The cause of slagging in ladle slag line

 1. For a long time to be poured, the top slag of molten steel cools and crusts, causing slagging on the ladle slag line.

(1) The cold heading steel process of Shaoguan Steel Plant requires bottom blowing of argon after the calcium treatment, weak blowing for 12-20 minutes. During the weak blowing process, the edge of the slag layer on the surface of the molten steel is basically in a static state. After a long period of temperature loss, the slag temperature continues decrease, the slag layer close to the ladle wall will solidify at the position of the ladle slag line, causing slagging on the ladle wall.
(2) The smelting cycle of the converter is shorter than the smelting cycle of the LF refining furnace, the pouring order is inadequate, the smelting speed of the previous process is too fast, the backlog of molten steel in the refining area is serious, and the waiting time is too long after the refining and smelting is completed until the continuous casting and casting. This is the main cause of slagging in the ladle slag line.

2. The Al2O3 content in the cold heading steel slag system is high, and the molten steel slag is sticky. After the refining is completed, the molten steel will solidify and condense at the position of the ladle slag line as the temperature of the slag surface decreases during the process of quenching.
According to field observations, when smelting aluminum killed steel, the ladle slag line is prone to slagging, while when smelting silico-manganese killed steel, the ladle slag line is slightly sticky.
The content of Al2O3 in aluminum killed steel slag is high [2]. In order to ensure the purity of molten steel, the amount of lime added is also large, forming a thicker and denser slag crust; silico-manganese killed steel does not contain Als, which produces Al?O? is also very small, so the amount of lime added is small and the slag layer formed is thin. It can be inferred that ladle slagging is greatly affected by the content of Al?O? in the slag.

3. The ladle slag line bricks are eroded seriously, causing depressions and slagging easily. Ladle slag line bricks refer to refractory bricks built from the third to the eighth layer of bricks from the bottom of the ladle mouth. After the ladle is filled with steel, the molten steel level fluctuates up and down with the amount of molten steel. When the converter smelting is finished, the partial oxide slag in the furnace is poured into the ladle along with the molten steel, commonly known as "slag". Sub-refining and slagging are used to remove excess oxygen in molten steel, that is, "deoxidation". The deoxidized slag is reduced slag.
As the alkalinity in the slag changes, the refractory bricks on the ladle wall that contact the slag are gradually dissolved and fall off, forming a depression in the ladle wall. When the alkalinity in the slag stabilizes, the slag and the ladle slag line bricks are mutually dissolved and combined to form slagging. The recessed wall of the slag will hang support points for the slagging, making slagging more and more easier.
In order to save costs and increase the turnover rate of the ladle, the ladle slag line bricks are not repaired in time after being etched, or the standard use is reduced, which greatly increases the probability of ladle slagging. Ladle slag line bricks have poor quality, poor corrosion resistance, poor permeability resistance, and quality problems such as cracks, which accelerate the erosion of the ladle slag line bricks and accelerate the slagging of the ladle slag line.

We Changxing Refractory Material Co.,LTD is professional manufacturer and supplier of refractory materials for more than 30 years. Our high quality magnesia carbon bricks are good sold to many countries say South Africa, Bangladesh, Indonesia, Malaysia, etc. Shall any interests, welcome to contact us. Our team would make best to be your reliable partner.

Article Source:The cause of slagging in ladle slag line
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: info@cxrefractories.com
Website:http://www.cxrefractories.com

Production process of cold head series molten steel in a steel making plant

 1. Converter → LF furnace → vacuum RH furnace → billet continuous caster.

2. Converter → vacuum RH furnace → LF furnace → billet continuous caster.
3. Converter → LF furnace → billet continuous caster.
After the LF furnace exits the station, the slagging is cooled during the pouring process, and the crust is still hung at the position of the ladle slag line after the molten steel is poured. This makes the ladle cleaning operation more difficult and workload, and the reuse of the steel slag left by the ladle will cause problems.

For example: the slagging on the wall of the ladle hangs in the air after the casting of the continuous caster, and falls to the bottom of the ladle under the action of gravity to form slagging at the bottom of the ladle. At the same time, some steel slag will be scattered in the ladle nozzle, blocking the nozzle, causing the molten steel to be unable to start pouring after reaching the continuous caster platform.

We Changxing Refractory Material Co.,LTD is professional manufacturer and supplier of refractory materials for more than 30 years. Our high quality magnesia carbon bricks are good sold to many countries say South Africa, Bangladesh, Indonesia, Malaysia, etc. Shall any interests, welcome to contact us. Our team would make best to be your reliable partner!

Article Source:Production process of cold head series molten steel in a steel making plant
Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd
Email: info@cxrefractories.com
Website:http://www.cxrefractories.com

Brief introduction of induction furnace lining material

 Refractories used in intermediate frequency furnaces are mostly dry, such as dry ramming materials, also called knotting materials. According to their chemical properties, refractory materials include neutral, alkaline and acidic materials. Induction furnaces, etc., select suitable refractory materials according to the characteristics of the furnace and the environment.

For the lining of the intermediate frequency furnace for melting cast iron, generally cheaper quartz sand is used as the knotting material. When the smelting temperature is high and the smelting conditions are relatively harsh, the service life of the quartz sand knotting material will be greatly reduced, which cannot meet the user's requirements. At this time, it is necessary to use dry knotting materials such as magnesia, magnesia aluminum, magnesia chromium, etc. (that is, the alkaline lining material that everyone often calls).

What are the common molding methods for refractory materials:

There are many molding methods for refractory materials. Common molding methods include extrusion molding, vibration molding, extrusion molding, ramming molding, isostatic pressing molding, melting casting molding, grouting molding, etc. The choice of forming method is mainly based on the nature of the mud, the shape, size and other process requirements of the embryo body. Except for the fact that most refractory materials are formed by press forming and vibration forming is used to form large shaped blanks. Extrusion molding is generally used For the forming of tubular blanks, grouting is generally used for forming hollow thin-walled blanks. Isostatic pressing is currently mainly used in the production of high-performance refractories.

Of course, the choice of molding method is also restricted by the equipment conditions of the production plant, so some products can't use the molding method. In this case, the company should choose other more suitable molding methods on the premise of meeting the technical requirements of the product.

Intermediate frequency furnace refractory knot forming method:

1. The sand should be manufactured according to the regular particle size and mixed evenly with additives. If you choose wet knotting, you can add 1% to 2% of the water, mix and put it for 1 to 2 hours before use.

2. Spread asbestos cloth on the inside of the sensor.

3. Knotted at the bottom of the furnace. After adding the sand material in batches, repeat the tamping with a pointed steel drill with a diameter of 12 to 14 mm each time. The furnace bottom knotting and feeding times are 4 to 5 times. The thickness of the furnace bottom is generally knotted to a regular height, and each knotting time is at least 10 minutes.

4. Put in the crucible core, which is the mould that controls the shape and volume of the crucible.

5. Knotted at the furnace mouth.

Article Source:Which refractory materials are used in the intermediate frequency furnace

Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd

Email: info@cxrefractories.com

Website:http://www.cxrefractories.com

Which refractory materials are used in the intermediate frequency furnace?

Refractories used in intermediate frequency furnaces are mostly dry, such as dry ramming materials, also called knotting materials. According to their chemical properties, refractory materials include neutral, alkaline and acidic materials. Induction furnaces, etc., select suitable refractory materials according to the characteristics of the furnace and the environment.　　

For the lining of the intermediate frequency furnace for melting cast iron, generally cheaper quartz sand is used as the knotting material. When the smelting temperature is high and the smelting conditions are relatively harsh, the service life of the quartz sand knotting material will be greatly reduced, which cannot meet the user's requirements. At this time, it is necessary to use dry knotting materials such as magnesia, magnesia aluminum, magnesia chromium, etc. (that is, the alkaline lining material that everyone often calls).

What are the common molding methods for refractory materials:

There are many molding methods for refractory materials. Common molding methods include extrusion molding, vibration molding, extrusion molding, ramming molding, isostatic pressing molding, melting casting molding, grouting molding, etc. The choice of forming method is mainly based on the nature of the mud, the shape, size and other process requirements of the embryo body. Except for the fact that most refractory materials are formed by press forming and vibration forming is used to form large shaped blanks. Extrusion molding is generally used For the forming of tubular blanks, grouting is generally used for forming hollow thin-walled blanks. Isostatic pressing is currently mainly used in the production of high-performance refractories.

Of course, the choice of molding method is also restricted by the equipment conditions of the production plant, so some products can't use the molding method. In this case, the company should choose other more suitable molding methods on the premise of meeting the technical requirements of the product.

Intermediate frequency furnace refractory knot forming method:

1. The sand should be manufactured according to the regular particle size and mixed evenly with additives. If you choose wet knotting, you can add 1% to 2% of the water, mix and put it for 1 to 2 hours before use.

2. Spread asbestos cloth on the inside of the sensor.
3. Knotted at the bottom of the furnace. After adding the sand material in batches, repeat the tamping with a pointed steel drill with a diameter of 12 to 14 mm each time. The furnace bottom knotting and feeding times are 4 to 5 times. The thickness of the furnace bottom is generally knotted to a regular height, and each knotting time is at least 10 minutes.
4. Put in the crucible core, which is the mould that controls the shape and volume of the crucible.
5. Knotted at the furnace mouth.

Article Source:Development of VOD ladle lining refractories

Company name: Henan Xinmi Changxing Refractory Materials Co.,Ltd

Email: info@cxrefractories.com

Website:http://www.cxrefractories.com