Comparison between the metallurgical characteristics of 41 ~45 t original circular ladle and new-type ladle has been carried out by using geometric similarity ratio 1：3.4 water model and the optimum location of argon blowing is obtained. Results show that for original ladle the height-diameter ratio is rather large

the mixing time is longer and the process isn't stable ； and for new ladle the height-diameter ratio decreases and the mixing time reduces obviously. While it is found that the blowing effect of single porous brick is better that of double porous bricks at new-type ladle bottom. Production practice indicates that with using new-type ladle the mixing time after adding carbon powder decreases from original 8 ~ 10 min to 4 min

the nozzle auto-open pouring ratio increases from 80% to more than 95%

and the large inclusion occurrence ratio in steel products decreases from original 3% to 1. 5%.