Necessity and effects of dynamic systems for railway wheel defect detection

State of railway vehicles highly influences transport safety due to vehicle derailments and in the same time worsens the quality of freight and passenger transportation. One of important elements that influence the state of railway vehicles is the wheel state. Wheel defects are common in railway transport. Therefore, timely defect detection is very important. This paper presents ways and effects of timely detection of wheel defects

Design and economic justification of group blanks application

Within the manufacturing process planning, blanks are either selected or designed, respectively forms of input material for the manufacture of products. Reviewed in this paper are three types of group blanks: group castings, group forgings manufactured by closed die forging and free forging, and group blanks manufactured by pressing melted metal in casts. The paper also presents requisites for design and evaluation of economic justification of group blanks application

Mathematical identification of influential parameters on the elastic buckling of variable geometry plate

The problem of elastic stability of plates with square, rectangular, and circular holes as well as slotted holes was discussed. The existence of the hole reduces the deformation energy of the plate and it affects the redistribution of stress flow in comparison to a uniform plate which causes a change of the external operation of compressive forces. The distribution of compressive force is defined as the approximate model of plane state of stress. The significant parameters of elastic stability compared to the uniform plate, including the dominant role of the shape, size, and orientation of the hole were identified. Comparative analysis of the shape of the hole was carried out on the data from the literature, which are based on different approaches and methods. Qualitative and quantitative accordance of the results has been found out and it verifies exposed methodology as applicable in the study of the phenomenon of elastic stability. Sensitivity factor is defined that is proportional to the reciprocal value of the buckling coefficient and it is a measure of sensitivity of plate to the existence of the hole. Mechanism of loss of stability is interpreted through the absorption of the external operation, induced by the shape of the hole

Dizajn i ekonomska opravdanost primjene grupnih pripremaka

Within the manufacturing process planning, blanks are either selected or designed, respectively forms of input material for the manufacture of products. Reviewed in this paper are three types of group blanks: group castings, group forgings manufactured by closed die forging and free forging, and group blanks manufactured by pressing melted metal in casts. The paper also presents requisites for design and evaluation of economic justification of group blanks application.U okviru projektiranja tehnoloških procesa vrši se izbor ili projektiranje pripremaka, odnosno oblika ulaznog materijala za izradu proizvoda. U radu se prikazuju osnovne vrste grupnih pripremaka kao što su grupni odljevci, grupni otkivci proizvedeni u zatvorenim kalupima i hladnim zapreminskim oblikovanjem, slobodnim kovanjem, kao i grupni pripremci proizvedeni prešanjem rastopljenog metala u kalupima. U radu se, također, daju podloge za projektiranje i ocjenu ekonomske opravdanosti primjene grupnih pripremaka

Potreba i efekti dinamičkih sustava za detekciju defekata točkova željezničkih vozila

State of railway vehicles highly influences transport safety due to vehicle derailments and in the same time worsens the quality of freight and passenger transportation. One of important elements that influence the state of railway vehicles is the wheel state. Wheel defects are common in railway transport. Therefore, timely defect detection is very important. This paper presents ways and effects of timely detection of wheel defects.Stanje željezničkih vozila bitno utječe na sigurnost prometa zbog rizika iskliznuća i istovremeno smanjuje kvalitet prevoza robe i putnika. Jedan od bitnijih čimbenika koji utječu na stanje željezničkih vozila jeste stanje točkova. Defekti točkova su česta pojava u željezničkom prometu. Iz tog razloga, veoma bitno je pravovremeno otkrivanje defekata. U ovom radu su prezentirani načini i učinci pravovremenog detektiranja defekata točkova

Tehnoekonomska metoda za ocjenu i izbor fleksibilnih tehnoloških sustava (FTS)

To find best FMS solutions, experts use numerous multicriteria methods for evaluation and ranking, methods based on artificial intelligence, and multicriteria optimization methods. Presented in this paper is a developed technoeconomic method for evaluation and selection of FMS based on productivity. The method is based on group technology (GT) process planning.Za izbor najpovoljnijih rješenja FTS koriste se brojne multikriterijske ekspertske metode vrijednovanja i rangiranja, metode ustrojene na primjeni umjetne inteligencije, kao i metode multikriterijske optimizacije. U ovom radu prikazuje se razvijena tehnoekonomska metoda za ocjenu i izbor FTS na temelju proizvodnosti. Metoda je utemeljena na tehnološkim osnovama koje se obrazuju na principima grupne tehnologije (GT)

Techno-economic method for evaluation and selection of flexible manufacturing systems (FMS)

To find best FMS solutions, experts use numerous multicriteria methods for evaluation and ranking, methods based on artificial intelligence, and multicriteria optimization methods. Presented in this paper is a developed technoeconomic method for evaluation and selection of FMS based on productivity. The method is based on group technology (GT) process planning

Development of the computer-aided process planning (CAPP) system for polymer injection molds manufacturing

Beginning of production and selling of polymer products largely depends on mold manufacturing. The costs of mold manufacturing have significant share in the final price of a product. The best way to improve and rationalize polymer injection molds production process is by doing mold design automation and manufacturing process planning automation. This paper reviews development of a dedicated process planning system for manufacturing of the mold for injection molding, which integrates computer-aided design (CAD), computer-aided process planning (CAPP) and computer-aided manufacturing (CAM) technologies

Modeliranje odljevaka u RPPP sustavu za dijelove klipno-cilindarskog sklopa motora sa unutarnjim sagorjeva njem

Development of information technology industry provided great possibilities in the area of integration of different CAx systems, such as CAD, CAM, CAE and others. In order to successfully link systems of automated-design (or Computer Aided Design - CAD) with automated manufacturing systems (or Computer Aided Manufacturing – CAM), automation of manufacturing process planning is needed, i.e. CAPP (Computer-Aided Process Planning) systems can bridge a gap between design and manufacturing. In this paper is shown design of casting blanks in CAPP system for parts of piston-cylinder assembly of internal combustion engines in a manufacturing system.Dostignuta razina razvoja informacijskih tehnologija omogućila je značajne rezultate u području integracije različitih CAx sustava kao što su CAD, CAM, CAE i drugi programski sustavi. Da bi se uspješno povezali sustavi automatiziranog projektiranja proizvoda, odnosno CAD sustavi i sustavi automatizirane proizvodnje, odnosno CAM sustavi, potrebna je automatizacija projektiranja tehnološkog procesa izrade, dakle CAPP sustavi, koji predstavljaju most između projektiranja i proizvodnje. U ovom radu se prikazuje modeliranje odljevaka u integriranom CAPP sustavu za dijelove klipno-cilindarskog sklopa motora sa unutarnjim sagorjevanjem u jednom proizvodnom sustavu