Bridle cylinders, 750*6000,Ra0.01,0.001mm for hot fabric,plastic film/sheet/plate,aluminum foil,cigarette paper. ... 20#, 45#, forge alloy steel (42GrMo,38GrMoAI), heating treatment and mechanical processing, hardness is HRC55~58. Advanced heat treatment process of ... accuracy Bridle cylinders . Bridle cylinders 33-2,750*6000mm,for hot fabric,3D pattern,laser engraving,made by Shanghai Donghui Roller