the temperature before beginning the decarburization operation was 1 630 u00b0 to 1 640 u00b0 c the decarburization behavior was controlled to accord with the decarburization coefficient defined by equation 2 where c s is the c before beginning the rh operation c is the c after the blowing of oxidizing gas was terminated in the rh operation k is the decarburization coefficient t nm 3 and q o 2 is the amount of oxygen nm 3 t further the amount of temperature decrease was defined by the following equation 3 where t s was the temperature u00b0 c of the molten steel when the rh operation was started and t was the temperature u00b0 c of the molten steel after the blowing of oxygen was terminated it can be seen from fig7 and 8 that the preferred range of the value u03b1 which satisfied both excellent decarburization rate and excellent resistance to temperature decrease is from about 1 to 4 more specifically if u03b1 exceeds about 4 both the decarburization coefficient and the temperature decrease vary greatly causing the decarburization rate to decrease this is due to the fact that cr is oxidized with the decarburization and that cr oxidation impedes decarburization if in contrast u03b1 is about 1 or less the temperature decrease is resisted due to secondary combustion but decarburization becomes inferior oxygen at the rate of flow of 15 nm 3 min was supplied to 100 tons of sus 304 molten stainless steel which was reduced and tapped by a top blow converter for five minutes after a lapse of four minutes from.