DE1019804B - Process for the manufacture of optical glass free of dynamic effects - Google Patents
Process for the manufacture of optical glass free of dynamic effectsInfo
- Publication number
- DE1019804B DE1019804B DEJ5956A DEJ0005956A DE1019804B DE 1019804 B DE1019804 B DE 1019804B DE J5956 A DEJ5956 A DE J5956A DE J0005956 A DEJ0005956 A DE J0005956A DE 1019804 B DE1019804 B DE 1019804B
- Authority
- DE
- Germany
- Prior art keywords
- optical glass
- current
- manufacture
- melt
- dynamic effects
- 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/167—Means for preventing damage to equipment, e.g. by molten glass, hot gases, batches
- C03B5/1677—Means for preventing damage to equipment, e.g. by molten glass, hot gases, batches by use of electrochemically protection means, e.g. passivation of electrodes
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/02—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating
- C03B5/027—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture in electric furnaces, e.g. by dielectric heating by passing an electric current between electrodes immersed in the glass bath, i.e. by direct resistance heating
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Glass Melting And Manufacturing (AREA)
Description
Verfahren zur Herstellung tyndalleffektfreien optischen Glases Die Erfindung bezieht sich auf ein Verfahren zur Herstellung tyndalleffektfreien optischen Glases mittels Joulescher Wärme.Process for producing tyndall-effect-free optical glass Die The invention relates to a method for producing optical tyndall effect-free Glass by means of Joule heat.
Beim elektrischen Schmelzen von Glas durch Joulesche Wärme wird der Heizstrom dem Schmelzgut in der Regel mit Hilfe von Elektroden zugeführt, die in das Schmelzgut eintauchen. oder auf sonstige Weise einen guten Stromübergang sichern. Infolge der hierbei normalerweise auftretenden elektrolytischen Zersetzung der Schmelze, die meist ein Verfärben des Glases verursacht, ist es im allgemeinen nicht möglich, ein reines und ungefärbtes Glas zu erschmelzen, wenn man einen Heizstrom mit der üblichen Netzfrequenz von 50 Hz verwendet.When glass is electrically melted by Joule heat, the Heating current is usually supplied to the molten material with the help of electrodes that are in immerse the melted material. or secure a good current transfer in some other way. As a result of the electrolytic decomposition of the melt that normally occurs here, which usually causes discoloration of the glass, it is generally not possible to melt a pure and uncoloured glass, if you have a heating current with the usual mains frequency of 50 Hz.
Man hat deshalb schon vorgeschlagen, die Frequenz des Heizstromes auf 500 bis 1000 Hz, gegebenenfalls noch höher, zu steigern, und hierbei ein ungefärbtes Glas erzielt, d. h., die elektrolytische Zersetzung der Schmelze hat sich also bei diesen Frequenzen vermeiden lassen.It has therefore already been proposed to increase the frequency of the heating current to 500 to 1000 Hz, possibly even higher, and this is an uncolored one Glass achieved, d. That is, the electrolytic decomposition of the melt has increased avoid these frequencies.
Dagegen tritt ein anderer Effekt auf, der bisher durch die Verfärbung der Schmelze infolge elektrolytischer Zersetzung überdeckt war, nämlich die Zerstäubung der Elektroden. Diese Zerstäubung ist bei 1000 Hz so fein, daß siie sich der Wahrnehmung mit dem unbewaffneten Auge entzieht, sich jedoch bei scharfer seitlicher Dunkelfeldbeleuchtung als starke Streuung (Tyndalleffekt) bemerkbar macht, so daß das betreffende- Glas für optische Zwecke unbrauchbar wird. Diese Erscheinung tritt besonders deutlich gerade dann auf, wenn chemisch unangreifbare Elektroden, wie aus Platinmetallen, verwendet werden, da das zerstäubte Metall hier nicht von der Schmelze im Laufe der Zeit gelöst werden kann, wie bei Elektroden aus unedlen Metallen.On the other hand, there is another effect, which was previously caused by the discoloration the melt was covered as a result of electrolytic decomposition, namely the atomization of the electrodes. At 1000 Hz, this atomization is so fine that it can be perceived evades with the naked eye, but with sharp dark field illumination from the side as a strong scattering (Tyndall effect) makes noticeable, so that the glass in question becomes unusable for optical purposes. This phenomenon is particularly evident especially when chemically unassailable electrodes, such as those made of platinum metals, be used because the atomized metal is not here from the melt in the course can be resolved over time, as in the case of electrodes made of base metal.
Andererseits hat sich aber in der letzten Zeit erwiesen, daß es beim Erschmelzen zahlreicher Glassorten äußerst wichtig ist, daß die Schmelze mit keinen anderen Materialien als mit Platin oder Legierungen mit hohem Plantingehalt in Berührung kommt.On the other hand, it has recently been shown that the Melting numerous types of glass is extremely important that the melt with none in contact with materials other than platinum or alloys with a high plantin content comes.
Es wurde nun gefunden, daß man auch unter dieser Bedingung optisch einwandfreies, tyndalleffektfreies optisches Glas erschmelzen kann, wenn nach der Erfindung unter Anwendung von Elektroden aus Platin-oder hochplatinhaltigen Legierungen ein Strom mit einer Frequenz von wenigstens 4000 Hz durch die Schmelze geleitet wird.It has now been found that even under this condition one can optically flawless, tyndall effect-free optical glass can melt if after the Invention using electrodes made of platinum or high-platinum alloys a current with a frequency of at least 4000 Hz is passed through the melt will.
Mit Rücksicht auf die hohen Kosten der genannten Metalle ist es zweckmäßig, die Oberfläche der Elektroden klein zu halten, d. h. die übergangsstromdichte zwischen den Elektroden und dem Schmelzgut zu erhöhen.In view of the high costs of the metals mentioned, it is advisable to to keep the surface of the electrodes small, d. H. the transition current density between to increase the electrodes and the melting material.
Hierdurch nimmt die übergangsstromdichte zwischen den Elektroden und dem Schmelzgut beträchtliche Werte an. Falls diese auf 10 A/qcm oder mehr gesteigert wird, erhöht man zweckmäßig die Frequenz des Heizstromes auf mindestens 7000 Hz. Auf diese Weise erhält man trotz der hohen Stromdichte noch einwandfreies optisches Glas.This increases the transition current density between the electrodes and the melt material has considerable values. If this is increased to 10 A / qcm or more it is advisable to increase the frequency of the heating current to at least 7000 Hz. In this way, despite the high current density, the optical quality is still perfect Glass.
Um die Kosten der Platinelektroden klein zu halten, empfiehlt es sich, sie aus dünnen Metallblechen herzustellen.In order to keep the costs of the platinum electrodes low, it is advisable to make them from thin metal sheets.
Beim Schmelzen von Gläsern in einem Platintiegel kann man mit einer einzigen, vorzugsweise rohrförmigen Elektrode auskommen und dabei den Tiegel als Gegenelektrode verwenden.When melting glasses in a platinum crucible, you can use a get along single, preferably tubular electrode and thereby use the crucible as Use counter electrode.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEJ5956A DE1019804B (en) | 1952-06-06 | 1952-06-06 | Process for the manufacture of optical glass free of dynamic effects |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEJ5956A DE1019804B (en) | 1952-06-06 | 1952-06-06 | Process for the manufacture of optical glass free of dynamic effects |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE1019804B true DE1019804B (en) | 1957-11-21 |
Family
ID=7198433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DEJ5956A Pending DE1019804B (en) | 1952-06-06 | 1952-06-06 | Process for the manufacture of optical glass free of dynamic effects |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE1019804B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE720950C (en) * | 1936-11-30 | 1942-05-20 | Algemeene Kunstvezel Mij N V | Process and furnace for melting and luting glass and other refractory materials by means of an electric current |
| FR921929A (en) * | 1943-02-02 | 1947-05-22 | Movable electrode device for electric melting furnaces, in particular for glass melting furnaces | |
| CH251610A (en) * | 1944-01-27 | 1947-11-15 | Egyesuelt Izzolampa | Process for electrically melting glass. |
| FR936821A (en) * | 1944-01-27 | 1948-07-30 | Egyesu Lt Izzolampa Es Villamo | Process for the electric melting of glass |
-
1952
- 1952-06-06 DE DEJ5956A patent/DE1019804B/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE720950C (en) * | 1936-11-30 | 1942-05-20 | Algemeene Kunstvezel Mij N V | Process and furnace for melting and luting glass and other refractory materials by means of an electric current |
| FR921929A (en) * | 1943-02-02 | 1947-05-22 | Movable electrode device for electric melting furnaces, in particular for glass melting furnaces | |
| CH251610A (en) * | 1944-01-27 | 1947-11-15 | Egyesuelt Izzolampa | Process for electrically melting glass. |
| FR936821A (en) * | 1944-01-27 | 1948-07-30 | Egyesu Lt Izzolampa Es Villamo | Process for the electric melting of glass |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE2559895C2 (en) | Method and device for pulling optical fibers for the transmission of messages | |
| DE1421842B2 (en) | SOLIDIFIED GLASS OBJECT MADE FROM AN ALKALINE ALUMINUM SILICATE GLASS AND METHOD FOR ITS MANUFACTURING | |
| DE1421846B2 (en) | FASTENED GLASS OBJECT WITH AN INTERIOR OF THE GLASS SURROUNDING THE COMPRESSIVE STRESS LAYER ON THE SURFACE OF THE GLASS AND THE PROCESS FOR ITS MANUFACTURING | |
| DE3874615T2 (en) | OPTICAL OBJECT WITH BREAKING INDEX AND METHOD FOR THE PRODUCTION THEREOF. | |
| DE1471918B2 (en) | Method and device for the production of glass threads | |
| DE2106018A1 (en) | Glass with improved thermal temperability and process for its manufacture | |
| DE102019217977A1 (en) | Glass, a method for making a glass and a glass melting plant | |
| DE804605C (en) | Use of an alloy for apparatus parts that come into contact with molten glass | |
| DE1596395A1 (en) | Method and device for the production of so-called optical fibers | |
| DE1019804B (en) | Process for the manufacture of optical glass free of dynamic effects | |
| DE1910774A1 (en) | Process for increasing the mechanical strength of glass, in particular glass panes | |
| DE2625313A1 (en) | EYEGLASSES WITH HIGH MECHANICAL STRENGTH | |
| DE1955175B2 (en) | Method and apparatus for producing glass and crystalline material | |
| DE1957626C3 (en) | Process for producing an optical waveguide gradient glass fiber by ion exchange and apparatus for carrying out this process | |
| DE839387C (en) | Sockets for electric lamps and manufacturing processes for them | |
| DE102004015055A1 (en) | Method and arrangement for feeding a molten glass to a processing process | |
| DE1901053B1 (en) | Optical fiber and its method of manufacture | |
| DE653769C (en) | Method and device for hardening glass | |
| CH313940A (en) | Process for electrically melting glass | |
| EP0804389B1 (en) | Optical glass with varying refractive index | |
| DE712699C (en) | Process for the continuous production of flashed glass | |
| DE1191980B (en) | Refractive optical element | |
| DE2039239C (en) | Light-guiding glass element with a zone made of high refractive glass, an adjacent lower refractive glass zone and a transition area created by ion diffusion with a continuous refractive index gradient and a process for its manufacture | |
| DE1421842C (en) | Solidified glass object made from an alkali aluminum Sihkat glass and process for its manufacture | |
| DE1913136B2 (en) | PROCESS FOR INCREASING THE MECHANICAL STRENGTH OF ALKALINE-CONTAINING GLASS OF THIN DIMENSIONS BY EXCHANGING IONS |