Applied Mechanics and Materials Vol. 616

Abstract: The paper deals with an experimental analysis of a technological head tilt angle impact to vibration generation. The search of the technological head tilt influence is performed for three technological head shift speeds and for three abrasive water medium pressure values. From graphic records showing relation of vibration acceleration amplitude to its frequency, a group of 9 comparative frequency envelope graphs for two tilt angles and three technological medium analyzed pressures for each of three speeds of the head shift is created. On the base of the frequency envelope comparative graphs a discussion and formulated conclusion are stated. The paper presents a thematically integrated part of the thesis and complements recent knowledge on water jet technology manufacturing system working condition diagnosis.

Abstract: This paper aims to present completely new method of processing experiments which leads to obtaining input data for numerical simulations of heat treatment of large scale parts. Owing to stated method it will be possible, by using experiments on small tested sample, to simulate cooling conditions comparable with cooling of large scale parts. Apart from that this method of testing makes current boundary conditions during real cooling process more accurate, but it also multiplies stated conditions e. g. by effect of movement of cooling part in hardening media. In the paper we will also present the experimentally obtained difference in cooling rates measured by normalized quench test, standard way of hardening and a method according to newly suggested methodology.

Abstract: The thesis deals with a manufacturing system water jet technological head tilt angle influence analysis. The search is performed for two tilt angles and three speeds of the technological head shift. Frequency envelope comparative graphs are created for the head tilt angles 45o and 90o and for each of three speeds using graphical records which show vibration acceleration amplitude relation to its frequency. For each of the tilt angles summary comparative frequency envelope graphs in all analyzed speeds are created, too. On the base of the comparative frequency envelope graphs a discussion focused on results and formulated conclusion are performed. The paper presents a thematically integrated part of previous research and complements recent knowledge on technological and material parameter impact to water jet technology manufacturing system vibration generation.

Abstract: The Water as an element with its force is applied to the solid substances and thus violates their. A man started to notice the power of water and gradually it began to exploit to their advantage and developed technology of machining of various materials, which brought a facility generating pressure water jet. [1] Presently cutting materials technology is an essential technology pre-production stages. Article discusses the production system with technology of abrasive water jet and is aimed at assessing the impact of selected factors of the technological process in the dividing of materials using this technology. The main part describes the influence of factors on the depth of cut and surface topography of machined in terms of roughness. At the end of the article are evaluated selected technological factors used in cutting of materials.

Abstract: The main effort of each technological process is not only to reduce the costs, but also to reduce the impact on the environment. The technology of abrasive water jet is one of the methods of division and cutting materials with the lowest impact on the environment, since water is the cutting tool, in our case with the addition of an abrasive. The aim of the measurement was the observation (examination) and evaluation of the vibration impact on the technological head in the technology of abrasive water jet when changing the selected technological parameters, namely the feed rate of the technological head. The experiments were carried out on one kind of material - steel HARDOX 500 with a thickness of 10 mm. The impact of the change of the technological head’s feed rate (100, 50, mm/min) on the size of the vibration acceleration amplitude and its frequency were examined. A database was created from the measured vibration values on the technological head and from that database the data was evaluated in selected softwares (LabVIEW, SignalExpress a Microsoft Excel). Graphical dependencies, frequency spectra covers and covers comparison graph were created from which new findings and conclusions were formulated.

Abstract: High speed bearings are specified with mechanical properties, technological parameters and defined microstructure too. When these qualities are not respected in the manufacture, arise significant damage and consequently their not running ability. Cause of damage can also be bad operating conditions during its operation running. In this work microstructure characteristics are evaluated due to significant damage of the high speed bearings and thus its rejection of traffic. After microstructure investigation was not changed this microstructure but in some places micro hardness value was below the limit value, which is given by the producer and it was a consequence of bearing damage.

Abstract: Present article deals with assessing the influence of moisture content in thermoplastic material on rheological properties of material. The measurements were carried out on samples of hygroscopic plastics, i.e. plastics that tend to absorb moisture from the surrounding environment. Moisture in plastic material before its processing can have negative influence on physical or thermal properties of a product and can devalue visual aspect of the end product, thus these plastics have to be dried before their processing. Observed samples of materials were placed in three different rooms and measurements of Melt Volume-Flow Rate of thermoplastics were carried out at precisely determined intervals. Moisture content in material was determined by Mettler Toledo HB43-S moisture analyzer. To determine the influence of moisture content on rheological properties of material, a method of determination of Melt Volume-Flow Rate (MVR) of thermoplastics was used. The measurements were performed by using Termo Haake Meltflow MT etxrusion plastometer.

Abstract: The paper deals with an experimental assessment of the dynamics of gears. The experi- mental station for dynamic tests of gears is described and methodic for assessing their dynamic characteristics is chosen. There are listed results of the dynamic analysis of worm gear boxes made to verify the correct function of the test station and the appropriateness of the chosen methodic for measurement of assessed parameters.

Abstract: The article deals with the diagnostics of components surface after painting by camera system in real-time. This solution is especially suitable for implementation to automatized production line above the conveyor belt. The faults on the part surface can be detected as scratches, imperfect surface coverage and dirt stuck to the surface. The scratch detection is based on edge detectors, imperfect coverage are checked by histogram comparison and all other errors are detected by counter detectors. The developed software uses open source library OpenCV and is written in C++ language. The software solution is platform independent. Final algorithm is implemented to embedded device based on SoC.

Abstract: Purpose of this paper is to compare the characteristics of cutting of materials of different structures for testing intermittent cutting. Materials comparisons in the machining of steel strips samples C45 (12 050) are: cutting ceramics and cemented carbides. These materials have different characteristics of the cutting properties. Intensive development in the form of improved cutting properties passed in recent year’s just cutting ceramics. This is what resulted in its use not only for machining a continuous section, but its application was extended to the intermittent cutting machining.