KR102509016B1 - Apparatus and method for conditioning molten glass - Google Patents

Abstract

An apparatus for bubbling gas into molten glass is disclosed. The bubbler will include a sleeve, a nozzle secured to one end of the sleeve, and a capillary member slidably positioned within the sleeve below the nozzle. The capillary member is connected to a positioning assembly configured to move the capillary member within the sleeve.

Description

Apparatus and method for conditioning molten glass

This application claims priority to U.S. Provisional Application No. 62/129,210, filed March 6, 2015 under 35 U.S.C.§119, the contents of which are incorporated herein by reference in their entirety.

The present disclosure relates to apparatus for conditioning molten glass, and more particularly to apparatus for injecting (eg, bubbling) a gas into the molten glass.

Commercial-scale glass production is typically carried out in a refractory ceramic melting vessel where raw materials (batch) are added to a melting vessel and the batch is heated to a temperature that undergoes a chemical reaction to produce molten glass. Several methods of heating the batch can be used including gas fired burners, electric current or both.

Conditioning of the molten glass, such as refining or homogenization, can be performed in some part of the melting vessel structure or in another vessel located downstream of the melting vessel and connected to the melting vessel by conduits. In certain processes, bubbling gas into the melting vessel may be used to promote and enhance homogenization of the molten glass or to bring about a redox state of a batch component, such as a fining agent.

Existing bubblers often use a ceramic tube with at least one side directly exposed to the corrosive environment of the high temperature provided by the molten glass. Thus, they exhibited significant corrosion of the ceramic tubes starting at such exposed surfaces. For hard glass commonly used in the manufacture of optical products such as glass for display substrates, the typical temperature range of the molten glass in the melting vessel is from about 1500°C to about 1550°C. The molten glass temperature in the fining vessel can be quite high, reaching 1700°C. Also, the molten glass may freeze or condense, blocking the exit of the passage and stopping bubble formation, or creating an insoluble crystalline phase. Additionally, defects and/or obstructions may occur within the bubbler passage. Moreover, the gas supplied to create the bubbles can potentially leak at the bottom of the bubbler support between the platinum cladding and the support, reducing gas pressure and reducing process stability. If these detrimental effects occur, the bubbler must be replaced.

Bubblers are a practical and inexpensive solution for improving glass quality and potentially glass refining. However, because of the above mentioned problems in high temperature operation, modifications are needed to address the current shortcoming.

Bubblers for injecting bubbles of gas into a vessel containing molten glass in a volume defined by the vessel have long been used, for example, to enhance glass melting. For example, such a bubbling process can increase the natural convection current during the melting process, thereby increasing the homogeneity of the molten glass and glass articles made therefrom. However, molten glass is highly corrosive, and the combination of high temperature and corrosive environment can severely damage conventional bubblers in a relatively short period of time.

Accordingly, in one aspect of the present application, a molten glass conditioning apparatus having a vessel comprising an internal volume is described.

A bubbler extends into the volume of the vessel, the bubbler comprising a sleeve including an internal passageway extending therethrough, an internal passageway secured to a first end of the sleeve and extending between an inlet orifice and an outlet orifice. It has a capillary member including a nozzle, and a plurality of capillary passages extending therethrough. The sleeve and nozzle will contain platinum. The capillary member is slidably engaged within the inner passage of the sleeve. The nozzle includes a recessed portion, and the recessed portion is positioned within the inner passage of the sleeve portion.

The device may further include a cooling device in the cooling section of the device. Additionally, a screw member will be connected to the cooling device. The screw member may also be connected to the sleeve. However, the cooling member does not directly cool the part of the bubbler (sleeve and nozzle) extending into the molten glass.

In exemplary embodiments, the positioning assembly can be rotatably coupled to the screw member, and the capillary member is rotatably rotatable to the positioning assembly to cause the positioning device to move along the screw member upon rotation of the positioning assembly relative to the screw member. It can be connected to the gas supply pipe to which it is connected. a gas supply pipe rotatably connected to the positioning assembly and a capillary member connected to the gas supply pipe, wherein movement of the positioning assembly relative to the screw member causes the capillary member to move within the sleeve, thereby compensating for corrosion of the capillary member; provides

To limit the size of the bubbles produced by the bubbler, the nozzle will include an outer profile that tapers in a direction towards the exit orifice. The inner passage of the nozzle may also include an intermediate chamber having a diameter greater than the diameter of the exit orifice to serve as a location for gas supplied from the plurality of passages of the capillary member to engage.

The nozzle may be secured to the sleeve by a perimeter weld around a joint between the nozzle and the sleeve to prevent gas pressure within the nozzle from separating the nozzle from the sleeve. Additionally or alternatively, the nozzle may also be secured to the sleeve by means of a plurality of plug welds located around the periphery of the sleeve. Preferably, both seam welds and plug welds are used to secure the nozzle to the sleeve.

At least a portion of the sleeve may comprise a ceramic coating, in particular a portion of such a sleeve is located within the cooling device. The ceramic coating helps prevent diffusion welding of the sleeve to the inner wall of the cooling device when prolonged contact between the two occurs. Additionally, at least a portion of the cooling device may include a ceramic coating to prevent corrosion (eg, oxidation) of the cooling device.

The device will further comprise a sealing gasket positioned within the screw member between the capillary member and the screw member. The sealing gasket sits on a sealing lip located in the inner passage of the screw member, and a fitting, for example a screw fitting, presses the sleeve against the sealing gasket via a flange on the sleeve. The sealing gasket includes a passage through which the sleeve extends, and the sealing gasket further seals around the sleeve so that gas, such as atmospheric gas, leaks into the molten glass through the screw member passage and in the gap between the sleeve and the capillary member. or vice versa.

The vessel may be a melting vessel, a fining vessel or a cooling vessel. The vessel may also have one or more connecting conduits.

The output orifice of the nozzle includes an orifice area, which is a cross-sectional area of the orifice in a plane perpendicular to the central axis of the nozzle, and each capillary passage of the plurality of capillary passages includes an output orifice having an orifice area. The sum of the orifice areas of the plurality of capillary passages may be approximately equal to the orifice area of the output orifice of the nozzle. Thus, the volumetric flow rate of gas from such a nozzle exit orifice approximately matches the volumetric flow rate of gas from the capillary member.

In another aspect, a molten glass conditioning apparatus having a vessel including an interior volume and a bubbler extending into the interior volume is disclosed. The bubbler includes a sleeve including an inner passage extending therethrough, a nozzle secured to a first end of the sleeve, and a capillary member including a plurality of passages extending through the capillary member substantially parallel to a central longitudinal axis of the capillary member. to provide The sleeve and nozzle may include platinum. The capillary member is slidably engaged within the inner passage of the sleeve. A screw member is connected to the sleeve, a positioning assembly is rotatably engaged with the screw member, and rotation of the positioning assembly relative to the screw member is configured to move the capillary member within the sleeve.

The device may further include a cooling device connected to the screw member. A gas supply pipe is rotatably connected to the positioning assembly and may further be connected to the capillary member.

The vessel may be a melting vessel, a fining vessel or a cooling vessel. Additionally or alternatively, the vessel may be a cooling conduit.

In another aspect, a method for conditioning molten glass is disclosed comprising flowing molten glass into or out of a vessel, the vessel having a bubbler extending into the molten glass and including an exit orifice. The bubbler includes a sleeve, a nozzle and a capillary member slidably positioned in the sleeve. The method further includes pressurizing the nozzle with a gas supplied through the capillary member, the pressure of the gas being sufficient to prevent the molten glass from entering the nozzle and contacting the capillary member.

The bubble ejection rate from the nozzle may be zero bubbles per minute for a period of at least one hour. The bubble ejection rate from the nozzle may range from 1 to 100 bubbles per minute.

The temperature of the molten glass may range from about 1550 °C to about 1690 °C.

The method further includes, after pressurizing the nozzle, depressurizing the nozzle so that molten glass enters the nozzle, and then pressurizing the nozzle again to extrude the molten glass from the nozzle.

It should be understood that both the above general description and the following detailed description represent embodiments of the present disclosure and are intended to provide an overview or basis for understanding the nature and nature of the described and claimed embodiments. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are included to aid understanding of the embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the present disclosure, and together with the description explain their principles and operation.

1 is a schematic diagram of an exemplary glass manufacturing apparatus according to the present disclosure;
2 is a simplified cross-sectional view of a bubbler according to an embodiment of the present disclosure;
Fig. 3 is a cross-sectional perspective view of a portion of the bubbler of Fig. 2 showing a nozzle secured to the end of the sleeve and a capillary member slidably positioned within the sleeve;
Fig. 4 is a cross-sectional view of the nozzle shown in Fig. 4 in a plane parallel to the central longitudinal axis of the nozzle;
Fig. 5a is a cross-sectional view of the sleeve, nozzle and capillary member of Fig. 4, including a cooling device;
Fig. 5B is an enlarged view of a portion of the Fig. 5A cross-section showing a coating applied to the outer surface of the sleeve;
6 is a perspective view of an example cooling device according to an embodiment of the present disclosure without a sleeve or nozzle installed;
Fig. 7 is a partial perspective view of the cooling device of Fig. 6 with sleeves and nozzles installed;
Fig. 8a is a cross-sectional view of a part (upper part) of a screw member connected to a sleeve and a part of a cooling device, showing a sealing gasket sealed with a capillary member;
Fig. 8b is a cross-sectional view of a portion (lower end) of the screw member of Fig. 8a showing the capillary member connected to the gas supply tube;
Fig. 9 is a perspective view of the sleeve of Fig. 8A showing the flange used to connect the sleeve to the screw member;
10A is a perspective view of a portion (top) of an example positioning assembly connected to the screw member of FIGS. 8A and 8B according to an embodiment of the present disclosure;
Fig. 10b is a perspective view of a portion (bottom) of the positioning assembly of Fig. 10a showing the connection between the gas supply tube and the gas line;
11 is a schematic diagram of another glass manufacturing apparatus according to an embodiment of the present disclosure, the glass manufacturing apparatus comprising a downstream glass manufacturing apparatus including a molten glass conditioning vessel positioned between a melting vessel and a refining vessel, the molten glass the conditioning vessel includes bubblers according to an embodiment of the present disclosure;
12 is a schematic diagram of another glass manufacturing apparatus according to an embodiment of the present disclosure wherein the bubblers disclosed herein are positioned in a fining vessel downstream of a melting vessel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, devices and methods will be described in more detail with reference to the accompanying drawings in which exemplary embodiments of the present disclosure are shown. Whenever possible, the same reference numbers are used throughout the drawings to indicate the same or like parts. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Unless otherwise indicated, the drawings may not be to scale or to scale from one drawing to another.

Ranges may be expressed herein as from “about” one particular value and/or to “about” another particular value. When such ranges are expressed, other embodiments include from one particular value and/or to another particular value. Similarly, when values are expressed as approximations, it will be understood that by use of the preceding "about" the particular value forms another embodiment. It will be further appreciated that each endpoint of the ranges is significant in relation to the other endpoint and independently of the other endpoint.

Directional terms used herein, such as up, down, right, left, front, rear, top, and bottom, as shown, refer only to the drawings and do not imply an absolute direction.

Unless expressly stated otherwise, any method described herein should not be construed as requiring that the steps be performed in a particular order. Thus, method claims herein do not imply an order in which the steps may in fact be followed consecutively, nor are the steps specifically recited in the claims or description to be limited to a particular order. This includes all possible non-explicit grounds for interpretation, and includes: logic issues regarding the arrangement of steps or the flow of an action; plain meaning derived from grammatical construction or punctuation; The number or type of embodiments described in the specification.

The terms “substantially,” “substantially,” and variations thereof, as used herein, are intended to indicate that a described characteristic is equal to, or nearly equal to, a value or description.

While various features, elements, or steps of particular embodiments may be disclosed using the transitional phrase "comprising," alternatively, they may be described using the transitional language "consisting of" or "consisting essentially of." It should be understood that the embodiments are implied. Accordingly, alternative embodiments for a device comprising A + B + C may include embodiments in which the device consists of A + B + C and embodiments in which the device consists essentially of A + B + C.

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “one” component includes forms having two or more such components unless the context clearly dictates otherwise.

Forms of this disclosure include an apparatus for conditioning a batch into molten glass, and in particular an apparatus for conditioning molten glass. Furnaces of the present disclosure may serve a wide range of applications for heating gases, liquids and/or solids. In one embodiment, the apparatus of the present disclosure is described with reference to a glass melting system configured to melt a batch into molten glass and transport the molten glass to downstream processing equipment.

The methods of this disclosure will condition molten glass in a wide range of ways. For example, the molten glass may be conditioned by heating the molten glass to a temperature above the initial temperature, such as above the melting vessel temperature. In other examples, the molten glass may be conditioned by reducing the rate of heat loss caused by controlling the cooling rate of the molten glass by maintaining the temperature of the molten glass or injecting thermal energy into the molten glass.

Methods of the present disclosure may condition molten glass by means of fining vessels, mixing vessels, or other vessels. Optionally, such device may include one or more other elements such as thermal management devices, electronics, electromechanical devices, support structures or transport vessels (conduits) that convey the molten glass from one location to another. It may include other elements to facilitate the operation of the glass manufacturing apparatus.

1 shows an exemplary glass manufacturing apparatus 10 . In some examples, such a glass manufacturing apparatus 10 may include a glass melting furnace 12 that may include a melting vessel 14 . In addition to melting vessel 14, glass melting furnace 12 optionally includes one or more other elements, such as heating elements (eg, combustion burners or electrodes) configured to heat the batch and convert the batch into molten glass. can do. In other examples, glass melting furnace 12 may include thermal management devices (eg, insulating elements) configured to reduce heat lost in the vicinity of the melting vessel. In yet other examples, glass melting furnace 12 may include electronic and/or electromechanical devices configured to facilitate melting of a batch into a glass melt. In another example, glass melting furnace 12 may include support structures (eg, support chassis, support members, etc.) or other elements.

The glass melting vessel 14 is usually constructed of a refractory material such as a refractory ceramic material. In some examples, glass melting vessel 14 may be constructed from a refractory ceramic brick, such as a refractory ceramic brick comprising alumina or zirconia. The glass melting vessel 14 may further include one or more bubblers 16 . Bubblers 16 are located at the bottom of the melting vessel and extend upward into the molten glass occupying the volume of the melting vessel. In other embodiments, such as for other containers, such bubblers may be positioned in other orientations. The bubblers 16 may be configured to introduce gases such as, but not limited to, oxygen, nitrogen, helium, argon, carbon dioxide, and mixtures thereof into the molten glass. The bubblers 16 may be located near the inlet region of the melting vessel, near the outlet region of the melting vessel, or at intermediate locations within the melting vessel.

In some examples, the glass melting furnace may be incorporated as an element of a glass manufacturing apparatus configured to manufacture a glass ribbon. In some embodiments, the glass melting furnace of the disclosure is incorporated as an element of a glass manufacturing apparatus including a slot draw apparatus, a float bath apparatus, a down-draw apparatus, an up-draw apparatus, a press-rolling apparatus, or other glass ribbon manufacturing apparatus. It can be. As an example, FIG. 1 schematically shows a glass melting furnace 12 as an element of a fusion down-draw apparatus 10 for fusion drawing a glass ribbon for subsequent processing into glass sheets.

The glass manufacturing apparatus 10 , such as the fusion down draw apparatus of FIG. 1 , may optionally include an upstream glass manufacturing apparatus 18 located upstream to the melting vessel 14 . In some examples, some or all of the upstream glass manufacturing apparatus 18 may be incorporated as part of the glass melting furnace 12 .

As shown in the illustrated example, such an upstream glass manufacturing device 18 may include a reservoir 20, a batch transfer device 22 and a motor 24 connected to the batch transfer device. Storage 20 may be configured to store a bulk batch 26 that may be fed into melting vessel 14 of glass melting furnace 12 as indicated by arrow 28 . In some examples, batch transfer device 22 may be driven by motor 24 configured to transfer a predetermined amount of batch 26 from reservoir 20 to melting vessel 14 . In other examples, motor 24 may drive batch transfer device 22 to introduce batch 26 at a controlled rate based on a sensed level of molten glass downstream of melting vessel 14 . The batch 26 in melting vessel 14 may then be heated to form molten glass 30 .

Additionally, the glass manufacturing apparatus 10 may optionally include a downstream glass manufacturing apparatus 32 located downstream to the glass melting furnace 12 . In some examples, a portion of that downstream glass manufacturing apparatus 32 may be incorporated as part of the glass melting furnace 12 . For example, the first connecting conduit 34 described below, or other parts of the downstream glass manufacturing apparatus 32, may be incorporated as part of the glass melting furnace 12. Elements of the downstream glass manufacturing apparatus including the first connecting conduit 34 may be formed of noble metal. Suitable metals include platinum group metals selected from the group consisting of platinum, iridium, rhodium, osmium, ruthenium and palladium, or alloys thereof. For example, the downstream elements of the glass manufacturing apparatus may be formed from a platinum-rhodium alloy comprising 70 to 90 weight percent platinum and 10 to 30 weight percent rhodium.

The downstream glass making apparatus 32 includes a first conditioning vessel, such as a fining vessel 36, located downstream of the melting vessel 14 and connected to the melting vessel 14 via a first connecting conduit 34 described above. can do. In some examples, molten glass 30 may be gravity fed from melting vessel 14 to fining vessel 36 via first connecting conduit 34 . For example, gravity can cause molten glass 30 to pass from melting vessel 14 to fining vessel 36 through an internal passageway of first connecting conduit 34 .

Within the fining vessel 36, bubbles may be removed from the molten glass 30 by a variety of techniques. For example, batch 26 may include one or more polyvalent compounds (ie, fining agents) such as tin oxide that, when heated, undergo a chemical reduction reaction to release oxygen. Other suitable fining agents include but are not limited to arsenic, antimony, iron and cerium. The refining vessel 36 may be heated to a higher temperature than the melting vessel 14, thereby further heating the fining agent. Oxygen bubbles produced by the temperature-induced chemical reduction of the fining agent(s) rise through the molten glass in the refining vessel, where gas within the molten glass produced in the molten glass will join the oxygen bubbles produced by the fining agent. can The enlarged gas bubbles can then rise to the free surface of the molten glass in the fining vessel and then exit through a suitable vent pipe.

The downstream glass making apparatus 32 may further include a second conditioning vessel, such as a mixing vessel 38, which may be located downstream of the fining vessel 36. The mixing vessel 38 may be used to provide a homogeneous glass melting composition, reducing or eliminating non-homogeneous cords that may be present in the molten glass. As shown, the fining vessel 36 will be connected to the molten glass mixing vessel 38 via a second connecting conduit 40 . In some examples, molten glass 30 may be gravitationally fed from refining vessel 36 to mixing vessel 38 via second connecting conduit 40 . For example, gravity causes molten glass 30 to pass from the refining vessel 36 to the mixing vessel 38 through the inner passage of the second connecting conduit 40 . In some examples, the downstream glass manufacturing apparatus 32 may include multiple mixing vessels. In some embodiments, a mixing vessel may be included upstream of the fining vessel 36 and a second mixing vessel located downstream of the fining vessel 36 . In some embodiments, mixing may be performed by a mixing device such as a static mixing vane. The static mixing vane may be located within a conduit of a downstream glass manufacturing apparatus or within another vessel of the downstream glass manufacturing apparatus.

The downstream glass manufacturing apparatus 32 may further include another conditioning vessel such as a transfer vessel 42 located downstream of the mixing vessel 38 . The delivery vessel 42 conditions the molten glass 30 to be fed to the downstream forming device. For example, delivery vessel 42 may act as an accumulator and/or flow controller to provide a controlled flow of constant molten glass 30 through delivery conduit 46 to forming body 44. there is. As shown, the mixing vessel 38 will be connected to the delivery vessel 42 via a third connecting conduit 48 . In some examples, molten glass 30 may be gravity fed from mixing vessel 38 to delivery vessel 42 via connecting conduit 48 . For example, gravity will act to pass the molten glass 30 from the mixing vessel 38 to the delivery vessel 42 through the inner passage of the third connecting conduit 48 .

The downstream glass manufacturing apparatus 32 may further include a forming apparatus 50 having the aforementioned forming body 44 comprising an inlet conduit 52 . Delivery conduit 46 may be positioned to deliver molten glass 30 from delivery vessel 42 to inlet conduit 52 of forming apparatus 50 . In the fusion molding process, the molded body 44 includes a trough 54 formed on the upper surface of the molded body and a converging molded surface 56 converging along the lower edge 58 (root) of the molded body. can do. The molten glass delivered to the forming body through the delivery vessel 42, the delivery conduit 46, and the inlet conduit 52 overflows the walls of the trough and travels down the converging forming surfaces as separate flows of molten glass. Such separate flows of molten glass combine downward along the root, creating a single ribbon of glass 60 that is drawn from the root 58 by stressing the glass ribbon by gravity and pulling rolls (not shown). and controls the dimensions of the glass ribbon by cooling and increasing the viscosity so that the glass ribbon 60 undergoes a visco-elastic transition to have mechanical properties that impart stable dimensional properties to the glass ribbon 60. . The glass ribbon will be substantially separated into individual glass sheets by a glass separation device (not shown).

Unlike the other components of the downstream glass manufacturing apparatus, the forming body 44 is typically formed from a refractory ceramic material such as alumina (aluminum oxide) or zirconia (zirconia oxide), although other refractory materials may be used. In some examples, forming body 44 is equivalently a monolithic block of ceramic material that is pressed and sintered and then machined into a suitable shape. In other examples, the shaped body is formed by joining two or more blocks of a refractory material, such as a refractory ceramic material. The forming body 44 may include one or more noble metal elements configured to direct the flow of molten glass onto and from the forming body.

2 shows a simplified schematic diagram of an example bubbler 16 according to embodiments described herein, which bubbler 16 includes a capillary member 100, a sleeve 102 and a nozzle 104. include The capillary member 100, sleeve 102 and nozzle 104 will together define a central longitudinal axis of flow 105 which defines a common central axis of the device and selected elements. The bubbler 16 supports the cooling device 106, the screw member 108, the positioning assembly 110 and the bubbler 16 to bubble the bubbler into a suitable structure, such as a steel joint or other structure. It may further include a support assembly 111 configured to fix the roller. Other elements of such an example bubbler are presented in more detail in the following description.

3 and 4 are i) a cross-sectional perspective view of the end of the bubbler 16 and ii) a longitudinal cross-sectional view of the nozzle 104, showing the capillary member 100, sleeve 102 and nozzle 104, respectively. In particular, the sleeve and/or nozzle shown in FIGS. 3 and 4 is configured to be inserted into molten glass 30 . Capillary member 100 may be formed, for example, from any refractory ceramic suitable for use in high temperature corrosive environments. In some examples, the capillary member 100 is made of aluminum oxide (eg, aloxide, aloxite or alundum) or stabilized zirconia (eg, yttria, calcium or magnesium- stabilized zirconia). The capillary member 100 can be selected to be compatible with the glass composition, such as during manufacture, so that any dissolution or corrosion of the capillary member does not significantly affect the overall glass composition. The capillary member 100 includes a plurality of capillary passages 112 extending from one end (i.e., first end 114) of the capillary member 100 to an opposite end (second end 176, see FIG. 8B). Further comprising, such capillary passages (112) are generally parallel to the central axis (105). Each capillary passage 112 is configured to limit entry of molten glass into the capillary passage as it reaches the capillary member, and each capillary passage may have a diameter ranging from about 0.02 mm to about 0.635 mm. . As used herein, the term “diameter” refers to the largest dimension in the axis of the passage perpendicular to the central axis 105 and is not strictly limited to passages of circular cross-sectional shape. For example, the capillary passage 112 may comprise a circular, rectangular or other geometric shape. Each capillary passage 112 includes an orifice 115 at the first end 114, and each capillary orifice 115 includes an area (ie, area) calculated from the dimensions of the capillary orifice. For example, if such a capillary orifice is a circular orifice, the area of the capillary orifice is the area of a circle (πr ² ), where r is the radius of the circle.

The capillary member 100 is slidably positioned within the sleeve 102 such that the capillary member 100 can be moved within the sleeve 102 along the central axis 105 as needed. The sleeve 102 will be formed of any metal that can withstand the high temperatures and corrosive environments associated with glass melting or molten glass conditioning. For example, suitable metals include the platinum group metals osmium, palladium, ruthenium, iridium, rhodium, platinum or alloys thereof. In examples, sleeve 102 may be formed from a platinum-rhodium alloy containing from about 70% to about 90% platinum and from about 10% to about 30% rhodium.

Like sleeve 102, nozzle 104 will be formed from a metal that can withstand the high temperatures and corrosive environments associated with glass melting or molten glass conditioning. For example, suitable metals include the platinum group metals osmium, palladium, ruthenium, iridium, rhodium, platinum or alloys thereof. In examples, the nozzle 104 may be formed from a platinum-rhodium alloy containing from about 70% to about 90% platinum and from about 10% to about 30% rhodium.

The nozzle 104 includes a passage 116 extending from a first orifice 120 defined by a first end 122 to a second orifice 124 defined by a second end 126 . In some embodiments, the diameter of the second orifice 124 is greater than the diameter of the first orifice 120 . The area of the first orifice 120 in a plane perpendicular to the central axis 105 is the total number of capillary passage orifices 115 to prevent flow restriction of gas exiting the bubbler through the first orifice 120. may be approximately equal to the cumulative area of That is, for a given volume exiting the capillary member 100, the size of the first orifice 120 can be selected to provide similar or identical flow conditions to the gas as the capillary member. As used herein, the orifice area is the total area of the orifice in a plane perpendicular to the central axis 105 . For example, if such capillary orifices have the same circular cross-section and the total number of capillary passages is 20, the cumulative area (ie, cumulative area) of the orifices is 20πr ² (assuming each passage has the same radius), so Accordingly, the area of the first orifice 120 is selected to be substantially 20πr ² . A practical meaning is that the area of the first orifice 120 is within 10% of the cumulative area of the capillary passages, for example within 5% or within 1%.

The nozzle 104 may further include a tapered outer surface 128 that tapers in a direction toward the first orifice 120 to limit bubble size during bubble generation. As best shown in FIG. 4 , the nozzle 104 includes a cross-sectional outer profile that tapers in a plane parallel to the central longitudinal axis 105 of the nozzle. For example, outer surface 128 may include a conical profile. In other examples, such as the example of FIG. 4 , the outer profile may include an arcuate outer profile, such as a semi-curved outer profile. Stated differently, the radius R1 between the central axis 105 and the outer surface 128 may decrease over at least a portion of the nozzle in a direction from the second end 126 to the first end 122 . The passage (116) includes a first passage (130) and a second passage (132) in fluid communication with the first passage (130), the first passage (130) terminating at a first orifice (120) , the second passage 132 terminates at the second orifice 124. In example embodiments, the second passage 132 may have a larger diameter than the diameter of the first passage 130 . In some embodiments, first passage 130 can have a substantially constant cross-sectional size (eg, diameter). In some embodiments, the passage 116 is directed from the second orifice 124 toward the first passage 130 such that the size of the second orifice 124 matches the size of the first passage 130, for example. A taper may be included in the second passage 132 . For example, the second passage 132 may include a conical profile. The first passage 130 may have a cylindrical shape.

At least a portion of the outer surface of the nozzle 104 is recessed by an amount d such that the outer diameter of the recessed surface 134 is located within the inner diameter of the first end 136 of the sleeve 102. do. For example, the bottom of the nozzle 104 may be recessed. Shoulder 138 of nozzle 104 may then be welded along seam 140 to first end 136 of sleeve 102, where shoulder 138 meets first end 136. . In exemplary embodiments, the sleeve 102 may further include plug welds 142 around the sleeve, for example at 180 degree or 90 degree intervals, the sleeve 102 having a recessed surface 134. is drilled through, and an additional weld is made by filling the drilled hole with weld metal. For example, such a plug weld can be made using a metal that is compatible with the sleeve and nozzle materials. In examples, plug weld 142 may be formed from a platinum-rhodium alloy containing from about 70% to about 90% platinum and from about 10% to about 30% rhodium.

As previously described, the capillary member 100 is slidably positioned within a longitudinally extending passage inside the sleeve 102, the first end 114 of the capillary member 100 being the first end of the nozzle 104. It may be arranged to abut the second end 126 . The second passage 132 is sized such that each passage of the plurality of capillary passages 112 opens into the second passage 132 . Accordingly, the second passage 132 is for receiving the flow of gas from the capillary member 100 after the gas flow enters the first passage 130 and before exiting the nozzle 104 through the first orifice 120. An intermediate chamber may be formed.

2, 5a, 5b and 6-7, the bubbler 16 may further include a cooling device 106. The cooling device 106 may be a fluid cooling device in which a cooling fluid, such as water, flows through passages within the cooling device. The cooling device 106 may include an inlet 144 and an outlet 146 through which cooling fluid may be supplied to or withdrawn from the cooling device 106 , respectively, as indicated by arrow 148 . The cooling device 106 may include lugs 150 located on and extending from the outer wall of the cooling device to control the insertion depth of the bubbler into the container. The cooling device 106 may further include an inner wall 152 defining a central passage through which the sleeve 102 and the capillary member 100 extend. The perspective view of FIG. 6 shows the cooling device 106 without the sleeve 102 and nozzle 104, and the perspective view of FIG. 7 shows the top of the cooling device 106 with the sleeve 102 and nozzle 104 in place. indicate The sleeve 102 is cooled at the upper end of the cooling device 106, for example by welding 154 between the sleeve 102 and the cooling device 106 such that a portion of the sleeve 102 extends from the top of the cooling device 106. It may be secured to device 106 .

Cooling device 106 is formed from high temperature steel, such as suitable stainless steel, and generally the top 156 of cooling device 106 on lug 150 is closest to the vessel (eg, melting vessel 14). A portion of may be coated with a refractory coating 158, such as a plasma-sprayed zirconia coating, to prevent oxidation. Additionally, the portion of the sleeve 102 located within the cooling device 106 and extending through its central passage, such as length 157 shown in FIG. To prevent diffusion welding of the sleeve to 152, it may be coated with a ceramic coating (159; see FIG. 5B) such as plasma-sprayed zirconia.

It will be readily seen from these figures that at least a portion of the sleeve 102 extends over the cooling device 106 and is not directly cooled by the cooling device. That is, the portion of the bubbler 16 extending into the molten glass, in particular the top of the sleeve 102, is not surrounded by the cooling device. Therefore, the nozzle 104, part (upper part) of the sleeve 102, and part of the capillary member 100 are not cooled by the cooling device 106.

Reference is now made to FIGS. 8A , 8B and 9 , where FIG. 8B is a downward continuation of FIG. 8A , wherein the sleeve 102 has a full flange 160 extending from the second end 162 (bottom) of the sleeve 102 . ). Fitting 164 can be used to secure sleeve 102 in passage 166 of screw member 108 via flange 160, wherein flange 160 is positioned within and extends into passage 166. One or more sealing gaskets 172 are pressurized. Passage 166 extends throughout screw member 108 , from first end 174 to second end 176 (see FIG. 8B ). For example, fitting 164 may be a threaded fitting that is screwed into first end 174 of passage 166 . Thus, passage 166 will include a thread in a first portion of passage 166 that engages threaded fitting 164 . Compression of the one or more sealing gaskets 172 by the fitting 164 causes the one or more sealing gaskets 172 to press against the capillary member 100 and the sealing lip 173, thereby sealing the sealing screw member 108. pressurizes the flowing gas between the screw member and the capillary member. After assembly, the inner wall 152 of the cooling device 106 will be secured to the fitting 164 by welding 178 . Thus, the screw member 108 can be firmly connected to the cooling device 106 .

As best shown by FIG. 8B showing the lower end of the screw member 108, the second end 179 of the capillary member 100 connects to the first end 180 of the gas supply tube 182 via a connector 184. ) is connected to Connector 184 may be a gas-tight connector. The gas supply tube 182 may be, for example, a stainless steel pipe including a central passage 186 . The connector 184 includes a passage 188 allowing gas flow between the gas supply tube 182 and the capillary member 100 . 8B and 10A, bearing block 190 is engaged with screw member 108 via thread 192 and matching threads within the passage of bearing block 190 through which screw member 108 extends. . Bearing block 190 forms part of positioning assembly 110 . To prevent binding and abrasion and promote smooth screwing, the bearing block 190 may be formed from a softer, corrosion-resistant metal than the screw member 108. For example, the bearing block 190 may be formed of silicon bronze, and the thread 192 may be a trapezoidal thread such as an Acme thread.

10B is a perspective view of the positioning assembly 110, a continuation of the downward direction of FIG. 10A, wherein the bearing block 190 is engaged with the screw member 108 and is rotatable relative to the screw member. In addition, the positioning assembly 110 may include a casing 196 connected to the bearing block 190 . 10B shows the lower part of the casing 196. Casing 196 includes a bearing assembly 198 coupled to casing 196 and a collar 200 coupled to bearing assembly 198 . A gas supply pipe 182 extends over the bearing assembly 198 and the collar 200, and the collar 200 may be connected to the gas supply pipe 182 by suitable fasteners such as screws 202. . Thus, the gas supply pipe 182 is rotatably connected to the positioning assembly 110 . The gas supply pipe 182 is further connected via suitable connectors and fittings to a gas line 204 , which is in fluid communication with a gas source 206 .

It will be readily apparent from the foregoing description and accompanying drawings that gas line 204 is in direct fluid communication with nozzle 104 via gas supply pipe 182, connector 184, and capillary member 100. In addition, the cooling device 106 is coupled with the glass melting furnace 12, and the gas supply pipe 182 is rotatably connected to the casing 196 via the bearing assembly 198 and the collar 200 (thereby supplying gas). When connected with the positioning assembly 110 rotatable relative to the pipe 182), the rotation of the positioning assembly 110 including the bearing block 190 and the casing 196 relative to the screw member 108 is the positioning assembly ( 110) to move on the screw member 108. The positioning assembly 110 moves on the screw member 108 and the capillary member 100 also moves within the sleeve 102, raising or lowering depending on the direction of rotation of the positioning assembly.

The positioning assembly 110 can be rotated manually by hand, and the positioning assembly 110 can be engaged with a driving device (not shown) to rotate the positioning assembly. For example, such a drive device includes a worm drive, wherein one of the bearing blocks 190 or another part of the positioning assembly 110 is fitted by a worm gear, which worm gear is coupled to a motor. fastened with a screw The drive device may be operated manually, or a control system (not shown) may be employed to activate the drive device at a predetermined time.

Optionally, gas is delivered to bubbler 16 under pressure from gas source 206 and the gas pressure in nozzle passage 116 is maintained slightly greater than the pressure exerted by the molten glass on the bubbler. Such required pressure will depend on variables such as the density of the molten glass 30 and the depth of the molten glass above the bubbler (output) orifice 120 . The gas pressure is applied to valve 208, e.g., a needle valve, and flow meter 210 (see FIG. 1) at a pressure suitable to release 0 to 100 bubbles from bubbler 16 into molten glass 30. can be controlled by Advantageously, the bubbler 16 is provided so that the gas pressure can be reduced below the appropriate pressure required for bubbling, either by intentional deactivation of the bubbler (eg, turning off the gas supply) or by unintentional line breakage. It can last for a considerable amount of time. For example, in the desired bubbling-free idle state, the pressure in the first passage 116 can be maintained at the same pressure exerted by the depth of the molten glass above the bubbler 16. Under such equilibrium conditions, the bubble rate will be zero bubbles per minute. Molten glass will not enter through passage 116 and will not contact capillary member 100 . On the other hand, if the gas supply to the bubbler 16 is reduced below the pressure required to prevent entry of the molten glass into the passage 116, the passage 116 may come into contact with the capillary member 100. can be filled with However, since the top of bubbler 16, e.g., nozzle 104, is not cooled, the molten glass in the nozzle (ie passage 116) remains fluid. When the gas pressure in the system, in particular the gas pressure in the capillary member 100, recovers to a level higher than the pressure applied by the molten glass on the bubbler, the molten glass is extruded from the passage 116 (or the capillary passage 112), and the bubble Either the ring will restart, or the bubbler will return to idle with the nozzle 104 pressurized, but to essentially zero bubble rate. When the molten glass contacts the capillary member 100 for a time sufficient to cause deterioration of the capillary member 100, the capillary member may be lifted within the sleeve 102 via the positioning assembly 110. Thus, bubbler 16 provides the ability to intentionally or unintentionally end bubbling for an indefinite period of time, and then restart bubbling when desired without the need to remove or rebuild the bubbler.

Conventional bubblers that rely on cooling to protect bubbler elements exposed to molten glass may suffer from the inability to clear passages filled with such molten glass. As molten glass enters the passages of the bubbler, the glass cools to a low viscosity, which can impede its ability to forcibly extrude the glass in the passages. Blocking the cooling to reduce the risk of viscosity of the glass damages the bubbler structure intended to be protected by the cooling. Therefore, common practice is to replace such bubblers.

11 shows another example of a glass manufacturing apparatus 10, wherein the glass manufacturing apparatus includes a downstream manufacturing apparatus 32 and is positioned between the melting vessel 14 and the fining vessel 36 and is formed in a conduit 214. and a molten glass conditioning vessel 212 in fluid communication with the melting vessel 14 via the molten glass conditioning vessel including one or more bubblers 16 according to embodiments of the present disclosure. Conditioning vessel 212 may, for example, constitute a cooling vessel in which the molten glass from melting vessel 14 is cooled to a temperature below the melting temperature, allowing one or more fining agents within the molten glass to change their redox state. there is. Thus, such fining agents may be “recharged” with oxygen provided by one or more bubblers 16 prior to entering fining vessel 36 . Conditioning vessel 212 may be a secondary melting vessel, such as a melting vessel having multiple temperature zones. Alternatively or optionally, fining vessel 36 may include one or more bubblers 16 .

12 shows another glass manufacturing apparatus 300 having a melting vessel 302 comprising a melting section 304 and a refining section 306 separated by a wall 308 having one or more passages therethrough. shows a schematic diagram of a part of Bubblers 16 will be included within melting section 304 . Alternatively or optionally, the purification section 306 may include one or more bubblers 16 .

It will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments of the present disclosure without departing from the spirit and scope of the present invention. Accordingly, it is intended that this disclosure cover modifications and variations of such embodiments within the scope of the accompanying claims and their equivalents.

Claims (28)

An apparatus for conditioning molten glass, said apparatus comprising:
A vessel comprising an interior volume and a bubbler extending into the interior volume;
The bubbler is:
a sleeve including an internal passageway extending therethrough;
a nozzle fixed to the first end of the sleeve and including an inner passage extending between an inlet orifice and an outlet orifice; and
A molten glass conditioning apparatus comprising: a capillary member including a plurality of capillary passages extending therethrough and slidably engaged within an interior passage of the sleeve. The method of claim 1,
A molten glass conditioning device, further comprising a cooling device. The method of claim 2,
A molten glass conditioning device further comprising a screw member coupled to the cooling device. The method of claim 1,
A molten glass conditioning apparatus further comprising a screw member connected to the sleeve. The method of claim 4,
A molten glass conditioning apparatus further comprising a positioning assembly rotatably connected to the screw member. The method of claim 5,
wherein the capillary member is connected to a gas supply pipe. The method of claim 6,
wherein the gas supply pipe is rotatably connected to the positioning assembly. The method of claim 1,
wherein the nozzle comprises an outer profile that tapers in a direction toward the exit orifice. The method of claim 3,
wherein the internal passage of the nozzle includes an intermediate chamber having a diameter greater than the diameter of the exit orifice. The method of claim 1,
The molten glass conditioning apparatus of claim 1 , wherein the nozzle includes a recess located within the inner passage of the sleeve. A method of conditioning molten glass, said method comprising:
flowing the molten glass into or out of the vessel; and
pressurizing the nozzle with gas supplied through the capillary member;
the vessel having a bubbler extending into the molten glass and including an exit orifice, the bubbler including a sleeve, a nozzle and a capillary member slidably positioned in the sleeve;
wherein the pressure of the gas prevents the molten glass from entering the nozzle and contacting the capillary member. The method of claim 11,
After pressurizing the nozzle, depressurizing the nozzle so that molten glass enters the nozzle, and then pressurizing the nozzle again to extrude the molten glass from the nozzle. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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