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1

Application of the Triboelectric Method for the Ongoing Assessment of the Quality of Reclaim in Mechanical Reclaimers

Dańko R., Pietrzak A., Gruszka D.

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 2

63--70

EN

The method of the ongoing assessment of the reclaim quality originating from the mechanical reclamation is described in this paper. In the process, the triboelectric system of measuring amounts of dust in the dedusting part of a reclamation device was applied. Based on the online measurements of the amounts of dust generated in the spent sand-reclamation process and the post-process determinations of the ignition losses and granular structures of the removed dust, the proper work parameters of the experimental reclaimer were selected. The allowable value of the ignition losses as well as the main fraction of the reclaimed matrix being similar to fresh sand was assumed as the main criteria of the positive assessment of the process. Within the presented investigations, a periodically operating device for rotor-mechanical reclamation was developed. The possibility of changing the intensity and time of the reclamation treatment as well as the triboelectric system of the dust-amount measuring were applied in this device. Tests were performed for the spent moulding sand with phenol-resol resin Carbophen 5692 hardened by CO2. This sand represents the moulding sand group with a less harmful influence on the surroundings for which the recovery of the quartz matrix utilising the reclamation requires stricter control of the parameters of the reclamation process and reclaim quality.

2

Primary Used Sand Reclamation Process Efficiency

Skrzyński M., Dańko R.

Archives of Foundry Engineering

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2019

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iss. 1

29--34

EN

The results of the efficiency of the primary reclamation process as well as the influence of the used sand temperature and other process parameters on it are presented in this paper. A separate stand realized on a reduced scale was built, which is an analogous process of the primary reclamation treatment of spent foundry sands. The used sands were introduced to the crushing process in an agglomerated form in the way typically used in industrial devices. The primary reclamation process was realized on a set of four horizontal sieves with decreasing mesh clearances while maintaining their geometrical dimensions applied in the Regmas industrial device. The model system consists of a vibratory drive mounted on the table, allowing us to control the supply frequency of the vibratory motors within a range of 40-60 Hz as well as the computer system for measuring the vibration parameters and drive power. The used sand on the quartz matrix with the KALTHARZ U404 resin and 100T3 hardener was used in our investigations. The used sand was prepared under the following conditions: cubic-shaped elements made of the applied furan sand was compacted by vibrations then hardened and subjected to heating under controlled conditions (as a “simulation” of the overheating process taking place in the mold after pouring). Time functions of the crushing and sieving process in dependence of the overheating degree of the reference sand samples (100°, 200°, and 300°C) were investigated at various table vibration frequencies and feed loads of the sieve set. The relative index of the crushing ability was determined.

3

Effect of Mechanical Reclamation Cycle on Strength Parameters of Loose Self-Hardening Sands Based on Furfuryl Resin

Kamińska J., Basińska E., Angrecki M., Palma A.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1843--1846

EN

The results of mechanical reclamation of waste moulding sands with furfuryl resin and activators of new generation are presented. The aim of the research described in this study was to determine what effect the addition of reclaim obtained in the process of dry mechanical reclamation could have on the properties of furan sands. The sand supplied by one of the domestic foundries was after the initial reclamation subjected to a two-step proper reclamation process. The following tests were carried out on the obtained reclaim: pH, S and N content, loss on ignition and comprehensive sieve analysis. The obtained reclaim was next used as a component of moulding sands with furfuryl resin, wherein it formed 50% and 80% of the base moulding material, respectively. The strength properties of the ready sand mixtures (bending strength Rgu and tensile strength Rm u ) were determined after the hardening time of 0.5, 1, 2, 4 and 24 hours.

4

Influence of the reclamation method of spent moulding sands on the possibility of creating favourable conditions for gases flow in a mould

Łucarz M., Drożyński D.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 1

359--364

EN

The results of investigations concerning the influence of the applied sand matrix (fresh sand, reclaim) on the properties of moulding sands used for production of large dimensional castings (ingot moulds, ladles), are presented in the hereby paper. The performed investigations were aimed at determining the influence of various reclamation methods of spent moulding sands on the quality of the obtained reclaimed material. Moulding sands were prepared on the fresh quartz matrix as well as on sand matrices obtained after various reclamation methods. The selected moulding sand parameters were tested (strength, permeability, grindability, ignition losses, pH reactions). It can be stated, on the basis of the performed investigations, that the kind of the applied moulding sand matrix is of an essential meaning from the point of view of creating conditions minimising formation of large amounts of gases and their directional migration in a casting mould.

5

Conditions of Thermal Reclamation Process Realization on a Sample of Spent Moulding Sand from an Aluminum Alloy Foundry Plant

Łucarz M., Dereń M.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 2

197--201

EN

The results of investigations of thermal reclamation of spent moulding sands originating from an aluminum alloy foundry plant are presented in this paper. Spent sands were crushed by using two methods. Mechanical fragmentation of spent sand chunks was realized in the vibratory reclaimer REGMAS. The crushing process in the mechanical device was performed either with or without additional crushing-grinding elements. The reclaimed material obtained in this way was subjected to thermal reclamations at two different temperatures. It was found that a significant binder gathering on grain surfaces favors its spontaneous burning, even in the case when a temperature lower than required for the efficient thermal reclamation of furan binders is applied in the thermal reclaimer. The burning process, initiated by gas burners in the reclaimer chamber, generates favorable conditions for self-burning (at a determined amount of organic binders on grain surfaces). This process is spontaneously sustained and decreases the demand for gas. However, due to the significant amount of binder, this process is longer than in the case of reclaiming moulding sand prepared with fresh components.

6

Investigation of the Results of Combined Reclamation on the Particular Stages of Grain Matrix Recovery

Łucarz M., Dańko R., Dereń M., Skrzyński M.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 4

2151--2158

EN

In this article, there were presented the results of research on combined mechanical and thermal regeneration of waste moulding sand with furfuryl resin originated from one of national foundries manufacturing aluminium alloys castings. Attempts of mechanical reclamation were led on the REGMAS reclaimer enabling to realize preliminary and primary reclamation with use of two modes of mechanical interactions on waste moulding sand. In the first attempt the reclaimer worked without any additional regenerating elements, and as the second solution, the reclaimer operated with additional crushing and abrasive elements to increase the result of primary reclamation. Thermal reclamation was led in the prototypic thermal reclaimer, enabling to fully control the process of grain matrix recovery. As a result of completed investigations the small efficiency of mechanical reclamation was determined. However, use of combined regeneration allowed for obtaining grain matrix of high purity. Thermal regeneration was conducted in prototypic thermal reclaimer. Evaluation of reclaim (reclaimed material) quality was carried out in the way of iginition losses and grain-size analysis, surface morphology and also by executing of strength testing of moulding sand prepared on obtained grain matrix for the particular reclamation operations.

7

State of Spent Molding Sands in the Mold Large-Size Cast

Łucarz M.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 4

69--74

EN

The results of investigations of spent moulding sands taken from the mould at various distances from the surface of the produced casting, are presented in the paper. The casting mould was made with an application of the cooling system of the metal core in order to increase the cooling rate of the ladle casting. As temperature measurements in the mould indicated the heat flow from the metal did not create conditions for the complete burning of a moulding sand. The analysis was performed to find out changes of spent moulding sands caused by degradation and destruction processes of organic binders. Conditions occurring in the casting mould were discussed on the bases of testing: ignition losses, dusts contents, pH reactions and the surface morphology of the moulding sand samples. Factors limiting the effective mould degassing were pointed out. Operations, possible for realisation, which can limit the reasons of a periodical occurrence of increased amounts of casting defects due to changing gas evolution rates being the result of the technological process, were also indicated.

8

Badania laboratoryjne odlewniczych mas formierskich

Major-Gabryś K., Dobosz S. M., Grabarczyk A.

Laboratorium - Przegląd Ogólnopolski

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2015

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nr 11-12

62--64

PL

W artykule zostały przedstawione stosowane laboratoryjne metody pomiaru wybijalności mas. Zaproponowano nową metodę oceny tej właściwości, której zalety wykazano, testując zmodyfikowane przez autorów odlewnicze masy formierskie z uwodnionym krzemianem sodu. Masy te cechuje mała szkodliwość dla środowiska, niestety ich wady to zła wybijalność oraz mała zdolność do regeneracji mechanicznej.

EN

The article presents commonly used methods of measuring moulding sands knock-out properties. A new method of estimation of this parameter is presented, its’ advantages are proved by tests of modified foundry moulding sands with hydrated sodium silicate. They are environmentally friendly, but unfortunatelythey have bad knock-out properties and low mechanical reclamation ability.

9

Investigations of Physicochemical Properties and Thermal Utilisation of Dusts Generated in the Mechanical Reclamation Process of Spent Moulding Sands

Dańko R., Holtzer M., Dańko J.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 1

313--318

EN

The after reclamation dusts originated from various foundry plants, applying moulding sands with organic binding agents, mostly resins, are characterised by different properties in dependence of the used binders, reclamation systems, spent sands overheating degree and the efficiency of the system dedusting the reclaimed material operating in individual foundry plants. In the article the results of investigations of physicochemical properties and thermal utilisation possibility referring to six kinds of after reclamation dusts generated in the mechanical reclamation process of spent moulding sands with furfuryl resins and six other kinds of after reclamation dusts obtained from reclamation process of spent moulding sands with alkaline resins have been presented. All tested dusts originated from various Polish foundry plants of cast iron and cast steel applying the mechanical reclamation process of moulding sands with resins, obtained from different producers.

PL

W artykule przedstawiono charakterystykę pyłów powstających w procesie regeneracji mechanicznej mas zużytych ze spoiwami organicznymi, głównie żywicami. W badaniach uwzględniono rodzaj użytego spoiwa, system regeneracji, stopień przepalenia masy formierskiej oraz skuteczność systemu odpylania systemu regeneracji zainstalowanego w instalacjach przemysłowych. Badaniu poddano właściwości fizykochemiczne oraz możliwości utylizacji termicznej sześciu rodzajów pyłów poregene-racyjnych powstających w procesie regeneracji mechanicznej mas zużytych z żywicą furfurylową oraz sześciu rodzajów pyłów powstających w procesie regeneracji mechanicznej mas zużytych z żywicą alkaliczną. Wszystkie pyły poddane badaniom pochodziły z krajowych odlewni żeliwa i staliwa stosujących technologię mas samoutwardzalnych z żywicami pochodzącymi od różnych producentów, w których stosowana jest mechaniczna regeneracja mas zużytych.

10

Utilisation of Products of the Thermal Reclamation of Post Reclamation Dusts in the Production Technology of Ceramic Building Materials

Holtzer M., Dańko R., Dańko J., Pytel Z.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 4

33--36

EN

The problem related to the management of post reclamation dusts generated in the reclamation process of waste moulding sands with organic binders is presented in the hereby paper. Waste materials generated in this process are products hazardous for the environment and should be utilised. The prototype stand for the utilisation of this dangerous material in its co-burning with coal was developed and patented in AGH in Krakow. The stand was installed in one of the domestic casting houses. As the utilisation result the transformed waste product is obtained and its management in the production of ceramic materials constitutes the subject of the presented publication.

11

Used Furan Sand Reclamation in REGMAS Vibratory Unit

Dańko J., Dańko R., Skrzyński M.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 3

25--28

EN

The paper, especially dealt with problems of reclamation of used furan sand, carried out in new, vibratory sand reclamation unit REGMAS developed by researches from AGH-University of Science and Technology, Faculty of Foundry Engineering in Cracow (Poland). Functional characteristics of reclamation unit as well as the results of reclamation of used sand with furfuryl resin are discussed in the paper. The quality of reclaim was tested by means of the LOI and pH value, dust content in the reclaim and at least by the the quality of the castings produced in moulds prepared with the use of reclaimed matrix.

12

Wykorzystanie regeneratu z technologii cold-box do wykonywania mas rdzeniowych

Łucarz M.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 3 spec.

107--112

PL

W publikacji przedstawiono wyniki badań wpływu różnych sposobów regeneracji zużytych mas rdzeniowych na możliwość wykorzystania otrzymanego regeneratu do sporządzania rdzeni w technologii cold-box. Regenerację wykonano w dwóch urządzeniach: regeneratorze mechanicznym REGMAS i doświadczalnym regeneratorze termicznym. W wyniku zrealizowanych badań określono obszar działań, które można podjąć w celu wykorzystania regeneratu do produkcji rdzeni w technologii cold-box. Na bazie pozyskanego regeneratu po obróbce mechanicznej i dodatkowej obróbce termicznej wykonywano rdzenie do badania wytrzymałości na zginanie. Oceniano także wpływ dodatku świeżego piasku do regeneratu, w różnych proporcjach, na jakość otrzymywanych rdzeni pod względem wytrzymałości. Stwierdzono, na podstawie strat prażenia oraz odczynu pH, dużo większą skuteczność regeneracji kombinowanej (mechaniczno-termicznej) w stosunku do zastosowanej tylko regeneracji mechanicznej na oczyszczenie osnowy ziarnowej ze spoiwa. Wykazano także korzystny wpływ dodatku świeżego piasku do regeneratu na parametry wytrzymałościowe masy rdzeniowej wykonanej w technologii cold-box.

EN

The investigation results of influences of various reclamation methods of spent moulding sands on the possibility of applying the obtained reclaimed material for preparation of cores in the cold-box technology, are presented in the hereby paper. Reclamations were carried out in two devices: the mechanical reclaimer REGMAS and experimental thermal reclaimer. As the result of the performed investigations the range of operations, which can be undertaken in order to utilise the reclaimed material for cores production in the cold-box technology, was determined. On the bases of the obtained reclaim, after its mechanical treatment and an additional heat treatment, cores for bending strength tests were made. The influence of fresh sands additions to the reclaim - in various proportions - on the strength quality of the obtained cores, was also estimated. It was found, on the bases of ignition losses and pH values, that the effectiveness of the combined reclamation methods (mechanical- thermal) was much higher than the mechanical cleaning of matrix grains from binding materials. A beneficial influence of fresh sand additions on the strength parameters of the core sands made in the cold-box technology was also shown.

13

Reclamation of spend moulding sands with the Carbophen 8178 resin

Kamińska J., Kmita A., Kolczyk J., Żymankowska-Kumon S.

Metallurgy and Foundry Engineering

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2012

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Vol. 38, no. 2

163--170

EN

The aim of investigations was to collect the experimental data allowing the quality assessment of the reclaimed material obtained by means of the mechanical reclamation from spent sands with the Carbophen 8178 resin. The investigation program was as follows: - making the moulding sand with the Carbophen 8178 resin and its preparation for the primary reclamation; - carrying out the secondary reclamation of the spent sand in the experimental mechanical reclaimer, at several variable parameters (inclination, reclamation time, rotor rotational speed); - necessary instrumental tests of the reclaimed spent sand and the analysis of the obtained reclaimed materials Investigations were carried our for three positions of the apparatus: a = 0°, 3°, 6°. The reclamation was performed for each position at three rotational speeds of impact-abrasive elements. The reclamation process effects were checked after 5, 10, 15 and 20 minutes. The reclamation results for the average rotational speed of the rotor, being 700 rpm, are presented in the paper

PL

Celem badań było zgromadzenie danych doświadczalnych pozwalających na oceną jakości re-generatu uzyskanego z masy zużytej z żywicą Carbophen 8178 sposobem regeneracji mechanicznej. Program badań własnych obejmował: - wykonanie masy z żywicą Carbophen 8178 i jej przygotowanie do regeneracji (regeneracja wstępna); - regenerację właściwą masy zużytej w doświadczalnym regeneratorze mechanicznym, przy szeregu zmiennych parametrów (nachylenie, czas regeneracji, prędkość obrotowa wirnika); - niezbędne badania instrumentalne regenerowanej masy zużytej oraz analiza uzyskanych regeneratów, Badania były przeprowadzone przy trzech położeniach aparatu: a = 0°, 3°, 6°. W każdym z zadanych położeń została przeprowadzona regeneracja masy przy trzech prędkościach obrotowych elementów udarowo-ściernych. Efekty procesu regeneracji badano po 5, 10, 15 i 20 minutach. W artykule zostały przedstawione wyniki regeneracji przy średniej prędkości obrotowej wirnika wynoszącej 700 obr/min.

14

Wpływ dodatku regeneratu na właściwości mas z żywicą furanową stosowanych na formy do odlewów ze staliwa manganowego

Holtzer M., Bobrowski A., Drożyński D., Isendorf B., Mazur M.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 1s

57--62

PL

W artykule omówiono wpływ dodatku regeneratu uzyskiwanego w procesie regeneracji mechanicznej do masy z żywicą furfurylową na osnowie piasku kwarcowego. Określono wpływ udziału regeneratu na takie parametry masy jak: wytrzymałość na rozciąganie, ścieralność, przepuszczalność i żywotność masy. Badania prowadzono przy udziale regeneratu w osnowie w ilości od 20 do 100%. Uzyskane wyniki wykazały, że optymalne właściwości, uzyskuje masa o składzie 60% regeneratu, 1 cz. mas. żywicy i 0,5 cz. mas. utwardzacza.

EN

The influence of an addition of the reclaim, obtained in the mechanical reclamation process, to the moulding sand prepared on the basis of the high-silica sand with furfuryl resin, was discussed in the paper. The influence of the reclaim fraction on such moulding sand parameters as: tensile strength, wear resistance, permeability and bench life, was determined. Tests were performed at the reclaim fraction in the matrix being from 20 to 100%. The obtained results indicated that the optimal properties were exhibited by the moulding sand containing 60% of the reclaim, 40% new sand and 1 part by weigh of a resin and 0.5 part by weight of a hardener.

15

Praca destrukcji wiązań międzyziarnowych w procesie regeneracji mechanicznej zużytych mas formierskich

Dańko R.

Archiwum Technologii Maszyn i Automatyzacji

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2009

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Vol. 29, nr 3

23-32

PL

W artykule przedstawiono główne założenia teoretyczne i rozwinięcie energetycznego modelu procesu mechanicznej regeneracji suchej zużytych mas formierskich. Podstawą do opracowania teoretycznego modelu oddziaływań krusząco-ściernych w procesie regeneracji mechanicznej zużytych mas formierskich jest deterministyczna hipoteza Rittingera kruszenia materiałów mineralnych o właściwościach zbliżonych do kwarcowej osnowy piaskowej. Wykazano, że rutynowe w odlewnictwie badania granulometryczne osnowy, prowadzone w trakcie analizy sitowej, mogą być wykorzystane do określenia pracy potrzebnej do uwolnienia ziaren osnowy z otoczek materiału wiążącego. Badania powierzchni właściwej osnowy i jej zmiany w trakcie obróbki ścierno-kruszącej masy wnoszą cenne informacje, na podstawie których można opracować kryteria przydatne do oceny, prognozowania i optymalizacji obróbki regeneracyjnej osnowy odzyskanej ze zużytych mas formierskich i rdzeniowych.

EN

The paper, especially dealt with general assumptions of scientific and development research concerning the reclamation of used foundry sands. The backgrounds for elaboration of theoretical model of the crushing-attrition effects appearing in dry mechanical reclamation process was the deterministic Rittinger's hypothesis of crushing mineral materials characterised by properties close to the ones of the quartz sand grains. It was shown, that routine grain size analysis of sand grains performed during the sieve analysis provide valuable information useful for the determination of energy consumption needed for liberation of sand grains from the envelope of used bonding material. Current measuring of grains specific surface and its change during reclamation treatment enables to work out criteria of assessing, forecasting and optimisation of the reclamation treatment of used foundry sands and core sands.

16

Utilization of post-reclamation dusts by combustion and oxidising in a pulsating, fluidised bed

Dańko J., Holtzer M., Dańko R.

Archives of Foundry Engineering

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2008

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Vol. 8, iss. 1 spec.

63--66

EN

Investigations of the utilization process of dusts, originated from the mechanical reclamation of used moulding sands with furfuryl alcohol, were performed. Combustion and oxidation processes of pulverised and separated in cyclones binding agents and other organic components were earried out in the thermal reclaimer where a grain bed underwent pulsating fluidisation either by the atmospheric air or by oxygen enriched air. Factors determining an effective performance of dusts utilization by oxidising in the oxygen enriched air were indicated and the plan for the further research was outlined.

PL

Przeprowadzono badania procesu utylizacji pyłów pochodzących z regeneracji mechanicznej zużytych mas z alkoholem furfurylowym. Procesy spalania i utleniania startych na pył i oddzielonych w cyklonach spoiwa i innych składników organicznych prowadzone były w regeneratorze termicznym zawierającym złoże ziarniste poddane pulsacyjnej fluidyzacji powietrzem atmosferycznym oraz powietrzem o zwiększonej zawartości tlenu. Określono czynniki decydujące o efektywnym prowadzeniu procesu utylizacji pyłów przez wytlewanie w powietrzu wzbogaconym w tlen oraz nakreślono sugestie dalszych badań.

17

Investigation of centrifugal reclaimer's work by means of high-speed digital camera recordings

Łucarz M.

Archives of Foundry Engineering

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2008

|

Vol. 8, iss. 1

92-96

EN

The experimentally verified theoretical model of the mechanical reclamation treatment of used sands in a centrifugal reclamation unit is presented in the paper. The formula for calculation of the single sand grain trajectory on the surface of the disk in a centrifugal reclamation is given. The calculated path of the sand grain moving on the disk surface enabled determination the work of friction force acting on the single sand grain. The calculated trajectory of the particle was compared with the one recorded by the camera at the same disc rotational speed. High-speed camera recordings of the sand grains movement on the disk surface in a wide range of testing conditions are presented in the paper. The influence of different rotational speeds and grain shapes affecting the final sand grain trajectory was experimentally analysed and the discrepancies existing between the theoretical and real trajectory of the particle were explained, which verified the mathematical model of the mechanical reclamation treatment of used sands in a centrifugal reclamation unit.

18

Wpływ wielokrotnej obróbki mechanicznej osnowy kwarcowej na jej zużycie ścierne lub udarowe

Łucarz M.

Archiwum Odlewnictwa

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2006

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R. 6, nr 18/2

393--398

PL

W artykule zaprezentowano wyniki efektów mechanicznego oddziaływania na pojedynczą wyselekcjonowaną frakcję osnowy kwarcowej w mechanicznym regeneratorze odśrodkowym, w którym zastosowano wymiennie pobocznicę obwodową udarową i bezudarową. Analizowano wpływ prędkości pracy urządzenia na osnowę kwarcową. Stwierdzono zróżnicowany charakter procesu niszczenia osnowy w zależności od rozwiązania konstrukcyjnego pobocznicy i zastosowanej prędkości.

EN

In the paper the results of investigations the influence of mechanical reclamation treatment on the wear effect of selected fraction of a silica sand grains was discussed. The wear effect of silica sands gains was a result of multinumbered reclamation cycles realized in a centrifugal reclamation unit, which enabled both impact and impactless treatment of silica grains. In each case the speed of a rotational disc was analyzed as a main factor influenced the effect of silica grains destruction in dependence with above mentioned reclaimer’s parameters.

19

Wpływ intensywności obróbki mechanicznej na niszczenie osnowy kwarcowej

Łucarz M.

Archiwum Odlewnictwa

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2006

|

R. 6, nr 18/2

399--404

PL

W artykule przedstawiono wyniki badania wpływu prędkości obrotowej talerza na wartość graniczną, przy której pojawia się niszczenie ziarn osnowy w odśrodkowym regeneratorze mechanicznym, z jednoczesną zmianą średnicy ziaren osnowy o wyselekcjonowanej wcześniej wielkości. Badania prowadzono dla dwóch rozwiązań konstrukcyjnych pobocznicy obwodowej. Stwierdzono przybliżone wartości prędkości obrotowej regeneratora rozpoczynające proces destrukcji cząstek o różnej masie.

EN

In the paper the results of testing the rotational disc speed influence on the resolution of starting the destruction effect of primary selected fractions of silica sand grains realized in a centrifugal reclamation unit along with changes of diameter of silica grain size have been presented. Investigations were realized considering two different design of peripheral rings adopted in the reclaimer which enabled both impact and impactless way of reclamation treatment exerted on silica grains. As a result of the research the new understanding of the process was obtained regarding the rotational disc speed value initiating the process of destruction of the silica sand grains of different size.

20

Analiza zmian geometrii ziarn osnowy kwarcowej chłodzonej ciekłym azotem i poddanej obróbce w regeneratorze odśrodkowym

Łucarz M., Dańko R.

Archiwum Odlewnictwa

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2006

|

R. 6, nr 18/2

405--410

PL

W artykule przedstawiono wyniki badań uzyskane podczas mechanicznej obróbki ziarn osnowy kwarcowej poddanych wcześniejszemu chłodzeniu ciekłym azotem. Głównymi, badanymi wielkościami podlegającymi analizie, były zmiany geometrii ziarn osnowy kwarcowej podczas obróbki regeneracyjnej ściernej oraz mającej charakter udarowy przy zmiennych prędkościach obrotowych wirnika. Stwierdzono, że osnowa kwarcowa poddana obróbce mechanicznej w zakresie temperatur kriogenicznych podlega znacznie silniejszej destrukcji w porównaniu do analogicznej obróbki prowadzonej w temperaturze otoczenia.

EN

The paper presents the results obtained during mechanical treatment of silica sand originally cooled by the addition of liquid nitrogen. Changes in the geometry of silica sand grains during abrasive and impact reclamation treatment realized at various speed of rotational disc were the main investigated quantities. It was found out that silica sand subjected to the mechanical treatment in extra low temperature is being destructed much faster comparing to the same treatment conducted in ambient temperature.