The full name of RH refining is RH vacuum cycle degassing refining method. It was invented by Germans in 1959. RH is the abbreviation of two German manufacturers using RH refining process.The subsequent RH refining furnace also gradually developed.

RH refining, as an important means of off-furnace refining, has been widely used in the smelting industry due to its short processing cycle, large production capacity, good refining effect and simple operation. RH has developed from an initial degassing device to an off-furnace refining device integrating vacuum decarburization, oxygen decarburization, injection desulfurization, temperature compensation, and uniform temperature and composition. In recent years, with the continuous development of smelting technology and the continuous improvement of smelting capacity, its advantages in smelting have become increasingly apparent, and it has become an off-furnace treatment equipment for modern enterprises.

In the 1980s, RH technology made great progress. The development of RH technology at this stage has the following main characteristics:

(1) Optimize process and equipment parameters and increase production capacity;

(2) Develop multi-purpose refining processes and equipment;

(3) Improve process equipment and combine it with the production process;

(4) Have good economic benefits. The RH method can not only shorten the process flow and improve the yield, but also save deoxidizing agents and alloying elements, and greatly shorten the heat treatment time, which has good economic benefits.

The RH process can accurately control and quickly achieve the predetermined metallurgical indicators at a lower temperature loss. By the mid-1990s, the vacuum refining process and supporting processes of RH were relatively complete, with production capacity ranging from tens of tons to 340 tons. The RH refining process should develop in a multifunctional direction, adding a series of functions such as vacuum decarburization, desulfurization, and composition fine-tuning on the basis of the original degassing.

Therefore, RH refining furnaces are also developing along with the development of RH refining method.