EP0124801A2 - Method of making precision castings by using the plaster moulding process - Google Patents
Method of making precision castings by using the plaster moulding process Download PDFInfo
- Publication number
- EP0124801A2 EP0124801A2 EP84104215A EP84104215A EP0124801A2 EP 0124801 A2 EP0124801 A2 EP 0124801A2 EP 84104215 A EP84104215 A EP 84104215A EP 84104215 A EP84104215 A EP 84104215A EP 0124801 A2 EP0124801 A2 EP 0124801A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- mold
- molding
- poured
- water
- model
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000465 moulding Methods 0.000 title claims abstract description 40
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 4
- 238000005495 investment casting Methods 0.000 title description 3
- 239000011505 plaster Substances 0.000 title description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 17
- 150000001875 compounds Chemical class 0.000 claims abstract description 14
- 238000005266 casting Methods 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 7
- 229910052751 metal Inorganic materials 0.000 claims abstract description 5
- 239000002184 metal Substances 0.000 claims abstract description 5
- 239000000203 mixture Substances 0.000 claims description 7
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- 239000011230 binding agent Substances 0.000 claims description 3
- 239000003365 glass fiber Substances 0.000 claims description 3
- 238000001354 calcination Methods 0.000 claims 1
- ZOMBKNNSYQHRCA-UHFFFAOYSA-J calcium sulfate hemihydrate Chemical compound O.[Ca+2].[Ca+2].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O ZOMBKNNSYQHRCA-UHFFFAOYSA-J 0.000 claims 1
- 239000010440 gypsum Substances 0.000 abstract description 7
- 229910052602 gypsum Inorganic materials 0.000 abstract description 7
- 238000005058 metal casting Methods 0.000 description 7
- 239000004744 fabric Substances 0.000 description 3
- 239000000835 fiber Substances 0.000 description 3
- 239000011490 mineral wool Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000004568 cement Substances 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- WYTGDNHDOZPMIW-RCBQFDQVSA-N alstonine Natural products C1=CC2=C3C=CC=CC3=NC2=C2N1C[C@H]1[C@H](C)OC=C(C(=O)OC)[C@H]1C2 WYTGDNHDOZPMIW-RCBQFDQVSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000010425 asbestos Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 239000011152 fibreglass Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012778 molding material Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 229910052895 riebeckite Inorganic materials 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/12—Treating moulds or cores, e.g. drying, hardening
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
- B22D27/15—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using vacuum
Definitions
- the present invention relates to a process for the production of castings with sharp detail reproduction and high measuring accuracy according to the gypsum molding process: and the precision casting produced with this molding process.
- Gypsum molding processes have long been got: t.
- the molding material in these processes mainly consists of gypsum.
- Other components can include sand, cement, sodium silicate, asbestos, etc. be.
- the gypsum has the function of a binder and can also be used in higher temperature ranges.
- precision outlets cannot be produced using this process, even if the vacuum molding process is used.
- a powder mixture which contains alpha-calcium sulfate hemihydrate (binder) as essential constituents, optionally also cement and chamotte and / or quartz powder as filler. Sufficient water is added to this mixture so that sufficient gas permeability is achieved, which applies to a pore volume of at least 25%.
- the required smooth surface of the mold is achieved with a defined grain distribution.
- Auxiliaries such as setting accelerators, retarders, glass fibers, etc. can be added to the mixture.
- a key feature of the new process is that that the adhering water of the molding compound is removed by pressure drainage. In this way, considerable amounts of energy can be saved, so that the casting process can now also be used for large-area precision castings and series castings.
- the evacuation during metal casting additionally reduces the energy requirement, it being further advantageous that pressure drainage and evacuation can be carried out using the same system (drainage device).
- g Prior to molding, g is the USS, a drain in the form of a porous hose-applied or a perforated fiberglass mat over theboxformende original, which is coated with a release agent.
- this is expediently done with a close-meshed wire mesh, which is attached at a distance of approx. 10 mm above the original and is slightly flexible.
- the hose is then attached to the wire in a lump-like manner and led outward at one end through the mold frame or through the mold. No wire mesh is required when using perforated glass fiber mats.
- the molding compound is poured into the prepared molding box.
- an upper or lower box or multi-part molds can be produced.
- the molding compositions (negative forms) are lifted immediately after solidification from the original and to remove the water to the P reß Kunststoff für an institute..Das squeezing the water is advantageously carried out with a pressure increase of 0.1 bar per minute, and in fact until about 2 bar are reached. For complete Water removal will maintain this pressure for a period of time, such as 10 to 20 minutes. In most cases, 10 to 20 minutes is enough.
- the pore space formed by the water squeezing is essential for the subsequent metal casting.
- the negative molds After pressing, the negative molds remain open and stored for approx. 2 hours until they have set completely. A further 24-hour drying at 60 - 100 ° C may be necessary for larger molds. However, it is also necessary if a sufficient vacuum performance cannot be achieved in the subsequent metal casting.
- the vacuum lines are connected to the compressed air nozzle (s). This can be done using a direct-working vacuum pump with sufficient performance, as well as using a pre-evacuated vessel.
- the negative mold is evacuated and the melt is poured in immediately.
- the maximum amount of gas is 4 l / qdm mold surface.
- the rear wall thickness of the mold is greater than the distance between the hose and the work surface. In most cases a double to three times the wall thickness is sufficient.
- a fitting plastic original (model), size approx. 20 x 10 x 8 cm, was coated with a wafer-thin oil film as a separating agent ur: d in a mold box with the internal dimensions 24 x 14 x 11 cm.
- An easily deformable wire mesh with a mesh size of approx. 2 - 3 cm was adapted to this original surface.
- a porous fabric tube of 8 mm diameter was connected to the wire mesh with a lateral distance of about 2 cm, the tube end was connected to the pipe socket attached to the molding box and the drainage device was fixed about 1 cm above the model.
- the mold box with the negative model for the following cast aluminum was connected to a vacuum line. A negative pressure of -0.9 bar was established.
- the molten aluminum alloy (720 ° C) was filled into the evacuated mold. The casting was demolded after the alloy had completely solidified, which was the case after about 20 minutes. The negative mold could be used for three more metal castings.
- Example 1 a perforated mineral wool fiber mat with a thickness of 2 cm was used.
- the hole diameter was 1.5 cm, the distance from hole to hole was 2-3 cm.
- the molding box was filled with the casting compound approx. 1 cm above the original and then the mineral wool fiber mat was fixed at a distance of approx. 1 cm above the original surface and the molding box was then filled up. Breaking out, evacuation and metal casting were carried out as in Example 1.
- Parts 1a of the molding box are designated by 1a) and 1b) in the figure.
- the model 7 lying in the box half 1a) is with the wire mesh fabric 6 on which the porous fabric tube 2 is arranged in a serpentine manner.
- the compressed gas is introduced through the nozzle at 4 and the vacuum is drawn off through the same nozzle.
- the molding compound is indicated with the number 3.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Producing Shaped Articles From Materials (AREA)
- Mold Materials And Core Materials (AREA)
- Dental Preparations (AREA)
Abstract
Verfahren zur Herstellung von Gußteilen mit scharfer Detailwiedergabe und hoher Meßgenauigkeit nach dem Gips-Formverfahren, bei dem das abzubildende Modell mit einer Drainagevorrichtung, die mindestens je einen Zu- bzw. Ablauf außerhalb des Formkastens aufweist, versehen wird und die in den Formkasten gegossene Formmasse erstarren gelassen wird. Das Wasser aus der erstarrten Formmasse wird nach Entfernung des Modells durch Einleiten von Druckgas herausgepreßt und die vom Modell abgelöste Form nach Trocknung an eine Vakuumleitung angeschlossen und evakuiert. Die Metallschmelze wird anschließend unter Beibehaltung des Vakuums in die Form gegossen und erstarren gelassen.Process for the production of castings with sharp detail reproduction and high measuring accuracy according to the gypsum molding process, in which the model to be imaged is provided with a drainage device, which has at least one inlet or outlet outside the molding box, and solidify the molding compound poured into the molding box is left. After removal of the model, the water from the solidified molding compound is pressed out by introducing compressed gas, and the mold detached from the model is connected to a vacuum line after drying and evacuated. The molten metal is then poured into the mold while maintaining the vacuum and allowed to solidify.
Description
Gegenstand der vorliegenden Erfindung ist ein Verfahren zur Herstellung von Gußteilen mit scharfer Detailwiedergabe und hoher Meßgenauigkeit nach dem Gips - Formverfahrer: sowie der mit diesem Formverfahren hergestellte Präzisionsgtß.The present invention relates to a process for the production of castings with sharp detail reproduction and high measuring accuracy according to the gypsum molding process: and the precision casting produced with this molding process.
Gips - Formverfahren sind schon seit langem bekam:t. Der Formstoff besteht bei diesen-Verfahren in der Hauptsache aus Gips. Weitere Bestandteile können Sand, Zement, Natriumsilikat, Asbest u.a. sein. In derartigen Mischungen hat der Gips die Funktion eines Bindemittels und ist auch in höheren Temperaturbereichen einsetzbar. Präzisionsaüsse können jedoch nach diesem Verfahren nicht hergestellt werden, und zwar auch dann nicht, wenn nach dem Vakuum-Formverfahren gearbeitet wird.Gypsum molding processes have long been got: t. The molding material in these processes mainly consists of gypsum. Other components can include sand, cement, sodium silicate, asbestos, etc. be. In such mixtures, the gypsum has the function of a binder and can also be used in higher temperature ranges. However, precision outlets cannot be produced using this process, even if the vacuum molding process is used.
Die Statistik zeigt, daß ein hoher Anteil der Gußserien mit Formsanden hergestellt wird. Die sich dabei ausbildende materialbedingte Gußoberfläche bringt jedoch zwangsläufig einen hohen Nachbearbeitungsaufwand, der sehr kostenintensiv ist und heute als nicht mehr vertretbar angesehen wird.Statistics show that a high proportion of the cast series is made with molding sands. However, the material-related casting surface that forms inevitably entails a high amount of post-processing, which is very cost-intensive and is no longer considered acceptable today.
Es stellte sich somit die Aufgabe, ein Formverfahren zu finden, das weder die Nachteile des Sand - Formverfahrens noch die des Gips - Formverfahrens zeigt.It was therefore the task of finding a molding process which did not show the disadvantages of the sand molding process or that of the gypsum molding process.
Überraschenderweise kann die gestellte Aufgabe derart gelöst werden, daß
- a) das abzubildende und mit einem Trennmittel beschichtete Modell mit einer Drainagevorrichtung, die mindestens je einen Zu- bzw. Ablauf außerhalb des Formkastens aufweist, versehen wird,
- b) die Formmasse in den Formkasten gegossen und erstarren gelassen wird,
- c) das Wasser der erstarrten Formmasse nach Entfernung des Modells durch Einleiten von Druckgas herausgepreßt wird und die vom Modell abaelöste Form nach Trocknung
- d) an eine Vakuumleitung angeschlossen und evakuiert wird, und daß
- e) die Metallschmelze unter Beibehaltung des Vakuums in die Form gegossen und erstarren gelassen wird.
- a) the one to be imaged and coated with a release agent Model is provided with a drainage device, which has at least one inlet or outlet outside the molding box,
- b) the molding compound is poured into the molding box and allowed to solidify,
- c) the water of the solidified molding compound is removed after the model has been removed by introducing compressed gas and the mold detached from the model after drying
- d) connected to a vacuum line and evacuated, and that
- e) the molten metal is poured into the mold while maintaining the vacuum and allowed to solidify.
Ein Brennen der Gipsformen bei Temperaturen von 400 bis 800°C ist bei dem neuen Verfahren nicht erforderlich. Damit können erhebliche Enereiemengen eingespart werden.Firing the plaster molds at temperatures of 400 to 800 ° C is not necessary with the new process. This can save considerable amounts of energy.
Zur Herstellung der Gipsformen wird eine Pulvermischung verwendet, die als wesentliche Bestandteile alpha-Calciumsulfat-Halbhydrat ( Bindemittel), gegebenenfalls noch Zement und Schamotte und/oder Quarzmehl als Füllstoff enthält. Dieser Mischung wird soviel Wasser zugesetzt, daß eine ausreichende Gasdurchlässigkeit erzielt wird, was auf ein Porenvolumen von mindestens 25 % zutrifft. Mit einer definierten Kornverteilung wird die erforderliche glatte Oberfläche der Form erzielt. Hilfsstoffe wie Abbindebeschleuniger, Verzögerer, Glasfasern u.a., können der Mischung beigegeben werden.To produce the gypsum molds, a powder mixture is used which contains alpha-calcium sulfate hemihydrate (binder) as essential constituents, optionally also cement and chamotte and / or quartz powder as filler. Sufficient water is added to this mixture so that sufficient gas permeability is achieved, which applies to a pore volume of at least 25%. The required smooth surface of the mold is achieved with a defined grain distribution. Auxiliaries such as setting accelerators, retarders, glass fibers, etc. can be added to the mixture.
Ein wesentliches Kennzeichen des neuen Verfahrens besteht darin, daß das anhaftende Wasser der Formmasse durch Druckentwässerung entfernt wird. Auf diese Weise können beträchtliche Energiemengen eingespart werden, so daß das Gießverfahren nunmehr auch für großflächige Präzisionsgüsse und Seriengüsse einsetzbar ist. Durch die Evakuierung beim Metallguß wird der Energiebedarf zusätzlich herabgesetzt, wobei weiterhin vorteilhaft ist, daß Druckentwässerung und Evakuierung über das gleiche System ( Drainagevorrichtung ) vorgenommen werden können.A key feature of the new process is that that the adhering water of the molding compound is removed by pressure drainage. In this way, considerable amounts of energy can be saved, so that the casting process can now also be used for large-area precision castings and series castings. The evacuation during metal casting additionally reduces the energy requirement, it being further advantageous that pressure drainage and evacuation can be carried out using the same system (drainage device).
Anhand der nachstehenden Ausführungen wird nun das neue Verfahren noch näher erläutert.The new method will now be explained in more detail with reference to the explanations below.
Vor dem Formenguß wird über das abzuformende Original, das mit einem Trennmittel beschichtet wird, eine Drainage in Form eines porösen Schlauches oder-einer gelochten Glasfasermatte aufgebracht. Bei der Schlauchmethode erfolgt das zweckmäßigerweise mit einem engmaschigen Drahtgewebe, das in einem Abstand von ca. 10 mm über dem Original befestigt wird und leicht biegsam ist. Anschließend wird der Schlauch schla::igenförmig über das Drahtgewebe verteilt befestigt und mit einem Ende durch den Formrahmen bzw. durch die Kokulle nach außen geführt. Bei der Verwendung von gelochten Glasfasermatten wird kein Drahtgewebe benötigt.Prior to molding, g is the USS, a drain in the form of a porous hose-applied or a perforated fiberglass mat over the abzuformende original, which is coated with a release agent. In the hose method, this is expediently done with a close-meshed wire mesh, which is attached at a distance of approx. 10 mm above the original and is slightly flexible. The hose is then attached to the wire in a lump-like manner and led outward at one end through the mold frame or through the mold. No wire mesh is required when using perforated glass fiber mats.
Nach Anrühren wird die Formmasse in den vorbereiteten Formkasten gegossen. Je nach Formteil können ein Obe=- oder Unterkasten bzw. auch mehrteilige Formen hergestellt werden.After mixing, the molding compound is poured into the prepared molding box. Depending on the molded part, an upper or lower box or multi-part molds can be produced.
Die Formmassen( Negativformen ) werden nach dem Erstarren sofort vom Original abgehoben und zur Entfernung des Wassers an die Preßluftleitung angeschlossen..Das Auspressen des Wassers erfolgt vorteilhafterweise mit einem Druckanstieg von 0,1 bar pro Minute und zwar solange, bis ca. 2 bar erreicht sind. Zur vollständigen Wasserentfernung wird dieser Druck noch über einen Zeitraum beibehalten, etwa 10 bis 20 Minuten. In den meisten Fällen reichen 10 bis 20 Minuten aus. Der durch das Wasserauspressen gebildete Porenraum ist für den nachfolgenden Metallguß von wesentlicher Bedeutung. Nach dem Auspressen bleiben die Negativformen bis zum völligen Abbinden ca. 2 Stunden offen - gelagert stehen. Eine weitere 24-stündige Trocknung bei 60 - 100°C kann bei größeren Formen erforderlich sein. Sie ast jedoch auch notwendig, wenn eine ausreichende Vakuumleistung beim nachfolgenden Metallguß nicht erbracht werden kann.The molding compositions (negative forms) are lifted immediately after solidification from the original and to remove the water to the P reßluftleitung angeschlossen..Das squeezing the water is advantageously carried out with a pressure increase of 0.1 bar per minute, and in fact until about 2 bar are reached. For complete Water removal will maintain this pressure for a period of time, such as 10 to 20 minutes. In most cases, 10 to 20 minutes is enough. The pore space formed by the water squeezing is essential for the subsequent metal casting. After pressing, the negative molds remain open and stored for approx. 2 hours until they have set completely. A further 24-hour drying at 60 - 100 ° C may be necessary for larger molds. However, it is also necessary if a sufficient vacuum performance cannot be achieved in the subsequent metal casting.
Vor dem Metallguß wird (werden) an den (oder die) Druckluftstutzen die Vakuumleitungen angeschlossen. Dies kann sowohl über eine direkt arbeitende Vakuumpumpe mit ausreichender Leistung, wie auch über ein vorevakuiertes Gefäß erfolgen. Unmittelbar vor dem Metallguß wird die Negativform evakuiert und die Schmelze sofort eingegossen.Before the metal casting, the vacuum lines are connected to the compressed air nozzle (s). This can be done using a direct-working vacuum pump with sufficient performance, as well as using a pre-evacuated vessel. Immediately before the metal casting, the negative mold is evacuated and the melt is poured in immediately.
Bis zur Erstarrung der Schmelze wird die Evakuierung fortgesetzt.The evacuation continues until the melt solidifies.
Die maximale Gasmenge liegt bei 4 l/qdm Formoberfläche. Zur Reduzierung von Vakuumverlusten ist es bei dem erfindungsgemäßen Verfahren wesentlich, daß die rückwärtige Wanddicke der Form größer ist als der Abstand zwischen Schlauch und Arbeitsoberfläche beträgt. In den meisten Fällen reicht eine doppelte bis dreifache Wanddicke aus.The maximum amount of gas is 4 l / qdm mold surface. To reduce vacuum losses, it is essential in the method according to the invention that the rear wall thickness of the mold is greater than the distance between the hose and the work surface. In most cases a double to three times the wall thickness is sufficient.
Bei sorgfältiger Verarbeitung, vor allem gleichmäßiger Verteilung der Drainage, bilden sich sehr glatte Metalloberflächen aus, welche die aufgeführten technischen Vorteile bringen.With careful processing, especially even distribution of the drainage, very smooth metal surfaces are formed, which bring the technical advantages listed.
Zur Herstellung der Negativform wurde ein Armaturenkunststofforiginal (Modell), Größe ca. 20 x 10 x 8 cm, mit einem hauchdünnen Oelfilm als Trennmittel überzogen ur:d in einen Formkasten mit den Innenmaßen 24 x 14 x 11 cm eingelegt. Auf diese Originaloberfläche wurde ein leicht verformbares Drahtgewebe mit ca. 2 - 3 cm Maschenweite angepaßt. Nach dieser Anformung wurde auf das Drahtgewebe ein poröser Gewebeschlauch von 8 mm Durchmesser mit seitlichem Abstand von etwa 2 cm angebunden, das Schlauchende mit dem am Formkasten angebrachten Rohrstutzen verbunden und die Drainage-Einrichtung ca. 1 cm über dem Modell fixiert.To produce the negative mold, a fitting plastic original (model), size approx. 20 x 10 x 8 cm, was coated with a wafer-thin oil film as a separating agent ur: d in a mold box with the internal dimensions 24 x 14 x 11 cm. An easily deformable wire mesh with a mesh size of approx. 2 - 3 cm was adapted to this original surface. After this molding, a porous fabric tube of 8 mm diameter was connected to the wire mesh with a lateral distance of about 2 cm, the tube end was connected to the pipe socket attached to the molding box and the drainage device was fixed about 1 cm above the model.
Zum Füllen des vorbereiteten Formkastens wurden 5 kg eines Pulvergemisches, bestehend aus
Eine Minute nach dem Erstarrungsende der Formmasse - ermittelt durch Fingerdruck - wurde an den Rohrstutzen die-Preßluftleitung angeschlossen. Der Anfangsdruck betrug 0,2 bar, die Drucksteigerung 0.01 bar pro Minute. Nach 100 Minuten betrug der Preßdruck 1,2 bar, der solange beibehalten wurde, bis kein Wasser mehr austrat.One minute after the solidification of the molding compound - determined by finger pressure - the compressed air line was connected to the pipe socket. The initial pressure was 0.2 bar, the pressure increase 0.01 bar per minute. After 100 minutes the pressure was 1.2 bar, which was maintained until no more water emerged.
Bei Anlegung des Preßdrucks trennte sich das Original von der Formmasse. Der Formkasten mit dem Negativmodell wurde gleichmäßig nach oben abgehoben und hochkant gestellt, damit das ausgepreßte Wasser frei abfließen konnte.When the pressure was applied, the original separated from the molding compound. The mold box with the negative model was lifted evenly upwards and placed upright so that the squeezed water could flow away freely.
Die Resttrocknung des Formkastens mit Negativmodell erfolgt über Nacht bei 60 - 80°C.The residual drying of the molding box with negative model takes place overnight at 60 - 80 ° C.
Nach Trocknung wurde der Formkasten mit dem Negativmodell für den folgenden Aluminiumguß an eine Vakuumleitung ange-- schlossen. Es stellte sich ein Unterdruck von -0,9 bar ein. Die geschmolzene Aluminiumlegierung (720°C) wurde in die evakuierte Form eingefüllt. Die Entformung des Gußteiles erfolgte nach völliger Erstarrung der Legierung, was nach ca. 20 Minuten der Fall war. Die Negativform konnte für drei weitere Metallgüsse eingesetzt werden.After drying, the mold box with the negative model for the following cast aluminum was connected to a vacuum line. A negative pressure of -0.9 bar was established. The molten aluminum alloy (720 ° C) was filled into the evacuated mold. The casting was demolded after the alloy had completely solidified, which was the case after about 20 minutes. The negative mold could be used for three more metal castings.
Anstelle des im Beispiel 1 eingelegten porösen Schlauches wurde eine gelochte Mineralwollfasermatte mit 2 cm Dicke verwendet. Der Lochdurchmesser betrug 1,5 cm, der Abstand von Lochung zu Lochung 2 - 3 cm. Um ein Hochschwimmen der Mineralwollfasermatte zu unterbinden, wurde sie kurzzeitig in Wasser getaucht. Vor dem Einbringen der Drainage wurde der Formkasten mit der Gießmasse ca. 1 cm über das Original gefüllt und anschlieBend die Mineralwollfasermatte mit einem Abstand von ca. 1 cm über der Originaloberfläche fixiert und danach der Formkasten aufgefüllt. Ausbrechen, Evakuieren und Metallgießen erfolgten wie im Beispiel 1.Instead of the porous tube inserted in Example 1, a perforated mineral wool fiber mat with a thickness of 2 cm was used. The hole diameter was 1.5 cm, the distance from hole to hole was 2-3 cm. In order to prevent the mineral wool fiber mat from floating up, it was briefly immersed in water. Before the drainage was introduced, the molding box was filled with the casting compound approx. 1 cm above the original and then the mineral wool fiber mat was fixed at a distance of approx. 1 cm above the original surface and the molding box was then filled up. Breaking out, evacuation and metal casting were carried out as in Example 1.
In der beiliegenden Figur, die einen Querschnitt durch die beim erfindungsgemäßen Verfahren eingesetzte Gußform zeigt, dient zur weiteren Erläuterung des Erfindungsgegenstandes.In the accompanying figure, which shows a cross section through the casting mold used in the method according to the invention, serves to further explain the subject matter of the invention.
Mit 1a) und 1b) sind in der Figur Teile des Formkastens bezeichne Das in der Kastenhälfte 1a) liegende Modell 7 ist mit dem Maschendrahtgewebe 6, auf dem der poröse Gewebeschlauch 2 schlangenförmig angeordnet ist, umgeben. Das Druckgas wird über die Stutzen bei 4 eingeleitet und das Vakuum über den gleichen Stutzen abgezogen. Die Formmasse ist mit der Ziffer 3 angedeutet.
Claims (11)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT84104215T ATE64114T1 (en) | 1983-05-06 | 1984-04-13 | PROCESS FOR THE MANUFACTURE OF PRECISION CASTINGS ACCORDING TO THE PLASTER MOLDING PROCESS. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3316571 | 1983-05-06 | ||
| DE3316571A DE3316571C2 (en) | 1983-05-06 | 1983-05-06 | Process for the production of precision casting molds according to the plaster of paris - molding process, casting mold and their use |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0124801A2 true EP0124801A2 (en) | 1984-11-14 |
| EP0124801A3 EP0124801A3 (en) | 1988-03-23 |
| EP0124801B1 EP0124801B1 (en) | 1991-06-05 |
Family
ID=6198315
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP84104215A Expired - Lifetime EP0124801B1 (en) | 1983-05-06 | 1984-04-13 | Method of making precision castings by using the plaster moulding process |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4541471A (en) |
| EP (1) | EP0124801B1 (en) |
| AT (1) | ATE64114T1 (en) |
| DE (2) | DE3316571C2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0203333A2 (en) * | 1985-05-30 | 1986-12-03 | Giulini Chemie GmbH | Method of producing moulds, patterns and tools on base of hard gypsum and/or cement |
| DE3832370A1 (en) * | 1988-04-29 | 1989-11-09 | Giulini Chemie | NEW CERAMIC MIXTURES SUITABLE FOR PRODUCING WATER-WASHABLE CORES AND SHAPES |
| EP0467025A2 (en) * | 1990-07-20 | 1992-01-22 | Giulini Chemie GmbH | Light moulds, patterns and tools on gypsum base |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3320309C2 (en) * | 1983-06-04 | 1985-08-14 | Giulini Chemie Gmbh, 6700 Ludwigshafen | Process for the production of precision measuring molds, casting molds and their use |
| GB2408260A (en) * | 2003-11-20 | 2005-05-25 | Doncasters Ltd | Moulding composition including water-insoluble lubricant |
| JP2007522967A (en) * | 2004-02-19 | 2007-08-16 | ジェ サム リ | Ceramic mold, molding apparatus and manufacturing method |
| JPWO2006006527A1 (en) * | 2004-07-12 | 2008-04-24 | 大日本印刷株式会社 | Electromagnetic shield filter |
| CN109226704B (en) * | 2018-11-03 | 2024-06-14 | 深圳阿尔泰克轻合金技术有限公司 | Aluminum ingot production system and method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE564615A (en) * | ||||
| US2529835A (en) * | 1947-01-18 | 1950-11-14 | United States Gypsum Co | Metal-casting molds and processes and materials for producing the same |
| US2882569A (en) * | 1957-03-29 | 1959-04-21 | Ram Inc | Method and apparatus for molding and hardening articles |
| US3651855A (en) * | 1968-02-23 | 1972-03-28 | Henri Jean Daussan | Continuous slurry supply method for fabrication of mold linings |
| US3825058A (en) * | 1972-04-15 | 1974-07-23 | Sintokogio Ltd | Mold prepared by vacuum sealed molding process |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1939433B2 (en) * | 1969-08-02 | 1970-10-08 | Daimler Benz Ag | Metering catalyst into phenolic resin mould - ing material |
| DE1940924A1 (en) * | 1969-08-12 | 1971-02-25 | Michel Horst Werner | Age-hardening sand moulds of cores |
| CH524415A (en) * | 1970-04-20 | 1972-06-30 | Gruenzweig & Hartmann | Equipment for the implementation of the full mold casting process |
| JPS544817A (en) * | 1977-06-15 | 1979-01-13 | Hitachi Ltd | Selffhardening casting sand |
-
1983
- 1983-05-06 DE DE3316571A patent/DE3316571C2/en not_active Expired
-
1984
- 1984-04-13 DE DE8484104215T patent/DE3484663D1/en not_active Expired - Lifetime
- 1984-04-13 AT AT84104215T patent/ATE64114T1/en not_active IP Right Cessation
- 1984-04-13 EP EP84104215A patent/EP0124801B1/en not_active Expired - Lifetime
- 1984-05-07 US US06/608,046 patent/US4541471A/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE564615A (en) * | ||||
| US2529835A (en) * | 1947-01-18 | 1950-11-14 | United States Gypsum Co | Metal-casting molds and processes and materials for producing the same |
| US2882569A (en) * | 1957-03-29 | 1959-04-21 | Ram Inc | Method and apparatus for molding and hardening articles |
| US3651855A (en) * | 1968-02-23 | 1972-03-28 | Henri Jean Daussan | Continuous slurry supply method for fabrication of mold linings |
| US3825058A (en) * | 1972-04-15 | 1974-07-23 | Sintokogio Ltd | Mold prepared by vacuum sealed molding process |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0203333A2 (en) * | 1985-05-30 | 1986-12-03 | Giulini Chemie GmbH | Method of producing moulds, patterns and tools on base of hard gypsum and/or cement |
| DE3519367A1 (en) * | 1985-05-30 | 1986-12-04 | Giulini Chemie Gmbh, 6700 Ludwigshafen | METHOD FOR THE PRODUCTION OF MOLDS, MODELS AND TOOLS ON HARD PLASTER AND / OR CEMENT BASE |
| EP0203333A3 (en) * | 1985-05-30 | 1987-07-22 | Giulini Chemie Gmbh | Method of producing moulds, patterns and tools on base of hard gypsum and/or cement |
| US4749431A (en) * | 1985-05-30 | 1988-06-07 | Giulini Chemie Gmbh | Process for producing molds, models and tools based on hard gypsum and/or cement |
| DE3832370A1 (en) * | 1988-04-29 | 1989-11-09 | Giulini Chemie | NEW CERAMIC MIXTURES SUITABLE FOR PRODUCING WATER-WASHABLE CORES AND SHAPES |
| EP0467025A2 (en) * | 1990-07-20 | 1992-01-22 | Giulini Chemie GmbH | Light moulds, patterns and tools on gypsum base |
| EP0467025A3 (en) * | 1990-07-20 | 1992-12-09 | Giulini Chemie Gmbh | Light moulds, patterns and tools on gypsum base |
Also Published As
| Publication number | Publication date |
|---|---|
| US4541471A (en) | 1985-09-17 |
| EP0124801A3 (en) | 1988-03-23 |
| DE3316571C2 (en) | 1985-08-22 |
| ATE64114T1 (en) | 1991-06-15 |
| DE3484663D1 (en) | 1991-07-11 |
| DE3316571A1 (en) | 1984-11-08 |
| EP0124801B1 (en) | 1991-06-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0124801B1 (en) | Method of making precision castings by using the plaster moulding process | |
| DE2626224C2 (en) | Process for removing molding compound from a mold filled with casting | |
| DE2352492B2 (en) | METHOD FOR MANUFACTURING VACUUM-STABILIZED CASTING FORMS | |
| DE2263212C2 (en) | Process for producing leather-hard moldings | |
| DE3320309C2 (en) | Process for the production of precision measuring molds, casting molds and their use | |
| EP0125510B1 (en) | Method of making precision castings | |
| CH622726A5 (en) | Method for knocking out silicate-bound moulding compound from a mould filled with casting | |
| DE2611293A1 (en) | METHOD OF MANUFACTURING REINFORCED SPRAYED CONCRETE PIPES | |
| DE874724C (en) | Process for the production of ceramic molded bodies, in particular larger ones, e.g. B. sanitary items, such as wash basins, sinks or the like. | |
| DE1584396A1 (en) | Process for the dimensionally accurate production of molded parts from fiber cement | |
| AT93334B (en) | Ceramic shape. | |
| DE703145C (en) | Method and device for the production of fused pores, in particular fused glass pods | |
| AT58635B (en) | Process for the production of concrete pipes and the like. | |
| AT204196B (en) | Method and device for the production of casting molds for the aluminothermic inter-cast welding of workpieces, preferably rails | |
| DE470233C (en) | Process for the production of non-metallic closed frames for boxless casting | |
| DE663057C (en) | Process for the production of molded bodies with lime or cement binding | |
| DE808451C (en) | Inside rattle | |
| DE902432C (en) | Process for the production of molding and core compounds for foundry purposes | |
| DE583544C (en) | Process for the mass production of rod-shaped bodies | |
| AT54656B (en) | Process for the production of artificial marble. | |
| DE1783159C3 (en) | Method of sealing joints. Eliminated from: 1758487 | |
| AT129774B (en) | Method and device for the mass production of rod-shaped bodies. | |
| EP0043912B1 (en) | Vacuum casting process | |
| DE883494C (en) | Process for the production of a washable mold core for the production of compression molded items | |
| DE521653C (en) | Process for the production of cores for hollow blocks to be cast |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Designated state(s): AT BE CH DE FR GB IT LI LU NL SE |
|
| 17P | Request for examination filed |
Effective date: 19841201 |
|
| PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
| AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT BE CH DE FR GB IT LI LU NL SE |
|
| 17Q | First examination report despatched |
Effective date: 19890316 |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE CH DE FR GB IT LI LU NL SE |
|
| REF | Corresponds to: |
Ref document number: 64114 Country of ref document: AT Date of ref document: 19910615 Kind code of ref document: T |
|
| REF | Corresponds to: |
Ref document number: 3484663 Country of ref document: DE Date of ref document: 19910711 |
|
| ITF | It: translation for a ep patent filed | ||
| GBT | Gb: translation of ep patent filed (gb section 77(6)(a)/1977) | ||
| ET | Fr: translation filed | ||
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| 26N | No opposition filed | ||
| EPTA | Lu: last paid annual fee | ||
| EAL | Se: european patent in force in sweden |
Ref document number: 84104215.3 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: LU Payment date: 19950301 Year of fee payment: 12 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19950407 Year of fee payment: 12 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19950412 Year of fee payment: 12 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 19950413 Year of fee payment: 12 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19950430 Year of fee payment: 12 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19950728 Year of fee payment: 12 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19960413 Ref country code: GB Effective date: 19960413 Ref country code: AT Effective date: 19960413 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Effective date: 19960430 Ref country code: CH Effective date: 19960430 Ref country code: BE Effective date: 19960430 |
|
| BERE | Be: lapsed |
Owner name: GIULINI CHEMIE G.M.B.H. Effective date: 19960430 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19961101 |
|
| GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19960413 |
|
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
| NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee |
Effective date: 19961101 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 20000417 Year of fee payment: 17 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20010305 Year of fee payment: 18 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20010414 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20010420 Year of fee payment: 18 |
|
| EUG | Se: european patent has lapsed |
Ref document number: 84104215.3 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20021101 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20021231 |
|
| REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |