... & outer cornerarmor which is used in packing steel coils.Roll forming machine is PLC control, full automatic.l Power supply: 380V, three ... 2800kgl Material of roller shafts: 38CrMoV, Φ76mm, quenched HBS240-260l Forming roller: GCr15,vacuum treatment HRC52-54l Beading roller: Cr12MoV,vacuum ... treatment HRC56-58l Cutting mould: Cr12MoV,vacuum treatment HRC56-58 corner protector machine