Heating Roller, Shanghai Donghui Roller is the excellent expert all over the world. 1.Materials: 20#, 45#, forge alloy steel (42GrMo,38GrMoAI), heating treatment and mechanical processing, hardness is HRC55~58. 2.Inner structure: single-layer, multi-layer screw, Z and other structure. 3.Processing: Hard Chrome plating (Dupont formula), chrommantel compact, adhesion strong. 4.Precision: temperature difference
