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1
Content available remote Application of microwave radiation in innovative process of neutralising asbestos-containing wastes
Granat K., Nowak D., Pigiel M., Florczak W., Opyd B.
Archives of Civil and Mechanical Engineering
|
2015
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Vol. 15, no. 1
188--194
EN
Presented are results of a research on a possibility to use innovative microwave heating for thermal neutralisation of asbestos-containing wastes. In comparison to traditional heating, the innovative process is characterised by up to a hundred times reduced energy consumption and two hundred times shorter processing time. Parameters of effective disposal, i.e. microwave radiation power and heating time, as well as kind and quantity of the wetting agent necessary in the microwave heating process that intensifies the process and ensures uniform heat distribution in the heated charges, were determined for five most commonly used products containing various fractions of asbestos fibres. It was demonstrated that the presented innovative and eco-minded technology of disposing asbestos-containing materials is a quick, cheap, economical and effective solution guaranteeing complete degradation of the hazardous fibres.
2
Content available Badania gazów powstałych w procesie mikrofalowej utylizacji mas formierskich. Część 1
Samociuk B., Granat K., Nowak D., Stachowicz M., Pigiel M.
Archives of Foundry Engineering
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2013
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Vol. 13, iss. 1 spec.
159--162
PL
W artykule przedstawiono wyniki badań gazów, powstałych podczas utylizacji wybranych mas formierskich w reaktorze mikrofalowym, z punktu widzenia ich szkodliwości dla otoczenia. Metodą chromatografii gazowej analizowano gazy z pięciu mas formierskich (cztery ze spoiwem organicznym i jedną z nieorganicznym). Do utylizacji mas formierskich wykorzystano półprzemysłowy reaktor mikrofalowy. Analizując wyniki badań stwierdzono, że nastąpiło przekroczenie wartości największych dopuszczalnych stężeń gazów wytlewnych, określonych w Dyrektywie Unii Europejskiej wskaźnikiem szkodliwości dla otoczenia, jedynie w przypadku masy z żywicą fenolową Fenotec P439.
EN
In this work the influence of gases emitted from utilization of molding sand on the enviroment was studied. Five different molding sands were examined by gas chromatographic method. The analysis showed that the utilization of molding sands in the microwaves reactor found larger than allowable concentrations of gases only in the molding sand with phenolic resin Fenotec P439.
3
Content available Pochłanianie mikrofal przez zużyte masy formierskie i rdzeniowe
Nowak D., Stachowicz M., Granat K., Pigiel M.
Archives of Foundry Engineering
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2012
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Vol. 12, iss. 1s
149--152
PL
W pracy zaprezentowano wyniki badań pomiaru współczynnika fali stojącej dla oceny skuteczności pochłaniania mikrofal przez zużyte masy formierskie i rdzeniowe wytypowane do przeprowadzenia z ich udziałem procesu mikrofalowej utylizacji. Badania pochłaniania mikrofal zostały przeprowadzone z wykorzystaniem prototypowego stanowiska mikrofalowej linii szczelinowej. Badaniom poddano pięć zużytych mas formierskich i rdzeniowych. Wykazano, że uzyskane wyniki pochłaniania mikrofal mas formierskich i rdzeniowych daje podstawy do przeprowadzenia z ich udziałem procesu mikrofalowej utylizacji.
EN
The paper presents measurement results of standing wave ratio to be used as an efficiency indicator of microwave absorption by used moulding and core sands chosen for the microwave utilization process. The absorption measurements were made using a prototype stand of microwave slot line. Examined were five used moulding and core sands. It was demonstrated that the microwave absorption measurements can make grounds for actual microwave utilization of moulding and core sands.
4
Content available Microwave absorption by used moulding and core sands
Nowak D., Stachowicz M., Granat K., Pigiel M.
Archives of Foundry Engineering
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2012
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Vol. 12, iss. 3
87-90
EN
The paper presents measurement results of standing wave ratio to be used as an efficiency indicator of microwave absorption by used moulding and core sands chosen for the microwave utilization process. The absorption measurements were made using a prototype stand of microwave slot line. Examined were five used moulding and core sands. It was demonstrated that the microwave absorption measurements can make grounds for actual microwave utilization of moulding and core sands.
5
Content available Possibility of utilizing thermosetting moulding sands by microwave heating
Granat K., Nowak D., Stachowicz M., Pigiel M.
Archives of Foundry Engineering
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2011
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Vol. 11, iss. 3 spec.
71--74
EN
The paper presents a semi-industrial reactor designed for utilisation of waste moulds and cores made of thermosetting moulding sands by microwave incinerating. It was found that a possibility exists of effective incinerating residues of this kind waste cores or moulds left after casting. The research evidences that the apparatus permits effective control of the applied microwave heating process. Preliminary tests of microwave heating indicated that incinerating waste moulds and cores made of industrially used moulding sands based on phenolic-formaldehyde resins is an effective method of their utilization. Application of microwave heating for incinerating waste moulds and cores containing synthetic resins as binders guarantees significant and measurable economical benefits resulting from reduced process time.
6
Content available remote Possibilities of utilizing used moulding and core sands by microwave treatment
Granat K., Nowak D., Stachowicz M., Pigiel M.
Archives of Foundry Engineering
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2011
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Vol. 11, iss. 1
35-38
EN
The paper presents a semi-industrial reactor designed for microwave utilization of waste moulds and cores made of moulding sands prepared in furane resin technology. It was found that a possibility exists of effective incinerating this way prepared residues of cores separated from moulding sands or waste moulds left after casting. The preliminary tests evidenced that microwave heating is an effective way of disposing waste moulding sands and the applied apparatus permits effective control of the microwave heating process. The special structure permitting rotations of charge material and proper selection of the generators working cycles guarantee significant speeding-up the process and its full stabilisation. Application of microwave heating for utilization of waste moulds and cores containing synthetic resins as binders ensures significant and measurable economical benefits resulting from shorter process time.
7
Content available remote The possibilities of the microwave utilization of wastes on the example of materials containing the asbestos
Pigiel M., Granat K., Nowak D., Florczak W., Stachowicz M.
Archives of Foundry Engineering
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2010
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Vol. 10, iss. 2 spec.
119--122
EN
The presented paper introduce some of the results of the investigations in the utilization of the materials containing asbestos in the existing in Wroclaw University of Technology Institute’s of Technology of Machines and the Automation Foundry and Automation Group the microwave reactor. In the reactor’s heating chamber there is possible to recycle from 3 up to 5 kg of the batch at once. The temperature with which is possible to receive in it is approx. 1400oC. The time of it’s achievement (in dependence from utilized material) can take out from 25 up to 40 minutes.
PL
W niniejszym opracowaniu przedstawiono niektóre z wyników badań utylizacji związków azbestu w istniejącym w Zakładzie Odlewnictwa i Automatyzacji Instytutu Technologii Maszyn i Automatyzacji Politechniki Wrocławskiej reaktorze mikrofalowym. W komorze grzewczej reaktora można jednorazowo utylizować od 3 do 5 kg wsadu. Temperaturę jaką można w niej otrzymać to ok. 1400oC. Czas jej osiągnięcia (w zależności od utylizowanej materiału) może wynosić od 25 do 40 minut.
8
Content available remote Microwave reactor for utilizing waste materials
Pigiel M., Granat K., Nowak D., Florczak W.
Archives of Foundry Engineering
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2010
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Vol. 10, iss. 1 spec.
251--254
EN
The paper presents a designed and manufactured, semi-industrial microwave reactor for thermal utilization of asbestos-bearing wastes. Presented are also semi-industrial tests of utilizing such wastes. It was found that microwave heating can be applied for utilizing asbestos with use of suitable wetting agents. The wetting agents should ensure continuous heating process above 600 °C, as well as uniform heat distribution in the whole volume of the utilized material. Analysis of the neutralization process indicates a possibility of presenting specific, efficient and effective process parameters of utilizing some asbestos-bearing industrial wastes.
9
Content available remote Microstructures and selected properties of cast irons used for bridge structures at late XVIII and in XIX century
Granat K., Pękalski G., Pigiel M., Rabiega J.
Archives of Foundry Engineering
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2010
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Vol. 10, iss. 1 spec.
107--112
EN
During recent years, in the area of Germany and Poland numerous repair and renovating works are being carried out of old (of XVIII and XIX centuries) structures of bridges and overbridges. In Germany, such works are preceded by generous research programs resulting in well-grounded diagnoses on f their wear conditions and properties of that time used construction materials. In Poland, such research works result more from own interest of the individual authors of published papers and elaborations. In Wroclaw (Breslau), in use are In this paper, the research subject were cast iron fragments of structure of the Old Mieszczanski Bridge (Wilhelmsbrücke) of 1876 and pillars of the railway overbridge built in 1899. The research was aimed at determining chemical composition of the used materials, their structure properties, as well as selected mechanical properties and referring the results to structures and properties of modern cast irons. It was found using light microscopy and SEM methods that they are grey cast irons with flake graphite, with ferritic and pearlitic matrices. Moreover, they include significant areas of phosphide eutectics and precipitates of titanium-rich phases. These observations are confirmed by results of gravimetric and spectral chemical analyses which indicate maximum phosphorus content of 1.18 % and maximum titanium content of 0.1 % in the examined cast irons. Together with evaluated mechanical properties (based on hardness measurements and previous results), chemical compositions and structures permit classifying the examined materials as cast irons equivalent to grades EN-GJL-100 and EN-GJL-150 acc. to the today's standards.
10
Content available remote Evaluation of electromagnetic absorbing capacity of materials in foundry industry
Nowak D., Stachowicz M., Pigiel M.
Archives of Foundry Engineering
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2010
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Vol. 10, iss. 1 spec.
237--242
EN
In the paper, a research on determining the standing wave ratio as a measure of electromagnetic absorbing capacity of moulding materials is presented. Preliminary tests performed using a microwave strip line showed that high-silica, chromite and magnesite moulding sands are characterised by low absorbing capacity of microwaves. It was demonstrated that microwave absorbing capacity is significantly affected by chemical compounds included in the examined substrates. It was found that use of a microwave strip line permits precise determining characteristic microwave absorbing capacities of various moulding materials and thus their suitability for microwave drying/hardening of moulds and cores or for other foundry processes. Such a microwave drier can be applied for identifying mass components and for determining e.g. base granularity by means of precisely determined reflection ratios |Γ| and positions of minimum signal values.
11
Content available remote Determination of application possibilities of microwave heating in the curing process of water glass molding sands with fluid esters. Part 2
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
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2009
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Vol. 9, iss. 1
51-56
EN
This article, constituting continuation of the subject discussed in the first part, presents results of the experimental trial of water glass molding sands' curing method modification with application of fluid esters and innovative microwave heating. The research objective was to determine possibilities of microwave application for curing of water glass molding sands prepared with addition of hardening agents sold under the trade name of Mach. After initial chemical curing molding sands, prepared with addition of the above mentioned hardeners, have been heated with microwaves in order to determine their influence on changes of basic technological and strength parameters of the sands, and indirectly on the quality of quartz grains binding. Studies aimed at determination of water content changes in the sands have also been undertaken. As our studies demonstrated, microwave heating allows for quick reduction of water content, thus resulting in improvement of strength parameters such as bending and tensile strength. Application of the combined methods of ester curing and innovative microwave heating facilitates production of high quality foundry moulds and cores, while simultaneously improving mould and core preparation procedures at the foundries and as a result reduces their time to an indispensable minimum.
12
Content available remote Determination of application possibilities of microwave heating in the curing process of water glass molding sands with fluid esters. Part 1
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
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2009
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Vol. 9, iss. 1
45-50
EN
This article presents results of the experimental trial of combination of the chemical method of water glass molding sands' curing, used in foundry industry, with an innovative microwave heating. The research objective was to indicate at new areas of microwave energy application. The sands prepared, according to recommendations for curing technology, with the use of ethylene glycol diacetate, have been subject to microwave influence. The attempt at determination of microwave influence on qualitative changes of the binding bridges created during the curing process concerned such parameters as: bending and tensile strength, permeability as well as wear resistance. Moreover, we also determined the influence of microwave curing on the phenomena accompanying the process as well as bond stability (storage time of the prepared molding and core sands). It has been found, basing on the result analysis, that the innovative microwave heating might constitute a very good supplementation of the ester curing method. The advantages of the combined chemical and microwave gelation process include, among others, improvement of the described resistance and technological parameters as well as significant decrease of preparation time of foundry moulds and cores. The subject discussed in this article will be continued in its second part.
13
Content available remote The influence of water glass on the properties of microwave cured molding sands
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 1 spec.
123--126
EN
This work presents results of research on the influence of microwave heating time on the process of hardening of microwave cured molding sands. Essential influence of this drying process on basic properties such as: compression, bending and tensile strength as well as permeability and wear resistance, while supplementing and reinforcing influence of water glass addition on these parameters, known from practice as well as literature, has been found. A beneficial influence of hardening (drying) process has been observed in case of all available on the market kinds of this binding agent (including the most frequently used in foundry 145 and 149 kinds). It has been proved, that microwave heating guarantees obtaining very good, in comparison to traditional carbon dioxide hardening process, strength and resistance properties as well as technological characteristics of molding sand with only 1.0 up to 1.5% content of water glass. Microwave curing of water glass moldings sands guarantees, apart from a significant process time reduction, a full stabilization of their properties as well as considerable lower energy consumption and allows for amount reduction of the used binding agent and, as a result, improvement of knock-out properties of the sands. Microwave heating of water glass molding sands, through suitable process parameter selection, results in the possibility of forecasting and control of their properties.
14
Content available remote The influence of microwave heating and water glass kind on the properties of molding sands
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 1 spec.
119--122
EN
This work presents results of research on the influence of microwave heating time on the process of hardening of water glass molding sands. Essential influence of this drying process on basic properties such as: compression, bending and tensile strength as well as permeability and wear resistance, has been found. It has been proved, that all the investigated sorts of sodium water glass could be used as binding material of molding sands intended for curing with the microwave process heating. It has been found, while analyzing the results of property studies of microwave heated molding sands with 2.5% addition of water glass, that all available on the market kinds of this binding agent (including the most frequently used in foundry 145 and 149 kinds) after microwave heating guarantee very good compression, bending and tensile strength as well as permeability and wear resistance. Moreover, it has been determined that the optimal curing power of molding sands containing various kinds of water glass is 560 W. All values exceeding this result in stabilization of basic properties of molding sands. The use of microwave curing of water glass molding sands results in a significant decrease of hardening a process time, full stabilization of molding sands as well as much lower energy consumption.
15
Content available remote Measurement of standing wave ratio for evaluation of microwave absorption efficiency by molding materials
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 3s
31--34
EN
The presented work includes results of standing wave measurement for evaluation of microwave absorption efficiency by molding materials. Initial research has been conducted using microwave gap line. It has been demonstrated that foundry quartz sands have minimal microwave absorption capability. The following binders used for research: bentonite „Geco” and bentonite „Specjal”, demonstrated the highest absorption of Pabs microwave power output of over 60% Pin. It has also been demonstrated that water content, constituting component of synthetic molding sands, significantly influences change of microwave absorption. We have established that application of this kind of measuring device may allow for precise determination of characteristic features, such as microwave absorption factor k, of various foundry materials as well as determination of their suitability in foundry processes, e.g. microwave formation of foundry molds and cores. Microwave gap line may also serve as a device for precise determination of water content as well as other molding sand components and for their identification with the use of characteristic parameters, e.g. reflection factor |Γk|.
16
Content available remote Application of microwaves for incinerating waste shell moulds and cores
Granat K., Pigiel M., Florczak W.
Archives of Foundry Engineering
|
2008
|
Vol. 8, iss. 3s
167--170
EN
In the paper, investigation results of microwave heating application for incinerating waste shell moulds and cores made of moulding sands with thermosetting resins are presented. It was found that waste shell cores or shell moulds left after casting, separated from moulding sand, can be effectively incinerated. It was evidenced that microwave heating allows effective control of this process and its results. Incineration of waste moulds and cores made of commercial grades of resin-coated moulding sand using microwave heating was found to be an effective way of their utilisation. It was determined that the optimum burning time of these wastes (except those insufficiently disintegrated and not mixed with an activating agent) is maximum 240 s at the used magnetron power of 650 W. It was noticed that proper disintegration of the wastes and use of suitable additives to intensify the microwave heating process guarantee significant reduction of the process time and its full stabilisation. Application of microwave heating for incinerating waste shell moulds and cores ensure substantial and measurable economic profits due to shorter process time and lower energy consumption.
17
Content available remote Application of microwave energy for curing of molding sands containing oil binders
Stachowicz M., Granat K., Pigiel M.
Archives of Foundry Engineering
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2008
|
Vol. 8, iss. 2
129-132
EN
This works presents the results of studies concerning possibility of application of microwave heating in the curing process of molding sands containing oil binders. Molding sands prepared with three kinds of binders, that is oils C, DL and Retanol, have been subject to experiments. The sands have been dried with two methods: in a microwave chamber of 750W power and, for comparison, with classical method at the temperature of 200°C for 120 minutes. Tensile and bending strength of the samples have been determined after cooling down. It has been found that microwave drying in the low-power device used for experiments is effective only in case of molding sand prepared with addition of DL binder. The temperature of heated, even up to 32 minutes in a microwave chamber, blocks prepared from the remaining two masses, was insufficient to initiate binding process. The undertaken attempts of binder modification and introduction of additives intensifying microwave heating process allowed for achievement of satisfactory results. It has been found that power of the heating device is the main factor determining efficiency of microwave curing of molding sands containing oil binders. An additional experiment has been conducted on a laboratory workstation allowing for microwave heating of small mass samples with a high output power of magnetron concentrated in a small substrate volume. It has been observed that microwave drying process of molding sands was of dynamic character over a short period of time, not exceeding 120 seconds, thus assuring efficient curing of the sands containing the used oil binders. Therefore, application of devices of properly high microwave output power allows for efficient drying of oil molding sands, while simultaneously assuring the possibility to reduce time and energy consumption necessary for production of foundry cores of proper functional characteristics.
18
Content available remote The influence of microwave curing time and water glass kind on the properties of molding sands
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
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2007
|
Vol. 7, iss. 4
79-82
EN
This work presents results of research on the influence of microwave heating time on the process of hardening of water glass molding sands. Essential influence of this drying process on basic properties such as: compression, bending and tensile strength as well as permeability and wear resistance, has been found. It has been proved, that all the investigated sorts of sodium water glass could be used as binding material of molding sands intended for curing with the microwave process heating. It has been found, while analyzing the results of property studies of microwave heated molding sands with 2.5% addition of water glass, that all available on the market kinds of this binding agent (including the most frequently used in foundry 145 and 149 kinds) after microwave heating guarantee very good compression, bending and tensile strength as well as permeability and wear resistance. Moreover, it has been determined that the optimal curing time of molding sands containing various kinds of water glass is 240 seconds. After this time, all basic properties of molding sands are stable. The use of microwave curing of water glass molding sands results in a significant decrease of hardening process time, full stabilization of molding sands as well as much lower energy consumption.
19
Content available remote Microwaves energy in curing process of water glass molding sands
Granat K., Nowak D., Pigiel M., Stachowicz M., Wikiera R.
Archives of Foundry Engineering
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2007
|
Vol. 7, iss. 1
183-188
EN
This work presents the results of investigation of microwave heating on hardening process of water glass molding sands. Essential influence of this heating process on basic properties such as: compression, bending and tensile strength as well as permeability and abrasion resistance has been found. It has been proved, that all investigated sorts of sodium water glass with a module between 2.0 and 3.3 can be used as a binder of molding sands in microwave curing process. It has been found during analysis of research results of sands with 2.5 % water glass addition that they are practically the same as in case of identical molding sands dried for 120 minutes at the temperature of 110°C, used for comparative purposes. Application of microwave curing of molding sands with water glass, however, guarantees reduction of hardening time (from 120 to 4 minutes) as well as significant reduction of energy consumption. Attempts of two stage hardening of the investigated water glass molding sands have also been carried out, that is after an initial hardening during a classical CO_2 process (identical sands have also been tested for comparison after CO_2 blowing process) and additional microwave heating. It has been found that application of this kind of treatment for curing sands with 2.5 % sodium water glass content and module from 2.0 up to 3.3 results in the improvement of properties in comparison to classical CO_2 process.
20
Content available remote Application of graftech method for pro-gramming of discrete technological process
Pigiel M., Więcławek R., Wikiera R.
Archives of Foundry Engineering
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2007
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Vol. 7, iss. 1
9-12
EN
This article contains description of a new programming method of PLC controllers, presently a fundamental tool in discrete process auto-mation. A PLC user, applying standard languages for programming of sequence processes, is forced to rely on intuitive methods as well as his own experience. For this reason, the authors attempted to work out a method, which would allow for simple execution of the program-ming process with no limits regarding number of steps and input and output signals. The result of these studies is a method named Graftech by its authors. The method consists in determination of a functional program in LD language, basing on process algorithm written with SFC network. The rules concerning determination of the functional program are also described. Application of Graftech method is illustrated with an example of automatic ejector of casting molds.
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