Modern Machinery (MM) Science Journal, October 2015

VOLUMETRIC COMPENSATION OF THREE-AXIS VERTICAL MACHINING CENTRE

MICHAL HOLUB, PETR BLECHA, FRANTISEK BRADAC, ROMAN KANA
Keywords: ballbar | LaserTRACER | Machine tool | volumetric accuracy | volumetric compensation

This contribution assesses the possibilities of application of volumetric compensation technology on a small three-axis vertical machining centre. These machine tools are designed for machining of small workpieces with various requirements on dimensional and shape accuracy. Small machine tools do not show large volumetric deviations across the entire working space as it is seen with medium-sized and lar (…)

HYBRID BODY OF UNDERGROUND RAILWAY CAR: PATH TOWARDS REDUCED WEIGHT OF RAIL VEHICLES

PETR HELLER, JIRI KORINEK, LADISLAV TRISKA
Keywords: composite materials | weight savings | rail vehicles | hybrid body | underground railway

The purpose of the development of a hybrid body for underground railway cars was to achieve weight reduction and a favourable impact on operating costs, primarily due to energy savings. The present paper describes the construction sequence of a prototype body shell.

BASIC ALGORITHMS OF INPUT SHAPING AUTOTUNING

MACIEJ GNIADEK, STEFAN BROCK
Keywords: two-mass system | autotuning | command generation | input shaping

Many mechanical systems contains flexible joints. The main problem in control of these kinds of objects are oscillations. The control strategy can be supplied by signal shaping methods. One of the simplest and most effective algorithm of reference signal shaping is named input shaping. The problem of input shaping tuning can be automatized. The paper shows two basic algorithms of input shaping autotunin (…)

EXPERIMENTAL OBSERVATION OF ELASTOHYDRODYNAMICALLY LUBRICATED CONTACTS REPLENISHMENT

DAVID KOSTAL, PETR SPERKA, PETR SVOBODA, IVAN KRUPKA, MARTIN HARTL
Keywords: composite materials | weight savings | rail vehicles | hybrid body | underground railway

Starved regime of elastohydrodynamic lubrication (EHL) is usually described by smaller thicknesses of the lubrication film then fully flooded regime. This state can be caused by a number of reasons including operating conditions, lubricant supply or/and its properties. Rolling bearings contain multiple consequent elements which can increase the risk of starvation because the replenishment mechanisms are (…)

VIRTUAL REALITY BASED DESIGN AND CALCULATION TOOL FOR IMPROVING DYNAMICS OF MACHINE TOOLS

VOLKER WITTSTOCK, MARTIN KOLOUCH, JAN BERTHOLD, MARKUS RICHTER
Keywords: structural dynamic modification | Machine tool | design visualization | design optimization | Virtual Reality

This paper presents an extended workflow to improve the dynamic behaviour of machine tools that is fully controlled in the virtual reality environment (VR). The workflow utilizes a common platform for the visualization of results of an experimental modal analysis and the following structural dynamic modification to eliminate the weak points of the design. Based on the overlaid visualization of measured (…)

IMPACT OF MICROCLIMATE CONDITIONS ON THE CONTROL ROOM PERSONNEL - CASE STUDY

LUBOS KOTEK, PETR TRAVNICEK, FRANTISEK BABINEC, PETR JUNGA, LEISAN MUKHAMETZIANOVA
Keywords: carbon dioxide | humidity | temperature | work environment | control room | reliability of human factor | Ergonomics

The present contribution deals with the influence of work environment factors on the control room personnel, in particular the temperature and humidity parameters, and concentration of CO2. This contribution summarizes selected practical experience of implementing ergonomic analysis and evaluation of the impact of these parameters on the reliability of human factor in the chemical industry, power engine (…)

SAFETY CULTURE AND AGILE

VERA PELANTOVA, JANA VITVAROVA
Keywords: Scrum | agile team | organisation management system | safety aspect | safety culture | agile methods

Agile methods, a perspective alternative to the traditional project management, extend across organisations gradually. Their introduction is, however, confronted with safety aspects which are an integral part of activities in each organisation. This article deals with the relation between agile methods and the safety culture of an organisation using a comparative study based on authors’ research perform (…)

TOPOLOGY OPTIMIZATION OF A BICYCLE PART

PETR ZELENY, MILOS CADEK
Keywords: MTB | FEA | SLM | 3D printing | topology optimization

The paper contains suitable methodics to obtain optimal part design due to operational (static) load cases. The subject of optimization is an upper rocker of a special mountain bike frame. To obtain optimized part design a topology optimization method combined with a numerical shape optimization was used. Optimized part was manufactured by Selective Laser Melting technology. The paper begins with introd (…)

MODERN METHODS FOR MANUFACTURING PLANNING AND SCHEDULING

IVANA SIMEONOVOVA, ALEKSANDAR GYUROV, SIMEON SIMEONOV
Keywords: composite materials | weight savings | rail vehicles | hybrid body | underground railway

The paper deals with modern methods which can be used for planning and scheduling of manufacturing systems. Creating of production plans, using different software products is discussed. Advanced planning and scheduling methods are used for planning and scheduling. The outputs as Gantt charts are presented. Different optimization methods are applied for schedule optimization. Production plan, for every m (…)

MAINTENANCE MANAGEMENT SYSTEM

HANA PACAIOVA, JURAJ GLATZ
Keywords: KPI | FMEA | RCM | TPM | risk management

Maintenance Management requires acceptance of basic systems approach, i.e. implementation of company goals to management goals. Well know Maintenance management philosophies (TPM, RCM, RBI) applied in order to improve processes, often remain only on the basis of the implementation of services without the need for full integration into existing management systems. Misunderstanding the nature of maintenan (…)

PARAMETERS INFLUENCING THE PRECISION OF SLM PRODUCTION

PETR KELLER, RADOMIR MENDRICKY
Keywords: 3D digitization | 3D optical scanner | geometrical accuracy | selective laser melting | SLM

This article focuses on production of parts by Selective Laser Melting (SLM) technology, where the prototype part is created by melting metallic powder in selective manner by means of laser – layer by layer. Due to the laser, the model is loaded with high temperatures – the high-temperature stress in the material occurs during the production and consequent cooling, resulting in undesired deformation of (…)

ANALYSIS OF MEASUREMENT ACCURACY OF CONTACTLESS 3D OPTICAL SCANNERS

RADOMIR MENDRICKY
Keywords: accuracy | 3D digitization | 3D optical scanner | laser scanner | optical measurement

Currently, the conventional measuring methods in industry are more and more substituted with new methods, where the inspected component is firstly digitised by means of so called optical 3D scanners, and the inspection of dimension and shape precision is performed on the obtained virtual model. This approach bears many advantages and, in many cases, provides faster and more objective results. On the oth (…)

PARALLELS BETWEEN CORPORATE SOCIAL RESPONSIBILITY AND THE EFQM EXCELLENCE MODEL

HELENA CIERNA, ERIKA SUJOVA
Keywords: environment | ethics | business | EFQM excellence model | corporate social responsibility

CSR is a continued promise by companies to act ethically, to contribute to sustainable economic development, and to contribute to improvement of quality of life of its employees, their families, as well as local communities and society as a whole. Increasing demands on productivity and effectivity of business subjects rightfully result in efforts to implement better management systems, which take into c (…)

ENVIRONMENTAL REPORTING IN THE ENTERPRISE AND RELATED ISSUES

MIROSLAVA POLANKOVA, FRANTISEK MANLIG, RUZENA KRALIKOVA
Keywords: management | ecological | audit | accounting | environment

The article deals with environmental reporting in the company. The environmental reporting, new trends and its benefits are describes. Environmental reporting can actively monitor, manage and gradually reduce the negative impact of companies activities on the environment. The other concepts that are closely related to reporting are also describes in the article. It's environmental communication and audi (…)

IMPLEMENTATION OF COLD ROLLING PROCESS IN BEARING INDUSTRY

JAN OTOUPALIK, ZUZANA FISEROVA, MIROSLAV NESLUSAN, KAMIL KOLARIK
Keywords: Structure | residual stresses | cold rolling | bearing

This paper deals with implementation of various strategies in production of bearings and their influence on the consecutive operations. Shaping of bearings via cold rolling in compared with conventional process usually employed in bearing industry based on machining cycles on hot rolled parts. Such aspects as structure, stress state before and after heat treatment, rings deformations after heat treatmen (…)

DETERMINATION OF THE GRAIN GROWTH KINETICS AS A BASE PARAMETER FOR NUMERICAL SIMULATION DEMAND

JAROMIR MORAVEC
Keywords: Gleeble | Welding | 18Cr9Ni3CuNbN steel | X10CrWMoVNb9-2 steel | numerical simulation | grain size

The grain size is an important parameter influencing not only the material brittleness and strength properties, but also the transformation processes of creep, strength, and fatigue. This present paper is therefore focused on the process description for the experimental determination of the kinetics of grain growth curves temperature dependence. These curves are then used for numerical simulations of gr (…)

DEVELOPMENT OF CUSTOMER LOYALTY MEASUREMENT AT CZECH COMPANIES

JAROSLAV NENADAL
Keywords: organization´s performance | customer retention | measurement | feedback | customer loyalty | quality management system

Any efficient quality management system must use permanent feedback from customers. All organizations certified against the ISO 9001 standard should measure customer satisfaction. At present, such feedback seems to be unsufficient. A customer loyalty or value for customer represent advanced values for modern organizations. Unfortunately, these values are underestimated or completely ignored at Czech org (…)

COMPARISON OF TAGUCHI'S PARTIAL CORRECTION TECHNIQUE WITH CONTROL CHARTS

LUBOS KOTEK, ALES NOSEK, ALOIS FIALA, JIRI ZAHALKA
Keywords: Beta correction | hole reaming | Taguchi's partial correction | control charts | statistical process control

This article compares the most commonly used methods of statistical quality control (control charts - in our case the control chart of individual values) with the Taguchi’s method of Partial Correction. The comparison applies to an actual process of hole reaming, and a test is carried out of gradual change of setting (continuously increasing simulation deviation).