Apparatus and method for glass isopipe forming

Abstract

The application discloses a device and a method for glass leak forming. It belongs to the technical field of optical glass manufacturing. It mainly solves the problem of forming stripes in the forming of optical glass with small viscosity, easy crystallization, easy volatilization and long low-temperature material property. The main features are as follows: the device is assembled by wrapping ceramic fiber cotton outside a channel through which glass liquid flows, and the channel is formed by welding a flow-in pipe, a flow guide pipe, a flow guide inner pipe, a cooling ring, a flow-out pipe, multiple electrode pieces and multiple thermocouples. The upper end of the flow-in pipe is welded and connected with the bottom of a working pot of a kiln, and the lower end is welded and connected with one side of the upper part of the flow-out pipe. The flow guide pipe is coaxially inserted into the flow-out pipe. The bottom of the flow guide pipe is lower than the flow-out pipe, and the height difference can be adjusted. The flow-out pipe, the flow guide pipe and the flow-in pipe are welded with temperature control thermocouples and electrode pieces. The application is suitable for the drawing forming of optical glass with small viscosity, easy crystallization, easy volatilization and long low-temperature material property.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of optical glass manufacturing, and particularly relates to a glass leak forming device and method. BACKGROUND

[0002] Optical glass has high requirements on internal quality such as stripes, and with the development of optical glass products towards high refractive index and high dispersion, low refractive index and low dispersion, and low melting point, the internal quality requirements of the products are getting higher and higher. The characteristics of high refractive index and high dispersion, low refractive index and low dispersion, and low melting point of optical glass are small viscosity and easy crystallization, etc. Therefore, when the glass liquid is formed, defects such as component volatilization and crystallization are easy to occur, forming forming defects such as surface stripes and crystallization of glass strip, resulting in low yield of products, high processing cost, and even product scrap, etc. The traditional optical glass leak tube is a platinum tube with different diameters welded to form a flow channel for glass liquid, and the glass liquid is injected into the mold for forming and solidification by electrode heating. The design of this forming leak tube leads to high core temperature of the glass liquid and difficulty in temperature reduction, small forming viscosity, large impact of the glass liquid in the mold, serious turbulent flow, serious volatilization of glass components, and easy formation of various shapes of stripes. For new varieties of special optical glass, the traditional leak forming method cannot solve the defects such as stripes of glass strip. SUMMARY

[0003] The purpose of the present application is to solve the above problems, and provide a leak forming device and method suitable for solving the forming stripes of special optical glass.

[0004] The technical solution of the forming device of the present application is: a glass leak forming device, comprising an inflow pipe and an inflow pipe heating control assembly, an outflow pipe and an outflow pipe heating control assembly, ceramic fiber cotton outside the inflow pipe and the outflow pipe, and a mold, the upper end of the inflow pipe is welded and connected with the bottom of the working pot of the kiln, characterized in that: it further comprises a flow guide pipe and a flow guide pipe heating control assembly, a flow guide inner pipe, and a cooling ring; the flow guide pipe is a blind pipe with a closed bottom, which is installed in the outflow pipe; the outflow pipe comprises an upper pipe body matched with the flow guide pipe and a lower pipe body forming a liquid flow channel with the flow guide pipe; the cooling ring is installed outside the flow guide pipe at the upper end of the outflow pipe; the flow guide inner pipe is arranged in the flow guide pipe and is provided with a vent hole; the outflow of the inflow pipe is welded and connected with one side of the lower pipe body of the outflow pipe; the outflow pipe heating control assembly is composed of an outflow pipe upper pipe body heating control assembly and an outflow pipe lower pipe body heating control assembly.

[0005] In the technical solution of the forming device of the present application, the flow guide pipe is inserted into the outflow pipe coaxially.

[0006] The technical solution of the forming device of the present application comprises a flow guide pipe, an inflow pipe, a flow guide inner pipe, a cooling ring and an outflow pipe.

[0007] The technical solution of the forming device of the present application further comprises an adjusting mechanism for adjusting the height difference between the bottom end of the flow guide pipe and the bottom end of the outflow pipe.

[0008] The adjusting mechanism of the technical solution of the forming device of the present application is a mechanical adjusting mechanism, which comprises a fixed plate, a movable plate and an adjusting screw. The fixed plate is clamped and fixed with the outer side of the cooling ring of the outflow pipe, the movable plate is clamped and fixed with the outer side of the upper end of the flow guide pipe, and the adjusting screw is connected with the fixed plate and the movable plate. The up-and-down movement of the flow guide pipe can be adjusted by the adjusting screw, so as to adjust the height difference between the bottom end of the flow guide pipe and the bottom end of the outflow pipe.

[0009] The inflow pipe, the flow guide pipe, the flow guide inner pipe, the cooling ring and the outflow pipe of the technical solution of the forming device of the present application are made of precious metal or precious metal alloy.

[0010] The flow guide pipe and the outflow pipe of the technical solution of the forming device of the present application are made of precious metal alloy with small wetting angle.

[0011] The technical solution of the forming device comprises the following: an electrode sheet C is welded on the upper end of the flow guide pipe, an electrode sheet B is welded on the middle part of the flow guide inner pipe exposed from the flow guide pipe, a thermocouple C is welded on the inner wall of the bottom of the flow guide inner pipe, a thermocouple A is welded on the outer side of the upper part of the outflow pipe, a thermocouple B is welded on the outer side of the lower part of the outflow pipe, an electrode sheet E is welded on the joint of the upper and lower pipe bodies of the outflow pipe, an electrode sheet F is welded on the bottom of the outer side of the lower pipe body of the outflow pipe, a thermocouple D is welded on the outer wall of the inflow pipe, an electrode sheet A is welded on the upper side of the inflow pipe, and the electrode sheets and the thermocouples are made of noble metal or noble metal alloy; the flow guide pipe, the flow guide inner pipe, the electrode sheet B, the electrode sheet C and the thermocouple C are combined into one whole; the inflow pipe heating control assembly is composed of the electrode sheet A, the electrode sheet E and the thermocouple D, the temperature of the glass liquid in the inflow pipe is controlled by adjusting the electric power between the electrode sheet A and the electrode sheet E through the temperature control instrument, so as to control the viscosity of the glass liquid in the inflow pipe; the lower pipe body heating control assembly of the outflow pipe is composed of the electrode sheet E, the electrode sheet F and the thermocouple B, the temperature of the glass liquid on the inner side of the lower part of the outflow pipe is controlled by adjusting the electric power between the electrode sheet E and the electrode sheet F through the temperature control instrument, so as to control the viscosity of the glass liquid in the outflow pipe; the upper pipe body heating control assembly of the outflow pipe is composed of the electrode sheet E, the electrode sheet D and the thermocouple A, the temperature of the glass liquid in the upper part of the outflow pipe is controlled by adjusting the electric power between the electrode sheet E and the electrode sheet D through the temperature control instrument, so as to control the viscosity of the glass liquid in the upper part of the outflow pipe; the flow guide pipe heating control assembly is composed of the electrode sheet B, the electrode sheet C and the thermocouple C, the temperature of the glass liquid outside the flow guide pipe is controlled by adjusting the electric power between the electrode sheet B and the electrode sheet C through the temperature control instrument, so as to control the viscosity of the glass liquid outside the flow guide pipe; the upper end of the flow guide inner pipe is connected with the air pipe, and the air pipe, the inner cavity of the flow guide inner pipe, the air hole at the bottom of the flow guide inner pipe, the gas cooling channel between the flow guide pipe and the flow guide inner pipe form a whole.

[0012] The technical solution of the forming method comprises the following steps:

[0013] (1) raising the temperature of the inflow pipe, and making the glass liquid flow from the working crucible along the inner wall of the inflow pipe into the outflow pipe;

[0014] (2) raising the temperature of the outflow pipe, and making the glass liquid fill the upper and lower cavities of the outflow pipe;

[0015] (3) raising the temperature of the flow guide pipe, and continuously reducing the viscosity of the glass liquid in the inner cavity of the outflow pipe and making the glass liquid flow downward along the wall of the flow guide pipe;

[0016] (4) adjusting the coaxiality of the flow guide pipe and the outflow pipe, and making the glass liquid uniformly distribute and overflow along the flow guide pipe;

[0017] (5) adjusting the height difference between the flow guide pipe and the outflow pipe to a proper position;

[0018] (6) Lower the temperature of the cooling ring to solidify the glass liquid in the upper part of the outlet pipe to fix the height difference and coaxiality of the position of the flow guide pipe and the outlet pipe;

[0019] (7) Adjust the air flow at the opening of the upper end of the flow guide inner pipe to make the glass liquid viscosity of the expanded part of the flow guide pipe increase rapidly;

[0020] (8) Pull the glass liquid in the mold to form the required glass strip;

[0021] (9) Empty the gas cavity formed by the overflow of the glass liquid at the bottom of the flow guide pipe and the mold;

[0022] (10) Adjust the height of the mold to make the upper surface of the glass liquid strip and the lower end of the flow guide pipe to a suitable distance;

[0023] (11) Adjust the temperature of the inlet pipe to adjust the discharge amount of the glass liquid;

[0024] (12) Adjust the temperature of the outlet pipe, adjust the temperature of the flow guide pipe, and adjust the air flow of the flow guide inner pipe; by adjusting the three, the viscosity and flow state of the glass liquid at the expanded part of the flow guide pipe are controlled to achieve the best forming process.

[0025] The technical solution of the forming method of the present application includes the following steps:

[0026] (1) Connect the power supply between the electrode sheet A and the electrode sheet E, and heat to the required temperature to make the glass liquid flow from the bottom of the working crucible into the outlet pipe along the inlet pipe;

[0027] (2) Connect the power supply between the electrode sheet D (9) and the electrode sheet E (11), and heat to the required temperature to make the glass liquid fill the upper cavity of the outlet pipe; connect the power supply between the electrode sheet E and the electrode sheet F, and heat to the required temperature to make the glass liquid fill the lower cavity of the outlet pipe;

[0028] (3) Connect the power supply between the electrode sheet B and the electrode sheet C, and heat to the required temperature to make the glass liquid in the outlet pipe cavity smaller and flow downward along the flow guide pipe wall;

[0029] (4) Observe the thickness of the glass liquid around the flow guide pipe when overflowing, adjust the coaxiality of the flow guide pipe and the outlet pipe, and make the glass liquid evenly distributed and overflow along the flow guide pipe;

[0030] (5) According to the viscosity change of the glass liquid, adjust the height difference between the flow guide pipe and the outlet pipe to the appropriate position;

[0031] (6) Pass cooling liquid or cooling air in the cooling ring to solidify the glass liquid in the upper part of the outlet pipe to fix the position of the flow guide pipe and the outlet pipe without changing.

[0032] (7) The air pipe is connected to the opening on the upper end of the flow guide inner tube to blow or suck the cooling air, so as to adjust the viscosity of the glass liquid at the expanded part of the flow guide tube, and make the viscosity of the glass liquid increase rapidly;

[0033] (8) The glass liquid leaked into the mold is pulled out of the mold by the pulling device to form the required glass strip;

[0034] (9) The gas in the cavity formed by the overflow of the glass liquid at the bottom of the flow guide tube and the mold is exhausted;

[0035] (10) The height of the mold is adjusted to make the upper surface of the glass liquid strip and the lower end of the flow guide tube have a suitable spacing;

[0036] (11) The power between the electrode sheet A and the electrode sheet E is adjusted, and the discharge amount of the glass liquid is adjusted by controlling the temperature of the thermocouple D on the inflow pipe;

[0037] (12) The power between the electrode sheet E and the electrode sheet F is adjusted to adjust the temperature of the thermocouple B on the outflow pipe; the power between the electrode sheet B and the electrode sheet C is adjusted to adjust the temperature of the thermocouple C on the flow guide tube; and the air volume of the opening on the upper end of the flow guide inner tube is adjusted. Through the cooperation of the three, the viscosity and flow state of the glass liquid at the expanded part of the flow guide tube are adjusted to achieve the best forming process.

[0038] The beneficial effects of the present application are:

[0039] 1. The device of the present application increases the cooling area of the leaked glass liquid, thereby rapidly increasing the viscosity of the glass liquid and reducing the generation of convection stripes in the forming process of the glass liquid.

[0040] 2. The special shape of the leaked material pipe design increases the cooling rate of the glass liquid, which can quickly pass through the crystallization region of the easy-crystallizing glass, and reduce the generation of crystallization stripes in the forming process of the easy-crystallizing glass.

[0041] 3. The special shape of the leaked material pipe design forms cooling of the inner and outer two columns, thins the thickness of the glass liquid column, greatly improves the cooling efficiency of the glass liquid, reduces the volatilization of the easy-volatile glass, and can reduce the occurrence of the forming surface stripes.

[0042] 4. The height of the flow guide inner tube of the present application is adjustable, which increases the wide forming process and can meet the forming of different glass materials, and draw high-quality glass strip without internal and external stripes and crystallization.

[0043] The present application is suitable for the drawing and forming of optical glass with small viscosity, easy crystallization, easy volatilization, and low temperature material properties. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is a front view schematic diagram of the device of the present application.

[0045] Figure 2 is the assembly profile of the flow guide pipe and the flow guide inner pipe.

[0046] The figure is marked as: 1-electrode piece A; 2-inflow pipe; 3-ceramic fiber cotton; 4-flow guide pipe; 5-flow guide inner pipe; 6-cooling ring; 7-electrode piece B; 8-electrode piece C; 9-electrode piece D; 10-thermocouple A; 11-electrode piece E; 12-thermocouple B; 13-outflow pipe; 14-electrode piece F; 15-glass liquid; 16-mold; 17-thermocouple C; 18-thermocouple D. DETAILED DESCRIPTION

[0047] The application is further described below in combination with the drawings.

[0048] -As Figure 1 shown. An embodiment of the glass overflow forming device of the application has the structure comprising: multiple sets of electrode pieces, an inflow pipe 2, a flow guide pipe 4, a flow guide inner pipe 5, a cooling ring 6, an outflow pipe 13, multiple branches of welded thermocouples, and ceramic fiber cotton 3. The upper end of the inflow pipe 2 is welded and connected to the bottom of the working crucible of the kiln, and the lower end is welded and connected to one side of the upper part of the outflow pipe 13. The flow guide pipe 4 is inserted into the outflow pipe 13 coaxially and is sleeved, the bottom position of the flow guide pipe 4 is lower than that of the outflow pipe 13, and the height difference can be adjusted. The outflow pipe 13, the flow guide pipe 4, and the inflow pipe 2 are all welded with temperature control thermocouples and electrode pieces.

[0049] The flow guide pipe 4 is a thin-walled blind pipe with a closed and enlarged bottom end. The flow guide inner pipe 5 is completely welded and fixed coaxially with the flow guide pipe 4 at the bottom of the enlarged blind side. The flow guide inner pipe 5 is slightly longer than the flow guide pipe 4. The upper end of the flow guide pipe 4 is welded with an electrode piece C 8. The middle part of the exposed part of the flow guide inner pipe 5 from the flow guide pipe 4 is welded with an electrode piece B 7. The inner wall near the welding position of the flow guide inner pipe 5 and the flow guide pipe 4 and located at the enlarged part of the flow guide pipe 4 is welded with a thermocouple C 17. A large number of air holes are opened on the bottom end wall of the flow guide inner pipe 5. The upper end of the flow guide inner pipe 5 is connected with an air pipe. The flow guide pipe 4, the electrode piece B 7, the electrode piece C 8, and the thermocouple C 17 are combined as a whole and can be moved up and down to accurately adjust the height difference with the outlet of the outflow pipe 13. The adjusting mechanism includes a fixed plate, a movable plate, and an adjusting screw. The fixed plate is clamped and fixed with the cooling ring on the outer side of the outflow pipe 13. The movable plate is clamped and fixed with the outer side of the upper end of the flow guide pipe 4. The adjusting screw connects the fixed plate and the movable plate. The flow guide pipe 4 is adjusted to move up and down by the adjusting screw, and the height difference between the bottom end of the flow guide pipe 4 and the bottom end of the outflow pipe 13 is adjusted.

[0050] - the outflow pipe 13 is welded by two vertical thin-walled pipes of coaxial and same diameter, the upper part of which is small in diameter and the lower part of which is large in diameter, and the inner diameter of the upper part of the outflow pipe 13 is matched with the outer diameter of the flow guide pipe 4 to fix the coaxiality and the height difference, a cooling ring 6 is welded on the upper end of the upper part of the outflow pipe 13, a thermocouple A 10 is welded on the outer side of the upper part of the outflow pipe 13, a thermocouple B 12 is welded on the middle of the outer side of the lower part of the outflow pipe 13, an electrode sheet E 11 is welded at the joint of the upper and lower parts of the outflow pipe 13, an electrode sheet F 14 is welded on the outer side of the bottom of the lower part of the outflow pipe 13, and the welding position of the inflow pipe 2 and the outflow pipe 13 is on the upper side of the lower part of the outflow pipe 13. The outflow pipe 13 is wrapped with ceramic fiber cotton 3.

[0051] - the inflow pipe 2 is welded with a thermocouple D 18 on the outer wall, welded with an electrode sheet A 1 on the upper left side, and wrapped with ceramic fiber cotton 3 on the outer side, and the glass liquid 15 in the inflow pipe 2 can be heated by passing current between the electrode sheet A 1 and the electrode sheet E 11, and the controllable heating of the inflow pipe 2 can be realized by matching the thermocouple D 18.

[0052] The inflow pipe 2, the flow guide pipe 4, the flow guide inner pipe 5, the cooling ring 6, the outflow pipe 13, the electrode sheets, and the thermocouples are made of noble metal or noble metal alloy, and the flow guide pipe 4 and the outflow pipe 13 are preferably made of noble metal alloy with small wetting angle to ensure the flowability of the glass liquid 15.

[0053] The inflow pipe 2 is composed of the electrode sheet A 1, the electrode sheet E 11, and the thermocouple D 18 to form the inflow pipe heating control assembly, the temperature of the glass liquid 15 in the inflow pipe 2 is controlled by adjusting the electric power between the electrode sheet A 1 and the electrode sheet E 11 through the temperature control instrument, thereby controlling the viscosity of the glass liquid 15 in the inflow pipe 2 and the flow rate of the glass liquid.

[0054] The lower part of the outflow pipe 13 is composed of the electrode sheet E 11, the electrode sheet F 14, and the thermocouple B 12 to form the lower part of the outflow pipe heating control assembly, the temperature of the glass liquid 15 inside the lower part of the outflow pipe 13 is controlled by adjusting the electric power between the electrode sheet E 11 and the electrode sheet F 14 through the temperature control instrument, thereby controlling the viscosity of the glass liquid 15 in the outflow pipe 13; the upper part of the outflow pipe 13 is composed of the electrode sheet E 11, the electrode sheet D 9, and the thermocouple A 10 to form the upper part of the outflow pipe heating control assembly, the temperature of the glass liquid 15 in the upper part of the outflow pipe 13 is controlled by adjusting the electric power between the electrode sheet E 11 and the electrode sheet D 9 through the temperature control instrument, thereby controlling the viscosity of the glass liquid 15 in the upper part of the outflow pipe 13.

[0055] The draft tube 4 is composed of the electrode sheet B7, the electrode sheet C8 and the thermocouple C17 to form a draft tube heating control assembly. The temperature of the glass liquid 15 outside the draft tube 4 is controlled by adjusting the electric power between the electrode sheet B7 and the electrode sheet C8 through the temperature control instrument, so as to control the viscosity of the glass liquid 15 outside the draft tube 4. The upper end of the draft inner tube 5 is connected with the air pipe to form a gas cooling channel composed of the air pipe, the draft inner tube cavity, the small hole at the bottom of the draft tube, and the cavity between the draft tube and the draft inner tube.

[0056] The forming method of the leak injection device is as follows:

[0057] (1) The temperature of the inflow pipe 2 is raised, and the glass liquid 15 flows into the outflow pipe 13 along the inner wall of the inflow pipe 2 from the working crucible;

[0058] (2) The temperature of the outflow pipe 13 is raised, and the glass liquid 15 fills the upper and lower cavities of the outflow pipe 13;

[0059] (3) The temperature of the draft tube 4 is raised, and the viscosity of the glass liquid 15 in the cavity of the outflow pipe 13 continuously decreases and flows downward along the wall of the draft tube 4;

[0060] (4) The coaxiality of the draft tube 4 and the outflow pipe 13 is adjusted, so that the glass liquid 15 uniformly distributes and overflows along the draft tube 4;

[0061] (5) The height difference between the draft tube 2 and the outflow pipe 13 is adjusted to an appropriate position;

[0062] (6) The temperature of the cooling ring is lowered, so that the glass liquid 15 in the small-diameter upper part of the outflow pipe 13 solidifies, to fix the position height difference and the coaxiality of the draft tube 4 and the outflow pipe 13;

[0063] (7) The air volume at the opening of the upper end of the draft inner tube 5 is adjusted, so that the viscosity of the glass liquid 15 at the expanded part of the draft tube 4 rapidly increases;

[0064] (8) The glass liquid 15 in the mold 16 is pulled to form a glass strip as required;

[0065] (9) The gas in the cavity formed by the overflow of the glass liquid 15 at the bottom of the draft tube 4 and the mold 16 is exhausted;

[0066] (10) The height of the mold 16 is adjusted, so that the upper surface of the glass liquid 15 strip and the lower end of the draft tube 4 are at an appropriate distance;

[0067] (11) The temperature of the inflow pipe 2 is adjusted to adjust the discharge amount of the glass liquid 15;

[0068] (12) Adjusting the temperature of the outflow pipe 13, adjusting the temperature of the guide pipe 4, adjusting the ventilation of the guide inner pipe 5; through the cooperation among the three, the viscosity and flow state of the glass liquid 15 at the expanded part of the guide pipe 4 are controlled to achieve the best forming process.

[0069] The forming method of the leakage injection device is also provided with the following steps:

[0070] (1) The power supply is connected between the electrode sheet A1 and the electrode sheet E11, and the temperature is raised to the process requirement, so that the glass liquid 15 flows into the outflow pipe 13 from the bottom of the working crucible along the inflow pipe 2;

[0071] (2) The power supply is connected between the electrode sheet D9 and the electrode sheet E11, and the temperature is raised to the process requirement, so that the glass liquid 15 fills the upper cavity of the outflow pipe 13; the power supply is connected between the electrode sheet E11 and the electrode sheet F14, and the temperature is raised to the process requirement, so that the glass liquid 15 fills the lower cavity of the outflow pipe 13;

[0072] (3) The power supply is connected between the electrode sheet B7 and the electrode sheet C8, and the temperature is raised to the process requirement, so that the glass liquid 15 in the cavity of the outflow pipe 13 melts and flows downward along the wall of the guide pipe;

[0073] (4) The thickness of the glass liquid 15 around the guide pipe 4 is observed when it overflows, and the coaxiality of the guide pipe 4 and the outflow pipe 13 is adjusted, so that the glass liquid 15 is evenly distributed and overflows along the guide pipe 4;

[0074] (5) According to the viscosity change of the glass liquid, the height difference between the guide pipe 2 and the outflow pipe 13 is adjusted to an appropriate position;

[0075] (6) The cooling liquid or cooling air is passed through the cooling ring 6, so that the glass liquid in the small-diameter upper part of the outflow pipe 13 solidifies, to fix the position of the guide pipe 4 and the outflow pipe 13 and prevent them from changing;

[0076] (7) The cooling air is blown into (or sucked out of) the air pipe connected to the upper opening of the guide inner pipe 5, so that the viscosity of the glass liquid 15 at the expanded part of the guide pipe 4 is adjusted, and the viscosity of the glass liquid 15 is rapidly increased;

[0077] (8) The glass liquid 15 in the leakage injection mold 16 is pulled out of the mold by the traction equipment, and is formed into the required glass strip;

[0078] (9) The gas in the cavity formed by the overflow of the glass liquid 15 at the bottom of the guide pipe 4 and in the mold 16 is exhausted;

[0079] (10) The height of the mold 16 is adjusted, so that the upper surface of the glass liquid 15 strip and the lower end of the guide pipe 4 are at an appropriate distance;

[0080] (11) Adjusting the power between electrode sheet A1 and electrode sheet E11 to adjust the temperature of thermocouple D18 on inflow pipe 2 to adjust the outflow of glass liquid 15;

[0081] (12) Adjusting the power between electrode sheet E11 and electrode sheet F14 to adjust the temperature of thermocouple B12 on outflow pipe 13; adjusting the power between electrode sheet B7 and electrode sheet C8 to adjust the temperature of thermocouple C17 on inflow pipe 4; adjusting the air flow through the opening on the upper end of inflow inner pipe 5; through the cooperation of the three, the viscosity and flow state of glass liquid 15 at the expanded part of inflow pipe 4 are controlled to achieve the best forming process.

Claims

1. A glass casting apparatus for forming high-refractive-index, high-dispersion, low-refractive-index, low-dispersion, and low-melting-point optical glass strips, comprising an inflow pipe (2) and an inflow pipe heating control assembly, an outflow pipe (13) and an outflow pipe heating control assembly, ceramic fiber cotton (3) on the outside of the inflow pipe (2) and the outflow pipe (13), and a mold (16), wherein the upper end of the inflow pipe (2) is welded to the bottom of the working crucible of the kiln, characterized in that: It also includes a guide pipe (4) and a guide pipe heating control assembly, a guide inner pipe (5), a cooling ring (6) and an adjustment mechanism; the guide pipe (4) is a blind pipe with a closed bottom and is installed in the outflow pipe (13); the outflow pipe (13) includes an upper pipe body that cooperates with the guide pipe (4) and a lower pipe body that forms a liquid flow channel with the guide pipe (4); the cooling ring (6) is installed on the outside of the guide pipe (4) at the upper port of the outflow pipe (13); the guide inner pipe (5) is set inside the guide pipe (4) and is provided with a vent hole; the outlet port of the inflow pipe (2) is welded to one side of the lower pipe body of the outflow pipe (13); the outflow pipe heating control assembly is composed of an outflow pipe upper pipe body heating control assembly and an outflow pipe lower pipe body heating control assembly; the adjustment mechanism adjusts the height difference between the bottom end of the guide pipe (4) and the bottom end of the outflow pipe (13).

2. The apparatus for glass casting according to claim 1, characterized in that: The guide tube (4) is inserted into the outlet tube (13) and coaxially fitted, with the bottom of the guide tube (4) being lower than that of the outlet tube (13).

3. The apparatus for glass casting according to claim 2, characterized in that: The guide tube (4) is a thin-walled blind tube with a closed and enlarged bottom end. The inner guide tube (5) and the guide tube (4) are completely welded and coaxially fixed at the bottom of the enlarged blind side to form a whole. The inner guide tube (5) has a large number of small ventilation holes on the bottom wall. The upper end is higher than the upper end of the guide tube (4) and the outlet tube (13) and is connected to the ventilation pipeline. The upper tube body and the lower tube body of the outlet tube (13) are smoothly transitioned.

4. The apparatus for glass casting according to claim 1, 2 or 3, characterized in that: The adjustment mechanism is a mechanical adjustment mechanism, including a fixed plate, a movable plate and an adjustment screw; the fixed plate is clamped and fixed to the cooling ring on the outer side of the outflow pipe (13), the movable plate is clamped and fixed to the outer side of the upper end of the guide pipe (4), and the adjustment screw connects the fixed plate and the movable plate; the guide pipe (4) can be adjusted up and down by adjusting the screw to adjust the height difference between the bottom end of the guide pipe (4) and the bottom end of the outflow pipe (13).

5. The apparatus for glass casting according to claim 1, 2 or 3, characterized in that: The inflow pipe (2), the guide pipe (4), the inner guide pipe (5), the cooling ring (6), and the outflow pipe (13) are made of precious metals or precious metal alloys.

6. The apparatus for glass casting according to claim 5, characterized in that: The guide tube (4) and the outlet tube (13) are made of noble metal alloys with small wetting angles.

7. An apparatus for glass casting according to any one of claims 1-3 and 6, characterized in that: The upper end of the guide tube (4) is welded with an electrode plate C (8), the middle part of the inner guide tube (5) exposed from the guide tube (4) is welded with an electrode plate B (7), the inner wall of the bottom of the inner guide tube (5) is welded with a thermocouple C (17), the outer side of the upper part of the outlet tube (13) is welded with a thermocouple A (10), and the outer side of the lower part of the outlet tube (13) is welded with a thermocouple B (12). Electrode plate E (11) is welded at the junction of the upper and lower tube bodies of the outflow pipe (13). Electrode plate F (14) is welded to the outer side of the bottom of the lower tube body of the outflow pipe (13). Thermocouple D (18) is welded to the outer wall of the inflow pipe (2). Electrode plate A (1) is welded to the upper side of the inflow pipe (2). The electrode plates and thermocouples are made of precious metals or precious metal alloys. The guide pipe (4), the guide inner pipe (5), electrode plate B (7), electrode plate C (8), and thermocouple C (17) are combined into a whole. The heating control component of the inflow pipe is composed of electrode plate A (1). The outlet pipe consists of electrode plate E (11), thermocouple D (18), and the temperature of the glass melt (15) flowing into the pipe (2) is controlled by adjusting the electrical power between electrode plate A (1) and electrode plate E (11) through a temperature controller, thereby controlling the viscosity of the glass melt (15) flowing into the pipe (2); the outlet pipe lower tube body heating control assembly consists of electrode plate E (11), electrode plate F (14), thermocouple B (12), and the temperature of the outlet pipe (13) is controlled by adjusting the electrical power between electrode plate E (11) and electrode plate F (14) through a temperature controller. The temperature of the glass melt (15) on the inner side of the lower part is controlled to regulate the viscosity of the glass melt (15) in the outflow pipe (13); the heating control assembly of the upper part of the outflow pipe consists of electrode plate E (11), electrode plate D (9), and thermocouple A (10). The temperature of the glass melt (15) in the upper part of the outflow pipe (13) is controlled by adjusting the electrical power between electrode plate E (11) and electrode plate D (9) through a temperature controller, thereby controlling the viscosity of the glass melt (15) in the upper part of the outflow pipe (13); the heating control assembly of the guide pipe consists of an electric... The heating control assembly consists of electrode B (7), electrode C (8), and thermocouple C (17). The temperature of the glass melt (15) outside the guide tube (4) is controlled by adjusting the electrical power between electrode B (7) and electrode C (8) through a temperature control instrument, thereby controlling the viscosity of the glass melt (15) outside the guide tube (4). The upper opening of the inner guide tube (5) is connected to a vent pipe, forming a gas cooling channel consisting of a vent pipe, the inner cavity of the inner guide tube (5), a small vent hole at the bottom of the inner guide tube (5), and the chamber between the guide tube (4) and the inner guide tube (5).

8. A method for glass casting using the glass casting apparatus of claim 7, for forming high-refractive-index high-dispersion, low-refractive-index low-dispersion, and low-melting-point optical glass strips, characterized in that... Includes the following steps: (1) Increase the temperature of the inflow pipe (2) and let the glass liquid (15) flow from the working crucible along the inner wall of the inflow pipe (2) into the outflow pipe (13); (2) Increase the temperature of the outflow tube (13) to allow the glass melt (15) to fill the upper and lower chambers of the outflow tube (13); (3) Increase the temperature of the guide tube (4) so ​​that the viscosity of the glass melt (15) in the inner cavity of the outflow tube (13) continues to decrease and flows downward along the wall of the guide tube (4); (4) Adjust the coaxiality of the guide tube (4) and the outlet tube (13) so that the glass liquid (15) is evenly distributed and overflows along the guide tube (4); (5) Adjust the height difference between the guide tube (4) and the outlet tube (13) to a suitable position; (6) Reduce the temperature of the cooling ring to solidify the glass liquid (15) in the upper part of the small diameter of the outflow pipe (13) to fix the position height difference and coaxiality of the guide pipe (4) and the outflow pipe (13); (7) Adjust the air flow at the upper opening of the inner guide tube (5) to make the viscosity of the glass melt (15) at the expansion of the guide tube (4) increase rapidly; (8) Pull the molten glass (15) in the mold (16) to form the required glass strip; (9) The bottom of the drain pipe (4) and the glass liquid (15) inside the mold (16) may overflow and form a cavity; (10) Adjust the height of the mold (16) so that the upper surface of the glass melt (15) strip is at a suitable distance from the lower end of the guide tube (4); (11) Adjust the temperature of the inflow pipe (2) to adjust the discharge rate of the glass melt (15); (12) Adjust the temperature of the outflow pipe (13), adjust the temperature of the guide pipe (4), and adjust the air flow of the inner guide pipe (5); through the coordination and adjustment of the three, control the viscosity and flow state of the glass liquid (15) at the expansion point of the guide pipe (4) to achieve the best forming process.

9. The method for glass casting according to claim 8, characterized in that... Includes the following steps: (1) Connect a power source between electrode A (1) and electrode E (11), and heat the glass liquid (15) to the required temperature, so that the glass liquid (15) flows from the bottom of the working crucible into the outflow pipe (13) along the inflow pipe (2); (2) Connect a power source between electrode plate D (9) and electrode plate E (11), and heat the glass liquid (15) to the required temperature to fill the upper cavity of the outlet tube (13); connect a power source between electrode plate E (11) and electrode plate F (14), and heat the glass liquid (15) to the required temperature to fill the lower cavity of the outlet tube (13); (3) Connect a power source between electrode plate B (7) and electrode plate C (8), and heat the glass melt (15) in the inner cavity of the outflow tube (13) to reduce the viscosity and flow downward along the wall of the guide tube. (4) Observe the thickness of the glass liquid (15) around the guide tube (4) when it overflows, and adjust the coaxiality of the guide tube (4) and the outlet tube (13) so that the glass liquid (15) overflows evenly along the guide tube (4); (5) Adjust the height difference between the guide tube (4) and the outlet tube (13) to a suitable position according to the viscosity change of the glass melt; (6) Cooling liquid or cooling air is introduced into the cooling ring to solidify the glass liquid in the upper part of the small diameter of the outflow pipe (13) so as to fix the position of the guide pipe (4) and the outflow pipe (13) so that they do not change. (7) Connect the upper opening of the guide tube (5) to the ventilation tube to blow in or draw out cooling air, and adjust the viscosity of the glass liquid (15) at the expansion of the guide tube (4) so ​​that the viscosity of the glass liquid (15) increases rapidly. (8) Use a traction device to pull the molten glass (15) that has leaked into the mold (16) out of the mold and form it into the required glass strip; (9) The bottom of the drain pipe (4) and the glass liquid (15) inside the mold (16) may overflow and form a cavity; (10) Adjust the height of the mold (16) so that the upper surface of the glass melt (15) strip is at a suitable distance from the lower end of the guide tube (4); (11) Adjust the power between electrode A (1) and electrode E (11), and adjust the output of glass melt (15) by controlling the temperature of thermocouple D (18) on inlet pipe (2); (12) Adjust the power between electrode plate E (11) and electrode plate F (14) to adjust the temperature of thermocouple B (12) on the outflow pipe (13); adjust the power between electrode plate B (7) and electrode plate C (8) to adjust the temperature of thermocouple C (17) on the guide pipe (4); adjust the air flow rate at the upper opening of the guide inner pipe (5). By coordinating the three, control the viscosity and flow state of the glass liquid (15) at the expansion point of the guide pipe (4) to achieve the best forming process.

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