Decarburization vacuum heat treatment

Vacuum furnace deep decarburization process basically is decided according to the processing of oxygen, the concentration of the surplus in molten steel is still very high, even more than three hundred, and then this case should increase the air flow, the flow of the whole flow ascension in 150 cubic meters per hour, and open the booster pump, the whole vacuum to around 1 milli mpa, guarantee the circulation of misery time nine minutes, then, can effectively reduce them to about 15 mm in mpa, just water surplus oxygen content is low, can also be combined with a carbon content and oxygen content to choose.
With the reduction of carbon content in the steel water, the decarbonization rate becomes slow, the carbon diffusion becomes the restrictive link, and other measures must be taken to continue to decarbonize. At this point, the oxygen content determined by the light treatment is determined.

First, when the surplus of the oxygen content in molten steel is still high (greater than 300 PPM), to increase gas flow ascension to 150 nm3 / h, and open the E3, E2, E1 booster pump, vacuum to around 1 mbar, ensure that the cycle of 9 minutes decarbonization time, carbon can be to around 15 PPM.
Second, if the surplus oxygen in molten steel is low, can be combined for the first time, carbon content and oxygen content, according to the empirical formula about 150 parts per million 100 PPM of carbon oxygen, oxygen plus surplus 200 PPM, calculate the also need to increase the oxygen content. In the end, the T-COB oxygen gun was used to decarbonize the oxygen. The production practice shows that in the gun position of 4220mm, oxygen pressure is 14 to 16 bar, and oxygen flow is 1800 Nm3/ h, which can increase the oxygen in the steel water by 550ppm when blowing 100Nm3 of oxygen. You can calculate the volume of oxygen blowing.