RH Furnace

The full name of RH furnace is RH vacuum circulation degassing refining furnace.

RH system equipment is a kind of secondary refining equipment used to produce high quality steel. The whole metallurgical reaction of molten steel is carried out in a vacuum tank with refractory lining. Lower part of the vacuum tank is composed of two impregnating pipes with refractory lining, and upper part is equipped with hot bends. The extracted gas is discharged to outside of the plant from hot bend to vacuum pump system through gas cooler.

Before molten steel treatment, immerse the immersion tube into molten steel to be treated. When vacuum tank is vacuumized, atmospheric pressure on surface of molten steel forces the molten steel to flow from immersion tube into vacuum tank (height of molten steel can be increased by 1.48m when the vacuum tank is about 0.67mbar). There are two impregnating tubes connected with vacuum tank, one is a rising pipe and the other is a descending pipe. Due to rising pipe continuously blowing argon into molten steel, a higher static pressure difference is produced relative to downcomer without argon blowing, so that the molten steel enters from rising pipe and flows to downcomer through lower part of vacuum tank, repeated so. In vacuum state, argon, hydrogen, carbon monoxide and other gases flowing through vacuum channel water are pumped out in process of liquid steel circulation. At the same time, the molten steel entering into vacuum tank also carries out a series of metallurgical reactions, such as carbon oxygen reaction, etc., so that liquid steel can be purified by cyclic degassing refining.

Advantages of RH furnace treated molten steel are obvious: alloy does not react with slag, alloy is directly added into molten steel with high yield; molten steel can be quickly and evenly mixed; alloy composition can be controlled within a narrow range; gas content is low, inclusions are small, and purity of molten steel is high; The top lance can also be used to adjust temperature of chemical heating, so as to provide molten steel with good fluidity, high purity and in line with casting temperature for continuous casting of multiple heats.