A new type casting chromium iron or casting chromium iron tube rectifier roll is used for steel tube straightener, with main element of the direct roll with C: 1.8-2.8%,Si:<=1.0%,Mn:<=1.0%,P:<=0.04%,S:<=0.04%, Cr:12-22%,Ni:0.5-3.0%,Mo:0.8-3.0%,V:0-1.0%,Cu:0-1.0%, the rest with Fe. Rated in weight of the components should be C: 0.7-1.2%,Si:<=1.0%,Mn:<=1.0%,P:<=0.04%,S:<=0.04%; Cr:8.0-12%,Ni:0.5-2.0%,Mo:0.8-3.0%,V:0-1.0%, with the rest being Fe. Due to even inside and outside of the cast iron steel tube roll, it has higher performance in wearing resistance and toughness, with doubled durability. Due to reduced material, it greatly reduces production cost. Its performance surpasses the international level with life span of it over two times of the national made ones.