Analysis of eccentric press shaft of fatigue fractures

The paper presents selected eccentric press stress analysis aspects. This approach is based on the assumption that fractures can be present in the analyzed constructions. Calculations define the current state of the component in view of fracture mechanics. Calculations were performed using analytical, numerical and experimental methods for construction element durability assessment

Virtual testing in terms of pedestrian safety improvements

Pedestrian fatalities in traffic accidents continue to be a significant social burden and pose a costly hospitalization problem. Statistical research conducted in European countries onfirms that pedestrians account for 12-35% of severely injured or illed victims of road traffic accidents. The paper outlines the European test procedure and a pedestrian safety guideline drawn up by the EEVC (European Enhanced Vehicle-Safety Committee). In addition, the emphasis is put on the Virtual Testing regarding the current regulations. The great development of computation power and expansion of Finite Element Method enables to widen the possibilities and application fields including pedestrian safety in terms of a collision with the front of a motor vehicle

Child safety on various bicycle-mounted seats during vehicle impact

This research addresses an important gap in the state of the art by investigating the safety of vulnerable road users – children transported on bicycle seats. The article focuses on three forms of bicycle-mounted child seats and their kinematics during an accident scenario involving a motor vehicle. The front, rear-frame and rear-rack mounted child seat mounting configurations were considered in this study. The research covers the impact of a sports sedan vehicle against a bicycle equipped with the child seat. The assessment of the child safety was done through numerical simulations by coupling the codes of MADYMO and LS-DYNA. The after-impact kinematics for various baby carriers is presented with the emphasis on child’s head and neck injuries. The results were compared to the full-scale test available in the literature. The findings prove a low protection level for the child provided by the bicycle carriers in all considered cases. The study is further devoted to directions of increasing child safety in this means of transportation. First published online 18 March 201

Porównanie postaci konstrukcyjnych koła zabierakowego pojazdów koparki wielonaczyniowej

Tyt. z nagłówka.Bibliogr. s. [238].Dostępny również w formie drukowanej.STRESZCZENIE: Zabieraki pojazdów gąsienicowych maszyn podstawowych górnictwa odkrywkowego są elementami bardzo obciążonymi, poddanymi silnemu ścieraniu i wymagającymi częstej wymiany wskutek zużycia. Koło zabierakowe powinno umożliwić taką wymianę, a ponadto spełniać określone wymagania wytrzymałościowe. Przedstawiono trzy wersje koła napędowego gąsienicowego mechanizmu jazdy koparki wielonaczyniowej. Pokazano postacie geometryczne rozwiązań konstrukcyjnych. Omówiono sposób identyfikacji warunków brzegowych. Na podstawie przeprowadzonych obliczeń metodą elementów skończonych szczegółowo opisano wady i zalety zaproponowanych wersji. SŁOWA KLUCZOWE: koło zabierakowe, maszyny podstawowe górnictwa odkrywkowego, metoda elementów skończonych, analiza wytrzymałościowa. ABSTRACT: Driving centres of surface mining crawlers are high loaded elements. These elements are also strongly abraded. Therefore the mining machine requires frequent replacement of the wearied elements. Driving centre should allow for such replacement, and also meet certain strength requirements. Three versions of the wheel drive mechanism of the Bucket Wheel Excavator have been presented. Geometric forms of various construction solutions have been also shown in the paper. Apart from this, boundary conditions have been identified to carry out the numerical analysis with the use of FEM. Finally, advantages and disadvantages of proposed solutions have been presented. KEYWORDS: caterpillar wheel, surface mining machines, finite elements method, strength analysis

Wybrane zagadnienia modernizacji połączenia wału koła czerpakowego z przekładnią planetarną

Tyt. z nagłówka.Bibliografia s. 542.Dostępny również w formie drukowanej.STRESZCZENIE: Połączenia dociskowe stosowane w mechanizmach urabiania koparek wielonaczyniowych kołowych w wielu przypadkach są źródłem poważnych problemów remontowych i strat finansowych. W przypadku maszyn urabiających wyjątkowo trudnourabialne utwory w KWB "Turów" najważniejszym mankamentem zastosowanych w nich połączeń dociskowych jest tendencja do powstawania połączeń adhezyjnych na powierzchni docisku rurowej części jarzma do czopa wału koła czerpakowego. Ściągnięcie przekładni z wału każdorazowo skutkuje uszkodzeniami powierzchni wału lub jest niemożliwe bez zniszczenia wału. Generalnie po demontażu wał i jarzmo wymagają regeneracji lub wymiany. Jest to jeden z głównych powodów, z których wszczęto projekt zmierzający do opracowania nowego rozwiązania. W artykule przedstawiono wybrane zagadnienia konstruowania nowego połączenia jarzma przekładni planetarnej z wałem koła czerpakowego. W wybranym rozwiązaniu połączenia kształtowego wykorzystywane są w maksymalnym stopniu istniejące elementy mechanizmu urabiania. Wszystkie opracowane rozwiązania konstrukcyjne poddano wnikliwej analizie wytrzymałościowej MES z uwzględnieniem sposobu wykonania. SŁOWA KLUCZOWE: Układy napędowe koła czerpakowego, połączenia dociskowe, połączenia kształtowe. ABSTRACT: Clamp joints used in the mining mechanisms of multibucket wheel excavators are the cause of serious repairing problems as well as financial looses. As far as the mining machines of quite difficult to mine formations in KWB Turów are concerned, the most important deficiency of used in these machines clamp joint is a tendency to form the adhesion connection on the surface of clamp of the movable part of yoke to the pin of the buckle wheel shall. Every time pulling down the gear from the shaft causes the shaft surface defect or is not possible to do without damage. Generally after disassembling, shaft and yoke need to be regenerated or exchanged. This is the one of the main reasons, that the project concerning the elaboration of new solution was started from. In the article, the chosen issues of designing the new connection between planetary gear yoke and bucket wheel were presented. In the chosen concept of shaped joint the existing elements of mining mechanism are maximally used. All of the elaborated structural solutions underwent the penetrating strength FEM analysis with taking the way of performing into consideration. KEYWORDS: Bucket wheel drive systems, clamp joint, forming joint

13th International Conference on Computer Aided Engineering

These proceedings of the 13th International Conference on Computer Aided Engineering present selected papers from the event, which was held in Polanica Zdrój, Poland, from June 22 to 25, 2016. The contributions are organized according to thematic sections on the design and manufacture of machines and technical systems; durability prediction; repairs and retrofitting of power equipment; strength and thermodynamic analyses for power equipment; design and calculation of various types of load-carrying structures; numerical methods for dimensioning materials handling; and long-distance transport equipment. The conference and its proceedings offer a major interdisciplinary forum for researchers and engineers to present the most innovative studies and advances in this dynamic field

Method of operator safety assessment for underground mobile mining equipment

The paper presents a method of assessing the safety of operators of mobile mining equipment (MME), which is adapted to current and future geological and mining conditions. The authors focused on underground mines, with special consideration of copper mines (KGHM). As extraction reaches into deeper layers of the deposit it can activate natural hazards, which, thus far, have been considered unusual and whose range and intensity are different depending on the field of operation. One of the main hazards that affect work safety and can become the main barrier in the exploitation of deposits at greater depths is climate threat. The authors have analysed the phenomena which may impact the safety of MME operators, with consideration of accidents that have not yet been studied and are not covered by the current safety standards for this group of miners. An attempt was made to develop a method for assessing the safety of MME operators, which takes into account the mentioned natural hazards and which is adapted to current and future environmental conditions in underground mines

Proactive Condition Monitoring of Low-Speed Machines

This book broadens readers’ understanding of proactive condition monitoring of low-speed machines in heavy industries. It focuses on why low-speed machines are different than others and how maintenance of these machines should be implemented with particular attention. The authors explain the best available monitoring techniques for various equipment and the principle of how to get proactive information from each technique. They further put forward possible strategies for application of FEM for detection of faults and technical assessment of machinery. Implementation phases are described and industrial case-studies of proactive condition monitoring are included. Proactive Condition Monitoring of Low-Speed Machines is an essential resource for engineers and technical managers across a range of industries as well as design engineers working in industrial product development. This book also: ·         Explains the practice of proactive condition monitoring and illustrates implementation phases ·         Presents detailed discussion of best techniques for proactive condition monitoring specifically for low-speed machines ·         Demonstrates application of finite element modeling for successful proactive condition monitoring ·         Broadens readers’ contextual understanding with case-studies related to applications of proactive condition monitoring in heavy industr

Estimating the Remaining Operating Time of Mining Headframe with Consideration of Its Current Technical Condition

AbstractThe condition of headframes in underground mines has a substantial effect on the proper operation and safety of hoisting equipment. One of the potential problems that might occur during operation is the tilting of these structures, which can lead to difficulties in operation and, in extreme cases, to failures. The paper presents an original method of evaluating the technical condition of headframes, estimating the remaining operating time and finding the causes of irregularities in the operation of this kind of structures. To show this, a series of experimental studies and structural analyses were conducted on a model headframe. Based on experimental tests and numerical calculations, the operational safety of the structure was established along with limit values of operational parameters and possible preventative measures were proposed