锅炉管用钢15CrMoG(/%:0.12~0.18C、0.17~0.35Si、0.40~0.70Mn、≤0.015P、≤0.010S、0.80~1.10Cr、0.40~0.55Mo、≤0.08V、≤0.020Alt)要求非金属夹杂物的级别C≤1.0、Ds≤1.0。该钢的生产流程为铁水预处理-120 t LD-LF-RH-280 mm×380 mm连铸坯-轧制Φ100~Φ120 mm圆管坯。通过铁水深脱硫、LD终点控制0.03%~0.09%C、0.004%~0.012%P、0.006%~0.015%S
加铝铁2.5 kg/t的低铝脱氧
使用碱度为3~4的精炼渣
使中间包钢水的P含量为0.005%~0.012%
S含量0.005%~0.008%
Al含量为0.004%~0.008%
圆管坯的各项指标均满足用户协议要求。
Abstract
The rating of inclusions in steel 15CrMoG for boiler tube (/%: 0. 12 〜0. 18C
0. 17 - 0. 35Si
0. 40 〜0. 70Mn
≤0.015P
≤O. 010S
0. 80 〜1. 10Cr
0. 40 〜0. 55M。≤0. 08 V
≤0. 020Alt) is that C series ≤1.0 and Ds series ≤1.0. The production flow sheet of the steel is hot metal pretreatment-120 t LD-LF-RH-280 mm x 380 mm bloom casting-rolling to Φ 100 ~ Φ120 mm round tube blank. With hot metal deepening desulphurization
LD end point controlling 0. 03% - 0. 09% C
0. 004% -0. 012% P
0. 006% -0. 015% S
low aluminium deoxidation with adding 2. 5 kg/t aluminium-iron
and using refining slag with basicity 3 ~4
as a result in liquid steel in tundish the P content is 0. 005% ~ 0. 012%
the S content is 0. 005% 〜0. 008% and the aluminium content is 0. 004% 〜0. 008%
and each index of round tube blank all meets the requirement of user terms of agreement.