Method for controlling foam production in reduced pressure fining

• US 7,134,300 B2
• Filed: 01/04/2005
• Issued: 11/14/2006
• Est. Priority Date: 07/18/2001
• Status: Expired due to Fees

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Hayes, James C., Palmquist, Ronald W., Woolley, Frank, Murnane, Rand A.
• Primary Examiner(s): HUG, JOHN ERIC
• Application Number:
  US11/029,802
• Publication Number:
  US 20050155387A1
• Time in Patent Office: 679 Days
• Field of Search: 65178-180, 65/291.7, 65/34, 65/994, 651/25, 651/341, 651/342, 651/344, 651/346, 651/347, 651/348, 651/349, 651/351, 651/352, 651/353, 651/354, 651/356, 651/57, 653/46, 653/47, 961/55, 962/02, 962/03, 96176-180, 226207-212, 226233-235, 75/106.4, 373/27, 373 33- 35, 266233-235, 266207-212
• US Class Current: 65/346
• CPC Class Codes: C03B 5/20 Bridges, shoes, throats, or other devices for withholding dirt, foam, or batch
• CPC Class Codes: C03B 5/202 Devices for blowing onto the melt surface, e.g. high momentum burners
• CPC Class Codes: C03B 5/205 Mechanical means for skimming or scraping the melt surface
• CPC Class Codes: C03B 5/2252 under reduced pressure, e.g. with vacuum refiners
• CPC Class Codes: C03B 5/262 Drains, i.e. means to dump glass melt or remove unwanted materials

Abstract

A method for controlling the foam produced when a molten material encounters reduced pressure in a vacuum chamber includes passing the molten material through an aging zone in the vacuum chamber in which the molten material is allowed to drain from between the bubbles of the foam and then collapsing the bubbles of the drained foam.

Claims

1. A reduced pressure finer, comprising:

a finer chamber having a pressure below atmospheric pressure;

a first conduit for conducting molten material to the finer chamber, the first conduit being inclined to the vertical, wherein bubbles in the molten material collect at a surface of the first conduit as the molten material flows through the first conduit;

a standpipe hydraulically connected to the first conduit and through which the bubbles collected on the surface of the first conduit are removed; and

a second conduit for removing the molten material from the finer chamber.

2. The reduced pressure finer of claim 1, wherein the standpipe is positioned such that the level of molten material in the standpipe is above the level of molten material in the finer chamber.

3. The reduced pressure finer of claim 1, wherein the standpipe is positioned such that the level of molten material in the standpipe is below the level of molten material in the finer chamber.