Methods for the batchwise production of glass

• US 4,820,329 A
• Filed: 12/01/1986
• Issued: 04/11/1989
• Est. Priority Date: 05/17/1984
• Status: Expired due to Fees

• Current Assignee: SCHOTT GLASWERKE, HATTENBERGSTRASSE 10, 6500 MAINZ, GERMANY
• Original Assignee: Schott Glaswerke
• Inventors: Gunthner, Franz
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US06/936,938
• Time in Patent Office: 862 Days
• Field of Search: 65/32, 65/71, 65/134, 65/135, 65/178, 65/324-325, 65/333, 65/335, 65/340-342, 65/347
• US Class Current: 65/134.4
• CPC Class Codes: C03B 5/00 Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
• CPC Class Codes: C03B 5/0275 Shaft furnaces C03B5/0277 takes precedence
• CPC Class Codes: C03B 5/0277 Rotary furnaces
• CPC Class Codes: C03B 5/193 using gas, e.g. bubblers
• CPC Class Codes: C03B 5/225 Refining C03B5/18 takes precedence ; Refining agents C03C1/004
• CPC Class Codes: C03B 5/2252 under reduced pressure, e.g. with vacuum refiners
• CPC Class Codes: C03B 5/2255 by centrifuging
• CPC Class Codes: C03B 5/23 Cooling the molten glass C03B5/18, C03B5/225 take precedence
• CPC Class Codes: C03B 5/26 Outlets , e.g. drains, siphons; Overflows , e.g. for supplying the float tank, tweels
• CPC Class Codes: C03B 5/28 Siphons
• CPC Class Codes: C03B 7/06 Means for thermal conditioning or controlling the temperature of the glass
• CPC Class Codes: C03B 7/14 Transferring molten glass or gobs to glass blowing or pressing machines C03B7/18 - C03B7/22 take precedence
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates

Abstract

A process for the batchwise production of glass performs melting, refining and discharging steps in electrically heated identical vessels, wherein at least the refining step is conducted during rotation of a vessel, and discharging of the refined glass takes place while the vessel is at rest. By using several vessels, which are either mobile or which are connected with one another by movable spouts, feeding of molten glass to a distributing channel for further processing is done continuously. Vessels according to the invention have electrodes for heating purposes; outlet port sealing arrangements; and ports for applying over-pressure or a vacuum to control glass exit speed. Blast pipes may be disposed in proximity with outlet ports in order to improve flow of the glass melt by introducing blasts of an inert gas.

Claims

1. A process for the production of molten glass for subsequent processing from batches of solid glass pieces by a series of melting, refining and discharging operations, comprising the steps of:

providing a plurality of similar vessels for retaining the glass, each vessel having heating electrodes positioned adjacent the bottom thereof and closable opening in the bottom thereof for discharging the glass into a distribution system;

performing all of said operations in a single vessel for each batch of glass;

for each batch of glass, melting a mass of solid glass pieces comprising the glass for one batch by covering the electrodes of the vessel with the mass of solid glass pieces and heating the mass of solid glass pieces to produce a mass of molten glass;

retaining the entire mass of molten glass for the one batch in a single vessel, and while keeping the electrodes completely immersed in the mass of molten glass in the single vessel, performing the refining step by rotating the vessel at a speed sufficient to produce a parabolic surface on the mass of molten glass through which parabolic surface occluded gas bubbles escape as the glass is refined;

stopping rotation of the vessel after sufficient refining, and

discharging the entire batch of refined glass after stopping the vessel.

2. The process of claim 1, further including the steps of:

feeding the batch of refined glass via the distribution system to further processing stations after discharging the batch of refined glass from the vessel; and

storing at least a portion discharged molten glass in an equalizing chamber connected to the distribution system to maintain the amount of glass in the distribution system at a sufficient level during the period of time between discharging different vessels.

3. The process of claim 2, including the step of connecting vessels and the refining vessels are with one another by movable troughs.

4. The process of claim 2, wherein the discharging step is performed by discharging refined glass into at least one spout connected to a distribution system.

5. The process of claim 4, wherein each vessel has a spout integral therewith.

6. The process of claim 4, characterized in that the vessels are fixed and the spout is movable with respect to the vessels.

7. The process of claim 4, wherein vessels are movable and the spout is fixed with respect to the vessels.

8. The process of claim 4, further including the step of cooling the melt while the melt is in the distributing system.

9. The process of claim 1, further including the step of controlling efflux velocity of the glass during discharge of the glass from the vessels.

10. The process of claim 9, wherein the efflux velocity of the glass is controlled by the application of pressure.

11. The process of claim 1, further including the step of blowing an inert gas into the glass melt during fusing thereof.

12. The process of claim 1, wherein the glass melt is discharged through an outlet port which is sealed mechanically.

13. The process of claim 12, wherein the mechanized seal is effected by freezing the glass melt.