Pilot test furnace and test method for anti-burst performance of refractory castables

Abstract

The present invention provides a pilot test furnace for anti-burst performance of refractory castables and a test method thereof. The pilot test furnace comprises: a furnace body, which is used to provide a baking space for a test castable, wherein the thickness of the test castable is consistent with the thickness of the castable product in the actual production process; a furnace cover, which is installed on the top of the furnace body; and a heat storage combustion system, which is arranged on the furnace cover and is used to bake the test castable by burning coal gas / natural gas. The pilot test furnace is basically consistent with the baking environment and conditions on site, including that the baking energy medium is coal gas or natural gas, the degree of simulation on site is high, and the evaluation accuracy of the anti-burst performance of refractory castables is very high, which is conducive to the research and application of refractory castables.

Description

Technical Field

[0001] The invention relates to the technical field of refractory materials, in particular to a pilot test furnace for anti-burst performance of refractory castables and a test method thereof. Background Art

[0002] Ladles and iron ladles are important thermal vessels in the steelmaking process, and their linings are made of refractory materials. With the continuous improvement of the requirements for clean steel smelting, the proportion of castables used in the linings of ladles and iron ladles is increasing, especially at the bottom of the ladle. After these refractory castables are cast, they must be baked before they can be used. However, in order to increase the service life of the castable, refractory material workers add micropowder or ultra-micropowder to it. The addition of micropowder increases the density of the castable and blocks the exhaust channel, making it difficult for water vapor to be discharged during the heating and baking process of the castable, which eventually leads to the explosion of the refractory castable during the baking process. After the explosion, the castable will be dismantled or repaired, and the use effect is extremely poor, which is difficult to meet the use requirements.

[0003] At present, when studying this type of castable, the quality of the anti-bursting performance of the castable is measured by a small test furnace, which is an electric furnace, such as the two refractory castable bursting test furnaces published by the utility model patent (ZL201620004107.1) and the utility model patent (ZL201822093827.8). This type of method cannot truly evaluate the anti-bursting performance of the castable, and its evaluation accuracy is low, which makes it difficult to prevent the castable from baking and bursting in the steel plant. The main reasons are: 1) The volume of the sample is very different from the volume of the castable in the actual ladle or iron ladle, and the internal vapor pressure is very different; 2) The test furnace uses electric baking, while steel plants basically use coal gas (or natural gas) for baking, and different baking methods will cause large differences in exhaust speed. Summary of the invention

[0004] In order to solve the problems of low accuracy and low efficiency in the current test equipment and methods for evaluating the anti-bursting performance of refractory castables for steel ladles, the object of the present invention is to provide a pilot test furnace for the anti-bursting performance of refractory castables and a test method thereof.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A pilot test furnace for anti-burst performance of refractory castables, comprising:

[0007] A furnace body, used to provide a baking space for the test casting, wherein the thickness of the test casting is consistent with the thickness of the casting product in the actual production process;

[0008] Furnace cover, installed on the top of the furnace body;

[0009] The heat storage combustion system is arranged on the furnace cover and connected to the furnace body, and is used to bake the test casting body through the combustion of coal gas / natural gas.

[0010] Preferably, the furnace body is overhead, and the bottom of the furnace body is open; the furnace body includes a wall and a furnace shell wrapped outside the wall; the wall is made of refractory bricks; the maximum use temperature of the refractory bricks is ≥1600°C, and the volume density is 2.5-3.0g / cm 3 , thermal conductivity ≤2.0W / m·K.

[0011] Preferably, it also includes an automatic lifting system, which is arranged below the furnace body and is used for lifting the test casting body and then allowing it to enter through the bottom opening of the furnace body and be installed in the furnace body.

[0012] Preferably, the furnace cover is made of steel material, and the lower part of the furnace cover is covered with a refractory material with a heat-insulating function; the maximum operating temperature of the refractory material is ≥1400°C.

[0013] Preferably, the thermal storage combustion system is provided with an air pipeline and a gas pipeline for conveying air and gas / natural gas to the thermal storage combustion system for combustion, thereby baking the test casting.

[0014] Preferably, it also includes a temperature monitoring device, which is installed on the furnace cover and uses an infrared temperature measurement method to monitor the internal temperature of the furnace body.

[0015] Preferably, it also includes a transmission system, which is arranged outside the furnace body and connected to the automatic lifting system, and is used to transmit the test casting body to the automatic lifting system below the furnace body.

[0016] Preferably, it also includes a casting mold for pouring the casting material for shaping to obtain a test casting body; the thickness of the test casting body is consistent with the thickness of the casting body product in the actual production process; the casting mold is provided with a mold partition for separating the internal space of the casting mold; the bottom of the casting mold is provided with a mold support plate, and the size of the mold support plate is larger than the bottom opening of the furnace body; after the automatic lifting system lifts the test casting body together with the casting mold, the test casting body is transported into the furnace body through the bottom opening of the furnace body, and the mold support plate seals the bottom opening of the furnace body.

[0017] Preferably, the casting mold, mold partition and mold support plate are made of steel material, and the maximum operating temperature of the steel material of the casting mold and mold partition is ≥1500°C; the maximum operating temperature of the steel material of the mold support plate is ≥500°C, and the tensile strength is ≥500MPa.

[0018] Preferably, it also includes a rotating device; the rotating device includes a connecting mechanism, a movable pulley group and a fixed pulley group; the connecting mechanism and the fixed pulley group are connected via the movable pulley group, and under the action of the movable pulley group and the fixed pulley group, the rotating device can be opened, closed, and the height of the furnace cover can be adjusted.

[0019] Preferably, it also includes a computer remote control system, which is arranged in the operation room and is used to set, start and end the baking system program; the computer remote control system collects temperature data sent by the temperature monitoring device, and controls the working power and time of the heat storage combustion system according to the changes between the preset baking curve and the real-time temperature.

[0020] Further preferably, the transmission system, automatic lifting system, temperature monitoring device, heat storage combustion system, and rotating device are controlled by a computer remote control system.

[0021] The present invention also provides a test method for a pilot test furnace of anti-burst performance of refractory castables, comprising the following steps:

[0022] 1) Pour the test casting material into a casting mold, vibrate and shape it, and then let it stand for curing to obtain a test casting body;

[0023] 2) The cured test casting body, casting mold, and mold support plate are transported to the bottom of the furnace body through the transmission system;

[0024] 3) The test casting body and casting mold are lifted by the automatic lifting system and installed at the bottom of the furnace together with the mold support plate;

[0025] 4) Turn on the temperature monitoring device and the heat storage combustion system, and bake the test casting according to the actual baking system curve of the casting in the steel plant during the actual production process;

[0026] 5) After baking is completed according to the baking system curve, the temperature monitoring device continues to work and records the actual temperature change curve;

[0027] 6) After the test casting is cooled naturally, the test casting, casting mold and mold support plate are removed from the bottom of the furnace by the automatic lifting system, and the cause of the burst is analyzed according to the degree of burst of the casting;

[0028] The transmission system, automatic lifting system, temperature monitoring device and heat storage combustion system are controlled by a computer remote control system.

[0029] The present invention also provides the application of the pilot test furnace for the anti-bursting performance of the refractory castables, which is used to evaluate the anti-bursting performance of the refractory castables of the steel ladle and the iron ladle.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The pilot test furnace provided in the present invention simulates the actual baking equipment of a steel plant, and is basically consistent with the on-site baking environment and conditions, including that the baking energy medium is coal gas or natural gas, and the simulation degree is high. The evaluation accuracy of the anti-burst performance of refractory castables is very high, which is beneficial to the research and application of refractory castables.

[0032] In the present invention, a large-volume sample is used for testing, and its thickness is generally basically consistent with the actual pouring thickness of the refractory castable at the bottom of the steel ladle or iron ladle of the steel plant. The internal vapor pressure of the sample during baking is basically consistent with the actual situation of the steel plant, which can effectively reflect the change of the internal vapor pressure of the sample with the baking time, thereby ensuring higher accuracy of the test.

[0033] The test furnace provided by the present invention is completed by one-button operation, which is simple and convenient to operate, is conducive to testing of multiple batches of castables, and can also test two samples at the same time, with high test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the main structure of a pilot test furnace for the anti-burst performance of refractory castables in the present invention;

[0035] Figure 2 It is a left-side structural schematic diagram of a rotating device of a pilot test furnace for anti-burst performance of refractory castables in the present invention;

[0036] Figure 3 It is a schematic diagram of the main structure of the test casting body and the casting mold of the present invention;

[0037] Figure 4 It is a top view schematic diagram of the test casting body and casting mold of the present invention;

[0038] Figure 5 It is a schematic diagram of the internal partition of the casting mold of the present invention.

[0039] Among them, 1-transmission system, 2-automatic lifting system, 3-test casting body, 4-casting mold, 4.1-mold partition, 5-mold support plate, 6-furnace body, 6.1-wall, 6.2-furnace shell, 7-furnace cover, 8-temperature monitoring device, 9-thermal storage combustion system, 9.1-air pipeline, 9.2-air pipeline bracket, 9.3-gas pipeline, 9.4-gas pipeline bracket, 9.5-fixed frame, 10-rotating device, 10.1-movable pulley block, 10.2-fixed pulley block, 11-furnace body bracket. DETAILED DESCRIPTION

[0040] In order to better explain the present invention, the main contents of the present invention are further explained below in conjunction with specific embodiments, but the contents of the present invention are not limited to the following embodiments.

[0041] Example 1

[0042] like Figures 1-2 The figure shows a pilot test furnace for the anti-bursting performance of refractory castables provided by the present invention, which is used to evaluate the bursting performance of steel and iron clad refractory castables. The pilot test furnace is composed of a transmission system 1, an automatic lifting system 2, a test casting body 3, a casting mold 4, a mold support plate 5, a furnace body 6, a furnace cover 7, a temperature monitoring device 8, a heat storage combustion system 9, a rotating device 10, an air pipeline 9.1, an air pipeline bracket 9.2, a gas pipeline 9.3, a gas pipeline bracket 9.4, and a computer remote control system.

[0043] The transmission system 1 is arranged outside the furnace body 6 and connected to the automatic lifting system 2, and is used to transport the test casting body 3 to the automatic lifting system 2 just below the furnace body 6, and the transportation process is controlled by a computer remote control system.

[0044] The automatic lifting system 2 is arranged directly below the furnace body 6. Its top receives the test casting 3 transmitted by the transmission system 1 and lifts the test casting 3, and is installed at the bottom of the furnace body 6 to support the test casting 3 until the test is completed. Its lifting process is controlled by a computer remote control system.

[0045] like Figures 3-4 As shown, the test casting body 3 is arranged in a casting mold 4. The test casting body 3 is obtained by pouring a casting material into the casting mold 4 and shaping it. After shaping, the test casting body 3 is used to measure its bursting performance.

[0046] like Figures 3-4 As shown, the height M of the casting mold 4 is between 250 and 400 mm, which is consistent with the actual thickness of the bottom of the steel ladle or iron ladle in the steel plant. The casting mold 4 is a circular structure, and the size of its bottom plate is larger than the diameter of the furnace body 6. A mold partition 4.1 is arranged inside the casting mold 4 to divide the casting mold 4 into multiple parts. The casting mold 4 and the mold partition 4.1 are made of steel material, and the maximum use temperature of the material is ≥1500℃. Figures 4-5 As shown, according to the specific conditions of the test, the casting mold 4 is divided into 1 to 4 parts by the mold partition 4.1, and 1 to 4 formulations can be tested simultaneously without affecting each other.

[0047] A mold support plate 5 is provided at the bottom of the casting mold 4 to support the casting mold 4. The mold support plate 5 is the same size as the bottom plate of the casting mold 4. The maximum operating temperature of the mold support plate 5 is ≥500°C, and the tensile strength is ≥500MPa. The size of the mold support plate 5 is larger than the bottom opening of the furnace body 6; after the automatic lifting system 2 lifts the test casting body 3 together with the casting mold 4, the test casting body 3 is transported from the bottom of the furnace body 6 to the furnace body 6, while the bottom plate of the casting mold 4 and the mold support plate 5 block the bottom of the furnace body 6.

[0048] The furnace body 6 is suspended above the ground by a furnace body support 11. The furnace body 6 is a bottomless cylindrical structure, which consists of a wall 6.1 and a furnace shell 6.2; the wall 6.1 is made of refractory bricks, and the furnace shell 6.2 is wrapped around the outside of the wall 6.1. When conducting a test on the anti-burst performance of the castable, the mold support plate 5, the casting mold 4 located on the mold support plate 5, and the test casting body 3 located inside the casting mold 4 are lifted by the automatic lifting system 2 and installed in the furnace body 6 as the bottom of the furnace body 6. The furnace body support 11 can be composed of at least three steel columns evenly distributed at the bottom of the furnace body 6 or a steel ring with an opening, and the opening is used for the transmission system 1 to transmit the test casting body 3 into the bottom of the furnace body 6. Among them, refractory bricks have good high temperature resistance and heat preservation functions, and their maximum use temperature is ≥1600℃, and the volume density is 2.5~3.0g / cm 3 The thermal conductivity is ≤2.0W / m·K.

[0049] The furnace cover 7 is arranged on the top of the furnace body 6. The furnace cover 7 is made of steel material. The lower part of the furnace cover 7 is covered with a refractory material with a heat-insulating function. The maximum use temperature of the refractory material is ≥1400°C.

[0050] The temperature monitoring device 8 is installed on the furnace cover 7, and uses an infrared temperature measurement method to monitor the internal temperature of the test furnace and transmits it to the computer remote control system in a timely manner.

[0051] The heat storage combustion system 9 is arranged at the center of the furnace cover 7 and is connected to the furnace body 6 for baking the test casting inside the furnace body 6 .

[0052] The heat storage combustion system 9 is provided with an air pipeline 9.1 and a gas pipeline 9.3, which are used to transport air and gas / natural gas to the heat storage combustion system 9 for combustion, and bake the test cast body 3 inside the furnace body 6; the air pipeline 9.1 and the gas pipeline 9.3 are respectively provided with an air pipeline bracket 9.2 and a gas pipeline bracket 9.4, which fix the air pipeline 9.1 and the gas pipeline 9.3 on a fixing frame 9.5, and the fixing frame 9.5 is used to support the pipelines of the heat storage combustion system 9.

[0053] The rotating device 10 is composed of a movable pulley block 10.1 and a fixed pulley block 10.2. The movable pulley block 10.1 is connected to the furnace cover 7, and the fixed pulley block 10.2 is connected to the fixed pulley block 10.1. The movable pulley block 10.1 and the fixed pulley block 10.2 are connected to the pulley block motor. Under the action of the movable pulley block 10.1 and the fixed pulley block 10.2, the rotating device 10 can open, close, and adjust the height of the furnace cover 7. The computer remote control system adjusts the height of the furnace cover 7 by controlling the movement of the pulley block motor.

[0054] The computer remote control system is placed in the operation room and is mainly used to set, start and end the baking system program; the computer remote control system transmits instructions to the transmission system 1, the automatic lifting system 2, the temperature monitoring device 8, the heat storage combustion system 9, the rotating device 10, etc.; collects the temperature data sent by the temperature monitoring device 8, and controls the working power and time of the heat storage combustion system 9 according to the changes between the preset baking curve and the real-time temperature.

[0055] Example 2

[0056] The pilot test furnace for the anti-bursting performance of refractory castables in Example 1 is used to evaluate the bursting performance of steel and iron clad refractory castables. The test method includes the following steps:

[0057] Step 1) Separate and fix the casting mold 4 by the mold partition 4.1 according to the number of recipes determined in the test plan, then pour the casting materials of different recipes into the casting mold 4 and vibrate them to form them at the same time. After forming, let them stand and cure according to the actual curing system of the actual production process of the steel ladle / iron ladle in the steel plant to obtain the test casting body 3; the thickness of the casting mold 4 and the test casting body 3 is consistent with the actual casting thickness of the bottom of the steel ladle and iron ladle in the steel plant.

[0058] Step 2) Start the computer remote control system and transport the cured test casting body 3 together with the casting mold 4 and the mold support plate 5 to the automatic lifting system 2 directly below the furnace body 6 through the transmission system 1.

[0059] Step 3) The test casting body 3 , the casting mold 4 and the mold support plate 5 are lifted by the automatic lifting system 2 and supported at the bottom of the furnace body 6 .

[0060] Step 4) According to the actual baking system curve of the ladle / iron ladle casting body of the steel plant in the actual production process, the baking system curve is set in the computer remote control system. The actual baking system curve of the steel plant is divided into three stages: low fire, medium fire and high fire. According to the characteristics of the castable, the castable burst will only occur in the medium fire stage. Therefore, in order to improve the experimental efficiency, the baking system curve of the pilot test furnace of the present invention only includes two stages: low fire and medium fire.

[0061] The computer remote control system controls the opening and closing degree of the furnace cover 7, turns on the temperature monitoring device 8 and the heat storage combustion system 9, and starts baking the test casting 3.

[0062] Step 5) After baking is completed according to the baking system curve, the temperature monitoring device 8 continues to work, and the computer remote control system continues to record the change curve of the actual temperature.

[0063] Step 6) Cool naturally for 8 hours, and then the computer remote control system controls the automatic lifting system 2 to remove the test casting 3 from the test furnace. The cause of the bursting is analyzed according to the degree of bursting of the casting material, and the best production plan can be determined.

Claims

1. A pilot test furnace for the anti-burst performance of refractory castables, characterized by: include: A furnace body (6) is used to provide a baking space for the test casting body (3); The thickness of the test casting (3) is consistent with the thickness of the casting product in the actual production process; A furnace cover (7) is installed on the top of the furnace body (6); The heat storage combustion system (9) is arranged on the furnace cover (7) and is connected to the furnace body (6) and is used to bake the test casting (3) by burning coal gas / natural gas.

2. The pilot test furnace for the anti-burst performance of refractory castables according to claim 1, characterized in that: The furnace body (6) is arranged in an overhead manner, and the bottom of the furnace body (6) is open; the furnace body (6) comprises a wall body (6.1) and a furnace shell (6.2) wrapped around the outside of the wall body (6.1); the wall body (6.1) is made of refractory bricks; the maximum use temperature of the refractory bricks is ≥1600°C, and the volume density is 2.5-3.0g / cm 3 , thermal conductivity ≤2.0W / m·K.

3. The pilot test furnace for the anti-burst performance of refractory castables according to claim 2, characterized in that: It also comprises an automatic lifting system (2) which is arranged below the furnace body (6) and is used to lift the test casting body (3) and allow it to enter through the bottom opening of the furnace body (6) and be installed in the furnace body (6).

4. The pilot test furnace for the anti-burst performance of refractory castables according to claim 3, characterized in that: The regenerative combustion system (9) is provided with an air pipeline (9.1) and a gas pipeline (9.3) for conveying air and gas / natural gas to the regenerative combustion system (9) for combustion, thereby baking the test casting (3).

5. The pilot test furnace for the anti-burst performance of refractory castables according to claim 4, characterized in that: It also includes a temperature monitoring device (8) which is installed on the furnace cover (7) and uses an infrared temperature measurement method to monitor the internal temperature of the furnace body (6).

6. The pilot test furnace for the anti-burst performance of refractory castables according to claim 5, characterized in that: It also includes a transmission system (1) which is arranged outside the furnace body (6) and connected to the automatic lifting system (2) and is used to transmit the test casting body (3) to the automatic lifting system (2) below the furnace body (6).

7. The pilot test furnace for the anti-burst performance of refractory castables according to claim 6, characterized in that: It also includes a casting mold (4) for pouring a casting material into the casting mold for shaping to obtain a test casting body (3); the casting mold (4) is provided with a mold partition (4.1) for separating the internal space of the casting mold (4); the bottom of the casting mold (4) is provided with a mold support plate (5), and the size of the mold support plate (5) is larger than the bottom opening of the furnace body (6); after the automatic lifting system (2) lifts the test casting body (3) together with the casting mold (4), the test casting body (3) is transported into the furnace body (6) through the bottom opening of the furnace body (6), and the mold support plate (5) blocks the bottom opening of the furnace body (6).

8. The pilot test furnace for anti-burst performance of refractory castables according to any one of claims 1 to 7, characterized in that: It also includes a computer remote control system, which is arranged in the operating room and is used to set, start and end the baking system program; the computer remote control system collects temperature data sent by the temperature monitoring device (8), and controls the working power and time of the heat storage combustion system (9) according to the change between the preset baking curve and the real-time temperature.

9. A test method for the pilot test furnace of the anti-burst performance of refractory castables according to claim 8, characterized in that: The following steps are involved: 1) pouring the test casting material into a casting mold (4), vibrating and molding it, and then standing it for curing after molding to obtain a test casting body (3); 2) transporting the cured test casting body (3), the casting mold (4), and the mold support plate (5) together to the bottom of the furnace body (6) through the transmission system (1); 3) The test casting body (3) and the casting mold (4) are lifted by the automatic lifting system (2) and installed together with the mold support plate (5) at the bottom of the furnace body (6); 4) starting the temperature monitoring device (8) and the heat storage combustion system (9), and baking the test casting (3) according to the actual baking system curve of the casting in the steel plant during the actual production process; 5) After baking is completed according to the baking system curve, the temperature monitoring device (8) continues to work and records the actual temperature change curve; 6) After the test casting (3) is cooled naturally, the test casting (3), the casting mold (4), and the mold support plate (5) are removed from the bottom of the furnace (6) by the automatic lifting system (2), and the cause of the burst is analyzed according to the degree of burst of the casting material; The transmission system (1), the automatic lifting system (2), the temperature monitoring device (8), and the heat storage combustion system (9) are controlled by a computer remote control system.

10. Application of the pilot test furnace for anti-burst performance of refractory castables according to any one of claims 1 to 8, characterized in that: Used to evaluate the anti-burst performance of refractory castables in steel ladles and iron ladles.

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