连续退火冷轧板表面锈点产生的原因及对策

Causes and countermeasures of rust spots on surface of continuous annealing cold rolled sheet

针对广州JFE钢板有限公司连续退火冷轧板在汽车厂落料后发现的锈点问题,通过对锈点发生规律和形貌、成分分析,并结合连退机组、产品库存以及重卷机组的各个重点生产环节的检查,最终发现导致锈点产生的主要原因是连退机组入口段烘干机管道、退火炉终冷段风箱和管道、水冷段出侧烘干机管道生锈严重产生锈粉等异物,以及产出钢卷库存防护不当,异物污染2号重卷机组辊系导致,并通过采取管道除锈、更换不锈钢风箱、加强钢卷库存卫生管理、对2号重卷机组辊系清洁等措施,解决了锈点问题,满足了汽车厂的使用要求。

In view of the rust spots found in the continuous annealed cold rolled sheet of Guangzhou JFE Steel Plate Co.,Ltd.after blanking in the automobile factory,through the analysis of the occurrence field,morphology and composition of the rust spots,combined with the inspection of the continuous annealing line,product inventory and various key links of the rewinding line,it is finally found that the main causes of the rust spots are the dryer pipes at the inlet section of the continuous annealing line.The bellows and pipes in the final cooling section of the annealing furnace and the dryer pipes at the outlet side of the water cooling section were seriously rusted,resulting in rust powder and other foreign matters,as well as improper protection of the output coil inventory,which polluted the roll system of No.2 rewinding line.The problem of rust spots was solved by taking measures such as pipe rust removal,replacing the stainless steel bellows,strengthening the hygienic management of coil place,cleaning the rolls of No.2 rewinding line,etc.It meets the application requirements of automobile factory.