Abstract: With taking the technology measures such as increasing Mn content in steel from 1. 55% ~ 1.65% to 1,75% 〜1. 85% , replacing 0. 20% ~0. 25% Ni in steel by 0. 25% 〜0. 35% Cr, adding 0. 01 % ~0. 04% Ti for microalloying, controlling [ N] ≤80 x 10^-6 and [O] ≤15 x 10^-6 by RH vacuum treatment, decreasing casting secondary cooling water rate from 0. 11 L/kg to 0. 08 L/kg and modifying water distribution ratio to increase temperature of bloom at outlet from 620 ~ 680 ℃ to 700 ~ 750 °C , bloom cooling with shielding and bar products slow cooling, the production cost of R3 grade mooring chain steel is reduced, the longitudinal cracks of 350 mm x 470 mm cast bloom are eliminated and the strength and the toughness at -20 ℃ of products all meet the requirement of standard.

摘要： 通过将钢中Mn含量从1.55%～1.65%提高至1.75%～1.85%,用0.25%～0.35%Cr替代0.20%～0.25%Ni,并加入0.01%～0.04%Ti微合金化;RH真空精炼以控制[N]≤80×10^-6、[O]≤15×10^-6;连铸二冷水量由0.11 L/kg降至0.08 L/kg,并改变配水比例,使出坯温度由620～680℃提高至700～750℃,并采用连铸坯罩冷和钢材缓冷等工艺措施,降低了R3级系泊链钢的生产成本,避免了350 mm×470 mm铸坯纵裂的产生,并使钢材的强度和-20℃韧性均满足标准要求。

关键词: R3级海洋系泊链钢, 大方坯连铸, 工艺优化