Ceramic composite long nozzle

Abstract

The utility model relates to the technical field of long nozzles, in particular to a ceramic composite long nozzle. The ceramic composite long nozzle comprises a pipe body and a heat insulation layer, and the heat insulation layer is arranged on the inner wall of the pipe body of the long nozzle. The gas guide block is arranged at the top of the pipe body, the outer diameter of the lower half part of the gas guide block is equal to that of the pipe body, the outer diameter of the upper half part of the gas guide block is slightly smaller than that of the lower half part, an annular groove is formed in the bottom of the gas guide block, the large diameter of the groove is equal to the inner diameter of the heat insulation layer, and a plurality of through holes are formed in the outer side wall of the upper half part of the gas guide block and connected with the groove; the sealing shell is arranged at the top of the air guide block and wraps the air guide block and the area from the top to the protruding part of the pipe body; and one end, which is not connected with the air inlet, of the air inlet pipe is connected with the high-pressure air pump capable of spraying air at a high speed. And a gas film is formed on the inner wall of the long nozzle to reduce the contact between the heat insulation layer and molten steel, so that the erosion and abrasion of the heat insulation layer are reduced, and the service life of the long nozzle is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to long water gap technical field especially relates to a ceramic composite long water gap. BACKGROUND

[0002] The ceramic composite long water gap (or called protection tube) is used between the ladle and the tundish to protect the molten steel from secondary oxidation and prevent the molten steel from splashing, and it is preheated before use, otherwise, cracking and fracture accidents may occur during pouring. At the initial stage of pouring, when the hot molten steel flows through the long water gap, a great thermal stress is generated inside the long water gap, which may cause cracking. Therefore, the long water gap must be preheated to above 1000 DEG C before use, which not only consumes energy and deteriorates the operating environment, but also causes complicated and time-consuming replacement operation. The development of the preheating-free long water gap is the key to solve the problem, and the manufacturing of the long water gap can be realized by two ways: one is to add graphite with high thermal conductivity and fused quartz with low thermal expansion rate, but this may reduce the corrosion resistance and erosion resistance of the long water gap; the other is to composite a heat insulation layer with low thermal conductivity in the inner hole of the long water gap, which is also the main development trend of the preheating-free long water gap. However, with the use of the long water gap, the heat insulation layer is gradually consumed, the heat insulation effect is deteriorated, and finally the long water gap may crack and fracture, which has a short service life.

[0003] Therefore, it is necessary to design a ceramic composite long water gap with a long service life. SUMMARY

[0004] In order to overcome the short service life of the heat insulation layer caused by the molten steel erosion, the technical problem is to provide a ceramic composite long water gap with a long service life.

[0005] A ceramic composite long water gap comprises a pipe body and a heat insulation layer, the inner wall of the long water gap pipe body is provided with the heat insulation layer, the upper half radius of the pipe body is constant, the lower half radius gradually decreases with the height, the pipe wall thickness is always constant, and a protrusion is arranged on the outer side of the pipe body near the top; a gas guide block is arranged on the top of the pipe body, the outer diameter of the lower half of the gas guide block is equal to the outer diameter of the pipe body, the outer diameter of the upper half of the gas guide block is slightly smaller than that of the lower half, an annular groove is arranged at the bottom of the gas guide block, the large diameter of the groove is equal to the inner diameter of the heat insulation layer, a plurality of through holes are arranged on the upper half of the outer side wall of the gas guide block and connected with the groove; a sealing shell is arranged on the top of the gas guide block to wrap the gas guide block and the top of the pipe body to the protrusion area; an air inlet is arranged at the same height as the upper half of the gas guide block on the outer side of the sealing shell; an air inlet pipe is connected to the air inlet; and a high-pressure gas pump is arranged at the end of the air inlet pipe which is not connected to the air inlet to enable high-speed ejection of gas.

[0006] Optionally, further comprising: a mounting column, the bottom of the pipe body is provided with a plurality of arc-shaped grooves, the distance between the sidewalls of the deep part of the grooves is greater than the distance between the sidewalls of the groove mouth, a mounting column that is matched with the shape of the groove is slidably arranged in each groove, and one end of each arc-shaped groove is provided with an opening through which the mounting column can freely enter and exit the groove; a horn cylinder, the bottom of the mounting column is provided with a horn cylinder, the outer diameter and the inner diameter of the top of the horn cylinder are equal to the pipe body, and the outer diameter and the inner diameter of the bottom of the horn cylinder are greater than the top of the horn cylinder; and a ventilation cylinder, the top of the horn cylinder is provided with a ventilation cylinder, and the outer diameter and the inner diameter of the top of the ventilation cylinder are equal to the heat insulation layer, and the sidewall of the heat insulation layer is provided with a plurality of ventilation holes.

[0007] Optionally, further comprising: an air heater, the air inlet of the high-pressure air pump is connected with an air heater capable of increasing the temperature of air.

[0008] Optionally, further comprising: the heat insulation layer material is a dense ceramic preform mainly made of corundum.

[0009] Optionally, further comprising: a heat preservation layer, a heat preservation layer capable of reducing the outflow of heat in the long nozzle is arranged between the pipe body and the heat insulation layer.

[0010] The beneficial effects of the utility model are: 1. a gas film is formed on the inner wall of the long nozzle, the contact between the heat insulation layer and molten steel is reduced, the erosion and wear of the heat insulation layer are reduced, and the service life of the long nozzle is improved.

[0011] 2. inert gas diffuses to the sidewall of the horn cylinder through the ventilation holes in the side of the ventilation cylinder, the passing area of the inert gas is increased, the gas speed is reduced, the purpose of preventing molten steel from splashing is achieved, and the mounting column and other components can make the replacement and installation process more convenient.

[0012] 3. the specially-made heat insulation layer material has better heat insulation, erosion resistance and corrosion resistance, thereby reducing the melting loss of the inner wall of the long nozzle and prolonging the service life. ACCURACY

[0013] Figure 1 It is a three-dimensional structure schematic view of the utility model.

[0014] Figure 2 It is a partial three-dimensional structure sectional view schematic view of the air guide block and the sealing shell and other components of the utility model.

[0015] Figure 3 It is a partial three-dimensional structure sectional view schematic view of the horn cylinder and the ventilation cylinder and other components of the utility model.

[0016] Figure 4 It is an explosion view of the mounting column and the pipe body of the utility model.

[0017] Marked in the drawing: 1: pipe body, 2: heat insulation layer, 3: air guide block, 4: sealing shell, 5: air inlet, 6: air inlet pipe, 7: high-pressure air pump, 8: mounting column, 9: horn cylinder, 10: air cylinder, 11: heat preservation layer, 12: air heater. DETAILED DESCRIPTION

[0018] The embodiments of the utility model are described below with reference to the drawings. EMBODIMENT

[0019] As Figures 1 to 3 shown, the utility model provides a kind of ceramic composite long nozzle, specifically including pipe body 1, heat insulation layer 2, air guide block 3, sealing shell 4, air inlet 5, air inlet pipe 6 and high-pressure air pump 7;

[0020] Among them, long nozzle pipe body 1 inner wall is equipped with heat insulation layer 2, upper half radius of pipe body 1 is invariable, lower half radius gradually decreases with height, pipe wall thickness is always invariable, the protrusion is equipped with on the outer side of pipe body 1 close to top position, for guiding flow to liquid steel;

[0021] Among them, pipe body 1 top is equipped with air guide block 3, the outer diameter of lower half portion of air guide block 3 is equal to pipe body 1 outer diameter, the outer diameter of upper half portion of air guide block 3 is slightly smaller than lower half portion, air guide block 3 bottom is equipped with annular groove, large diameter of groove is equal to heat insulation layer 2 inner diameter, the upper half outer side wall of air guide block 3 is equipped with multiple through holes and is connected with groove, for guiding to air current;

[0022] Among them, air guide block 3 top is equipped with sealing shell 4 and is wrapped air guide block 3 and pipe body 1 top to protruding portion area, air inlet 5 is equipped with on the outer side of sealing shell 4 and air guide block 3 upper half portion equal height, air inlet 5 is connected with an air inlet pipe 6, the end of air inlet pipe 6 not being connected with air inlet 5 is connected with high-pressure air pump 7 capable of making gas high-speed ejection, for blowing into high-pressure gas to long nozzle pipe body 1.

[0023] Exemplarily, when using, inert gas is pressurized by high-pressure air pump 7, reaches the gap formed in sealing shell 4 and air guide block 3 upper layer after passing through air inlet pipe 6 and air inlet 5, when inert gas fills the gap, under the drive of pressure, will enter the annular groove at air guide block 3 bottom by the through hole of air guide block 3 side wall, since annular groove opening is downward, inert gas is finally high-speed ejected along heat insulation layer 2 inner wall, since pipe body 1 is thick on top and thin on bottom, high-speed inert gas ejected will form a layer of air film along heat insulation layer 2 inner wall, when liquid steel enters this long nozzle from top to bottom, all liquid steel about to contact heat insulation layer 2 will be washed away by high-speed air film, enters tundish along pipe bottom, so, a layer of air film is formed on the inner wall of long nozzle, reduces the contact of heat insulation layer 2 and liquid steel, can reduce the erosion and wear of heat insulation layer 2, improves the service life of long nozzle. EMBODIMENT

[0024] AsFigure 3 and Figure 4 As shown, based on Embodiment 1, it also includes a mounting post 8, a horn tube 9, and a vent tube 10. The bottom of the tube body 1 is provided with multiple arc-shaped grooves. The distance between the side walls at the depth of the groove is greater than the distance between the side walls at the opening of the groove. Each groove is provided with a mounting post 8 that fits the shape of the groove in a sliding manner. One end of each arc-shaped groove is provided with an opening that allows the mounting post 8 to freely enter and exit the groove. The bottom of the mounting post 8 is provided with a horn tube 9. The outer diameter and inner diameter of the top of the horn tube 9 are equal to those of the tube body 1. The outer diameter and inner diameter of the bottom of the horn tube 9 are greater than those of the top of the horn tube 9. The inner side of the top of the horn tube 9 is provided with a vent tube 10. The outer diameter and inner diameter of the top of the vent tube 10 are equal to those of the heat insulation layer 2. The side wall of the heat insulation layer 2 is provided with multiple vent holes.

[0025] Because high-speed gas is ejected from the bottom of this long nozzle, the high-speed airflow will cause the molten steel to splash everywhere. Therefore, a horn 9 and a vent 10 are provided at the bottom of the tube body 1. After the molten steel and high-speed inert gas in the tube flow out from the bottom of the tube body 1, the inert gas diffuses from the through hole on the side of the vent 10 to the side wall of the horn 9, which increases the passage area of ​​the inert gas and reduces the gas velocity, thereby preventing the molten steel from splashing. Since the vent 10 and the horn 9 need to be subjected to the scouring of molten steel, they need to be replaced and maintained regularly. Therefore, a structure is provided in which the mounting post 8 and the groove at the bottom of the tube body 1 form a structure. The mounting post 8 can be installed by simply inserting it into the opening at one end of the groove and then rotating it. Conversely, it can be removed by simply inserting it into the groove. This facilitates regular replacement and maintenance.

[0026] like Figure 4 As shown, based on Embodiment 1, it also includes an air heater 12, and the air inlet 5 of the high-pressure air pump 7 is connected to the air heater 12, which can raise the air temperature.

[0027] Since a large amount of inert gas comes into contact with molten steel, the heat of the molten steel will be transferred to the inert gas and carried away with it when it is discharged, thus affecting the quality of the steel. Therefore, before the inert gas is pressurized by the high-pressure air pump 7, an air heater 12 is installed to heat the inert gas before pressurization, which can prevent the loss of heat from the molten steel.

[0028] The heat insulation layer 2 is made of a dense ceramic preform with corundum as the main component.

[0029] The ceramic pipe preform is made of white corundum, alumina powder, mullite, binder and other materials, is extruded by a grinding tool, and is baked at a high temperature of 1500 DEG C or above to be made into a ceramic pipe, the prepared ceramic pipe is installed on a special metal mold, is externally sleeved with a rubber mold special for isostatic pressing, is filled with a conventional resin-bonded continuous casting functional material in the middle, is integrally formed through an isostatic pressing process, and is processed through the same process as a conventional product, is solidified at 250 DEG C, is peripherally processed, is baked at 950 DEG C, and is canned to be completed, and the heat insulation layer 2 made in this way can have better heat insulation, erosion resistance and corrosion resistance, thereby reducing the molten loss of the inner wall of the long nozzle and prolonging the service life.

[0030] As shown in Figure 2 Based on the embodiment 1, the heat preservation layer 11 is further included, and the heat preservation layer 11 is arranged between the pipe body 1 and the heat insulation layer 2 to reduce the heat overflow of the long nozzle.

[0031] The heat preservation layer 11 can avoid the heat overflow of the long nozzle, reduce the heat loss of the molten steel, and ensure the quality of the steel.

[0032] The above is only a specific implementation manner of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A ceramic composite shroud, characterized in that it comprises: a pipe body (1) and a heat insulation layer (2), the inner wall of the pipe body (1) being provided with the heat insulation layer (2); a gas guide block (3), the top of the pipe body (1) being provided with the gas guide block (3), the bottom of the gas guide block (3) being provided with an annular groove, the diameter of the groove being equal to the inner diameter of the heat insulation layer (2), the upper half of the outer side wall of the gas guide block (3) being provided with a plurality of through holes connected with the groove; a sealing shell (4), the top of the gas guide block (3) being provided with the sealing shell (4) wrapping the gas guide block (3) and the pipe body (1); an air inlet (5), the outer side of the sealing shell (4) being provided with the air inlet (5) at the same height as the upper half of the gas guide block (3); an air inlet pipe (6), the air inlet (5) being connected with the air inlet pipe (6); a high-pressure air pump (7), one end of the air inlet pipe (6) not connected with the air inlet (5) being connected with the high-pressure air pump (7) capable of making gas jet at high speed.

2. The ceramic composite shroud of claim 1 further comprising comprising: mounting columns (8), the bottom of the pipe body (1) being provided with a plurality of arc-shaped grooves, each groove being slidably provided with a mounting column (8); a horn cylinder (9), the bottom of the mounting column (8) being provided with the horn cylinder (9); an air cylinder (10), the top inner side of the horn cylinder (9) being provided with the air cylinder (10), the side wall of the heat insulation layer (2) being provided with a plurality of air holes.

3. A ceramic composite shroud according to claim 2, further characterized by comprising: an air heater (12), the air inlet (5) of the high-pressure air pump (7) being connected with the air heater (12) capable of increasing the temperature of air.

4. A ceramic composite shroud according to claim 3, further characterized by comprising: a heat preservation layer (11), a heat preservation layer (11) capable of reducing the outflow of heat in the shroud being provided between the pipe body (1) and the heat insulation layer (2).

5. A ceramic composite shroud according to claim 4, wherein The material of the heat insulation layer (2) is a dense ceramic preform mainly composed of corundum.

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