Resistance to abrasive wear requires high hardness of roll surface materials and high alloy content, the hardness required HRC 55;However, the resistance to fatigue failure requires that the surface material has good toughness and can effectively limit the generation of cracks, so as to avoid the crack expansion and networking under the repeated action of high stress.The ZD series welding wire of zhengzhou machinery research institute is used with proper welding technology to make the welding layer have excellent wear resistance and toughness.Welding wire usage and surfacing process are as follows:
(1) the welding roller body in automatic turntable, using ultrasonic flaw detector to ultrasonic flaw detection of roller and roller surface, after confirm qualified, the roll preheat to 150 ℃, with welding.
(2) use ZD1 submerged arc flux cored wire (∅ 4.0) backing welding crack prevention layer.ZD1 welding wire is a special high toughness transition layer material for surfacing roller press. The surfacing metal has excellent crack resistance and impact toughness.It can effectively prevent the welding crack and fatigue crack from extending and developing to the roll body, and effectively protect the roll body from damage.
(3) using ZD2 submerged arc flux cored wire (∅ 4.0) surfacing transition layer.ZD2 welding wire is a kind of transition layer material with high strength for the extrusion roll of the surfacing roller press. The surfacing metal has high compressive strength and good impact toughness.As a transition layer in wear-resistant surfacing series materials, it can effectively provide support for the high hardness wear-resistant layer on the roll surface and resist the extrusion pressure up to 130MPa.
(4) using ZD3 submerged arc flux cored wire (∅ 4.0) welding wear-resisting layer.ZD3 welding wire is a kind of hardfacing material with high hardness and high toughness for roller surface abrasion resistance of roller extruder. Hardfacing metal has high welding hardness and good crack resistance.Because there are a lot of alloying elements in the hardfacing metal, it has excellent comprehensive properties of anti-abrasive wear and anti-extrusion wear.
(5) with ZD310 finally (∅ 1.6) surfacing flux-cored wire wear stripes.ZD310 welding wire is a special material for hardfacing of wear-resistant decorative pattern layer, with excellent anti-stripping and anti-wear properties .