... structure is welded with 16 channel steel, firm and durable3. The upper steel plate will be welded after ... . One pair.Corrugating roller raw materials: 48CrMo alloy steel, made in Shanghai.Flute: A, C, B ... roller: Ø328MM one pcs, made in special hard steel, surface do grinding and chromed.Gluing roller: Ø250MM ... drive, gear is made from high quality alloy steel and the dip oil type, low noise, ...