JPS6348815B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses a hollow cylindrical rotating body, and uses centrifugal force,
This relates to the improvement of a device that converts glass into fibers using a jet flame stream, and it is possible to mass-produce high-quality glass fibers or so-called hard fibers while avoiding increases in energy consumption and entanglement of the produced glass fibers. The purpose of the present invention is to provide an apparatus capable of converting glass into glass fiber. Usually employed in the production of glass fibers, molten glass is discharged by centrifugal force from a large number of pores bored in the circumferential wall of a hollow cylindrical rotating body, ie, a rotor, to the outer surface of the circumferential wall. A small cone made of molten glass is formed on the outer surface of the peripheral wall, and the bottom surface is a small circle corresponding to the opening area of the pore, and a primary filament is formed at the apex of the small cone. The filament is further advanced by centrifugal force toward a jet flame stream for secondary drawing, and is secondarily stretched in the jet flame stream to be finely divided into secondary filaments that are constituent fibers of glass wool. In an apparatus for fiberizing glass using a centrifugal force and a jet flame stream using a hollow cylindrical rotating body, as shown in Fig. 7,
Pore D in upper region C of peripheral wall B of hollow cylindrical rotating body A
After being discharged from the glass fiber, the glass fiber becomes a primary filament E, which is elongated by an injected flame F and finely divided into a secondary filament G, and the peripheral wall B.
The glass fibers are discharged from the pores I in the central region H of the peripheral wall B, become the primary filament J, are drawn by the injected flame F, and are finely divided into the secondary filament K, and the glass fibers in the lower region L of the peripheral wall B After being discharged from the pore M, it becomes the primary filament N, and the injection flame F
Each glass fiber is drawn by O and entangled with the finely divided glass fiber into the secondary filament O, and the diameter of the produced glass fiber varies, resulting in poor insulation performance, compression recovery rate, and tensile strength. There are drawbacks such as deterioration of etc. In order to prevent the above-mentioned entanglement and obtain high-quality glass fibers, a relatively large amount of molten glass is discharged from the pores D in the upper region C of the peripheral wall B to form a relatively thick primary filament E, and then the drawing burner is heated. The inside of the jet flame flow F, which is ejected from the crater and is made up of an outer flame P whose speed is decreasing and an inner flame Q whose speed is high, is made to advance laterally through the jet flame F whose speed and temperature have not yet attenuated. Just before the flame Q breaks through to the outside, the inner flame Q
The secondary filament G is formed by secondarily stretching the filament G in the pores I in the central region H of the peripheral wall B to the upper region C.
Discharges slightly less molten glass than in
A primary filament J is made slightly thinner than the primary filament E, and is allowed to advance laterally in the injected flame F, and is secondarily stretched in the middle of the inner flame Q to form a secondary filament K. A relatively small amount of molten glass is discharged from the pores M, and it travels horizontally through the injection flame F as a relatively thin primary filament N, and as soon as it reaches the inner flame Q, where the velocity has significantly attenuated, it is transferred to the secondary filament. It is presumed that the secondary filament O can be obtained by drawing the filament O. On the other hand, in order to increase the production of glass fibers, the height of the peripheral wall B can be increased and the number of pores can be increased, but if this is done, the amount of heat dissipated in the lower region of the peripheral wall B will be large. There is a risk of a drop in temperature. The first method is to prevent the above-mentioned entanglement of glass fibers and also to prevent a drop in temperature in the lower region of the peripheral wall.
As a prior art, there is a technique disclosed in Japanese Patent Publication No. 42-13748. This first prior art applies induction heating by high frequency to the lower region of the peripheral wall of a hollow cylindrical rotating body,
In order to maintain the circumferential wall at a substantially uniform temperature throughout its height and to prevent the aforementioned glass fiber entanglement, the diameter of the pores in the circumferential wall is varied from the lower region through the central region to the upper region. The configuration is such that the amount of molten glass is large in the upper area, medium in the central area, and small in the lower area. As a second similar prior art, there is a technique disclosed in Japanese Unexamined Patent Publication No. 113638/1983. In this second prior art, the high-temperature molten supply glass passes through the upper inner side of the circumferential wall of a hollow cylindrical rotating body and then is distributed over the entire inner side of the circumferential wall, and the lower region of the circumferential wall is strongly heated by high frequency waves. It is configured to do this. Therefore, the temperature distribution of the peripheral wall of the hollow cylindrical rotating body is such that the temperature is highest in the lower region, the temperature is relatively low in the central region, and the temperature in the upper region is intermediate between the former two. In other words, the entire amount of high-temperature molten glass supplied by the hollow cylindrical rotating body is brought into contact with the inner upper part of the peripheral wall, and then distributed over the entire inner surface of the peripheral wall by the action of gravity and centrifugal force. It is thought that the heat brought in by the glass keeps the upper region of the peripheral wall at an intermediate temperature as described above, even though it is far from the high-frequency heating coil. The lower region of the circumferential wall is kept at the highest temperature by induction heating by a high-frequency coil. Since the central region of the peripheral wall is away from the high-frequency coil and the distributed molten glass has been subjected to a large amount of heat in the upper region, the temperature of the peripheral wall is lower than that of the upper and lower regions. It is considered a thing. In this second prior art, the following technical means are adopted in order to prevent the above-mentioned entanglement of glass fibers. That is, in the lower region of the peripheral wall of the hollow cylindrical rotating body, the peripheral wall has the highest temperature as described above, and the molten glass passing through the pores in that region also has the lowest viscosity. However, in the lower region of this peripheral wall, the primary filament of glass discharged from the pores must reach the inner flame of the injection flame and be converted into a secondary filament as soon as it reaches the inner flame of the injection flame. The molten glass discharged from the pores in the area must be small enough that the primary filaments can be attenuated into secondary filaments as soon as they reach the inner flame of the injection flame; The peripheral wall is also made thickest to lengthen the passage of the pores, thereby increasing the fluid resistance when the molten glass passes through the pores, so that only a small amount of molten glass can be discharged. In the central region of the circumferential wall of the hollow cylindrical rotating body, the bottom wall has the lowest temperature as described above, and the molten glass passing through the pores in that region has the highest viscosity. However, in the central region of this peripheral wall, the primary filament of glass discharged from the pores needs to be converted into a secondary filament in the middle of the inner flame of the injection flame, and therefore the central region of this peripheral wall The molten glass is discharged from the pores in the lower region of the peripheral wall to the extent that the primary filament reaches the middle of the inner flame of the injection flame and is finely divided into secondary filaments. It must be a moderate amount, greater than the amount of molten glass, and to achieve this, the thickness of the peripheral wall should be the thinnest and the passage through the pores should be the shortest, so that the fluid resistance as it passes through the pores is reduced. is set small so that a medium amount of molten glass is discharged as described above. As mentioned above, in the upper region of the peripheral wall of the hollow cylindrical rotating body, the temperature of the peripheral wall is between the lower region and the center region, and the molten glass passing through the pores in that region is also at a temperature between the lower region and the center region. The molten glass that passes through the pores in the area has a viscosity intermediate to that of molten glass. However, as mentioned above, in the upper region of the peripheral wall, in order to prevent entanglement with the secondary filaments discharged from the lower and central regions of the peripheral wall and made into fine fibers, the secondary filaments discharged from the pores are The volume of the glass primary filament must be large enough to be attenuated into secondary filaments just before it penetrates the inner flame of the injection flame to the outside. The thickness of the peripheral wall is set to be about the middle of the thickness of the surrounding wall, and the length of the pore passage is set to about the middle of the thickness of the surrounding wall.
Assuming that the fluid resistance when passing through the pores is intermediate,
It is configured to discharge a large amount of molten glass. Both the first prior art and the second prior art explained above,
Although it is possible to achieve the purpose of increasing production by increasing the height of the circumferential wall of the hollow cylindrical rotating body without causing entanglement of glass fibers, both methods are equipped with induction heating means using high-frequency coils. not only requires a large-capacity high-frequency generator for heating, but also requires electromagnetic shielding in the vicinity of the glass fiber forming equipment equipped with high-frequency coils to prevent danger. This method not only becomes complicated, but also has the disadvantage of deteriorating operational efficiency. In order to eliminate the above-mentioned drawbacks, there is a technique disclosed in Japanese Patent Publication No. 50-20612 as a third prior art. This third prior art uses a dedicated heating burner that brings flame into contact with the entire circumferential wall of a hollow cylindrical rotating body from the outside to heat the circumferential wall. A drawing jet device consisting of high-pressure, high-temperature steam for finely fibrillating the primary filaments formed by glass into secondary filaments must be installed separately from the heating-only burner, making the glass fiber forming device complicated and requiring high pressure , which is not preferable from the standpoint of effective use of heat because it requires a high-temperature steam generator. The three prior arts described above all use a jet heat source for finely forming a primary filament formed by molten glass discharged from the circumferential wall of a hollow cylindrical rotating body into a secondary filament. Since it requires a large-capacity heat source to heat the peripheral wall of the cylindrical rotating body, it is not suitable for the current situation where there is a strong need for energy conservation these days. On the other hand, there is a technique disclosed in Japanese Unexamined Patent Publication No. 106532/1983 as a fourth prior art which focuses on fuel saving and maintains the high quality of produced glass fibers. This fourth prior art basically has the configuration shown in FIGS. 1 and 2, in which a hollow cylindrical rotating body 2 is fixed to the lower end of a rotating shaft 1. , has a bottom wall 3, a peripheral wall 5 having a number of pores 4 for discharging molten glass, and an upper annular flange 6 formed inside the upper end of the peripheral wall 5, surrounding the rotating body 2. A drawing burner 7 is arranged, the rotating shaft 1 is arranged in an annular inner side 8 of the drawing burner 7, and the molten glass 9 is fed from a nozzle 10 through this annular inner side 8 into the rotating body 2. The elongated burner 7 injects a flame stream 14 consisting of a high-speed inner flame 12 and a relatively low-speed outer flame 13 from the crater 11. This jet flame stream 14
As will be described later, the pores 4 of the peripheral wall 5 of the rotating body 2
The primary filament formed at the tip of the small cone of molten glass discharged from the group is finely divided into secondary filaments, and the inner flame 12 has a speed capable of finely forming the secondary filaments. The speed of the outer flame 13 is attenuated to such an extent that it does not destroy the small cone of molten glass and the primary filament following it. The position of the nozzle 11 of the elongated burner 7 is selected at a position where the outer flame 13 comes into contact with the lower part of the outer surface of the peripheral wall 5 of the rotating body 2. Moreover, inside the upper annular flange 6 of the rotating body 2,
A heating burner 15 is attached, and the injection direction of the flame 16 is on the extended surface of the upper annular flange 6 and parallel to the surface of the flange 6. By contacting and passing through the upper surface or the upper and lower surfaces, heat is transferred to at least the upper annular flange 6 and the peripheral wall 5.
This is considered to be the extent of reaching the connection position with the In the fourth prior art having the above-described configuration, the molten glass 9 flowing down from the nozzle 10 with a constant flow rate controlled from the glass melting furnace (not shown) flows through the bottom wall of the rotating body 2 that is rotated at high speed by the rotating shaft 1. 3, it is distributed inside the circumferential wall 5 by the action of centrifugal force, and further discharged to the outside of the circumferential wall 5 through the pores 4 due to centrifugal force, forming a small circle corresponding to the opening surface of the pore 4 on the bottom surface. A jet flame stream 1 that forms a small cone of molten glass, is drawn into a primary filament at the apex of the small cone, and is injected from the nozzle 11 of the drawing burner 7.
The fibers are stretched to a portion of the inner flame 12 having a stretching capacity of 4, and are secondarily stretched and finely divided into secondary filaments to form glass fibers. The above-mentioned jet flame stream 14 exits the crater 11 of the elongated burner 7 and expands in width as it advances downward, and its speed is attenuated. From the viewpoint of heating the peripheral wall 5, it is preferable that the outer flame 13 be brought as close to the lower part of the outer surface of the peripheral wall 5 as possible without adversely affecting the formation of the small cone and the primary filament. However, when the inner flame 12, which has a speed capable of finely fibrillating the primary filament described above into secondary filaments, comes into contact with the outer surface of the peripheral wall 5, the molten glass discharged from the pores 4 of the peripheral wall 5 flows into the small conical shape described above. There is a thickness due to the adhesion of the molten glass that is smeared onto the outer surface of the peripheral wall 5 by the inner flame 12 and continuously discharged without having time to form the primary filament and the primary filament. If it becomes thick, it will be discharged in the form of random particles or fibers of uncontrolled thickness, and normal fiberization will not be achieved. As mentioned above, the outer flame 13 whose velocity is attenuated to the extent that it does not adversely affect the formation of the small cone of molten glass and the primary filament is moved as far as possible to the peripheral wall 5.
By bringing the peripheral wall 5 close to the lower part of the outer surface and keeping the temperature of the peripheral wall 5 high, it is possible to avoid a drop in the temperature of the molten glass passing through the pores 4, and the amount of molten glass necessary for forming a predetermined fiber is discharged from the pores 4. It is possible to do so. In the fourth prior art, the outer flame 13 of the jet flame stream 14
is brought into contact with the lower part of the outer surface of the peripheral wall 5 and the upper part of the peripheral wall 5 is also heated by the heating burner 15 to keep the peripheral wall 5 at a high temperature. When the height of the peripheral wall 5 in which the holes 4 are perforated is increased, the position of the lower end of the peripheral wall 5 becomes farther from the crater 11 of the extension burner 7,
Outer flame 1 of the jet flame stream 14 whose lower end is to be heated
In case of No. 3, it spreads too much and the amount of heat is insufficient, resulting in insufficient temperature rise. Of course, if the width of the crater 11 is widened and a large amount of fuel is supplied, the outer flame 13 can retain enough heat to raise the temperature of the lower end of the peripheral wall 5, but this is not an acceptable means for saving energy. By the way, in the fourth prior art, which aims to save fuel and produce high-quality glass fiber,
In order to increase the production amount of glass fibers, the height of the peripheral wall 5 of the rotating body 2 was increased, and the temperature distribution in the height direction of the peripheral wall 5 was the same as in the first, second, and third prior arts described above. It was confirmed through measurements that the temperature distribution in the height direction of the peripheral wall of the rotating body was different from any other. That is, the central region of the peripheral wall 5 has the highest temperature,
The upper region has a moderate temperature lower than the central region;
The lower region had the lowest temperature. This phenomenon occurs because the distance from the vent 11 of the elongated burner 7 to the lower end of the peripheral wall 5 increases, and the injected flame flow increases.
The outer flame 13 of No. 4 is diffused and does not have enough heat to raise the temperature of the lower part of the peripheral wall 5 to the required temperature, and the temperature of the part from the lower part of the peripheral wall 5 to the bottom wall 3 becomes low. It is recognized that When the high temperature molten glass 9 flowing down from the nozzle 10 comes into contact with the low temperature bottom wall 3, the viscosity of the molten glass increases due to the decrease in temperature, and the bottom wall 3
It is recognized that a highly viscous film is formed between the glass and the high-temperature molten glass that successively flows down. The high-temperature, low-viscosity molten glass that flows down one after another reaches the central region of the peripheral wall 5 without losing too much heat to the bottom wall 3 and the lower region of the peripheral wall 5, even though it comes into contact with the above-mentioned boundary film. Therefore, it is recognized that the central region has the highest temperature. The upper end of the peripheral wall 5 and the upper annular flange 6 have an air flow in the direction indicated by the arrow X in FIG. Although some cooling occurs, the upper part of the rotating body 2 is covered by a device of extension burners 7, and
The molten glass 9 flowing down from the nozzle 10 hits the bottom wall 3.
While being in contact with the above-mentioned membrane formed in the area of It is recognized that the temperature is the same. As mentioned above, based on the fourth prior art, when trying to increase the height of the peripheral wall 5 and reduce fuel consumption in order to increase the production amount of glass fiber,
It was found that the temperature distribution of the peripheral wall 5 is different from that of any of the first, second and third prior art, that is, the temperature is medium in the upper region of the peripheral wall 5, highest in the central region, and lowest in the lower region. . This phenomenon is caused by the fact that glass exhibits higher viscosity at the same temperature than glass, which is commonly used as glass fiber.
It also appears when glass fibers are produced using so-called hard glass that contains little or no alkali oxides such as NaO or K ₂ O or BaO. The present invention basically utilizes the fourth prior art described above, and increases the height of the peripheral wall to increase the production amount of glass fibers, or when producing glass fibers from so-called hard glass. The resulting unique temperature distribution of the peripheral wall, that is, the temperature distribution is the highest in the central region of the peripheral wall, the upper region of the peripheral wall is lower than the central region, and the lower region of the peripheral wall is lower than the upper region. The purpose of the present invention is to provide an apparatus that can increase the production amount of high-quality glass fiber while maintaining the same level of energy consumption. As described in claim 1, the present invention has a bottom wall, a peripheral wall having a large number of pores for discharging molten glass, and an upper annular flange located inside the upper end of the peripheral wall. A hollow cylindrical rotating body,
the elongated burner's nozzle for finely fibrillating the primary filament formed at the tip of the small glass cone discharged from the rotating body into a secondary filament; Only the outer flame part of the flow whose velocity is attenuated to the extent that it does not destroy the small glass cone is placed in a position where it contacts the lower part of the outer surface of the peripheral wall of the hollow cylindrical rotating body, and A heating burner is attached to the inside of the upper annular flange of the hollow cylindrical rotating body, and the heating burner has a flame jet direction on the extended surface of the upper annular flange and parallel to the surface of the upper annular flange. The heating degree is such that the flame contacts and passes through the upper surface or the upper and lower surfaces of the upper annular flange, and the heat reaches at least the connection position between the annular flange and the peripheral wall of the hollow cylindrical rotating body. In a centrifugal type glass fiber manufacturing apparatus, which is said to have a diameter of pores drilled in the central region of the peripheral wall, compared to the diameter of the pores drilled in the upper and lower regions of the peripheral wall. The structure is such that the diameter of the pores is small. As mentioned above, the pores in the upper region of the peripheral wall are distributed in the upper region of the peripheral wall of the rotating body, and have a slightly lower temperature and a lower viscosity than the molten glass distributed in the central region of the peripheral wall. A large amount of molten glass having a medium temperature and a medium viscosity at a slightly high temperature is discharged to form a thick primary filament, and this filament is placed close to the elongated burner's mouth and injected into an injection flame whose velocity is not attenuated. In the inner flame of the flow, it is drawn to the outer surface of the peripheral wall or to the farthest point and finely divided into secondary filaments. , its diameter is selected. The pores in the central region of the peripheral wall of the rotating body are distributed in the central region of the peripheral wall, allowing the molten glass having the highest temperature and lower viscosity to be discharged in a medium amount, smaller than in the upper region. A primary filament is formed and stretched to a position midway between the farthest position and the closest position from the surrounding wall in the inner flame of the jet flame stream whose velocity has been attenuated to some extent by moving slightly away from the elongated burner's mouth. The diameter is selected in consideration of the viscosity of the molten glass being used so that it can be finely divided into filaments and glass fibers of the target diameter can be obtained. The pores in the lower region of the peripheral wall of the rotating body are distributed to the lower region of the peripheral wall, and the molten glass that is at the lowest temperature and has the highest viscosity is discharged by contacting the low-temperature lower region and the bottom wall. Form a narrow primary filament, stretch it farthest from the elongated burner's mouth and close to the peripheral wall in the inner flame of the jet flame stream, where the velocity is considerably attenuated, and fiberize it into a secondary filament to form a filament with a target diameter. In order to obtain glass fibers, the diameter is selected in consideration of the viscosity of the glass used. More preferably, in addition to selecting the diameter of the pores, the thickness of the peripheral wall is also selected depending on the viscosity of the glass used in the upper region, the middle region, and the lower region. It is selected to be thin in the upper region, thicker in the middle region, and thinner in the lower region. Examples of the present invention will be described below. FIG. 3 shows the first embodiment, and FIG.
Only the circumferential wall 5 of the device of the fourth prior art, which has already been explained with reference to the figure, has been modified, and as shown in FIG. Pore 2 drilled in
The diameter of the pore 25 formed in the central region 24 is smaller than that of the holes 2 and 23. Figure 4 is a diagram showing the relationship between temperature and viscosity for three types of glasses, R, S and T.
is an example of a soft glass commonly used in the manufacture of glass fibers, and glasses S and T are examples of the so-called hard glasses mentioned above. The first example will be described below in comparison with the comparative example according to the fourth prior art described above. Comparative Example 1 According to the fourth prior art having the structure shown in FIGS. 1 and 2, glass fibers were produced using glass R shown in FIG. 4 with a pore diameter of 1 mm under the following conditions. (1) Height from the center of the pores 4 in the top row of the peripheral wall 5 to the center of the pores 4 in the bottom row: 30 mm (2) Number of 4 rows of pores: 30, total number of pores: 7710 (3) Glass R weighs 330 kg /h (4) Diameter of the rotating body 2: 300 mm (5) Thickness of the peripheral wall 5: 4 mm (6) Adjust the stretching burner 7 so that the average diameter of the obtained glass fibers is 7 microns As a result, the temperature of each part of the peripheral wall 5 The estimated temperature and estimated viscosity of the molten glass passing through each pore 4 are shown in Table 1, and the standard deviation of the diameter distribution of the obtained glass fibers was 3.77 microns. The fibrillation behavior of the secondary filament within the jet flame stream 14 was as shown in FIG. 7, and some tangles of glass fibers were observed.

[Table] Example 1 With the above-described configuration, glass fiber was produced using the glass R shown in FIG. 4 under the same energy usage conditions as in Comparative Example 1, and under the following conditions with the pore diameter distribution in Table 2. I did this. (1) Height from the center of the pores in the top row of the peripheral wall 19 to the center of the pores in the bottom row: 50 mm (2) Number of pore rows: 50, total number of pores: 12,850 (3) Glass R is supplied at 560 kg/h ( 4) The diameter of the rotating body 18 is 300 mm. (5) The thickness of the peripheral wall 19 is 4 mm. (6) The stretching burner 26 is adjusted so that the average diameter of the obtained glass fiber is 7 microns. As a result, the temperature of each part of the peripheral wall 19 and each pore are adjusted. The estimated temperature and estimated viscosity of the molten glass passing through it are shown in Table 2, and the standard deviation of the diameter distribution of the obtained glass fibers was 2.61 microns, indicating that high quality glass fibers were obtained. Further, the fibrillation behavior of the secondary filament 28 within the jet flame stream 27 was as shown in FIG. 3, and almost no entanglement of glass fibers was observed.

[Table] As is clear from the comparison between the first example and the comparative example described above, according to the present invention, high-quality glass fiber can be mass-produced without any increase in energy consumption. . FIG. 5 shows a second embodiment in which the rotating body 29 is made shorter than that of the first embodiment, and will be explained below in comparison with a comparative example. Comparative Example 2 Using the apparatus of the fourth prior art shown in FIGS. 1 and 2, glass fiber was produced using the so-called hard glass barrel S shown in FIG. 4, with a small diameter of 1 mm, under the following conditions. I did this. (1) Height from the center of the pores in the top row of the peripheral wall to the center of the pores in the bottom row: 30 mm (2) Number of pore rows: 30, total number of pores: 7710 (3) Glass S at 330 kg/h Supply (4) Diameter of the rotating body: 300 mm (5) Thickness of the peripheral wall: 4 mm (6) Adjust the stretching burner so that the average diameter of the resulting glass fibers is 7 microns (7) Since the glass S is a so-called hard glass, it is difficult to stretch it. A larger amount of fuel is supplied to the burner and the heating burner than when glass fibers are obtained using the glass R shown in FIG. 4, and the load on the burners is increased. As a result, the temperature of each part of the peripheral wall, the estimated temperature and estimated viscosity of the molten glass passing through each pore are as shown in Table 3, and the standard deviation of the diameter distribution of the obtained glass fibers is 4.69 microns, which is an undesirable value. It was hot. The fibrillation behavior of the secondary filament within the jet flame stream was almost the same as that shown in FIG. 7, and some fiber entanglement was observed.

[Second example 1]

With the configuration of the invention described above, the pore diameter distribution shown in Table 4 was achieved using the glass S shown in FIG. Glass fiber was produced under the following conditions. (1) Height from the center of the pores in the top row to the center of the pores in the bottom row of the peripheral wall 30 of the rotating body 29 shown in Figure 5: 30 mm (2) Number of pore rows: 30, total number of pores: 7710 (3) Supply glass S at 330 kg/h (4) Diameter of rotating body 29 300 mm (5) Thickness of peripheral wall 30 4 mm (6) Adjust stretching burner 31 so that the average diameter of the obtained glass fibers is 7 microns As a result, the temperature of each part of the peripheral wall 30 and the estimated temperature and viscosity of the molten glass passing through each pore are as shown in Table 4, and the diameter and standard deviation of the distribution of the obtained glass fibers are 2.58 microns. ,
Compared to Comparative Example 2, high quality glass fibers were obtained without an increase in energy consumption. Further, the fibrillation behavior of the secondary filament 33 within the jet flame stream 32 was as shown in FIG. 5, and almost no entanglement of glass fibers was observed.

[Second example 2]

When glass fiber was produced by slightly reducing the fuel in the drawing burner 31 in 1 of the second embodiment described above, the temperature of each part of the peripheral wall 30 and the estimated temperature and estimated viscosity of the molten glass passing through each pore were determined. teeth,
Table 5 shows that the standard deviation of the diameter distribution of the obtained glass fibers was 2.60 microns. Furthermore, the fibrillation behavior of the secondary filament within the jet flame stream was almost the same as that shown in FIG.

[Second Example 3]

Glass fibers were produced using the glass T shown in FIG. 4, with the pore diameter distribution shown in Table 6, and with the other conditions being the same as in Example 1 of the second example. The estimated temperature and estimated viscosity of the molten glass passing through the pores are as shown in Table 6.
The standard deviation of the diameter distribution of the obtained glass fibers is 2.63
microns, and the fibrillation behavior of the secondary filament within the jet flame stream was almost similar to that shown in FIG.

[Third example]

Using the glass T shown in FIG. 4 and having the pore diameter distribution shown in Table 7, glass fibers were produced under the same energy usage conditions as in Example 1 of the second example as follows. (1) Height from the center of the pores in the top row to the center of the pores in the bottom row of the peripheral wall 35 of the rotating body 34 shown in FIG. 6 is 30 mm (2) Number of pore rows is 30, total number of pores is 7710 ( 3) Glass T is supplied at 330 kg/h (4) Diameter of rotating body 34 is 300 mm (5) Thickness of peripheral wall 35 is as shown in Table 7, thinner in the upper region and thicker in the central region. (6) Set the pore diameter distribution as shown in Table 7 (7) Adjust the drawing burner 36 so that the average diameter of the glass fibers obtained is 7 microns. As a result, the temperature of each part of the peripheral wall 35 and the estimated temperature and viscosity of the molten glass passing through each pore were as shown in Table 7, and the standard deviation of the diameter distribution of the obtained glass fibers was 274 microns. The fibrillation behavior of the secondary filament within the jet flame stream 37 was as shown in FIG. 6, and almost no entanglement of glass fibers was observed.

[Table] In each of the above embodiments, when considering the temperature of the molten glass distributed inside the peripheral wall of the rotating body, the closer the temperature is to the devitrification temperature of the glass, the lower the temperature appears. In order to deal with this phenomenon, it is necessary to eliminate as much as possible the portion where the molten glass accumulates inside the rotating body.
As shown in Figures 5 and 6, a large number of molten glass discharge holes are drilled in the peripheral wall of the rotating body from a position touching the boundary between the inner surface of the bottom wall and the inner side of the peripheral wall, and the inside of the peripheral wall. By making the holes uniformly up to the point where they touch the boundary with the inner surface of the upper annular flange, the molten glass is discharged from the pores and finely divided without giving time for devitrification of the glass to occur. ing. In addition, when using molten glass whose viscosity changes rapidly as the temperature changes in the temperature-viscosity curve of the glass used, the thickness of the peripheral wall of the hollow cylindrical rotating body should be Using a rotating body in which the central region is thicker than the upper and lower regions, or the peripheral wall is thickest in the central region, thinnest in the upper region, and intermediate in the lower region, The pores are formed in the peripheral wall by selecting a diameter such that the diameter of the pore formed in the central region is smaller than the diameter of the pore formed in the upper region and the lower region, respectively. For example, it can be used with molten glass having the above characteristics. The present invention has the structure and operation described above, and can produce a larger amount of high-quality glass fiber or
The structure of the hollow cylindrical rotating body has the effect of producing high quality hard glass fibers without entanglement of glass fibers using glass harder than conventionally used glass as a raw material. By simply changing this, it is possible to produce high-quality glass fiber without increasing energy consumption or complicating equipment.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view of an example of a conventional glass fiber forming apparatus, FIG. 2 is a schematic enlarged sectional view of the main part of the apparatus shown in FIG. 1, and FIG. 3 is a first embodiment of the present invention. FIG. 4 is a diagram showing the relationship between glass temperature and viscosity. FIG. 5 is a schematic enlarged sectional view of the main parts of the second embodiment. FIG. 6 7 is a schematic enlarged sectional view of the main part of the third embodiment, and FIG. 7 is a schematic enlarged sectional view of the main part of the conventional device. 1: Rotating shaft, 2: Rotating body, 3: Bottom wall, 4: Pore, 5: Peripheral wall, 6: Upper annular flange, 7: Extension burner, 11: Crater, 12: Inner flame, 13: Outer flame, 14 : Injection flame stream, 15: Heating burner, 1
6: Flame.

Claims (1)

[Scope of Claims] 1. A hollow cylindrical rotating body having a bottom wall, a peripheral wall having a plurality of pores for discharging molten glass, and an upper annular flange located inside the upper end of the peripheral wall;
the elongated burner's nozzle for finely fibrillating the primary filament formed at the tip of the small glass cone discharged from the rotating body into a secondary filament; Only the outer flame portion of the flow whose velocity is attenuated to the extent that it does not destroy the small glass cone is disposed at a position where it contacts the lower part of the outer surface of the peripheral wall of the hollow cylindrical rotating body. A heating burner is attached to the inside of the upper annular flange of the hollow cylindrical rotating body, and the heating burner has a flame jet direction that is on the extended surface of the upper annular flange and is aligned with the surface of the upper annular flange. The heating degree is such that the flame passes through contact with the upper surface or the upper and lower surfaces of the upper annular flange, and the heat reaches at least the connection position between the annular flange and the peripheral wall of the hollow cylindrical rotating body. In a centrifugal glass fiber production device that is said to have a diameter of 100 to 300 mm, the diameter of the pores drilled in the central region of the peripheral wall is smaller than the diameter of the pores drilled in the upper and lower regions of the peripheral wall. A glass fiberizing device using a hollow cylindrical rotating body characterized by small diameter pores. 2. The hollow cylinder according to claim 1, wherein the central region of the peripheral wall of the hollow cylindrical rotating body is thicker than the thickness of the upper region and the lower region of the peripheral wall. A glass fiberizing device that uses a shaped rotating body. 3 The thickness of the circumferential wall of the hollow cylindrical rotating body is the thinnest in the upper region, the thickest in the central region, and the thickness in the lower region is intermediate between the upper region and the central region. A glass fiberizing apparatus using the hollow cylindrical rotating body described in 1. 4. The pores drilled in the peripheral wall of the hollow cylindrical rotating body extend from the position where the holes are in contact with the boundary between the inside of the bottom wall of the rotating body and the inside of the peripheral wall, and between the inside of the upper annular flange of the rotating body and the peripheral wall. A glass fiberizing apparatus using a hollow cylindrical rotating body according to claim 1, characterized in that the hollow cylindrical rotating body is formed up to a position where it contacts the boundary with the inside.