Stirrers for minimizing erosion of refractory metal vessels in a glass making system

• US 8,485,717 B2
• Filed: 07/24/2012
• Issued: 07/16/2013
• Est. Priority Date: 12/21/2006
• Status: Expired due to Fees

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Adelsberg, Lee Martin, Goller, Martin Herbert, Lineman, David Myron, Murphy, James Patrick
• Primary Examiner(s): Cooley, Charles E
• Application Number:
  US13/556,714
• Publication Number:
  US 20130003492A1
• Time in Patent Office: 357 Days
• Field of Search: 65178-180, 366/325.1, 3663281-3284, 366/279, 366342-343, 366262-265, 366/270
• US Class Current: 366/328.2
• CPC Class Codes: B01F 27/0531 with particular surface characteristics, e.g. coated or rough
• CPC Class Codes: B01F 27/1123 sickle-shaped, i.e. curved in at least one direction
• CPC Class Codes: B01F 27/1152 with separate elements other than discs fixed on the discs, e.g. vanes fixed on the discs
• CPC Class Codes: B01F 27/50 Pipe mixers, i.e. mixers wherein the materials to be mixed flow continuously through pipes, e.g. column mixers
• CPC Class Codes: B01F 27/80 with stirrers rotating about a substantially vertical axis
• CPC Class Codes: C03B 5/1675 Platinum group metals
• CPC Class Codes: C03B 5/187 with moving elements

Abstract

Stirring apparatuses for stirring molten glass are disclosed. The method includes stirring a molten glass with a stirrer comprising a layer containing at least about 50% iridium. An apparatus comprising an iridium-containing layer is also presented. In one embodiment, an apparatus for stirring molten glass includes a cylinder comprising a bore. A stirrer may be disposed in the bore. The stirrer may include a platinum or platinum alloy shaft coaxial with the cylinder. A plurality of impellers may project radially from the shaft into close proximity of a wall of the cylinder. Each impeller may include an arcuate distal end portion farthest from the shaft. The distal end portion of each impeller consists of iridium or an iridium alloy and the remainder of the impeller consists of platinum or a platinum alloy. The stirring apparatuses reduce metal loss from the refractory metal of the stirring apparatus.

Claims

1. A stifling apparatus for stirring molten glass comprising a cylindrical vessel;

a stirrer rotatably disposed within the cylindrical vessel, the stirrer comprising;

a shaft;

an impeller blade coupled to the shaft and extending outward therefrom, the impeller blade comprising a cylindrical member parallel to an axis of rotation of the shaft; and

wherein a distal end portion of the cylindrical member adjacent an inner surface of the cylindrical vessel defines a plurality of holes extending through the distal end portion, the plurality of holes being limited to a region of the distal end portion less than 5 cm in either circumferential direction from a point in the distal end portion farthest from the stirrer shaft.

2. The stifling apparatus according to claim 1, wherein a diameter of the plurality of holes is less than 1 cm each.

3. The stifling apparatus according to claim 1, further comprising a web member coupled to and perpendicular to the shaft, the web member being further coupled to the cylindrical member.

4. The stifling apparatus according to claim 1, wherein the distal end portion comprises iridium.

5. The stifling apparatus according to claim 4, wherein the distal end portion consists of iridium.

6. The stirring apparatus according to claim 1, wherein a wall of the cylindrical vessel comprises iridium.