【摘要】 分析预应力钢丝及钢绞线用SWRH77B盘条拉拔断裂原因。针对平齐状、杯锥状、斜茬状和不规则断口形貌及形成原因,提出改进措施:(1)合理配置连铸二冷工艺,正确调整末端电磁搅拌位置,避免中心偏析和缩孔的形成。(2)认真检查钢坯的表面质量,对有缺陷的坯料应进行修磨,较严重的坯料应回炉。(3)勤检查、更换导卫装置和轧槽,合理分配各道次变形量,调节好各机架间张力,保证料型的合理规范,避免划伤、黏钢、折叠、结疤、耳子等缺陷。(4)增大SWRH77B盘条在斯太尔摩线上的冷却速度,保证相变冷却速度在10~15℃/s,避免出现索氏体化率低和先共析渗碳体大量形成的现象。(5)确定拉拔道次、变形量并选用良好的润滑剂。更多还原

【Abstract】 To analyze drawing fracture cause of SWRH77B wire rod for prestressed steel wire and steel strand.Aiming at the profile such as flush type,cone type,inclined stubble,irregular fracture and their forming cause,the improving measures are put forward:(1)to allocate continuous cast secondary cooling rationally and adjusting end electromagnetic stirring position correctly to avoid forming center segregation and shrinkage cavity;(2) to examine billet surface quality seriously,to grind defect ingot and to return furnace for more defect ingot;(3) to examine and replace guide fittings and groove frequently,to distribute deformation quantity of each pass rationally,to adjust tension among every stander well,ensure specification of ingot shape to avoid such defect as scratch,steel adhesion,lap,scab and wulst;(4)to increase the cooling speed of SWRH77B wire rod in Stelmor line,and to assure phase change cooling speed is from 10 to 15 ℃/s to avoid appearing low sorbitizing rate and a lot of proeutectoid ferrite;(5) to determine rational drawing pass and deformation quantity,and choose good lubricant.更多还原