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Artykuł skupia się na unowocześnieniu oraz przyspieszeniu prac wyburzeniowych na obiektach energetycznych. Nowoczesne platformy wyburzeniowe o dużej efektowności wiążą się z wieloma wyzwaniami. Hydrauliczne podciąganie na duże wysokości jak i praca platformy musi zapewniać bezpieczeństwo ludzi, maszyn i obiektów.
industrial chimneys. This article focuses on modernising and speeding up demolition works on energy facilities. Modern high performance demolition platforms involve many challenges. Hydraulic jacking to high heights as well as the operation of the platform must ensure the safety of people, machines and objects.
workpieces with abrasive media. While in the second step, smoothing - polishing with metal media was performed. Vibratory polishing also strengthened the treated surfaces. The test results were compared for samples in the crushed state (work hardening, plastic processing) and samples subjected to recrystallization annealing heat treatment. Mass losses, changes in the geometric structure of the surface and changes in the hardness of the machining surfaces were analyzed. Samples subjected to recrystallization, as compared to the samples in the state after work hardening-plastic working, are characterized by a slightly higher arithmetic mean surface roughness and lower surface hardness than for analogous processes for samples not subjected to heat treatment. Heat treatment of annealing allows to remove the effects of crushing and thus it is possible to obtain larger mass losses. Smaller burrs dimensions were obtained for samples after the heat treatment – annealing than after work hardening.
better object. The technique of “Six Thinking Hats” using lateral thinking was also characterized. This type of thinking is characterized by problem-solving by looking at things differently than usual. The article shows how to create creative solutions using heuristic methods. The list of requirements for innovative cleaning equipment was made through the use of an “ideas crushing” method called reverse brainstorming. After answering a series of crushing questions, appropriate conclusions were drawn. Subsequently, the defects found were catalogued according to their type, and those that did not bring tangible benefits in relation to the costs of their removal, were rejected. At the last stage of the method, possible solutions to the most important disadvantages were proposed. The practical application of the “Six Thinking Hats” method was also presented. It allowed to consider the problem from the point of view of several areas: emotions, facts, optimism, pessimism, innovative ideas, logical thought process. The described methods can be used in other areas of industry and life.
with a grain size of up to 2 mm with the smallest possible fraction of less than 0.5 mm, which will allow obtaining a product that meets the requirements of customers. The technological system should allow for a minimum efficiency of 20 Mg/h of product. The tests were carried out on two types of crushers: a Vibratory jaw crusher and a hammer crusher with a variable grate size. Based on the analysis of the research results, the use of a hammer crusher was proposed. Using this type of crusher with an adequately selected grate allowed to obtain satisfactory results. It was also proposed to modify the crusher’s functional elements (hammers), which should increase the efficiency of the process.
frakcji poniżej 0,5 mm co pozwoli na uzyskanie produktu spełniającego wymagania odbiorców. Układ technologiczny powinien pozwolić na uzyskanie wydajności wynoszącej minimalnie 20 Mg/h produktu. Badania przeprowadzono na dwóch typach kruszarek: szczękowej kruszarki wibracyjnej i kruszarce młotkowej ze zmiennym rusztem. Na podstawie analizy wyników badań zaproponowano zastosowanie kruszarki młotkowej. Zastosowanie tego typu kruszarki z odpowiednio dobranym rusztem pozwoliło na uzyskanie zadawalających efektów. Zaproponowano również modyfikacje elementów roboczych kruszarki co powinno pozwolić na zwiększenie efektywności procesu.
dissimilar thickness (LWTBs), and these were deformed using a two stage deep drawing setup to fabricate geometrically similar drawn cups consisting of both hemispherical and cylindrical segments. Subsequently, these drawn cups were axially crushed between two flat platens to study collapse modes, load–displacement responses and energy absorption capabilities. The collapse of the drawn cups was found to onset with an inward dimpling of the hemispherical segment. As deformation progressed, the folding of cylindrical section occurred either axisymmetrically or unevenly based on the extent of non-uniform thickness variations across the weld zone (WZ). It was also found that the load–displacement response and energy absorption of the cups were enhanced because of the presence of WZ and thickness difference in LWTBs. Also, finite element-based numerical models were developed to collate the prediction capabilities of three different anisotropic material models viz. Hill48, YLD89, and Stoughton non-associated flow rule (S-NAFR)-based model. All these material models were successfully calibrated to predict the collapse modes, but the S-NAFR model was found to closely predict the load–displacement curves and energy absorption. Furthermore, the assessment of specific energy absorption and crushing force efficiency suggested that lightweight LWTB components can be fabricated with improved crashworthiness performance using sheet materials of different thickness.
flexibility of the model was substantiated by its capability of describing and estimating the inward folding in frusta in general as well as in cylinders as a special case. A declining trend of the eccentricity dependence with the D/t ratio was found in contrast with a previous theory which suggests total independency. ABAQUS 14-2 finite element software was employed to simulate the thin tube as a 3-D thin shell part. Numerical simulations of the process were found to, firstly, underestimate the theoretical values of inward folding in general, secondly anticipate more underestimations as the tubes become thinner and/or have larger apex angle, and finally anticipate as low as 300 apical angle frusta to revert its mode of deformation to global inversion.
of multiple regression of the second order and their adequacy was checked by the Fisher criterion. Rational operating parameters were obtained by Cramer's method using the “Mathcad 15.0” software.
wielokrotnej drugiego rzędu i ich adekwatność sprawdzono za pomocą kryterium Fishera. Racjonalne parametry pracy uzyskano metodą Cramera przy użyciu programu „Mathcad 15.0”.
optimum time. In this study, the changes in the specific rate of breakage of the quartz sand sample were investigated by using cylpebs of three different sizes. For this purpose, three different mono-size samples were prepared according to 4√2 series in the range of 0.090-0.053 mm. The quartz sand prepared in these three intervals were ground with 10×10, 20×20 and 30×30 mm cylpebs for different durations. Specific rate of breakage values were obtained from the particle size distributions acquired after various grinding periods. As a result of grinding tests, an increase in rate of breakage is observed due to the increase in cylpebs diameter.
drops. It is determined the possibility of using the model to define the processes of displacement, deformation or fragmentation of the inclusion of the dispersed phase under the influence of a set of neighboring particles. The proposed method allows us to determine the main energy parameters of the homogenization process by boiling the emulsion.
do zdefiniowania procesów przemieszczenia, deformacji lub fragmentacji włączenia fazy rozproszonej pod wpływem zestawu sąsiednich cząstek. Proponowana metoda pozwala określić główne parametry energetyczne procesu homogenizacji podczas ogrzewania i wrzenia emulsji.
diameter of 20 mm and a height of 34 mm. The specimens were subjected to compression under various speed conditions (static, dynamic and SHPB tests). The calculated specific energy absorption values showed a 50–60% decrease with increasing process velocity and depending on the type of specimens architecture. The highest energy values were absorbed by the specimens with the highest share of axial fibres in the sample.
przenośnikami taśmowymi na istniejący zakład przeróbczy. Jakie wyniki uzyskano po realizacji inwestycji? Jak wypadły one w stosunku do założeń dokonanych w pierwszym etapie projektu?
crushers. One of the methods of reducing the amount of energy expended on the crushing process is reducing the number of crushers in technological line. By replacing a large number of less effective crushers with fewer machines but characterized by higher crushing efficiency we can gain considerable savings in investment and operating costs. This is possible by using crushers capable of obtaining much greater degrees of fragmentation than the aforementioned, that is vibratory crushers. The paper includes the systematic of currently used vibratory crushers, their mechanical diagrams, descriptions of the construction and operation, and basic technical parameters as well as examples of crushing technological lines utilizing vibratory crushers.
electrical energy used on the crushing process was measured as a function of changing design and kinematic parameters of the vibratory crusher, i.e.: jaws stroke, the outlet gap size and frequency of jaws vibration. The article presents program of the research, the laboratory test stand of the vibratory jaw crusher KW 40/1 and the test results. Comparing the theoretical crushing energy requirements, determined by the Bond hypothesis, with the values measured during tests a large differences were observed. Using the Bond hypothesis the Vibratory Work Indexes were determined for the tested materials. Their values are higher than limestone and diabase Work Indexes available in the known literatures. The explanation may be greater amount of energy transferred to the material during vibratory crushing, which results in much higher efficiency of the crushing process.
ilości powstającej frakcji piaskowej.
test material is obtained. It is reported that the electropulse processing at the reduction stage made for significant increase in the content of non-ferrous and rare metals.
przewodów strzelniczych i przybitki strzelniczej. Obecnie stosowany proces technologiczny wzbogacania polega na rozdrabnianiu w kruszarce udarowej i wydzielaniu rozdrobnionych zanieczyszczeń przy pomocy separatorów magnetycznych i przesiewaczy. Ponieważ w klasie ziarnowej powyżej 20 mm znajduje się większość zanieczyszczeń, traktuje się ją jako odpad. W rzeczywistości, oprócz zanieczyszczeń znajdują się w tej klasie bardzo duże ilości soli, ok. 98%. W Katedrze Maszyn Górniczych Przeróbczych i Transportowych Akademii Górniczo - Hutniczej w Krakowie podjęto próbę wydzielenia z tego typu odpadu produktu handlowego. Propozycja polega na zastosowaniu wibracyjnej kruszarki szczękowej z wymuszeniem bezwładnościowym, a następnie wydzieleniu z produktu kruszenia zanieczyszczeń na odpowiednio dobranych sitach. Zastosowanie kruszarki tego typu umożliwia selektywne kruszenie wyżej wymienionego odpadu (rozdrobnieniu ziaren soli, pozostawiając nierozdrobnione odpady postrzelnicze). Umożliwiło to wydzielenie odpadów od soli, która może być wykorzystana jako pełnowartościowy produkt handlowy.
excavated salt. The existing technological process of enrichment consists in crushing in impact crushers and separation of shredded impurities by means of magnetic separators and screens. Most contamination stays in the grain class above 20 mm, therefore this class is treated as a waste. In fact, this class – apart from unwanted impurities – contains a very large amount of salt, about 98%. In the Department of Mining, Dressing and Transport Machines of the AGH University of Science and Technology in Krakow, an attempt was made to extract the commercial product from this type of waste. The proposal is to use a vibratory jaw crusher with inertial actuation of jaws and then separate impurities from the crushing product on appropriately selected screen. The use of this type of crusher enables selective crushing of the abovementioned waste (crushing salt grains and leaving waste nonfragmented). This process enabled the separation of waste from salt, which could be used as a standard value commercial product.
kruszarki szczękowe, stożkowe lub udarowe. Jednym ze sposobów obniżenia ilości energii wydatkowanej na proces kruszenia jest zmniejszenie liczby kruszarek w linii technologicznej. Jest to możliwe przez zastosowanie kruszarek charakteryzujących się dużo większymi stopniami rozdrobnienia niż wspomniane wcześniej, czyli kruszarek wibracyjnych. W pracy opisano budowę, zasadę działania oraz podstawowe parametry techniczne kruszarki wibracyjnej KW 40/1, która jest wyposażona w wibratory kinematyczne z możliwością regulacji skoku szczęk. Przedstawiono również wyniki własnych badań pokazujące możliwości technologiczne kruszenia wibracyjnego przy rozdrabnianiu materiałów pochodzenia naturalnego, jak również wytworzonych sztucznie.
crushers. One of the methods of reducing the amount of energy expended on the crushing process is reduction of the number of crushers in a technological line. This is possible by the use of a crusher characterized by much greater degrees of fragmentation than the aforementioned ones, i.e. vibratory crushers. W pracy opisano budowę, zasadę działania oraz podstawowe parametry techniczne kruszarki wibracyjnej KW 40/1, która jest wyposażona w wibratory kinematyczne z możliwością regulacji skoku szczęk. A construction, principles of operation, and basic technical parameters of a vibratory crusher KW 40/1 equipped with kinematic vibrators, that have a controlled travel of jaws, are described in the paper. The results of studies are also shown illustrating technological performance of the vibratory crushing in case of different raw and artificial materials.
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