汽车大梁钢板形缺陷产生的原因及对策

CAUSES AND COUNTERMEASURES OF SHAPE DEFECTS OF BEAM STEEL

汽车大梁钢板形问题具有一定的隐蔽性和复杂性,对钢厂生产和用户加工、使用均造成不良影响,制约着产品质量的进一步提升。为改善汽车大梁钢700L板形,分析了薄规格开平浪形和厚规格纵切侧弯的产生机理,结合河钢邯钢生产实践研究了横向冷却均匀性、层冷模式、冷却水比和层冷侧喷对板形的影响,并制定了相应的改善措施。研究表明开平浪形和纵切边部侧弯与带钢残余应力有关。通过采用微中浪轧制,优化层冷模式和冷却水比,投用边部加热器和中间辊道保温罩以及轧后入库缓冷等措施,成品板形明显改善,用户满意度提高。

The shape problem of beam steel has certain concealment and complexity,which causes adverse effects on the production of steel plant and the processing and use of users,and restricts the further improvement of product quality.In order to improve the shape of automobile beam steel 700L,the mechanism of thin gauge open wave shape and thick gauge longitudinal-cut side bend was analyzed.Combined with the production practice of Hansteel,the effects of transverse cooling uniformity,layer cooling mode,cooling water ratio and layer cooling side spray on the shape of automobile beam steel 700L were studied,and the corresponding improvement measures were formulated.The results show that the strip residual stress is related to the wave shape and longitudinal edge bending.By adopting micro-medium wave rolling,optimizing layer cooling mode and cooling water ratio,adopting edge heater and intermediate roller insulation cover,and putting into storage for slow cooling after rolling,the shape of finished product is obviously improved and the customer satisfaction is improved.