The pilot production flow sheet of the 350 km/h Chinese Standard EMU DZ2 Axle Steel (/% ：0.24 ~ 0.32C

0.20 ~0.40Si

0.60 ~0. 90Mn

0. 90 〜1.20Cr

0. 50 ~ 1.50Ni

0.20 ~ 0. 30Mo

≤ 0. 010P

≤ 0. 010S) 250 mm x 250 mm is 80 t EBT EAF-LF-VD-8.4 t ingot casting-rolling mill practice. With the process measures including electric arc furnace hot charging >80% pre-treating hot metal

EBT electric arc furnace controlling end [P

]

≤ 0. 006% and [C

]

> 0. 10%

10% heel liquid in tapping

refining of with LF high basicity slag( CaO)/( SiO

2

) =9~12 and white slag hour with twenty minute upwards

after VD process feeding 1. 0 kg/t Si-Ca wire and argon shielding

ingot casting

the cleanliness of produced steel DZ2 is [O

]

≤ 10x 10

-6

[ H

]

≤ 1. 0 x 10

-6

P≤ 0.008%

S ≤ 0.005%

and inclusion rating of A

B

C

D and Ds series

<

1.0

the technical indexes of bloom and axle of steel DZ2 all meet TJ/CL520-2016《 Tentative specifications of DZ2 EMU Axle》

bloom and axle is past the step-up judging of the railway head office organizational

and finished 6 X 10

5

km handle examine test.