WO2001054874A1 - Absorbent gypsum form for the production of ceramic bodies from slurry and the production of ceramic bodies from slurry by use of the absorbent gypsum form - Google Patents
Absorbent gypsum form for the production of ceramic bodies from slurry and the production of ceramic bodies from slurry by use of the absorbent gypsum form Download PDFInfo
- Publication number
- WO2001054874A1 WO2001054874A1 PCT/EP2001/000940 EP0100940W WO0154874A1 WO 2001054874 A1 WO2001054874 A1 WO 2001054874A1 EP 0100940 W EP0100940 W EP 0100940W WO 0154874 A1 WO0154874 A1 WO 0154874A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- absorbent
- mold
- carbon fiber
- production
- slip
- Prior art date
Links
- 229910052602 gypsum Inorganic materials 0.000 title claims abstract description 40
- 239000010440 gypsum Substances 0.000 title claims abstract description 40
- 239000000919 ceramic Substances 0.000 title claims abstract description 33
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 25
- 230000002745 absorbent Effects 0.000 title claims abstract description 22
- 239000002250 absorbent Substances 0.000 title claims abstract description 22
- 239000002002 slurry Substances 0.000 title claims abstract description 7
- 238000000034 method Methods 0.000 claims abstract description 21
- 239000011505 plaster Substances 0.000 claims description 34
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 27
- 239000004917 carbon fiber Substances 0.000 claims description 27
- 238000010438 heat treatment Methods 0.000 claims description 27
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 20
- 239000004020 conductor Substances 0.000 claims description 18
- 238000007569 slipcasting Methods 0.000 claims description 15
- 230000015572 biosynthetic process Effects 0.000 claims description 5
- 238000005266 casting Methods 0.000 claims description 5
- 239000004744 fabric Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 claims 1
- 238000007582 slurry-cast process Methods 0.000 abstract 1
- 238000001035 drying Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000012634 fragment Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000006063 cullet Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000005350 fused silica glass Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000011224 oxide ceramic Substances 0.000 description 1
- 229910052574 oxide ceramic Inorganic materials 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
- B28B1/26—Producing shaped prefabricated articles from the material by slip-casting, i.e. by casting a suspension or dispersion of the material in a liquid-absorbent or porous mould, the liquid being allowed to soak into or pass through the walls of the mould; Moulds therefor ; specially for manufacturing articles starting from a ceramic slip; Moulds therefor
- B28B1/261—Moulds therefor
- B28B1/262—Mould materials; Manufacture of moulds or parts thereof
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
- B28B1/26—Producing shaped prefabricated articles from the material by slip-casting, i.e. by casting a suspension or dispersion of the material in a liquid-absorbent or porous mould, the liquid being allowed to soak into or pass through the walls of the mould; Moulds therefor ; specially for manufacturing articles starting from a ceramic slip; Moulds therefor
- B28B1/261—Moulds therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B7/00—Moulds; Cores; Mandrels
- B28B7/40—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material
- B28B7/42—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material for heating or cooling, e.g. steam jackets, by means of treating agents acting directly on the moulding material
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
- H05B3/10—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
- H05B3/12—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material
- H05B3/14—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material the material being non-metallic
- H05B3/145—Carbon only, e.g. carbon black, graphite
Definitions
- Absorbent gypsum mold for the production of ceramic bodies from slip and production of ceramic bodies from slip using the absorbent gypsum mold
- the invention relates to an absorbent gypsum mold for producing ceramic bodies from slip using slip casting processes, a method for producing the absorbent gypsum mold and the use of the absorbent gypsum mold for producing ceramic bodies from slip.
- Ceramic casting compounds also called slips, have an increased water content with liquefying agents, from which more complicated bodies, such as jugs, reliefs, sanitary objects, can be formed with the help of absorbent plaster molds.
- the invention has for its object to make the production of ceramic bodies from slip, in particular also complicated geometries and smaller series more economical.
- an absorbent gypsum mold for producing ceramic bodies from slip using slip casting processes is proposed, which is characterized in that it is heatable by means of a cast-in electrical heating conductor based on a carbon fiber sheet.
- the gypsum mold By producing the gypsum mold with a cast-in heating conductor in the form of a carbon fiber sheet, the gypsum mold can be heated and is already in statu nascendi, i.e. during its own manufacture and, moreover, during later use as a working mold for the slip casting process.
- the invention enables quick and energy-saving drying of the plaster molds during their manufacture.
- Flexible carbon fiber sheets are preferably used as heating conductors, which also have the advantage that carbon fibers have a negative expansion coefficient when heated, so that the gypsum mold cannot be destroyed when heated, since no stresses are generated in the gypsum mold.
- a defined flexible flat structure based on carbon fibers is used as the heating conductor, for example a carbon fiber felt mat or a carbon fiber fabric.
- carbon fibers with at least 95% C content are used, the carbon fibers should have a resistance of 1.3 to 2 ohms / m.
- the heating conductor in the plaster form is preferably operated with low voltage up to a maximum of 42 V in order to max. to achieve up to about 70 ° C heating of the carbon fiber sheet. This temperature can be reached within a few minutes. Depending on the quality and quantity of the carbon fiber fabric used, an output of up to 300 W / m 2 can be achieved as heating output.
- an energy source is one Low-voltage transformer with mains connection provided.
- the heatable absorbent gypsum mold according to the invention with an electrical heating conductor cast into the gypsum mold based on a carbon fiber sheet is used according to a further embodiment according to the invention for the production of ceramic bodies from slip using a slip casting process, in which the gypsum mold is accelerated to accelerate the formation of fragments of the slip during the execution of the slip casting process Applying a voltage to the electrical heating conductor cast into the plaster mold is heated to a temperature of 30 to 50 ° C. from the inside and via the free outer surface of the plaster mold, the moisture absorbed from the slip is released during the body formation time.
- Gypsum molds can achieve other positive effects that lead to significant improvements in the production of ceramic bodies from slip using slip casting processes. On the one hand, this is a faster formation of fragments of the ceramic slip. Furthermore, the moisture absorbed by the gypsum mold from the slurry can continuously flow over the free surface of the
- Gypsum mold avoided during the molding process and thus the entire production process is evened out.
- the invention of the direct heating of plaster molds for the slip casting process means an important further development of the conventional casting process for the ceramic industry, in particular sanitary parts. With the method according to the invention, it is possible to produce qualitatively improved plaster molds which enable up to 200 impressions to be made using the slip casting method.
- the uniformity of the temperature during the drying of the slip by penetrating the moisture into the gypsum mold heated from the inside results in an increase in the quality of the ceramic body.
- oxide ceramic slurries such as fused silica and aluminum oxide are cast at 35 ° C, and here by using a plaster mold, which according to the invention is heated to a temperature during the manufacture of the body at 50 ° C, a strength increase of 30% compared to the use of a not heated plaster mold reached.
- drying the ceramic body in the gypsum mold heated according to the invention reduces the breakage rate when the ceramic body is molded.
- the ceramic bodies produced have already achieved a significantly higher drying effect by producing them in a heated gypsum mold compared to an unheated gypsum mold, which increases their raw breaking strength. Cracks due to incorrect drying are largely eliminated.
- the energy costs for manufacturing slip-cast ceramic bodies by using gypsum molds which can be heated according to the invention and the drying method according to the invention since drying takes place only with a minimal amount, which is adapted to the ceramic body, ie its shape and size.
- a heated plaster mold G is shown, in which a heating conductor H is embedded from a carbon fiber sheet in the walls so that a uniform heating of the plaster mold G by connecting a corresponding voltage to the connections of the plaster mold led out Heating conductor is enabled.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Dispersion Chemistry (AREA)
- Producing Shaped Articles From Materials (AREA)
Abstract
The invention relates to an absorbent gypsum form (G), for the production of ceramic bodies from slurry, by means of a slurry casting method, which, according to the invention, may be heated (H). The invention further relates to a method for the production of the gypsum form and use of said gypsum form for the production of ceramic bodies from slurry.
Description
Beschreibung:Description:
Saugfähige Gipsform zum Herstellen von keramischen Körpern aus Schlicker und Herstellen von keramischen Körpern aus Schlicker unter Verwendung der saugfähigen GipsformAbsorbent gypsum mold for the production of ceramic bodies from slip and production of ceramic bodies from slip using the absorbent gypsum mold
Die Erfindung betrifft eine saugfähige Gipsform zum Herstellen von keramischen Körpern aus Schlicker mittels Schlickergussverfahren, ein Verfahren zum Herstellen der saugfähigen Gipsform sowie die Verwendung der saugfähigen Gipsform zum Herstellen von keramischen Körpern aus Schlicker.The invention relates to an absorbent gypsum mold for producing ceramic bodies from slip using slip casting processes, a method for producing the absorbent gypsum mold and the use of the absorbent gypsum mold for producing ceramic bodies from slip.
Keramische Massen werden je nach Wasseranteil mit unterschiedlichen Formgebungsverfahren zu den gewünschten Formkörpern verarbeitet. Keramische Gießmassen, auch Schlicker genannt, weisen einen erhöhten Wasseranteil mit verflüssigenden Agenzien auf, aus denen mit Hilfe saugfähiger Gipsformen kompliziertere Körper, wie Kannen, Reliefs, Sanitärgegenstände geformt werden können.Depending on the water content, ceramic masses are processed to the desired shaped bodies using different shaping processes. Ceramic casting compounds, also called slips, have an increased water content with liquefying agents, from which more complicated bodies, such as jugs, reliefs, sanitary objects, can be formed with the help of absorbent plaster molds.
In der keramischen Industrie ist es üblich, daß sanitärkeramische Teile wie Toiletten, Waschbecken und andere komplizierte Geometrien durch Schlickerguss in Gipsformen hergestellt werden. Diese saugfähig ausgebildeten Gipsformen entziehen dem keramischen Schlicker das Wasser und bilden einen Scherben durch die Entwässerung des Schlickers. Dieser Scherben lagert sich an der Oberfläche der Gipsform an und härtet durch weitere Entwässerung aus. Die Gipsformen müssen zudem zwischendurch
selbst entwässert werden, um wieder voll zum Einsatz zu gelangen. Je nach Größe der Gipsformen, die bis zu mehreren Hundert kg wiegen können, ist dies ein sehr aufwendiger Prozeß und die Saugleistung der Gipsformen läßt mit zunehmendem Alter nach. Es ist zur Zeit üblich, daß die Gipsformen in beheizten Räumen gehalten werden, so daß diese durch zirkulierende Umluft und eine sehr kostenaufwendige Konvektionsheizung des gesamten Arbeitsraumes getrocknet werden.In the ceramic industry, it is common for sanitary ceramic parts such as toilets, sinks and other complicated geometries to be made in plaster molds by slip casting. These absorbent gypsum molds extract the water from the ceramic slip and form a shard through the drainage of the slip. This cullet adheres to the surface of the plaster mold and hardens through further drainage. The plaster molds must also in between be dewatered in order to be fully used again. Depending on the size of the plaster molds, which can weigh up to several hundred kg, this is a very complex process and the suction power of the plaster molds decreases with increasing age. It is currently common for the plaster molds to be kept in heated rooms, so that they are dried by circulating air and very expensive convection heating of the entire work space.
Aus der US-PS 3228649 ist eine poröse Gipsform bekannt geworden, die mit zwei metallischen Elektroden ausgerüstet ist, um bei durch aufgenommene Feuchtigkeit ansteigender elektrischer Leitfähigkeit einen elektrischen Strom durch die Form zu leiten und die Feuchtigkeit wieder zu entfernen.From US-PS 3228649 a porous gypsum mold has become known which is equipped with two metallic electrodes in order to conduct an electrical current through the mold and remove the moisture again when electrical conductivity increases due to the moisture absorbed.
Der Erfindung liegt die Aufgabe zugrunde, das Herstellen von keramischen Körpern aus Schlicker, insbesondere auch komplizierter Geometrien und kleinerer Serien wirtschaftlicher zu gestalten.The invention has for its object to make the production of ceramic bodies from slip, in particular also complicated geometries and smaller series more economical.
Erfindungsgemäß wird hierzu eine saugfähige Gipsform zum Herstellen von keramischen Körpern aus Schlicker mittels Schlickergussverfahren vorgeschlagen, die dadurch gekennzeichnet ist, daß sie beheizbar mittels eines eingegossenen elektrischen Heizleiters auf Basis eines Kohlefaser- flächengebildes ausgebildet ist. Durch die Herstellung der Gipsform mit einem eingegossenen Heizleiter in Gestalt eines Kohlefaserflächengebildes, ist die Gipsform beheizbar und zwar bereits in statu nascendi, also während ihrer eigenen Herstellung und darüber hinaus auch bei späterer Benutzung als Arbeitsform für das Schlickergussverfahren.According to the invention, an absorbent gypsum mold for producing ceramic bodies from slip using slip casting processes is proposed, which is characterized in that it is heatable by means of a cast-in electrical heating conductor based on a carbon fiber sheet. By producing the gypsum mold with a cast-in heating conductor in the form of a carbon fiber sheet, the gypsum mold can be heated and is already in statu nascendi, i.e. during its own manufacture and, moreover, during later use as a working mold for the slip casting process.
Vorteilhafte Ausgestaltungen der Erfindung sind den kennzeichnenden Merkmalen der Ansprüche entnehmbar.
Die Erfindung ermöglicht eine schnelle und energiesparende Trocknung der Gipsformen bei ihrer Herstellung. Hierzu wird erfindungsgemäß vorgeschlagen, das Verfahren zum Herstellen von saugfähigen Gipsformen für die Herstellung von keramischen Körpern aus Schlicker derart weiterzubilden, daß elektrische Heizleiter auf Basis eines Kohlefaserflächengebildes in die die Gipsform bildende Form eingelegt und mit dem Gips umgössen werden und nach Beendigung des Gießvorganges durch Anlegen einer Spannung an das Kohlefaserflächengebilde eine Temperatur im Bereich von 30 bis 70°C in der Gipsform erzeugt wird, wobei die Gipsform trocknet.Advantageous refinements of the invention can be found in the characterizing features of the claims. The invention enables quick and energy-saving drying of the plaster molds during their manufacture. For this purpose, it is proposed according to the invention to further develop the process for producing absorbent gypsum molds for the production of ceramic bodies from slip in such a way that electrical heating conductors based on a carbon fiber sheet are inserted into the mold forming the gypsum mold and cast with the gypsum and after the casting process has ended by applying a voltage on the carbon fiber sheet a temperature in the range of 30 to 70 ° C is generated in the plaster mold, the plaster mold dries.
Als Heizleiter werden bevorzugt flexible Kohlefaserflächengebilde eingesetzt, die auch den Vorteil aufweisen, daß Kohlefasern bei der Erwärmung einen negativen Ausdehnungskoeffizienten aufweisen, so daß bei Erwärmung die Gipsform nicht zerstört werden kann, da keine Spannungen in der Gipsform erzeugt werden.Flexible carbon fiber sheets are preferably used as heating conductors, which also have the advantage that carbon fibers have a negative expansion coefficient when heated, so that the gypsum mold cannot be destroyed when heated, since no stresses are generated in the gypsum mold.
Als Heizleiter wird erfindungsgemäß ein definiertes flexibles Flächengebilde auf Basis Kohlenfasern eingesetzt, beispielsweise eine Kohlefaserfilzmatte oder ein Kohlefasergewebe. Hierbei werden Kohlefasern mit mindestens 95 % C-Gehalt eingesetzt, wobei die Kohlefasern einen Widerstand von 1 ,3 bis 2 Ohm/m aufweisen sollten. Bevorzugt werden auch Kohlefasergewebe, bei denen möglichst viele Kohlefasern in einer Achse angeordnet sind, wodurch ein hoher Wirkungsgrad der Stromleitung und damit der erzeugbaren thermischen Energie erreicht wird.According to the invention, a defined flexible flat structure based on carbon fibers is used as the heating conductor, for example a carbon fiber felt mat or a carbon fiber fabric. Here, carbon fibers with at least 95% C content are used, the carbon fibers should have a resistance of 1.3 to 2 ohms / m. Also preferred are carbon fiber fabrics in which as many carbon fibers as possible are arranged in one axis, as a result of which a high efficiency of the power line and thus of the thermal energy that can be generated is achieved.
Der Heizleiter in der Gipsform wird bevorzugt mit Niederspannung bis zu höchstens 42 V betrieben, um max. bis zu etwa 70°C Erwärmung des Kohlefaserflächengebildes zu erreichen. Diese Temperatur kann innerhalb weniger Minuten erreicht werden. Je nach Qualität und Quantität des eingesetzten Kohlefaserflächengebildes kann eine Leistung bis zu 300 W/m2 als Heizleistung erreicht werden. Als Energiequelle ist ein die
Niederspannung liefernder Trafo mit Netzanschluß vorgesehen. Die erfindungsgemäße beheizbare saugfähige Gipsform mit einem in die Gipsform eingegossenen elektrischen Heizleiter auf Basis eines Kohlefaserflächengebildes wird gemäß einer weiteren erfindungsgemäßen Ausbildung zum Herstellen von keramischen Körpern aus Schlicker mittels Schlickergussverfahren eingesetzt, bei dem zur Beschleunigung der Scherbenbildung des Schlickers während der Durchführung des Schlickergussverfahrens die Gipsform durch Anlegen einer Spannung an den in die Gipsform eingegossenen elektrischen Heizleiter auf eine Temperatur von 30 bis 50°C von innen her aufgeheizt wird und über die freie äußere Oberfläche der Gipsform, die aus dem Schlicker aufgenommene Feuchtigkeit, während der Scherbenbildungszeit abgegeben wird.The heating conductor in the plaster form is preferably operated with low voltage up to a maximum of 42 V in order to max. to achieve up to about 70 ° C heating of the carbon fiber sheet. This temperature can be reached within a few minutes. Depending on the quality and quantity of the carbon fiber fabric used, an output of up to 300 W / m 2 can be achieved as heating output. As an energy source is one Low-voltage transformer with mains connection provided. The heatable absorbent gypsum mold according to the invention with an electrical heating conductor cast into the gypsum mold based on a carbon fiber sheet is used according to a further embodiment according to the invention for the production of ceramic bodies from slip using a slip casting process, in which the gypsum mold is accelerated to accelerate the formation of fragments of the slip during the execution of the slip casting process Applying a voltage to the electrical heating conductor cast into the plaster mold is heated to a temperature of 30 to 50 ° C. from the inside and via the free outer surface of the plaster mold, the moisture absorbed from the slip is released during the body formation time.
Durch den erfindungsgemäßen Einsatz der beheizbaren saugfähigen Gipsformen ist eine gleichmäßig Aufheizung dieser Gipsformen alsBy using the heatable absorbent gypsum molds according to the invention, these gypsum molds are evenly heated as
Arbeitsformen im Schlickergussverfahren während der Produktion von keramischen Körpern aus Schlicker möglich. Durch das direkte Beheizen derForms of work in slip casting process possible during the production of ceramic bodies from slip. By directly heating the
Gipsformen lassen sich weitere positive Effekte erzielen, die zu wesentlichen Verbesserungen bei der Produktion von keramischen Körpern aus Schlicker mittels Schlickergussverfahren führen. Dies ist zum einen eine schnellere Scherbenbildung des keramischen Schlickers. Des weiteren kann die von der Gipsform aufgenommene Feuchtigkeit aus dem Schlicker während der Scherbenbildungzeit kontinuierlich über die freie Oberfläche derGypsum molds can achieve other positive effects that lead to significant improvements in the production of ceramic bodies from slip using slip casting processes. On the one hand, this is a faster formation of fragments of the ceramic slip. Furthermore, the moisture absorbed by the gypsum mold from the slurry can continuously flow over the free surface of the
Gipsform wieder abgegeben werden. In Folge dieser kontinuierlichen Verdunstung des aufgenommenen Wassers wird eine Uberfeuchtung derPlaster mold can be released again. As a result of this continuous evaporation of the absorbed water, over-humidification of the
Gipsform während des Formgebungsprozesses vermieden und damit der gesamte Produktionsvorgang vergleichmäßigt.Gypsum mold avoided during the molding process and thus the entire production process is evened out.
Durch die Wärmeerzeugung in der Gipsform selbst infolge des eingegossenen Heizleiters entfällt eine sehr energie- und kostenaufwendige Konvektionsheizung des gesamten, die Gipsformen umgebenden Arbeitsraumes.
Darüber hinaus entfallen Produktionsunterbrechnungen mit Rücktrocknungs- zyklen bedingt durch überfeuchtete Gipsformen während der Produktion.The generation of heat in the plaster mold itself, as a result of the cast-in heating conductor, eliminates the need for very energy-intensive and costly convection heating of the entire work space surrounding the plaster molds. In addition, there are no production interruptions with re-drying cycles due to over-moistened plaster molds during production.
Die Erfindung der direkten Beheizung von Gipsformen für das Schlickergussverfahren bedeutet für die keramische Industrie, insbesondere Sanitärteile eine wichtige Weiterentwicklung des konventionellen Gießverfahrens. Mit dem erfindungsgemäßen Verfahrens ist es möglich, qualitativ verbesserte Gipsformen herzustellen, die bis zu 200 Abformungen nach dem Schlickergussverfahren ermöglichen.The invention of the direct heating of plaster molds for the slip casting process means an important further development of the conventional casting process for the ceramic industry, in particular sanitary parts. With the method according to the invention, it is possible to produce qualitatively improved plaster molds which enable up to 200 impressions to be made using the slip casting method.
In der Vergangenheit ist die verfahrenstechnische Entwicklung zur Herstellung keramischer Körper aus keramischen Massen in Richtung Mittel- und Hochdruckgießverfahren gegangen. Mit der vorliegenden Erfindung wird das preiswerte Schlickergussverfahren erheblich verbessert.In the past, procedural development for the production of ceramic bodies from ceramic masses has moved towards medium and high pressure casting processes. With the present invention, the inexpensive slip casting process is considerably improved.
Durch die Vergleichmäßigung der Temperatur während des Trocknens des Schlickers durch Eindringen der Feuchtigkeit in die von innen her beheizte Gipsform wird eine Qualitätssteigerung des keramischen Scherbens erreicht. Beispielsweise werden oxidische keramische Schlicker wie Fused-Silica und Aluminiumoxid bei 35 °C vergossen, und hier durch Einsatz einer Gipsform, die erfindungsgemäß auf eine Temperatur während der Herstellung des Scherbens auf 50°C erwärmt wird, eine Festigkeitssteigerung von 30 % gegenüber dem Einsatz einer nicht beheizten Gipsform erreicht.The uniformity of the temperature during the drying of the slip by penetrating the moisture into the gypsum mold heated from the inside results in an increase in the quality of the ceramic body. For example, oxide ceramic slurries such as fused silica and aluminum oxide are cast at 35 ° C, and here by using a plaster mold, which according to the invention is heated to a temperature during the manufacture of the body at 50 ° C, a strength increase of 30% compared to the use of a not heated plaster mold reached.
Darüber hinaus sinkt durch das Trocknen des keramischen Scherbens in der erfindungsgemäß beheizten Gipsform die Bruchrate beim Ausformen der keramischen Körper. Die hergestellten keramischen Körper haben bereits einen wesentlich höheren Trocknungseffekt durch Herstellen in einer beheizten Gipsform gegenüber einer unbeheizten Gipsform erreicht, wodurch sich ihre Rohbruchfestigkeit erhöht. Auch Rißbildungen infolge falschen Trocknens entfallen weitgehend. Insgesamt können die Energiekosten für die Herstellung schlickergegossener keramischer Körper
durch Einsatz von erfindungsgemäß beheizbarer Gipsformen und das erfindungsgemäße Trocknungsverfahren wesentlich reduziert werden, da nur mit einem minimalen, dem keramischen Körper, d. h. dessen Form und Größe angepaßt, getrocknet wird. Darüber hinaus ist es auch möglich, sehr gleichmäßig sowohl große Gipsformen als auch große keramische Körper zu trocknen. In der beigefügten schematischen Darstellung der Figur 1 ist eine beheizte Gipsform G dargestellt, in welche ein Heizleiter H aus einem Kohlefaserflächengebilde in die Wände so eingebettet ist, daß eine gleichmäßige Beheizung der Gipsform G durch Anschluß einer entsprechenden Spannung an die aus der Gipsform herausgeführten Anschlüsse des Heizleiters ermöglicht ist.
In addition, drying the ceramic body in the gypsum mold heated according to the invention reduces the breakage rate when the ceramic body is molded. The ceramic bodies produced have already achieved a significantly higher drying effect by producing them in a heated gypsum mold compared to an unheated gypsum mold, which increases their raw breaking strength. Cracks due to incorrect drying are largely eliminated. Overall, the energy costs for manufacturing slip-cast ceramic bodies by using gypsum molds which can be heated according to the invention and the drying method according to the invention, since drying takes place only with a minimal amount, which is adapted to the ceramic body, ie its shape and size. In addition, it is also possible to dry both large plaster molds and large ceramic bodies very evenly. In the attached schematic representation of Figure 1, a heated plaster mold G is shown, in which a heating conductor H is embedded from a carbon fiber sheet in the walls so that a uniform heating of the plaster mold G by connecting a corresponding voltage to the connections of the plaster mold led out Heating conductor is enabled.
Claims
1 . Saugfähige Gipsform zum Herstellen von keramischen Körpern aus Schlicker mittels Schlickergussverfahren, dadurch gekennzeichnet, daß sie beheizbar mittels eines eingegossenen elektrischen Heizleiters auf Basis eines Kohlefaserflächengebildes ausgebildet ist.1 . Absorbent gypsum mold for the production of ceramic bodies from slip using slip casting processes, characterized in that it is heatable by means of a cast-in electrical heating conductor based on a carbon fiber fabric.
2. Saugfähige Gipsform nach Anspruch 1 , dadurch gekennzeichnet, daß der elektrische Heizleiter eine Heizleistung von 50 bis 300 W/m2 aufweist.2. Absorbent plaster mold according to claim 1, characterized in that the electrical heating conductor has a heating power of 50 to 300 W / m 2 .
3. Saugfähige Gipsform nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß Kohlefasern mit einem Widerstand von 1 ,2 bis 2 Ohm/m für das3. Absorbent plaster mold according to claim 1 or 2, characterized in that carbon fibers with a resistance of 1, 2 to 2 ohms / m for the
Kohlefaserflächengebilde eingesetzt sind.Carbon fiber fabrics are used.
4. Saugfähige Gipsform nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß als Heizleiter ein Kohlefaserflächengebilde eingesetzt ist, bei dem möglichst viele Kohlefasern in einer Achse angeordnet sind, so daß ein hoher Wirkungsgrad der Stromleitung und damit der erzeugbaren thermischen Energie erzielbar ist.4. Absorbent plaster mold according to one of claims 1 to 3, characterized in that a carbon fiber sheet is used as the heating conductor, in which as many carbon fibers are arranged in one axis, so that a high efficiency of the power line and thus the thermal energy that can be generated can be achieved.
5. Saugfähige Gipsform nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der Heizleiter mit Niederspannung bis zu 42 V arbeitet, wobei das Kohlefaserflächengebilde bis auf etwa 70°C aufheizbar ist.5. Absorbent plaster mold according to one of claims 1 to 4, characterized in that the heating conductor operates at low voltage up to 42 V, the carbon fiber sheet material being heatable to about 70 ° C.
6. Saugfähige Gipsform nach einem der Ansprüche 1 bis 5 dadurch gekennzeichnet, daß die Temperatur und Heizleistung des6. Absorbent plaster mold according to one of claims 1 to 5, characterized in that the temperature and heating power of the
Kohlefaserflächengebildes mittels einer Steuerung der Spannung einstellbar ist. Carbon fiber sheet is adjustable by controlling the tension.
7. Verfahren zum Herstellen von saugfähigen Gipsformen für die Herstellung von keramischen Körpern aus Schlicker mittels Schlickergussverfahren dadurch gekennzeichnet, daß elektrische Heizleiter auf Basis eines Kohlefaserflächengebildes in die die Gipsform bildende Form eingelegt und mit dem Gips umgössen werden und nach7. A process for the production of absorbent gypsum molds for the production of ceramic bodies from slip using slip casting processes, characterized in that electrical heating conductors based on a carbon fiber sheet are inserted into the mold forming the plaster mold and cast with the plaster and after
Beendigung des Gießvorganges durch Anlegen einer Spannung an das Kohlefaserflächengebilde eine Temperatur im Bereich von 30 bis 70 °C in der Gipsform erzeugt wird, wobei die Gipsform von innen her erwärmt wird und trocknet.Completion of the casting process by applying a voltage to the carbon fiber sheet a temperature in the range of 30 to 70 ° C is generated in the plaster mold, the plaster mold is heated and dried from the inside.
8. Verwendung einer beheizbaren und saugfähigen Gipsform mit einem in die Gipsform eingegossenen elektrischen Heizleiter auf Basis eines Kohlefaserflächengebildes zum Herstellen von keramischen Körpern aus Schlicker mittels Schlickergussverfahren, bei dem zur Beschleunigung der Scherbenbildung des Schlickers während der Durchführung des8. Use of a heatable and absorbent gypsum mold with an electrical heating conductor cast into the gypsum mold on the basis of a carbon fiber sheet for the production of ceramic bodies from slip using a slip casting process, in which to accelerate the formation of shards of the slip during the implementation of the
Schlickergussverfahrens die Gipsform durch Anlegen einer Spannung an den in die Gipsform eingegossenen elektrischen Heizleiter auf eine Temperatur von 30 bis 70°C von innen her aufgeheizt und über die freie äußere Oberfläche der Gipsform, die aus dem Schlicker aufgenommene Feuchtigkeit, während der Scherbenbildungszeit abgegeben wird. Slip casting process, the gypsum mold is heated from the inside to a temperature of 30 to 70 ° C. by applying a voltage to the electrical heating conductor cast into the gypsum mold, and the moisture absorbed from the slurry is released during the body formation process via the free outer surface of the gypsum mold.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU2001239233A AU2001239233A1 (en) | 2000-01-29 | 2001-01-29 | Absorbent gypsum form for the production of ceramic bodies from slurry and the production of ceramic bodies from slurry by use of the absorbent gypsum form |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2000103945 DE10003945C2 (en) | 2000-01-29 | 2000-01-29 | Absorbent gypsum mold for the production of ceramic bodies from slip and production of ceramic bodies from slip using the absorbent gypsum mold |
| DE10003945.6 | 2000-01-29 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2001054874A1 true WO2001054874A1 (en) | 2001-08-02 |
Family
ID=7629201
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/EP2001/000940 WO2001054874A1 (en) | 2000-01-29 | 2001-01-29 | Absorbent gypsum form for the production of ceramic bodies from slurry and the production of ceramic bodies from slurry by use of the absorbent gypsum form |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU2001239233A1 (en) |
| DE (1) | DE10003945C2 (en) |
| WO (1) | WO2001054874A1 (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE910154C (en) * | 1951-01-10 | 1954-04-29 | Gottfried Cremer Dr | Compression mold |
| US3978183A (en) * | 1974-06-24 | 1976-08-31 | Sybron Corporation | Method of filter molding and electrical heating unit made thereby |
| EP0004188A1 (en) * | 1978-03-09 | 1979-09-19 | Sekisui Kagaku Kogyo Kabushiki Kaisha | Heating unit capable of generating heat upon passing an electric current therethrough, method for producing such a heating unit, and heating systems comprising such a heating unit |
| WO1987003158A1 (en) * | 1985-11-14 | 1987-05-21 | A. Ahlstrom Corporation | Electric resistance sheet and method of producing such |
| SU1399124A1 (en) * | 1986-07-09 | 1988-05-30 | Украинский Научно-Исследовательский Институт Фарфоро-Фаянсовой Промышленности | Method of producing ceramic articles |
| WO1997035698A1 (en) * | 1996-03-27 | 1997-10-02 | British Ceramic Research Limited | Slip casting |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL272562A (en) * | 1960-12-27 |
-
2000
- 2000-01-29 DE DE2000103945 patent/DE10003945C2/en not_active Expired - Fee Related
-
2001
- 2001-01-29 WO PCT/EP2001/000940 patent/WO2001054874A1/en active Application Filing
- 2001-01-29 AU AU2001239233A patent/AU2001239233A1/en not_active Abandoned
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE910154C (en) * | 1951-01-10 | 1954-04-29 | Gottfried Cremer Dr | Compression mold |
| US3978183A (en) * | 1974-06-24 | 1976-08-31 | Sybron Corporation | Method of filter molding and electrical heating unit made thereby |
| EP0004188A1 (en) * | 1978-03-09 | 1979-09-19 | Sekisui Kagaku Kogyo Kabushiki Kaisha | Heating unit capable of generating heat upon passing an electric current therethrough, method for producing such a heating unit, and heating systems comprising such a heating unit |
| WO1987003158A1 (en) * | 1985-11-14 | 1987-05-21 | A. Ahlstrom Corporation | Electric resistance sheet and method of producing such |
| SU1399124A1 (en) * | 1986-07-09 | 1988-05-30 | Украинский Научно-Исследовательский Институт Фарфоро-Фаянсовой Промышленности | Method of producing ceramic articles |
| WO1997035698A1 (en) * | 1996-03-27 | 1997-10-02 | British Ceramic Research Limited | Slip casting |
Non-Patent Citations (1)
| Title |
|---|
| SOVIET INVENTIONS ILLUSTRATED Week 198848, Derwent World Patents Index; AN 1988-345251, XP002167320 * |
Also Published As
| Publication number | Publication date |
|---|---|
| DE10003945A1 (en) | 2001-08-23 |
| AU2001239233A1 (en) | 2001-08-07 |
| DE10003945C2 (en) | 2001-12-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3551358B1 (en) | Method and mold tool or core tool for producing molds or cores | |
| DE3936904A1 (en) | METHOD FOR PRODUCING ALSO LARGE-SIDED PANELS FROM CERAMIC MATERIAL WITH INCREASED MECHANICAL PROPERTIES | |
| DE1904381C3 (en) | Process for producing carbon bodies | |
| DE102018204672A1 (en) | Process for producing a honeycomb structure | |
| DE10003945C2 (en) | Absorbent gypsum mold for the production of ceramic bodies from slip and production of ceramic bodies from slip using the absorbent gypsum mold | |
| DE102018204670A1 (en) | Process for producing a honeycomb structure | |
| DE3942528A1 (en) | METHOD FOR PRODUCING A FIBER LIGHT STONE AND FIBER LIGHT STONE | |
| DE2905481C2 (en) | Process for the preparation of a rare earth chromite element containing ions of divalent metals | |
| DE837287C (en) | Process for heating and sintering dental prosthetic plastics for the purpose of their deformation | |
| CH224046A (en) | Voltage dependent resistance. | |
| EP0487924A2 (en) | Process for manufacturing ceramic mouldings and/or profile members | |
| AT250231B (en) | Method and device for heating ceramic materials pressed by means of an extrusion press | |
| DE2361304A1 (en) | Moulded ceramic article prodn - by freezing slip in undercooled mould, demoulding, and dehydrating | |
| DE10326711B4 (en) | Device for drying a lining mass | |
| DE854404C (en) | Process and device for the production of objects from thermoplastic or thermosetting materials | |
| DE1683784A1 (en) | Method and device for the production of molded parts | |
| DE10038704A1 (en) | Process for drying ceramic bodies comprises using a vacuum chamber which is evacuated to a low pressure corresponding to the boiling point of the water contained in the body | |
| DE102004049865A1 (en) | Apparatus and method for printing, in particular for printing microstructures | |
| DE1459307A1 (en) | Method and device for the manufacture of ceramic products | |
| DE102004015378A1 (en) | Block making machine comprises a heat source which is independent of the die assembly, and serves for heating at least one contact surface of the die assembly | |
| DE856928C (en) | Device for the electrical heating of machine parts | |
| DE4341533A1 (en) | Pressure casting of ceramic article with reduced filtration time or casting pressure | |
| DE10223250B4 (en) | Device for the production of molded articles from fiber-reinforced ceramic materials | |
| DE2746867A1 (en) | METHOD OF MANUFACTURING CERAMIC OBJECTS BY POURING WITH MATERIAL SLUDGE | |
| DE3329675A1 (en) | METHOD AND DEVICE FOR PRODUCING A CERAMIC DIMENSIONAL SHEET |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AK | Designated states |
Kind code of ref document: A1 Designated state(s): AU BR CA CN CZ HU IN JP MX PL RU US ZA |
|
| AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR |
|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
| DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
| 122 | Ep: pct application non-entry in european phase | ||
| NENP | Non-entry into the national phase |
Ref country code: JP |