热轧小圆钢耳子缺陷磨修工艺改进与实践

Technical Improvement and Practice in Grinding off Hot Rolled Bar's Rolling Edges

小圆钢表面耳子缺陷有两种解决方法:≥16 mm时,用手提砂轮机磨去耳子;<16 mm时,用砂轮无芯磨床研磨去除耳子。两种方法在实施前必须对待磨修产品进行一次机械矫直,以保证待修品的平直度。该方法产量低,能耗大,且带来一系列问题。经改进,设计了“三步法”工艺即二次矫直加一次磨修工艺。该方法妥善解决了中低碳和低合金结构钢表面耳子缺陷处理时间长、合格率低的生产难题,使清除小圆钢表面耳子缺陷简便快捷,生产效率高、成本低;同时,圆钢的不圆度、平直度明显改观,产品合格率达100%。

There are two ways to remove small round bars＇ rolling edges： a portable grinder for those with a diameter equal to or greater than 16 mm and a centreless grinding machine for those with a diameter smaller than 16 mm. Mechanical straightening must be done with those bars before being grinded in both cases in order to ensure the straightness of bars. However these two processes have a low productivity and a huge energy consumption, bringing about a series of problems. After modification, a new double-straightening-plus-once-grinding process has been created. The new process has shortened the working period on treating rolling edges of structural steels with medeum-low-carbon or low alloys, and improved the yielding rate, making the rolling edge elimination easier and quicker. It not only reduces the production cost but also improves round bars＇ roundness and straightness for a 100% of product yielding rate.