【作者】 黄建波；

【导师】 杭乃勤；

【作者基本信息】 武汉科技大学 ， 材料加工工程， 2008， 硕士

【摘要】 本论文结合湘潭钢铁公司第二棒材厂的现场生产实际,由于市场需求变化,二棒材厂产品结构也迫切需要转化,要从原来生产中小规格碳钢圆钢转产大规格的低合金钢管坯。这就需要增大坯料尺寸,对二棒厂的Φ800初轧机孔型系统进行开发设计,对初轧机的轧制的规程进行优化,并对精轧机组孔型系统进行优化改进。由于钢种发生变化,通过在THERMECMASTOR-Z热模拟实验机对20CrMnTiH和40CrA钢种进行热模拟实验,并对实验结果进行分析,得出20CrMnTiH和40CrA钢的流动应力模型,利用此模型计算新孔型系统的轧制力能参数,对轧制压力、轧制力矩、电机能力进行校核。基于对以上研究内容,得到了如下的主要研究结论:1.通过采集应力-应变曲线数据进行多元非线性回归得到20CrMnTiH和40CrA钢的流动应力数学模型,该数学模型的结构简单,计算精度也较高,可用于实际生产中。2.开发的两套初轧机孔型系统,能够满足尺寸和钢种的变化,利用上述模型进行轧制压力、轧制力矩、电机载荷校核,旧轧机仍能满足新钢种大坯料的生产。3..对生产大规格产品进行压下规程优化和配辊,合理安排翻钢道次、提高孔型共用性,将初轧机孔型系统由原意大利设计的四套减到两套,节约了成本并提高了轧机作业率。4.对Φ800可逆式初轧机的速度制度进行优化,缩短了轧制节奏时间,能够满足连轧机的速度匹配要求。5.通过轧制实验得出比较合适的宽展系数,优化设计Φ75~Φ90圆钢椭圆成品前孔孔型及Φ140、Φ150圆钢管坯的成品孔型,避免了原系统轧制时的过充满缺陷。更多还原

【Abstract】 This thesis is based on the Xiangtan Iron and Steel Company the Second Bar factory production actuality, Second Bar factory changed production construction for the changed market demand, they should change from small and middle size carbon round steel to large size low-alloyed steel tube stock. As the size of planchet increased, the original pass system does not suit for producing big bar product, so we optimized the pass system ofΦ800 blooming mill, and improve the finished pass system. Because the type of steel changed, we carried out the thermal simulation experiments in the THERMECMASTOR-Z thermal simulation machine with 20CrMnTiH and 40CrA, and analyzed the experiment results, obtained 20CrMnTiH and the 40CrA flow stress models, then used this model to collate the present rolling physical parameters of optimized pass system, then check rolling force, rolling moment and the motor power.Based on situation research,we obtained the following main research conclusions:1. Through the multi-dimensional non-linear return for stress-strain curve data, we obtained the flow stress mathematical models of 20CrMnTiH and 40CrA. These models are of simple structure and high precision in calculation and can be used in practical production.2. The two set of blooming pass system are able to meet the change of size and type of steel. Check rolling force, rolling moment and the motor power with this model, discovered the old rolling mill still could satisfy the new type of steels’production.3. Designed force down rules and match rollers for large size production, arranged pass reasonably, reinforced pass joint use, we reduce the blooming pass system designed by Italy from four sets to two sets, reduced the cost and increased the efficiency of rolling machine.4. Optimized the speed rules for theΦ800 blooming rolling mill, cut down the rolling time, and matched to the continuous rolling speed.5. We carried out the hot continuous rolling experiment to obtain appropriate broadside, then succeeded in designingΦ75~Φ90 round steel ellipse pass before finished pass andΦ140、Φ150 round tube stock finished pass, solve the overfill problem in the old pass system.更多还原