... alloy steel (42GrMo,38GrMoAI), heating treatment and mechanical processing, hardness is HRC55~58.2.Inner structure: single-layer, multi-layer ... temperature difference <= 1°C, heating transform <= 0.02mm, concentric <= 0.005mm.5.Application: plastics, leather, paper, metal, film and so on.6. ... proposal.We can offer the roller which max diameter is 1 metre and max length is 10 metres. At the same time ...