RH vacuum refining furnace circulates several times per minute.

It is related to the pressure difference between the ascending pipe and the descending pipe. The working flow of RH furnace refining is as follows: Before the molten steel is treated, dip the dip tube into the molten steel in the ladle to be treated. When the vacuum tank is evacuated, molten steel is forced to flow into the vacuum tank through the immersion tube due to the atmospheric pressure on its surface. The two dipping pipes are an ascending pipe and a descending pipe respectively. Because argon gas is continuously blown into molten steel through the riser, compared with the downcomer without argon gas blowing, a higher static pressure difference is generated, so that molten steel enters from the riser, passes through the lower part of the vacuum tank, and then flows into the downcomer to run repeatedly. The pumped gas enters the gas cooler from the hot bend to be cooled, and then is discharged to the vacuum pump system outside the plant.