Introduction
In continuous casting, the mold is the most important placed in the entire process. The mold is a closed cavity into which the steel is poured and the product is obtained after solidification. The heat transfer from die to product, the layout of the core pin and the surface of the die are the main factors in determining the quality of the finished product. Generally speaking, the common support structure of car bottom is the bottom plate and five side plates. In conventional casting, this design is widely used and is considered an effective support structure.
However, the support structure of bottom plate and five side plates is not suitable for meeting the special requirements of high efficiency continuous casting of some products.. The difference between continuous casting and conventional casting is the speed of feeding. The feeding speed of high efficiency continuous casting is relatively fast, which is several times that of conventional casting. Therefore, the support structure of bottom plate and five side plates cannot meet the requirements of quick feeding and heat transfer. In order to meet the special requirements of high efficiency continuous casting at the bottom of the crystallizer, a special support structure is needed.
The Oscillating Piston Technique
The Oscillating Piston Technique (OPT) is a special support structure for the purpose of continuously casting high performance products. With OPT, an oscillating piston is installed at the bottom of the mold. The main purpose of the oscillating piston is to fill the gap between the bottom of the mold and the car bottom when the steel solidifies. The gap reduces the pressure of the cast steel, which helps accelerate the cooling rate and improve the fluidity of the steel. Therefore, this support structure can support the high efficiency continuous casting at the bottom of the crystallizer more effectively
In addition, the oscillating piston which is the support structure has several advantages. Firstly, the oscillating piston can provide additional cooling capacity so as to maintain the shape of the product when the steel is quickly cooling. Secondly, the oscillating piston can also improve the surface quality of the product greatly. Lastly, the oscillating piston technique is highly automated, therefore operators can remain safe by controlling the process with few intervention.
The Core Pin
The core pin, also known as center pin, is an important part of the Carbottom structure. The correct arrangement of core pin, is an important factor affecting the performance and quality of the product.
The core pin, which is the core part of the Carbottom structure, is usually made by cast iron, which is easy to process. Generally, the core pin is required to be perpendicular to the surface of the car bottom and must have even spacing. The spacing is usually 3-5 mm between the outside of the core pin and the inside of the car bottom.
The main function of core pin is to support the car bottom and ensure that the car bottom casting is in the correct shape. Besides, the core pin also helps to ensure the even cooling of the cast steel since it helps to reduce the heat transfer to the adjacent area. Moreover, the core pin is also important in determining the surface finish of the car bottom. By adjusting the position of the core pin, the operators can adjust the shape of outgassing and the micro structure of surface.
Conclusion
In conclusion, in order to meet the special requirements of high efficiency continuous casting of some products, a special support structure is needed. The Oscillating Piston Technique (OPT) is one effective support structure for this purpose. The added cooling capacity and improved surface quality of the product makes OPT an attractive solution. The core pin is an important part of the Carbottom support structure and its correct arrangement is crucial for product performance and quality. This points out how important it is to use an efficient and practical support structure such as OPT to support the bottom of the crystallizer during high efficiency continuous casting.
