Thermal protection particle covering agent and preparation method thereof
By mixing powder insulation, starch, potassium nitrate, sodium bicarbonate and yeast in a specific proportion and granulating under pressure, a thermal protection particle covering agent is solved, and the problem of troubles in use and poor insulation effect of traditional casting riser insulation materials is solved. , achieving more efficient insulation effect and lower dosage, reducing environmental pollution.
Patent Information
- Application Number
- CN202411276419.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2024-12-13
AI Technical Summary
The insulation materials of traditional casting risers have problems with troubles in use, poor insulation effect and carbon increase pollution. The powder insulation is burning too fast at high temperatures and is difficult to evenly distribute, resulting in poor dust and heat preservation effects.
Using thermal protection particle covering agent, by mixing powder insulation, starch, potassium nitrate, sodium bicarbonate and yeast in a specific proportion and granulating under pressure, forming a granular particle structure, reducing dust loss and improving insulation effect .
It achieves better insulation function and lower dosage, reduces environmental pollution, improves thermal effect, and maintains continuous insulation effect for 16 hours at a high temperature of 1600℃.
Smart Images
Figure CN119114848A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of smelting, and in particular to a thermal protection particle covering agent and a preparation method thereof. Background Art
[0002] Riser insulation is one of the key factors in controlling casting quality. The main functions of the riser are exhaust, slag removal, and shrinkage compensation of molten steel. Traditional foundries often use plant ash, fly ash, and carbonized rice husks as riser heat insulation materials, which have the disadvantages of being difficult to use and having poor insulation effects. They may also cause carbon pollution to steel grades, affecting the quality of riser steel remelting.
[0003] The Chinese invention patent with application number: 201110287106, entitled "A Casting Riser Insulation Agent", discloses a powder insulation agent. Although its insulation effect is higher than that of traditional methods, it has many defects in use. For example, various powder insulation agents or covering agents burn too fast at a high temperature of 1000°C, and the components are reduced to ash before they are fully integrated and function. In addition, the powder feeding is difficult to control, and leakage and powder flying will occur, which will cause great damage to the operating environment and easily affect the sight of the operators during operation. The dust generated during the feeding process also causes unnecessary waste (loss of about 20%), so the heat preservation effect is poor, which will affect the quality of industrial products. Summary of the invention
[0004] In view of the above problems, the present application provides a heat protection particle covering agent and a preparation method thereof. The heat protection particle covering agent does not cause dust, has better heat preservation function, and the dosage is lower than that of powder heat preservation agent. Using the heat protection particle covering agent, the riser heat preservation time can reach 16 hours.
[0005] The first aspect of the present application provides a heat protection particle covering agent, which comprises the following components in percentage by weight: 60-75% of a powdered heat preservation agent, 10-15% of water, and 5-20% of starch.
[0006] Different from the existing technology: after starch is gelatinized by water, the molecular chains in the molecule are relatively loose and have a higher viscosity, which can bond the various components in the powder insulation agent, making it granulable and finally forming particles. The heat protection particle covering agent allows the insulation powder to be evenly distributed, while reducing dust loss during use, reducing pollution to the environment, and improving the thermal effect.
[0007] Furthermore, the heat protection granule covering agent also includes 0.5-1% yeast.
[0008] Furthermore, the thermal protection particle covering agent also includes 1-5% potassium nitrate.
[0009] Furthermore, the heat protection particle covering agent also includes 0.1-0.5% sodium bicarbonate.
[0010] Furthermore, the starch is amylopectin.
[0011] Furthermore, the powder thermal insulation agent comprises the following components in percentage by mass: Al 10-40%; MgO 5-30%; quartz 5-30%; graphite 3-15%; and magnesium aluminum silicate 10-40%.
[0012] Furthermore, the particle size of the thermal protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0013] Furthermore, the powder particle size of the powder heat-insulating agent is 10 to 200 meshes.
[0014] The second aspect of the present application provides a method for preparing a heat-protective granular covering agent, comprising the following steps: mixing 60-75% by mass of a powdered heat-insulating agent, 10-15% by mass of water, and 5-20% by mass of starch, and then performing pressure granulation and drying to obtain the heat-protective granular covering agent.
[0015] Furthermore, the invention comprises the following steps: uniformly mixing 5-20% by weight of amylopectin, 1-5% by weight of potassium nitrate, 0.1-0.5% by weight of sodium bicarbonate, 0.5-1% by weight of yeast, 10-15% by weight of water and 60-75% by weight of a powdered heat-insulating agent, performing pressure granulation and drying to obtain the heat-protective granule covering agent; the powdered heat-insulating agent comprises the following components in weight percentage: Al 10-40%; MgO 5-30%; quartz 5-30%; graphite 3-15%; and magnesium aluminum silicate 10-40%.
[0016] Furthermore, the mixing temperature is controlled at 10°C to 30°C, and the mixing time is not less than 40 minutes.
[0017] Furthermore, the shapes of the heat protection particle covering agent include columnar, spherical, plate-shaped and square.
[0018] Different from the existing technology, the heat protection granule covering agent includes starch, potassium nitrate, sodium bicarbonate, yeast and water. Pullulan is used as a binder, and sodium bicarbonate provides an alkaline environment to improve the bonding ability of pullulan; yeast reacts with pullulan to improve the bonding force of pullulan, and forms some pores in the particles to reduce the particle density. Starch, as a strong binder, can bond the various powder components to make them granulable, and finally form particles to stabilize combustion. The heat protection granule covering agent allows the thermal insulation powder to be evenly distributed, while reducing dust loss during use, reducing pollution to the environment, and improving the thermal effect.
[0019] The above-mentioned records related to the invention content are only an overview of the technical solution of the present application. In order to enable ordinary technicians in the field to more clearly understand the technical solution of the present application, and then implement it according to the written contents of the specification, and to make the above-mentioned purpose and other purposes, features and advantages of the present application easier to understand, the specific implementation mode and drawings of the present application are explained below. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawings are only used to illustrate the principles, implementation methods, applications, characteristics and effects of the specific embodiments of the present application and other related contents, and shall not be considered as limitations of the present application.
[0021] In the drawings of the specification:
[0022] Figure 1 It is the thermal protection particle covering agent prepared in Example 1.
[0023] Figure 2 It is a comparison diagram of Example 1 and Comparative Example 1 with the addition of a riser (just added).
[0024] Figure 3 It is a comparison diagram of Example 1 and Comparative Example 1 after adding a riser (6 hours later).
[0025] Figure 4 It is a comparison chart of Example 1 and Comparative Example 1 after adding a riser (13 hours later).
[0026] Figure 5 It is a comparison chart of Example 1 and Comparative Example 1 after adding a riser (27 hours later).
[0027] Figure 6 This is a diagram of the outer surface of the riser added in Example 1.
[0028] Figure 7 This is a cross-sectional view of the riser added in Example 1.
[0029] Figure 8 This is a surface diagram of the riser added in Comparative Example 1.
[0030] Fig. 9 1 is a cross-sectional view of the riser added in Comparative Example 1.
[0031] Fig.10 This is a cross-section of a riser without the use of heat-protective granular covering agent or powder insulation.
[0032] Fig.11 This is a cross-sectional view of a riser using powder insulation.
[0033] Fig.12 This is a cross-sectional view of a riser using 1% of the heat protection particle covering agent of Example 1. DETAILED DESCRIPTION
[0034] In order to explain in detail the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.
[0035] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.
[0036] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.
[0037] In the description of this application, the term "and / or" is an expression used to describe the logical relationship between objects, indicating that three relationships may exist, for example, A and / or B, which means: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this article generally indicates that the objects before and after are in an "or" logical relationship.
[0038] In the present application, terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship of quantity, priority or sequence between these entities or operations.
[0039] Without further limitations, in this application, the words "include", "comprises", "has" or other similar expressions used in the sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those limited elements, but also other elements not explicitly listed, or also include elements inherent to such process, method or product.
[0040] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than", "less than", "exceed" and the like are understood to exclude the number itself; expressions such as "above", "below", "within" and the like are understood to include the number itself. In addition, in the description of the embodiments of this application, "multiple" means more than two (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups", "multiple times", etc., unless otherwise clearly and specifically limited.
[0041] The heat protection granular covering agent described in this application is further developed on the basis of the inventor's own Chinese invention patent with application number: 201110287106, entitled "A casting riser insulation agent". In the actual production process, the inventor found that the powder insulation agent prepared by a casting riser insulation agent had some defects, and conducted targeted research on this. The experimental results also found that the use of granular covering agents can solve the historical technical problem of heat protection covering agent pollution on the surface of molten steel transfer in blast furnaces. The powder insulation agent described in this application is the powder insulation agent disclosed in application number: 201110287106, entitled "A casting riser insulation agent".
[0042] The first aspect of the present application provides a heat protection particle covering agent, which comprises the following components in percentage by weight: 60-75% of a powdered heat preservation agent, 10-15% of water, and 5-20% of starch.
[0043] Different from the existing technology: after starch is gelatinized by water, the molecular chains in the molecule are relatively loose, with high viscosity, which can bond the components in the powder insulation agent, making it granulable and finally forming particles. The formation of granular form allows the components in the insulation powder to be evenly distributed, while reducing dust loss during use, reducing pollution to the environment, and improving thermal effect.
[0044] Furthermore, the heat protection granule covering agent also includes 0.5-1% yeast. Yeast microorganisms decompose amylopectin into smaller molecules, making amylopectin more viscous. The yeast fermentation process forms bubbles in the granules, which plays a role in reducing the density of the granules.
[0045] Furthermore, the thermal protection particle covering agent also includes 1-5% potassium nitrate.
[0046] In the metallurgical smelting furnace, potassium nitrate will directly contact the high-temperature molten iron or copper to produce oxides and oxygen. 3) is an oxidant, and iron (Fe) is a reducing agent. The oxygen atoms in potassium nitrate are reduced to oxygen by iron, but it needs to absorb heat. This reaction will produce a large amount of oxygen, which will assist the starch component and the powder heat preservation agent component to burn, causing a violent reaction and generating a large amount of gas. In this application, the particle structure of the heat protection particle covering agent is better than the powder in terms of permeability, the gas can be quickly discharged, and the instantaneous heat release effect is good.
[0047]
[0048] Similarly, the starch component in the granules can also be used as a reducing agent. Starch will crack at high temperatures, producing combustion-supporting gases such as carbon monoxide, hydrogen, and oxygen. Gas channels will also be formed, causing the riser insulation layer to form a loose structure.
[0049] Furthermore, the heat protection granule covering agent also includes 0.1-0.5% sodium bicarbonate. Sodium bicarbonate provides an alkaline environment and improves the bonding ability of amylopectin.
[0050] In some embodiments, during the material mixing process, sodium bicarbonate is first dissolved in water and then added to the mixed material in the form of atomized alkaline water to achieve a better mixing effect.
[0051] Furthermore, the starch is amylopectin, and the viscosity of amylopectin is higher than that of amylose.
[0052] Furthermore, the powder thermal insulation agent comprises the following components in percentage by mass: Al 10-40%; MgO 5-30%; quartz 5-30%; graphite 3-15%; and magnesium aluminum silicate 10-40%.
[0053] Furthermore, the particle size of the thermal protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 The particle size is 2MM smaller and should not be larger than 5MM. If it is too small, the effective component content is small and it is easy to generate dust. If it is too large, it will affect its ductility and dispersion in the furnace. The density is controlled at 2.8-3.2kg / m 3 It can ensure that the particles cover the surface of the boiler water and play a heat preservation effect.
[0054] Furthermore, the powder particle size of the powder heat-insulating agent is 10 to 200 meshes.
[0055] The second aspect of the present application provides a method for preparing a heat-protective granular covering agent, comprising the following steps: mixing 60-75% by mass of a powdered heat-insulating agent, 10-15% by mass of water, and 5-20% by mass of starch, and then performing pressure granulation and drying to obtain the heat-protective granular covering agent.
[0056] Furthermore, the invention comprises the following steps: uniformly mixing 5-20% by weight of amylopectin, 1-5% by weight of potassium nitrate, 0.1-0.5% by weight of sodium bicarbonate, 0.5-1% by weight of yeast, 10-15% by weight of water and 60-75% by weight of a powdered heat-insulating agent, performing pressure granulation and drying to obtain the heat-protective granule covering agent; the powdered heat-insulating agent comprises the following components in weight percentage: Al 10-40%; MgO 5-30%; quartz 5-30%; graphite 3-15%; and magnesium aluminum silicate 10-40%.
[0057] Different from the existing technology, the heat protection granule covering agent includes starch, potassium nitrate, sodium bicarbonate, yeast and water. Pullulan is used as a binder, and sodium bicarbonate provides an alkaline environment to improve the bonding ability of pullulan; the addition of yeast will also increase the bonding force of pullulan, form bubbles, and reduce the density of the heat preservation granules. Pullulan, as a strong binder, can bond the powder heat preservation components, making them granulable, and finally forming granules, which has the effect of stabilizing combustion.
[0058] Through the preparation method of the present application, the volume of the powder heat preservation agent after compression is 1 / 3 of the original volume. Therefore, under the same volume unit, the granules can release more than twice the calorific value of the powder. Therefore, the granules of the same volume unit have higher thermal radiation value, stronger pressure and greater pressure than the powder heat preservation agent.
[0059] Compared with powder insulation agent, heat protection granule covering agent is easier to deliver by automated manipulator and trough-shaped automated feeding belt through pressurized granulation, which changes the dangerous feeding method of workers in 1600℃ high temperature furnace, avoids the safety hazard and material waste caused by dust, improves production safety, improves work efficiency, reduces labor intensity, saves costs, and saves energy and reduces emissions.
[0060] Potassium nitrate is used as an oxidant. It releases oxygen during the reaction process when heated, which helps the material burn and improves the combustion intensity. Starch is used as a reducing agent. It will crack at high temperature, and combustion-supporting gases such as carbon monoxide, hydrogen, and oxygen will be produced. It will also form gas channels, increase the specific surface area, and make the riser insulation layer form a loose structure, which is conducive to the introduction of air and has a combustion-supporting effect.
[0061] The shape of the particles allows the components in the thermal insulation powder to be evenly distributed, while reducing dust losses during use, reducing pollution to the environment, and improving thermal effects.
[0062] Furthermore, the mixing temperature is controlled at 10°C to 30°C, and the mixing time is not less than 40 minutes.
[0063] The control of mixing temperature and time allows the yeast to ferment the starch more fully and the components to be dispersed more evenly.
[0064] Furthermore, the pressure of pressurized granulation is ≤100kg / cm 2 During the pressurized granulation process, the pressure should not be too high. Too high pressure will make the particle density too high and the mass too large. At the same time, the pores inside the particles will become less, the air permeability will be reduced, and the loose air permeability structure formed inside the particles will be destroyed.
[0065] In some embodiments, a granulator or tablet press is used to granulate the mixed components. The shapes of the granules include but are not limited to cylindrical, spherical, plate-shaped, and square.
[0066] In some embodiments, the granulation is dried in a dryer after completion.
[0067] In some embodiments, the outer layer of the dried particles is coated with a thin layer of paraffin. This step includes: putting the dried particles into a thin paraffin liquid with a solid content of 2-5% for 3S-10S and rolling it. This step can protect the particles from falling off and getting wet.
[0068] The shapes of the heat protection particle covering agent include columnar, spherical, plate-like and square.
[0069] In this embodiment, the powder thermal insulation agent includes the following components in percentage by mass: 30% Al, 20% MgO, 15% quartz, 5% graphite, and 30% magnesium aluminum silicate.
[0070] In this embodiment, sodium bicarbonate is first dissolved in water and then added to the mixed material in the form of atomized alkaline water.
[0071] 5-20% amylopectin, 1-5% potassium nitrate, 0.1-0.5% sodium bicarbonate, 0.5-1% yeast, 10-15% water and 60-75% powdered heat-insulating agent are mixed, pressurized and granulated, and then dried to obtain the heat-protective particle covering agent; the powdered heat-insulating agent includes the following components in mass percentage: Al 10-40%; MgO 5-30%; quartz 5-30%; graphite 3-15%; magnesium aluminum silicate 10-40%.
[0072] Example 1: A thermal protection particle covering agent
[0073] 10% amylopectin, 4% potassium nitrate, 0.8% yeast and 70% powdered heat preservation agent are put into a reaction kettle and stirred;
[0074] Dissolve 0.2% sodium bicarbonate in 15% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0075] The temperature of the reactor was controlled at 30°C, and the stirring time was 40 minutes. The discharge tank was then left to stand for more than 1 hour, and then pressurized granulation was performed using a granulator with a granulation pressure of 100 kg / cm 2After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0076] Example 2: A thermal protection particle covering agent
[0077] 20% amylopectin, 4% potassium nitrate, 0.5% yeast and 60% powdered heat preservation agent are put into a reaction kettle and stirred;
[0078] Dissolve 0.5% sodium bicarbonate in 15% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0079] The temperature of the reactor was controlled at 30°C, and the stirring time was 40 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 50 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0080] Example 3: A thermal protection particle covering agent
[0081] 5% amylopectin, 4% potassium nitrate, 0.6% yeast and 75% powdered heat preservation agent are put into a reaction kettle and stirred;
[0082] Dissolve 0.4% sodium bicarbonate in 15% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0083] The temperature of the reactor was controlled at 20°C, and the stirring time was 50 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 50 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0084] Example 4: A thermal protection particle covering agent
[0085] 15% amylopectin, 1% potassium nitrate, 0.9% yeast and 70% powdered heat preservation agent are put into a reaction kettle and stirred;
[0086] Dissolve 0.1% sodium bicarbonate in 13% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0087] The temperature of the reactor was controlled at 20°C, and the stirring time was 50 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 60 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0088] Example 5: A thermal protection particle covering agent
[0089] 10% amylopectin, 3.5% potassium nitrate, 1% yeast and 75% powdered heat preservation agent are put into a reactor and stirred;
[0090] Dissolve 0.5% sodium bicarbonate in 10% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0091] The temperature of the reactor was controlled at 15°C, and the stirring time was 60 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 60 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0092] Example 6: A thermal protection particle covering agent
[0093] 15% amylopectin, 4% potassium nitrate, 0.7% yeast and 65% powdered heat preservation agent are put into a reaction kettle and stirred;
[0094] Dissolve 0.3% sodium bicarbonate in 15% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0095] The temperature of the reactor was controlled at 15°C, and the stirring time was 60 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 80 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0096] Example 7: A thermal protection particle covering agent
[0097] 10% amylopectin, 5% potassium nitrate, 0.5% yeast and 69% powdered heat preservation agent are put into a reaction kettle and stirred;
[0098] Dissolve 0.5% sodium bicarbonate in 15% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0099] The temperature of the reactor was controlled at 10°C, and the stirring time was 90 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 80 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0100] Example 8: A thermal protection particle covering agent
[0101] 18% amylopectin, 2% potassium nitrate, 1% yeast and 63.5% powdered heat preservation agent are put into a reactor and stirred;
[0102] Dissolve 0.5% sodium bicarbonate in 15% water to form atomized alkaline water; add the atomized water into the stirring reactor through an atomizing device;
[0103] The temperature of the reactor was controlled at 10°C, and the stirring time was 90 minutes. The discharge tank was then left to stand for more than 1 hour, and then the pelletizer was used for pressurized pelletization at a pelletizing pressure of 40 kg / cm 2 After drying, a heat protection particle covering agent is obtained. The particle size of the heat protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
[0104] Comparative Example 1: After mixing 70% of the powdered heat-insulating agent and 30% of the adhesive, the mixture was granulated under pressure using a granulator at a granulation pressure of 100 kg / cm 2 After drying, the heat protection particle covering agent of Comparative Example 1 is obtained.
[0105] Example 9
[0106] Two 1701-2 arches were cast, with risers at both ends having dimensions of 640×960×750, and the amount of molten steel in the risers being about 2860 kg. The heat protection particle covering agent was added to each riser at a ratio of 1.75%. The heat protection particle covering agent of Example 1 was used for two risers of one of the two arches, and the heat protection particle covering agent of Comparative Example 1 was used for the other two risers. The heat protection particle covering agent of Example 1 was used for one riser of the other arch, and the heat protection particle covering agent of Comparative Example 1 was used for the other three risers.
[0107] Depend on Figure 1-Figure 5 It can be seen that under the same dosage, from the riser surface temperature and shrinkage effect in each period, the addition of Example 1 is significantly stronger than that of Comparative Example 1.
[0108] like Figure 6 , 7As shown in the figure, the result of casting using the final riser shrinkage compensation of Example 1 is that there is an obvious concave center on the riser, which is about 300mm deep, and the structure is relatively dense and free of inclusions about 300mm above the bottom of the riser. Under the condition of ensuring thermal insulation and riser shrinkage compensation, the proportion of Example 1 can be reduced to 0.9-1.0%, which can achieve better results.
[0109] like Figure 8 , 9 As shown, the final riser shrinkage feeding result using Comparative Example 1 has no obvious concave center on the riser, and the inclusions in the riser are basically fed to the bottom.
[0110] Example 10
[0111] A 1701-2 archway was cast, with the risers at both ends measuring 640×960×750, and the amount of molten steel in the risers was about 2860 kg. One riser used the thermal protection particle covering agent of Example 1, and one riser used the powder insulation agent, with a proportion of 1%; the other two risers did not use insulation particles and powder insulation agents. The results are shown in Figure 10-12 As shown, Fig.10 The bottom of the riser without insulation particles is penetrated by bubbles. Fig.11 For the riser with powder insulation, the air bubble is only 3cm away from the bottom; Fig.12 The heat protection particle covering agent of Example 1 has almost no bubbles and is highly dense.
[0112] The heat protection particle covering agent prepared in this embodiment can maintain a continuous heat release and heat preservation time of 16 hours, and finally only 3% of the mass density is less than 1.5 kg / m 3 Ash residual powder.
[0113] Finally, it should be noted that although the above embodiments have been described in the specification and drawings of this application, this does not limit the scope of patent protection of this application. All technical solutions generated by replacing or modifying equivalent structures or equivalent processes based on the essential concept of this application using the contents recorded in the specification and drawings of this application, as well as directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, are included in the scope of patent protection of this application.
Claims
1. A heat protection particle covering agent, characterized in that: The heat protection particle covering agent comprises the following components in percentage by mass: 60-75% of powdered heat-insulating agent, 10-15% of water and 5-20% of starch.
2. The heat protection particle covering agent according to claim 1, characterized in that The heat protection granule coating agent also includes 0.5-1% yeast.
3. The heat protection particle covering agent according to claim 1, characterized in that: The heat protection granule covering agent also includes 1-5% potassium nitrate.
4. The heat protection particle covering agent according to claim 1, characterized in that The heat protection particle covering agent also includes 0.1-0.5% sodium bicarbonate.
5. The heat protection particle covering agent according to claim 1, characterized in that: The starch is amylopectin.
6. The heat protection particle covering agent according to claim 1, characterized in that: The powder thermal insulation agent comprises the following components in mass percentage: Al 10-40%, MgO 5-30%, quartz 5-30%, graphite 3-15%, and magnesium aluminum silicate 10-40%. The powder particle size in the powder thermal insulation agent is 10-200 meshes.
7. The heat protection particle covering agent according to claim 1, characterized in that The particle size of the thermal protection particle covering agent is 2 to 5 mm, and the density is 2.8 to 3.2 kg / m 3 .
8. A method for preparing a heat protection particle covering agent, characterized in that: The following steps are involved: The heat protection granule covering agent is obtained by mixing 60-75% by mass of a powdered heat-insulating agent, 10-15% by mass of water and 5-20% by mass of starch, and then performing pressure granulation and drying.
9. The preparation method according to claim 8, characterized in that: The following steps are involved: The heat protection particle covering agent is obtained by mixing 5-20% amylopectin, 1-5% potassium nitrate, 0.1-0.5% sodium bicarbonate, 0.5-1% yeast, 10-15% water and 60-75% powder heat preservation agent in mass percentage, and then performing pressure granulation and drying. The powder heat preservation agent comprises the following components in mass percentage: Al 10-40%; MgO 5-30%; quartz 5-30%; graphite 3-15%; and magnesium aluminum silicate 10-40%.
10. The preparation method according to claim 8, characterized in that: The shapes of the heat protection particle covering agent include columnar, spherical, plate-like and square.