Silicon barium powder

The inoculation of silicon barium powder is also called ladle inoculation (Ladle Inoculation), which is the inoculation treatment performed when the molten iron flows from the melting furnace or holding furnace to the ladle. This treatment method is simple and convenient, and is currently the most widely used process, but it must be used to follow the operating points.

 

Do not add inoculants to the bottom of empty ladles before pouring. In this way, part of the inoculant will be oxidized before it interacts with the molten iron, and the inoculant is easy to wrap into the slag, resulting in a decrease in its utilization. It is best to start the inoculation process after the iron is tapped, since the amount of molten iron in the ladle is about 1/4 of the amount of iron tapped, and the granular inoculant is evenly and dispersedly sprinkled into the liquid flow through the quantitative funnel, and the amount of molten iron in the ladle The treatment ends when it is about 4/5 of the iron output. In this working method, the stirring effect of the liquid flow can be used to make the inoculant completely dissolve in the high-temperature molten iron and improve its utilization rate. The effect of inoculation treatment by wire feeding method is more stable, but it is still relatively small for inoculation when it is used for tapping.

 

The particle size of silicon-barium powder inoculant is slightly different depending on the amount of molten iron to be processed: when the amount of molten iron is less than 500kg, the particle size should be 2-5mm; when the amount of molten iron is 500kg, the particle size of silicon-barium powder should be 0-8mm. The amount added is generally 0.2-0.4% of the amount of molten iron to be treated, which can be adjusted depending on the type of inoculant and the wall thickness of the casting, and determined through experiments. Adding too much is not only useless, but also has some negative effects because it cannot be completely dissolved in the molten iron, such as slag accumulation in the ladle, slag inclusion defects in castings, blockage of the filter in the gating system, and over-inoculation of the molten iron. Casting defects, etc. If the particle size of the inoculant is too large, it will also affect the inoculation effect because it cannot be completely dissolved in the molten iron, and cause casting defects. 75 ferrosilicon is used for inoculation treatment when tapping iron, and the inoculation effect will quickly decline with the passage of time. After 5 to 7 minutes of inoculation, the decline of the effect can be more than 50%. After about 15 minutes, the inoculation effect will be mostly or All gone. In order to ensure the quality of the casting, it is usually poured within 10 minutes after inoculation. It is best to inoculate the silicon barium powder again when the molten iron is poured into the mold from the ladle.