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2017
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tom nr 2
113--120
EN
The article analyses properties of magnetic fluid seals installed in rotary sealing nodes which operate in the utility water environment. Seals of this type have been examined as a possible solution to the problem with ship manoeuvring propulsion sealing. The present analysis bases on laboratory durability tests of magnetic fluid seals exposed to longterm utility water loads, at different water pressures and shaft revolutions. The basic seal durability criterion was the number of revolutions made by the sealing node shaft until the appearance of water tightness loss (leakage). It was found that the main factor leading to the wear of the seal is the relative speed of the magnetic fluid with respect to that of the utility water, and this process is heavily affected by the pressure acting on the seal. The reported test results are presented in the form of diagrams showing the seal durability (time until water tightness loss) as a function of rotational speed. The curves shown in the diagrams are regular, with two different rotational speed ranges: the highspeed range, when the tightness loss is relatively fast, and the low-speed range, with a clear tendency to prolong the seal lifetime. These diagrams were given the name of durability curves of the MF seal operating in water. The results of the performed tests suggest formal similarity between the experimental data distribution concerning tightness loss processes occurring in magnetic fluid seals operating in water environment and metal fatigue processes. The article proposes a preliminary simplified durability model to describe the examined phenomenon.
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tom nr 136
55--64
EN
This paper presents the influence of geometry simplification on the results obtained in the computational fluid dynamics simulation. The subject of simulation was part of the honeycomb seal located at the inlet to high pressure part of a steam turbine. There were three diferent geometrical models assumed in the calculations. First one was two-dimensional case and two others were three-dimensional, one with the radius of curvature and one without. Numerical simulations were performed for 15 sets of boundary conditions to compare flow characteristics for each geometrical case.
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2008
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tom Z. 10, Vol. 1
279-286
EN
NPO Energomash's experience in creating an electrical component, which can be used to control high-energy compressed gas flows in rocket production, as well as aviation and other industries, is described.
EN
Experience in developing and making the detachable joints (DJ) of the liquid-propellants rocket engines (LPRE) lines and components with elastic metal seals is described. DJ requirements, criteria of selection of design, materials and coatings; DJ parts and elastic seals calculation aspects as well as results of integrated studies which have proved the operability, leakproofness and reliability of the developed designs are presented.
EN
Considering the key equipment of the pipeline clamp repair technology, this paper analyzes design of the pipeline repair clamp. Based on the damaged pipeline repair requirements, the design of a double-sealing pipeline repair clamp is established. The subsea pipeline in the Bohai Bay is considered as an example to develop a finite element model of a double sealing structure and calculate the sealing capacity, targeting a sealing pressure of 6MPa. The parameters affecting the sealing capacity are studied. For circumferential sealing, the effects of distance between the rubber and the pipeline, distance between the ring and the pipeline, and the contact friction coefficient on the sealing capacity are analyzed. The design parameters of circumferential sealing are optimized by an orthogonal experimental design method. Further, the effect of the friction coefficient on the axial sealing capacity is studied, and design suggestions are put forward based on the analysis. The results of this study can provide guidance for the design and application of subsea pipeline repair clamps.
8
Content available remote Stick-Slip Vibrations of Pneumatic Seals
70%
EN
In the present paper the dynamic friction process of a pneumatic seal is investigated. A test facility for measuring forces, displacements and velocities on a lubricated seal lip has been used. The measurements indicate that the friction force depends on several parameters. Stick-slip effects are found in the low velocity range. After the identification of the system parameters these vibrations have been modelled. It turned out that dynamic friction force can be described well by a first order differential equation.
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tom 76
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nr 3
31-57
EN
The article concerns the iconography of the seal of Anne of Bohemia, Duchess of Silesia. In the analysis of its message particular attention was given to the object held by the duchess in her hand, which has been contradictory interpreted in historiography. The author has proven that it is the fleur-de-lys, symbolizing purity and sanctity – important values in life of the duchess to whom the sigillum belonged.
EN
A number of hydrocarbon accumulations with recoverable reserves ca. 6.5 million tons of oil equivalent, e.g. Grobla, Pławowice, Łąkta, Tarnów-Jurassic, Dąbrowa Tarnowska, Smęgorzów, Gruszów, Partynia-Podborze, Korzeniow, traped within the epicontinental Upper Jurassic formations have been discovered so far in the Polish Carpathian foreland and the Carpathian basement (Fig 1). The traps are of combined structural and stratigraphic type. Reservoir rock types are found to vary between matrix-dominated porous rocks to dual-porosity and dual-permeability rocks and from porous fractured to entirely fractured rocks. The types of reservoir rocks could ultimately be linked to sediment type, diagenetic processes, and position in the basin. Location of hydrocarbon accumulation is strictly connected with fault systems developed within the Mesozoic formations. The traps are sealed by Miocene claystones-mudstones and/or Upper Cretaceous marls. Results of recently carried out analysis of the petroleum system, especially identification of sufficient source rocks combined with effective geochemical and thermodynamic conditions for hydrocarbon generation and migration, indicate that there are still perspectives for further oil and gas discoveries within the Mesozoic formations, especially the Upper Jurassic ones. Using modern techniques of geophysical and geological data acquisition, integration and interpretation, like e.g. modeling of seismic images by artificial neural networks, is crucial for further successful exploration. It enables us for identification and classification of different genetically hydrocarbon traps. Interpretation of 2D and 3D seismic images is carried out using several additional procedures connected with PAL and RAVE applications of the Landmark Inc. software package. Also, additional analysis of seismic data based on differentiation of frequency image for particular objects like Fourier & Karhunen-Loeve transformations and spectral decomposition is used. Recently, a detailed facies and stratigraphic analysis of the Mesozoic formations of the Carpathian foreland resulted in defining some new possibilities of finding hydrocarbon fields within traps of a combined stratigraphic and tectonic type. Existing fields were used as case stories for identification of criteria for finding new prospective traps. Taking into account regional tectono-stratigraphic model of evolution of the Late Jurassic-Cretaceous sedimentary basin gives a perspective for further successful exploration in the areas formerly regarded as non-prospective.
EN
The method for the selection of a calculation scheme for the evaluation of the flow behaviour of labyrinth seal with one straight fin, against smooth wall, was presented. Experimental results were obtained from measurement data carried out on the in house, vacuum test section. The advantage of the test rig is a circular shape of the labyrinth specimen, providing similar shape to configuration operated in practise. In computational fluid dynamics study different types of mesh resolution were tested, with variable volume discretization in the area of a labyrinth fin tip. Moreover, a wide range of turbulence models basing on k-ε and k-ω, exploiting the (Reynolds Average Navier Stokes) scheme, for the flow pattern evaluation, were examined. All obtained results were compared with literature data, covering research conducted on similar configurations. The presented study shows challenges as well as the possibilities of calculation simplification and compares results obtained by means of simulations and experiment. The proposed method is characterised by excellent agreement of computational results with experiment data.
13
60%
PL
W pracy przedstawiono niektóre zagadnienia występujące w uszczelnianiu węzłów konstrukcyjnych, w których zastosowano elastyczny pierścień kształtowy typu "O". Zwrócono również uwagę na dość powszechne stosowanie tego rozwiązania w urządzeniach eksploatowanych w przemyśle spożywczym. Jednym z kryteriów oceny takiego węzła uszczelniającego jest spełnienie najwyższych standardów sanitarno-higienicznych. Uzyskanie wymaganej szczelności w największym stopniu zależy od rodzaju materiału i deformacji uszczelki, a także od optymalnej geometrii ścianek w miejscu osadzenia uszczelnienia typu "O-ring". Dla wyznaczenia średnich nacisków i długości tworzącej walca w miejscu kontaktu uszczelki przeprowadzono analizę numeryczną z zastosowaniem MES, z obliczeniami w programie ANSYS oraz z oszacowaniem właściwości materiału elastycznego według modelu Mooney-Rivlina. Wyniki obliczeń deformacji uszczelki i odpowiadające im wartości naprężeń potwierdzają istnienie w przekroju uszczelki charakterystycznych punktów Bielajewa.
EN
In this paper some chosen aspects of the elastic O-ring behaviour and its design place seen mainly as the features of surrounding surfaces in variety of seals joints have been considered. The main attention was focused on the mostly expected criteria, i.e., to keep the seals at the highest hygienic standards, and to prevent or minimise leakage of fluid in the food industry equipment. It has been stated that the assessment of the sealant deformation value and the stress propagation mechanism, are the matter of most importance in the designing process of seals used in many of industrial application. As for seal design, and for characterising the elastic behaviour of the O-ring material requirements, the Mooney-Rivlin model was applied. Based on the ANSYS programme together with finite-element stress analysis and computer modelling, the calculation and description of deformation and stress phenomena have been presented. For the above values the special zone treatment of the Bielajev's points can also be pointed out and concerned.
14
Content available remote Technologia montażu uszczelnienia wału wejściowego reduktora
60%
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2014
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tom nr 2
98--101
PL
W artykule zaprezentowano mechatroniczne urządzenie do montażu pierścienia uszczelniającego wał wejściowy reduktora w procesie produkcji seryjnej. Technologia montażu uszczelnienia wału wejściowego reduktora w produkcji seryjnej jest procesem zależnym w znacznej mierze od obowiązującego u wytwórcy systemu zapewnienia jakości. Wyższe wymagania stawiane przez system decydują o technicznym wyposażeniu gniazd montażowych eliminującym błędy wynikające z subiektywnej oceny lub działań intuicyjnych człowieka. Zastąpienie ręcznych narzędzi montażowych specjalizowanym urządzeniem pozwala na prowadzenie montażu w stałych warunkach zapewniających osiągnięcie założonego celu: wciśnięcie uszczelnienia na stałą głębokość w sposób gwarantujący skuteczność uszczelnienia. Opracowane rozwiązanie umożliwia montaż uszczelnienia w reduktorze, zamocowanym trwale na wózku transportowym, przemieszczanym pomiędzy poszczególnymi gniazdami technologicznymi. Sterowane mikroprocesorowo urządzenie montażowe, sprawdzające obecność pierścienia przeznaczonego do montażu oraz głębokość, na jaką pierścień jest wciskany, zapewnia pełną kontrolę nad realizacją procesu. Pozyskana z montażu informacja o jego wyniku pozwala na dalsze efektywne wykorzystanie w sterowaniu jakością całego procesu wytwarzania.
EN
The article presents a mechatronic device of a seal ring assembly for an input shaft of a reducer in batch production. The technology of this assembly is highly dependent on the quality inspection system used by the manufacturer. Higher requirements of the system determine the technical equipment of fitting sockets that eliminate errors resulting from a subjective assessment or an intuitive human activity. Replacing manual assembly tools with a specialised device enables the assembly to be conducted in constant conditions, which guarantees that the assumed objective is met, i.e. the placement of a seal at a constant depth in a way that ensures the effectiveness of the seal. The device enables to assembly the seal in a reducer fixed onto a trolley that moves from one technological slot to another. The assembly device, controlled through the microprocessor, checks the presence of a ring and the depth at which it should be placed. This step guarantees full control over the assembly process. The information about the outcome of the assembly allows a further application of the device for the inspection of the entire assembly process quality.
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tom Z. 50
43-50
PL
Przeprowadzono badania klejów anaerobowo-stykowych, jako uszczelniaczy w połączeniach gwintowych ze szczególnym zastosowaniem ich w instalacjach hydraulicznych ciepłej i zimnej wody użytkowej oraz centralnego ogrzewania, wydając pozytywną opinię o ich przydatności do pełnienia tego typu funkcji.
EN
Investigations have been carried out of anaerobic-contact adhesives as leak stoppers in screw joints, paying special attention to their use in hydraulic installations for hot and cold consumption water and central heating installations. A positive opinion of their usefulness for performing this type of functions has been given.
EN
This study developed a novel measurement system for the friction force characteristics of pneumatic cylinders. The dynamic characteristics of pneumatic cylinder are affected by guide seal, piston seal, grease and surface of cylinder bore. In seeking to improve the friction force characteristics of pneumatic cylinders and to clarify the friction phenomenon of the pneumatic cylinders, this study describes friction force measurement tests to measure the friction force of pneumatic cylinder, under both dry and lubricated conditions. Experimental equipments are designed to assess the effect of seals and lubrications in pneumatic cylinder, where the velocity and pressure of the driving cylinder are controlled. Measurements of friction force are shown for velocities of up to 200 mm/s. This paper provides an easy and accurate measurement system to analyze the friction characteristic of pneumatic cylinder. The data obtained will be useful for developing a suitable friction model, and the experimental apparatus will facilitate the study of the effects of different types of seals and lubricants on friction force.
PL
W artykule zaproponowano nowy system pomiarowy do analizy siły tarcia w cylindrach pneumatycznych. Celem jest poprawa charakterystyk tarcia i dlatego badania przeprowadzono w warunkach suchych i mokrych przy kontrolowanych szybkości i ciśnieniu.
PL
Opisano i wyjaśniono zjawiska fizyczne mające wpływ na wartość i rozkład ciśnienia w zespole technologicznym pieca obrotowego obejmującym komorę żużlową, piec i komorę osadczą. Określa się zależność wielkości ciśnienia w komorze żużlowej od stopnia doszczelnienia tej komory i ilości zaciąganego powietrza do pieca. Przedstawiono wzory pozwalające określić dopuszczalne wielkości nieszczelności komory żużlowej, przy których nie występują wycieki gazów na zewnątrz. Wykazano konieczność stosowania uszczelnień dolnej i górnej końcówki pieca.
EN
The article describes and explains physical phenomena having influence on pressure value and its distribution in a technological set of a rotary kiln including a slag chamber, a furnace and a dust chamber. It specifies relation between pressure quantity in the slag chamber and degree of this chamber's seal and quantity of air sucked into the furnace. There is formula, which let specify permissible size of leakage of the slag chamber, by which there are no gas effluents outside, presented here. The necessity to use seal of bottom and upper the furnace's terminals is indicated.
19
60%
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2016
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tom 8
s. 181-230
PL
Pieczęcie cechowe są ważnym i nadal słabo rozpoznanym działem sfragistyki. Interesująca kolekcja tego typu zabytków jest przechowywana w Muzeum Diecezjalnym w Płocku. Jej twórcą był Franciszek Tarczyński, a skatalogował ją ks. Tomasz Kowalewski. Znalazły się w niej pieczęcie cechów z Chodzieży, Kowala, Łowicza, Sandomierza, Starej Warszawy, Płocka i Włocławka.
EN
Guild seals are an important and still poorly recognized in the historiography of science department of sfragistic. Interesting collection of monuments of this kind has been collected in the Diocesan Museum in Plock. It was created by Franciszek Tarczyński, and cataloged by priest Tomasz Kowalewski. The stamps have been affixed to his cardboard boards. Stock of the guilds of Plock, Lowicz, Sandomierz, Old Warsaw, Kowal, Chodziez, and Wloclawek.
20
Content available remote Uszczelnienie i wentylacja domu szkieletowego
60%
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