Modern Machinery (MM) Science Journal, March 2019

THE INFLUENCE OF RADIATION CROSS-LINKING ON MICRO-INDENTATION CREEP AND THE GEL CONTENT OF POLYAMIDE

Martin Ovsik, Martin Reznicek, Vojtech Senkerik, Michal Stanek, Lenka Hylova
Keywords: gel content | creep | micro-indentation | cross-linking | radiation | Polyamide 6.6

Radiation Cross-linking is a process, at which the control change of polymers carried out of the purpose to reach the new polymeric materials with modified properties occurs. The submitted study deals with the influence of radiation doses on micro-creep properties of filled on non-filled polyamide 6.6. Micro-indentation creeps of modified polyamide were measured using modern machinery DSI method (Depth- (…)

THE INFLUENCE OF THE NANO-FILLER FILLING AMOUNT ON CREEP PROPERTIES

Martin Reznicek, Martin Ovsik, Michal Stanek, Dagmar Merinska, Adam Dockal
Keywords: concentration | tensile – creep modulus | nano-material | creep | polyethylene

This article deals with the issue of the amount of clay type nano-fillers used for the improvement of mechanical properties of the basic material HDPE. These fillers already showed their positive influence on various mechanical properties. This article is primarily concentrated on the percentage of filling, which has a significant influence on these properties and also on the final product price in whic (…)

END MILLS WITH PCD INSERTS INCLUDING INTEGRAL CHIP BREAKER

Ales Polzer, Tomas Trcka
Keywords: EN AW 6082 | EN AW 6061 | force loading | chip breaker | PCD

Diamond – the chemically metastable form of carbon at room temperature and standard atmospheric pressure – has become the standard material used for cutting tools. Its specific cutting properties also correspond to its difficult machinability, making it one of the most difficult-to-machine materials. With regard to this, the optimal processing technology, sharpening parameters, soldering conditions as w (…)

METHOD OF NON-CONTACT MEASURING OF DIAMETER AND OVALITY OF STEEL TUBES DURING THEIR PRODUCTION

David Fojtik, Petr Podesva, Jan Gebauer, Jiri Czebe
Keywords: ovality | diameter | triangulation | 2D scanner | Laser scanning

The quality of production of metallurgical bar stock, in particular tubes, is assessed based on many production parameters including outer cross-section (diameter) and ovality, which are also specified by European standard EN 13 508. Tubes need to be measured as soon as possible, ideally immediately after the rolling mill during their production, so that any defects may be corrected in due time and thus (…)

DEVELOPMENT AND SPECIFICS OF THE CONSTRUCTION OF A LKMK 8000 LARGE CRANK PRESS

Milan Cechura, Martin Volejnicek
Keywords: optimization | forming force | die forging | forging press

The article deals with the development of large forging presses for die forging. It analyses individual aspects of the development of large presses. This is followed by market analysis and a search of design solutions by individual manufacturers. Set of design recommendations has been compiled from a variety of technical solutions, according to which a press that surpasses the competition can be properl (…)

FDM FOR HIGH TECH CERAMICS ON BASE THE ZIRCONIA IN APPLICATION OF DENTAL CROWNS

Daniel Sida, Vladimir Sida
Keywords: bio application | dental crown | ceramics | 3D printing | FDC | zirconia

Technical ceramics is worldwide known as advanced material for excellent properties like hardness, compression strength, corrosion resistance, electroresistance, as well some of them are unique for the biocompatibility, as well for a lot of applications able to use into the human body. One of the bottleneck usage such sophisticated materials are low knowledge of fabrication mainly part of the process t (…)

STUDY OF ABS AND SAN FAILURES UNDER DROP-WEIGHT IMPACT TEST

Tomas Fiala, Ales Mizera, Pavel Stoklasek, Miroslav Manas, Lenka Hylova, Martin Bednarik
Keywords: acrylonitrile butadiene styrene and styrene acrylonitrile | failure | drop-weight impact test | mechanical properties

Acrylonitrile butadiene styrene (ABS) is a tough material, which is used for engineering purposes (e.g. covers of electronic and engine parts). On the other hand, styrene acrylonitrile (SAN) is a brittle transparent material with good optical properties, it is used for household items, such as bowls and boxes in refrigerators. Both of these materials can be loaded by impact forces, for example, fall of (…)

DIGITIZATION OF HISTORICAL ARTWORKS FOR ARCHIVING PURPOSES AND REPRODUCTION WITH USE OF AVAILABLE REVERSE ENGINEERING METHODS

Jozef Dobransky, Jozef Torok, Peter Baron, Monika Teliskova, Jakub Kascak
Keywords: scanner | artwork | 3D digitization

Reverse engineering offers a wide range of application options for engineering production, but its techniques can also be applied while preserving cultural heritage. The following article highlights the possibilities of spatial digitization of a work of art using affordable means. Gradually describes the digitization process, point cloud processing, and the creation of output formats for the preservatio (…)

MACROSTRUCTURE DIGITALIZATION OF THE ROADWAY SURFACE PROFILES

Jakub Kascak, Petr Baron, Jozef Torok, Martin Pollak, Monika Teliskova
Keywords: watershed simulation | surface analysis | macrotexture | roadscan | 3D laser scanning

This paper considers the characteristics of the device ZScanner 700, its usage and ability to process data from measurements of the roadway’s geometric profile. It refers to the ability of ZScanner 700 to record surface deviations with sufficient accuracy and the possibility of processing obtained digitalized data in GOM inspect software for surface analysis and Global Mapper for watershed simulation. T (…)

MEASURING GEOMETRIC PARAMETERS OF PROXIMAL FEMUR BY USING REVERSE ENGINEERING

Nguyen Van Tuong
Keywords: CAD | reverse engineering | Vietnamese Patient | Proximal Femur | Total Hip

Today, total hip replacement surgery can be performed at many Vietnamese hospitals. However, all total hips in Vietnam are now imported from foreign countries. These hips are expensive and their designs do not accurately match with most Vietnamese patients. Designing total hips for Vietnamese patients is a demand at the moment. This paper presents a method to get some important geometrical parameters of (…)

CONSTRUCTIONAL MODIFICATION OF AN EXTRUSION DIE

Ludovit Kollath, Andrej Venger, Ernest Gondar, Miroslav Bosansky
Keywords: flow simulation | FEA | extrusion | die | extruder | WPC | composite | plastics | wood

The paper deals with the design and optimization of an extrusion die which consists of a die body and a set of replaceable plugs for various extrusion cross-sections. This system is primarily used for producing WPC products on the laboratory extruder EUROTECH EB30. The paper offers several designs of extrusion dies and examines their advantages as well as disadvantages. Based on this analysis, the best (…)

REPROCESSING OF STYRENE ACRYLONITRILE AND THE INFLUENCE OF THE PARTICLE SIZE ON TENSILE PROPERTIES

Vojtech Senkerik, Martin Ovsik, Martin Reznicek, Vaclav Janostik
Keywords: tensile properties | styrene acrylonitrile | particle size | sifting | Reprocessing

The purpose of this work is to determine the influence of the reprocessed polymer on tensile properties. Tested samples were obtained using the injection molding technology from the industrial unpolluted waste, which is the same material as the virgin styrene acrylonitrile (SAN). The waste was milled for further reprocessing and a mixture of different particles was obtained. This mixture was sifted to f (…)

NOISE EMISSIONS OF OLDER WOODWORKING MACHINES AT PARALLEL OPERATION PROCESS

Petr Junga, Petr Travnicek, Juraj Ruzbarsky, Zdenek Kopecky, Ales Solar
Keywords: woodworking machines | measurement of the noise | acoustic pressure | noise

The paper is focused on the evaluation of noise emissions of older woodworking machines in specific conditions of the individual and parallel operation process. The goal of the paper is monitoring of acoustic pressure of chosen woodworking machines (surfacer and thickenesser) in real woodworking industrial school plant. Next goal is a statistical evaluation of measured values and comparing with criteria (…)

COMPARISON OF THE POWDER BED FUSED MATERIALS FROM DIFFERENT POWDER MANUFACTURERS

Martina Koukolikova, Pavel Podany, Katerina Mertova
Keywords: Discrete Simulation | porosity | maraging steel | mechanical testing | powder size and distribution | Additive manufacturing (AM)

Additive manufacturing (AM) has enabled not only designers over the last few years to boost a huge boom in the design and optimization of machine components. Part of the additive manufacturing is not only the design of the component itself but the individual steps involved in the creation of computer documentation necessary for the preparation of the AM, the selection of suitable material and the printi (…)

EXPERIMENTAL SHRINKAGE STUDY OF CERAMIC DLP 3D PRINTED PARTS AFTER FIRING GREEN BODIES IN A KILN

Iaroslav Kovalenko, Yuvaraj Ramachandran, Maryna Garan
Keywords: photopolymer | debinding | SLA | DLP | 3D printing

The objective of this work was to investigate dimensional parameters of 3D printed parts from glass ceramic photopolymer before and after debinding and sintering in a kiln. During experiments batches of green bodies were printed with different layer thickness and curing strategy. We used 3D printer with ultraviolet LED as a light power source. The peak of intensity of the UV LED was in the range from 38 (…)

DESIGN OF DEDICATED AUTOMATED DEVICES WITH CAD SUPPORT

NAQIB DANESHJO, ZUZANA HAJDUOVA, ERIKA DUDAS - PAJERSKA, ENAYAT DANISHJOO
Keywords: production | component | structural 3D modelers | fixation | complex products | PLM systems | CAD systems | design

The thesis deals with the problem of fixing the flexible prism element to the supporting element which is the side contact pen. The resulting component will serve for the manufacture of wall-mounted switches or work panels. The aim of this work is the main design of the mechanical construction of the device which will be able to fix the elastic element on the complicated positioning of the tongue to mee (…)

INNOVATION OF ILIZAROV STABILIZATION DEVICE WITH THE DESIGN CHANGES

Filip Tomanec, Sona Rusnakova, Martina Kalova, Lukas Manas
Keywords: Kirschner | Ilizarov | tibia | glass-fiber composite | external fixator

An application of the osteosynthesis fixator as a surgical method for the large bone treatment has been deeply described during the last 70 years [Solomin 2012]. Even the design using composite material is available at the market. Nevertheless, the interconnection of the main requirements including lightweight, adequate stiffness and adjustability around the tibia bone is the next step in external fixat (…)

AN ACTIVELY CONTROLLED JOURNAL BEARING WITH INCREASED RESISTANCE TO INSTABILITY

Jiri Tuma, Jiri Simek, Miroslav Mahdal, Miroslav Pawlenka, Vaclav Pavelka
Keywords: machining process | proximity probes | active vibration control | piezo-actuators | non-rotating loose bushing | journal bearings

Journal hydrodynamic bearings are used for their high radial load capacity and operation at high speeds. The only disadvantage is the excitation of vibrations, called an oil whirl, after crossing a threshold of the rotational speed. The whirl can be suppressed using the controlled motion of the non-rotating loose bushing which is actuated by piezo-actuators. The displacement of the piezo-actuators is go (…)

SEVERITY INDEX FOR VEHICLE DRIVERS AT FRONTAL IMPACT INTO RIGID BARRIER

Jozef Kmec, Stella Hrehova
Keywords: severity index (SI index) | active and passive safety | Deformation path

This article deals mainly with frontal impacts of vehicles of various classes (small cars, middle class, Pickups/SUVs, etc.) into a fixed barrier according to the NHTC (National Car Traffic Safety Administration) for the US-NCAP (New Car Assessment Program). The acceleration record was processed from the accelerometer through the Logger Pro program package. If the accelerometer was firmly connected from (…)

INFLUENCE OF BASIC PROCESS PARAMETERS ON MECHANICAL AND INTERNAL PROPERTIES OF 316L STEEL IN SLM PROCESS FOR RENISHAW AM400

Jiri Hajnys, Marek Pagac, Ondrej Kotera, Jana Petru, Sebastian Scholz
Keywords: porosity | additive manufacturing | SLM | mechanical properties | Process Parameters

The paper deals with the study and experimental evaluation of the influence of process parameters determining the resulting mechanical properties of the components after additive production using the 1.4404 (316L) stainless steel SLM method. The determining process parameters that have been investigated are laser power, scanning speed and layer creation strategy. These parameters fundamentally affect th (…)

INFLUENCE OF THE MATERIAL ON THE ACCURACY OF OPTICAL 3D DIGITALISATION

Radomir Mendricky, Ondrej Langer
Keywords: Digitalisation | Material Effect | Contactless 3D Scanners | Fringe projection sensor | Optical 3D Digitalisation

In recent years, optical digitalization is increasingly being used for the inspection of the dimensional qualities of parts. Different products from various materials used in 3D printers are scanned - metal, plastic, composite or special materials. The surface may be of a different color or roughness, may be glossy or matte. Practice suggests that the surface properties of the scanned part can significa (…)

SET OF GEOMETRIC ERRORS EVALUATION BASED ON R-TEST MEASUREMENT

Martin Moravek, Otakar Horejs, Pavel Bach
Keywords: R-test | Machine tool | volumetric error | geometric error | accuracy

Presented paper deals with the development of a procedure for fast measurement and evaluation of the set of basic geometric errors of the five-axis milling machines. Based on R-test measurement a rotary axes pivot point position and orientation errors and linear axes squareness errors are evaluated. The developed procedure is experimentally verified on a five-axis milling machine. Using the kinematic mo (…)

MOLD DESIGN FOR RINGS OF EXTERNAL FIXATOR

Martina Kalova, Filip Tomanec, Sona Rusnakova, Lukas Manas, Zdenek Jonsta
Keywords: aluminium mold | prepreg compression molding | mold design | external fixator | Composite ring

This paper deals with a structural design of a mold for making a composite ring of external circular fixator used in medical applications. It also focuses on the choice of technology and material for the production of a fixator ring. Due to the high demands on the quality, appearance, material of the product and higher series production, prepreg compression molding was chosen for this purpose. Thanks t (…)

PROCESSING OF OPERATING DEFLECTION SHAPES

Pavel Suranek, Jiri Czebe, Vaclav Pavelka, Renata Wagnerova
Keywords: Transfer function | Matlab | frequency transfer function | deflection shapes | cross-spectrum | Auto-spectrum

The article deals with measurement and visualization of the operating deflection shapes (ODS) on laboratory task. The aim is to measure the Frequency Response Function (FRF) of selected points of the template. Together with the visualization of their magnitude, real part, imaginary part or phase, and show template‘s ODS. The measuring chain consists of an accelerometer, laser, and shaker. Data acquisiti (…)

MECHANICAL PROPERTIES OF BIODEGRADABLE PLA PLASTIC PARTS PRODUCED BY 3D PRINTING

Juraj Beniak, Peter Krizan, Milos Matus
Keywords: measurement | rapid prototyping | tensile strength | PLA plastic | 3D printing | additive manufacturing

The presented paper is focused on FDM (Fused Deposition Modeling) 3D printing technology, which works with thermoplastic materials that are gradually applied layer by layer to the work platform. As we know, plastics are made from crude oil, and in general, they are an environmental burden on our environment. However, there are also different plastics that are produced from renewable sources and are envi (…)