News

Currently, in the medium-frequency industry, medium-frequency melting furnaces are structurally divided into: Steel-shell furnace And aluminum-cased furnaces, generally speaking.

Steel-shell furnace It boasts a long service life (typically over 10 years under normal operating conditions) and excellent stability. This is achieved through the use of a magnetic conductor, which serves two key functions: First, the magnetic conductor is securely fastened to the induction coil using set screws, creating a robust structure that ensures the coil and magnetic conductor remain firmly connected; second, the magnetic conductor forms a magnetic shielding barrier around the coil. Additionally, furnaces equipped with magnetic conductors are 3% to 5% more energy-efficient than those with aluminum casings. The casting process is highly stable and precise, thanks to the hydraulic tilting furnace mechanism, which allows for precise control over the pouring angle and speed. Furthermore, these furnaces offer superior safety performance, featuring both a molten-metal leakage alarm system and a layer of refractory clay. Due to their outstanding characteristics, steel-cased structures are preferred for furnaces with capacities exceeding 2 tons.

Aluminum-shell furnaces are a simple structural design with a typical service life of around 5 to 8 years. They lack magnetic cores, furnace lining ejection mechanisms, and refractory mortar layers, resulting in poor safety performance. These furnaces are generally used for capacities of 2 tons or less. For example, in a 5-ton medium-frequency furnace, when the furnace is fully charged with molten iron, the entire equipment can weigh between 8 and 10 tons. If an aluminum-shell structure is chosen, when the reducer rotates the furnace body to 95 degrees, the entire furnace will tilt forward, posing significant safety risks. Aluminum-shell furnaces are best suited for users who need to switch production quickly over short periods and operate at small tonnages.

Below is a specific comparison. Steel-shell furnace Compared to aluminum-shell furnaces, steel-shell furnaces have five advantages:

1) Durable and robust, with an elegant and sophisticated appearance—especially for large-capacity furnaces. These require a highly rigid structural design; from the perspective of furnace tilting safety, steel-shell furnaces are preferred whenever possible.

2) The magnetic yoke made of silicon steel sheets shields and emits the magnetic flux lines generated by the induction coil, reducing magnetic leakage, improving thermal efficiency, increasing production output, and achieving energy savings of approximately 5% to 8%.

3) The presence of the furnace lid reduces heat loss and also enhances the safety of the equipment.

4) Long service life: Aluminum oxidizes severely at high temperatures, leading to metal fatigue and embrittlement. At casting facilities, it’s common to see aluminum-shell furnaces with shells that have become badly worn after only about a year of use. In contrast, steel-shell furnaces, thanks to their minimal magnetic leakage, have a significantly longer service life than aluminum-shell furnaces.

5) Safety Performance Steel-shell furnace It significantly outperforms aluminum-shell furnaces. In the melting process, aluminum-shell furnaces are prone to deformation and pose safety risks due to high temperatures and heavy pressure. Steel-shell furnaces, on the other hand, use hydraulic tilting mechanisms, making them safe and reliable.