Open die steel forgings / weight of single piece between 50kg and 5t circular ... -5t2,length no more than 5m3,mim dia over 150mmcylinder forging 1,min OD around 150mm2,weight of single piece between ... authentication of "Classification Society". 5,we usualy use material of steel type of 15#,20#,25#,30#.35#,40#,45#,46 ... requirements we can render excellent heat treatment. ring-rolling-heavy-steel-forging