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1
Content available Innovative correlation relating the destruction of graphite flakes to the morphology characteristics of minerals
Wang Nailing, Xu Xinyang, Jiang Yanxin, Yuan Zhitao, Lu Jiwei, Li Lixia, Meng Qingyou
Physicochemical Problems of Mineral Processing
|
2024
|
Vol. 60, iss. 1
art. no. 183655
EN
The morphology characteristics (sphericity, roundness, and surface roughness) affecting the destruction of gangue minerals on graphite flakes during the grinding process were systematically analyzed. Coupled with MS and SEM, sphericity analysis showed that graphite was flaky, which was similar to muscovite but different from granulous quartz and albite, and the roundness of the four minerals from high to low was graphite, quartz, albite, and muscovite. AFM analysis showed that the surface roughness of graphite and muscovite was very low compared to that of quartz and albite (higher than quartz). The size and crystal integrity of graphite flakes were both destroyed by gangues during the grinding process, and the destruction of quartz and albite was serious compared to that of muscovite. Sphericity dominantly affected the destruction: the larger the sphericity, the more serious the destruction, which was also negatively related to roundness but positively related to surface roughness.
2
Content available The effect of shape and roughness on flotation and aggregation of quartz particles
Guven Onur
Physicochemical Problems of Mineral Processing
|
2022
|
Vol. 58, iss. 6
art. no. 154021
EN
A combination of grinding and abrasion processes was applied to control the shape and roughness of quartz particles to investigate their roles in flotation recoveries and aggregation rates at different collector concentrations. The results showed that while the roundness values (Ro) of quartz particles varied in the range of 0.56-0.58 (Ro) at 480 and 1920 sec grinding, the roughness values of particles varied between 3.12-4.02 μm at 60 and 240 min abrasion. The flotation and aggregation tests showed while the flotation recovery increased from 31.3 % to 34.2 % in reverse proportion to their roundness values at 1x10-6 M DAH concentrations, a similar increasing trend from 34.1% to 38.1 % as a function of their roughness value from 3.12 μm to 4.02 μm. On the other hand, in the case of aggregation tests, while the turbidity values decreased from 40.6 NTU to 32.1 NTU at 1x10-6 M DAH concentrations for rounder particles, it was found as 36.2 NTU to 31.8 NTU for rougher ones. The overall results of this study indicated that tuning the morphology of quartz particles may be used to adjust both the flotation and aggregation rate of particles.
3
Content available Morphological changes of glass bead particles upon an abrasive blasting as characterized by settling and flotation experiments
Behzad Vaziri Hassas, Güven Onur, Baştürkcü Esra, Çelik Mehmet S.
Physicochemical Problems of Mineral Processing
|
2021
|
Vol. 57, iss. 2
157--168
EN
The recent developments in mineral processing led researchers to look for alternative methods and propose new mechanisms for enhancing the efficiency of relatively costly processes (e.g., flotation, aggregation), where especially dealing with fine particles. Finer the particles, the higher the role of their surface on their behavior and properties. The importance of particle morphology becomes even clearer when particle-particle and particle-bubble interactions are considered. In this study, the effect of particle shape “roundness” on the surface wettability and flotation response was investigated upon producing fine particles with the “abrasion blasting” method. In order to provide a fundamental perspective, adsorption measurements were also carried out along with the flotation experiments under the same conditions. In addition to these, zeta potential measurements were also carried out with both spherical and blasted particles as a function of collector concentration. The results suggested that the roundness of particles decreased up to a certain nozzle pressure value, which was followed by higher adsorption degrees and consequently higher flotation recoveries. Additionally, settling rate tests were also performed with very fine material to show the effect of particle morphology on particle-particle interactions. The results showed that while lower settling rate values were obtained for spherical ones, higher values were obtained in the case of the ground and blasted samples in the presence of DI water. It was concluded from this study that the “Abrasive blasting method” could be an effective alternative for tuning the surface morphology of particles and their wettability, which in turn can affect the particleparticle interactions in the system.
4
Content available remote Model matematyczny oceny wpływu odchyłki okrągłości i falistości powierzchni bieżni łożysk tocznych na poziom generowanych drgań
Zmarzły Paweł
Mechanik
|
2019
|
R. 92, nr 1
35--37
PL
W artykule zaprezentowano modele matematyczne, opisujące poziom drgań generowanych przez kulkowe łożyska toczne typu 6304-2z w zależności od wartości odchyłki okrągłości i falistości bieżni wewnętrznej oraz zewnętrznej. Modele pozwalają na ustalenie, który typ odchyłek kształtu ma dominujący wpływ na poziom drgań generowanych w określonych zakresach częstotliwości.
EN
The article presents mathematical models allowing to describe the level of vibration generated by ball bearings 6304-2z type depending on the value of roughness and waviness deviations of inner and outer bearings races. This models will allow to estimate what type of shape deviations have dominant influence on the vibration level generated in specific frequency ranges.
5
Content available Measurement System for Assesment of Motor Cylinder Tolerances and Roundness
Jermak C. J., Dereżyński J., Rucki M.
Metrology and Measurement Systems
|
2018
|
Vol. 25, nr 1
103--114
EN
The paper describes the concept of a novel measurement system designed for quick and inexpensive measurement of tolerances and assessment of roundness, especially suitable for the motor industry. The structure of measurement system and its algorithm of measurement data analysis are described in detail. The system underwent tests with the setting (master) rings of known tolerances and out-of-roundness. The results were compared with those obtained from the reference device PIK-2. The tested system exhibited a very good accuracy and proved to be a good measurement tool. It was implemented in the industrial enterprise.
6
Content available remote Wpływ prędkości obrotowej stolika pomiarowego na dokładność pomiaru odchyłki okrągłości za pomocą pneumatycznego przetwornika długości
Jakubowicz M.
Mechanik
|
2016
|
R. 89, nr 11
1648--1649
PL
Przedstawione w artykule badania eksperymentalne mają na celu ustalenie, jaki wpływ na wynik pomiaru odchyłki okrągłości uzyskanych pneumatyczną metodą pomiarową ma zmiana prędkości obrotowej stolika pomiarowego. W pomiarach wykorzystano przetworniki wyposażone w klasyczne dysze pomiarowe o przekroju kołowym; pomiary wykonano za pomocą przetwornika wyposażonego w dyszę szczelinową.
EN
The article presents in experimental studies is to determine the impact on the result obtained roundness deviation pneumatic measuring method is to change the speed of the measuring table. In the measurements used gauge with classical measuring nozzles of circular hole and measurements were used by the air gauge with a slotted nozzle.
7
Content available Theoretical And Practical Investigations Of V-Block Waviness Measurement Of Cylindrical Parts
Adamczak S., Zmarzły P., Janecki D.
Metrology and Measurement Systems
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2015
|
Vol. 22, nr 2
181--192
EN
The paper relates to the problem of adaptation of V-block methods to waviness measurements of cylindrical surfaces. It presents the fundamentals of V-block methods and the principle of their application. The V-block methods can be successfully used to measure the roundness and waviness deviations of large cylinders used in paper industry, shipping industry, or in metallurgy. The concept of adaptation of the V-block method to waviness measurements of cylindrical surfaces was verified using computer simulations and experimental work. The computer simulation was carried out in order to check whether the proposed mathematical model and V-block method parameters are correct. Based on the simulation results, a model of measuring device ROL-2 for V-block waviness measurements was developed. Next, experimental research was carried out consisting in evaluation of waviness deviation, initially using a standard non-reference measuring device, and then using the tested device based on the V-block method. Finally, accuracy of the V-block experimental method was calculated.
8
Content available Separation Of Non-Periodic And Periodic 2D Profile Features Using B-Spline Functions
Janecki D., Cedro L., Zwierzchowski J.
Metrology and Measurement Systems
|
2015
|
Vol. 22, nr 2
289--302
EN
The form, waviness and roughness components of a measured profile are separated by means of digital filters. The aim of analysis was to develop an algorithm for one-dimensional filtering of profiles using approximation by means of B-splines. The theory of B-spline functions introduced by Schoenberg and extended by Unser et al. was used. Unlike the spline filter proposed by Krystek, which is described in ISO standards, the algorithm does not take into account the bending energy of a filtered profile in the functional whose minimization is the principle of the filter. Appropriate smoothness of a filtered profile is achieved by selecting an appropriate distance between nodes of the spline function. In this paper, we determine the Fourier transforms of the filter impulse response at different impulse positions, with respect to the nodes. We show that the filter cutoff length is equal to half of the node-to-node distance. The inclination of the filter frequency characteristic in the transition band can be adjusted by selecting an appropriate degree of the B-spline function. The paper includes examples of separation of 2D roughness, as well as separation of form and waviness of roundness profiles.
9
Content available Parametry kształtu ziaren gruntowych oraz analityczne sposoby ich wyznaczania
Szerakowska S.
Przegląd Geologiczny
|
2014
|
Vol. 62, nr 10/2
704--714
EN
Particle shape is a major factor conditioning behavior of soil, which in natural conditions is very diverse and complex. For the generally accepted characteristics describing the shape of granule was sphericity, angularity and surface microstructure. Due to the lack of specified by standards definition of shape and its properties and methods of their determination, over the years developed various definitions and methods of determination elaborated by many authors. The most popular parameters were sphericity and angularity, which results in a number of possible definitions of these parameters. Due to the complicated character of the microstructure of the granule surface, this parameter wasn't defined so many and is often overlooked when determining the shape of the aggregate. On the basis of literature data atempted to compilation definition and analythical methods of determining the characteristics of the shape of the granules. In further part of work drew attention to the subject of the shape of the granules and methods of its description in the standards EN ISO 14688-1:2006 force in mostcountries of the European Union and ASTM D 2488-00 used in the United States.
10
Content available remote Wpływ odchyłki kształtu na wyniki pomiarów elementów walcowych
Kowalski M., Sładek J.
Mechanik
|
2014
|
R. 87, nr 8-9CD1
162-170
PL
W opracowaniu przedstawiono problematykę klasyfikacji i pomiaru elementów walcowych z odchyłkami kształtu. Podano wstępny opis wymiaru lokalnego wynikającego ze zmian w danym przekroju oraz wzdłuż tworzącej. W zakresie metodyki badań opisano pokrótce sposób otrzymywania próbek walcowych z elementarnymi odchyłkami kształtu. Próbki były mierzone za pomocą okrągłościomierza i na WMP. Wyniki pomiarów pozwoliły na wstępną ocenę wpływu liczby pomiarów oraz liczby przekrojów pomiarowych na rezultaty badań.
EN
The paper presents the theme of both classification and measurement of cylindrical elements with shape deviations. Moreover the preliminary description of local size comming shape changes in given cross-section and also along generating line has been given. In case of reaserch methodology has been briefly described the method of obtaining of cylindrical samples with elementary shape deviations. Samples have been measured with the use of both roundness gauge and also CMM. Measurement results allowed to carry on preliminary evaluation of the impact of both measurements and cross section numbers on measurement results.
11
Content available remote Aplikacja bezodniesieniowych metod oceny odchyłki kształtu w zastosowaniach medycznych
Ryniewicz A., Kowalski M.
Mechanik
|
2014
|
R. 87, nr 8-9CD1
337-348
PL
Ocena odchyłek kształtu powierzchni ślizgowych biołożysk ma szczególne znaczenie przy analizie tribologicznej stawów. W pracy przedstawiono pomiary odchyłek kształtu okrągłości i sferyczności głowy kości udowych drobiowych i wieprzowych z zastosowaniem bezodniesieniowych metod pomiarowych. Badania przeprowadzono z wykorzystaniem kształtografu Talycenta oraz ramienia pomiarowego wyposażonego w laserową głowicę pomiarową. Określono wartości odchyłek okrągłości w wybranych przekrojach oraz sferyczności w zależności od położenia osi funkcjonalnej stawu.
EN
Assessment of biobearings sliding surfaces shape deviations is of particular importance during the tribological joints analyzes. This paper presents measurements of roundness and sphericity deviations of poultry and pig femoral bone head using radial methods. The study was conducted using Talycenta machine and measuring arm equipped with a laser scanning head. Roundness values were specified in the selected sections and sphericity were evaluated depending on the position of the functional axis of the joint.
12
Content available New trends in design of instruments for measurements of roundness and cylindricity
Stępień K.
Advanced Technologies in Mechanics
|
2014
|
Vol. 1, no. 1 (1)
19--27
EN
The paper deals with modern systems for roundness and cylindricity measurements. It gives the classification of methods for roundness and cylindricity measurement and it describes more precisely the radial method. Fundamental part of the paper is presentation of measuring abilities of Talyrond 365. In the summary a brief comparison between of and new systems for cylindricity measurements are given.
13
Content available remote Model matematyczny odniesieniowych pomiarów odchyłek kształtu i falistości elementów okrągłych
Adamczak S., Zmarzły P., Stępień K.
Mechanik
|
2013
|
R. 86, nr 7
518--521
PL
Przedstawiono model matematyczny odniesieniowych metod pomiaru odchyłki okrągłości oraz zaproponowano jego zastosowanie do pomiarów falistości powierzchni. W ramach badań przeprowadzono symulację kombinacji kątów α i β , tj. parametrów metody odniesieniowej w zakresie 16 ÷ 50 fal/obwód, co obrazuje falistość powierzchni.
EN
The paper presents a mathematical model of the V-block roundness measurement and a principle of its application to measurements of surface waviness. The research involved a simulation of the combination of angles α and β , i.e. parameters of the V-block method, for 16 ÷ 50 UPR, which corresponds to waviness components.
14
Content available Wpływ elementu odniesienia na wynik pomiaru okręgu na CMM
Gapiński B., Kołodziej A., Grzelka M.
Pomiary Automatyka Robotyka
|
2012
|
R. 16, nr 4
78-81
PL
Współrzędnościowa technika pomiarowa rozwija się dynamicznie od wielu lat. Dziś jest reprezentowana przez szereg urządzeń, takich jak współrzędnościowe maszyny pomiarowe czy skanery optyczne. Przy pomocy tych urządzeń dokonuje się pomiarów współrzędnych punktów reprezentujących mierzony obiekt. Następnie, stosując odpowiednie oprogramowanie komputerowe, wykonywane są obliczenia pozwalające na ocenę zmierzonych obiektów. Wśród najczęściej kontrolowanych elementów są otwory i wałki reprezentowane przez pojedynczy przekrój, czyli okrąg. W zależności od przyjętej strategii możliwy jest pomiar impulsowy lub ciągły (skaningowy). Następnym krokiem jest dobór elementu odniesienia, który pozwala na obliczenie parametrów elementu integralnego skojarzonego, jakim w rozpatrywanym przypadku jest okrąg zastępczy, oraz elementu pochodnego zastępczego, jakim w tym przypadku jest środek okręgu. Możliwe jest również wyznaczenie odchyłki kształtu na podstawie punktów pomiarowych oraz okręgu zastępczego. Zgodnie z normą ISO/TS 12181, do oceny parametrów okręgu możliwe jest stosowanie jednego z czterech elementów odniesienia. Możliwość zastosowania różnych elementów zastępczych oraz różnej liczby punktów pomiarowych wpływa na uzyskane wyniki pomiaru. W artykule przedstawiono wpływ strategii pomiarowej na uzyskiwane rezultaty, a także zalecenia wpływające na uzyskiwanie poprawnych metrologicznie rezultatów.
EN
Coordinate measuring technique has been developed strongly for many years. Today this technique is represented by a number of devices, such as coordinate measuring machines and optical scanners. Using these devices coordinates of points that represent the object are measured. Then, in order to valuate geometry of the measured object, calculations with appropriate computer software are performed. Some of the most often controlled elements are holes and shafts, represented by a single section or a circle. Depending on the adopted strategy there are possible pulsing or continuous (scanning) measurement. The next step is to select a reference element, which allows to calculate parameters of an integral associated element. In considered case, this is a circle component replacement. What is more, the derivative component replacement (in this case it is the centre of the circle) is determined. On the basis of both measurement points and the circle replacement, shape deviations might be evaluated. In accordance with ISO/TS 12181 to estimate parameters of the circle it is recommended to use one of four reference elements. The opportunity of applying alternative reference elements and different number of points affect measurement results. The aim of this paper is to present the influence of measurement strategy on the obtained results, and recommendations about how to get metrologically correct measurement results.
15
Content available remote Bexperimental Investigation into Tribopairs Journal Sleeve of Journal Bearing
Michalak R., Wójcicki R.
Machine Dynamics Research
|
2012
|
Vol. 36, No. 3
53-64
EN
This paper presents the results of plain journal bearings with the operating surface covered by white metal bearing alloys: tin and lead operating with steel journal and bush poured by bronze and nitrosulfonized. It also presents preliminary studies of bearing set: hardened steel journal covered with a layer of nano-composite nc-WC/aC: H - bush of bearing metal as lead alloy. The effect of wear on the tribological characteristics of the bearing was investigated. During the tests a continuous identification of friction conditions was monitored in the bearing. The wear was determined by a method based on the measurement of the roundness of bearing operating surface as well as on the traditional way by weight.
16
Content available The models for the comparison of roundness profiles
Tichá S., Adamczak S.
Journal of Automation Mobile Robotics and Intelligent Systems
|
2012
|
Vol. 6, No. 3
27-29
EN
Roundness is one of the mostly frequently observed geometrical deviations. A profile of a machine part consisting of simple harmonic courses or their sums depends on a number of factors. Modeling of geometrical deviations requires applying the Fourier to extend each periodical function into an infinite series of harmonic components. Using of harmonic analysis we are able to determine the values of amplitudes of single components and their phase shifts. These parameters can be used for example for comparison of roundness profiles by means of correlation coefficients. The obtained correlation coefficients are concrete parameters, on the basis of which it is possible to determine the degree of conformity and unity between the compared profiles. The comparison of evaluated roundness profiles can be represented as mathematical statistical models. In these models is detected sequence of single steps, which are necessary for determination of required correlation coefficients [1, 2] .
17
Content available Statistical validation of the method for measuring radius variations of components on the machine tool
Adamczak S., Janusiewicz A., Makieła W., Stępień K.
Metrology and Measurement Systems
|
2011
|
Vol. 18, nr 1
35-46
EN
This paper deals with the experimental validation of the suitability of the method for measuring radial variations of components on the process tool. The tests were conducted using a computerized PSA6, which was compared to a Talyrond 73. The results of measurement of roundness deviations as well as roundness profiles were analyzed for a sample of 70 shafts. The roundness deviations were assessed by determining the experimental errors, while the profiles obtained with the tested device were compared to those registered by the reference device using three correlation coefficients.
18
Content available remote Podejmowanie decyzji o postaci geometrycznej podczas projektowania części maszyn
Kołodziej A., Dudziak M.
Mechanik
|
2010
|
R. 83, nr 1/S
94-101
PL
Wykazano potrzebę jednoznacznego oraz spójnego języka komunikacji pomiędzy konstruktorem a inżynierami: wytwarzania, pomiaru i eksploatacji podczas projektowania i opisu geometrycznych cech konstrukcji. Na przykładzie specyfikacji tolerancji okrągłości średnicy zewnętrznej sworzni wykazano potrzebę doskonalenia wymiarowania i tolerowania z uwzględnieniem wytycznych co do metody i strategii pomiaru oraz zdefiniowania poszczególnych jego czynności.
EN
There was analysed technical record in technical documentation of axialsymmetrical elements applied in aeronautical engineering. On the basis of construction of pins there was pointed out that measurement and verification of geometrical shape quality of elements, which are manufactured according to criterion of form deviation - roundness, have not a formal definition and documentation for applied measurement methodology. There was showed that during conducting some measuring procedures of roundness deviations there are taken subjective criteria for measurement and estimation of achieved results. On the basis of selected examples of measurement of geometrical form of diameter and roundness deviations there were given reasons of discrepant results obtaining, which were caused by variable parameters of measurement.
19
Content available Method of Evaluation of Roundness Profiles of Machine Parts Using The Wavelet Analysis
Makieła W., Stępień K., Stępień K.
Pomiary Automatyka Kontrola
|
2008
|
R. 54, nr 5
244-247
EN
In hitherto practice, roundness and cylindricity profiles have been evaluated using the Fourier transform. In numerous metrological branches, however, concerned with the evaluation of variable signals, the wavelet analysis is applied. Efforts have been undertaken to apply this method to the evaluation of geometrical surface structure. This paper describes the application of the Haar expansion to the approximation of roundness profiles and to the presentation of the concept of comparison of two roundness profiles decomposed by the wavelet method. The examples presented in the paper were used for preliminary evaluation of the proposed concept.
PL
W dotychczasowej praktyce w ocenie zarysów struktury geometrycznej powierzchni szeroko wykorzystuje się zasadę transformacji Fouriera. Znalazło to szczególne zastosowanie w analizie pomiarów okrągłości i walcowości. Z tego względu, że w wielu dziedzinach metrologii do oceny zarysów zmiennych stosuje się z dużym powodzeniem transformacjcę falkową, podjęto prace nad aplikacją, tej metody do oceny zarysów struktury geometrycznej powierzchni. Niniejszy referat poświcęony jest zastosowaniu rozwinięcia Haara do aproksymacji sygnałów zarysu nierówności powierzchni części maszyn oraz prezentacji koncepcji porównywania zarysów chropowatości powierzchni, które zostaly poddane dekompozycji falkowej. Przedstawione w referacie przykłady posłużyły do wstępnej oceny zaproponowanej metody.
20
Content available Assessing the accuracy of a computerized roundness profile measuring instrument used under industrial conditions
Adamczak S., Janusiewicz A.
Pomiary Automatyka Kontrola
|
2008
|
R. 54, nr 5
254-257
EN
The paper compares the accuracy of a computerized instrument using the CYFORM software with that of a traditional instrument for measuring roundness profiles equipped with an analogue dial gauge. The results for the two instruments were compared with those obtained by a standard Taylor-Hobson TALYROND 73. The work discusses the procedures of the statistical analysis of the experimental method error and the accuracy of the instruments tested.
PL
W niniejszym artykule przedstawiono porównanie wyników uzyskanych za pomocą przyrządu do pomiaru zarysów okraglości w urządzeniach technologicznych w wersji tradycyjnej tj. wyposażonej w analogowy czujnik zegarowy, ze skomputeryzowanym przyrządem pomiarowym działającym przy użciu oprogramowania CYFORM. Porównania dokonano względem urządzenia wzorcowego TALYROND 73 firmy Taylor-Hobson. Przedstawiono procedury testowania statystycznego eksperymentalnego błędu metody. Ustalono i podano dokładność testowanych urządzeń oraz na ich podstawie sformulowano wnioski.
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