高Cr合金钢穿孔毛管内螺旋产生原因及其改善措施

Causes for Inner Surface Spiral Mark of Hi-Cr Alloy Steel Pierced Shell and Relevant Countermeasures

分析高Cr合金钢穿孔过程出现的毛管内螺旋现象及其产生原因,提出改进措施.分析认为:钼顶头在使用过程中不断磨损及顶头尾部规圆段长度较短,是毛管产生内表面螺旋的主要原因;通过优化穿孔顶头形状,如缩短钼顶头穿孔锥长度、减小顶头穿孔锥角度等,可增加顶头耐磨程度,从而减轻穿孔后毛管内螺旋痕迹,提高穿孔毛管质量和钼顶头使用寿命,提高生产效率.

Analyzed are the defective inner surface spiral mark as developed with the hi-Cr alloy steel pierced shell, and the reasons for such a defect. Accordingly countermeasures are put forward. It is identified via the analysis that the main reasons for occurrence of the said spiral mark is in-process consistent wearing of the Mo plug, and the rather short rounding-sections of the plug end part. In this case the wear-resistance of the plug will be increased by means of optimizing the plug profile, e.g., shortening the length of the piercing taper, and reducing the taper degree itself. As a result, the inner surface spiral mark will be reduced so as to improve the pierced shell quality, and increase the service span of the Mo plug, and in turn have the productivity enhanced.