MM Science Journal, June 2017

FEM-AIDED MATERIALS SELECTION OPTIMIZATION

PAVEL FLORIAN, IVANA MAZINOVA, MARTIN KRATOCHVIL, FILIP HRDLICKA
Keywords: materials selection optimization; material indices; ANSYS; FEM; CES EduPack; DOE | Matlab

During the design process materials selection is usually carried out unsystematically, selection is mostly based on previous experience. Professor M. Ashby developed a methodology of materials selection optimization based on material indexes. Our aim is to link this methodology with optimization interface of software ANSYS. This link allows solving complicated multi-criteria problems that cannot be solv (…)

INFLUENCE OF MACHINED SURFACE SHAPE ON LIGHT ABSORPTION

ONDREJ BILEK, MARTIN VASINA
Keywords: CNC machining | surface shape | light absorbance | groove | illuminance | computer simulation

There are different factors that have influence on light absorption of a given material, e.g. material colour and thickness, angle of light incidence, surface shape, roughness, porosity and surface cleanliness. This paper is focused on material ability to absorb light. For this reason, different surface shapes of a polyvinylchloride material were produced on CNC milling machine. There were investigated (…)

QUALITY MANAGEMENT MAINTENANCE OF AIR TRAFFIC

NAQIB DANESHJO, MILAN MAJERNIK, ENAYAT DANISHJOO, JANA KRIVOSUDSKA
Keywords: quality management systems | maintenance | logistics | optimization

The authors within the scientific contribution present the maintenance task to provide aircrafts ready for flight. Engineering standards and the framework of international and national air law are fundamental for efficient and reliable aircraft maintenance services. The present thesis provides an insight into general maintenance fundamentals, legal requirements and into actual organization of this busin (…)

FAILURE PREVENTION IN MAINTENANCE SERVICES AND LOGISTICS

CHRISTIAN DIETRICH, NAQIB DANESHJO, MIRWAJS DANISHJOO
Keywords: logistics chains | quantitative | maintenance | quality | real time | quality interfaces | flexibility management

The authors within the scientific contribution present the Preventive and non-routine maintenance activities on aircraft demand for varying priorities, service provider have to ensure a maximum of flexibility. Key competences for Maintenance, repair and overhaul (MRO) operators are permanent availability, a short respond time, continuous access to current information and real-time process monitoring for (…)

NEW MATERIALS CHARACTERIZATION APPROACHES IN COMPUTER AIDED DESIGN

JAN DZUGAN, ANTONIN PRANTL, MARTIN RUND, MIROSLAV URBANEK, RADEK PROCHAZKA, VACLAV KUBEC
Keywords: ductile damage | strain path influence | small size testing | triaxiality

Improvements in computer simulation, materials characterization and lowering of design safety margins leads to significant decrease of components mass. In order to maintain functions and increase components service reliability while reducing their mass, new approaches describing closer material behaviour and in service component properties are applied. The current paper is shoving recent trends contribu (…)

DETERMINATION OF CERTAIN PARAMETERS OF A BEARING

MARTIN KRATOCHVIL
Keywords: ball bearing | load spectrum | optimization | determination | selection

The article deals with the development of a more accurate method for determining certain parameters of a bearing in the early stages of the engineering design process. Using the traditional approach, the parameters of the given parts are estimated by experience. Another method is to make a simple estimation of basic static or basic dynamic load rating, which is inaccurate if is applied. Following this s (…)

OPTIMIZATION OF THE HCR GEARING FROM PITTING DAMAGE POINT OF VIEW

MIROSLAV VERES, MIROSLAV BOSANSKY
Keywords: HCR gearing | GPSO algorithm | contact | ratio coefficient | pitting | slip ratio | optimizing of the geometric parameters

Pitting damage as a result of contact stress on the gears teeth flanks is one of the most important problems needing to be solved in the process of gearing design and calculation. According to current valid standards, such calculations can be resolved with a high level of reliability for all the usual gearing types. However, suitable calculations for HCR gears have not been adequately researched to date (…)

LOAD CONTROL POSSIBILITIES OF EXPERIMENTAL LINEAR DRIVE

KAMIL SUBRT, PAVEL HOUSKA, RADEK KNOFLICEK
Keywords: Experiment | pressure control | control | pneumatics | Ecodesign

The article describes a load drive extension for an existing laboratory experimental equipment for testing of linear drives with ball screw. The main aim is to simulate the static component of the load, and therefore the pneumatic actuator has been selected. The control elements (electro-pneumatic valves) and appropriate control strategies are also investigated. The experiment was performed with two val (…)

PASSIVE TORQUE SIMULATION OF SMALL ANGULAR CONTACT BEARING AT HIGH SPEED

JOSEF KEKULA, JAN SMOLIK, MATEJ SULITKA
Keywords: ball bearings heat generation | high speed spindle | thermo-mechanical simulation of spindle | oil-air lubrication

In order to predict heat generation in super precision ball bearings at high speeds the Harris and Houpert frictional models were applied to a high speed range with maximum speed of 150 000 RPM. The measurement of thermal behaviour in super precision ball bearings was observed on a high speed spindle for micromilling. Outer ring bearing temperature and torque was measured simultaneously under stable lub (…)

RECYCLING OF AUTOMOTIVE SHREDDER RESIDUE BY GRANULOMETRIC SEPARATION

SIMONA SOBEKOVÁ – FOĽTOVÁ, TOMÁŠ HAVLIK, ANDREA MIŠKUFOVÁ
Keywords: end-of-life vehicle | light fraction | ASR | sieving | recycling | heavy metals

Recycling of end-of-life vehicles at shredder plants, among well-managed metal recycling, ends up with huge amounts of waste residue, for which the complex recycling route is still missing. Automotive shredder residue (ASR) is often called light fraction, because after the separation of all the metal particles (by magnetic drum, eddy-current, pneumatic separator and multiple unites of sieving) it contai (…)

IMPACT OF TOPOLOGY AND MAP PRECISION ON DESIGNED FLOW IN RAIN SEWERS

STEFAN STANKO, DUSAN RUSNAK, IVONA SKULTETYOVA, MICHAL HOLUBEC, KRISTINA GALBOVA
Keywords: sewer system | rain sewer | assessment | runoff coefficient | catchment

Sewer systems are undisputable part of environmental protection system. Design, construction and correct management of sewer systems eliminates or at least mitigates continual infiltration of sewage water to the environment and ground water. Verification of correct function of sewer system is done by the assessments. This study focuses on impact of terrain topology, placement and geometry of structures (…)

CAPILLARY VELOCITY OF NATURAL ZEOLITE POROUS CERAMIC IN DIFFERENT SINTERING TEMPERATURES

SRI MULYO BONDAN RESPATI, RUDY SOENOKO, YUDY SURYA IRAWAN, WAHYONO SUPRAPTO, WAHID BUDI SAPUTRA, HELMY PURWANTO
Keywords: ceramic | sintering | natural zeolite | porous | capillary

Lately, the membrane of porous ceramics begin to increase its utility since it contains good and supportive chemical substances, besides it is also resistant to heat and has stable force. However, its price is considered quite expensive because this type of ceramics is made from materials and is produced through complicated process. This study aims at utilizing the use of natural zeolite materials as th (…)