikom opremanja broda te je analizirano specifičnost opremanja putničkog broda u opremnoj luci i na navozu, još je tu dodan fokus na uranjeno opremanje u fazi predmontaže.
Treći dio rada objašnjava izradu i opremanje jedne karakteristične sekcije putničkog broda. Radi se o sekciji 101 odnosno krmi broda koja je specifična zbog opreme koja se nalazi na njoj ( propulzijskog sustava ). Objašnjena je izrada i strojna obrada sklopa sekcije do montaže na navoz.
Zadnji dio rada objašnjava nam tehnologiju montaže i opremanja sekcije sa propulzijskim sustavom. Objašnjena je razlika između modernog propulzijskog sustava sa električnom propulzijom u odnosu na klasični propulzijskih sustav. Prednosti i nedostatci jednog odnosno drugog sustava su defiinirani na kraju rada.In this thesis, the design of construction technology for a passenger ship at a selected shipyard is explained. Technology is a crucial factor in shipbuilding that determines how, where, and when a ship will be built. The focus was generally on the outfitting technology of a passenger cruise ship, which is quite interesting to present in a thesis, while the technology of section fabrication from preprocessing to launching is explained in basic terms.
The first part of the thesis generally defines the shipyard where the ship will be built and all the criteria that were met to commence ship construction. The ship is divided into technological groups and units along with the relevant project documentation.
The second part of the thesis explains the difference between outfitting the ship on the slipway and outfitting in the outfitting port, the advantages and disadvantages of ship outfitting are analyzed, and the specifics of outfitting a passenger ship in the outfitting port and on the slipway are examined. Additionally, there is a focus on early outfitting during the pre-assembly phase.
The third part of the thesis describes the fabrication and outfitting of a characteristic section of the passenger ship. This involves section 101, or the stern of the ship, which is unique due to the equipment it contains (the propulsion system). The fabrication and machining of the section assembly up to its installation on the slipway are explained.
The final part of the thesis explains the technology of assembly and outfitting of the section with the propulsion system. It clarifies the difference between a modern propulsion system with electric propulsion and a classic propulsion system. The advantages and disadvantages of each system are defined at the end of the thesis
ELECTRIC MOTORS IN THE AUTOMOTIVE INDUSTRY
No full textKrenuvši sa predstavljanjem principa rada motora i učinka struje i magnetizma na funkcioniranje motora prelazimo na upoznavanje pojedinačnih vrsta i podvrsta motora sa AC i DC napajanjem. Iskazuje se njihova konstrukcija, prednosti, mane i posebne značajke koje ih razlikuju od ostalih predstavljenih motora. Nakon predstavljanja motora zalazimo u pojedine tvrtke i modele električnih automobila koje se ističu na tržištu po funkcionalnosti, izgledu, dostupnosti i performansama. Uz modele naznačuju se i ostali električni motori koji se primjenjuju u automobilu a da nemaju utjecaj na sam pogon. Prikazivanjem grafičke razlike između performansi i efikasnosti električnih automobila i automobila sa unutarnjim izgaranjem prikazuje se i utjecaj na upotrebu električnih automobila na okoliš što ukratko zaključuje ovaj rad.Starting with the presentation of the principle of motor operation and the effect of current and magnetism on the operation of the motor, we move on to introducing individual types and subtypes of motors with AC and DC power supply. Their construction, advantages, disadvantages and special features that distinguish them from the other presented engines are presented. After presenting the engines, we go into individual companies and models of electric cars that stand out on the market in terms of functionality, appearance, availability and performance. In addition to the models, other electric motors are indicated that are used in the car that are not the power motors. By showing the graphic difference between the performance and efficiency of electric cars and cars with internal combustion and the impact of the use of electric cars on the environment the paper is concluded
Experimental strain analysis of polymer specimens under creep conditions
No full textOvaj diplomski rad pod nazivom "Eksperimentalna analiza deformacija polimernih uzoraka u uvjetima puzanja" bavi se istraživanjem mehaničkog ponašanja polimernih materijala pod dugotrajnim opterećenjem odnosno u uvjetima puzanja. S obzirom na sve veću primjenu polimera u raznim industrijama, razumijevanje njihovih dugotrajnih svojstava, kao što je puzanje, postaje sve važnije. Uz to, tehnike aditivne proizvodnje, posebno 3D ispis, donijele su revoluciju u načinu proizvodnje složenih geometrija, što dodatno naglašava potrebu za istraživanjem mehaničkih svojstava ovih materijala.
Glavni cilj ovog istraživanja bio je provesti eksperimentalnu analizu deformacija puzanja polimernih uzoraka pripremljenih tehnikom 3D ispisa. Cilj je bio pripremiti uzorke različitih polimernih materijala, provesti eksperimentalna ispitivanja puzanja na različitim razinama naprezanja te razviti i validirati analitičke modele, s posebnim naglaskom na Norton – Bailey model.
Eksperimentalna analiza provedena je na uzorcima pripremljenim tehnikom 3D ispisa. Uzorci su bili izloženi dugotrajnom opterećenju na 70 % naprezanja maksimalno postignute sile kako bi se proučilo njihovo ponašanje pri puzanju. Dobiveni eksperimentalni podaci korišteni su za validaciju analitičkih modela, pri čemu se posebno primjenljiv pokazao Norton - Bailey model.
Rezultati ispitivanja pokazali su da polimerni uzorci pokazuju različite stupnjeve deformacija ovisno o vrsti materijala i geometriji samog kompozita. Norton – Bailey model uspješno je opisao eksperimentalne podatke za većinu ispitivanih uzoraka, iako su uočena određena odstupanja koja ukazuju na potrebu za dodatnim istraživanjima i prilagodbama modela.
Validacija Norton – Bailey modela provedena je pomoću eksperimentalnih podataka. Usporedba eksperimentalnih rezultata i predikcija modela pokazala je dobro slaganje, što potvrđuje valjanost modela za predviđanje ponašanja polimernih materijala pri puzanju. Međutim, manja odstupanja ukazuju na potrebu za dodatnim prilagodbama modela.
Na temelju provedenih istraživanja može se zaključiti da su polimerni materijali izrađeni tehnikom 3D ispisa podložni puzanju, a njihovo ponašanje pri puzanju može se uspješno predvidjeti korištenjem analitičkih modela poput Norton – Bailey modela. Rezultati ovog rada pridonose razumijevanju dugotrajnih svojstava 3D ispisanih polimernih materijala, što je ključno za njihovu industrijsku primjenu i optimizaciju procesa proizvodnje.
Daljnja istraživanja trebala bi se usmjeriti na detaljniju analizu uzroka odstupanja između eksperimentalnih podataka i modela te na razvoj novih i poboljšanih modela za preciznije predviđanje ponašanja polimernih materijala pri puzanju. Također, istraživanje bi trebalo uključivati širi spektar materijala i uvjeta testiranja kako bi se dobili sveobuhvatniji rezultati.This thesis, titled "Experimental Analysis of Creep Deformations in Polymer Samples," focuses on the mechanical behaviour of polymer materials under long-term loading conditions, namely creep conditions. With the increasing use of polymers in various industries, understanding their long-term properties, such as creep, is becoming more crucial. Additionally, additive manufacturing techniques, particularly 3D printing, have revolutionized the production of complex geometries, further highlighting the need to investigate the mechanical properties of these materials.
The primary objective of this research was to conduct an experimental analysis of creep deformations in polymer samples prepared using 3D printing techniques. The study aimed to prepare samples of different polymer materials, perform experimental creep testing at various stress levels, and develop and validate analytical models, with a specific focus on the Norton-Bailey model.
Experimental analysis was carried out on samples prepared using 3D printing. The samples were subjected to long-term loading at 70 % of maximum stress level to study their creep behaviour. The experimental data obtained were used to validate the analytical models, particularly the Norton-Bailey model.
The results of the tests showed that polymer samples exhibit different degrees of deformation depending on the material type and composite structure. The Norton – Bailey model successfully described the experimental data for most of the tested samples, although some deviations were observed, indicating the need for further research and model adjustments.
The validation of the Norton – Bailey model was performed using experimental data. The comparison between experimental results and model predictions showed good agreement, confirming the validity of the model for predicting the creep behaviour of polymer materials. However, minor discrepancies observed suggest the need for further refinement of the model.
Based on the conducted research, it can be concluded that polymer materials made using 3D printing techniques are susceptible to creep, and their creep behaviour can be successfully predicted using analytical models like the Norton – Bailey model. The findings of this study contribute to the understanding of the long-term properties of 3D – printed polymer materials, which is crucial for their industrial application and optimization of the manufacturing process.
Further research should focus on a detailed analysis of the discrepancies between experimental data and models, and the development of new and improved models for more precise prediction of polymer creep behaviour. Additionally, the research should include a broader range of materials and testing conditions to obtain more comprehensive results
Automation of wastewater pumping station facilities
No full textU radu će se najprije definirati opseg podešavanja brzine vrtnje kao ključni element prilagodbe elektromotornih pogona radnom stroju. Nakon toga navest će se prilagodba pogona istosmjernim motorima uzimajući u obzir njihove različite vrste prema uzbudnom krugu. Potom će se obraditi prilagodba asinkronim motorima, te nakon toga sinkronim motorima. Konačno, opisat će se pokretači rotacijskih električnih strojeva. Navesti će se još nekoliko primjera višemotornih pogona, električnih osovina i kaskadnih spojeva aksinkronih motora.The paper will first define the scope of rotation speed adjustment as a key element of the adaptation of electric motor drives to the working machine. After that, the adaptation of drives to DC motors will be indicated, taking into account their different types according to the excitation circuit. Then adaptation to asynchronous motors, and then to synchronous motors, will be processed. Finally, the drivers of rotary electric machines will be described. A few more examples of multi-motor drives, electric shafts and cascade connections of asynchronous motors will be given
Arduino based photovoltaic system for dual-axis solar tracking
No full textU sklopu ovog završnog rada izrađen je solarni tragač s mogućnošću dvoosnog praćenja položaja
Sunca. Prvo su opisane sve komponente korištene pri izradi sustava. Nakon toga opisan je proces
izrade samog tragača, tj. opisan je postupak izrade kućišta, shema spajanja komponenti te opis
programskog koda sklopa. Završno, eksperimentom je uspoređena učinkovitost fiksnog
fotonaponskog sustava sa sustavom koji ima mogućnost dvoosnog praćenja položaja Sunca, te je na
temelju dobivenih mjerenja ustanovljena 24% veća učinkovitost sustava koji ima mogućnost praćenja
položaja Sunca.In this bachelors thesis, Arduino based tracker has been developed. First, all components used in the
system have been described. After that, the process of building the tracker has been described. In terms
of making of the housing, connection diagram of the system, and the development software. Finally,
through the experiment, the efficiency of the dual-axis solar tracker has been compared with the
efficiency of the fixed photovoltaic system, and the measured data indicates 24% greater efficiency
of the dual-axis solar tracker
ANALIZA OPSTRUJAVANJA OKO ČESTICE MIKROPLASTIKE
No full textCilj ovog rada jest usporedba analitičkih rezultata dobivenih iz Stokesovog zakona s rezultatima dobivenima numeričkom simulacijom. Na samom početku rada opisani su osnovni pojmovi mehanike fluida. Pojašnjeno je dobivanje Stokesovog zakona iz Navier Stokesovih jednadžbi. Nakon toga je objašnjena izrada 2D i 3D geometrije kao i izrada numeričke mreže. Prikazano je postavljanje nestacionarne simulacije u OpenFOAM-u te stacionarne simulacije Ansys Fluent-u. Izrađene su simulacije nerotirajuće čestice mikroplastike te simulacije s nekoliko različitih kutnih brzina rotacije čestice mikroplastike. Napravljena je analiza rezultata koja se temeljila na usporedbi podataka na središnjoj liniji. Odstupanja rezultata izračunata su kao srednje kvadratno odstupanje.The aim of this paper is to compare analytic results obtained from Stokes’ law with the results obtained by numerical simulation. At the very beginning of the work, the basic concepts of fluid mechanics are described. The derivation of Stokes’ law from the Navier Stokes equations is clarified. After that, the creation of 2D and 3D geometry as well as the creation of a numerical mesh was explained. The setup of unsteady simulation in OpenFOAM and steady simulation in Ansys Fluent is shown. Simulations were conducted for non-rotating microplastic particle and for particle with various angular velocities. An analysis of the results was performed, which was based on the comparison of data on the central line. The deviations of the results were calculated as the mean square deviation
