In the autumn of 2014 were performed the geochemical research of the soil gases composition in the area of selected oil mine in southern Poland. For a total were carried out of 75 individual analysis at 55 measuring points. The average depth of the measuring point was about 84.4 cm. The grid selection of the measurement points was made ad hoc, taking into account arrangement the existing mine installation and the location of the abandon wells. Finally, geochemical studies were performed in the vicinity of 6 exploitation wells (1 liquidated, one flowing well and 4 pumped periodically), on the route of transmission pipelines and in the area of group centers. The free choice of the measurement point location was limited by buildings and agricultural crops. In the area of the analyzed deposit were drilled more than 100 wells, most of which were liquidated and usually did not stay after them no trace on the surface. Based on the results of the geochemical research of the soil gases composition there was determined the spatial distribution of the methane concentration in the soil in the nodes of a regular grid by geostatistical methods using kriging. On this bases there were developed the maps of the methane concentration. Generally, on the oil deposit site there were detected two areas with the increased methane concentration in the ground. The distribution of the methane concentration in soil on the first one shows the installation leak in the vicinity of several wells. In the second much smaller area it may suspect that the pipeline transporting crude oil to the group centre is leaky. In the research area are vast cultivated fields of high oxygenation and small wet ground. There are no permanently wetlands areas. This means that in soil occur at most aerobic rot and decay processes, resulting in the production of carbon dioxide but not methane. There is no reason to assume that occur also the natural anaerobic putrefaction processes. Therefore, the detected abnormally high methane concentration in the ground is not of biological origin. To confirm formulated hypothesis should also be do the chromatographic research of C14 carbon isotope content in the taken methane samples from the soil to determine his age and confront it with the age of methane produced from the deposit. In general, the results analysis of the geochemical research of the soil gases composition leads to the conclusion that the rock mass is hermetic from the geological point of view, but there are occasional leaks in the production system of several wells and transmission pipeline, that can remove.
Enhanced oil recovery methods can significantly increase recovery from offshore oil reservoirs provided that the appropriate method is selected. Enhanced oil recovery methods aim to recover the remaining original oil in place by applying additional energy sources and minimalize flow resistance in the field. The application of these technologies results in enhancement, or replacement of natural or physical processes of displacement and modifies the composition and physical properties of formation fluids. The use of EOR technologies in offshore environment is limited compared to onshore fields. Constraints imposed by the offshore environment are associated with technical difficulties as well as economic risk. Before choosing the most appropriate EOR method for particular environmental conditions the restrictions associated with: large well spacing, disposal geological description as well as availability and cost of EOR agents, weight and space constrains or high capital cost requirements should be considered. Reservoir lithology is limiting the applicability of specific EOR methods. This paper presents a comprehensive review of EOR projects which are appropriate or possible for sandstone reservoirs containing light-oil in offshore field. The possibilities and limitations of selected methods are introduced.
In the years 1993-1994 International Organization for Standardization (ISO) introduced to the metrology the fundamental changes of basic character, involving - in addition to the traditional concept of measurement error - the use of new fundamental term of uncertainty of measurement. In consequence, this has led to currently undisputed axiom of metrology, that the measurement result has a form of a section on dimensional axis. These rules of presenting measurable physical values should be reflected in the of practical procedures of mathematical modeling. Presented work relates to this particular problem. It discusses the principles of mathematical modeling together with the assessment of the results. Particular attention was paid to the identification of possible systematic errors (i.e. the load of model) and to estimating the uncertainty of the statistical and deterministic modeling.
4
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
W pracy przedstawiono ogólne warunki wprowadzenia zmian w przepisach krajowych po przystąpieniu Polski do Unii Europejskiej ze szczególnym uwzględnieniem Dyrektywy 2001/45/EWG, dotyczącej minimalnych wymagań ochrony zdrowia i bezpieczeństwa w stosunku do sprzętu używanego przez pracowników podczas pracy. Dla dokonania kompleksowej oceny maszyny w zakresie minimalnych wymagań dotyczących bezpieczeństwa i higieny pracy w zakresie użytkowania przez pracowników podczas pracy przedstawiono propozycję zapisów z wykonanego sprawdzenia.
EN
In this work presented are general conditions for introducing modifications (amendments) in the national regulations upon joining the European Union by Poland, with taking into account the Directive of 2001/45/EEC pertaining to the minimal requirements as regards health protection and work safety relative to the equipment used by the workmen when performing their work. To complete a comprehensive assessment of the machine in respect of the minimal requirements pertaining to health protection and work safety in operating to health protection and work safety in operating it by the workmen in the course of their work presented is a proposal of making records concerning the inspection performed.
6
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Efficiency of absorbing layers of various composition covered by various methods has been investigated using convergent specimens. These coatings consisted of Al2O3, iron oxide graphite SiO2 (paste) and Al2O3, B4C, Cr2O3 (plasma). The specimens were heated by CO2 laser (lambda=10,6 micrometer), power 2 kW, rate of scanning 500 mm/min. Efficiency was determined by measuring maximal thickness of melted through specimen. Additional metallographic examination in the section of maximal melting thickness has been performed, what enabled to determine the structure of melted area. It was stated that coating efficiency is the function of chemical composition and covering of the coating method.
W pracy zbadano efektywność działania powłok absorbcyjnych nanoszonych różnymi metodami i o różnym składzie chemicznym. Zastosowano w praktyce metodę określania absorbcyjności za pomocą próbki zbieżnej. Testowano warstwy nakładane plazmowo i w postaci past. Materiały natryskiwane plazmowo to Cr2O3, TiO2, Al2O3, B4C, CrO2. W postaci past nałożono Al2O3, mieszaniny tlenków żelaza, grafitu, SiO2. Naniesione warstwy przetopiono laserem CO2 o długości fali 10,6 μm i mocy 2000 W. Prędkość przesuwu wiązki wynosiła 500 mm/min. Efektywność działania wiązki sprawdzono mierząc długość przetopu na wskroś próbki zbieżnej. Dodatkowo przeprowadzono badania metalograficzne przekrojów w miejscach końca przetopu na wskroś. Pozwoliło to na określenie efektywnej wielkości przetopu. Badania wykazały, że efektywność działania powłoki nie zależy od wielu czynników, w tym od sposobu nanoszenia powłoki, tylko od jej składu chemicznego.
EN
Efficiency of absorbing layers of various composition covered by various methods has been investigated using convergent specimens. These coatings consisted of Al2O3, iron oxide, graphite, SiO2 (paste) and Al2O3, B4C, Cr2O3 (plasma). The specimens were heated by CO2 laser (lambda=10,6 μm), power 2 kW, rate of scanning 500 mm/min. Eficiency was determined by measuring maximal thickness of throughout melted specimen. Additional metallographic examination in the section of maximal maleting thickness has been performed, what enabled to determine the melted area. It was stated that coating efficiency is the function of chemical composition and covering method.
9
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
The solid particle erosive wear resistance of a hardfacing coating among else depends on properties of the material to be formed by a coating technology used. In the current investigation a laser surface cladding and plasma transferred arc methods have been used to obtain a Stellite 6 alloy deposits on Iow carbon steel substrate. A microstructure, hardness, wear resistance and solid particle erosive wear behavior have been evaluated depending on the coating process. In the test conditions the plasma transferred arc deposited alloy had a better wear resistance over that of the alloy deposited by laser cladding. That was a result of a susceptible for plastic deformation coarse-grained microstructure formed in the material during plasma arc process.
PL
Odporność warstw napawanych na zużycie przez erozję w strumieniu cząstek zależy m. in. od własności użytych materiałów, ściśle związanych z technologią wykonania powłok. W pracy do wykonania warstw ze stopu Co-Cr-W-C - na podłożu ze stali węglowej zastosowano natapianie laserowe oraz napawanie łukiem plazmowym. Porównano mikrostrukturę, twardość, odporność na zużycie oraz zachowanie się materiału poddanego erozji w zależności od metody natapiania. W warunkach testu stwierdzono wyższą odporność na zużycie materiału napawanego łukiem plazmowym, co wynikało z uzyskania struktury gruboziarnistej, podatnej na odkształcenie plastyczne.
Istniejące maszyny tribologiczne nie nadają się do badania przetopów laserowych, które są wąskie i cechują się zmienną strukturą na głębokości przetopu, a więc i zmienną odpornością na ścieranie. W celu umożliwienia zbadania odporności na ścieranie różnych stref strukturalnych w laserowym przetopie zbudowano urządzenie z wirującą tarczą o grubości ok. 3 mm, która wyciera w dociskanej do niej próbce rowek o płaskim dnie, dzięki wykonywaniu przez próbkę ruchu posuwisto-zwrotnego. Ponieważ urządzenie to automatycznie wyłącza się po zadanej liczbie obrotów tarczy, umożliwia to określenie ubytku masy próbki w funkcji drogi tarcia. W urządzeniu tym tarcza może być chłodzona wodą (ewentualnie z dodatkiem ścierniwa) albo olejem. W razie potrzeby można określić silę tarcia, a więc wyliczyć współczynnik tarcia. Na maszynie zbadano warstwy stopów Tribaloy T-400 i Stellit 6 natapianych laserowo oraz napawanych łukiem plazmowym.
EN
The existing tribological machines are not ouite suitable for laser processed material examination. Laser treated tracks are narrow and have alternating structure on their depth, thus changing their abrasive wear resistance. To examine this property in zones showing various structure a machine has been constructed with a 3 mm thick rotating disc. A resulting groove on the sample surface due to wear action shows a flat bottom. This is due to reciprocating motion of the sample in respect to the rotating disc. Because machine is able to switch off automatically after a numer of disc revolutions set, it is possible to determine the mass loss as a function of friction distance. In the machine the disc may be cooled with water (possibly with abrasive medium) or with oil. It is possible to determine the friction force and calculate the coefficient of friction. The machine was applied to investigate the wear resistance of laser cladded Tribaloy T-400 and Stellite 6 alloys.
W artykule omówiono formowanie struktury warstw wierzchnich (W W) i powłok w procesie laserowej obróbki mateńałów. Uwzględniono przemiany fazowe zachodzące w stalach i stopach, w stanie ciekłym i stałym, w czasie gwałtownego krzepnięcia i chłodzenia do temperatury otoczenia. Teoretyczne rozważania zostały zilustrowane wynikami badań w zakresie obróbki laserowej prowadzonych przez autorów na przestrzeni minionych lat. W szczególności artykuł dotyczy następujących zagadnień i mateńałów: struktury i własności żeliwa sferoidalnego Gh60, struktury i własności odlewanej stali szybkotnącej SW 18, struktury i własności laserowo stopowanej tantalem stali węglowej oraz struktury i własności erozyjnych powłok ze stopu Tńbaloy T-400 natapianych laserowo.
EN
Structure forming of upper layers (UL) and coatings during laser working of mateńals is presented. Consideration was given to phase changes in steels and alloys in liquid and solid state duńng violent solidification and cooling to amabient temperature, Theoretical considerations were illustrated by testing results of laser working carried out by authors duńng last years. In particular the paper presents following problems and mateńals: structures and properties of high-speed steel SW18, structures and properties of carbon steel laser alloyed by tantalum and structures and erosion properties of laser remelting Tńbaloy T-400 coatings.
In the paper experiments have been performed to find out composition of the coatings producing exothermic reaction in them under the influence of laser beam counteracting the change of steel composition and radiation of heat. The coatings are based on iron oxides mixed with carbon or metal powders of high reductive properties (silicon, magnesium, aluminium). The results have shown, that the coatings ensured high conductivity and absorptivity of heat and in many cases their neutral behaviour on heated surface has been stated.
The laser deposited coating of Tribaloy T-400 cobalt base alloy containing Mo, Cr and Si has been subjected to solid particle erosion. Changes in alloy surface layer morphology and microstructure due to intensive particles impact have been studied by means of scanning and transmission electron microscopy. Three zones ranging down to 30-40 micrometers under the eroded surface have been distingished regarding the microstructural effects observed. The microstructure changed from nearly amorphous at the surface through strongly dislocated in the second zone to containing stacking faults in third zone.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.