A continuous casting vibration coordinated feeding device and method for improving the quality of the casting

Abstract

A continuous casting vibration coordinated feeding device and method for improving the quality of ingots, belonging to the field of continuous casting production technology. The continuous casting vibration coordinated feeding device includes a plurality of feeding bins welded at intervals on the outside of a tundish, a feeding wheel is rotatably installed at the discharge port at the lower end of each feeding bin, the lower part of the discharge port is connected to the crystallizer through a feeding conduit, the driving end of the feeding wheel is connected to the vibration device through a connecting rod assembly, and the vibration device is connected to the crystallizer. The beneficial effect of the present invention is that the present invention can realize coordinated movement with the continuous casting crystallizer vibration device without the supply of an external power source, and the particulate materials such as crystallizer protective slag or liquid surface covering agent required in the continuous casting production process are evenly added to the crystallizer, thereby reducing production energy consumption, reducing the labor intensity of manual feeding, and improving the surface quality of the continuous casting ingot after casting.

Description

Technical Field

[0001] The invention relates to the technical field of continuous casting production, and in particular to a continuous casting vibration coordinated feeding device and method for improving the quality of casting blanks. Background Art

[0002] After the molten steel is poured by the continuous casting machine, it is necessary to continuously add protective slag or covering agent to the crystallizer during the continuous casting process. The protective slag or covering agent of the continuous casting crystallizer has five main functions in the continuous casting process: 1. Barrier function, which isolates the contact between air and molten steel, blocks the secondary oxidation of molten steel, blocks the contact between the carbon-rich layer and molten steel, avoids carbon increase on the surface of the ingot, improves the surface quality of the ingot, and reduces the loss of steel. 2. Insulation and heat preservation, which greatly improves the factory operating environment (heat radiation) and facilitates the smooth continuous casting. A sufficiently thick solid slag layer can better play the thermal insulation performance of the protective slag and prevent cold steel and floating steel from condensing on the surface of the crystallizer steel liquid. The increase in the temperature of the meniscus area of ​​the crystallizer will avoid many problems and accidents. Such as cracks, pores on the surface of the ingot, etc. 3. Absorption and dissolution of impurities, which can effectively absorb and dissolve impurities (system refractory materials, deoxidation products and other metal inclusions), and protect its own performance from changing, purify molten steel, and improve the purity of the surface of the ingot. 4. Lubrication function. The excellent lubrication function of protective slag can greatly reduce the friction between the ingot and the copper wall, thereby ensuring the smooth casting of the ingot and providing a guarantee for the continuous increase in the pulling speed. 5. Control and uniform heat transfer. The slag film cannot flow evenly between the copper wall and the ingot shell, which will cause uneven heat transfer. All cracks are caused by uneven heat transfer. For special steels such as peritectic steel, the heat transfer rate should be controlled to reduce the degree of peritectic reaction, otherwise serious cracks may occur on the surface of the ingot.

[0003] At present, most of the continuous casting machines of my country's steel enterprises adopt the production method of manually adding protective slag or covering agent, and some large state-owned enterprises also adopt automatic adding devices for protective slag or covering agent. However, long-term production practice shows that the granular materials such as protective slag or covering agent should be added frequently, in small amounts, and evenly, and the interval between each addition of granular materials should not be too long. The frequency and amount of adding protective slag or covering agent are also different when producing different steel grades.

[0004] Based on the above requirements and the influence of various changing factors, manual feeding obviously cannot meet the efficient production of modern high-quality, high-speed continuous casting; and the automatic feeding device is a batch production device based on the feeding mode, control method and other requirements set by the company in advance for the steel plant. Due to the limitations of the equipment itself, such as the feeding motor cannot achieve fast, trouble-free frequent reciprocating motion, once the material is blocked, it must be shut down for maintenance, and other inherent deficiencies of some mechanical equipment, it also cannot meet the trouble-free and adjustable mobility requirements of granular materials such as protective slag or covering agent. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a continuous casting vibration coordinated feeding device and method for improving the quality of the cast billet, which can realize coordinated movement with the continuous casting crystallizer vibration device without an external power source supply, and the particulate materials such as the crystallizer protective slag or liquid surface covering agent required in the continuous casting production process are evenly added to the crystallizer, thereby reducing production energy consumption, reducing the labor intensity of manual feeding, and improving the surface quality of the continuous casting billet after casting.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention to solve its technical problem is: the continuous casting vibration coordinated feeding device includes a plurality of feeding silos welded at intervals on the outside of the tundish, and a feeding wheel is rotatably installed at the discharge port at the lower end of each feeding silo. The lower part of the discharge port is connected to the crystallizer through a feeding conduit, and the driving end of the feeding wheel is connected to the vibration device through a connecting rod assembly, and the vibration device is connected to the crystallizer.

[0007] A rotating shaft is installed at the center of the feeding wheel, and one end of the rotating shaft passes through the feeding bin and is connected to the connecting rod assembly.

[0008] The feeding wheel comprises a mounting sleeve which is sleeve-fixedly connected with the rotating shaft, and the mounting sleeve is provided with a plurality of material-discharging blades at intervals along its circumference, and the corresponding material-discharging blades are sealed and connected with the discharge port when rotating to the lowermost end.

[0009] The connecting rod assembly includes a transmission guide rod connected to the vibration device, the upper end of the transmission guide rod is detachably connected to one end of a driving connecting rod through a connecting sleeve rod, and the other end of the driving connecting rod is connected to one end of the rotating shaft through a rotating rod to drive the feeding wheel to rotate.

[0010] The driving connecting rod comprises a straight rod portion connected to the transmission guide rod and a bent portion integrally connected thereto, and an end portion of the bent portion is rotatably connected to one end of the rotating rod.

[0011] The feeding conduit is configured as an inclined pipe, the outlet of the feeding conduit is located on the center line of the crystallizer, a flow control valve is installed on the feeding conduit, and the upper computer is connected to the flow control valve via a PLC; the center of the feeding bin coincides with the corresponding casting strand center line.

[0012] The vibration device is connected to the crystallizer through a vibration frame, and a positioning groove which is plug-connected with the bottom of the corresponding connecting rod assembly is provided on the vibration frame.

[0013] A continuous casting vibration coordinated feeding method, using the feeding device, comprises the following steps:

[0014] Step 1: Start the vibration device: according to the casting speed of the continuous casting machine required for the production of different types of steel continuous casting billets, the vibration device is vibrated at a certain frequency and amplitude;

[0015] Step 2: Install the feeding device: After the tundish is moved to the pouring position, install each connecting rod assembly on the vibration device;

[0016] Step 3: Add materials to the feeding device: Add materials to each feeding silo according to the set feeding frequency and addition amount.

[0017] The feeding frequency f in step 3 is related to the casting speed v of the continuous casting machine, and when producing high carbon steel, f=80v+20 times / min, when producing medium carbon steel, f=80v times / min, when producing low carbon steel, f=80v-20 times / min; the addition amount Q is determined according to the following formula: Moreover, the feeding frequency of each feeding bin is set to 5 to 15 seconds;

[0018] Where, Q is the specific amount of granular material added, g;

[0019] a, b are the length and width of the continuous casting billet, mm;

[0020] v is the casting speed of the continuous casting machine during normal production, m / min;

[0021] t is the vibration motion time, min;

[0022] ρ is the density of the granular material, which is 3.0-3.5 g / cm 3 .

[0023] The beneficial effects of the present invention are:

[0024] 1. The present invention ingeniously utilizes the vibration frequency motion of the crystallizer vibration device, and converts the up and down reciprocating motion of the crystallizer vibration device into the power for the rotation of the feeding wheel in the feeding device through the connecting rod assembly. Moreover, since the feeding bin is welded to the outside of the tundish, the granular materials such as the crystallizer protection slag or the liquid surface covering agent can be added while being baked, which can eliminate or reduce the baking energy consumption of the granular materials such as the crystallizer protection slag or the liquid surface covering agent before use. As the feeding wheel rotates, the granular materials in the feeding bin are continuously transported to the continuous casting crystallizer through the feeding conduit at the bottom of the feeding bin, which greatly reduces the labor intensity of manually adding the granular materials to the crystallizer and overcomes the mechanical failure and unchangeability caused by the electric feeding device.

[0025] 2. Since the vibration frequency and amplitude of the crystallizer vibration device are different during the production of different steel grades, the frequency and demand for adding granular materials such as protective slag or liquid surface covering agent are also different. Through the coordinated movement of the feeding device and the crystallizer vibration device, the structure of the feeding wheel in the designed feeding bin and the matching of the feeding blades in the feeding wheel and the discharge port, the production needs of different steel grades can be met. As the pouring proceeds, it is ensured that the granular materials such as protective slag or liquid surface covering agent are added evenly at a certain flow rate, so that the granular materials are evenly melted and spread from the center of the crystallizer to the surrounding areas, and cover the surface of the molten steel, which can greatly improve the surface cracks and pores of the continuous casting billet and improve the surface quality of the continuous casting billet after pouring. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The following is a brief description of the contents expressed in the drawings of the present specification and the marks in the drawings:

[0027] Figure 1 It is a front view of the continuous casting vibration coordinated feeding device of the present invention installed on the pouring equipment;

[0028] Figure 2 for Figure 1 Side view of

[0029] Figure 3 It is a structural schematic diagram of the continuous casting vibration coordinated feeding device of the present invention;

[0030] The marks in the above figures are: 1. Tundish, 2. Feeding silo, 3. Feeding wheel, 31. Rotating shaft, 32. Mounting sleeve, 33. Diverter blade, 4. Feeding conduit, 5. Crystallizer, 6. Connecting rod assembly, 61. Transmission guide rod, 62. Connecting sleeve rod, 63. Driving connecting rod, 631. Straight rod part, 632. Bending part, 64. Rotating rod, 7. Vibrating device, 8. Flow control valve. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0032] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The specific implementation scheme of the present invention is: Figure 1 to Figure 3 As shown, a continuous casting vibration coordinated feeding device for improving the quality of the ingot includes a plurality of feeding bins 2 welded at intervals on the outside of a tundish 1, Figure 1 It is a four-strand continuous casting machine. The number of feeding bins 2 is equal to the number of streams of the continuous casting machine. The feeding bins 2 are welded outside the tundish 1, so that granular materials such as crystallizer protective slag or liquid surface covering agent can be added while being baked, which can eliminate or reduce the energy consumption of baking granular materials such as crystallizer protective slag or liquid surface covering agent before use. A feeding wheel 3 is rotatably installed at the discharge port at the lower end of each feeding bin 2, and the lower part of the discharge port is connected to the crystallizer 5 through a feeding conduit 4. The driving end of the feeding wheel 3 is connected to the vibration device 7 through a connecting rod assembly 6, and the vibration device 7 is connected to the crystallizer 5. The vibration device 7 is an existing continuous casting machine crystallizer 5 vibration device 7. By utilizing the vibration frequency motion of the crystallizer 5 vibration device 7, the up and down reciprocating motion of the crystallizer 5 vibration device 7 is converted into the power for the rotation of the feeding wheel 3 in the feeding device through the connecting rod assembly 6. As the feeding wheel 3 rotates, the granular material in the feeding bin 2 is continuously transported to the continuous casting crystallizer 5 through the feeding conduit 4 at the lower part of the feeding bin 2, which greatly reduces the labor intensity of manually adding granular material to the crystallizer 5, overcomes the mechanical failure and unchangeability brought by the electric feeding device, ensures that the granular material is evenly added to the crystallizer 5 at a certain frequency, so that the granular material evenly covers the surface of the molten steel, greatly improves the surface cracks and pores of the continuous casting billet, and improves the surface quality of the continuous casting billet after casting.

[0035] Specifically, a rotating shaft 31 is installed at the center of the feeding wheel 3, and one end of the rotating shaft 31 passes through the feeding bin 2 and is connected to the connecting rod assembly 6, so that the up and down reciprocating vibration of the vibration device 7 can drive the rotating shaft 31 to rotate through the connecting rod assembly 6, thereby rotating the feeding wheel 3. The feeding wheel 3 includes a mounting sleeve 32 that is sleeved and fixedly connected to the rotating shaft 31, and the mounting sleeve 32 is provided with a plurality of material-dispensing blades 33 at intervals along its circumference. When the corresponding material-dispensing blade 33 rotates to the lowermost end, it is connected to the discharge port for sealing. With the up and down reciprocating vibration of the vibration device 7, the corresponding material-dispensing blade 33 rotates to the discharge port to achieve sealing and then detaches from the discharge port, so that the discharge port can be opened at a certain frequency, so that the granular material can be evenly put into the crystallizer 5 at a certain frequency.

[0036] The vibration device 7 is connected to the crystallizer 5 through a vibration frame. The crystallizer 5 can be vibrated reciprocatingly up and down through the vibration device 7, so that the crystallizer 5 can make an arc-like motion along the radius of the continuous casting machine according to a given amplitude, frequency and waveform deviation characteristics, making demoulding easier. A positioning groove connected to the bottom of the corresponding connecting rod assembly 6 is provided on the vibration frame, ensuring that the reciprocating vibration of the vibration device 7 can make the connecting rod assembly 6 move reciprocatingly up and down to rotate the feeding wheel 3 to realize automatic feeding. The connecting rod assembly 6 includes a transmission guide rod 61 connected to the vibration device 7. The upper end of the transmission guide rod 61 is detachably connected to one end of a driving connecting rod 63 through a connecting sleeve rod 62. After one pouring is completed and before the next pouring, the transmission guide rod 61 needs to be separated from the vibration device 7. The transmission guide rod 61 can be disassembled by disassembling the connecting sleeve rod 62. Before pouring, the transmission guide rod 61 can be connected to the driving connecting rod 63 through the connecting sleeve rod 62, so that the transmission guide rod 61 is connected to the vibration device 7, ensuring that the up and down reciprocating vibration of the vibration device 7 is transmitted upward through the transmission guide rod 61 to rotate the feeding wheel 3.

[0037] The driving connecting rod 63 includes a straight rod portion 631 connected to the transmission guide rod 61 and a bent portion 632 integrally connected thereto. The end of the bent portion 632 is rotatably connected to one end of the rotating rod 64. The driving connecting rod 63 moves up and down under the drive of the vibration device 7, so that the bent portion drives the rotating rod 64 to rotate, thereby driving the rotating shaft 31 to rotate, so that the feeding wheel 3 rotates synchronously, and the discharge port opens at a certain frequency to discharge materials.

[0038] The feeding conduit 4 is configured as an inclined pipe, and the outlet of the feeding conduit 4 is located on the center line of the crystallizer 5. The center of the feeding bin 2 coincides with the corresponding casting strand center line, so that granular materials such as crystallizer protective slag or liquid surface covering agent are first added from the center position of the crystallizer 5, and then melted and dispersed evenly around and cover the entire molten steel surface, ensuring that the granular materials evenly cover the molten steel surface.

[0039] In addition, a flow regulating valve 8 is installed on the feeding conduit 4. The upper computer is connected to the flow control valve 8 through the PLC. The flow of granular materials such as crystallizer protective slag or liquid surface covering agent can be adjusted according to different steel grades, so that the granular materials can be evenly fed into the crystallizer 5 at a certain frequency and flow rate.

[0040] A continuous casting vibration coordinated feeding method using a feeding device to improve the quality of the ingot includes the following steps:

[0041] Step 1: Start the vibration device 7: According to the pulling speed of the continuous casting machine required for the production of continuous casting billets of different steel grades, the vibration device 7 is vibrated at a certain frequency and amplitude, wherein the relationship between the pulling speed v and the frequency f is: when producing high carbon steel, f=80v+20 times / min, when producing medium carbon steel, f=80v times / min, when producing low carbon steel, f=80v-20 times / min.

[0042] Step 2: Install the feeding device: After the tundish 1 is moved to the pouring position, install each connecting rod assembly 6 on the vibration device 7; that is, the lower end of the driving connecting rod 63 is connected to the transmission guide rod 61 through the connecting sleeve rod 62, so that the transmission guide rod 61 is connected to the positioning groove on the vibration frame by snap-fitting.

[0043] Step 3: Adding materials to the feeding device: feeding materials into each feeding bin 2 according to the set feeding frequency and addition amount; the feeding frequency f is related to the casting speed v of the continuous casting machine, and when producing high carbon steel, f = 80v + 20 times / min, when producing medium carbon steel, f = 80v times / min, when producing low carbon steel, f = 80v-20 times / min; the addition amount Q is determined according to the following formula: Moreover, the feeding time of each feeding bin 2 is set to 5-15s per frequency, which can ensure the metallurgical effect of the granular material;

[0044] Where, Q is the specific amount of granular material added, g;

[0045] a, b are the length and width of the continuous casting billet, mm;

[0046] v is the casting speed of the continuous casting machine during normal production, m / min;

[0047] t is the vibration motion time, min;

[0048] ρ is the density of the granular material, which is 3.0-3.5 g / cm 3 .

[0049] The parameter values ​​of a, b, v, and ρ can be input to the PLC through the host computer. The formula enables PLC to automatically calculate the amount of particulate material added per minute. PLC controls the opening of the flow control valve 8 to meet the flow requirement, so that the particulate material is evenly fed into the crystallizer 5 at a certain frequency and flow rate, which can effectively improve the quality of the ingot.

[0050] Example 1

[0051] Taking the continuous casting production of rectangular high carbon steel continuous casting billet (steel grade is 82B, length a of continuous casting billet is 380mm, width b is 260mm) as an example, the method of adding mold protection slag is specifically described. The density of the mold protection slag is 3.2g / cm 3The casting speed of the continuous casting machine is 1.2m / min.

[0052] Step 1: Start the vibration device 7: according to the casting speed of the continuous casting machine for high carbon steel ingot production, the vibration device 7 is vibrated at a frequency of 116 times / min and an amplitude of ±4 mm;

[0053] Step 2: Install the feeding device: After the tundish 1 moves to the pouring position, the lower end of the driving connecting rod 63 is connected to the transmission guide rod 61 through the connecting sleeve rod 62, so that the transmission guide rod 61 is connected to the positioning groove on the vibration frame by clamping, so as to realize the connection between the feeding device and the vibration device 7, so that the vibration device 7 vibrates up and down once, and the feeding wheel 3 is rotated to a specific angle and then reset to realize the opening of the discharge port once, so that the rotation of the feeding wheel 3 and the vibration device 7 are synchronized. The feeding frequency of each flow feeding device is 116 times / min, and the feeding time of each feeding bin 2 per frequency is 10s;

[0054] Step 3: Add material to the feeding device: PLC controls the opening of the flow regulating valve 8 so that the flow rate of the mold protection slag from each feeding silo 2 to the crystallizer 5 is 379.4g / min, and the mold protection slag is first added from the center of the crystallizer 5, and then melted and spread evenly around and covers the entire steel liquid surface.

[0055] After the continuous casting of the above-mentioned high carbon steel continuous casting billet is completed, the continuous casting billet is sampled, cut and displayed in accordance with the provisions of GB / T 226, and the macrostructure and defects displayed in the cut are evaluated in accordance with YB / T 4002-2013 "Continuous Cast Steel Square Billet Macrostructure Defect Rating Chart", and the evaluation results are as follows: the center segregation grade of the continuous casting billet is 1.0, the center shrinkage grade is 0.5, the surface crack grade is 0.5; the corner crack grade is 0.

[0056] Example 2

[0057] Taking the continuous casting production of medium carbon steel continuous casting billet (steel grade is Q345B, the length a of the continuous casting billet is 165mm, the width b is 165mm) as an example, the method of adding mold protection slag is specifically described. The density of the mold protection slag is 3.35g / cm 3 The casting speed of the continuous casting machine is 3.0m / min.

[0058] Step 1: Start the vibration device 7: according to the casting speed of the continuous casting machine for producing medium carbon steel ingots, the vibration device 7 is vibrated at a frequency of 240 times / min and an amplitude of ±5 mm;

[0059] Step 2: Install the feeding device: After the tundish 1 moves to the pouring position, connect the lower end of the driving connecting rod 63 to the transmission guide rod 61 through the connecting sleeve rod 62, so that the transmission guide rod 61 is connected to the positioning groove on the vibration frame by clamping, so as to realize the connection between the feeding device and the vibration device 7, so that the vibration device 7 vibrates up and down once, and the feeding wheel 3 is rotated to a specific angle and then reset to realize the opening of the discharge port once, so that the rotation of the feeding wheel 3 and the vibration device 7 are synchronized, the feeding frequency of each flow feeding device is 240 times / min, and the feeding time of each feeding bin 2 per frequency is 15s;

[0060] Step 3: Add material into the feeding device: PLC controls the opening of the flow regulating valve 8 so that the flow rate of the mold protection slag from each feeding silo 2 to the crystallizer 5 is 273.6g / min, and the mold protection slag is first added from the center of the crystallizer 5, and then melted and spread evenly around and covers the entire steel liquid surface.

[0061] After the continuous casting of the above-mentioned medium carbon steel continuous casting billet is completed, the continuous casting billet is sampled, cut and displayed in accordance with the provisions of GB / T 226, and the macrostructure and defects displayed in the cut are evaluated in accordance with YB / T 4002-2013 "Continuous Cast Steel Square Billet Macrostructure Defect Rating Chart", and the evaluation results are as follows: the center crack grade of the continuous casting billet is 1.0, the center shrinkage grade is 1.0, the surface crack grade is 0.5, and the corner crack grade is 0.

[0062] Example 3

[0063] Taking the continuous casting production of low-carbon steel continuous casting slab (steel grade is C36-1, the length a of the continuous casting slab is 2050mm, and the width b is 230mm) as an example, the method of adding mold protection slag is specifically described. The density of the mold protection slag is 3.0g / cm 3 The casting speed of the continuous casting machine is 1.0m / min.

[0064] Step 1: Start the vibration device 7: according to the casting speed of the continuous casting machine for producing low-carbon steel ingots, the vibration device 7 is vibrated at a frequency of 60 times / min and an amplitude of ±3.5 mm;

[0065] Step 2: Install the feeding device: After the tundish 1 moves to the pouring position, connect the lower end of the driving connecting rod 63 to the transmission guide rod 61 through the connecting sleeve rod 62, so that the transmission guide rod 61 is connected to the positioning groove on the vibration frame by clamping, so as to realize the connection between the feeding device and the vibration device 7, so that the vibration device 7 vibrates up and down once, and the feeding wheel 3 is rotated to a specific angle and then reset to realize the opening of the discharge port once, so that the rotation of the feeding wheel 3 and the vibration device 7 are synchronized, the feeding frequency of each flow feeding device is 60 times / min, and the feeding time of each feeding bin 2 per frequency is 8s;

[0066] Step 3: Add material to the feeding device: PLC controls the opening of the flow regulating valve 8 so that the flow rate of the mold protective slag from each feeding silo 2 to the crystallizer 5 is 1414.5g / min, so that the granular material is first added from the center of the crystallizer 5, and then melted and spread evenly around and cover the entire steel liquid surface.

[0067] After the continuous casting of the above-mentioned low-carbon steel continuous casting billet is completed, the continuous casting billet is sampled, cut and displayed in accordance with the provisions of GB / T 226, and the macrostructure and defects displayed in the cut are evaluated in accordance with YB / T 4002-2013 "Continuous Cast Steel Square Billet Macrostructure Defect Rating Chart", and the evaluation results are as follows: the shrinkage grade of the continuous casting billet center is 0.5, the surface crack grade is 0.5, and the corner crack grade is 0.

[0068] Comparative Example 1

[0069] The difference from Example 1 is that the flow control valve 8 is not installed on the feeding conduit 4, so that the flow rate of the crystallizer protective slag from each feeding silo 2 to the crystallizer 5 is constant, which is 600g / min. The vibration device 7 vibrates up and down once, so that the feeding wheel 3 rotates a specific angle and then resets to realize the opening of the discharge port once, and the feeding amount each time is 200g.

[0070] After the continuous casting of the high carbon steel continuous casting billet is completed according to the above-mentioned feeding method, the evaluation results of the continuous casting quality of the continuous casting billet are as follows: the center segregation grade of the continuous casting billet is 1.5, the center shrinkage grade is 1.0, the surface crack grade is 1.0, and the corner crack grade is 1.0.

[0071] Due to excessive one-time feeding, the mold protection slag is seriously wasted, and a large amount of protection slag cannot be quickly melted in the crystallizer in a short time, resulting in serious quality defects such as slag curling, billet warping and nodules in the molten steel. It can be seen from the comparison between Example 1 and Comparative Example 1 that the flow rate of the mold protection slag has a great influence on the quality of the continuous casting billet, and the influence of various factors such as the length and width of the continuous casting billet, the pulling speed of the continuous casting machine and the vibration time of the crystallizer need to be comprehensively considered.

[0072] Comparative Example 2

[0073] The difference from Example 1 is that an automatic feeder is used to add protective slag to the crystallizer 5. The automatic feeder continuously adds protective slag to the crystallizer 5, and the flow rate of the protective slag is 500 to 1200 g / min.

[0074] After the continuous casting of the above-mentioned high carbon steel continuous casting billet is completed, the evaluation results of the continuous casting quality of the continuous casting billet are as follows: the center segregation grade of the continuous casting billet is 2.0, the center shrinkage grade is 1.5, the surface crack grade is 1.5, and the corner crack grade is 1.0.

[0075] Since the feeding flow rate of the automatic feeder is uncontrollable and is continuously added, the amount of slag cannot be adjusted according to the solidification characteristics of the steel grade, and a large amount of flow added is very likely to cause slag curling, nodules and surface cracks in the ingot. From the comparison of Example 2 and Comparative Example 1, it can be seen that continuously adding protective slag to the crystallizer will cause excessive addition of protective slag, while the addition of protective slag in each embodiment of the present invention is at the same frequency as the vibration device, achieving intermittent addition, which not only reduces energy consumption, but also allows the protective slag to be evenly dispersed and evenly covered on the surface of the molten steel, and improves the quality of the continuous casting ingot after continuous casting.

[0076] In summary, the present invention cleverly utilizes the vibration frequency motion of the crystallizer vibration device, and converts the up and down reciprocating motion of the crystallizer vibration device into the power for the rotation of the feeding wheel in the feeding device through the connecting rod assembly. As the feeding wheel rotates, the particulate material in the feeding bin is continuously transported to the continuous casting crystallizer through the feeding conduit at the bottom of the feeding bin, thereby overcoming the mechanical failure and immutability brought about by the electric feeding device, and can meet the production needs of different steel grades. As the pouring proceeds, it ensures that the particulate materials such as protective slag or liquid surface covering agent are evenly added at a certain flow rate, so that the particulate materials are evenly melted and spread from the center of the crystallizer to the surrounding areas, and cover the surface of the molten steel, which can greatly improve the surface cracks and pores of the continuous casting billet, and improve the surface quality of the continuous casting billet after pouring.

[0077] The above description is only used to illustrate some principles of the present invention. This specification is not intended to limit the present invention to the specific structure and application scope shown and described. Therefore, all corresponding modifications and equivalents that may be used belong to the patent scope applied for by the present invention.

Claims

1. A continuous casting vibration coordinated feeding method for improving the quality of the ingot, characterized in that: The following steps are involved: Step 1: Start the vibration device: according to the casting speed of the continuous casting machine required for the production of different types of steel continuous casting billets, the vibration device is vibrated at a certain frequency and amplitude; Step 2: Install a feeding device, which includes a plurality of feeding bins welded at intervals on the outside of the tundish, a feeding wheel is rotatably installed at the discharge port at the lower end of each feeding bin, the lower part of the discharge port is connected to the crystallizer through a feeding conduit, and the driving end of each feeding wheel is connected to a vibration device through a connecting rod assembly, and the vibration device is connected to the crystallizer: after the tundish moves to the pouring position, each connecting rod assembly is installed on the vibration device; Step 3: Add materials into the feeding device: Add materials into each feeding silo according to the set feeding frequency and addition amount; The feeding frequency f in step 3 is related to the casting speed v of the continuous casting machine, and when producing high carbon steel, f=80v+20 times / min, when producing medium carbon steel, f=80v times / min, when producing low carbon steel, f=80v-20 times / min; the addition amount Q is determined according to the following formula: Moreover, the feeding time of each feeding bin is set to 5 to 15 seconds per frequency; Where, Q is the specific amount of granular material added, g; a, b are the length and width of the continuous casting billet, mm; v is the casting speed of the continuous casting machine during normal production, m / min; t is the vibration motion time, min; ρ is the density of the granular material, which is 3.0-3.5 g / cm 3 .

2. The continuous casting vibration coordinated feeding method for improving the quality of the casting according to claim 1, characterized in that: A rotating shaft is installed at the center of the feeding wheel, and one end of the rotating shaft passes through the feeding bin and is connected to the connecting rod assembly.

3. The continuous casting vibration coordinated feeding method for improving the quality of the casting according to claim 2, characterized in that: The feeding wheel comprises a mounting sleeve which is sleeve-fixedly connected with the rotating shaft, and the mounting sleeve is provided with a plurality of material-discharging blades at intervals in the circumferential direction, and the corresponding material-discharging blades are sealed and connected with the discharge port when they rotate to the lowermost end.

4. The continuous casting vibration coordinated feeding method for improving the quality of the casting according to claim 2, characterized in that: The connecting rod assembly includes a transmission guide rod connected to the vibration device, the upper end of the transmission guide rod is detachably connected to one end of a driving connecting rod through a connecting sleeve rod, and the other end of the driving connecting rod is connected to one end of the rotating shaft through a rotating rod to drive the feeding wheel to rotate.

5. The continuous casting vibration coordinated feeding method for improving the quality of the casting according to claim 4, characterized in that: The driving connecting rod comprises a straight rod portion connected to the transmission guide rod and a bent portion integrally connected to the straight rod portion, and an end portion of the bent portion is rotatably connected to one end of the rotating rod.

6. The continuous casting vibration coordinated feeding method for improving the quality of the casting according to claim 1, characterized in that: The feeding conduit is configured as an inclined pipe, the outlet of the feeding conduit is located on the center line of the crystallizer, a flow control valve is installed on the feeding conduit, and the upper computer is connected to the flow control valve via a PLC; the center of the feeding bin coincides with the corresponding casting strand center line.

7. The continuous casting vibration coordinated feeding method for improving the quality of the casting according to claim 1, characterized in that: The vibration device is connected to the crystallizer through a vibration frame, and a positioning groove which is plug-connected with the bottom of the corresponding connecting rod assembly is provided on the vibration frame.

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