MZ‑91 高纯镁砖 炼钢转炉内衬选型指南｜MZ‑91 High Purity Magnesia Brick Converter Lining Guide

MZ‑91 高纯镁砖 炼钢转炉内衬选型指南｜MZ‑91 High Purity Magnesia Brick Converter Lining Guide

---

中文部分

炼钢转炉内衬选材是耐火材料工程的核心难点之一。高纯镁砖（MZ‑91）因其优异的化学稳定性和机械强度，在炼钢转炉高温高压工况下表现突出。但选型时容易忽略的关键点有：

1. 工厂现场实测数据：某钢厂转炉内衬使用MZ‑91后，炉衬寿命提升至1200次吹钢，但实际应用中仍需注意炉衬温度分布不均导致热应力集中的问题。建议采用双层结构设计，内层高纯镁砖外加镁铝尖晶石砖作为缓冲层，避免热应力集中损坏。
2. 化学侵蚀匹配：转炉钢水中含有高氧化铁（FeO）和硅酸盐，高纯镁砖的MgO纯度≥91%能有效抵抗FeO的侵蚀，但SiO₂含量过高的钢水会加速碳化镁反应，导致炉衬局部碳化。实操建议：在钢水中加入氧化镁粉末预处理，降低SiO₂含量，延长MZ‑91使用寿命。
3. 踩坑经验：某炼钢厂曾因砖坯尺寸不精确导致拼接缝隙过大，导致钢水渗透，加速内衬损坏。实际应用中，建议采用精密切割 胶粘剂的拼接方式，确保接缝密封无死角。
4. 工厂落地实施：MZ‑91在转炉内衬的实际应用需结合炉衬厚度、炉衬角度、吹钢工艺参数进行优化。例如，炉口部位需采用高密度镁砖，而炉底部位可考虑镁铝尖晶石复合砖作为过渡层，提高整体耐久性。

樊亚东观点：高纯镁砖在转炉内衬的选型，不能仅看理论性能，更要看现场工况的实际应力分布和化学侵蚀环境。过于简单的“高纯镁砖=万能解决方案”会导致踩坑。建议在选型前，先通过热模拟试验和现场温度监测，确保设计与实际工况匹配。

---

English Part

MZ‑91 High Purity Magnesia Brick Converter Lining Guide

Selecting lining materials for converter furnaces is a critical challenge in refractory engineering. MZ‑91 high-purity magnesia bricks excel in high-temperature and high-pressure environments due to their superior chemical stability and mechanical strength. However, key overlooked factors in selection include:

1. Field Test Data: A steel plant using MZ‑91 achieved a converter lining lifespan of 1,200 blast cycles, but real-world application still requires attention to temperature distribution unevenness causing thermal stress concentration. Recommendation: Implement a dual-layer design, with high-purity magnesia bricks internally and magnesia-alumina spinel bricks as a stress-absorbing layer to prevent localized damage.
2. Chemical Erosion Matching: Converter molten steel contains high FeO and silica, where MgO purity ≥91% resists FeO erosion. However, excessive SiO₂ in steel accelerates carbonization of magnesia, leading to localized corrosion. Practical solution: Pre-treat steel with magnesia powder to reduce SiO₂ content, extending MZ‑91 lifespan.
3. Common Pitfalls: A steel plant suffered from inaccurate brick dimensions causing excessive joint gaps, allowing molten steel penetration and accelerating lining failure. Real-world fix: Use precision-cut bricks with adhesive bonding to ensure gap-free joints.
4. On-Site Implementation: MZ‑91’s application in converter linings must align with thickness, lining angle, and blast parameters. For example, the tuyere area should use high-density magnesia bricks, while the bottom layer can adopt magnesia-alumina spinel composite bricks for transition, improving durability.

Fan Yadong’s Insight: Selecting MZ‑91 for converter linings isn’t just about theoretical performance—it’s about matching real-world stress distribution and chemical erosion. Over-reliance on “high-purity magnesia = universal solution” often leads to mistakes. Advise conducting thermal simulation tests and field temperature monitoring before finalizing designs.