According to double film theory the kinetics model of blowing nitrogen alloying in steel liquid during stainless steel refining is established. By using silicon-molybdenum bar furnace the effect of nitrogen blowing time (0~70 min)

nitrogen partial pressure (N

2

：Ar = 2 : 1

1:2 and 1:1) and temperature (1773~1833K) with constant pressure (101kPa)

constant temperature 1833K and constant flow rate 0.3L/min on nitrogen alloying of stainless steel 316L(/%: 0.031C

0.57Si

1.00Mn

0.921P

0.004S

16.13Cr

10.12N

2.12Mo

0.028N) has been studied. Results show that with increasing nitrogen blowing time and nitrogen partial pressure the nitrogen content in steel increases；with increasing nitrogen flow rate the blowing time for nitrogen conten

t in liquid up to saturating value decreases；with decreasing liquid temperature the dissolvability of nitrogen in steel increases

and the suitable temperature of liquid is 1500°C. The 120t VOD commercial pilot production of stainless steel 316L show that by blowing nitrogen alloying during VOD vacuum period with nitrogen flow rate 42x3m

3

/h the nitrogen content in steel may be up to 0.04%.