Causes of slagging in ladle slag line

 

Wanhao is a manufacturer who is specialized in designing various kinds of furnace and making refractory products for electric furnace, ladle, tundish, blast furnace, AOD furnace, IF furnace, etc.

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 Al?O? in aluminum killed steel slag is high. 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.

Wanhao is a manufacturer who is specialized in designing various kinds of furnace and making refractory products for electric furnace, ladle, tundish, blast furnace, AOD furnace, IF furnace, etc.

Article Source:Causes of slagging in ladle slag line

More Refractory Products:https://www.wanhaorefractory.com/en/product.html

Website:https://www.wanhaorefractory.com/


 

 

 

评论

发表评论

此博客中的热门博文

Advantages and disadvantages of fire clay brick

图片
According to production process, fire clay brick is divided into machine made brick and handmade brick. According to structures, fire clay brick is divided into solid brick and hollow brick, and hollow brick can be divided into load-bearing brick and nonbearing brick. Fire clay brick is made at different shapes according to different using requirements. Advantages of fire clay brick： 1. Fire clay brick is environmentally friendly and belongs to resource recycling bricks, so we can rest assured use fire clay brick. Fire clay bricks won’t be harmful to our health. 2.Fire clay brick has advantages of fireproof and heat insulation. Used clay brick can be used as concrete so that to save a lot of resources. 3.The price of fire clay brick is not as expensive as that of other fire bricks. Light weight brick is more expensive than fire clay brick. Besides, fire clay brick is very cheap and very durable 4. Fire clay brick has good moisture-proof function, it also has the a...
阅读全文

The application of carburants

图片
Carburants are for casting iron. Carburants are added to steel, iron and carbon by carbon raw materials. High-quality carbon agent is essential for the production of high-quality steel auxiliary additives. At present, the vast majority of carburants are suitable for electric furnace smelting. Electric furnace smelting of the feeding method, the carbon agent should be with the scrap and other materials into the inside together, the addition of small doses can be added to the surface of the molten iron. But to avoid large quantities of molten iron to feed, to prevent excessive oxidation and the effect of carbon is not obvious and the cast carbon content is not enough. The amount of carbon agent added, according to the ratio of other raw materials and carbon content to set. Features 1.Absorption rate of it is up to 90% or more. 2.Improve the graphite form, increase the number of graphite, fine graphite, improve product mechanical properties, improve pro...
阅读全文

Installation of ladle slide gate and nozzle

图片
1.Before installing the upper steel ladle, first check the use of the water block brick. When the pit or crack occurs, use the repair refractory material to repair it, and then proceed to the next step. 2. Take the water pipe test, check the gap between the nozzle brick and the brick and the positioning of the nozzle brick. It is forbidden to manually remove the head of the water inlet and install it. 3. After checking the appropriate, remove the nozzle brick and apply refractory mud evenly on the outer wall of the upper nozzle brick. The thickness of the refractory mud is controlled at about 10mm (according to the actual clearance). When the gap between the nozzle and the brick is large, the asbestos cloth can be used. The head of the nozzle is evenly wound separately. 4. When installing the water inlet, the nozzle brick should be smoothly fed into the brick. During operation, avoid the gap in the lower part of the nozzle brick. 5. The water inlet must be re...
阅读全文