JP2016183070A - Support roll, glass manufacturing apparatus, and glass manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support roll capable of reducing heat removal by controlling properly cooling of a rotor in a high temperature range, and holding properly glass by the rotor.SOLUTION: In a support roll of a molten glass ribbon conveyed into a heat treatment furnace having a rotary shaft part having a hollow structure to be inserted into an opening part of a side wall of the heat treatment furnace, and a rotor provided on the tip part of the rotary shaft part, supporting the molten glass ribbon, and having a hollow structure inside, a high heat medium is circulated through each hollow part of the rotary shaft part and the rotor.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a support roll, a glass manufacturing apparatus, and a glass manufacturing method.

  For example, a float method is widely used as a method for forming the glass strip. This float method is a method in which a molten glass introduced on a molten metal (for example, molten tin) accommodated in a bathtub is caused to flow in a predetermined direction to form a molten glass ribbon in a strip shape.

  As another molding method, a fusion method is also known. In the fusion method, the molten glass that overflows from the upper edges of the left and right sides of the bowl-shaped member flows down along the left and right sides of the bowl-shaped member, and is joined at the lower edge where the left and right sides meet. This is a method of forming a glass ribbon.

  A molten glass ribbon in a state thinner than the equilibrium thickness tends to shrink in the width direction. If the molten glass ribbon contracts in the width direction, the thickness of the plate glass formed as a product becomes thicker than the target thickness. In recent years, plate glass with a thin target thickness has been put into practical use, and this problem is directly related to the quality of plate glass.

  Conventionally, in order to suppress the shrinkage | contraction of the width direction of a molten glass ribbon, the support roll which supports a molten glass ribbon is used. That is, the rotating body is installed at the tip of the support roll, the rotating body is brought into contact with the surfaces of the edges on both sides of the molten glass ribbon, the molten glass ribbon is held down, and the rotating body is rotated. Shrinkage of the molten glass ribbon in the width direction is suppressed by the grip force.

  In the support roll as described above, since the rotating body located at the tip portion is in direct contact with the high-temperature molten glass ribbon, the temperature may rise remarkably during use in an uncooled state. Therefore, the rotating body is usually cooled by circulating cooling water through the rotating body having a hollow structure of the support roll (see, for example, Patent Document 1).

International Publication No. 2010/147189

  In the technique of Patent Document 1, the temperature of the rotating body is cooled by cooling water. The temperature of the water used for the cooling water must be set to a relatively low level, usually about 20 ° C to 30 ° C. This is because if the cooling water of 60 ° C. or higher is used, the cooling water evaporates when the rotating body is used.

  In recent years, for example, when a thin glass sheet such as a liquid crystal panel is manufactured, the thickness of the molten glass ribbon flowing in the bathtub has also been reduced.

  Naturally, the molten glass ribbon having a small thickness has a small heat capacity. When a rotating body cooled by low-temperature cooling water comes into contact with such a molten glass ribbon, the surface of the molten glass ribbon is locally excessively cooled (heat-dissipated) and becomes hard. Then, the grip force to the molten glass ribbon of a rotary body falls, and there exists a problem which the suppression force of the shrinkage | contraction of the width direction will reduce.

  In particular, in the downstream area in the bathtub where the temperature is relatively low, the molten glass ribbon is harder than in the upstream area, so that the excessive cooling problem greatly affects the quality of the plate glass.

  In addition, there is a problem that insertion of a water-cooled rotating body into the melting tank increases heat removal by the rotating body and increases energy consumption.

  The present invention has been made in view of the above problems, and can appropriately manage cooling of the rotating body in a high temperature range to reduce heat removal, and the supporting roll can appropriately hold the glass, It is providing a glass manufacturing apparatus and a glass manufacturing method.

In order to solve the above problems, according to one aspect of the present invention,
A support roll used to suppress shrinkage in the width direction of the molten glass ribbon conveyed into the heat treatment furnace,
A rotating shaft having a hollow structure inserted through the opening of the side wall of the heat treatment furnace;
A rotating body that is provided at the tip of the rotating shaft, supports the molten glass ribbon, and has a hollow structure inside;
A support roll is provided in which a high heat medium is circulated in the rotating shaft and the hollow portion of the rotating body.

  According to one aspect of the present invention, the support roll, the glass manufacturing apparatus, and the glass manufacturing that can appropriately manage the cooling of the rotating body in a high temperature range to reduce the heat removal and that the rotating body can hold the glass appropriately. Can provide a method.

It is a partial cross section figure which shows the strip | belt-shaped glass manufacturing apparatus which concerns on one Embodiment of this invention. It is sectional drawing along the II-II line of FIG. It is sectional drawing which showed roughly the structure of the front-end | tip part of the support roll which comprises the strip | belt-shaped glass manufacturing apparatus which concerns on one Embodiment of this invention. It is the schematic which shows the whole structure of a support roll. It is sectional drawing which shows the structure of the connection location of the cooling casing which coat | covers the outer peripheral surface of a support roll, and a heat insulation casing. It is a figure explaining the test furnace which measures the surface temperature of the rotary body which comprises a support roll. It is a graph which shows the relationship between the surface temperature of the rotary body in Example 1-Example 5, and the comparative example 1, and the temperature of a high-heat medium. It is a figure explaining the test furnace which performs the glass contact evaluation of the rotary body which comprises a support roll. It is a table | surface which shows the glass contact evaluation result in Example 6- Example 8 and Comparative Example 2- Comparative Example 4. FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and description thereof is omitted. In this specification, “to” representing a numerical range means a range including numerical values before and after the numerical range. The glass manufacturing apparatus of the present invention can be applied to a manufacturing method such as a float method or a fusion method. Hereinafter, the float method will be described as an example. Therefore, hereinafter, the glass manufacturing apparatus is referred to as a strip glass manufacturing apparatus.

(Strip glass manufacturing device and strip glass manufacturing method)
FIG. 1 is a partial cross-sectional view showing a strip glass manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

  The strip glass manufacturing apparatus 10 has a float bath 20. A float bath 20 (corresponding to a heat treatment furnace) is connected to a bathtub 22 containing a molten metal (for example, molten tin) S, a side wall 24 arranged along the outer peripheral upper edge of the bathtub, and connected to the side wall 24 above the bathtub 22. The ceiling 26 is covered. A plurality of bricks 22 a are laid in the bathtub 22. A gas supply path 30 for supplying a reducing gas is provided in a space 28 formed between the ceiling 26 and the space 26. A heater 32 as a heating source is inserted into the gas supply path 30, and a heat generating portion 32 a of the heater is disposed above the bathtub 22.

  The manufacturing method using the manufacturing apparatus 10 is a method of forming a belt-shaped molten glass ribbon G by causing molten glass introduced onto the molten metal S to flow in a predetermined direction. The molten glass ribbon G is cooled in the process of flowing in a predetermined direction (in the direction of arrow X in FIG. 2), then pulled up from the molten metal S by a lift-out roll, gradually cooled in the slow cooling path, and strip glass ( Sheet glass).

  The space 28 in the float bath 20 is filled with a reducing gas supplied from the gas supply path 30 in order to prevent the molten metal S from being oxidized. The reducing gas contains, for example, 1 to 15% by volume of hydrogen gas and 85 to 99% by volume of nitrogen gas. The space 28 in the float bath 20 is set to a pressure higher than the atmospheric pressure in order to prevent air from entering through the gaps between the side walls 24 and the like.

  In order to adjust the temperature distribution in the float bath 20, a plurality of heaters 32 are provided at intervals in the flow direction (arrow X direction) and the width direction (arrow Y direction) of the molten glass ribbon G, for example, and arranged on the matrix. Has been. The output of the heater 32 is controlled so that the temperature of the molten glass ribbon G gradually decreases from the upstream side toward the downstream side in the flow direction (arrow X direction) of the molten glass ribbon G. The output of the heater 32 is controlled so that the temperature of the molten glass ribbon G is uniform in the width direction (arrow Y direction).

  The strip glass manufacturing apparatus 10 has a support roll 40 that suppresses the molten glass ribbon G in the float bath 20 from contracting in the width direction (arrow Y direction). As shown in FIG. 2, a plurality of pairs of support rolls 40 are arranged on both sides in the width direction of the molten glass ribbon G, and tension is applied to the molten glass ribbon G in the width direction (arrow Y direction). The support roll 40 of this embodiment can be suitably implemented especially on the downstream side where the temperature of the molten glass ribbon G is decreasing and becoming hard. Of course, it can also be carried out on the upstream side.

(Support roll)
Next, the support roll 40 will be specifically described with reference to FIGS.

  Here, although the support roll used for suppression of the shrinkage | contraction of the molten glass ribbon G in the width direction in a float forming method is demonstrated to an example as an example, this invention is not limited to this.

  Moreover, in this invention, a support roll means what contacts the glass conveyed in a predetermined direction, and supports glass. The support roll may not always contact the glass, and may contact the glass when the flow of the glass is disturbed. Examples of the glass include a molten glass ribbon having a flat part and both side edges thicker than the flat part, and a glass sheet formed by cutting out both side edges of the glass ribbon.

  Further, the support roll may have at least one of a function of forming the glass into a desired shape, a function of assisting the conveyance of the glass, and a function of regulating a position in a direction perpendicular to the conveyance direction of the glass. Good. Here, the conveyance direction of the glass may be a horizontal direction, a vertical direction, or an oblique direction. Further, the direction perpendicular to the glass conveyance direction may be either a direction perpendicular to the glass main surface or a direction parallel to the glass main surface (side surface direction).

  FIG. 3 is a cross-sectional view schematically showing the configuration of the tip portion of the support roll constituting the belt-shaped glass manufacturing apparatus.

  The support roll 40 has a rotary shaft 50 having a hollow structure that is inserted through the opening of the side wall 24 of the float bath 20, and a rotary body 60 provided at the tip of the rotary shaft 50. The rotating body 60 supports the end of the molten glass ribbon G in the width direction so that the molten glass ribbon G does not contract in the width direction by biting into or contacting the upper surface of the molten glass ribbon G. Therefore, the molten glass ribbon G can be sent out in a predetermined direction by the rotation of the rotating shaft portion 50. While the rotating body 60 is in contact with the molten glass ribbon G, the rotating shaft portion 50 is not in contact with the molten glass ribbon G.

  As shown in FIG. 3, the rotating body 60 has a hollow structure in which a metal material such as carbon steel or a heat-resistant alloy is formed in a substantially disk shape, and has a space 600 through which a high-heat medium described later flows. The rotating body 60 has two rows of gear shapes formed along the entire outer circumference of the disk and has two rows of protrusions on the outer circumference, but this is not restrictive. In the figure, the protrusion has a triangular cross section, but the present invention is not limited to this. For example, it may be rectangular or semicircular.

  The rotating shaft portion 50 is formed of a metal material such as carbon steel or a heat-resistant alloy, and has a heat medium flow path therein. A high heat medium is supplied to the heat medium flow path.

  That is, the rotating shaft portion 50 has, for example, a double tube structure, and includes an inner tube 51 and an outer tube 52 that extend along the direction of the central axis J.

  The inner tube 51 and the outer tube 52 have a hollow structure, and heat is generated by an inner space 510 of the inner tube 51 and an outer space 520 formed between the outer peripheral surface of the inner tube 51 and the inner peripheral surface of the outer tube 52. A medium flow path is configured.

  A drive control device 400 having a reduction mechanism such as a gear, a pulley, and a timing belt, and a drive device such as a motor is connected to the end of the rotary shaft portion 50 opposite to the rotating body 60 (see FIG. 4). ). Therefore, the drive control device 400 can control the speed reduction mechanism by the drive device and rotate the rotating body 60 at a predetermined rotation speed via the outer tube 52 of the rotation shaft portion 50.

  As for the support roll 40 of the said structure, the rotary body 60 is cooled with a high heat medium. For example, the high heat medium passes through the inner space 510 of the inner pipe 51, reaches the space 600 of the rotating body 60, and then flows through the outer space 520. Of course, the high heat medium may be distributed in the reverse direction described above. Inside the support roll 40, a heat medium flow path of a high heat medium is formed by a flow path through the inner space 510 of the inner tube 51, the space 600 of the rotating body 60, and the outer space 520.

  The high heat medium supplied to the heat medium flow path of the support roll 40 uses heat medium oil. Like the conventional cooling water, the heat medium oil is extremely unlikely to evaporate in the heat medium flow path. Therefore. The temperature can be set higher than in the past, for example, the heat medium oil set in a high temperature range of 50 ° C. to 300 ° C. is circulated in the heat medium flow path, and the support roll 40 is appropriately cooled. Can do.

  Further, the high heat medium is not limited to only the heat medium oil, and any high temperature medium that does not separate or evaporate in the temperature range to be used can be suitably used. For example, examples of the high-temperature medium other than the heat transfer oil include an organic high-temperature medium such as naphthalene and an inorganic heat medium such as various salts and molten metals.

  The support roll 40 has temperature adjustment means for adjusting the temperature of the supplied high heat medium, and is adjusted to an appropriate temperature according to the location of the support roll 40 (upstream or downstream of the float bath 20). The high heat medium that has been produced is supplied. The temperature adjusting means may be provided for each of the upstream region, the midstream region, and the downstream region, or may be provided for each support roll 40.

  As described above, the support roll 40 of the present embodiment can cool the rotating body 60 with a high-temperature heat transfer oil, so that the outer peripheral surface of the rotating body 60 can be kept at an appropriate temperature without being excessively cooled.

  Therefore, when the outer peripheral surface of the rotating body 60 comes into contact with the surface of the molten glass ribbon G at around 1000 ° C., it prevents the heat from being generated and becomes hard, and the gripping force of the rotating body 60 to the molten glass ribbon G is reduced. It is possible to solve the problem of lowering, suppressing the wrapping (stick) around the rotating body 60 and the shrinkage suppressing force in the width direction of the molten glass ribbon. Further, since the rotating body 60 is not excessively cooled, the occurrence of defects caused by the molten metal vapor contained in the float bath atmosphere coming into contact with the rotating body 60, solidifying, and dropping onto the surface of the molten glass ribbon can be reduced.

  In particular, the downstream region in the float bath 20 having a relatively low temperature is effective because the molten glass ribbon G is harder than the upstream region.

  Next, the structure of the outer peripheral surface of the rotating shaft part 50 which comprises the support roll 40 is demonstrated based on FIGS. FIG. 4 schematically shows the overall configuration of the support roll 40. FIG. 5 is an enlarged cross-sectional view showing the connection location between the cooling casing and the heat insulation casing of the support roll 40.

  As shown in FIG. 2, the outer peripheral surface of the support roll 40 is disposed outside the float bath 20 and a high heat region 40 </ b> A in which a part is disposed in the float bath 20 and the rotating body 60 is provided at the end. There is a low heat region 40B provided with the drive control device 400 at the end. Of the outer peripheral surface of the rotating shaft portion 50 of the support roll 40, the high heat region 40 </ b> A is disposed in the float bath 20 and needs to be appropriately cooled. On the other hand, the low heat region 40B is a work region where an operator or the like may come into contact. Therefore, in this embodiment, the part where the high-temperature heat transfer oil of 50 ° C. to 300 ° C. in the low heat region 40B is circulated is managed at a temperature that does not cause a problem even if a person comes into contact with the heat insulating structure. As a result, it is possible to prevent a disaster such as a person coming into contact with the low heat region 40B and causing burns, and the maintenance work is facilitated. In addition to the heat insulating structure, the low heat region 40B may be provided with cooling means such as water cooling or air cooling in whole or in part.

  In view of the above points, the rotary shaft portion 50 of the support roll 40 of the present embodiment is configured so that the outer peripheral surface thereof is covered with a hollow cooling casing 70 and a hollow heat insulating casing 80.

  The cooling casing 70 is provided in the high heat region A on the outer peripheral surface of the rotating shaft portion 50, and the heat insulating casing 80 is provided in the low heat region B on the outer peripheral surface of the rotating shaft portion 50.

  As shown in FIG. 3, the cooling casing 70 has a rotating shaft portion 50 as an inner tube, and has a space 700 therein. The space 700 is supplied with a high heat medium. In the illustrated example, the upper side is the forward path, and the lower side is the backward path. As shown in FIG. 5, the high heat medium supply means 72 into the space 700 is provided at the upper position of the cooling casing 70, and the discharge means 73 is the lower position. It is because it is provided in the position. Therefore, the supply means 72 and the discharge means 73 may be reversely arranged so that the forward path and the backward path are reversed. The high heat medium to be supplied is the same as the high heat medium supplied to the support roll 40, and is a heat medium oil within 50 ° C to 300 ° C.

  Since the high heat medium supplied to the cooling casing 70 is the same as the high heat medium that cools the support roll 40, the high heat medium that circulates in the heat medium flow path formed in the rotating shaft portion 50 and the rotating body 60 is used. It can prevent that temperature falls. Therefore, a constant high temperature can be supplied to the rotator 60, and heat removal from the float bath 20 can be reduced.

  The cooling casing 70 may hold the bearing 71 at the tip. Since the bearing 71 rotatably supports the outer tube 52 of the rotating shaft portion 50, the bending of the rotating shaft portion 50 due to gravity can be suppressed. The front end portion of the cooling casing 70 is an end portion on the rotating body 60 side of both end portions in the longitudinal direction of the cooling casing 70. Incidentally, as shown in FIG. 3, the rotating body 60 is disposed outside the cooling casing 70.

  As shown in FIGS. 4 and 5, the above-described heat insulation casing 80 has the rotary shaft portion 50 as an inner tube, and has a space 800 inside. The space 800 may be filled with a heat insulating member 81. The cooling casing 70 and the heat insulating casing 80 are made of metal such as carbon steel or a heat resistant alloy, and are disposed for each rotary shaft portion 50.

  The cooling casing 70 and the heat insulation casing 80 are connected by a misalignment prevention means 90. The misalignment prevention means 90 includes a flange member 91 connected to the outer periphery of the end of the cooling casing 70 on the side opposite to the rotating body at the connecting portion of the cooling casing 70 and the heat insulating casing 80 and the end of the heat insulating casing 80 on the rotating body side. And a flange member 92 connected to each other. The flange member 91 and the flange member 92 have a taper structure corresponding to the shape of the surfaces that contact each other at the connecting portion, and are fitted with bolts 93 and nuts 94 to prevent misalignment.

  The misalignment prevention means 90 is not limited to this. Typically, other misalignment prevention means used for connecting steel pipes can be applied. The heat-insulating casing 80 is connected to the drive control device 400 at the end opposite to the rotating body 60. Since the speed reduction mechanism, the drive device, and the like of the drive control device 400 are exposed, it is preferable to appropriately perform cooling such as applying cooling water or applying fan wind.

  As described above, the outer peripheral surface of the rotating shaft portion 50 of the support roll 40 is divided and covered with the cooling casing 70 and the heat insulating casing 80, so that the temperature of the high heat medium is appropriately maintained while the operator Can be secured.

<Manufacturing method>
Next, with reference to FIG. 1 and FIG. 2 again, a method for manufacturing a glass strip using the glass ribbon manufacturing apparatus 10 having the above-described configuration will be described.

  The strip glass manufacturing method includes a molding step in which the molten glass ribbon G is continuously supplied onto the molten metal S in the bathtub 22 and the molten glass ribbon G is formed on the molten metal S into a plate-shaped strip glass.

  The molten glass ribbon G gradually hardens while flowing on the liquid surface of the molten metal S. The band-shaped glass ribbon G is pulled up from the molten metal S in the downstream area of the float bath 20 and is conveyed toward a slow cooling furnace installed on the downstream side. Since both side edge portions of the belt-like glass ribbon G are thicker than the flat portion on the inside thereof, they are cut off after slow cooling. Thereby, a strip-shaped glass (float glass) having a substantially uniform plate thickness is obtained.

  According to the present embodiment, in the molding process, the process of circulating a high heat medium in the hollow shaft of the hollow structure rotating shaft 50 and the hollow structure rotating body 60 constituting the support roll 40 is performed.

  In particular, when the high heat medium is a heat medium oil of 50 ° C. to 300 ° C., the rotating body 60 can be cooled while maintaining an appropriate temperature. In the support roll 40 arrange | positioned in the downstream of the float bath 20, the heat transfer oil of 100 to 250 degreeC is more preferable, for example.

  As described above, the support roll 40 of the present embodiment can cool the rotating body 60 with a high-temperature heat transfer oil, so that the outer peripheral surface of the rotating body 60 can be kept at an appropriate temperature without being excessively cooled.

  Therefore, when the outer peripheral surface of the rotating body 60 comes into contact with the surface of the molten glass ribbon G at around 1000 ° C., it prevents the heat from being generated and becomes hard, and the gripping force of the rotating body 60 to the molten glass ribbon G is reduced. It is possible to solve the problem of lowering or reducing the suppression force of shrinkage in the width direction of the molten glass ribbon.

  In particular, in the downstream region in the float bath 20 where the temperature is relatively low, the molten glass ribbon G is harder than that in the upstream region, which is an effective cooling method.

  The thickness of the manufactured float glass is, for example, 1.0 mm or less, preferably 0.7 mm or less. That is, the thickness of the flat portion of the strip glass is, for example, 1.0 mm or less, preferably 0.7 mm or less.

  The manufactured float glass is used as, for example, a glass substrate for display, a cover glass for display, and a window glass.

The float glass produced may be alkali-free glass when used as a glass substrate for a display. The alkali-free glass is a glass that does not substantially contain an alkali metal oxide such as Na ₂ O, K ₂ O, or Li ₂ O.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

  First, the relationship between the surface temperature of the rotating body 60 of the support roll 40 in the test furnace 100 and the temperature of the high heat medium was examined using the test furnace 100 shown in FIG.

  The test furnace 100 has a bathtub 102 that accommodates a molten metal (for example, molten tin) S. The bathtub 102 is configured by laying a plurality of bricks. In the drawing, for the sake of explanation, the side wall disposed along the outer peripheral upper edge of the bathtub 102 and the ceiling connected to the side wall and covering the upper side of the bathtub 102 are omitted. As described with reference to FIGS. 1 and 2, a reducing gas is supplied to a space formed between the ceiling and a heater as a heating source is disposed above the bathtub 102.

  The support roll 40 inserted from the side wall side of the test furnace 100 is the one described in FIGS. 1 to 5. A temperature measuring device 41 for measuring the surface temperature of the rotating body 60 connected to the tip of the support roll 40 was attached.

  The temperature of the heat transfer oil supplied into the support roll 40 was set to three stages of 50 ° C to 70 ° C, 150 ° C, and 250 ° C.

  Moreover, the furnace temperature was set in five stages of 850 ° C., 900 ° C., 950 ° C., 1000 ° C., and 1050 ° C. At this time, the temperature of the molten metal S in the test furnace 100 is substantially the same as the temperature in the furnace.

  And the support roll 40 which each supplied the heat carrier oil set to the temperature of three steps for every furnace temperature was inserted in the test furnace 100, and the surface temperature of the rotary body 60 of the support roll 40 was measured. Incidentally, the heat transfer medium oil of the same temperature range is sequentially supplied also to the cooling casing 70.

  FIG. 7 shows the measurement results of the surface temperature of the rotating body 60 at the furnace temperature and the temperature of the high heat medium. In addition, as Comparative Example 1, the temperature results of the surface of the rotating body when a commonly used support roll was used and the furnace temperature was 1000 ° C. and the cooling water temperature was 30 ° C. were also shown. This support roll has substantially the same structure as the support roll 40 of the present embodiment, and is different in that the outer peripheral surface of the rotating shaft portion is covered with a casing provided with a cooling means such as cooling gas.

  The vertical axis indicates the temperature of the high heat medium (heat medium oil), and the vertical axis indicates the temperature of the rotating body surface. The furnace temperatures set in five stages were set as Examples 1 to 5, respectively, and the surface temperature of the rotating body 60 in each temperature zone of the high heat medium was shown in the graph.

  First, it can be seen that the temperature of the surface of the rotating body when the temperature of the high heat medium is 50 ° C. to 70 ° C. (left end in the figure) is a high temperature of about 370 ° C. to 550 ° C. in Examples 1 to 5.

  It can be seen that the temperature of the surface of the rotating body when the temperature of the high heat medium is 150 ° C. (center in the figure) is a high temperature of about 420 ° C. to 570 ° C. in Examples 1 to 5.

  It can be seen that the temperature of the surface of the rotating body when the temperature of the high heat medium is 250 ° C. (the right end in the drawing) is a high temperature of about 480 ° C. to 640 ° C. in Examples 1 to 5.

  In particular, in the furnace temperature region of 1000 ° C. (Examples 3 to 5), the temperature of the surface of the rotating body is as high as 500 ° C. to 600 ° C.

  In Comparative Example 1, the temperature of the rotating body surface when the temperature of the cooling water is 30 ° C. is a low temperature of about 120 ° C., and the molten glass ribbon is excessively cooled.

  From the above test, it has been found that the support roll 40 of the present invention can maintain the surface temperature of the rotating body at a high temperature of 350 ° C. or higher when the temperature of the heat transfer oil is within 50 ° C. to 300 ° C.

  Next, the glass contact evaluation with respect to the molten glass G of the rotary body 60 was investigated by the test furnace 100 shown in FIG.

  The used test furnace 100 is substantially the same as that shown in FIG. 6, and the used support roll 40 is also the same. Moreover, the conventional support roll H was prepared for the comparative example. The support roll H has substantially the same structure as the support roll 40 of the present embodiment, and the outer peripheral surface of the rotating shaft is covered with a casing provided with a cooling means such as cooling gas. The difference is that the cooling medium used for cooling is 30 ° C. water (cooling water).

  The point which accommodates the molten glass G on the upper surface of the molten tin S in the bathtub 102 is different from FIG. By introducing the molten glass G onto the molten tin S, the flow state of the molten glass ribbon in the float bath can be reproduced. The molten glass G used in this example is an aluminosilicate glass.

  The temperature of the high heat medium (heat medium oil) supplied into the support roll 40 was set to three stages of 60 ° C., 150 ° C., and 250 ° C. Further, the furnace temperature was set at three stages of 870 ° C., 930 ° C., and 990 ° C. assuming the downstream side of the float bath 20. At this time, the temperature of the molten metal S and the molten glass in the test furnace 100 is substantially the same as the furnace temperature. The in-furnace temperatures set in the three stages were set to Examples 6 to 8, respectively, and the following glass contact evaluation tests were performed according to the temperature of the heat transfer oil.

  In the glass contact evaluation test, support rolls 40 respectively supplied with heat transfer oil set at three stages of temperature for each furnace temperature are inserted into the test furnace 100. Then, the rotating body 60 was rotated in a state where the surface of the rotating body 60 of the support roll 40 was submerged (filled) by about 10 mm in the molten glass G, and the presence or absence of a stick and the grip property were confirmed. Confirmation of the presence or absence of a stick (adhesion) means confirming whether or not there is a phenomenon in which the molten glass G is lifted by the rotating body 60. Confirmation of grip property means confirming whether the locus of the rotating body 60 remains on the surface of the molten glass G.

  As Comparative Example 2 to Comparative Example 4, a normal support roll H was used, the furnace temperature set in three stages was set to Comparative Example 2 to Comparative Example 4, respectively, and the glass contact when the cooling water temperature was 30 ° C. Each evaluation test was conducted.

  In FIG. 9, the measurement result of the glass contact evaluation of the support roll 40 of this invention and the conventional support roll in the temperature in a furnace and the temperature of a high heat medium was shown.

  When attention is paid to Examples 6 to 8, it can be seen that the stick is not generated in any temperature range of the high heat medium (heat medium oil) and the grip property is exhibited. The * symbol in the table means that the locus of the rotating body 60 remains thin. The furnace temperature at this time is a low temperature region of 870 ° C.

  When attention was paid to Comparative Examples 2 to 4, no stick was produced at any furnace temperature, but grip performance could not be exhibited at furnace temperatures of 870 ° C. and 930 ° C.

  From the above glass contact evaluation test, it was found that the support roll 40 of the present invention can exhibit gripping properties even in a lower temperature region than the normal support roll H. Therefore, the support roll 40 of the present invention can be suitably implemented on the downstream side of the float bath 20 where the grip performance is weakened.

  As described above, the support roll according to the present invention can appropriately manage cooling of the rotating body in a high temperature region to reduce heat removal, and can reliably hold the gripping force of the rotating body.

  As mentioned above, although embodiment of a support roll, a strip | belt-shaped glass manufacturing apparatus, and a strip | belt-shaped glass manufacturing method was demonstrated, this invention is not limited to the said embodiment etc., In the range of the summary of this invention described in the claim Various modifications and improvements are possible.

  For example, the present invention can be suitably applied to other methods of forming with a strip glass. Examples of the forming method of the band glass include, for example, a down draw method, a fusion method, a slot down method, a roll forming method, a roll out method, a pulling method, and the like.

  The fusion method is also called an overflow downdraw method, in which molten glass overflowing from the left and right sides flows down along the left and right side surfaces of the bottle and is merged at the lower end of the bottle to form a strip glass. The present invention can be suitably used in a fusion molding chamber or the like.

DESCRIPTION OF SYMBOLS 10 Glass-like glass manufacturing apparatus 20 Float bath 40 Support roll 50 Rotating shaft part 60 Rotating body 70 Cooling casing 80 Heat insulation casing 90 Centering prevention means 100 Test furnace G Molten glass S Molten metal

Claims (10)

It is a support roll of a molten glass ribbon conveyed in a heat treatment furnace,
A rotating shaft portion of a hollow structure inserted through the opening of the side wall of the heat treatment furnace;
A rotating body that is provided at the tip of the rotating shaft, supports the molten glass ribbon, and has a hollow structure inside;
A support roll, wherein a high heat medium is circulated in the rotary shaft portion and the hollow portion of the rotary body.   2. The support roll according to claim 1, wherein the high heat medium supplied into the rotating shaft portion and the hollow portion of the rotating body is within a range of 50 ° C. to 300 ° C. 3.   3. The support roll according to claim 1, further comprising a temperature adjusting unit configured to adjust a temperature of the high heat medium supplied into the rotating shaft and the hollow portion of the rotating body. The outer peripheral surface of the rotating shaft portion is covered with a hollow cooling casing and a hollow heat insulating casing,
The cooling casing is
A part is arranged in the region on the rotating body side inserted into the heat treatment furnace, and the high heat medium is supplied into the hollow portion.
The insulating casing is
The support roll according to any one of claims 1 to 3, wherein the support roll is connected to the cooling casing and filled with a heat insulating material in a hollow portion.   The support roll according to claim 4, wherein the high heat medium supplied to the rotating shaft and the rotating body is the same as the high heat medium supplied to the cooling casing.   The support roll according to any one of claims 1 to 5, wherein the high heat medium is a heat medium oil.   The support roll according to claim 4, wherein a misalignment preventing means is provided at a connection portion between the cooling casing and the heat insulation casing.   The support roll according to claim 4 or 7 provided with a cooling means in at least a part of said heat insulation casing. A glass manufacturing apparatus comprising a float bath in which a molten glass ribbon is conveyed on the upper surface, and a support roll used for suppressing shrinkage in the width direction of the molten glass ribbon,
The said support roll is a support roll as described in any one of Claims 1-8, The glass manufacturing apparatus characterized by the above-mentioned.   The glass manufacturing method which has the process of shape | molding strip | belt-shaped glass, supporting glass using the support roll as described in any one of Claims 1-8.

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