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1
The influence of plastic deformation on the fatigue strength of crankshafts
100%
Jezierski J. , Tubielewicz K.
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1998
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tom Vol. 69, nr 31
205-212
EN
The purpose of this paper is how really influence nove plastic deformation on the fatigue strength of assembled crankshaft. A result of degree of the deformation of the crankshaft, the fatigue strength of deel wsed for these forgings is different too.
PL
W pracy przebadano wpływ stopnia odkształcenia ramion korby wału korbowego na trwałość zmęczeniową. Wykazano, że istnieje różny stopień odkształcenia ramion korby w czasie kucia, co w istotny sposób wpływa na zróżnicowanie wartości zmęczeniowej w różnych miejscach korby.
2
Symmetrization of dimensional tolerances
100%
Jezierski J. , Tubielewicz K.
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2000
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tom Vol. 76, nr 35
193-6
EN
The purpose of this paper is to show how symmetrization of dimensional tolerances may simplify their synthesis and analysis. The basic rules of such tolerancing applicable in machine tools design are presented.
3
Vector analysis of resultant tolerance in spatial dimension chains
100%
Jezierski J. , Tubielewicz K.
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1999
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tom Vol. 72, nr 33
265-273
EN
The paper presents the description of new method calculation of the geometric tolerances in the spatial dimensions chains. The purpose of this paper is to show how symmetrization of dimensional tolerances may simplify their synthesis and analysis in the spatial dimensions chains. We generalize method of symmetrization of dimensions to the case of nonflat chains and the main idea consists in the spherical structure of the deviations.
PL
W pracy przedstawiono nową metodę obliczeń tolerancji wynikowej w przestrzennych łańcuchach wymiarowych. W metodzie zastosowano symetryzację wymiarów składowych łańcucha, przez co obliczanie tolerancji wynikowej znacznie się upraszcza, zarówno w analizie jak i w syntezie przestrzennych łańcuchów wymiarowych. Metoda polega na uogólnieniu symetryzacji i sumowaniu wektorów z odchyleniami o strukturze kulistej.
4
Analytical results for the diameter reduction coefficient in the longitudinal rolling process
100%
Jezierski J. , Tubielewicz K.
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1999
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tom Vol. 72, nr 33
274-282
EN
The paper presents the description of a method of forming stepped shafts by longitudinal cold rolling. An inequality determining the limiting value of the formed-shaft diameter reduction during longitudinal rolling. The aim of the present paper is to determine the diameter reduction coefficient as a function of the parameters profile geometry ofundeformable roller. The method consists in cold working of shafts if symmetric cross- section by small deformations using multiple longitudinal passages. As a consequence, high roll pressures are avoided and formed shaft is not liable to breaking
PL
W pracy przedstawiono opis metody nagniatania wzdłużnego na zimno wałków stopniowanych. Wprowadzona nierówność na współczynnik indukcji średnic podczas nagniatania wzdłużnego limituje wartość indukcji. W pracy pokazano zależność na współczynnik redukcji średnic w funkcji parametrów geometrycznych nieodkształcalnej rolki. Metoda ma zastosowanie do obróbki na zimno wałków o symetrycznych przekrojach małymi deformacjami przy dużej liczbie przesuwów wzdłużnych. W konsekwencji naciski są małe i kształtowany wałek nie doznaje pęknięć jakie występuje przy dużych naciskach rolek.
5
Zastosowanie wektorów kulistych do obliczania przestrzennej tolerancji wynikowej.
100%
Jezierski J. , Sieczka P.
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2000
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tom Vol. 78, nr 36
119-122
PL
W pracy przedstawiono metodę (sposób) obliczania przestrzennej tolerancji wynikowej przy pozycjonowaniu ruchomych zespołów maszynowych (wrzecion obrabiarek i orientacji chwytaków manipulatorów o ruchach przestrzennych). Dla obliczeń wykorzystano symetryzację wymiarów składowych łańcucha wymiarowego i sumowanie wektorowe symetrycznych odchyłek o strukturze kulistej).
EN
In this paper we present a new method describing maximal space of tolerance in vector analysis of spatial mechanical system. We generalize method of summarization of dimensions to the case of spatial mechanical systems and calculate the spherical deviations. This method can be applied to the analysis tolerance and calculation of the position error.
6
Content available remote Aspekty technologiczno-montażowe zakończeń wkrętów samoformujących gwint metryczny.
100%
Jezierski J. , Kowalik M.
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2001
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tom nr 2
60-62
7
Content available remote Character of diphase stream force in powder injection technique
100%
Jezierski J. , Szajnar J.
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2007
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tom Vol. 20, nr 1-2
455-458
EN
Purpose: The method of pneumatic injection of powdered reagents into liquid alloys in some moment of melting process is known since many years. Mostly it is carrying out with use of submerged lance but in some cases that technique is difficult or impossible at all to use. This is the reason for making investigations in the filed of powders injection with non-submerged lance. Design/methodology/approach: The main experimental method was measurement and recording of time-changing diphase stream force value with use of dedicated laboratory stand. The recorded data made possible to show character of force in form of graphs and calulation of stream parameters. The last step was formulating of statistical equations joining all important parameters of the process. Findings: In the course of the work was found a diphase stream force character (especially interesting are start and end point of injection). The influence of main pneumatic parameters on the force value was analyzed too. Research limitations/implications: The future experiments will be conducted with use to Fluent 6.2 program for checking the results in computer simulations. The limitation is number of values being analyzed in experimental plan. Practical implications: The invented lance can be used for powders pneumatic injection but only for small its quantities (e.g. microalloying) because non-immersed lance should be used with low stream concentration. The usage of that lance can increase liquid alloy heat losses (not introducing carrier gas into liquid) and lance consumption (non-immersed in liquid bath). Originality/value: The problem of stream force in powder injection process is in Poland only analyzed by Department of Foundry and nobody (in author's opinion) was analyzed it with connection in powder injection. Originality of the researches is a computer recording and analyzing of the diphase stream force. The results should interest every who wants to learn more about pneumatic powder injection.
8
Content available remote Relationship between stream forces and parameters of the powder injection into metal bath
100%
Jezierski J. , Szajnar J.
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2007
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tom Vol. 28, nr 4
238-245
EN
Purpose: The pneumatic method of introduction of various powders into ladle or metallurgical furnaces is use because of its many advantages. There are no problems with use of injection lances in electric arc furnaces but in inductive furnaces or ladles, especially big ones the problem of metal flowing out of it may appear. This is the reason why the authors have maiden some experiments which results are presented in the article. Design/methodology/approach: The new lance with a flange was invented and used in powdered material injections experiments. The experimental plan was prepared that contain the most important parameters of pneumatic process. A statistical analysis was made to connect the results of the injection process with its parameters. Findings: The main conclusion is the influence of carrier gas pressure, lance inside diameter and mass concentration of diphase stream on the obtained results. The next one is that changing of the lance geometry could effectively improve the technological parameters of the process and that the new design of the injection lance is prepared properly. Research limitations/implications: The limitations of the results is that the experiments were only the "cold model" ones, without presence of molten metal. The only liquid medium used was water for experiments with stream distance measurement. The nest experiments are planned with injection of powder into laboratory induction furnaces for checking the obtained results. Practical implications: According to the authors, the new lance can be used for introducing a small quantity of the powdered material like modifiers or something like that. Originality/value: The approach to the problem of diphase stream forces and distance of stream in liquid is according to authors' knowledge a new one. The lance with flange proposed for those usage is not present in literature and is an originality too. The paper could be interesting for all interested in problems of melting processes improving.
9
Content available remote Wybrane zagadnienia montażowe składanych wałów korbowych.
100%
Jezierski J. , Siemiątkowski Z.
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1998
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tom nr 1
33-34
10
Content available remote Properties of cast iron modifying with use of new inoculants
100%
Jezierski J. , Bartocha D.
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2007
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tom Vol. 22, nr 1
25-28
EN
Purpose: Modification of various alloys is a well known process for improvement its properties by changing of microstructure character. In foundry technology it is connected mostly to cast iron production where many inoculants is used for obtaining some results like grain refinement, graphite inclusions proper distribution etc. Those changes caused that produced alloy have a much better properties especially mechanical ones. Design/methodology/approach: In the paper were presented some results of the experiments made for checking quality of the two new on Polish foundry market complex inoculants. One of them is a "graphite" inoculant (about 50% C) and second is Ba-Ca combination based inoclulant. The experiments contained metallographic and quantitative metallographic analysis and wedge test bars analysis. Findings: These experiments proved a good quality of inoculants in the field of microstructure improvement (graphite size reduction) and a hard spot defects liquidation. Research limitations/implications: The next experiments are planned for checking the mechanical properties of the produced alloys. Practical implications: The inoculants being analysed are used in several Polish foundries now because of author's good results. Originality/value: There were the first experiments with these materials although the methods of investigations are not novel or original. The results have a very big importance not only from scientific but from practical point of view too.
11
Content available remote Multiquery optimization methods in data warehouse and OLAP systems
100%
Królikowski Z. , Jezierski J.
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1998
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tom Vol. 23, No. 1
35-47
EN
Conventional database management systems (DBMS) do not adequately meet the requirements of non-traditional, advanced applications, for example in data warehouse and on-line analytical processing (OLAP) systems. In order to support these applications, the functionality of conventional DBMS is being extended in several ways, between others by introducing some extensions to conventional query processing techniques. Traditional query optimization techniques are not sufficient, when used for queries in advanced database applications. In this paper we analyze, multiquery optimization problem in data warehouse and OLAP systems. We present workable example that shows opportunities and benefits of using of multiquery optimization approach in such systems. Finally, we introduce two global alternative multiquery optimization methods that can be used in advanced data base systems (DBS). Results achieved from a simulation experiment show that these methods can be very useful in advanced database environment.
12
Content available remote Powder pneumatic injection as a tool for wastes utilization
100%
Jezierski J. , Janerka K.
|
2009
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tom Vol. 36, nr 2
118-124
EN
Purpose: Metallurgical process generates many solid, gaseous and liquid wastes. Nowadays when environmental protection is one of the most important problems and when pollution limits are very tight as well, problem of the metallurgical wastes is a strategic one. Design/methodology/approach: In present days the metallurgical and foundry plant have to utilize their own wastes, especially these which are the most dangerous and toxic or have to render harm of its and transfer to another industry branch for further utilization. Nowadays the issue of wastes management has the place both in industrial practice and scientific field too. The presented work is a result of such an approach, where a cooperation between scientific and industrial partners gives good economical and ecological results. Findings: One of the very efficient method of utilization of furnace dusts from any melting furnace or the finest fractions of charging materials is pneumatic powder injection directly into molten metal bath.The method is pretty easy and cost effective in various conditions and its flexibility allows to implement it in almost every foundry or metallurgical plant. Research limitations/implications: Further experiments should be carried out to solve some additional problems appearing during powder injection processes to make them more efficient in various technological conditions. Practical implications: Nowadays in Poland operate more than ten industrial stands for powdered carburizers injection, installation of furnace dust injection back to the melting furnace or pneumatic inoculation of alloys (mostly in cast iron foundries). Originality/value: The paper presents a few modern solutions for recycling and utilization of furnace dusts (in cupolas and EAF’s) and pneumatic carburization with use of powdered carburizers which are very often in form of grinded graphite electrodes wastes. All of the mentioned results and method had been developed in Department of Foundry and some of the designs had been previously patented.
13
Content available remote Montaż i analiza wymiarowa zespołu tłok-korbowód w silniku spalinowym
80%
Jezierski J. , Kowalik M. , Siemiątkowski Z.
|
2008
|
tom nr 3
28-30
EN
The volume of combustion chamber consists of head and cylinder space. The distribution of volumes in the cylinder depends on accuracy of dimensions, determined the production process and precision of the piston - rod connecting during assembling. In this paper presents analyses tolerance of the piston - rod connecting and it assembly. The scheme of aim dimensions was elaborated for calculation height of volumes in the cylinder space.
14
Content available remote Quality and properties of the cast iron produced on the steel scrap base
80%
Janerka K. , Jezierski J. , Szajnar J.
|
2012
|
tom Vol. 53, nr 2
92-101
EN
Purpose: The goal of the article is to show the issue of the cast iron melting on the steel scrap base only (with no pig iron in charge). The particular interest was focused on the charging material chemical composition influence on the particular elements content in produced cast iron and its quality, too. Design/methodology/approach: The grey cast iron melting on the steel scrap base and recarburizers (anthracite, natural and synthetic graphite, petroleum coke) was conducted to achieve the goals of the experiments. The chemical composition, mechanical properties and microstructure was tested for each melt. Melting was conducted in inductive furnace of 20kg capacity. Findings: The experiments drawn to the conclusions that cast iron melted on the steel scrap base contains less impurities (sulfur and phosphorus) than this melted on the pig iron base. During the results further analysis the relationship between carburizer grade and both mechanical properties and microstructure of the produced cast iron was proved (microstructure heredity). Research limitations/implications: To finally prove the hypothesis regarding the microstructure heredity given in the article, further researches should be carried out with the anthracite use as a carburizer. Practical implications: The results achieved suggest that when anthracite is used as a carburizer it is possible to increase mechanical properties with no necessity of changing other process parameters. Regarding the fact that the anthracite is relatively cheap carburizer it may cause in consequence less expensive production along with the cast iron quality parameters increase. Originality/value: The issue of the materials microstructure heredity is not widely described in the literature and the experiments results presented in the article allow to create the hypothesis that this phenomenon is present in the metal alloys.
15
Calculation pressures and the contact field in the contact zone of a burnishing roller and worked material
80%
Tubielewicz K. , Jezierski J. , Znorko D. A.
|
2000
|
tom Vol. 76, nr 35
93-99
EN
Gives an approximate solution for mean pressures and the contact field between the tool and the workpiece. Mean pressures in the burnishing roll contact zone have been calculated for two worked materials with different yield point wakes. The computation results are given in the from of diagrams of pressures as a function of roll clamp forces.
16
Content available remote Określenie głębokości osadzania żeber radiatora za pomocą symulacji numerycznej
80%
Jezierski J. , Kowalik M. , Trzepieciński T.
|
2009
|
tom z. 77 [269]
19-25
PL
W pracy zaprezentowano wyniki badań doświadczalnych oraz symulacji numerycznej procesu osadzania żebra radiatora. Do symulacji numerycznej użyto pakietu Msc MARC/Mentat 2005. Porównano zastosowaną technologię osadzania żeber w płycie radiatora poprzez wgłębianie stempli na krawędziach frezowanego kanału z wynikami symulacji numerycznej. Miarą jakości złącza jest powierzchnia przylegania żebra w złączu z powierzchnią rowka w płycie radiatora. W celu sprawdzenia tego parametru przecięto radiator i wykonano zgłady do zdjęć metalograficznych.
EN
In this paper the results of experimental researches and numerical simulation of the heat sink fin fixed were presented. The Msc MARC/Mentat 2005 package was used to numerical simulation. The aim of the article is to compare application mount technology of fins in heat sink plate with the results of numerical simulation. The measure of the joint qualities is the adherent surface of the fin in joint with the groove surface in heat sink plate. To verify this parameter the heat sink was cross-cutted and the metallographic specimen were performed.
17
Transport pneumatyczny w procesach wdmuchiwania proszków do ośrodków ciekłych
80%
Janerka K. , Szlumczyk H. , Jezierski J.
|
2002
|
tom nr 2 (8)
49-51
PL
Transport pneumatyczny najczęściej kojarzony jest z przemieszczaniem materiałów sypkich na określone odległości. Realizowane jest to w układach składających się z urządzenia nadawczego (dozownik, podajnik) zasilanego sprężonym powietrzem lub pracującego na podciśnieniu, przewodów transportowych i urządzenia odbiorczego (zbiornik z odpowiednimi filtrami). Coraz częściej we współczesnym przemyśle spotyka się nowe aplikacje transportu pneumatycznego [1], wykorzystując jego hermetyczność, dokładność dozowania i możliwość automatyzacji. Jedno z takich zastosowań to wdmuchiwanie sproszkowanych materiałów do ciekłego metalu.
18
Modelowanie fizyczne procesu wdmuchiwania strumienia jedno- i dwufazowego do ośrodka ciekłego
80%
Janerka K. , Gawroński J. , Szlumczyk H. , Jezierski J.
|
2002
|
tom nr 3 (9)
64-66
19
Content available remote Analiza tolerancji komory spalania w cylindrze w chwili wtrysku paliwa
80%
Jezierski J. , Kowalik M. , Siemiątkowski Z.
|
2007
|
tom R. 46, nr SC1
124-130
EN
Every contemporary internal combustion engine has been created in the result of work of many generations of design engineers and the need of perfecting the engines has stimulated the development of design, essembling and calculation methods. The volume V of the cylinder combustion chamber depends on toleranced dimensions of the crankshaft system elements, and also on the injection advance angle α. The geometrical analysis of crankshaft system, presented in this article, gives a basis for examining processes in individual cylinders. It also makes it possible to evaluate thermodynamics of the whole engine. If we have the function for the analysis of combustion chamber tolerances in individual cylinders, calculate volume of tolerances Tv is easy.
20
Content available remote Operacje montażu i analiza tolerancji układu korbowego silnika spalinowego.
80%
Jezierski J. , Kowalik M. , Siemiątkowski Z.
|
2006
|
tom nr 3
54-57
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