Browse

21 - 30 of 122 items :

  • Materials Sciences, other x
  • Business Management x
  • Materials Sciences x
  • Process Engineering and Industrial Engineering x
Clear All
Safe choice of structural steels in a region of ultra-high number of load cycles

Abstract

In this paper the authors introduce their own selected experimental results in the field of the investigation of fatigue resistance of structural steels. The experiments were carried out on the nine structural steels including high strength steels, DOMEX 700MC, HARDOX 400, HARDOX 450, 100Cr6 (UTS from 446 MPa to 2462 MPa) at high-frequency cyclic loading (f = 20 kHz, T = 20 ± 5 °C, R = -1) in the region of number cycles ranged from N ≈ 2×106 to N ≈ 2×109 cycles of loading. The continuous decrease of fatigue strength in dependence on the number of loading cycles was observed with the average value of ratio σa2×109/σa2×106 = 0.69.

Open access
The use of quality management techniques to analyse the cluster of porosities on the turbine outlet nozzle

Abstract

As part of continuous quality improvement in well-managed enterprises, identifying unconformity should initiate actions to find their causes. Therefore, it was proposed to the enterprise located in Podkarpacie to use in the sequential way the Ishikawa diagram and 5Why method. The aim was to analyse of unconformity (porosity cluster) on the turbine outlet nozzle and identify the root of its creation. In the enterprise, the quality analysis of the products with a fluorescent method was carried out, but after identifying the unconformity, non-analysis of their reason for their occurrence was not practiced. Therefore, it was intentional to propose the use of sequence i.e. Ishikawa diagram and 5Why method to identify the root of unconformity. The subject of study was the turbine outlet nozzle, on which the fluorescent method the porosity cluster was identified. With the use of the Ishikawa diagram, the main cause of the problem was pointed (unconformity during production), and by the 5Why method the root cause of the problem, i.e. unconformity material from the supplier, was identified. The proposed method sequence is a simple and effective way to make analyses of unconformities and it can be used in different products and service enterprises.

Open access
Analysis of the implementation of the identification system for directly marked parts - DataMatrix code

Abstract

A photocode in Polish is a common name for a two-dimensional code, which is characterized by higher information capacity than a traditional barcode. The paper analyses the use of the two-dimensional coding system - DataMatrix to identify and classify the material stream in the production process. The analysis showed the effectiveness of the implementation of the coding system in the context of increased availability, machine use and increased product quality. The improvement in the production process is confirmed by an increase in the OEE index. As part of further improvement measures, the coding system should be implemented throughout the enterprise, its compatibility with existing systems should be ensured and applied to all products.

Open access
The delocalization of production to Poland

Abstract

This paper presents some aspects of the process of services, products and manufacturing transfer, with the associated production resources, from other locations and plants to Poland.

The study was carried out on the basis of an analysis of publications about delocalization as well as by means of desk research, where there were used the accessible primary and secondary data such as branch reports, statistical data available in reports, data bases, and information accessible on Polish and European websites. The article is also the result of the author's experience of participation in the relocation of a number of international companies, regarding various industries. Delocalization in Poland was presented both from the point of view of Conceptualizing delocalization (literature review, theoretical position) and Implementation of production.

The delocalization mainly takes advantage of labor forces. On the other hand, it may also concern innovative activities and develop high-tech for regions affected by economic restructuring. The social policies for the risk mitigation of the delocalization of production are also being developed and implemented. This work clarifying the conditions of delocalization in Poland and highlight the important roles played by innovation and institutions for achieving sustainability.

Open access
Electric aircraft - present and future

Abstract

In this paper, an outlook about the present of electrical aviation is given. The relatively small energy density of current battery technologies is adequate to build usable electric car, but not suitable for electric aircraft. Because of the very limited amount of energy available on-board, a couple of percent in efficiency can give significant increase in range and flight time, hence the development of more efficient propulsion system and E-motor is as important as the development of battery technologies. Current research results at the University of Dunaujvaros show, that building E-motors from amorphous materials is possible, and can easily increase the efficiency of high speed E-motors.

Open access
The impact of composition dependent and process-related properties in the laser cutting of metallic glassy tapes

Abstract

A short survey is reported on the advantageous and disadvantageous properties of soft magnetic glassy tapes to build stator and rotor elements for the increase of motor efficiency. The relative high saturation magnetization and the relative permeability of these alloy groups seem to be promising in this application field. On the other hand, the sample thickness (30 µm) displays limitations in terms of a filling factor. High hardness of tapes hinders the effectivity of mechanical shaping. Laser cutting can be successful as shaping method, presuming that the extension (thickness) of heat affected zone (HAZ) can be successfully reduced below 50µm, avoiding the brittleness evolution.

Open access
Implementation of Six Sigma methodology using DMAIC to achieve processes improvement in railway transport

Abstract

The provision of quality transport services is a prerequisite for the creation of an efficient organization that can meet the expectations and requirements of both the enterprise itself and its customers. From the railway enterprise's point of view, it is necessary to pay attention to the increasingly demanding requirements of its customers in railway passenger transport. This article focuses on identifying defects in rail transport processes that negatively affect ordinary operations. One of the most serious bottlenecks affecting railway transport reliability is the train delay, which fundamentally affects the perception of railway transport. At the same time, it emphasizes the need to apply individual tools according to the DMAIC cycle in order to achieve continuous improvement. The aim of the implemented Six Sigma methodology in railway enterprise is disciplined application of statistical problem-solving tools to recognize the gaps in the transport process and set out individual steps for their gradual removal.

Open access
Mechanical and mathematical research of local deformations of a steel roller shell with a variable geometry of contact surface

Abstract

The article is devoted to solving the fundamental and applied problem of nonlinear structural mechanics of machines by introducing into the drum two additional stop cylinders with supporting rollers at the end and adjustable length, providing a given elliptical or circular shape of a flexible shell with a smoothly variable geometry in the area of its contact with compacted pavement material. Compaction of soil, gravel and asphalt concrete in the sphere of road is not only an integral part of the technological process of the roadbed, road foundation and surface construction, but it is actually the main operation to ensure their strength, stability and durability. The quality, cost and speed of road construction, the possibility of using fundamentally new technologies, structures and materials is largely determined by the availability of modern road machinery.

Open access
Multi-criteria decision analysis for simplified evaluation of clean energy technologies

Abstract

Technology assessment (TA) is not a new concept. High value energy technology identification needs to be followed by a decision process in which all shareholders contribute. A case study on Combined and Heat Power (CHP) technologies considered is presented to illustrate the applicability of fuzzy analytical hierarchy assessment approach (FAHP). The goal of this paper is to identify and evaluate the best variant of CHP technologies using multi-criteria that are technical feasibly and cost effective reflecting performance parameters. The results depict that technology A2 with an overall ranking of 0.438 is the best alternative compared to others. Taking into consideration decision parameters for the section, A1 is found to be relatively most important with a rating of 0.434 with its reliability and cost effectiveness. The presented fuzzy-based methodology is general expected to be used by a diverse target groups in energy sectors.

Open access
Problems of use of FMEA method in industrial enterprise

Abstract

Presented paper concentrate on problems connected with FMEA method usage in industrial enterprise. There is in the paper a description of the basic rules of FMEA method and competition between FMEA analysis and gap analysis. The analysis of defects has been done to find recommendations how to eliminate or restrain them. On the basis of conducted research we found that selection of staff to the team is very important factor in the FMEA analysis undertaking process. The staff should have appropriate level of knowledge about FMEA method methodology and other tools which are indispensable in the process of implementing this method within the company.

Open access