MM Science Journal, March 2017

METHOD OF DETERMINATION OF THE BOUNDARY STRENGTH OF PRESSED SHEETS OF CAR BODIES FOR CATEGORIES TO 1300 CM3

VILIAM CACKO, IVETA ONDEROVA, LUBOMIR SOOS, JURAJ ONDRUSKA, GREGOR IZRAEL
Keywords: boundary strength | car bodies | steel | Grubbs test | non-homogenous material

Pressed steel sheets, in this case compacted vehicle bodies represent the structure diversity of the non-homogeneous material. There is necessity to determine the shear strength for the development of the construction of new processing equipment (cutting) of steel sheets. To calculate the shear strength it is necessary to know the ultimate firmness of the material. For homogeneous materials this paramet (…)

SUBSTITUTION OF CEMENT BY MICRO-MILLED RECYCLED CONCRETE IN COLD RECYCLED ASPHALT MIXES

ZUZANA CIZKOVA, JAN VALENTIN
Keywords: micro-milled concrete | recycled concrete | mechanical activation | active filler | cold recycled asphalt pavement | moisture susceptibility | cement

Besides the bituminous binder (foamed bitumen or bituminous emulsion) cement is often added into the cold recycled mixes as well. That is because cement improves moisture susceptibility and provides sufficient strength and stiffness especially during the early stage of mix curing. This article is focused on investigation of the potential of cement substitution by the micro-milled recycled concrete. The (…)

THE POSSIBILITY OF USING RECYCLED POLYPROPYLENE SUPOL HT345E

LUDOVIT KOLLATH, JANA KRCOVA, ERNEST GONDAR
Keywords: extruder | polypropylene | wood sawdust | particles

Exploitation of plastic waste is current issue in part of recycling in this present. Current recycling appears possibility of manufacturing of composite materials WPC (woodplastic composite). While a few decades ago as a plastic matrix used thermosets, currently often is using thermoplastics. The reason among other things is also able recycling these composite materials. The most common example exploita (…)

MUNICIPAL SOLID WASTE GASIFICATION WITHIN WASTE-TO-ENERGY PROCESSING

MAREK BALAS, MARTIN LISY, PETR KRACIK, JIRI POSPISIL
Keywords: municipal solid waste | gasification | pyrolysis | waste-to-energy

This paper discusses theoretical assets and liabilities of a use of advanced thermal technologies within waste-to-energy (WTE) processing. Gasification and pyrolysis are compared to conventional incineration. Major part of the paper deals with results of gasification experiments: various wastes were gasified within a fluid generator with a circulating fluidized bed. The results were later compared. Lowe (…)

EXPERIMENTAL EVALUATION OF THE QUALITY OF SURFACE AFTER WEDM FOR STEEL X210CR12

KATERINA MOURALOVA, JIRI KOVAR, MILAN KALIVODA, MILAN DVORAK
Keywords: WEDM | electrical discharge machining | steel X210Cr12 | quality of surface | Analysis of the chemical composition

Wire electrical discharge machining (WEDM) is a non-conventional machining technology which uses electrical impulses between two electrodes to cut materials. The long-term trend of increasing accuracy and surface finish quality leads to the necessity of its detailed examination. The study deals with the evaluation of the surface morphology by electron microscopy (SEM) and chemical composition analysis ( (…)

STRENGTH ANALYSIS OF PIN CONNECTIONS USING COMPUTER AIDED SYSTEMS

PETR BERNARDIN, VACLAVA LASOVA, FRANTISEK SEDLACEK
Keywords: pin | connection | finite element analysis | strength check | permissible stress

The aim of this work was to analyse the options for predicting pin connections, using modern computer aided systems. These advanced methods include Special-Purpose Programs and Finite Element Analysis, which fundamentally differ in their duration and precision of results. Some of these methods allow calculation including the influence of the force and pin position, position of the stiffness centre, and (…)