According to 30 t VOD production data with the conditions of beginning [ C

]

0. 50%-0. 60% and [Si

]

0. 12% -0. 20%

beginning liquid temperature 1 640 -1 650 °C

and argon and nitrogen pressure respectively being 0. 8 x 10

6

- 1.0 x 10

6

Pa and 1.5 x 10

6

- 1. 5 x 10

6

Pa

the nitrogen content in stainless steels (0. 04% - 0. 06% N) at VOD beginning

decarburized by oxygen blown and after reduction and degassing by bottom blowing argon process and bottom blowing nitrogen process have been compared. Results show that after VOD bottom blowing argon refining the nitrogen content in Cr13 type and Cr17 type stainless liquid is respectively 260 x 10

-6

and 300 x 10

-6

its nitrogen alloying

effect is obvious

and in normal atmosphere with nitrogen stirring the average increasing rate of nitrogen in Cr13 type and Cr17 type stainless steel liquid

is respectively 40 x 10

-6

/min and 45 x 10

-6

/min

and with increasing liquid temperature the increasing rate of nitrogen in liquid increases

and with decreasing oxygen content in VOD refining stainless steel liquid the nitrogen alloying effect by bottom blowing nitrogen could be increased.