Overview of cranes for continuous casting process in steelmaking

As an important part of the steel production process, the continuous casting process plays a vital role. In this complex and delicate production process, the application of cranes is particularly critical. They not only carry the molten steel from the steelmaking furnace to the continuous casting machine, but also responsible for the continuous casting billet handling, stacking and transportation tasks.

The purpose of this paper is to provide a comprehensive overview of the types, uses, characteristics and configuration requirements of cranes used in the continuous casting process of steelmaking. We will explore the applicability of different types of cranes in the continuous casting process, analyze their respective advantages and limitations, and combined with the actual production needs, put forward reasonable selection recommendations. At the same time, we will also start from the perspective of crane design, to explore its structural characteristics, performance parameters and safety performance requirements, in order to provide reference for the design of cranes.

Through the elaboration of this paper, we expect to be able to help steel enterprises to better understand and grasp the application of cranes in the continuous casting process, to enhance production efficiency, production safety to provide strong support.

Electromagnetic lifting steel plate

Steelmaking continuous casting process overview

Steelmaking continuous casting process is a complex and delicate process, mainly including iron smelting, steel refining and slab continuous casting three major stages, each stage has its own unique process and technical requirements.

Iron smelting stage:

In this stage, the raw materials (molten iron, scrap steel) are first transported to the charging span through the molten iron tanker. The molten iron tanker is a specialized equipment for transporting molten iron, which ensures the safe and efficient transportation of molten iron. The molten iron needs to be pre-treated before entering the converter to remove impurities and harmful elements from it and improve the quality of the molten iron. Subsequently, the casting crane blends the pretreated molten iron into the converter, while the charging crane of the charging span pours the scrap into the converter. The converter is the main equipment for smelting molten iron. Through oxygen blowing, charging and other operations, molten iron and scrap are smelted into molten steel.

Steel refining stage:

The smelted steel needs to be poured into the steel tank and then go through the extra-furnace refining. Extra-furnace refining is the key link to further improve the quality of molten steel. By adding refining agent, blowing argon and other operations, it removes gases, inclusions and other harmful components from molten steel, and improves the purity and performance of molten steel. The refined steel is transported to the ladle rotary table by the casting crane across the steel receiving span. The ladle rotary table is an important equipment connecting smelting and continuous casting, which can smoothly pour the steel from the steel tank into the intermediate tank, providing a stable supply of steel for the subsequent continuous casting process.

Slab continuous casting stage:

The ladle rotary table puts the steel flow from the molten steel tank into the intermediate tank. The intermediate tank is an important link in the continuous casting process, it can play the role of buffer, distribution and purification of steel, to ensure that the steel in the continuous casting process evenly and steadily into the continuous casting machine. Continuous casting machine is the core equipment of continuous casting process, through a series of complex process operations, the steel cast into a certain shape and size of the billet. The cast billet is cut on the billet roller conveyor to form a sized billet. The cut billets are transported to the billet span for storage by slab clamp cranes (or electromagnetic hanging beams, material rake cranes). The casting span is the area for storing and transferring the casting billets, which ensures the safe, orderly storage and timely transfer of the casting billets.

The entire steelmaking continuous casting process requires a high level of technical skill and fine operational control to ensure the quality of the molten steel and the stability of the continuous casting process.

Steel continuous casting process in the configuration and use of cranes

In the steel continuous casting process, in order to meet the different process requirements at various stages, the configuration of a variety of types of cranes, each crane plays an indispensable role. The following is a detailed description of the specific configuration and use:

Slag cross shop:

Slag Tank Bridge Crane: This is a crane specialized in lifting and transporting tipping slag tanks. Its strong lifting capacity and stable operation performance ensure the smooth tipping and transfer of slag tanks, thus effectively improving the efficiency of slag processing.
Electromagnetic bridge crane: This crane is mainly used for lifting and transporting slag, and through electromagnetic adsorption technology, it realizes accurate gripping and carrying of slag, which reduces manual operation and improves work efficiency.
Maintenance hoist crane: this crane is mainly used for the daily maintenance and overhaul of various cranes in the slag span, and its flexibility and portability make the maintenance work more efficient and convenient.

Charging span:

Electromagnetic bridge crane: Here, the electromagnetic bridge crane is mainly used for lifting and transporting scrap into the scrap chute, as well as carrying out other sporadic lifting work on the ground. Its powerful lifting capacity and precise control technology ensure stable lifting and efficient utilization of scrap.
Charging Crane: This crane is specially used for lifting the scrap chute and pouring the scrap into the converter. Its unique lifting method and efficient operation capability provide a stable supply of raw materials for the steelmaking process.
Casting Crane: Casting Crane is another important equipment in the charging span, mainly used for lifting iron and blending iron into the converter. Its powerful lifting capacity and stable operation performance ensure the safe lifting and efficient utilization of molten iron.
Maintenance hoist crane: Similarly, the charging span is also equipped with maintenance hoist cranes, which are used for routine maintenance and overhaul of various cranes to ensure the normal operation of the equipment.

Charging Crane

Other spans:

Refining span, steel receiving span, pouring span, cutting span, spraying span, billeting span: the cranes configured in these areas are mainly used for steel lifting, billet cutting and transportation. Among them, the crane in the refining span is mainly used for the refining process of steel to ensure the quality of steel; the crane in the steel receiving span is responsible for lifting and transporting the refined steel to the pouring span; the crane in the pouring span is used to pour the steel into the molds to form billets; the crane in the cutting span is responsible for cutting the billets into the required lengths; the crane in the printing span is used for printing the billets for marking; and the crane in the billet output span is The cutting span crane is responsible for cutting the billet to the required length; the printing span crane is used to print the billet for marking; and the billet discharge span crane is responsible for transporting the cut and printed billet to the designated location. The configuration and use of these cranes ensures the smooth running and efficient output of the continuous casting process.

Crane characteristics and design requirements

The application of speed control system in the continuous casting process of steelmaking:

The cranes in the continuous casting process of steelmaking generally adopt the speed regulation system, and the introduction of this technology can greatly improve the operating performance of the crane. The speed control system makes the crane starting and braking impact is reduced, the operation is more stable, so as to ensure the safety and efficiency of the production process.
Frequency conversion speed control system compared with the voltage regulator system, has a more excellent performance. It can realize energy saving and consumption reduction through energy feedback technology, which saves a lot of energy consumption cost for enterprises. However, in the case of a larger motor power, the price advantage of the voltage regulator speed control system is more obvious, so it needs to be selected according to the specific circumstances in the actual application.

The structural form of the crane:

In order to meet the different lifting needs in the continuous casting process of steelmaking, the crane mostly adopts the bridge crane structure. This structure includes single girder and double girder form, as well as single trolley and double trolley type. Each structural form has its own unique advantages and scope of application, and can flexibly cope with a variety of complex lifting scenarios.

The choice of spreader:

In the continuous casting process of steelmaking, there are many types of objects to be lifted, so the choice of crane spreader is also crucial. According to the different objects to be lifted, the crane needs to be equipped with different spreaders, such as gantry hooks, electromagnets and so on. The selection of these spreaders needs to fully consider the weight, shape, material and other factors of the lifting object to ensure the safety and efficiency of the lifting process.

Crane design requirements:

The design of the crane needs to fully consider the impact of off-center loading to ensure that it can remain stable when lifting heavy objects such as scrap steel troughs. At the same time, the lifting of scrap steel troughs also needs to meet certain alignment and synchronization requirements of the main and auxiliary hooks to ensure the accuracy and safety of the lifting process. In addition, the cranes used in the steelmaking continuous casting process also need to have high strength, high reliability and good high temperature resistance to adapt to high temperature and harsh working environments. These design requirements are all to ensure that the crane can perform at its best in the steelmaking continuous casting process and create greater value for the company.

Conclusion

In the continuous casting process of steelmaking, the configuration and selection of cranes are crucial to the smooth running of the production process. Different types of cranes play their respective roles in the continuous casting process of steelmaking, ensuring the continuity and efficiency of production. The design of cranes needs to be carried out according to the specific process requirements and working environment to meet the needs of production, while focusing on energy saving and environmental protection and safety.

With the continuous progress of technology, the performance and function of cranes will be further improved to provide more powerful support for the development of steelmaking continuous casting process.