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EN
Purpose: To improve the technologies of different oil types of sequential pumping through the pipeline by establishing the laws of changing the throughput and energy efficiency of the oil pipeline operator in the process of pumping and displacing oil batches. The identified regularities would contribute to more effective management of the mixture realisation process at the end of the oil pipeline and reliable forecasting of the results of the different oil types of mixture formation. Design/methodology/approach: Carrying out theoretical studies and applying mathematical modelling methods in order to establish the regularities of hy-drodynamic processes during the injection into the oil pipeline and the displacement of oil different grades from it. Findings: The regularities of changes in oil pipeline capacity and specific electricity costs for transportation as a function of the coordinates of different oil types of batches contacts and the time of sequential pumping cycle implementation they have been established. Research limitations/implications: The next stage of the research is to establish the influence of the hydrodynamic processes features on the intensity of the oil different grades mixture formation in the process of their successive pumping in the oil pipeline. Practical implications: A method and software have been developed that make it possible to predict the throughput and energy efficiency of oil pipeline operation for each moment of the sequential pumping cycle of small batches of different grade oil. The application of the method for the conditions of an operating oil pipeline proved that during the cycle of four types of sequential oil pumping, the change in throughput exceeds 20%, and the change in energy consumption exceeds 10%. Originality/value: The originality of the method consists in taking into account the regularities of the hydrodynamic process of the movement of several batches of oil of different grades in the pipeline, the features of the profile of the pipeline route and the physical properties of the liquid that fills the cavity of the pumps.
EN
We applied the detailed structural analysis to 394 outcrops in the southern and northern metamorphic cover of the Karkonosze Intrusion. We recognised five generations of fold structures: F1 -poorly preserved tight intrafoliation folds; F2 - the most common generation, with the whole variety of fold geometries, W-E and WSW-ENE-oriented fold axes in the northern contact zone, and W-E and WNW-ESE-oriented fold axes in the southern contact zone; F3 - chevron folds; F4 - kinkfolds observed only in the Stara Kamienica schist belt; and F5 - wide open folds, locally transformed into monoclinal kinkfolds, probably formed during the Variscan intrusion of the Karkonosze pluton. Similarity observed in the structural style in the northern and southern contact zones prove that these lithostratigraphic units had formed a single unit - the Izera-Kowary Unit - and had undergone the same deformational stages before the Karkonosze granitoid intrusion took place.
EN
The printing literature provides different values of pressure between cylinders in the printing unit and between rollers in the ink unit of the offset printing machine. Very often there is no information on whether a given value of pressure is maximum or average. Another frequent problem referred to in the printing literature is that authors do not reveal the source of theorems, equations or other important information. This article includes a set of values collected for pressure, line pressure, press clamping and the contact zone width that have been presented by other authors in their specific articles and books. It also includes definitions of pressure, line pressure, press clamping, indentation of blanket and metric clamping. In addition, the article briefly presents findings of the experimental research related to the contact zone between cylinders and rollers was carried out in the printing unit and in the ink unit until present. This article also gives publication references which provide for different equations concerned with the clamping force of cylinders, their compression or indentation, the contact zone width and the impact the specific stress-strain has on blankets.
4
Content available Monitorowanie temperatury skrawania
PL
Artykuł niniejszy omawia przykłady praktyczne różnych sposobów monitorowania temperatury skrawania. Omawiane metody badawcze zilustrowano w oparciu o przypadek toczenia ortogonalnego na sucho stali austenitycznej AISI 321 ostrzami węglikowymi H10F bez- i z powłokami ochronnymi o różnej konfiguracji warstw. W artykule szczególną uwagę poświęcono metodzie termoelementu naturalnego w odmianie jednonożowej oraz pomiarom termowizyjnym. W podsumowaniu pokazano zalety i wady omawianych metod pomiaru temperatury skrawania.
EN
The paper discusses practical examples of different ways of monitoring the cutting temperature. These test methods are illus-trated based on the case of dry orthogonal turning of AISI 321 austenitic stainless steel by cemented carbide inserts H10F with and without protective coatings of varied layer configurations. In this paper particular attention is paid to the natural thermocouple in single-point cutting. Examples of application of the test method (Figs. 2 and 4) are shown, and measurement chain calibration is discussed (Figs. 5 and 6). Table 3 shows the results of the calibra-tion, i.e. the contact temperature as a function of the thermoelectrical force for selected tribological pairs of the tool-workpiece material. Moreover, the paper deals in detail with the methodology of the infrared imaging of the temperature distribution in the cutting zone. The considerations are based on the temperature distribution analysis on the top of the chip, which is directly in contact with the atmosphere (Fig. 10). Based on the literature data [2, 8] and the results of own research [3] an original method of calibrating the thermal imaging measurement chain was proposed (Fig. 7). This allowed determining the emissivity of the chip surface in settings similar to cutting conditions. In conclusion, there are presented the advantages and disadvantages of the discussed cutting temperature measurement methods by referring them to the literature results and the results of own research.
PL
W artykule zaprezentowano oryginalną metodę wyznaczania momentu tarcia w łożyskach wieńcowych. Do analizy przedstawionych problemów wykorzystano metodę elementów skończonych i analityczny model tarcia tocznego. Obliczenia potrzebne do wyznaczenia rozkładu obciążenia wewnętrznego w łożysku i maksymalnej wartości siły obciążającej elementy toczne łożyska były przeprowadzone za pomocą procedur wykorzystujących system ADINA L. 8, 9]. Zamieszczono autorski model pozwalający na wyznaczanie współczynnika tarcia tocznego dla układu kulka–bieżnia łożyska. Przyjęte modele uwzględniają uwarunkowania techniczne przekazywania obciążenia zewnętrznego na elementy składowe łożysk wieńcowych podwójnych. Wyznaczono charakterystyki momentu tarcia, które zaprezentowano na tle charakterystyk nośności statycznej, odpowiadających zadanej wartości luzu łożyskowego.
EN
The original method to determine the friction torque for twin slewing bearings is presented in the article. The finite element method and analytic model of rolling friction has been used for the analysis of presented problems. The calculation to determine the maximum contact force on the rolling element was done using a ADINA program 8, 9]. The copyrighted model that made it possible to determine the various friction coefficients for contact zone ball–bearing race in slewing bearings is attached. Accepted models allow the estimation of the technical conditions of acting external load on component parts of twin slewing bearings. The profile of the carrying capacity and friction torque of twin slewing bearing for a constant value of bearing clearance is presented.
PL
W artykule porównano wybrane parametry łożysk wieńcowych podwójnych i jednorzędowych. W analizie uwzględniono wpływ luzu osiowego na zmianę charakterystyk nośności statycznej obu typów analizowanych łożysk. Przedstawiono wykresy momentu tarcia łożysk w odniesieniu do ich nośności statycznej. Do analizy przedstawionych problemów wykorzystano metodę elementów skończonych i analityczny model tarcia tocznego. Zamieszczono wykresy rozkładów obciążenia wewnętrznego w analizowanych łożyskach.
EN
The chosen selected parameters of twin slewing bearings and slewing bearing single-row ball have been presented in the article. The effect of bearing clearance on change of static carrying capacity of both analyzed types has been considered. Diagrams of carrying capacity and friction torque have been created. The finite element method and analytic model of rolling friction has been used to the analysis of presented problems. The diagrams of distribution the internal load in analyzed beadings has been presented.
PL
W artykule przedstawiono analizę wpływu luzu łożyskowego na przebieg charakterystyki nośności statycznej łożyska wieńcowego podwójnego. Wyznaczono w oryginalny sposób charakterystyki momentu tarcia, które zaprezentowano na tle charakterystyk nośności statycznej, odpowiadających wybranym wartościom luzu łożyskowego. Uzyskane wyniki przedstawiono w formie graficznej. Przeprowadzone analizy wykonano z użyciem metody elementów skończonych.
EN
The effect of selected bearing clearances in twin slewing bearing on their static carrying capacity is presented in the paper. Basic parameters of analyzed bearing are presented in the Tab. 1. The finite element method and analytic model of rolling friction has been used to the analysis of presented problems. Obtained results of profile static carrying for selected values of bearing clearance are presented as graph (Fig. 5). It is claimed to be a possibility to single out the range of bearing clearance which optimal profile of static limiting load curves is obtained. The way of determining (modeling) the effect of bearing clearance on the static carrying capacity of twin slewing is based on works [1, 5] and it is introduced in chapter 2. The original method to determining the friction torque for twin slewing bearings is presented (chapter 3) in the article. The calculation which is needed to calculate the maximum contact force on the rolling element has been done using the ADINA program [2, 7]. Profile of carrying capacity and friction torque of twin slewing bearing for selected values of bearing clearances have been presented (Fig. 6). It was thought that the permissible tension force for the fixing bolts should be predicted to the selection of construc-tional bearing clearances. The proposed method of determining of friction torque can be used to the selection of engine power which drive has been transmitted with using slewing bearing. The method presented in the article can be used to the analysis of twin- and other kinds of slewing bearings.
PL
W artykule przedstawiono analizę wpływu luzu między-pierścieniowego i kształtu zakończenia bieżni łożyska wieńcowego podwójnego na jego nośność statyczną. Wykorzystano modelowanie numeryczne za pomocą metody elementów skończonych. Uzyskano oryginalne wyniki, które zaprezentowano w formie graficznej. Określono pewne wytyczne odnośnie luzu między pierścieniowego i kształtu zakończenia bieżni łożyska wieńcowego podwójnego, które mogą być wykorzystane w projektowanych strukturach łożysk wieńcowych podwójnych a także innych typów łożysk wieńcowych.
EN
The effect of selected constructional parameters of twin slewing bearings on their static carrying capacity is presented in the paper. The radial gap between internal and external bearing rings and shape of bearing race profile is analyzed. To the analysis of the problem, the finite element method has been used. The bearing balls are modeled with superelements [7]. Computation was realized in two stages. In the first computation stage the models of contact zone ball - bearing race in elastic-plastic state of material have been developed. The meshing zones of balls and segments of bearing rings are presented in Fig. 1. The method presented in work [8] has been used. In particular models, values of radial gap between bearing rings and shape of edge of bearing race have been changed as in the Tab. 2. To obtain equivalent characteristics of ball - bearing race system, the iteration computations have been used. These characteristics have been used to specify characteristics of elastic truss elements which are being used in superelements. In the second computation stage, the characteristics of the carrying capacity of slewing bearing have been computed. The numerical model of twin slewing bearing presented in Fig. 3 has been used. Exemplary computations have been made for the twin slewing bearing SL023.50.2000 produced by Wuxi Lida Gear Manufacturing Co. (China). Parameters of analyzed bearing are presented in Tab. 1. The results of computation are presented in graphical form in Fig. 4 and Fig. 7. The effect of radial gap between bearing rings on equivalent characteristic of contact zone and on characteristic of bearing carrying capacity has been proved, recommended values of radial gap have been given. The method presented in the article can be used to the analysis of twin- and other kinds of slewing bearings.
EN
The ways of the technological maintenance of the high-quality joint assembly with tightness by the thermal methods are suggested, and the analytical dependences for defining of the separate efficient process variables to ensure the decrease of energy and time (temporary) during the combined thermal method of assembly are also given.
PL
Analiza układu konstrukcja-podłoże gruntowe jest problemem bardzo złożonym, którego rozwiązanie powinno obrazować oddziaływanie tego układu. Szczególną rolę w tej analizie odgrywa odpowiedni opis strefy kontaktu, w której można spodziewać się znaczących względnych przemieszczeń jako, że naprężenia przenoszone są z jednego ciała na drugie. Celem pracy jest synteza wiedzy dostępnej w literaturze dotyczącej specjalnych elementów kontaktowych wykorzystywanych do modelowania strefy kontaktu metodą elementów skończonych.
EN
The analysis of a soil - structure system is a very complex problem and solution of this problem should as much as possible approximate reality. Knowledge of the response of the contact area is essential for the proper simulation of the system. In the mentioned region, significant relative displacements can occur as stresses are transferred from one body to the other. The paper presents the synthesize of interface elements which are used to simulate the behaviour of the contact area from by using the finite element method.
PL
W artykule zaprezentowano analityczno-doświadczalną metodę określania głębokości wpływu ciepła w materiale ostrza narzędzia skrawającego. Analizy prowadzono na przykładzie procesu toczenia dla narzędzia wykonanego ze stali szybkotnącej SW18. Przyjęto model geometryczny oraz szereg założeń formalnych przy których prowadzono rozważania. Wyznaczono zależność określającą głębokość wpływu ciepła, w funkcji czasu działania temperatury na powierzchni natarcia y=f(t).
EN
The analytic-experimental method of assignment of heat influence depth in material of machining tool edge is presented herein. The analysis was made on example of turning operation for tool made from SW18 high-speed steel. Geometric model and a number of formal assumptions were made, at which considerations are performed. Relation defining heat influence depth was assigned in function of temperature action time on attack surface y=f(t).
PL
Obszar między Myszkowem i Mrzygłodem to jeden z kilku rozpoznanych, głębokimi otworami wiertniczymi, obszarów występowania magmatyzmu granitoidowego w regionie krakowsko-częstochowskim. Osłonę skał magmowych stanowią dolnopaleozoiczne serie skał, pierwotnie ilasto-mułowcowe, zmetamorfizowane w warunkach facji zieleńcowej (Ryka, 1973). Podstawą opracowania są własne badania autorki dotyczące wykształcenia, składu mineralnego i chemicznego utworów strefy kontaktu granitoidów mrzygłodzkich i ich metamorficznej osłony. Szczegółowe badania petrologiczne przeprowadzono na podstawie 9-ciu profili otworów wiertniczych. Scharakteryzowano utwory bezpośredniej aureoli kontaktowej, strefy egzo- i endokontaktowej wyróżniając: hornfelsy, łupki hornfelsowe, łupki plamiste, skarny, metasomatyty oraz brekcję intruzyjną. Określono wpływ i zasięg przeobrażeń kontaktowych w osłonie granitoidowej intruzji i stowarzyszonych z nią dajek porfirowych (dacytoidów). Termiczne oddziaływanie intruzji zaznacza się przede wszystkim w bezpośredniej osłonie i odnosi do warunków facji albitowo-epidotowo-hornfelsowej oraz hornblendowo-hornfelsowej metamorfizmu kontaktowego. Większy zasięg miały procesy metamorfizmu kontaktowego związane z udziałem metasomatozy. Doprowadziły one do powszechnych przeobrażeń w tym okruszcowania (Cu-Mo) zarówno skał magmowych jak i ich metamorficznej osłony.
EN
The area between Myszków and Mrzygłód is one of several famous for its granitoid magmatism and well geologically surveyed by numerous test drillings in the investigated Cracow-Częstochowa region. Lower Palaeozoic, claystone-mudstone rocks complex metamorphosed under the conditions of the greenstone facies make the wall rocks of magmatic rocks (Ryka, 1973). Scientific description concerning mineral and chemical composition and formation of rocks in the contact zone of Mrzygłód granitoides and their metamorphic protection based on data from 9 boreholes has been made by the author. Rocks in direct contact aureole have been characterized. Hornfelses, hornfelse schists, fleckschiefers, skarns, metasomatites and intrusive breccia have been ascertained. Influence and extent of contact metamorphoses within the wall rocks of granitoid intrusion and accompanied porphyries (dacitoides) have been defined. Thermal activity of the intrusion connected with the conditions of albite-epidote-hornfelse, hornblende-hornfelse facies of contact metamorphism is observed in nearest wall rocks. Aspects of contact metamorphism, metasomatic processes appeared as metamorphoses, veins and Cu-Mo metallization of magmatic rocks as well as metamorphic protection have been stated in wider extent.
13
Content available remote Semi-empirical model of tire-pavement contact
EN
Mathematical model of the tire - pavement interaction is presented in the paper. One of the main features of the model is easy identification of the parameter values by means typical testing equipment. In the model the contact zone of the tire is divided into the adhesion zone and the slip zone. Influence of the water wedge has been examined. Some typical tire characteristics are shown as a result of application of the proposed model.
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