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Original scientific paper The article presents theoretical notions related to assembly sequence planning in the process of elements design engineering and design for machines assembly. Basic modules of the designed method are described and shown on simple examples. The concept is based on the assumption that the method should help the engineer-constructor in specifying the best assembly sequence, taking into account the principles of design for assembly at an early stage of development of the product design. The second part of the article explains how to use the described method on the basis of an authentic industrial situation. Keywords: assembly sequence planning; design for assembly; engineering design Planiranje i analiza toka operacija montaže u projektiranju -Dio I: MetodaIzvorni znanstveni članak U radu se predstavljaju teorijski pojmovi vezani uz planiranje toka operacija montaže u postupku konstruiranja elemenata i projektiranja za montažu strojeva. Opisani su osnovni moduli projektirane metode i prikazani na jednostavnim primjerima. Pristup se zasniva na pretpostavci da bi ta metoda trebala pomoći inženjeru-konstruktoru u određivanju najboljeg toka operacija montaže, uzimajući u obzir principe konstruiranja za montažu u ranom stadiju razvoja projekta proizvoda. Drugi dio rada objašnjava kako primijeniti opisanu metodu u autentičnoj industrijskoj situaciji.Ključne riječi: planiranje toka operacija montaže; projektiranje za montažu; tehnički projekt

This paper presents the assumptions of a thermodynamic equation of state for polymers according to the Renner model. The experiments involved extruding a biocomposite based on poly(butylene succinate) that was filled with ground wheat bran with its size not exceeding 200 μm. The biocomposite was produced in pellet form with three different contents by weight of wheat bran, i.e., 10%, 30% and 50%. All specimens were examined for their thermodynamic p-v-T characteristics. Taking advantage of the SimFit module of Cadmould 3D-F, experimental results were used to determine the coefficients of thermodynamic equation of state for the tested biocomposite according to the Renner model. The coefficients were then used to calculate transition temperature and to create diagrams illustrating the relationship between pressure, temperature and specific volume for the tested biocomposite. The obtained results can serve as a basis for assessing the suitability of the biocomposite for injection molding, selecting technological parameters of this process, as well as for analyzing shrinkage and defects of injection-molded parts.

This article describes the studies of the mechanical properties of the martensitic structure of C45 steel, obtained as a result of heat treatment. This steel was subjected to high tempering, within the temperature range of 500÷700°C (every 50°C) and for various exposure times, from 15 minutes to 23 hours. Moreover, martensitic steel was subjected to tests by quenching at a temperature of 850°C for 20 minutes and then tempering it for 1 hour, within the temperature range of 50÷800°C (every 50°C). The resulting steel samples were subjected to strength tests, that is, to tensile and hardness tests and also to tests on the micro-structure. The results of these studies are presented and discussed, in detail, in terms of their practical application.

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