大截面内纵高筋薄壁方管的辊拔模具磨损研究

Wear of roll-drawing die for large cross-section thin-walled square tube with longitudinal high ribs

基于Archard磨损模型,用Deform有限元对大截面内纵高筋薄壁方管辊拔模具的磨损行为进行仿真模拟,分析和讨论不同参数对辊轮模具的温度分布场、应力分布场及磨损的影响。结果表明:随模具初始温度增加,辊轮模具温度逐渐增加,辊轮承受的法向应力逐渐减小;随辊拔变形速度增加,辊轮模具温度逐渐降低,辊轮承受的法向应力逐渐增加;随辊轮模具与金属坯料间的摩擦因数增加,辊轮模具温度和辊轮承受的法向应力都逐渐增加。此外,辊轮模具的磨损与辊拔系数密切相关,辊拔系数增加,辊轮模具的磨损增加;辊轮对应的内筋变形区的磨损大于管壁变形区域。综上所述,较优成形工艺参数:模具初始温度为200℃,辊拔变形速度为3 mm/s,辊轮模具与金属坯料的摩擦因数大于0.1。在该参数下预计可生产方管产品968000件。

Based on the Archard wear model,the Deform finite element simulation was used to study the wear behavior of the rolldrawing die for the large‐section thin‐walled square tube with inner longitudinal high ribs.The influences of different parameters on the temperature distribution field,stress distribution field and wear value of the roller were analyzed and discussed.The results show that with the increase of the initial temperature of the roller,the temperature of the roller gradually increases,the normal stress of the roller decreases respectively.With the increase of roll‐drawing deformation speed,the temperature of roller decreases gradually,while the normal stress of roller increases gradually.As the friction coefficient between the roller and the blank increases,the roller temperature and the normal stress of the roller gradually increase.In addition,the wear value of the rolleris is closely related to the roll‐drawing coefficient.The wear value of the roller increases with the increase of the rolldrawing coefficient.The wear value of the rib deformation area corresponding to the roller is greater than that of the tube wall deformation area corresponding to the roller.In summary,the optimum forming process parameters are determined as follows:The initial temperature of the mold is 200℃,the roll‐drawing deformation speed is 3 mm/s,and the friction coefficient between the roller and the blank is greater than 0.1.It is expected that 968000 square tube products can be effectively produced under this parameter.