... 4140, etcStraightening RollDia. 80~Dia. 900mmH13,4140,4340,EN9,EN19,EN24,EN31,51200,etc2 Material:H13,4130,4140,4150,4340,1035 ... ,1045,EN9,EN19,EN24,EN31,51200,SUJ2,100Cr6,K310,34CrNiMo6,36CrNiMo4,42CrMo4,86CrMoV7,Cr ... D or ASTM A388 – FBH max 4mm5 Forging reduction ratio:≥46 Manufacturing process:steel ingot→forging→rough machining→QT→2th rough machining→induction ...